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1 | #include <windows.h> |
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2 | #include <stdio.h> |
3 | #include <stdlib.h> |
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4 | #include <stdarg.h> |
5 | #include <assert.h> |
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6 | |
7 | #include "putty.h" |
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8 | #include "tree234.h" |
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9 | #include "ssh.h" |
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10 | |
11 | #ifndef FALSE |
12 | #define FALSE 0 |
13 | #endif |
14 | #ifndef TRUE |
15 | #define TRUE 1 |
16 | #endif |
17 | |
765c4200 |
18 | /* uncomment this for packet level debugging */ |
19 | /* #define DUMP_PACKETS */ |
20 | |
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21 | #define logevent(s) { logevent(s); \ |
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22 | if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) \ |
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23 | { fprintf(stderr, "%s\n", s); fflush(stderr); } } |
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24 | |
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25 | #define bombout(msg) ( ssh_state = SSH_STATE_CLOSED, \ |
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26 | (s ? sk_close(s), s = NULL : 0), \ |
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27 | connection_fatal msg ) |
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28 | |
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29 | #define SSH1_MSG_DISCONNECT 1 /* 0x1 */ |
30 | #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */ |
31 | #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */ |
32 | #define SSH1_CMSG_USER 4 /* 0x4 */ |
33 | #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */ |
34 | #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */ |
35 | #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */ |
36 | #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */ |
37 | #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */ |
38 | #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */ |
39 | #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */ |
40 | #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */ |
41 | #define SSH1_SMSG_SUCCESS 14 /* 0xe */ |
42 | #define SSH1_SMSG_FAILURE 15 /* 0xf */ |
43 | #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */ |
44 | #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */ |
45 | #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */ |
46 | #define SSH1_CMSG_EOF 19 /* 0x13 */ |
47 | #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */ |
48 | #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */ |
49 | #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */ |
50 | #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */ |
51 | #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */ |
52 | #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */ |
53 | #define SSH1_SMSG_X11_OPEN 27 /* 0x1b */ |
54 | #define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */ |
55 | #define SSH1_MSG_PORT_OPEN 29 /* 0x1d */ |
56 | #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */ |
57 | #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */ |
58 | #define SSH1_MSG_IGNORE 32 /* 0x20 */ |
59 | #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */ |
60 | #define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */ |
61 | #define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */ |
62 | #define SSH1_MSG_DEBUG 36 /* 0x24 */ |
63 | #define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */ |
64 | #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */ |
65 | #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */ |
66 | #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */ |
67 | #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */ |
68 | #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */ |
69 | #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */ |
70 | |
71 | #define SSH1_AUTH_TIS 5 /* 0x5 */ |
72 | #define SSH1_AUTH_CCARD 16 /* 0x10 */ |
73 | |
74 | #define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */ |
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75 | /* Mask for protoflags we will echo back to server if seen */ |
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76 | #define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */ |
77 | |
78 | #define SSH2_MSG_DISCONNECT 1 /* 0x1 */ |
79 | #define SSH2_MSG_IGNORE 2 /* 0x2 */ |
80 | #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */ |
81 | #define SSH2_MSG_DEBUG 4 /* 0x4 */ |
82 | #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */ |
83 | #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */ |
84 | #define SSH2_MSG_KEXINIT 20 /* 0x14 */ |
85 | #define SSH2_MSG_NEWKEYS 21 /* 0x15 */ |
86 | #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */ |
87 | #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */ |
88 | #define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */ |
89 | #define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */ |
90 | #define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */ |
91 | #define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */ |
92 | #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */ |
93 | #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */ |
94 | #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */ |
95 | #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */ |
96 | #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */ |
97 | #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */ |
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98 | #define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */ |
99 | #define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */ |
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100 | #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */ |
101 | #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */ |
102 | #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */ |
103 | #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */ |
104 | #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */ |
105 | #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */ |
106 | #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */ |
107 | #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */ |
108 | #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */ |
109 | #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */ |
110 | #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */ |
111 | #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */ |
112 | #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */ |
113 | #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */ |
114 | |
115 | #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */ |
116 | #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */ |
117 | #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */ |
118 | #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */ |
119 | #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */ |
120 | #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */ |
121 | #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */ |
122 | #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */ |
123 | #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */ |
124 | #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */ |
125 | #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */ |
126 | #define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */ |
127 | #define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */ |
128 | #define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */ |
129 | #define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */ |
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130 | |
131 | static const char *const ssh2_disconnect_reasons[] = { |
132 | NULL, |
133 | "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT", |
134 | "SSH_DISCONNECT_PROTOCOL_ERROR", |
135 | "SSH_DISCONNECT_KEY_EXCHANGE_FAILED", |
136 | "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED", |
137 | "SSH_DISCONNECT_MAC_ERROR", |
138 | "SSH_DISCONNECT_COMPRESSION_ERROR", |
139 | "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE", |
140 | "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED", |
141 | "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE", |
142 | "SSH_DISCONNECT_CONNECTION_LOST", |
143 | "SSH_DISCONNECT_BY_APPLICATION", |
144 | "SSH_DISCONNECT_TOO_MANY_CONNECTIONS", |
145 | "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER", |
146 | "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE", |
147 | "SSH_DISCONNECT_ILLEGAL_USER_NAME", |
148 | }; |
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149 | |
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150 | #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */ |
151 | #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */ |
152 | #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */ |
153 | #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */ |
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154 | |
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155 | #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */ |
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156 | |
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157 | /* |
158 | * Various remote-bug flags. |
159 | */ |
160 | #define BUG_CHOKES_ON_SSH1_IGNORE 1 |
161 | #define BUG_SSH2_HMAC 2 |
162 | |
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163 | #define GET_32BIT(cp) \ |
164 | (((unsigned long)(unsigned char)(cp)[0] << 24) | \ |
165 | ((unsigned long)(unsigned char)(cp)[1] << 16) | \ |
166 | ((unsigned long)(unsigned char)(cp)[2] << 8) | \ |
167 | ((unsigned long)(unsigned char)(cp)[3])) |
168 | |
169 | #define PUT_32BIT(cp, value) { \ |
170 | (cp)[0] = (unsigned char)((value) >> 24); \ |
171 | (cp)[1] = (unsigned char)((value) >> 16); \ |
172 | (cp)[2] = (unsigned char)((value) >> 8); \ |
173 | (cp)[3] = (unsigned char)(value); } |
174 | |
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175 | enum { PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM }; |
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176 | |
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177 | /* Coroutine mechanics for the sillier bits of the code */ |
178 | #define crBegin1 static int crLine = 0; |
179 | #define crBegin2 switch(crLine) { case 0:; |
180 | #define crBegin crBegin1; crBegin2; |
181 | #define crFinish(z) } crLine = 0; return (z) |
182 | #define crFinishV } crLine = 0; return |
183 | #define crReturn(z) \ |
184 | do {\ |
185 | crLine=__LINE__; return (z); case __LINE__:;\ |
186 | } while (0) |
187 | #define crReturnV \ |
188 | do {\ |
189 | crLine=__LINE__; return; case __LINE__:;\ |
190 | } while (0) |
191 | #define crStop(z) do{ crLine = 0; return (z); }while(0) |
192 | #define crStopV do{ crLine = 0; return; }while(0) |
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193 | #define crWaitUntil(c) do { crReturn(0); } while (!(c)) |
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194 | #define crWaitUntilV(c) do { crReturnV; } while (!(c)) |
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195 | |
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196 | extern char *x11_init(Socket *, char *, void *); |
197 | extern void x11_close(Socket); |
198 | extern void x11_send(Socket, char *, int); |
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199 | extern void x11_invent_auth(char *, int, char *, int); |
200 | |
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201 | extern char *pfd_newconnect(Socket * s, char *hostname, int port, void *c); |
202 | extern char *pfd_addforward(char *desthost, int destport, int port); |
203 | extern void pfd_close(Socket s); |
204 | extern void pfd_send(Socket s, char *data, int len); |
205 | extern void pfd_confirm(Socket s); |
206 | |
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207 | /* |
208 | * Ciphers for SSH2. We miss out single-DES because it isn't |
209 | * supported; also 3DES and Blowfish are both done differently from |
210 | * SSH1. (3DES uses outer chaining; Blowfish has the opposite |
211 | * endianness and different-sized keys.) |
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212 | */ |
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213 | const static struct ssh2_ciphers *ciphers[] = { |
214 | &ssh2_aes, |
215 | &ssh2_blowfish, |
216 | &ssh2_3des, |
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217 | }; |
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218 | |
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219 | const static struct ssh_kex *kex_algs[] = { |
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220 | &ssh_diffiehellman_gex, |
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221 | &ssh_diffiehellman |
222 | }; |
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223 | |
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224 | const static struct ssh_signkey *hostkey_algs[] = { &ssh_rsa, &ssh_dss }; |
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225 | |
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226 | static void nullmac_key(unsigned char *key) |
227 | { |
228 | } |
229 | static void nullmac_generate(unsigned char *blk, int len, |
230 | unsigned long seq) |
231 | { |
232 | } |
233 | static int nullmac_verify(unsigned char *blk, int len, unsigned long seq) |
234 | { |
235 | return 1; |
236 | } |
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237 | const static struct ssh_mac ssh_mac_none = { |
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238 | nullmac_key, nullmac_key, nullmac_generate, nullmac_verify, "none", 0 |
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239 | }; |
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240 | const static struct ssh_mac *macs[] = { |
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241 | &ssh_sha1, &ssh_md5, &ssh_mac_none |
242 | }; |
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243 | const static struct ssh_mac *buggymacs[] = { |
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244 | &ssh_sha1_buggy, &ssh_md5, &ssh_mac_none |
245 | }; |
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246 | |
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247 | static void ssh_comp_none_init(void) |
248 | { |
249 | } |
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250 | static int ssh_comp_none_block(unsigned char *block, int len, |
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251 | unsigned char **outblock, int *outlen) |
252 | { |
253 | return 0; |
254 | } |
255 | static int ssh_comp_none_disable(void) |
256 | { |
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257 | return 0; |
258 | } |
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259 | const static struct ssh_compress ssh_comp_none = { |
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260 | "none", |
261 | ssh_comp_none_init, ssh_comp_none_block, |
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262 | ssh_comp_none_init, ssh_comp_none_block, |
263 | ssh_comp_none_disable |
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264 | }; |
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265 | extern const struct ssh_compress ssh_zlib; |
266 | const static struct ssh_compress *compressions[] = { |
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267 | &ssh_zlib, &ssh_comp_none |
268 | }; |
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269 | |
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270 | enum { /* channel types */ |
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271 | CHAN_MAINSESSION, |
272 | CHAN_X11, |
273 | CHAN_AGENT, |
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274 | CHAN_SOCKDATA, |
275 | CHAN_SOCKDATA_DORMANT /* one the remote hasn't confirmed */ |
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276 | }; |
277 | |
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278 | /* |
279 | * 2-3-4 tree storing channels. |
280 | */ |
281 | struct ssh_channel { |
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282 | unsigned remoteid, localid; |
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283 | int type; |
284 | int closes; |
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285 | struct ssh2_data_channel { |
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286 | unsigned char *outbuffer; |
287 | unsigned outbuflen, outbufsize; |
288 | unsigned remwindow, remmaxpkt; |
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289 | } v2; |
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290 | union { |
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291 | struct ssh_agent_channel { |
292 | unsigned char *message; |
293 | unsigned char msglen[4]; |
294 | int lensofar, totallen; |
295 | } a; |
296 | struct ssh_x11_channel { |
297 | Socket s; |
298 | } x11; |
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299 | struct ssh_pfd_channel { |
300 | Socket s; |
301 | } pfd; |
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302 | } u; |
303 | }; |
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304 | |
d74d141c |
305 | /* |
bc240b21 |
306 | * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH |
307 | * 2 use this structure in different ways, reflecting SSH 2's |
308 | * altogether saner approach to port forwarding. |
309 | * |
310 | * In SSH 1, you arrange a remote forwarding by sending the server |
311 | * the remote port number, and the local destination host:port. |
312 | * When a connection comes in, the server sends you back that |
313 | * host:port pair, and you connect to it. This is a ready-made |
314 | * security hole if you're not on the ball: a malicious server |
315 | * could send you back _any_ host:port pair, so if you trustingly |
316 | * connect to the address it gives you then you've just opened the |
317 | * entire inside of your corporate network just by connecting |
318 | * through it to a dodgy SSH server. Hence, we must store a list of |
319 | * host:port pairs we _are_ trying to forward to, and reject a |
320 | * connection request from the server if it's not in the list. |
321 | * |
322 | * In SSH 2, each side of the connection minds its own business and |
323 | * doesn't send unnecessary information to the other. You arrange a |
324 | * remote forwarding by sending the server just the remote port |
325 | * number. When a connection comes in, the server tells you which |
326 | * of its ports was connected to; and _you_ have to remember what |
327 | * local host:port pair went with that port number. |
328 | * |
329 | * Hence: in SSH 1 this structure stores host:port pairs we intend |
330 | * to allow connections to, and is indexed by those host:port |
331 | * pairs. In SSH 2 it stores a mapping from source port to |
332 | * destination host:port pair, and is indexed by source port. |
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333 | */ |
334 | struct ssh_rportfwd { |
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335 | unsigned sport, dport; |
336 | char dhost[256]; |
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337 | }; |
338 | |
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339 | struct Packet { |
340 | long length; |
341 | int type; |
342 | unsigned char *data; |
343 | unsigned char *body; |
344 | long savedpos; |
345 | long maxlen; |
346 | }; |
347 | |
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348 | static SHA_State exhash, exhashbase; |
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349 | |
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350 | static Socket s = NULL; |
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351 | |
352 | static unsigned char session_key[32]; |
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353 | static int ssh1_compressing; |
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354 | static int ssh1_remote_protoflags; |
355 | static int ssh1_local_protoflags; |
db7d555c |
356 | static int ssh_agentfwd_enabled; |
9c964e85 |
357 | static int ssh_X11_fwd_enabled; |
7d503c31 |
358 | static int ssh_remote_bugs; |
57476f6b |
359 | static const struct ssh_cipher *cipher = NULL; |
0a3f1d48 |
360 | static const struct ssh2_cipher *cscipher = NULL; |
361 | static const struct ssh2_cipher *sccipher = NULL; |
57476f6b |
362 | static const struct ssh_mac *csmac = NULL; |
363 | static const struct ssh_mac *scmac = NULL; |
364 | static const struct ssh_compress *cscomp = NULL; |
365 | static const struct ssh_compress *sccomp = NULL; |
366 | static const struct ssh_kex *kex = NULL; |
e055a386 |
367 | static const struct ssh_signkey *hostkey = NULL; |
65a22376 |
368 | static unsigned char ssh2_session_id[20]; |
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369 | int (*ssh_get_line) (const char *prompt, char *str, int maxlen, |
370 | int is_pw) = NULL; |
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371 | |
372 | static char *savedhost; |
373 | static int savedport; |
374 | static int ssh_send_ok; |
0965bee0 |
375 | static int ssh_echoing, ssh_editing; |
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376 | |
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377 | static tree234 *ssh_channels; /* indexed by local id */ |
57476f6b |
378 | static struct ssh_channel *mainchan; /* primary session channel */ |
379 | |
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380 | static tree234 *ssh_rportfwds; |
381 | |
57476f6b |
382 | static enum { |
3687d221 |
383 | SSH_STATE_PREPACKET, |
57476f6b |
384 | SSH_STATE_BEFORE_SIZE, |
385 | SSH_STATE_INTERMED, |
386 | SSH_STATE_SESSION, |
387 | SSH_STATE_CLOSED |
3687d221 |
388 | } ssh_state = SSH_STATE_PREPACKET; |
57476f6b |
389 | |
3687d221 |
390 | static int size_needed = FALSE, eof_needed = FALSE; |
57476f6b |
391 | |
392 | static struct Packet pktin = { 0, 0, NULL, NULL, 0 }; |
393 | static struct Packet pktout = { 0, 0, NULL, NULL, 0 }; |
b185170a |
394 | static unsigned char *deferred_send_data = NULL; |
395 | static int deferred_len = 0, deferred_size = 0; |
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396 | |
397 | static int ssh_version; |
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398 | static void (*ssh_protocol) (unsigned char *in, int inlen, int ispkt); |
57476f6b |
399 | static void ssh1_protocol(unsigned char *in, int inlen, int ispkt); |
400 | static void ssh2_protocol(unsigned char *in, int inlen, int ispkt); |
401 | static void ssh_size(void); |
32874aea |
402 | static void ssh_special(Telnet_Special); |
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403 | static void ssh2_try_send(struct ssh_channel *c); |
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404 | static void ssh2_add_channel_data(struct ssh_channel *c, char *buf, |
405 | int len); |
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406 | |
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407 | static int (*s_rdpkt) (unsigned char **data, int *datalen); |
57476f6b |
408 | |
409 | static struct rdpkt1_state_tag { |
410 | long len, pad, biglen, to_read; |
411 | unsigned long realcrc, gotcrc; |
412 | unsigned char *p; |
413 | int i; |
414 | int chunk; |
415 | } rdpkt1_state; |
416 | |
960e736a |
417 | static struct rdpkt2_state_tag { |
418 | long len, pad, payload, packetlen, maclen; |
419 | int i; |
420 | int cipherblk; |
421 | unsigned long incoming_sequence; |
422 | } rdpkt2_state; |
423 | |
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424 | static int ssh_channelcmp(void *av, void *bv) |
425 | { |
426 | struct ssh_channel *a = (struct ssh_channel *) av; |
427 | struct ssh_channel *b = (struct ssh_channel *) bv; |
428 | if (a->localid < b->localid) |
429 | return -1; |
430 | if (a->localid > b->localid) |
431 | return +1; |
dacbd0e8 |
432 | return 0; |
433 | } |
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434 | static int ssh_channelfind(void *av, void *bv) |
435 | { |
436 | unsigned *a = (unsigned *) av; |
437 | struct ssh_channel *b = (struct ssh_channel *) bv; |
438 | if (*a < b->localid) |
439 | return -1; |
440 | if (*a > b->localid) |
441 | return +1; |
dacbd0e8 |
442 | return 0; |
443 | } |
444 | |
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445 | static int ssh_rportcmp_ssh1(void *av, void *bv) |
d74d141c |
446 | { |
447 | struct ssh_rportfwd *a = (struct ssh_rportfwd *) av; |
448 | struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv; |
449 | int i; |
bc240b21 |
450 | if ( (i = strcmp(a->dhost, b->dhost)) != 0) |
d74d141c |
451 | return i < 0 ? -1 : +1; |
bc240b21 |
452 | if (a->dport > b->dport) |
453 | return +1; |
454 | if (a->dport < b->dport) |
455 | return -1; |
456 | return 0; |
457 | } |
458 | |
459 | static int ssh_rportcmp_ssh2(void *av, void *bv) |
460 | { |
461 | struct ssh_rportfwd *a = (struct ssh_rportfwd *) av; |
462 | struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv; |
463 | int i; |
464 | if (a->sport > b->sport) |
d74d141c |
465 | return +1; |
bc240b21 |
466 | if (a->sport < b->sport) |
467 | return -1; |
d74d141c |
468 | return 0; |
469 | } |
470 | |
32874aea |
471 | static int alloc_channel_id(void) |
472 | { |
260f3dec |
473 | const unsigned CHANNEL_NUMBER_OFFSET = 256; |
474 | unsigned low, high, mid; |
d2371c81 |
475 | int tsize; |
476 | struct ssh_channel *c; |
477 | |
478 | /* |
479 | * First-fit allocation of channel numbers: always pick the |
480 | * lowest unused one. To do this, binary-search using the |
481 | * counted B-tree to find the largest channel ID which is in a |
482 | * contiguous sequence from the beginning. (Precisely |
483 | * everything in that sequence must have ID equal to its tree |
484 | * index plus CHANNEL_NUMBER_OFFSET.) |
485 | */ |
486 | tsize = count234(ssh_channels); |
487 | |
32874aea |
488 | low = -1; |
489 | high = tsize; |
d2371c81 |
490 | while (high - low > 1) { |
491 | mid = (high + low) / 2; |
492 | c = index234(ssh_channels, mid); |
493 | if (c->localid == mid + CHANNEL_NUMBER_OFFSET) |
494 | low = mid; /* this one is fine */ |
495 | else |
496 | high = mid; /* this one is past it */ |
497 | } |
498 | /* |
499 | * Now low points to either -1, or the tree index of the |
500 | * largest ID in the initial sequence. |
501 | */ |
502 | { |
503 | unsigned i = low + 1 + CHANNEL_NUMBER_OFFSET; |
504 | assert(NULL == find234(ssh_channels, &i, ssh_channelfind)); |
505 | } |
506 | return low + 1 + CHANNEL_NUMBER_OFFSET; |
507 | } |
508 | |
32874aea |
509 | static void c_write(char *buf, int len) |
510 | { |
67779be7 |
511 | if ((flags & FLAG_STDERR)) { |
32874aea |
512 | int i; |
513 | for (i = 0; i < len; i++) |
514 | if (buf[i] != '\r') |
515 | fputc(buf[i], stderr); |
fb09bf1c |
516 | return; |
517 | } |
fe50e814 |
518 | from_backend(1, buf, len); |
3bdaf79d |
519 | } |
520 | |
32874aea |
521 | static void c_write_untrusted(char *buf, int len) |
522 | { |
a209e957 |
523 | int i; |
524 | for (i = 0; i < len; i++) { |
32874aea |
525 | if (buf[i] == '\n') |
526 | c_write("\r\n", 2); |
527 | else if ((buf[i] & 0x60) || (buf[i] == '\r')) |
528 | c_write(buf + i, 1); |
a209e957 |
529 | } |
530 | } |
531 | |
32874aea |
532 | static void c_write_str(char *buf) |
533 | { |
1408a877 |
534 | c_write(buf, strlen(buf)); |
535 | } |
536 | |
fb09bf1c |
537 | /* |
538 | * Collect incoming data in the incoming packet buffer. |
e5574168 |
539 | * Decipher and verify the packet when it is completely read. |
540 | * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets. |
fb09bf1c |
541 | * Update the *data and *datalen variables. |
542 | * Return the additional nr of bytes needed, or 0 when |
543 | * a complete packet is available. |
544 | */ |
e5574168 |
545 | static int ssh1_rdpkt(unsigned char **data, int *datalen) |
fb09bf1c |
546 | { |
57476f6b |
547 | struct rdpkt1_state_tag *st = &rdpkt1_state; |
374330e2 |
548 | |
549 | crBegin; |
374330e2 |
550 | |
32874aea |
551 | next_packet: |
37508af4 |
552 | |
fb09bf1c |
553 | pktin.type = 0; |
554 | pktin.length = 0; |
374330e2 |
555 | |
57476f6b |
556 | for (st->i = st->len = 0; st->i < 4; st->i++) { |
fb09bf1c |
557 | while ((*datalen) == 0) |
32874aea |
558 | crReturn(4 - st->i); |
57476f6b |
559 | st->len = (st->len << 8) + **data; |
fb09bf1c |
560 | (*data)++, (*datalen)--; |
561 | } |
374330e2 |
562 | |
fb09bf1c |
563 | #ifdef FWHACK |
32874aea |
564 | if (st->len == 0x52656d6f) { /* "Remo"te server has closed ... */ |
565 | st->len = 0x300; /* big enough to carry to end */ |
fb09bf1c |
566 | } |
567 | #endif |
374330e2 |
568 | |
57476f6b |
569 | st->pad = 8 - (st->len % 8); |
570 | st->biglen = st->len + st->pad; |
571 | pktin.length = st->len - 5; |
fb09bf1c |
572 | |
57476f6b |
573 | if (pktin.maxlen < st->biglen) { |
574 | pktin.maxlen = st->biglen; |
32874aea |
575 | pktin.data = (pktin.data == NULL ? smalloc(st->biglen + APIEXTRA) : |
576 | srealloc(pktin.data, st->biglen + APIEXTRA)); |
fb09bf1c |
577 | if (!pktin.data) |
578 | fatalbox("Out of memory"); |
579 | } |
374330e2 |
580 | |
57476f6b |
581 | st->to_read = st->biglen; |
582 | st->p = pktin.data; |
583 | while (st->to_read > 0) { |
32874aea |
584 | st->chunk = st->to_read; |
fb09bf1c |
585 | while ((*datalen) == 0) |
57476f6b |
586 | crReturn(st->to_read); |
587 | if (st->chunk > (*datalen)) |
588 | st->chunk = (*datalen); |
589 | memcpy(st->p, *data, st->chunk); |
590 | *data += st->chunk; |
591 | *datalen -= st->chunk; |
592 | st->p += st->chunk; |
593 | st->to_read -= st->chunk; |
fb09bf1c |
594 | } |
374330e2 |
595 | |
fb09bf1c |
596 | if (cipher) |
57476f6b |
597 | cipher->decrypt(pktin.data, st->biglen); |
765c4200 |
598 | #ifdef DUMP_PACKETS |
599 | debug(("Got packet len=%d pad=%d\n", st->len, st->pad)); |
600 | dmemdump(pktin.data, st->biglen); |
698a5108 |
601 | #endif |
374330e2 |
602 | |
32874aea |
603 | st->realcrc = crc32(pktin.data, st->biglen - 4); |
604 | st->gotcrc = GET_32BIT(pktin.data + st->biglen - 4); |
57476f6b |
605 | if (st->gotcrc != st->realcrc) { |
8d5de777 |
606 | bombout(("Incorrect CRC received on packet")); |
32874aea |
607 | crReturn(0); |
fb09bf1c |
608 | } |
572f871e |
609 | |
4ba9b64b |
610 | pktin.body = pktin.data + st->pad + 1; |
611 | |
612 | if (ssh1_compressing) { |
613 | unsigned char *decompblk; |
614 | int decomplen; |
765c4200 |
615 | #ifdef DUMP_PACKETS |
616 | debug(("Packet payload pre-decompression:\n")); |
32874aea |
617 | dmemdump(pktin.body - 1, pktin.length + 1); |
4ba9b64b |
618 | #endif |
32874aea |
619 | zlib_decompress_block(pktin.body - 1, pktin.length + 1, |
4ba9b64b |
620 | &decompblk, &decomplen); |
621 | |
622 | if (pktin.maxlen < st->pad + decomplen) { |
623 | pktin.maxlen = st->pad + decomplen; |
32874aea |
624 | pktin.data = srealloc(pktin.data, pktin.maxlen + APIEXTRA); |
625 | pktin.body = pktin.data + st->pad + 1; |
4ba9b64b |
626 | if (!pktin.data) |
627 | fatalbox("Out of memory"); |
628 | } |
629 | |
32874aea |
630 | memcpy(pktin.body - 1, decompblk, decomplen); |
dcbde236 |
631 | sfree(decompblk); |
32874aea |
632 | pktin.length = decomplen - 1; |
765c4200 |
633 | #ifdef DUMP_PACKETS |
634 | debug(("Packet payload post-decompression:\n")); |
32874aea |
635 | dmemdump(pktin.body - 1, pktin.length + 1); |
4ba9b64b |
636 | #endif |
637 | } |
638 | |
e5574168 |
639 | if (pktin.type == SSH1_SMSG_STDOUT_DATA || |
32874aea |
640 | pktin.type == SSH1_SMSG_STDERR_DATA || |
641 | pktin.type == SSH1_MSG_DEBUG || |
642 | pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE || |
643 | pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) { |
fb09bf1c |
644 | long strlen = GET_32BIT(pktin.body); |
8d5de777 |
645 | if (strlen + 4 != pktin.length) { |
646 | bombout(("Received data packet with bogus string length")); |
32874aea |
647 | crReturn(0); |
648 | } |
fb09bf1c |
649 | } |
650 | |
4ba9b64b |
651 | pktin.type = pktin.body[-1]; |
652 | |
e5574168 |
653 | if (pktin.type == SSH1_MSG_DEBUG) { |
fb09bf1c |
654 | /* log debug message */ |
655 | char buf[80]; |
656 | int strlen = GET_32BIT(pktin.body); |
657 | strcpy(buf, "Remote: "); |
32874aea |
658 | if (strlen > 70) |
659 | strlen = 70; |
660 | memcpy(buf + 8, pktin.body + 4, strlen); |
661 | buf[8 + strlen] = '\0'; |
fb09bf1c |
662 | logevent(buf); |
663 | goto next_packet; |
e5574168 |
664 | } else if (pktin.type == SSH1_MSG_IGNORE) { |
fb09bf1c |
665 | /* do nothing */ |
666 | goto next_packet; |
667 | } |
668 | |
38c4a8da |
669 | if (pktin.type == SSH1_MSG_DISCONNECT) { |
670 | /* log reason code in disconnect message */ |
671 | char buf[256]; |
260f3dec |
672 | unsigned msglen = GET_32BIT(pktin.body); |
673 | unsigned nowlen; |
38c4a8da |
674 | strcpy(buf, "Remote sent disconnect: "); |
675 | nowlen = strlen(buf); |
32874aea |
676 | if (msglen > sizeof(buf) - nowlen - 1) |
677 | msglen = sizeof(buf) - nowlen - 1; |
678 | memcpy(buf + nowlen, pktin.body + 4, msglen); |
679 | buf[nowlen + msglen] = '\0'; |
38c4a8da |
680 | logevent(buf); |
681 | } |
682 | |
fb09bf1c |
683 | crFinish(0); |
684 | } |
685 | |
e5574168 |
686 | static int ssh2_rdpkt(unsigned char **data, int *datalen) |
687 | { |
960e736a |
688 | struct rdpkt2_state_tag *st = &rdpkt2_state; |
e5574168 |
689 | |
690 | crBegin; |
691 | |
32874aea |
692 | next_packet: |
e5574168 |
693 | pktin.type = 0; |
694 | pktin.length = 0; |
960e736a |
695 | if (sccipher) |
32874aea |
696 | st->cipherblk = sccipher->blksize; |
e5574168 |
697 | else |
32874aea |
698 | st->cipherblk = 8; |
960e736a |
699 | if (st->cipherblk < 8) |
32874aea |
700 | st->cipherblk = 8; |
960e736a |
701 | |
702 | if (pktin.maxlen < st->cipherblk) { |
703 | pktin.maxlen = st->cipherblk; |
32874aea |
704 | pktin.data = |
705 | (pktin.data == |
706 | NULL ? smalloc(st->cipherblk + |
707 | APIEXTRA) : srealloc(pktin.data, |
708 | st->cipherblk + |
709 | APIEXTRA)); |
e5574168 |
710 | if (!pktin.data) |
711 | fatalbox("Out of memory"); |
712 | } |
713 | |
714 | /* |
715 | * Acquire and decrypt the first block of the packet. This will |
716 | * contain the length and padding details. |
717 | */ |
32874aea |
718 | for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) { |
e5574168 |
719 | while ((*datalen) == 0) |
32874aea |
720 | crReturn(st->cipherblk - st->i); |
960e736a |
721 | pktin.data[st->i] = *(*data)++; |
32874aea |
722 | (*datalen)--; |
e5574168 |
723 | } |
724 | #ifdef FWHACK |
32874aea |
725 | if (!memcmp(pktin.data, "Remo", 4)) { /* "Remo"te server has closed ... */ |
726 | /* FIXME */ |
e5574168 |
727 | } |
728 | #endif |
729 | if (sccipher) |
32874aea |
730 | sccipher->decrypt(pktin.data, st->cipherblk); |
e5574168 |
731 | |
732 | /* |
733 | * Now get the length and padding figures. |
734 | */ |
960e736a |
735 | st->len = GET_32BIT(pktin.data); |
736 | st->pad = pktin.data[4]; |
e5574168 |
737 | |
738 | /* |
739 | * This enables us to deduce the payload length. |
740 | */ |
960e736a |
741 | st->payload = st->len - st->pad - 1; |
e5574168 |
742 | |
960e736a |
743 | pktin.length = st->payload + 5; |
e5574168 |
744 | |
745 | /* |
746 | * So now we can work out the total packet length. |
747 | */ |
960e736a |
748 | st->packetlen = st->len + 4; |
749 | st->maclen = scmac ? scmac->len : 0; |
e5574168 |
750 | |
751 | /* |
752 | * Adjust memory allocation if packet is too big. |
753 | */ |
32874aea |
754 | if (pktin.maxlen < st->packetlen + st->maclen) { |
755 | pktin.maxlen = st->packetlen + st->maclen; |
756 | pktin.data = |
757 | (pktin.data == |
758 | NULL ? smalloc(pktin.maxlen + APIEXTRA) : srealloc(pktin.data, |
759 | pktin.maxlen |
760 | + |
761 | APIEXTRA)); |
e5574168 |
762 | if (!pktin.data) |
763 | fatalbox("Out of memory"); |
764 | } |
765 | |
766 | /* |
767 | * Read and decrypt the remainder of the packet. |
768 | */ |
32874aea |
769 | for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen; |
770 | st->i++) { |
e5574168 |
771 | while ((*datalen) == 0) |
960e736a |
772 | crReturn(st->packetlen + st->maclen - st->i); |
773 | pktin.data[st->i] = *(*data)++; |
32874aea |
774 | (*datalen)--; |
e5574168 |
775 | } |
776 | /* Decrypt everything _except_ the MAC. */ |
777 | if (sccipher) |
32874aea |
778 | sccipher->decrypt(pktin.data + st->cipherblk, |
779 | st->packetlen - st->cipherblk); |
e5574168 |
780 | |
765c4200 |
781 | #ifdef DUMP_PACKETS |
782 | debug(("Got packet len=%d pad=%d\n", st->len, st->pad)); |
783 | dmemdump(pktin.data, st->packetlen); |
7cca0d81 |
784 | #endif |
d39f364a |
785 | |
e5574168 |
786 | /* |
787 | * Check the MAC. |
788 | */ |
32874aea |
789 | if (scmac |
790 | && !scmac->verify(pktin.data, st->len + 4, |
791 | st->incoming_sequence)) { |
8d5de777 |
792 | bombout(("Incorrect MAC received on packet")); |
32874aea |
793 | crReturn(0); |
8d5de777 |
794 | } |
32874aea |
795 | st->incoming_sequence++; /* whether or not we MACed */ |
e5574168 |
796 | |
4ba9b64b |
797 | /* |
798 | * Decompress packet payload. |
799 | */ |
800 | { |
801 | unsigned char *newpayload; |
802 | int newlen; |
32874aea |
803 | if (sccomp && sccomp->decompress(pktin.data + 5, pktin.length - 5, |
4ba9b64b |
804 | &newpayload, &newlen)) { |
32874aea |
805 | if (pktin.maxlen < newlen + 5) { |
806 | pktin.maxlen = newlen + 5; |
807 | pktin.data = |
808 | (pktin.data == |
809 | NULL ? smalloc(pktin.maxlen + |
810 | APIEXTRA) : srealloc(pktin.data, |
811 | pktin.maxlen + |
812 | APIEXTRA)); |
4ba9b64b |
813 | if (!pktin.data) |
814 | fatalbox("Out of memory"); |
815 | } |
816 | pktin.length = 5 + newlen; |
32874aea |
817 | memcpy(pktin.data + 5, newpayload, newlen); |
765c4200 |
818 | #ifdef DUMP_PACKETS |
819 | debug(("Post-decompression payload:\n")); |
32874aea |
820 | dmemdump(pktin.data + 5, newlen); |
4ba9b64b |
821 | #endif |
822 | |
dcbde236 |
823 | sfree(newpayload); |
4ba9b64b |
824 | } |
825 | } |
826 | |
e5574168 |
827 | pktin.savedpos = 6; |
828 | pktin.type = pktin.data[5]; |
e5574168 |
829 | |
7cca0d81 |
830 | if (pktin.type == SSH2_MSG_IGNORE || pktin.type == SSH2_MSG_DEBUG) |
32874aea |
831 | goto next_packet; /* FIXME: print DEBUG message */ |
e5574168 |
832 | |
38c4a8da |
833 | if (pktin.type == SSH2_MSG_DISCONNECT) { |
834 | /* log reason code in disconnect message */ |
835 | char buf[256]; |
32874aea |
836 | int reason = GET_32BIT(pktin.data + 6); |
837 | unsigned msglen = GET_32BIT(pktin.data + 10); |
260f3dec |
838 | unsigned nowlen; |
38c4a8da |
839 | if (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) { |
840 | sprintf(buf, "Received disconnect message (%s)", |
841 | ssh2_disconnect_reasons[reason]); |
842 | } else { |
32874aea |
843 | sprintf(buf, "Received disconnect message (unknown type %d)", |
844 | reason); |
38c4a8da |
845 | } |
846 | logevent(buf); |
847 | strcpy(buf, "Disconnection message text: "); |
848 | nowlen = strlen(buf); |
32874aea |
849 | if (msglen > sizeof(buf) - nowlen - 1) |
850 | msglen = sizeof(buf) - nowlen - 1; |
851 | memcpy(buf + nowlen, pktin.data + 14, msglen); |
852 | buf[nowlen + msglen] = '\0'; |
38c4a8da |
853 | logevent(buf); |
854 | } |
855 | |
e5574168 |
856 | crFinish(0); |
857 | } |
858 | |
32874aea |
859 | static void ssh1_pktout_size(int len) |
860 | { |
374330e2 |
861 | int pad, biglen; |
862 | |
863 | len += 5; /* type and CRC */ |
32874aea |
864 | pad = 8 - (len % 8); |
374330e2 |
865 | biglen = len + pad; |
866 | |
32874aea |
867 | pktout.length = len - 5; |
374330e2 |
868 | if (pktout.maxlen < biglen) { |
869 | pktout.maxlen = biglen; |
8f203108 |
870 | #ifdef MSCRYPTOAPI |
fb09bf1c |
871 | /* Allocate enough buffer space for extra block |
8f203108 |
872 | * for MS CryptEncrypt() */ |
32874aea |
873 | pktout.data = (pktout.data == NULL ? smalloc(biglen + 12) : |
874 | srealloc(pktout.data, biglen + 12)); |
8f203108 |
875 | #else |
32874aea |
876 | pktout.data = (pktout.data == NULL ? smalloc(biglen + 4) : |
877 | srealloc(pktout.data, biglen + 4)); |
8f203108 |
878 | #endif |
374330e2 |
879 | if (!pktout.data) |
880 | fatalbox("Out of memory"); |
881 | } |
32874aea |
882 | pktout.body = pktout.data + 4 + pad + 1; |
4ba9b64b |
883 | } |
374330e2 |
884 | |
32874aea |
885 | static void s_wrpkt_start(int type, int len) |
886 | { |
4ba9b64b |
887 | ssh1_pktout_size(len); |
374330e2 |
888 | pktout.type = type; |
374330e2 |
889 | } |
890 | |
32874aea |
891 | static int s_wrpkt_prepare(void) |
892 | { |
374330e2 |
893 | int pad, len, biglen, i; |
894 | unsigned long crc; |
895 | |
4ba9b64b |
896 | pktout.body[-1] = pktout.type; |
897 | |
765c4200 |
898 | #ifdef DUMP_PACKETS |
7d503c31 |
899 | debug(("Packet payload pre-compression:\n")); |
32874aea |
900 | dmemdump(pktout.body - 1, pktout.length + 1); |
7d503c31 |
901 | #endif |
902 | |
4ba9b64b |
903 | if (ssh1_compressing) { |
904 | unsigned char *compblk; |
905 | int complen; |
32874aea |
906 | zlib_compress_block(pktout.body - 1, pktout.length + 1, |
4ba9b64b |
907 | &compblk, &complen); |
32874aea |
908 | ssh1_pktout_size(complen - 1); |
909 | memcpy(pktout.body - 1, compblk, complen); |
dcbde236 |
910 | sfree(compblk); |
765c4200 |
911 | #ifdef DUMP_PACKETS |
4ba9b64b |
912 | debug(("Packet payload post-compression:\n")); |
32874aea |
913 | dmemdump(pktout.body - 1, pktout.length + 1); |
4ba9b64b |
914 | #endif |
915 | } |
916 | |
374330e2 |
917 | len = pktout.length + 5; /* type and CRC */ |
32874aea |
918 | pad = 8 - (len % 8); |
374330e2 |
919 | biglen = len + pad; |
920 | |
32874aea |
921 | for (i = 0; i < pad; i++) |
922 | pktout.data[i + 4] = random_byte(); |
923 | crc = crc32(pktout.data + 4, biglen - 4); |
924 | PUT_32BIT(pktout.data + biglen, crc); |
fb09bf1c |
925 | PUT_32BIT(pktout.data, len); |
374330e2 |
926 | |
765c4200 |
927 | #ifdef DUMP_PACKETS |
32874aea |
928 | debug(("Sending packet len=%d\n", biglen + 4)); |
929 | dmemdump(pktout.data, biglen + 4); |
698a5108 |
930 | #endif |
374330e2 |
931 | if (cipher) |
32874aea |
932 | cipher->encrypt(pktout.data + 4, biglen); |
374330e2 |
933 | |
32874aea |
934 | return biglen + 4; |
39065bed |
935 | } |
936 | |
32874aea |
937 | static void s_wrpkt(void) |
938 | { |
39065bed |
939 | int len; |
940 | len = s_wrpkt_prepare(); |
941 | sk_write(s, pktout.data, len); |
942 | } |
943 | |
32874aea |
944 | static void s_wrpkt_defer(void) |
945 | { |
39065bed |
946 | int len; |
947 | len = s_wrpkt_prepare(); |
948 | if (deferred_len + len > deferred_size) { |
32874aea |
949 | deferred_size = deferred_len + len + 128; |
950 | deferred_send_data = srealloc(deferred_send_data, deferred_size); |
39065bed |
951 | } |
32874aea |
952 | memcpy(deferred_send_data + deferred_len, pktout.data, len); |
39065bed |
953 | deferred_len += len; |
374330e2 |
954 | } |
955 | |
fb09bf1c |
956 | /* |
39065bed |
957 | * Construct a packet with the specified contents. |
fb09bf1c |
958 | */ |
39065bed |
959 | static void construct_packet(int pkttype, va_list ap1, va_list ap2) |
fb09bf1c |
960 | { |
fb09bf1c |
961 | unsigned char *p, *argp, argchar; |
962 | unsigned long argint; |
963 | int pktlen, argtype, arglen; |
7cca0d81 |
964 | Bignum bn; |
fb09bf1c |
965 | |
966 | pktlen = 0; |
39065bed |
967 | while ((argtype = va_arg(ap1, int)) != PKT_END) { |
fb09bf1c |
968 | switch (argtype) { |
969 | case PKT_INT: |
39065bed |
970 | (void) va_arg(ap1, int); |
fb09bf1c |
971 | pktlen += 4; |
972 | break; |
973 | case PKT_CHAR: |
39065bed |
974 | (void) va_arg(ap1, char); |
fb09bf1c |
975 | pktlen++; |
976 | break; |
977 | case PKT_DATA: |
39065bed |
978 | (void) va_arg(ap1, unsigned char *); |
979 | arglen = va_arg(ap1, int); |
fb09bf1c |
980 | pktlen += arglen; |
981 | break; |
982 | case PKT_STR: |
39065bed |
983 | argp = va_arg(ap1, unsigned char *); |
fb09bf1c |
984 | arglen = strlen(argp); |
985 | pktlen += 4 + arglen; |
986 | break; |
7cca0d81 |
987 | case PKT_BIGNUM: |
39065bed |
988 | bn = va_arg(ap1, Bignum); |
32874aea |
989 | pktlen += ssh1_bignum_length(bn); |
7cca0d81 |
990 | break; |
fb09bf1c |
991 | default: |
992 | assert(0); |
993 | } |
994 | } |
fb09bf1c |
995 | |
996 | s_wrpkt_start(pkttype, pktlen); |
997 | p = pktout.body; |
998 | |
39065bed |
999 | while ((argtype = va_arg(ap2, int)) != PKT_END) { |
fb09bf1c |
1000 | switch (argtype) { |
1001 | case PKT_INT: |
39065bed |
1002 | argint = va_arg(ap2, int); |
fb09bf1c |
1003 | PUT_32BIT(p, argint); |
1004 | p += 4; |
1005 | break; |
1006 | case PKT_CHAR: |
39065bed |
1007 | argchar = va_arg(ap2, unsigned char); |
fb09bf1c |
1008 | *p = argchar; |
1009 | p++; |
1010 | break; |
1011 | case PKT_DATA: |
39065bed |
1012 | argp = va_arg(ap2, unsigned char *); |
1013 | arglen = va_arg(ap2, int); |
fb09bf1c |
1014 | memcpy(p, argp, arglen); |
1015 | p += arglen; |
1016 | break; |
1017 | case PKT_STR: |
39065bed |
1018 | argp = va_arg(ap2, unsigned char *); |
fb09bf1c |
1019 | arglen = strlen(argp); |
1020 | PUT_32BIT(p, arglen); |
1021 | memcpy(p + 4, argp, arglen); |
1022 | p += 4 + arglen; |
1023 | break; |
7cca0d81 |
1024 | case PKT_BIGNUM: |
39065bed |
1025 | bn = va_arg(ap2, Bignum); |
32874aea |
1026 | p += ssh1_write_bignum(p, bn); |
7cca0d81 |
1027 | break; |
fb09bf1c |
1028 | } |
1029 | } |
39065bed |
1030 | } |
fb09bf1c |
1031 | |
32874aea |
1032 | static void send_packet(int pkttype, ...) |
1033 | { |
39065bed |
1034 | va_list ap1, ap2; |
1035 | va_start(ap1, pkttype); |
1036 | va_start(ap2, pkttype); |
1037 | construct_packet(pkttype, ap1, ap2); |
fb09bf1c |
1038 | s_wrpkt(); |
1039 | } |
1040 | |
32874aea |
1041 | static void defer_packet(int pkttype, ...) |
1042 | { |
39065bed |
1043 | va_list ap1, ap2; |
1044 | va_start(ap1, pkttype); |
1045 | va_start(ap2, pkttype); |
1046 | construct_packet(pkttype, ap1, ap2); |
1047 | s_wrpkt_defer(); |
1048 | } |
1049 | |
32874aea |
1050 | static int ssh_versioncmp(char *a, char *b) |
1051 | { |
9697bfd2 |
1052 | char *ae, *be; |
1053 | unsigned long av, bv; |
1054 | |
43aa02a7 |
1055 | av = strtoul(a, &ae, 10); |
1056 | bv = strtoul(b, &be, 10); |
32874aea |
1057 | if (av != bv) |
1058 | return (av < bv ? -1 : +1); |
1059 | if (*ae == '.') |
1060 | ae++; |
1061 | if (*be == '.') |
1062 | be++; |
43aa02a7 |
1063 | av = strtoul(ae, &ae, 10); |
1064 | bv = strtoul(be, &be, 10); |
32874aea |
1065 | if (av != bv) |
1066 | return (av < bv ? -1 : +1); |
9697bfd2 |
1067 | return 0; |
1068 | } |
1069 | |
e5574168 |
1070 | |
1071 | /* |
a92dd380 |
1072 | * Utility routines for putting an SSH-protocol `string' and |
1073 | * `uint32' into a SHA state. |
e5574168 |
1074 | */ |
1075 | #include <stdio.h> |
32874aea |
1076 | static void sha_string(SHA_State * s, void *str, int len) |
1077 | { |
e5574168 |
1078 | unsigned char lenblk[4]; |
e5574168 |
1079 | PUT_32BIT(lenblk, len); |
e5574168 |
1080 | SHA_Bytes(s, lenblk, 4); |
e5574168 |
1081 | SHA_Bytes(s, str, len); |
1082 | } |
1083 | |
32874aea |
1084 | static void sha_uint32(SHA_State * s, unsigned i) |
1085 | { |
a92dd380 |
1086 | unsigned char intblk[4]; |
1087 | PUT_32BIT(intblk, i); |
1088 | SHA_Bytes(s, intblk, 4); |
1089 | } |
1090 | |
7cca0d81 |
1091 | /* |
1092 | * SSH2 packet construction functions. |
1093 | */ |
32874aea |
1094 | static void ssh2_pkt_ensure(int length) |
1095 | { |
783415f8 |
1096 | if (pktout.maxlen < length) { |
32874aea |
1097 | pktout.maxlen = length + 256; |
1098 | pktout.data = |
1099 | (pktout.data == |
1100 | NULL ? smalloc(pktout.maxlen + |
1101 | APIEXTRA) : srealloc(pktout.data, |
1102 | pktout.maxlen + |
1103 | APIEXTRA)); |
1104 | if (!pktout.data) |
1105 | fatalbox("Out of memory"); |
7cca0d81 |
1106 | } |
783415f8 |
1107 | } |
32874aea |
1108 | static void ssh2_pkt_adddata(void *data, int len) |
1109 | { |
783415f8 |
1110 | pktout.length += len; |
1111 | ssh2_pkt_ensure(pktout.length); |
32874aea |
1112 | memcpy(pktout.data + pktout.length - len, data, len); |
7cca0d81 |
1113 | } |
32874aea |
1114 | static void ssh2_pkt_addbyte(unsigned char byte) |
1115 | { |
7cca0d81 |
1116 | ssh2_pkt_adddata(&byte, 1); |
1117 | } |
32874aea |
1118 | static void ssh2_pkt_init(int pkt_type) |
1119 | { |
7cca0d81 |
1120 | pktout.length = 5; |
32874aea |
1121 | ssh2_pkt_addbyte((unsigned char) pkt_type); |
7cca0d81 |
1122 | } |
32874aea |
1123 | static void ssh2_pkt_addbool(unsigned char value) |
1124 | { |
7cca0d81 |
1125 | ssh2_pkt_adddata(&value, 1); |
1126 | } |
32874aea |
1127 | static void ssh2_pkt_adduint32(unsigned long value) |
1128 | { |
7cca0d81 |
1129 | unsigned char x[4]; |
1130 | PUT_32BIT(x, value); |
1131 | ssh2_pkt_adddata(x, 4); |
1132 | } |
32874aea |
1133 | static void ssh2_pkt_addstring_start(void) |
1134 | { |
7cca0d81 |
1135 | ssh2_pkt_adduint32(0); |
1136 | pktout.savedpos = pktout.length; |
1137 | } |
32874aea |
1138 | static void ssh2_pkt_addstring_str(char *data) |
1139 | { |
7cca0d81 |
1140 | ssh2_pkt_adddata(data, strlen(data)); |
1141 | PUT_32BIT(pktout.data + pktout.savedpos - 4, |
32874aea |
1142 | pktout.length - pktout.savedpos); |
7cca0d81 |
1143 | } |
32874aea |
1144 | static void ssh2_pkt_addstring_data(char *data, int len) |
1145 | { |
7cca0d81 |
1146 | ssh2_pkt_adddata(data, len); |
1147 | PUT_32BIT(pktout.data + pktout.savedpos - 4, |
32874aea |
1148 | pktout.length - pktout.savedpos); |
7cca0d81 |
1149 | } |
32874aea |
1150 | static void ssh2_pkt_addstring(char *data) |
1151 | { |
7cca0d81 |
1152 | ssh2_pkt_addstring_start(); |
1153 | ssh2_pkt_addstring_str(data); |
1154 | } |
32874aea |
1155 | static char *ssh2_mpint_fmt(Bignum b, int *len) |
1156 | { |
7cca0d81 |
1157 | unsigned char *p; |
32874aea |
1158 | int i, n = (bignum_bitcount(b) + 7) / 8; |
3709bfe9 |
1159 | p = smalloc(n + 1); |
7cca0d81 |
1160 | if (!p) |
32874aea |
1161 | fatalbox("out of memory"); |
7cca0d81 |
1162 | p[0] = 0; |
3709bfe9 |
1163 | for (i = 1; i <= n; i++) |
32874aea |
1164 | p[i] = bignum_byte(b, n - i); |
7cca0d81 |
1165 | i = 0; |
32874aea |
1166 | while (i <= n && p[i] == 0 && (p[i + 1] & 0x80) == 0) |
1167 | i++; |
1168 | memmove(p, p + i, n + 1 - i); |
1169 | *len = n + 1 - i; |
7cca0d81 |
1170 | return p; |
1171 | } |
32874aea |
1172 | static void ssh2_pkt_addmp(Bignum b) |
1173 | { |
7cca0d81 |
1174 | unsigned char *p; |
1175 | int len; |
1176 | p = ssh2_mpint_fmt(b, &len); |
1177 | ssh2_pkt_addstring_start(); |
1178 | ssh2_pkt_addstring_data(p, len); |
dcbde236 |
1179 | sfree(p); |
7cca0d81 |
1180 | } |
b185170a |
1181 | |
1182 | /* |
1183 | * Construct an SSH2 final-form packet: compress it, encrypt it, |
1184 | * put the MAC on it. Final packet, ready to be sent, is stored in |
1185 | * pktout.data. Total length is returned. |
1186 | */ |
32874aea |
1187 | static int ssh2_pkt_construct(void) |
1188 | { |
7cca0d81 |
1189 | int cipherblk, maclen, padding, i; |
1190 | static unsigned long outgoing_sequence = 0; |
1191 | |
1192 | /* |
4ba9b64b |
1193 | * Compress packet payload. |
1194 | */ |
765c4200 |
1195 | #ifdef DUMP_PACKETS |
1196 | debug(("Pre-compression payload:\n")); |
32874aea |
1197 | dmemdump(pktout.data + 5, pktout.length - 5); |
4ba9b64b |
1198 | #endif |
1199 | { |
1200 | unsigned char *newpayload; |
1201 | int newlen; |
32874aea |
1202 | if (cscomp && cscomp->compress(pktout.data + 5, pktout.length - 5, |
4ba9b64b |
1203 | &newpayload, &newlen)) { |
1204 | pktout.length = 5; |
1205 | ssh2_pkt_adddata(newpayload, newlen); |
dcbde236 |
1206 | sfree(newpayload); |
4ba9b64b |
1207 | } |
1208 | } |
1209 | |
1210 | /* |
7cca0d81 |
1211 | * Add padding. At least four bytes, and must also bring total |
1212 | * length (minus MAC) up to a multiple of the block size. |
1213 | */ |
32874aea |
1214 | cipherblk = cscipher ? cscipher->blksize : 8; /* block size */ |
1215 | cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */ |
7cca0d81 |
1216 | padding = 4; |
32874aea |
1217 | padding += |
1218 | (cipherblk - (pktout.length + padding) % cipherblk) % cipherblk; |
783415f8 |
1219 | maclen = csmac ? csmac->len : 0; |
1220 | ssh2_pkt_ensure(pktout.length + padding + maclen); |
7cca0d81 |
1221 | pktout.data[4] = padding; |
1222 | for (i = 0; i < padding; i++) |
32874aea |
1223 | pktout.data[pktout.length + i] = random_byte(); |
7cca0d81 |
1224 | PUT_32BIT(pktout.data, pktout.length + padding - 4); |
1225 | if (csmac) |
32874aea |
1226 | csmac->generate(pktout.data, pktout.length + padding, |
1227 | outgoing_sequence); |
1228 | outgoing_sequence++; /* whether or not we MACed */ |
7cca0d81 |
1229 | |
765c4200 |
1230 | #ifdef DUMP_PACKETS |
32874aea |
1231 | debug(("Sending packet len=%d\n", pktout.length + padding)); |
1232 | dmemdump(pktout.data, pktout.length + padding); |
7cca0d81 |
1233 | #endif |
1234 | |
1235 | if (cscipher) |
32874aea |
1236 | cscipher->encrypt(pktout.data, pktout.length + padding); |
7cca0d81 |
1237 | |
b185170a |
1238 | /* Ready-to-send packet starts at pktout.data. We return length. */ |
1239 | return pktout.length + padding + maclen; |
1240 | } |
1241 | |
1242 | /* |
1243 | * Construct and send an SSH2 packet immediately. |
1244 | */ |
32874aea |
1245 | static void ssh2_pkt_send(void) |
1246 | { |
b185170a |
1247 | int len = ssh2_pkt_construct(); |
1248 | sk_write(s, pktout.data, len); |
1249 | } |
1250 | |
1251 | /* |
1252 | * Construct an SSH2 packet and add it to a deferred data block. |
1253 | * Useful for sending multiple packets in a single sk_write() call, |
1254 | * to prevent a traffic-analysing listener from being able to work |
1255 | * out the length of any particular packet (such as the password |
1256 | * packet). |
1257 | * |
1258 | * Note that because SSH2 sequence-numbers its packets, this can |
1259 | * NOT be used as an m4-style `defer' allowing packets to be |
1260 | * constructed in one order and sent in another. |
1261 | */ |
32874aea |
1262 | static void ssh2_pkt_defer(void) |
1263 | { |
b185170a |
1264 | int len = ssh2_pkt_construct(); |
1265 | if (deferred_len + len > deferred_size) { |
32874aea |
1266 | deferred_size = deferred_len + len + 128; |
1267 | deferred_send_data = srealloc(deferred_send_data, deferred_size); |
b185170a |
1268 | } |
32874aea |
1269 | memcpy(deferred_send_data + deferred_len, pktout.data, len); |
b185170a |
1270 | deferred_len += len; |
1271 | } |
1272 | |
1273 | /* |
1274 | * Send the whole deferred data block constructed by |
39065bed |
1275 | * ssh2_pkt_defer() or SSH1's defer_packet(). |
b185170a |
1276 | */ |
32874aea |
1277 | static void ssh_pkt_defersend(void) |
1278 | { |
b185170a |
1279 | sk_write(s, deferred_send_data, deferred_len); |
1280 | deferred_len = deferred_size = 0; |
1281 | sfree(deferred_send_data); |
1282 | deferred_send_data = NULL; |
7cca0d81 |
1283 | } |
1284 | |
1285 | #if 0 |
32874aea |
1286 | void bndebug(char *string, Bignum b) |
1287 | { |
7cca0d81 |
1288 | unsigned char *p; |
1289 | int i, len; |
1290 | p = ssh2_mpint_fmt(b, &len); |
1291 | debug(("%s", string)); |
1292 | for (i = 0; i < len; i++) |
32874aea |
1293 | debug((" %02x", p[i])); |
765c4200 |
1294 | debug(("\n")); |
dcbde236 |
1295 | sfree(p); |
7cca0d81 |
1296 | } |
1297 | #endif |
1298 | |
32874aea |
1299 | static void sha_mpint(SHA_State * s, Bignum b) |
1300 | { |
7cca0d81 |
1301 | unsigned char *p; |
1302 | int len; |
1303 | p = ssh2_mpint_fmt(b, &len); |
1304 | sha_string(s, p, len); |
dcbde236 |
1305 | sfree(p); |
7cca0d81 |
1306 | } |
1307 | |
1308 | /* |
1309 | * SSH2 packet decode functions. |
1310 | */ |
32874aea |
1311 | static unsigned long ssh2_pkt_getuint32(void) |
1312 | { |
7cca0d81 |
1313 | unsigned long value; |
1314 | if (pktin.length - pktin.savedpos < 4) |
32874aea |
1315 | return 0; /* arrgh, no way to decline (FIXME?) */ |
1316 | value = GET_32BIT(pktin.data + pktin.savedpos); |
7cca0d81 |
1317 | pktin.savedpos += 4; |
1318 | return value; |
1319 | } |
32874aea |
1320 | static int ssh2_pkt_getbool(void) |
1321 | { |
65a22376 |
1322 | unsigned long value; |
1323 | if (pktin.length - pktin.savedpos < 1) |
32874aea |
1324 | return 0; /* arrgh, no way to decline (FIXME?) */ |
65a22376 |
1325 | value = pktin.data[pktin.savedpos] != 0; |
1326 | pktin.savedpos++; |
1327 | return value; |
1328 | } |
32874aea |
1329 | static void ssh2_pkt_getstring(char **p, int *length) |
1330 | { |
7cca0d81 |
1331 | *p = NULL; |
1332 | if (pktin.length - pktin.savedpos < 4) |
32874aea |
1333 | return; |
1334 | *length = GET_32BIT(pktin.data + pktin.savedpos); |
7cca0d81 |
1335 | pktin.savedpos += 4; |
1336 | if (pktin.length - pktin.savedpos < *length) |
32874aea |
1337 | return; |
1338 | *p = pktin.data + pktin.savedpos; |
7cca0d81 |
1339 | pktin.savedpos += *length; |
1340 | } |
32874aea |
1341 | static Bignum ssh2_pkt_getmp(void) |
1342 | { |
7cca0d81 |
1343 | char *p; |
3709bfe9 |
1344 | int length; |
7cca0d81 |
1345 | Bignum b; |
1346 | |
1347 | ssh2_pkt_getstring(&p, &length); |
1348 | if (!p) |
32874aea |
1349 | return NULL; |
8d5de777 |
1350 | if (p[0] & 0x80) { |
32874aea |
1351 | bombout(("internal error: Can't handle negative mpints")); |
1352 | return NULL; |
8d5de777 |
1353 | } |
3709bfe9 |
1354 | b = bignum_from_bytes(p, length); |
7cca0d81 |
1355 | return b; |
1356 | } |
1357 | |
7d503c31 |
1358 | /* |
1359 | * Examine the remote side's version string and compare it against |
1360 | * a list of known buggy implementations. |
1361 | */ |
32874aea |
1362 | static void ssh_detect_bugs(char *vstring) |
1363 | { |
1364 | char *imp; /* pointer to implementation part */ |
7d503c31 |
1365 | imp = vstring; |
1366 | imp += strcspn(imp, "-"); |
32874aea |
1367 | if (*imp) |
1368 | imp++; |
7d503c31 |
1369 | imp += strcspn(imp, "-"); |
32874aea |
1370 | if (*imp) |
1371 | imp++; |
7d503c31 |
1372 | |
1373 | ssh_remote_bugs = 0; |
1374 | |
1375 | if (!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") || |
32874aea |
1376 | !strcmp(imp, "1.2.20") || !strcmp(imp, "1.2.21") || |
1377 | !strcmp(imp, "1.2.22")) { |
1378 | /* |
1379 | * These versions don't support SSH1_MSG_IGNORE, so we have |
1380 | * to use a different defence against password length |
1381 | * sniffing. |
1382 | */ |
1383 | ssh_remote_bugs |= BUG_CHOKES_ON_SSH1_IGNORE; |
1384 | logevent("We believe remote version has SSH1 ignore bug"); |
7d503c31 |
1385 | } |
1386 | |
1387 | if (!strncmp(imp, "2.1.0", 5) || !strncmp(imp, "2.0.", 4) || |
32874aea |
1388 | !strncmp(imp, "2.2.0", 5) || !strncmp(imp, "2.3.0", 5) || |
1389 | !strncmp(imp, "2.1 ", 4)) { |
1390 | /* |
1391 | * These versions have the HMAC bug. |
1392 | */ |
1393 | ssh_remote_bugs |= BUG_SSH2_HMAC; |
1394 | logevent("We believe remote version has SSH2 HMAC bug"); |
7d503c31 |
1395 | } |
1396 | } |
1397 | |
32874aea |
1398 | static int do_ssh_init(unsigned char c) |
1399 | { |
2d466ffd |
1400 | static int vslen; |
8df7a775 |
1401 | static char version[10]; |
50526e47 |
1402 | static char *vstring; |
1403 | static int vstrsize; |
1404 | static char *vlog; |
8df7a775 |
1405 | static int i; |
374330e2 |
1406 | |
8df7a775 |
1407 | crBegin; |
1408 | |
1409 | /* Search for the string "SSH-" in the input. */ |
374330e2 |
1410 | i = 0; |
8df7a775 |
1411 | while (1) { |
1412 | static const int transS[] = { 1, 2, 2, 1 }; |
1413 | static const int transH[] = { 0, 0, 3, 0 }; |
1414 | static const int transminus[] = { 0, 0, 0, -1 }; |
32874aea |
1415 | if (c == 'S') |
1416 | i = transS[i]; |
1417 | else if (c == 'H') |
1418 | i = transH[i]; |
1419 | else if (c == '-') |
1420 | i = transminus[i]; |
1421 | else |
1422 | i = 0; |
8df7a775 |
1423 | if (i < 0) |
1424 | break; |
1425 | crReturn(1); /* get another character */ |
374330e2 |
1426 | } |
8df7a775 |
1427 | |
50526e47 |
1428 | vstring = smalloc(16); |
1429 | vstrsize = 16; |
c5e9c988 |
1430 | strcpy(vstring, "SSH-"); |
50526e47 |
1431 | vslen = 4; |
374330e2 |
1432 | i = 0; |
1433 | while (1) { |
8df7a775 |
1434 | crReturn(1); /* get another char */ |
32874aea |
1435 | if (vslen >= vstrsize - 1) { |
1436 | vstrsize += 16; |
1437 | vstring = srealloc(vstring, vstrsize); |
1438 | } |
1439 | vstring[vslen++] = c; |
374330e2 |
1440 | if (i >= 0) { |
1441 | if (c == '-') { |
1442 | version[i] = '\0'; |
1443 | i = -1; |
32874aea |
1444 | } else if (i < sizeof(version) - 1) |
374330e2 |
1445 | version[i++] = c; |
32874aea |
1446 | } else if (c == '\n') |
374330e2 |
1447 | break; |
1448 | } |
1449 | |
db7d555c |
1450 | ssh_agentfwd_enabled = FALSE; |
960e736a |
1451 | rdpkt2_state.incoming_sequence = 0; |
1452 | |
50526e47 |
1453 | vstring[vslen] = 0; |
9275ca8a |
1454 | vlog = smalloc(20 + vslen); |
c5e9c988 |
1455 | sprintf(vlog, "Server version: %s", vstring); |
7d503c31 |
1456 | ssh_detect_bugs(vstring); |
c5e9c988 |
1457 | vlog[strcspn(vlog, "\r\n")] = '\0'; |
1458 | logevent(vlog); |
9275ca8a |
1459 | sfree(vlog); |
c5e9c988 |
1460 | |
adf799dd |
1461 | /* |
1462 | * Server version "1.99" means we can choose whether we use v1 |
1463 | * or v2 protocol. Choice is based on cfg.sshprot. |
1464 | */ |
1465 | if (ssh_versioncmp(version, cfg.sshprot == 1 ? "2.0" : "1.99") >= 0) { |
32874aea |
1466 | /* |
1467 | * This is a v2 server. Begin v2 protocol. |
1468 | */ |
1469 | char verstring[80], vlog[100]; |
1470 | sprintf(verstring, "SSH-2.0-%s", sshver); |
1471 | SHA_Init(&exhashbase); |
1472 | /* |
1473 | * Hash our version string and their version string. |
1474 | */ |
1475 | sha_string(&exhashbase, verstring, strlen(verstring)); |
1476 | sha_string(&exhashbase, vstring, strcspn(vstring, "\r\n")); |
1477 | sprintf(vlog, "We claim version: %s", verstring); |
1478 | logevent(vlog); |
1479 | strcat(verstring, "\n"); |
1480 | logevent("Using SSH protocol version 2"); |
1481 | sk_write(s, verstring, strlen(verstring)); |
1482 | ssh_protocol = ssh2_protocol; |
1483 | ssh_version = 2; |
1484 | s_rdpkt = ssh2_rdpkt; |
e5574168 |
1485 | } else { |
32874aea |
1486 | /* |
1487 | * This is a v1 server. Begin v1 protocol. |
1488 | */ |
1489 | char verstring[80], vlog[100]; |
1490 | sprintf(verstring, "SSH-%s-%s", |
1491 | (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5"), |
1492 | sshver); |
1493 | sprintf(vlog, "We claim version: %s", verstring); |
1494 | logevent(vlog); |
1495 | strcat(verstring, "\n"); |
1496 | logevent("Using SSH protocol version 1"); |
1497 | sk_write(s, verstring, strlen(verstring)); |
1498 | ssh_protocol = ssh1_protocol; |
1499 | ssh_version = 1; |
1500 | s_rdpkt = ssh1_rdpkt; |
e5574168 |
1501 | } |
3687d221 |
1502 | ssh_state = SSH_STATE_BEFORE_SIZE; |
8df7a775 |
1503 | |
50526e47 |
1504 | sfree(vstring); |
50526e47 |
1505 | |
8df7a775 |
1506 | crFinish(0); |
1507 | } |
1508 | |
1509 | static void ssh_gotdata(unsigned char *data, int datalen) |
1510 | { |
1511 | crBegin; |
1512 | |
1513 | /* |
1514 | * To begin with, feed the characters one by one to the |
1515 | * protocol initialisation / selection function do_ssh_init(). |
1516 | * When that returns 0, we're done with the initial greeting |
1517 | * exchange and can move on to packet discipline. |
1518 | */ |
1519 | while (1) { |
1520 | int ret; |
1521 | if (datalen == 0) |
1522 | crReturnV; /* more data please */ |
1523 | ret = do_ssh_init(*data); |
32874aea |
1524 | data++; |
1525 | datalen--; |
8df7a775 |
1526 | if (ret == 0) |
1527 | break; |
1528 | } |
1529 | |
1530 | /* |
1531 | * We emerge from that loop when the initial negotiation is |
1532 | * over and we have selected an s_rdpkt function. Now pass |
1533 | * everything to s_rdpkt, and then pass the resulting packets |
1534 | * to the proper protocol handler. |
1535 | */ |
1536 | if (datalen == 0) |
1537 | crReturnV; |
1538 | while (1) { |
1539 | while (datalen > 0) { |
32874aea |
1540 | if (s_rdpkt(&data, &datalen) == 0) { |
8df7a775 |
1541 | ssh_protocol(NULL, 0, 1); |
1542 | if (ssh_state == SSH_STATE_CLOSED) { |
1543 | return; |
1544 | } |
1545 | } |
1546 | } |
1547 | crReturnV; |
1548 | } |
1549 | crFinishV; |
1550 | } |
1551 | |
32874aea |
1552 | static int ssh_closing(Plug plug, char *error_msg, int error_code, |
1553 | int calling_back) |
1554 | { |
7e78000d |
1555 | ssh_state = SSH_STATE_CLOSED; |
f3ab576e |
1556 | if (s) { |
1557 | sk_close(s); |
1558 | s = NULL; |
1559 | } |
7e78000d |
1560 | if (error_msg) { |
32874aea |
1561 | /* A socket error has occurred. */ |
1562 | connection_fatal(error_msg); |
7e78000d |
1563 | } else { |
1564 | /* Otherwise, the remote side closed the connection normally. */ |
8df7a775 |
1565 | } |
7e78000d |
1566 | return 0; |
1567 | } |
1568 | |
32874aea |
1569 | static int ssh_receive(Plug plug, int urgent, char *data, int len) |
1570 | { |
1571 | ssh_gotdata(data, len); |
3257deae |
1572 | if (ssh_state == SSH_STATE_CLOSED) { |
32874aea |
1573 | if (s) { |
1574 | sk_close(s); |
1575 | s = NULL; |
1576 | } |
1577 | return 0; |
3257deae |
1578 | } |
fef97f43 |
1579 | return 1; |
374330e2 |
1580 | } |
1581 | |
fb09bf1c |
1582 | /* |
8df7a775 |
1583 | * Connect to specified host and port. |
1584 | * Returns an error message, or NULL on success. |
6e1ebb76 |
1585 | * Also places the canonical host name into `realhost'. It must be |
1586 | * freed by the caller. |
8df7a775 |
1587 | */ |
1588 | static char *connect_to_host(char *host, int port, char **realhost) |
1589 | { |
7e78000d |
1590 | static struct plug_function_table fn_table = { |
1591 | ssh_closing, |
1592 | ssh_receive |
1593 | }, *fn_table_ptr = &fn_table; |
1594 | |
8df7a775 |
1595 | SockAddr addr; |
1596 | char *err; |
1597 | #ifdef FWHACK |
1598 | char *FWhost; |
1599 | int FWport; |
1600 | #endif |
1601 | |
32874aea |
1602 | savedhost = smalloc(1 + strlen(host)); |
8df7a775 |
1603 | if (!savedhost) |
1604 | fatalbox("Out of memory"); |
1605 | strcpy(savedhost, host); |
1606 | |
1607 | if (port < 0) |
1608 | port = 22; /* default ssh port */ |
1609 | savedport = port; |
1610 | |
1611 | #ifdef FWHACK |
1612 | FWhost = host; |
1613 | FWport = port; |
1614 | host = FWSTR; |
1615 | port = 23; |
1616 | #endif |
1617 | |
1618 | /* |
1619 | * Try to find host. |
1620 | */ |
1621 | addr = sk_namelookup(host, realhost); |
32874aea |
1622 | if ((err = sk_addr_error(addr))) |
8df7a775 |
1623 | return err; |
1624 | |
1625 | #ifdef FWHACK |
6e1ebb76 |
1626 | *realhost = strdup(FWhost); |
8df7a775 |
1627 | #endif |
1628 | |
1629 | /* |
1630 | * Open socket. |
1631 | */ |
7e78000d |
1632 | s = sk_new(addr, port, 0, 1, &fn_table_ptr); |
32874aea |
1633 | if ((err = sk_socket_error(s))) |
8df7a775 |
1634 | return err; |
1635 | |
1636 | #ifdef FWHACK |
1637 | sk_write(s, "connect ", 8); |
1638 | sk_write(s, FWhost, strlen(FWhost)); |
1639 | { |
1640 | char buf[20]; |
1641 | sprintf(buf, " %d\n", FWport); |
1642 | sk_write(s, buf, strlen(buf)); |
1643 | } |
1644 | #endif |
1645 | |
1646 | return NULL; |
1647 | } |
1648 | |
1649 | /* |
fb09bf1c |
1650 | * Handle the key exchange and user authentication phases. |
1651 | */ |
e5574168 |
1652 | static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) |
fb09bf1c |
1653 | { |
2d466ffd |
1654 | int i, j; |
1655 | static int len; |
1656 | static unsigned char *rsabuf, *keystr1, *keystr2; |
374330e2 |
1657 | unsigned char cookie[8]; |
1658 | struct RSAKey servkey, hostkey; |
1659 | struct MD5Context md5c; |
ccbfb941 |
1660 | static unsigned long supported_ciphers_mask, supported_auths_mask; |
7cca0d81 |
1661 | static int tried_publickey; |
1662 | static unsigned char session_id[16]; |
2d466ffd |
1663 | static int cipher_type; |
b585ec46 |
1664 | static char username[100]; |
374330e2 |
1665 | |
374330e2 |
1666 | crBegin; |
1667 | |
32874aea |
1668 | if (!ispkt) |
1669 | crWaitUntil(ispkt); |
374330e2 |
1670 | |
8d5de777 |
1671 | if (pktin.type != SSH1_SMSG_PUBLIC_KEY) { |
1672 | bombout(("Public key packet not received")); |
32874aea |
1673 | crReturn(0); |
8d5de777 |
1674 | } |
374330e2 |
1675 | |
c5e9c988 |
1676 | logevent("Received public keys"); |
374330e2 |
1677 | |
c5e9c988 |
1678 | memcpy(cookie, pktin.body, 8); |
374330e2 |
1679 | |
32874aea |
1680 | i = makekey(pktin.body + 8, &servkey, &keystr1, 0); |
1681 | j = makekey(pktin.body + 8 + i, &hostkey, &keystr2, 0); |
374330e2 |
1682 | |
c5e9c988 |
1683 | /* |
1c2a93c4 |
1684 | * Log the host key fingerprint. |
c5e9c988 |
1685 | */ |
c5e9c988 |
1686 | { |
1687 | char logmsg[80]; |
1c2a93c4 |
1688 | logevent("Host key fingerprint is:"); |
c5e9c988 |
1689 | strcpy(logmsg, " "); |
32874aea |
1690 | hostkey.comment = NULL; |
1691 | rsa_fingerprint(logmsg + strlen(logmsg), |
1692 | sizeof(logmsg) - strlen(logmsg), &hostkey); |
c5e9c988 |
1693 | logevent(logmsg); |
1694 | } |
1695 | |
32874aea |
1696 | ssh1_remote_protoflags = GET_32BIT(pktin.body + 8 + i + j); |
1697 | supported_ciphers_mask = GET_32BIT(pktin.body + 12 + i + j); |
1698 | supported_auths_mask = GET_32BIT(pktin.body + 16 + i + j); |
bea1ef5f |
1699 | |
32874aea |
1700 | ssh1_local_protoflags = |
1701 | ssh1_remote_protoflags & SSH1_PROTOFLAGS_SUPPORTED; |
b96dc54c |
1702 | ssh1_local_protoflags |= SSH1_PROTOFLAG_SCREEN_NUMBER; |
1703 | |
c5e9c988 |
1704 | MD5Init(&md5c); |
374330e2 |
1705 | MD5Update(&md5c, keystr2, hostkey.bytes); |
1706 | MD5Update(&md5c, keystr1, servkey.bytes); |
1707 | MD5Update(&md5c, pktin.body, 8); |
374330e2 |
1708 | MD5Final(session_id, &md5c); |
1709 | |
32874aea |
1710 | for (i = 0; i < 32; i++) |
374330e2 |
1711 | session_key[i] = random_byte(); |
1712 | |
1713 | len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes); |
1714 | |
dcbde236 |
1715 | rsabuf = smalloc(len); |
374330e2 |
1716 | if (!rsabuf) |
1717 | fatalbox("Out of memory"); |
1718 | |
89ee5268 |
1719 | /* |
1720 | * Verify the host key. |
1721 | */ |
1722 | { |
32874aea |
1723 | /* |
1724 | * First format the key into a string. |
1725 | */ |
1726 | int len = rsastr_len(&hostkey); |
1727 | char fingerprint[100]; |
1728 | char *keystr = smalloc(len); |
1729 | if (!keystr) |
1730 | fatalbox("Out of memory"); |
1731 | rsastr_fmt(keystr, &hostkey); |
1732 | rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey); |
1733 | verify_ssh_host_key(savedhost, savedport, "rsa", keystr, |
1734 | fingerprint); |
1735 | sfree(keystr); |
1736 | } |
1737 | |
1738 | for (i = 0; i < 32; i++) { |
374330e2 |
1739 | rsabuf[i] = session_key[i]; |
1740 | if (i < 16) |
1741 | rsabuf[i] ^= session_id[i]; |
1742 | } |
1743 | |
1744 | if (hostkey.bytes > servkey.bytes) { |
1745 | rsaencrypt(rsabuf, 32, &servkey); |
1746 | rsaencrypt(rsabuf, servkey.bytes, &hostkey); |
1747 | } else { |
1748 | rsaencrypt(rsabuf, 32, &hostkey); |
1749 | rsaencrypt(rsabuf, hostkey.bytes, &servkey); |
1750 | } |
1751 | |
c5e9c988 |
1752 | logevent("Encrypted session key"); |
1753 | |
0a3f1d48 |
1754 | switch (cfg.cipher) { |
32874aea |
1755 | case CIPHER_BLOWFISH: |
1756 | cipher_type = SSH_CIPHER_BLOWFISH; |
1757 | break; |
1758 | case CIPHER_DES: |
1759 | cipher_type = SSH_CIPHER_DES; |
1760 | break; |
1761 | case CIPHER_3DES: |
1762 | cipher_type = SSH_CIPHER_3DES; |
1763 | break; |
0a3f1d48 |
1764 | case CIPHER_AES: |
32874aea |
1765 | c_write_str("AES not supported in SSH1, falling back to 3DES\r\n"); |
1766 | cipher_type = SSH_CIPHER_3DES; |
1767 | break; |
0a3f1d48 |
1768 | } |
bea1ef5f |
1769 | if ((supported_ciphers_mask & (1 << cipher_type)) == 0) { |
32874aea |
1770 | c_write_str |
1771 | ("Selected cipher not supported, falling back to 3DES\r\n"); |
bea1ef5f |
1772 | cipher_type = SSH_CIPHER_3DES; |
a99a05c0 |
1773 | if ((supported_ciphers_mask & (1 << cipher_type)) == 0) { |
1774 | bombout(("Server violates SSH 1 protocol by " |
1775 | "not supporting 3DES encryption")); |
1776 | crReturn(0); |
1777 | } |
bea1ef5f |
1778 | } |
c5e9c988 |
1779 | switch (cipher_type) { |
32874aea |
1780 | case SSH_CIPHER_3DES: |
1781 | logevent("Using 3DES encryption"); |
1782 | break; |
1783 | case SSH_CIPHER_DES: |
1784 | logevent("Using single-DES encryption"); |
1785 | break; |
1786 | case SSH_CIPHER_BLOWFISH: |
1787 | logevent("Using Blowfish encryption"); |
1788 | break; |
c5e9c988 |
1789 | } |
bea1ef5f |
1790 | |
e5574168 |
1791 | send_packet(SSH1_CMSG_SESSION_KEY, |
32874aea |
1792 | PKT_CHAR, cipher_type, |
1793 | PKT_DATA, cookie, 8, |
1794 | PKT_CHAR, (len * 8) >> 8, PKT_CHAR, (len * 8) & 0xFF, |
1795 | PKT_DATA, rsabuf, len, |
1796 | PKT_INT, ssh1_local_protoflags, PKT_END); |
fb09bf1c |
1797 | |
c5e9c988 |
1798 | logevent("Trying to enable encryption..."); |
374330e2 |
1799 | |
dcbde236 |
1800 | sfree(rsabuf); |
374330e2 |
1801 | |
5e8358ad |
1802 | cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 : |
32874aea |
1803 | cipher_type == SSH_CIPHER_DES ? &ssh_des : &ssh_3des; |
374330e2 |
1804 | cipher->sesskey(session_key); |
1805 | |
fb09bf1c |
1806 | crWaitUntil(ispkt); |
374330e2 |
1807 | |
8d5de777 |
1808 | if (pktin.type != SSH1_SMSG_SUCCESS) { |
1809 | bombout(("Encryption not successfully enabled")); |
32874aea |
1810 | crReturn(0); |
8d5de777 |
1811 | } |
374330e2 |
1812 | |
c5e9c988 |
1813 | logevent("Successfully started encryption"); |
1814 | |
374330e2 |
1815 | fflush(stdout); |
1816 | { |
374330e2 |
1817 | static int pos = 0; |
1818 | static char c; |
67779be7 |
1819 | if ((flags & FLAG_INTERACTIVE) && !*cfg.username) { |
32874aea |
1820 | if (ssh_get_line) { |
1821 | if (!ssh_get_line("login as: ", |
1822 | username, sizeof(username), FALSE)) { |
1823 | /* |
1824 | * get_line failed to get a username. |
1825 | * Terminate. |
1826 | */ |
1827 | logevent("No username provided. Abandoning session."); |
1828 | ssh_state = SSH_STATE_CLOSED; |
1829 | crReturn(1); |
1830 | } |
1831 | } else { |
1832 | c_write_str("login as: "); |
1833 | ssh_send_ok = 1; |
1834 | while (pos >= 0) { |
1835 | crWaitUntil(!ispkt); |
1836 | while (inlen--) |
1837 | switch (c = *in++) { |
1838 | case 10: |
1839 | case 13: |
1840 | username[pos] = 0; |
1841 | pos = -1; |
1842 | break; |
1843 | case 8: |
1844 | case 127: |
1845 | if (pos > 0) { |
1846 | c_write_str("\b \b"); |
1847 | pos--; |
1848 | } |
1849 | break; |
1850 | case 21: |
1851 | case 27: |
1852 | while (pos > 0) { |
1853 | c_write_str("\b \b"); |
1854 | pos--; |
1855 | } |
1856 | break; |
1857 | case 3: |
1858 | case 4: |
1859 | random_save_seed(); |
1860 | exit(0); |
1861 | break; |
1862 | default: |
1863 | if (((c >= ' ' && c <= '~') || |
51b2fb65 |
1864 | ((unsigned char) c >= 160)) |
1865 | && pos < sizeof(username)-1) { |
32874aea |
1866 | username[pos++] = c; |
1867 | c_write(&c, 1); |
1868 | } |
1869 | break; |
1870 | } |
1871 | } |
1872 | c_write_str("\r\n"); |
1873 | username[strcspn(username, "\n\r")] = '\0'; |
1874 | } |
1875 | } else { |
374330e2 |
1876 | strncpy(username, cfg.username, 99); |
1877 | username[99] = '\0'; |
374330e2 |
1878 | } |
fb09bf1c |
1879 | |
e5574168 |
1880 | send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END); |
c5e9c988 |
1881 | { |
32874aea |
1882 | char userlog[22 + sizeof(username)]; |
c5e9c988 |
1883 | sprintf(userlog, "Sent username \"%s\"", username); |
1884 | logevent(userlog); |
32874aea |
1885 | if (flags & FLAG_INTERACTIVE && |
1886 | (!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) { |
3c8e959b |
1887 | strcat(userlog, "\r\n"); |
32874aea |
1888 | c_write_str(userlog); |
3c8e959b |
1889 | } |
c5e9c988 |
1890 | } |
374330e2 |
1891 | } |
1892 | |
fb09bf1c |
1893 | crWaitUntil(ispkt); |
374330e2 |
1894 | |
7cca0d81 |
1895 | tried_publickey = 0; |
1896 | |
e5574168 |
1897 | while (pktin.type == SSH1_SMSG_FAILURE) { |
374330e2 |
1898 | static char password[100]; |
a52f067e |
1899 | static char prompt[200]; |
374330e2 |
1900 | static int pos; |
1901 | static char c; |
32874aea |
1902 | static int pwpkt_type; |
1903 | /* |
1904 | * Show password prompt, having first obtained it via a TIS |
1905 | * or CryptoCard exchange if we're doing TIS or CryptoCard |
1906 | * authentication. |
1907 | */ |
1908 | pwpkt_type = SSH1_CMSG_AUTH_PASSWORD; |
1909 | if (agent_exists()) { |
1910 | /* |
1911 | * Attempt RSA authentication using Pageant. |
1912 | */ |
1913 | static unsigned char request[5], *response, *p; |
1914 | static int responselen; |
1915 | static int i, nkeys; |
1916 | static int authed = FALSE; |
1917 | void *r; |
1918 | |
1919 | logevent("Pageant is running. Requesting keys."); |
1920 | |
1921 | /* Request the keys held by the agent. */ |
1922 | PUT_32BIT(request, 1); |
1923 | request[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES; |
1924 | agent_query(request, 5, &r, &responselen); |
1925 | response = (unsigned char *) r; |
1926 | if (response && responselen >= 5 && |
1927 | response[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER) { |
1928 | p = response + 5; |
1929 | nkeys = GET_32BIT(p); |
1930 | p += 4; |
1931 | { |
1932 | char buf[64]; |
1933 | sprintf(buf, "Pageant has %d SSH1 keys", nkeys); |
1934 | logevent(buf); |
1935 | } |
1936 | for (i = 0; i < nkeys; i++) { |
1937 | static struct RSAKey key; |
1938 | static Bignum challenge; |
1939 | static char *commentp; |
1940 | static int commentlen; |
1941 | |
1942 | { |
1943 | char buf[64]; |
1944 | sprintf(buf, "Trying Pageant key #%d", i); |
1945 | logevent(buf); |
1946 | } |
1947 | p += 4; |
1948 | p += ssh1_read_bignum(p, &key.exponent); |
1949 | p += ssh1_read_bignum(p, &key.modulus); |
1950 | commentlen = GET_32BIT(p); |
1951 | p += 4; |
1952 | commentp = p; |
1953 | p += commentlen; |
1954 | send_packet(SSH1_CMSG_AUTH_RSA, |
1955 | PKT_BIGNUM, key.modulus, PKT_END); |
1956 | crWaitUntil(ispkt); |
1957 | if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) { |
1958 | logevent("Key refused"); |
1959 | continue; |
1960 | } |
1961 | logevent("Received RSA challenge"); |
1962 | ssh1_read_bignum(pktin.body, &challenge); |
1963 | { |
1964 | char *agentreq, *q, *ret; |
2d466ffd |
1965 | void *vret; |
32874aea |
1966 | int len, retlen; |
1967 | len = 1 + 4; /* message type, bit count */ |
1968 | len += ssh1_bignum_length(key.exponent); |
1969 | len += ssh1_bignum_length(key.modulus); |
1970 | len += ssh1_bignum_length(challenge); |
1971 | len += 16; /* session id */ |
1972 | len += 4; /* response format */ |
1973 | agentreq = smalloc(4 + len); |
1974 | PUT_32BIT(agentreq, len); |
1975 | q = agentreq + 4; |
1976 | *q++ = SSH1_AGENTC_RSA_CHALLENGE; |
1977 | PUT_32BIT(q, bignum_bitcount(key.modulus)); |
1978 | q += 4; |
1979 | q += ssh1_write_bignum(q, key.exponent); |
1980 | q += ssh1_write_bignum(q, key.modulus); |
1981 | q += ssh1_write_bignum(q, challenge); |
1982 | memcpy(q, session_id, 16); |
1983 | q += 16; |
1984 | PUT_32BIT(q, 1); /* response format */ |
2d466ffd |
1985 | agent_query(agentreq, len + 4, &vret, &retlen); |
1986 | ret = vret; |
32874aea |
1987 | sfree(agentreq); |
1988 | if (ret) { |
1989 | if (ret[4] == SSH1_AGENT_RSA_RESPONSE) { |
1990 | logevent("Sending Pageant's response"); |
1991 | send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE, |
1992 | PKT_DATA, ret + 5, 16, |
1993 | PKT_END); |
1994 | sfree(ret); |
1995 | crWaitUntil(ispkt); |
1996 | if (pktin.type == SSH1_SMSG_SUCCESS) { |
1997 | logevent |
1998 | ("Pageant's response accepted"); |
1999 | if (flags & FLAG_VERBOSE) { |
2000 | c_write_str |
2001 | ("Authenticated using RSA key \""); |
2002 | c_write(commentp, commentlen); |
2003 | c_write_str("\" from agent\r\n"); |
2004 | } |
2005 | authed = TRUE; |
2006 | } else |
2007 | logevent |
2008 | ("Pageant's response not accepted"); |
2009 | } else { |
2010 | logevent |
2011 | ("Pageant failed to answer challenge"); |
2012 | sfree(ret); |
2013 | } |
2014 | } else { |
2015 | logevent("No reply received from Pageant"); |
2016 | } |
2017 | } |
2018 | freebn(key.exponent); |
2019 | freebn(key.modulus); |
2020 | freebn(challenge); |
2021 | if (authed) |
2022 | break; |
2023 | } |
2024 | } |
2025 | if (authed) |
2026 | break; |
2027 | } |
2028 | if (*cfg.keyfile && !tried_publickey) |
2029 | pwpkt_type = SSH1_CMSG_AUTH_RSA; |
2030 | |
2031 | if (pktin.type == SSH1_SMSG_FAILURE && |
2032 | cfg.try_tis_auth && |
2033 | (supported_auths_mask & (1 << SSH1_AUTH_TIS))) { |
2034 | pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE; |
2035 | logevent("Requested TIS authentication"); |
2036 | send_packet(SSH1_CMSG_AUTH_TIS, PKT_END); |
2037 | crWaitUntil(ispkt); |
2038 | if (pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) { |
2039 | logevent("TIS authentication declined"); |
2040 | if (flags & FLAG_INTERACTIVE) |
2041 | c_write_str("TIS authentication refused.\r\n"); |
2042 | } else { |
2043 | int challengelen = ((pktin.body[0] << 24) | |
2044 | (pktin.body[1] << 16) | |
2045 | (pktin.body[2] << 8) | |
2046 | (pktin.body[3])); |
2047 | logevent("Received TIS challenge"); |
2048 | if (challengelen > sizeof(prompt) - 1) |
2049 | challengelen = sizeof(prompt) - 1; /* prevent overrun */ |
2050 | memcpy(prompt, pktin.body + 4, challengelen); |
2051 | prompt[challengelen] = '\0'; |
2052 | } |
2053 | } |
2054 | if (pktin.type == SSH1_SMSG_FAILURE && |
2055 | cfg.try_tis_auth && |
2056 | (supported_auths_mask & (1 << SSH1_AUTH_CCARD))) { |
2057 | pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE; |
2058 | logevent("Requested CryptoCard authentication"); |
2059 | send_packet(SSH1_CMSG_AUTH_CCARD, PKT_END); |
2060 | crWaitUntil(ispkt); |
2061 | if (pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) { |
2062 | logevent("CryptoCard authentication declined"); |
2063 | c_write_str("CryptoCard authentication refused.\r\n"); |
2064 | } else { |
2065 | int challengelen = ((pktin.body[0] << 24) | |
2066 | (pktin.body[1] << 16) | |
2067 | (pktin.body[2] << 8) | |
2068 | (pktin.body[3])); |
2069 | logevent("Received CryptoCard challenge"); |
2070 | if (challengelen > sizeof(prompt) - 1) |
2071 | challengelen = sizeof(prompt) - 1; /* prevent overrun */ |
2072 | memcpy(prompt, pktin.body + 4, challengelen); |
2073 | strncpy(prompt + challengelen, "\r\nResponse : ", |
2074 | sizeof(prompt) - challengelen); |
2075 | prompt[sizeof(prompt) - 1] = '\0'; |
2076 | } |
2077 | } |
2078 | if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) { |
2079 | sprintf(prompt, "%.90s@%.90s's password: ", |
2080 | username, savedhost); |
2081 | } |
2082 | if (pwpkt_type == SSH1_CMSG_AUTH_RSA) { |
2083 | char *comment = NULL; |
2084 | if (flags & FLAG_VERBOSE) |
2085 | c_write_str("Trying public key authentication.\r\n"); |
2086 | if (!rsakey_encrypted(cfg.keyfile, &comment)) { |
2087 | if (flags & FLAG_VERBOSE) |
2088 | c_write_str("No passphrase required.\r\n"); |
2089 | goto tryauth; |
2090 | } |
2091 | sprintf(prompt, "Passphrase for key \"%.100s\": ", comment); |
2092 | sfree(comment); |
2093 | } |
a52f067e |
2094 | |
fa17a66e |
2095 | if (ssh_get_line) { |
2096 | if (!ssh_get_line(prompt, password, sizeof(password), TRUE)) { |
32874aea |
2097 | /* |
2098 | * get_line failed to get a password (for example |
2099 | * because one was supplied on the command line |
2100 | * which has already failed to work). Terminate. |
2101 | */ |
2bc6a386 |
2102 | send_packet(SSH1_MSG_DISCONNECT, |
2103 | PKT_STR, "No more passwords available to try", |
2104 | PKT_END); |
2105 | connection_fatal("Unable to authenticate"); |
32874aea |
2106 | ssh_state = SSH_STATE_CLOSED; |
2107 | crReturn(1); |
2108 | } |
fb09bf1c |
2109 | } else { |
32874aea |
2110 | c_write_str(prompt); |
2111 | pos = 0; |
2112 | ssh_send_ok = 1; |
2113 | while (pos >= 0) { |
2114 | crWaitUntil(!ispkt); |
2115 | while (inlen--) |
2116 | switch (c = *in++) { |
2117 | case 10: |
2118 | case 13: |
2119 | password[pos] = 0; |
2120 | pos = -1; |
2121 | break; |
2122 | case 8: |
2123 | case 127: |
2124 | if (pos > 0) |
2125 | pos--; |
2126 | break; |
2127 | case 21: |
2128 | case 27: |
2129 | pos = 0; |
2130 | break; |
2131 | case 3: |
2132 | case 4: |
2133 | random_save_seed(); |
2134 | exit(0); |
2135 | break; |
2136 | default: |
51b2fb65 |
2137 | if (pos < sizeof(password)-1) |
32874aea |
2138 | password[pos++] = c; |
2139 | break; |
2140 | } |
2141 | } |
2142 | c_write_str("\r\n"); |
2143 | } |
2144 | |
2145 | tryauth: |
7cca0d81 |
2146 | if (pwpkt_type == SSH1_CMSG_AUTH_RSA) { |
32874aea |
2147 | /* |
2148 | * Try public key authentication with the specified |
2149 | * key file. |
2150 | */ |
2151 | static struct RSAKey pubkey; |
2152 | static Bignum challenge, response; |
2153 | static int i; |
2154 | static unsigned char buffer[32]; |
2155 | |
2156 | tried_publickey = 1; |
2157 | i = loadrsakey(cfg.keyfile, &pubkey, password); |
2158 | if (i == 0) { |
2159 | c_write_str("Couldn't load public key from "); |
2160 | c_write_str(cfg.keyfile); |
2161 | c_write_str(".\r\n"); |
2162 | continue; /* go and try password */ |
2163 | } |
2164 | if (i == -1) { |
2165 | c_write_str("Wrong passphrase.\r\n"); |
2166 | tried_publickey = 0; |
2167 | continue; /* try again */ |
2168 | } |
2169 | |
2170 | /* |
2171 | * Send a public key attempt. |
2172 | */ |
2173 | send_packet(SSH1_CMSG_AUTH_RSA, |
2174 | PKT_BIGNUM, pubkey.modulus, PKT_END); |
2175 | |
2176 | crWaitUntil(ispkt); |
2177 | if (pktin.type == SSH1_SMSG_FAILURE) { |
2178 | c_write_str("Server refused our public key.\r\n"); |
2179 | continue; /* go and try password */ |
2180 | } |
2181 | if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) { |
2182 | bombout(("Bizarre response to offer of public key")); |
2183 | crReturn(0); |
2184 | } |
2185 | ssh1_read_bignum(pktin.body, &challenge); |
2186 | response = rsadecrypt(challenge, &pubkey); |
2187 | freebn(pubkey.private_exponent); /* burn the evidence */ |
2188 | |
2189 | for (i = 0; i < 32; i++) { |
2190 | buffer[i] = bignum_byte(response, 31 - i); |
2191 | } |
2192 | |
2193 | MD5Init(&md5c); |
2194 | MD5Update(&md5c, buffer, 32); |
2195 | MD5Update(&md5c, session_id, 16); |
2196 | MD5Final(buffer, &md5c); |
2197 | |
2198 | send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE, |
2199 | PKT_DATA, buffer, 16, PKT_END); |
2200 | |
2201 | crWaitUntil(ispkt); |
2202 | if (pktin.type == SSH1_SMSG_FAILURE) { |
2203 | if (flags & FLAG_VERBOSE) |
2204 | c_write_str |
2205 | ("Failed to authenticate with our public key.\r\n"); |
2206 | continue; /* go and try password */ |
2207 | } else if (pktin.type != SSH1_SMSG_SUCCESS) { |
2208 | bombout( |
2209 | ("Bizarre response to RSA authentication response")); |
2210 | crReturn(0); |
2211 | } |
2212 | |
2213 | break; /* we're through! */ |
2214 | } else { |
2215 | if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) { |
2216 | /* |
2217 | * Defence against traffic analysis: we send a |
2218 | * whole bunch of packets containing strings of |
2219 | * different lengths. One of these strings is the |
2220 | * password, in a SSH1_CMSG_AUTH_PASSWORD packet. |
2221 | * The others are all random data in |
2222 | * SSH1_MSG_IGNORE packets. This way a passive |
2223 | * listener can't tell which is the password, and |
2224 | * hence can't deduce the password length. |
2225 | * |
2226 | * Anybody with a password length greater than 16 |
2227 | * bytes is going to have enough entropy in their |
2228 | * password that a listener won't find it _that_ |
2229 | * much help to know how long it is. So what we'll |
2230 | * do is: |
2231 | * |
2232 | * - if password length < 16, we send 15 packets |
2233 | * containing string lengths 1 through 15 |
2234 | * |
2235 | * - otherwise, we let N be the nearest multiple |
2236 | * of 8 below the password length, and send 8 |
2237 | * packets containing string lengths N through |
2238 | * N+7. This won't obscure the order of |
2239 | * magnitude of the password length, but it will |
2240 | * introduce a bit of extra uncertainty. |
2241 | * |
2242 | * A few servers (the old 1.2.18 through 1.2.22) |
2243 | * can't deal with SSH1_MSG_IGNORE. For these |
2244 | * servers, we need an alternative defence. We make |
2245 | * use of the fact that the password is interpreted |
2246 | * as a C string: so we can append a NUL, then some |
2247 | * random data. |
2248 | */ |
2249 | if (ssh_remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE) { |
2250 | char string[64]; |
2251 | char *s; |
2252 | int len; |
2253 | |
2254 | len = strlen(password); |
2255 | if (len < sizeof(string)) { |
2256 | s = string; |
2257 | strcpy(string, password); |
2258 | len++; /* cover the zero byte */ |
2259 | while (len < sizeof(string)) { |
2260 | string[len++] = (char) random_byte(); |
2261 | } |
2262 | } else { |
2263 | s = password; |
2264 | } |
2265 | send_packet(pwpkt_type, PKT_INT, len, |
2266 | PKT_DATA, s, len, PKT_END); |
2267 | } else { |
2268 | int bottom, top, pwlen, i; |
2269 | char *randomstr; |
2270 | |
2271 | pwlen = strlen(password); |
2272 | if (pwlen < 16) { |
2273 | bottom = 0; /* zero length passwords are OK! :-) */ |
2274 | top = 15; |
2275 | } else { |
2276 | bottom = pwlen & ~7; |
2277 | top = bottom + 7; |
2278 | } |
2279 | |
2280 | assert(pwlen >= bottom && pwlen <= top); |
2281 | |
2282 | randomstr = smalloc(top + 1); |
2283 | |
2284 | for (i = bottom; i <= top; i++) { |
2285 | if (i == pwlen) |
2286 | defer_packet(pwpkt_type, PKT_STR, password, |
2287 | PKT_END); |
2288 | else { |
2289 | for (j = 0; j < i; j++) { |
2290 | do { |
2291 | randomstr[j] = random_byte(); |
2292 | } while (randomstr[j] == '\0'); |
2293 | } |
2294 | randomstr[i] = '\0'; |
2295 | defer_packet(SSH1_MSG_IGNORE, |
2296 | PKT_STR, randomstr, PKT_END); |
2297 | } |
2298 | } |
2299 | ssh_pkt_defersend(); |
2300 | } |
2301 | } else { |
2302 | send_packet(pwpkt_type, PKT_STR, password, PKT_END); |
2303 | } |
2304 | } |
c5e9c988 |
2305 | logevent("Sent password"); |
374330e2 |
2306 | memset(password, 0, strlen(password)); |
fb09bf1c |
2307 | crWaitUntil(ispkt); |
e5574168 |
2308 | if (pktin.type == SSH1_SMSG_FAILURE) { |
32874aea |
2309 | if (flags & FLAG_VERBOSE) |
2310 | c_write_str("Access denied\r\n"); |
c5e9c988 |
2311 | logevent("Authentication refused"); |
e5574168 |
2312 | } else if (pktin.type == SSH1_MSG_DISCONNECT) { |
fb09bf1c |
2313 | logevent("Received disconnect request"); |
32874aea |
2314 | ssh_state = SSH_STATE_CLOSED; |
85ee8208 |
2315 | crReturn(1); |
e5574168 |
2316 | } else if (pktin.type != SSH1_SMSG_SUCCESS) { |
8d5de777 |
2317 | bombout(("Strange packet received, type %d", pktin.type)); |
32874aea |
2318 | crReturn(0); |
374330e2 |
2319 | } |
2320 | } |
2321 | |
c5e9c988 |
2322 | logevent("Authentication successful"); |
2323 | |
fb09bf1c |
2324 | crFinish(1); |
2325 | } |
2326 | |
32874aea |
2327 | void sshfwd_close(struct ssh_channel *c) |
2328 | { |
80e48603 |
2329 | if (c && !c->closes) { |
32874aea |
2330 | if (ssh_version == 1) { |
2331 | send_packet(SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid, |
2332 | PKT_END); |
2333 | } else { |
2334 | ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE); |
2335 | ssh2_pkt_adduint32(c->remoteid); |
2336 | ssh2_pkt_send(); |
2337 | } |
2338 | c->closes = 1; |
2339 | if (c->type == CHAN_X11) { |
2340 | c->u.x11.s = NULL; |
d74d141c |
2341 | logevent("Forwarded X11 connection terminated"); |
2342 | } else if (c->type == CHAN_SOCKDATA) { |
2343 | c->u.pfd.s = NULL; |
2344 | logevent("Forwarded port closed"); |
32874aea |
2345 | } |
2346 | } |
2347 | } |
2348 | |
2349 | void sshfwd_write(struct ssh_channel *c, char *buf, int len) |
2350 | { |
783415f8 |
2351 | if (ssh_version == 1) { |
32874aea |
2352 | send_packet(SSH1_MSG_CHANNEL_DATA, |
2353 | PKT_INT, c->remoteid, |
2354 | PKT_INT, len, PKT_DATA, buf, len, PKT_END); |
783415f8 |
2355 | } else { |
32874aea |
2356 | ssh2_add_channel_data(c, buf, len); |
2357 | ssh2_try_send(c); |
783415f8 |
2358 | } |
9c964e85 |
2359 | } |
2360 | |
32874aea |
2361 | static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) |
2362 | { |
fb09bf1c |
2363 | crBegin; |
2364 | |
2365 | random_init(); |
2366 | |
e5574168 |
2367 | while (!do_ssh1_login(in, inlen, ispkt)) { |
fb09bf1c |
2368 | crReturnV; |
85ee8208 |
2369 | } |
2370 | if (ssh_state == SSH_STATE_CLOSED) |
32874aea |
2371 | crReturnV; |
fb09bf1c |
2372 | |
979310f1 |
2373 | if (cfg.agentfwd && agent_exists()) { |
32874aea |
2374 | logevent("Requesting agent forwarding"); |
2375 | send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END); |
2376 | do { |
2377 | crReturnV; |
2378 | } while (!ispkt); |
2379 | if (pktin.type != SSH1_SMSG_SUCCESS |
2380 | && pktin.type != SSH1_SMSG_FAILURE) { |
2381 | bombout(("Protocol confusion")); |
2382 | crReturnV; |
2383 | } else if (pktin.type == SSH1_SMSG_FAILURE) { |
2384 | logevent("Agent forwarding refused"); |
2385 | } else { |
2386 | logevent("Agent forwarding enabled"); |
db7d555c |
2387 | ssh_agentfwd_enabled = TRUE; |
2388 | } |
dacbd0e8 |
2389 | } |
2390 | |
9c964e85 |
2391 | if (cfg.x11_forward) { |
32874aea |
2392 | char proto[20], data[64]; |
2393 | logevent("Requesting X11 forwarding"); |
2394 | x11_invent_auth(proto, sizeof(proto), data, sizeof(data)); |
2395 | if (ssh1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) { |
2396 | send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING, |
2397 | PKT_STR, proto, PKT_STR, data, |
2398 | PKT_INT, 0, PKT_END); |
2399 | } else { |
2400 | send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING, |
2401 | PKT_STR, proto, PKT_STR, data, PKT_END); |
2402 | } |
2403 | do { |
2404 | crReturnV; |
2405 | } while (!ispkt); |
2406 | if (pktin.type != SSH1_SMSG_SUCCESS |
2407 | && pktin.type != SSH1_SMSG_FAILURE) { |
2408 | bombout(("Protocol confusion")); |
2409 | crReturnV; |
2410 | } else if (pktin.type == SSH1_SMSG_FAILURE) { |
2411 | logevent("X11 forwarding refused"); |
2412 | } else { |
2413 | logevent("X11 forwarding enabled"); |
9c964e85 |
2414 | ssh_X11_fwd_enabled = TRUE; |
2415 | } |
2416 | } |
2417 | |
d74d141c |
2418 | { |
2419 | char type, *e; |
2420 | int n; |
2421 | int sport,dport; |
2422 | char sports[256], dports[256], host[256]; |
2423 | char buf[1024]; |
2424 | |
bc240b21 |
2425 | ssh_rportfwds = newtree234(ssh_rportcmp_ssh1); |
d74d141c |
2426 | /* Add port forwardings. */ |
2427 | e = cfg.portfwd; |
2428 | while (*e) { |
2429 | type = *e++; |
2430 | n = 0; |
2431 | while (*e && *e != '\t') |
2432 | sports[n++] = *e++; |
2433 | sports[n] = 0; |
2434 | if (*e == '\t') |
2435 | e++; |
2436 | n = 0; |
2437 | while (*e && *e != ':') |
2438 | host[n++] = *e++; |
2439 | host[n] = 0; |
2440 | if (*e == ':') |
2441 | e++; |
2442 | n = 0; |
2443 | while (*e) |
2444 | dports[n++] = *e++; |
2445 | dports[n] = 0; |
2446 | e++; |
2447 | dport = atoi(dports); |
2448 | sport = atoi(sports); |
2449 | if (sport && dport) { |
2450 | if (type == 'L') { |
2451 | pfd_addforward(host, dport, sport); |
2452 | sprintf(buf, "Local port %d forwarding to %s:%d", |
2453 | sport, host, dport); |
2454 | logevent(buf); |
2455 | } else { |
2456 | struct ssh_rportfwd *pf; |
2457 | pf = smalloc(sizeof(*pf)); |
bc240b21 |
2458 | strcpy(pf->dhost, host); |
2459 | pf->dport = dport; |
d74d141c |
2460 | if (add234(ssh_rportfwds, pf) != pf) { |
2461 | sprintf(buf, |
95bc8819 |
2462 | "Duplicate remote port forwarding to %s:%d", |
d74d141c |
2463 | host, dport); |
2464 | logevent(buf); |
bc240b21 |
2465 | sfree(pf); |
d74d141c |
2466 | } else { |
2467 | sprintf(buf, "Requesting remote port %d forward to %s:%d", |
2468 | sport, host, dport); |
2469 | logevent(buf); |
2470 | send_packet(SSH1_CMSG_PORT_FORWARD_REQUEST, |
2471 | PKT_INT, sport, |
2472 | PKT_STR, host, |
2473 | PKT_INT, dport, |
2474 | PKT_END); |
2475 | } |
2476 | } |
2477 | } |
2478 | } |
2479 | } |
2480 | |
fef97f43 |
2481 | if (!cfg.nopty) { |
e5574168 |
2482 | send_packet(SSH1_CMSG_REQUEST_PTY, |
32874aea |
2483 | PKT_STR, cfg.termtype, |
2484 | PKT_INT, rows, PKT_INT, cols, |
2485 | PKT_INT, 0, PKT_INT, 0, PKT_CHAR, 0, PKT_END); |
2486 | ssh_state = SSH_STATE_INTERMED; |
2487 | do { |
2488 | crReturnV; |
2489 | } while (!ispkt); |
2490 | if (pktin.type != SSH1_SMSG_SUCCESS |
2491 | && pktin.type != SSH1_SMSG_FAILURE) { |
2492 | bombout(("Protocol confusion")); |
2493 | crReturnV; |
2494 | } else if (pktin.type == SSH1_SMSG_FAILURE) { |
2495 | c_write_str("Server refused to allocate pty\r\n"); |
2496 | ssh_editing = ssh_echoing = 1; |
2497 | } |
c5e9c988 |
2498 | logevent("Allocated pty"); |
0965bee0 |
2499 | } else { |
32874aea |
2500 | ssh_editing = ssh_echoing = 1; |
374330e2 |
2501 | } |
2502 | |
4ba9b64b |
2503 | if (cfg.compression) { |
32874aea |
2504 | send_packet(SSH1_CMSG_REQUEST_COMPRESSION, PKT_INT, 6, PKT_END); |
2505 | do { |
2506 | crReturnV; |
2507 | } while (!ispkt); |
2508 | if (pktin.type != SSH1_SMSG_SUCCESS |
2509 | && pktin.type != SSH1_SMSG_FAILURE) { |
2510 | bombout(("Protocol confusion")); |
2511 | crReturnV; |
2512 | } else if (pktin.type == SSH1_SMSG_FAILURE) { |
2513 | c_write_str("Server refused to compress\r\n"); |
2514 | } |
4ba9b64b |
2515 | logevent("Started compression"); |
2516 | ssh1_compressing = TRUE; |
2517 | zlib_compress_init(); |
2518 | zlib_decompress_init(); |
2519 | } |
2520 | |
96621a84 |
2521 | if (*cfg.remote_cmd_ptr) |
32874aea |
2522 | send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cfg.remote_cmd_ptr, |
2523 | PKT_END); |
6abbf9e3 |
2524 | else |
32874aea |
2525 | send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END); |
c5e9c988 |
2526 | logevent("Started session"); |
374330e2 |
2527 | |
2528 | ssh_state = SSH_STATE_SESSION; |
2529 | if (size_needed) |
2530 | ssh_size(); |
3687d221 |
2531 | if (eof_needed) |
32874aea |
2532 | ssh_special(TS_EOF); |
374330e2 |
2533 | |
32874aea |
2534 | ldisc_send(NULL, 0); /* cause ldisc to notice changes */ |
8ccc75b0 |
2535 | ssh_send_ok = 1; |
dacbd0e8 |
2536 | ssh_channels = newtree234(ssh_channelcmp); |
374330e2 |
2537 | while (1) { |
2538 | crReturnV; |
2539 | if (ispkt) { |
e5574168 |
2540 | if (pktin.type == SSH1_SMSG_STDOUT_DATA || |
32874aea |
2541 | pktin.type == SSH1_SMSG_STDERR_DATA) { |
fb09bf1c |
2542 | long len = GET_32BIT(pktin.body); |
fe50e814 |
2543 | from_backend(pktin.type == SSH1_SMSG_STDERR_DATA, |
32874aea |
2544 | pktin.body + 4, len); |
e5574168 |
2545 | } else if (pktin.type == SSH1_MSG_DISCONNECT) { |
32874aea |
2546 | ssh_state = SSH_STATE_CLOSED; |
c5e9c988 |
2547 | logevent("Received disconnect request"); |
32874aea |
2548 | crReturnV; |
2549 | } else if (pktin.type == SSH1_SMSG_X11_OPEN) { |
2550 | /* Remote side is trying to open a channel to talk to our |
2551 | * X-Server. Give them back a local channel number. */ |
2552 | struct ssh_channel *c; |
9c964e85 |
2553 | |
2554 | logevent("Received X11 connect request"); |
2555 | /* Refuse if X11 forwarding is disabled. */ |
2556 | if (!ssh_X11_fwd_enabled) { |
2557 | send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE, |
32874aea |
2558 | PKT_INT, GET_32BIT(pktin.body), PKT_END); |
9c964e85 |
2559 | logevent("Rejected X11 connect request"); |
2560 | } else { |
9c964e85 |
2561 | c = smalloc(sizeof(struct ssh_channel)); |
2562 | |
32874aea |
2563 | if (x11_init(&c->u.x11.s, cfg.x11_display, c) != NULL) { |
2564 | logevent("opening X11 forward connection failed"); |
2565 | sfree(c); |
2566 | send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE, |
2567 | PKT_INT, GET_32BIT(pktin.body), |
2568 | PKT_END); |
9c964e85 |
2569 | } else { |
32874aea |
2570 | logevent |
2571 | ("opening X11 forward connection succeeded"); |
2572 | c->remoteid = GET_32BIT(pktin.body); |
2573 | c->localid = alloc_channel_id(); |
2574 | c->closes = 0; |
2575 | c->type = CHAN_X11; /* identify channel type */ |
2576 | add234(ssh_channels, c); |
2577 | send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION, |
2578 | PKT_INT, c->remoteid, PKT_INT, |
2579 | c->localid, PKT_END); |
2580 | logevent("Opened X11 forward channel"); |
9c964e85 |
2581 | } |
2582 | } |
32874aea |
2583 | } else if (pktin.type == SSH1_SMSG_AGENT_OPEN) { |
2584 | /* Remote side is trying to open a channel to talk to our |
2585 | * agent. Give them back a local channel number. */ |
2586 | struct ssh_channel *c; |
db7d555c |
2587 | |
2588 | /* Refuse if agent forwarding is disabled. */ |
2589 | if (!ssh_agentfwd_enabled) { |
2590 | send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE, |
32874aea |
2591 | PKT_INT, GET_32BIT(pktin.body), PKT_END); |
db7d555c |
2592 | } else { |
dcbde236 |
2593 | c = smalloc(sizeof(struct ssh_channel)); |
db7d555c |
2594 | c->remoteid = GET_32BIT(pktin.body); |
d2371c81 |
2595 | c->localid = alloc_channel_id(); |
db7d555c |
2596 | c->closes = 0; |
32874aea |
2597 | c->type = CHAN_AGENT; /* identify channel type */ |
db7d555c |
2598 | c->u.a.lensofar = 0; |
2599 | add234(ssh_channels, c); |
2600 | send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION, |
2601 | PKT_INT, c->remoteid, PKT_INT, c->localid, |
2602 | PKT_END); |
2603 | } |
d74d141c |
2604 | } else if (pktin.type == SSH1_MSG_PORT_OPEN) { |
2605 | /* Remote side is trying to open a channel to talk to a |
2606 | * forwarded port. Give them back a local channel number. */ |
2607 | struct ssh_channel *c; |
2608 | struct ssh_rportfwd pf; |
2609 | int hostsize, port; |
2610 | char host[256], buf[1024]; |
2611 | char *p, *h, *e; |
2612 | c = smalloc(sizeof(struct ssh_channel)); |
2613 | |
2614 | hostsize = GET_32BIT(pktin.body+4); |
2615 | for(h = host, p = pktin.body+8; hostsize != 0; hostsize--) { |
2616 | if (h+1 < host+sizeof(host)) |
2617 | *h++ = *p; |
95bc8819 |
2618 | p++; |
d74d141c |
2619 | } |
2620 | *h = 0; |
2621 | port = GET_32BIT(p); |
2622 | |
bc240b21 |
2623 | strcpy(pf.dhost, host); |
2624 | pf.dport = port; |
d74d141c |
2625 | |
2626 | if (find234(ssh_rportfwds, &pf, NULL) == NULL) { |
2627 | sprintf(buf, "Rejected remote port open request for %s:%d", |
2628 | host, port); |
2629 | logevent(buf); |
2630 | send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE, |
2631 | PKT_INT, GET_32BIT(pktin.body), PKT_END); |
2632 | } else { |
2633 | sprintf(buf, "Received remote port open request for %s:%d", |
2634 | host, port); |
2635 | logevent(buf); |
2636 | e = pfd_newconnect(&c->u.pfd.s, host, port, c); |
2637 | if (e != NULL) { |
2638 | char buf[256]; |
2639 | sprintf(buf, "Port open failed: %s", e); |
2640 | logevent(buf); |
2641 | sfree(c); |
2642 | send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE, |
2643 | PKT_INT, GET_32BIT(pktin.body), |
2644 | PKT_END); |
2645 | } else { |
2646 | c->remoteid = GET_32BIT(pktin.body); |
2647 | c->localid = alloc_channel_id(); |
2648 | c->closes = 0; |
2649 | c->type = CHAN_SOCKDATA; /* identify channel type */ |
2650 | add234(ssh_channels, c); |
2651 | send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION, |
2652 | PKT_INT, c->remoteid, PKT_INT, |
2653 | c->localid, PKT_END); |
2654 | logevent("Forwarded port opened successfully"); |
2655 | } |
2656 | } |
2657 | |
2658 | } else if (pktin.type == SSH1_MSG_CHANNEL_OPEN_CONFIRMATION) { |
bc240b21 |
2659 | unsigned int remoteid = GET_32BIT(pktin.body); |
2660 | unsigned int localid = GET_32BIT(pktin.body+4); |
2661 | struct ssh_channel *c; |
2662 | |
2663 | c = find234(ssh_channels, &remoteid, ssh_channelfind); |
2664 | if (c && c->type == CHAN_SOCKDATA_DORMANT) { |
2665 | c->remoteid = localid; |
2666 | c->type = CHAN_SOCKDATA; |
2667 | pfd_confirm(c->u.pfd.s); |
2668 | } |
d74d141c |
2669 | |
db7d555c |
2670 | } else if (pktin.type == SSH1_MSG_CHANNEL_CLOSE || |
2671 | pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) { |
32874aea |
2672 | /* Remote side closes a channel. */ |
2673 | unsigned i = GET_32BIT(pktin.body); |
2674 | struct ssh_channel *c; |
2675 | c = find234(ssh_channels, &i, ssh_channelfind); |
2676 | if (c) { |
2677 | int closetype; |
2678 | closetype = |
2679 | (pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2); |
2680 | if (!(c->closes & closetype)) |
2681 | send_packet(pktin.type, PKT_INT, c->remoteid, |
2682 | PKT_END); |
783415f8 |
2683 | if ((c->closes == 0) && (c->type == CHAN_X11)) { |
d74d141c |
2684 | logevent("Forwarded X11 connection terminated"); |
9c964e85 |
2685 | assert(c->u.x11.s != NULL); |
2686 | x11_close(c->u.x11.s); |
2687 | c->u.x11.s = NULL; |
2688 | } |
d74d141c |
2689 | if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) { |
2690 | logevent("Forwarded port closed"); |
2691 | assert(c->u.pfd.s != NULL); |
2692 | pfd_close(c->u.pfd.s); |
2693 | c->u.pfd.s = NULL; |
2694 | } |
32874aea |
2695 | c->closes |= closetype; |
2696 | if (c->closes == 3) { |
2697 | del234(ssh_channels, c); |
2698 | sfree(c); |
2699 | } |
2700 | } |
2701 | } else if (pktin.type == SSH1_MSG_CHANNEL_DATA) { |
2702 | /* Data sent down one of our channels. */ |
2703 | int i = GET_32BIT(pktin.body); |
2704 | int len = GET_32BIT(pktin.body + 4); |
2705 | unsigned char *p = pktin.body + 8; |
2706 | struct ssh_channel *c; |
2707 | c = find234(ssh_channels, &i, ssh_channelfind); |
2708 | if (c) { |
2709 | switch (c->type) { |
2710 | case CHAN_X11: |
9c964e85 |
2711 | x11_send(c->u.x11.s, p, len); |
2712 | break; |
d74d141c |
2713 | case CHAN_SOCKDATA: |
bc240b21 |
2714 | pfd_send(c->u.pfd.s, p, len); |
2715 | break; |
32874aea |
2716 | case CHAN_AGENT: |
2717 | /* Data for an agent message. Buffer it. */ |
2718 | while (len > 0) { |
2719 | if (c->u.a.lensofar < 4) { |
2720 | int l = min(4 - c->u.a.lensofar, len); |
2721 | memcpy(c->u.a.msglen + c->u.a.lensofar, p, |
2722 | l); |
2723 | p += l; |
2724 | len -= l; |
2725 | c->u.a.lensofar += l; |
2726 | } |
2727 | if (c->u.a.lensofar == 4) { |
2728 | c->u.a.totallen = |
2729 | 4 + GET_32BIT(c->u.a.msglen); |
2730 | c->u.a.message = smalloc(c->u.a.totallen); |
2731 | memcpy(c->u.a.message, c->u.a.msglen, 4); |
2732 | } |
2733 | if (c->u.a.lensofar >= 4 && len > 0) { |
2734 | int l = |
2735 | min(c->u.a.totallen - c->u.a.lensofar, |
2736 | len); |
2737 | memcpy(c->u.a.message + c->u.a.lensofar, p, |
2738 | l); |
2739 | p += l; |
2740 | len -= l; |
2741 | c->u.a.lensofar += l; |
2742 | } |
2743 | if (c->u.a.lensofar == c->u.a.totallen) { |
2744 | void *reply, *sentreply; |
2745 | int replylen; |
2746 | agent_query(c->u.a.message, |
2747 | c->u.a.totallen, &reply, |
2748 | &replylen); |
2749 | if (reply) |
2750 | sentreply = reply; |
2751 | else { |
2752 | /* Fake SSH_AGENT_FAILURE. */ |
2753 | sentreply = "\0\0\0\1\5"; |
2754 | replylen = 5; |
2755 | } |
2756 | send_packet(SSH1_MSG_CHANNEL_DATA, |
2757 | PKT_INT, c->remoteid, |
2758 | PKT_INT, replylen, |
2759 | PKT_DATA, sentreply, replylen, |
2760 | PKT_END); |
2761 | if (reply) |
2762 | sfree(reply); |
2763 | sfree(c->u.a.message); |
2764 | c->u.a.lensofar = 0; |
2765 | } |
2766 | } |
2767 | break; |
2768 | } |
2769 | } |
e5574168 |
2770 | } else if (pktin.type == SSH1_SMSG_SUCCESS) { |
972a41c8 |
2771 | /* may be from EXEC_SHELL on some servers */ |
e5574168 |
2772 | } else if (pktin.type == SSH1_SMSG_FAILURE) { |
972a41c8 |
2773 | /* may be from EXEC_SHELL on some servers |
374330e2 |
2774 | * if no pty is available or in other odd cases. Ignore */ |
e5574168 |
2775 | } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) { |
2776 | send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END); |
374330e2 |
2777 | } else { |
8d5de777 |
2778 | bombout(("Strange packet received: type %d", pktin.type)); |
32874aea |
2779 | crReturnV; |
374330e2 |
2780 | } |
2781 | } else { |
8df7a775 |
2782 | while (inlen > 0) { |
2783 | int len = min(inlen, 512); |
2784 | send_packet(SSH1_CMSG_STDIN_DATA, |
2785 | PKT_INT, len, PKT_DATA, in, len, PKT_END); |
2786 | in += len; |
2787 | inlen -= len; |
2788 | } |
374330e2 |
2789 | } |
2790 | } |
2791 | |
2792 | crFinishV; |
2793 | } |
2794 | |
2795 | /* |
e5574168 |
2796 | * Utility routine for decoding comma-separated strings in KEXINIT. |
2797 | */ |
32874aea |
2798 | static int in_commasep_string(char *needle, char *haystack, int haylen) |
2799 | { |
e5574168 |
2800 | int needlen = strlen(needle); |
2801 | while (1) { |
32874aea |
2802 | /* |
2803 | * Is it at the start of the string? |
2804 | */ |
2805 | if (haylen >= needlen && /* haystack is long enough */ |
2806 | !memcmp(needle, haystack, needlen) && /* initial match */ |
2807 | (haylen == needlen || haystack[needlen] == ',') |
2808 | /* either , or EOS follows */ |
2809 | ) |
2810 | return 1; |
2811 | /* |
2812 | * If not, search for the next comma and resume after that. |
2813 | * If no comma found, terminate. |
2814 | */ |
2815 | while (haylen > 0 && *haystack != ',') |
2816 | haylen--, haystack++; |
2817 | if (haylen == 0) |
2818 | return 0; |
2819 | haylen--, haystack++; /* skip over comma itself */ |
e5574168 |
2820 | } |
2821 | } |
2822 | |
2823 | /* |
d39f364a |
2824 | * SSH2 key creation method. |
2825 | */ |
32874aea |
2826 | static void ssh2_mkkey(Bignum K, char *H, char *sessid, char chr, |
2827 | char *keyspace) |
2828 | { |
d39f364a |
2829 | SHA_State s; |
2830 | /* First 20 bytes. */ |
2831 | SHA_Init(&s); |
2832 | sha_mpint(&s, K); |
2833 | SHA_Bytes(&s, H, 20); |
2834 | SHA_Bytes(&s, &chr, 1); |
5e0d7cb8 |
2835 | SHA_Bytes(&s, sessid, 20); |
d39f364a |
2836 | SHA_Final(&s, keyspace); |
2837 | /* Next 20 bytes. */ |
2838 | SHA_Init(&s); |
2839 | sha_mpint(&s, K); |
2840 | SHA_Bytes(&s, H, 20); |
2841 | SHA_Bytes(&s, keyspace, 20); |
32874aea |
2842 | SHA_Final(&s, keyspace + 20); |
d39f364a |
2843 | } |
2844 | |
2845 | /* |
7cca0d81 |
2846 | * Handle the SSH2 transport layer. |
e5574168 |
2847 | */ |
7cca0d81 |
2848 | static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt) |
e5574168 |
2849 | { |
7bd5a860 |
2850 | static int i, j, len, nbits, pbits; |
e5574168 |
2851 | static char *str; |
a92dd380 |
2852 | static Bignum p, g, e, f, K; |
2853 | static int kex_init_value, kex_reply_value; |
7591b9ff |
2854 | static const struct ssh_mac **maclist; |
8b2715b2 |
2855 | static int nmacs; |
0a3f1d48 |
2856 | static const struct ssh2_cipher *cscipher_tobe = NULL; |
2857 | static const struct ssh2_cipher *sccipher_tobe = NULL; |
57476f6b |
2858 | static const struct ssh_mac *csmac_tobe = NULL; |
2859 | static const struct ssh_mac *scmac_tobe = NULL; |
2860 | static const struct ssh_compress *cscomp_tobe = NULL; |
2861 | static const struct ssh_compress *sccomp_tobe = NULL; |
d5859615 |
2862 | static char *hostkeydata, *sigdata, *keystr, *fingerprint; |
e5574168 |
2863 | static int hostkeylen, siglen; |
e055a386 |
2864 | static void *hkey; /* actual host key */ |
e5574168 |
2865 | static unsigned char exchange_hash[20]; |
d39f364a |
2866 | static unsigned char keyspace[40]; |
0a3f1d48 |
2867 | static const struct ssh2_ciphers *preferred_cipher; |
4ba9b64b |
2868 | static const struct ssh_compress *preferred_comp; |
0db56f73 |
2869 | static int first_kex; |
e5574168 |
2870 | |
2871 | crBegin; |
7cca0d81 |
2872 | random_init(); |
0db56f73 |
2873 | first_kex = 1; |
e5574168 |
2874 | |
5e8358ad |
2875 | /* |
4ba9b64b |
2876 | * Set up the preferred cipher and compression. |
5e8358ad |
2877 | */ |
2878 | if (cfg.cipher == CIPHER_BLOWFISH) { |
32874aea |
2879 | preferred_cipher = &ssh2_blowfish; |
5e8358ad |
2880 | } else if (cfg.cipher == CIPHER_DES) { |
32874aea |
2881 | logevent("Single DES not supported in SSH2; using 3DES"); |
2882 | preferred_cipher = &ssh2_3des; |
5e8358ad |
2883 | } else if (cfg.cipher == CIPHER_3DES) { |
32874aea |
2884 | preferred_cipher = &ssh2_3des; |
0a3f1d48 |
2885 | } else if (cfg.cipher == CIPHER_AES) { |
32874aea |
2886 | preferred_cipher = &ssh2_aes; |
5e8358ad |
2887 | } else { |
32874aea |
2888 | /* Shouldn't happen, but we do want to initialise to _something_. */ |
2889 | preferred_cipher = &ssh2_3des; |
5e8358ad |
2890 | } |
4ba9b64b |
2891 | if (cfg.compression) |
2892 | preferred_comp = &ssh_zlib; |
2893 | else |
2894 | preferred_comp = &ssh_comp_none; |
5e8358ad |
2895 | |
7591b9ff |
2896 | /* |
2897 | * Be prepared to work around the buggy MAC problem. |
2898 | */ |
7d503c31 |
2899 | if (cfg.buggymac || (ssh_remote_bugs & BUG_SSH2_HMAC)) |
32874aea |
2900 | maclist = buggymacs, nmacs = lenof(buggymacs); |
7591b9ff |
2901 | else |
32874aea |
2902 | maclist = macs, nmacs = lenof(macs); |
7591b9ff |
2903 | |
32874aea |
2904 | begin_key_exchange: |
e5574168 |
2905 | /* |
2906 | * Construct and send our key exchange packet. |
2907 | */ |
2908 | ssh2_pkt_init(SSH2_MSG_KEXINIT); |
2909 | for (i = 0; i < 16; i++) |
32874aea |
2910 | ssh2_pkt_addbyte((unsigned char) random_byte()); |
e5574168 |
2911 | /* List key exchange algorithms. */ |
2912 | ssh2_pkt_addstring_start(); |
2913 | for (i = 0; i < lenof(kex_algs); i++) { |
32874aea |
2914 | ssh2_pkt_addstring_str(kex_algs[i]->name); |
2915 | if (i < lenof(kex_algs) - 1) |
2916 | ssh2_pkt_addstring_str(","); |
e5574168 |
2917 | } |
2918 | /* List server host key algorithms. */ |
2919 | ssh2_pkt_addstring_start(); |
2920 | for (i = 0; i < lenof(hostkey_algs); i++) { |
32874aea |
2921 | ssh2_pkt_addstring_str(hostkey_algs[i]->name); |
2922 | if (i < lenof(hostkey_algs) - 1) |
2923 | ssh2_pkt_addstring_str(","); |
e5574168 |
2924 | } |
2925 | /* List client->server encryption algorithms. */ |
2926 | ssh2_pkt_addstring_start(); |
32874aea |
2927 | for (i = 0; i < lenof(ciphers) + 1; i++) { |
2928 | const struct ssh2_ciphers *c = |
2929 | i == 0 ? preferred_cipher : ciphers[i - 1]; |
2930 | for (j = 0; j < c->nciphers; j++) { |
2931 | ssh2_pkt_addstring_str(c->list[j]->name); |
2932 | if (i < lenof(ciphers) || j < c->nciphers - 1) |
2933 | ssh2_pkt_addstring_str(","); |
2934 | } |
e5574168 |
2935 | } |
2936 | /* List server->client encryption algorithms. */ |
2937 | ssh2_pkt_addstring_start(); |
32874aea |
2938 | for (i = 0; i < lenof(ciphers) + 1; i++) { |
2939 | const struct ssh2_ciphers *c = |
2940 | i == 0 ? preferred_cipher : ciphers[i - 1]; |
2941 | for (j = 0; j < c->nciphers; j++) { |
2942 | ssh2_pkt_addstring_str(c->list[j]->name); |
2943 | if (i < lenof(ciphers) || j < c->nciphers - 1) |
2944 | ssh2_pkt_addstring_str(","); |
2945 | } |
e5574168 |
2946 | } |
2947 | /* List client->server MAC algorithms. */ |
2948 | ssh2_pkt_addstring_start(); |
8b2715b2 |
2949 | for (i = 0; i < nmacs; i++) { |
32874aea |
2950 | ssh2_pkt_addstring_str(maclist[i]->name); |
2951 | if (i < nmacs - 1) |
2952 | ssh2_pkt_addstring_str(","); |
e5574168 |
2953 | } |
2954 | /* List server->client MAC algorithms. */ |
2955 | ssh2_pkt_addstring_start(); |
8b2715b2 |
2956 | for (i = 0; i < nmacs; i++) { |
32874aea |
2957 | ssh2_pkt_addstring_str(maclist[i]->name); |
2958 | if (i < nmacs - 1) |
2959 | ssh2_pkt_addstring_str(","); |
e5574168 |
2960 | } |
2961 | /* List client->server compression algorithms. */ |
2962 | ssh2_pkt_addstring_start(); |
32874aea |
2963 | for (i = 0; i < lenof(compressions) + 1; i++) { |
2964 | const struct ssh_compress *c = |
2965 | i == 0 ? preferred_comp : compressions[i - 1]; |
2966 | ssh2_pkt_addstring_str(c->name); |
2967 | if (i < lenof(compressions)) |
2968 | ssh2_pkt_addstring_str(","); |
e5574168 |
2969 | } |
2970 | /* List server->client compression algorithms. */ |
2971 | ssh2_pkt_addstring_start(); |
32874aea |
2972 | for (i = 0; i < lenof(compressions) + 1; i++) { |
2973 | const struct ssh_compress *c = |
2974 | i == 0 ? preferred_comp : compressions[i - 1]; |
2975 | ssh2_pkt_addstring_str(c->name); |
2976 | if (i < lenof(compressions)) |
2977 | ssh2_pkt_addstring_str(","); |
e5574168 |
2978 | } |
2979 | /* List client->server languages. Empty list. */ |
2980 | ssh2_pkt_addstring_start(); |
2981 | /* List server->client languages. Empty list. */ |
2982 | ssh2_pkt_addstring_start(); |
2983 | /* First KEX packet does _not_ follow, because we're not that brave. */ |
2984 | ssh2_pkt_addbool(FALSE); |
2985 | /* Reserved. */ |
2986 | ssh2_pkt_adduint32(0); |
0db56f73 |
2987 | |
2988 | exhash = exhashbase; |
32874aea |
2989 | sha_string(&exhash, pktout.data + 5, pktout.length - 5); |
0db56f73 |
2990 | |
e5574168 |
2991 | ssh2_pkt_send(); |
2992 | |
32874aea |
2993 | if (!ispkt) |
2994 | crWaitUntil(ispkt); |
2995 | sha_string(&exhash, pktin.data + 5, pktin.length - 5); |
e5574168 |
2996 | |
2997 | /* |
2998 | * Now examine the other side's KEXINIT to see what we're up |
2999 | * to. |
3000 | */ |
7cca0d81 |
3001 | if (pktin.type != SSH2_MSG_KEXINIT) { |
32874aea |
3002 | bombout(("expected key exchange packet from server")); |
3003 | crReturn(0); |
7cca0d81 |
3004 | } |
32874aea |
3005 | kex = NULL; |
3006 | hostkey = NULL; |
3007 | cscipher_tobe = NULL; |
3008 | sccipher_tobe = NULL; |
3009 | csmac_tobe = NULL; |
3010 | scmac_tobe = NULL; |
3011 | cscomp_tobe = NULL; |
3012 | sccomp_tobe = NULL; |
3013 | pktin.savedpos += 16; /* skip garbage cookie */ |
e5574168 |
3014 | ssh2_pkt_getstring(&str, &len); /* key exchange algorithms */ |
3015 | for (i = 0; i < lenof(kex_algs); i++) { |
32874aea |
3016 | if (in_commasep_string(kex_algs[i]->name, str, len)) { |
3017 | kex = kex_algs[i]; |
3018 | break; |
3019 | } |
e5574168 |
3020 | } |
3021 | ssh2_pkt_getstring(&str, &len); /* host key algorithms */ |
3022 | for (i = 0; i < lenof(hostkey_algs); i++) { |
32874aea |
3023 | if (in_commasep_string(hostkey_algs[i]->name, str, len)) { |
3024 | hostkey = hostkey_algs[i]; |
3025 | break; |
3026 | } |
e5574168 |
3027 | } |
3028 | ssh2_pkt_getstring(&str, &len); /* client->server cipher */ |
32874aea |
3029 | for (i = 0; i < lenof(ciphers) + 1; i++) { |
3030 | const struct ssh2_ciphers *c = |
3031 | i == 0 ? preferred_cipher : ciphers[i - 1]; |
3032 | for (j = 0; j < c->nciphers; j++) { |
3033 | if (in_commasep_string(c->list[j]->name, str, len)) { |
3034 | cscipher_tobe = c->list[j]; |
3035 | break; |
3036 | } |
3037 | } |
3038 | if (cscipher_tobe) |
3039 | break; |
e5574168 |
3040 | } |
3041 | ssh2_pkt_getstring(&str, &len); /* server->client cipher */ |
32874aea |
3042 | for (i = 0; i < lenof(ciphers) + 1; i++) { |
3043 | const struct ssh2_ciphers *c = |
3044 | i == 0 ? preferred_cipher : ciphers[i - 1]; |
3045 | for (j = 0; j < c->nciphers; j++) { |
3046 | if (in_commasep_string(c->list[j]->name, str, len)) { |
3047 | sccipher_tobe = c->list[j]; |
3048 | break; |
3049 | } |
3050 | } |
3051 | if (sccipher_tobe) |
3052 | break; |
e5574168 |
3053 | } |
3054 | ssh2_pkt_getstring(&str, &len); /* client->server mac */ |
8b2715b2 |
3055 | for (i = 0; i < nmacs; i++) { |
32874aea |
3056 | if (in_commasep_string(maclist[i]->name, str, len)) { |
3057 | csmac_tobe = maclist[i]; |
3058 | break; |
3059 | } |
e5574168 |
3060 | } |
3061 | ssh2_pkt_getstring(&str, &len); /* server->client mac */ |
8b2715b2 |
3062 | for (i = 0; i < nmacs; i++) { |
32874aea |
3063 | if (in_commasep_string(maclist[i]->name, str, len)) { |
3064 | scmac_tobe = maclist[i]; |
3065 | break; |
3066 | } |
e5574168 |
3067 | } |
3068 | ssh2_pkt_getstring(&str, &len); /* client->server compression */ |
32874aea |
3069 | for (i = 0; i < lenof(compressions) + 1; i++) { |
3070 | const struct ssh_compress *c = |
3071 | i == 0 ? preferred_comp : compressions[i - 1]; |
3072 | if (in_commasep_string(c->name, str, len)) { |
3073 | cscomp_tobe = c; |
3074 | break; |
3075 | } |
e5574168 |
3076 | } |
3077 | ssh2_pkt_getstring(&str, &len); /* server->client compression */ |
32874aea |
3078 | for (i = 0; i < lenof(compressions) + 1; i++) { |
3079 | const struct ssh_compress *c = |
3080 | i == 0 ? preferred_comp : compressions[i - 1]; |
3081 | if (in_commasep_string(c->name, str, len)) { |
3082 | sccomp_tobe = c; |
3083 | break; |
3084 | } |
e5574168 |
3085 | } |
e5574168 |
3086 | |
3087 | /* |
7bd5a860 |
3088 | * Work out the number of bits of key we will need from the key |
3089 | * exchange. We start with the maximum key length of either |
3090 | * cipher... |
3091 | */ |
3092 | { |
32874aea |
3093 | int csbits, scbits; |
7bd5a860 |
3094 | |
3095 | csbits = cscipher_tobe->keylen; |
3096 | scbits = sccipher_tobe->keylen; |
3097 | nbits = (csbits > scbits ? csbits : scbits); |
3098 | } |
3099 | /* The keys only have 160-bit entropy, since they're based on |
3100 | * a SHA-1 hash. So cap the key size at 160 bits. */ |
32874aea |
3101 | if (nbits > 160) |
3102 | nbits = 160; |
7bd5a860 |
3103 | |
3104 | /* |
a92dd380 |
3105 | * If we're doing Diffie-Hellman group exchange, start by |
3106 | * requesting a group. |
e5574168 |
3107 | */ |
a92dd380 |
3108 | if (kex == &ssh_diffiehellman_gex) { |
32874aea |
3109 | logevent("Doing Diffie-Hellman group exchange"); |
3110 | /* |
3111 | * Work out how big a DH group we will need to allow that |
3112 | * much data. |
7bd5a860 |
3113 | */ |
32874aea |
3114 | pbits = 512 << ((nbits - 1) / 64); |
3115 | ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST); |
3116 | ssh2_pkt_adduint32(pbits); |
3117 | ssh2_pkt_send(); |
3118 | |
3119 | crWaitUntil(ispkt); |
3120 | if (pktin.type != SSH2_MSG_KEX_DH_GEX_GROUP) { |
3121 | bombout(("expected key exchange group packet from server")); |
3122 | crReturn(0); |
3123 | } |
3124 | p = ssh2_pkt_getmp(); |
3125 | g = ssh2_pkt_getmp(); |
3126 | dh_setup_group(p, g); |
3127 | kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT; |
3128 | kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY; |
a92dd380 |
3129 | } else { |
32874aea |
3130 | dh_setup_group1(); |
3131 | kex_init_value = SSH2_MSG_KEXDH_INIT; |
3132 | kex_reply_value = SSH2_MSG_KEXDH_REPLY; |
8d5de777 |
3133 | } |
e5574168 |
3134 | |
a92dd380 |
3135 | logevent("Doing Diffie-Hellman key exchange"); |
e5574168 |
3136 | /* |
a92dd380 |
3137 | * Now generate and send e for Diffie-Hellman. |
e5574168 |
3138 | */ |
32874aea |
3139 | e = dh_create_e(nbits * 2); |
a92dd380 |
3140 | ssh2_pkt_init(kex_init_value); |
e5574168 |
3141 | ssh2_pkt_addmp(e); |
3142 | ssh2_pkt_send(); |
3143 | |
3144 | crWaitUntil(ispkt); |
a92dd380 |
3145 | if (pktin.type != kex_reply_value) { |
32874aea |
3146 | bombout(("expected key exchange reply packet from server")); |
3147 | crReturn(0); |
7cca0d81 |
3148 | } |
e5574168 |
3149 | ssh2_pkt_getstring(&hostkeydata, &hostkeylen); |
3150 | f = ssh2_pkt_getmp(); |
e5574168 |
3151 | ssh2_pkt_getstring(&sigdata, &siglen); |
3152 | |
3153 | K = dh_find_K(f); |
e5574168 |
3154 | |
3155 | sha_string(&exhash, hostkeydata, hostkeylen); |
a92dd380 |
3156 | if (kex == &ssh_diffiehellman_gex) { |
32874aea |
3157 | sha_uint32(&exhash, pbits); |
3158 | sha_mpint(&exhash, p); |
3159 | sha_mpint(&exhash, g); |
a92dd380 |
3160 | } |
e5574168 |
3161 | sha_mpint(&exhash, e); |
3162 | sha_mpint(&exhash, f); |
3163 | sha_mpint(&exhash, K); |
3164 | SHA_Final(&exhash, exchange_hash); |
3165 | |
3709bfe9 |
3166 | dh_cleanup(); |
3167 | |
7cca0d81 |
3168 | #if 0 |
765c4200 |
3169 | debug(("Exchange hash is:\n")); |
3170 | dmemdump(exchange_hash, 20); |
7cca0d81 |
3171 | #endif |
3172 | |
e055a386 |
3173 | hkey = hostkey->newkey(hostkeydata, hostkeylen); |
f7259d10 |
3174 | if (!hkey || |
3175 | !hostkey->verifysig(hkey, sigdata, siglen, exchange_hash, 20)) { |
3176 | bombout(("Server's host key did not match the signature supplied")); |
32874aea |
3177 | crReturn(0); |
8d5de777 |
3178 | } |
e5574168 |
3179 | |
3180 | /* |
7cca0d81 |
3181 | * Expect SSH2_MSG_NEWKEYS from server. |
d39f364a |
3182 | */ |
7cca0d81 |
3183 | crWaitUntil(ispkt); |
8d5de777 |
3184 | if (pktin.type != SSH2_MSG_NEWKEYS) { |
32874aea |
3185 | bombout(("expected new-keys packet from server")); |
3186 | crReturn(0); |
8d5de777 |
3187 | } |
d39f364a |
3188 | |
3189 | /* |
7cca0d81 |
3190 | * Authenticate remote host: verify host key. (We've already |
3191 | * checked the signature of the exchange hash.) |
e5574168 |
3192 | */ |
e055a386 |
3193 | keystr = hostkey->fmtkey(hkey); |
3194 | fingerprint = hostkey->fingerprint(hkey); |
d4857987 |
3195 | verify_ssh_host_key(savedhost, savedport, hostkey->keytype, |
32874aea |
3196 | keystr, fingerprint); |
3197 | if (first_kex) { /* don't bother logging this in rekeys */ |
5e0d7cb8 |
3198 | logevent("Host key fingerprint is:"); |
3199 | logevent(fingerprint); |
3200 | } |
dcbde236 |
3201 | sfree(fingerprint); |
3202 | sfree(keystr); |
e055a386 |
3203 | hostkey->freekey(hkey); |
d39f364a |
3204 | |
3205 | /* |
7cca0d81 |
3206 | * Send SSH2_MSG_NEWKEYS. |
d39f364a |
3207 | */ |
3208 | ssh2_pkt_init(SSH2_MSG_NEWKEYS); |
3209 | ssh2_pkt_send(); |
d39f364a |
3210 | |
3211 | /* |
3212 | * Create and initialise session keys. |
3213 | */ |
3214 | cscipher = cscipher_tobe; |
3215 | sccipher = sccipher_tobe; |
3216 | csmac = csmac_tobe; |
3217 | scmac = scmac_tobe; |
3218 | cscomp = cscomp_tobe; |
3219 | sccomp = sccomp_tobe; |
4ba9b64b |
3220 | cscomp->compress_init(); |
3221 | sccomp->decompress_init(); |
d39f364a |
3222 | /* |
5e0d7cb8 |
3223 | * Set IVs after keys. Here we use the exchange hash from the |
3224 | * _first_ key exchange. |
d39f364a |
3225 | */ |
5e0d7cb8 |
3226 | if (first_kex) |
65a22376 |
3227 | memcpy(ssh2_session_id, exchange_hash, sizeof(exchange_hash)); |
3228 | ssh2_mkkey(K, exchange_hash, ssh2_session_id, 'C', keyspace); |
5e0d7cb8 |
3229 | cscipher->setcskey(keyspace); |
65a22376 |
3230 | ssh2_mkkey(K, exchange_hash, ssh2_session_id, 'D', keyspace); |
5e0d7cb8 |
3231 | sccipher->setsckey(keyspace); |
65a22376 |
3232 | ssh2_mkkey(K, exchange_hash, ssh2_session_id, 'A', keyspace); |
5e0d7cb8 |
3233 | cscipher->setcsiv(keyspace); |
65a22376 |
3234 | ssh2_mkkey(K, exchange_hash, ssh2_session_id, 'B', keyspace); |
5e0d7cb8 |
3235 | sccipher->setsciv(keyspace); |
65a22376 |
3236 | ssh2_mkkey(K, exchange_hash, ssh2_session_id, 'E', keyspace); |
5e0d7cb8 |
3237 | csmac->setcskey(keyspace); |
65a22376 |
3238 | ssh2_mkkey(K, exchange_hash, ssh2_session_id, 'F', keyspace); |
5e0d7cb8 |
3239 | scmac->setsckey(keyspace); |
d39f364a |
3240 | |
033b4cef |
3241 | /* |
0db56f73 |
3242 | * If this is the first key exchange phase, we must pass the |
3243 | * SSH2_MSG_NEWKEYS packet to the next layer, not because it |
3244 | * wants to see it but because it will need time to initialise |
3245 | * itself before it sees an actual packet. In subsequent key |
3246 | * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because |
3247 | * it would only confuse the layer above. |
3248 | */ |
3249 | if (!first_kex) { |
32874aea |
3250 | crReturn(0); |
0db56f73 |
3251 | } |
3252 | first_kex = 0; |
3253 | |
3254 | /* |
7cca0d81 |
3255 | * Now we're encrypting. Begin returning 1 to the protocol main |
3256 | * function so that other things can run on top of the |
3257 | * transport. If we ever see a KEXINIT, we must go back to the |
3258 | * start. |
033b4cef |
3259 | */ |
e96adf72 |
3260 | while (!(ispkt && pktin.type == SSH2_MSG_KEXINIT)) { |
32874aea |
3261 | crReturn(1); |
e96adf72 |
3262 | } |
5e0d7cb8 |
3263 | logevent("Server initiated key re-exchange"); |
7cca0d81 |
3264 | goto begin_key_exchange; |
e5574168 |
3265 | |
3266 | crFinish(1); |
3267 | } |
3268 | |
7cca0d81 |
3269 | /* |
783415f8 |
3270 | * Add data to an SSH2 channel output buffer. |
3271 | */ |
32874aea |
3272 | static void ssh2_add_channel_data(struct ssh_channel *c, char *buf, |
3273 | int len) |
3274 | { |
3275 | if (c->v2.outbufsize < c->v2.outbuflen + len) { |
3276 | c->v2.outbufsize = c->v2.outbuflen + len + 1024; |
3277 | c->v2.outbuffer = srealloc(c->v2.outbuffer, c->v2.outbufsize); |
3278 | } |
3279 | memcpy(c->v2.outbuffer + c->v2.outbuflen, buf, len); |
783415f8 |
3280 | c->v2.outbuflen += len; |
3281 | } |
3282 | |
3283 | /* |
3284 | * Attempt to send data on an SSH2 channel. |
3285 | */ |
32874aea |
3286 | static void ssh2_try_send(struct ssh_channel *c) |
3287 | { |
3288 | while (c->v2.remwindow > 0 && c->v2.outbuflen > 0) { |
3289 | unsigned len = c->v2.remwindow; |
3290 | if (len > c->v2.outbuflen) |
3291 | len = c->v2.outbuflen; |
3292 | if (len > c->v2.remmaxpkt) |
3293 | len = c->v2.remmaxpkt; |
3294 | ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA); |
3295 | ssh2_pkt_adduint32(c->remoteid); |
3296 | ssh2_pkt_addstring_start(); |
3297 | ssh2_pkt_addstring_data(c->v2.outbuffer, len); |
3298 | ssh2_pkt_send(); |
3299 | c->v2.outbuflen -= len; |
3300 | memmove(c->v2.outbuffer, c->v2.outbuffer + len, c->v2.outbuflen); |
3301 | c->v2.remwindow -= len; |
783415f8 |
3302 | } |
3303 | } |
3304 | |
3305 | /* |
7cca0d81 |
3306 | * Handle the SSH2 userauth and connection layers. |
3307 | */ |
3308 | static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) |
3309 | { |
65a22376 |
3310 | static enum { |
32874aea |
3311 | AUTH_INVALID, AUTH_PUBLICKEY_AGENT, AUTH_PUBLICKEY_FILE, |
761187b6 |
3312 | AUTH_PASSWORD, |
3313 | AUTH_KEYBOARD_INTERACTIVE |
65a22376 |
3314 | } method; |
1408a877 |
3315 | static enum { |
32874aea |
3316 | AUTH_TYPE_NONE, |
3317 | AUTH_TYPE_PUBLICKEY, |
3318 | AUTH_TYPE_PUBLICKEY_OFFER_LOUD, |
3319 | AUTH_TYPE_PUBLICKEY_OFFER_QUIET, |
761187b6 |
3320 | AUTH_TYPE_PASSWORD, |
4bdf7c46 |
3321 | AUTH_TYPE_KEYBOARD_INTERACTIVE, |
3322 | AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET |
1408a877 |
3323 | } type; |
761187b6 |
3324 | static int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter; |
3325 | static int tried_pubkey_config, tried_agent, tried_keyb_inter; |
1408a877 |
3326 | static int we_are_in; |
761187b6 |
3327 | static int num_prompts, echo; |
65a22376 |
3328 | static char username[100]; |
3329 | static char pwprompt[200]; |
3330 | static char password[100]; |
7cca0d81 |
3331 | |
e5574168 |
3332 | crBegin; |
3333 | |
7cca0d81 |
3334 | /* |
3335 | * Request userauth protocol, and await a response to it. |
3336 | */ |
3337 | ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST); |
3338 | ssh2_pkt_addstring("ssh-userauth"); |
3339 | ssh2_pkt_send(); |
3340 | crWaitUntilV(ispkt); |
8d5de777 |
3341 | if (pktin.type != SSH2_MSG_SERVICE_ACCEPT) { |
32874aea |
3342 | bombout(("Server refused user authentication protocol")); |
3343 | crReturnV; |
8d5de777 |
3344 | } |
7cca0d81 |
3345 | |
3346 | /* |
1408a877 |
3347 | * We repeat this whole loop, including the username prompt, |
3348 | * until we manage a successful authentication. If the user |
3349 | * types the wrong _password_, they are sent back to the |
3350 | * beginning to try another username. (If they specify a |
3351 | * username in the config, they are never asked, even if they |
3352 | * do give a wrong password.) |
3353 | * |
3354 | * I think this best serves the needs of |
3355 | * |
3356 | * - the people who have no configuration, no keys, and just |
3357 | * want to try repeated (username,password) pairs until they |
3358 | * type both correctly |
3359 | * |
3360 | * - people who have keys and configuration but occasionally |
3361 | * need to fall back to passwords |
3362 | * |
3363 | * - people with a key held in Pageant, who might not have |
3364 | * logged in to a particular machine before; so they want to |
3365 | * type a username, and then _either_ their key will be |
3366 | * accepted, _or_ they will type a password. If they mistype |
3367 | * the username they will want to be able to get back and |
3368 | * retype it! |
7cca0d81 |
3369 | */ |
1408a877 |
3370 | do { |
3371 | static int pos; |
7cca0d81 |
3372 | static char c; |
e5574168 |
3373 | |
1408a877 |
3374 | /* |
3375 | * Get a username. |
3376 | */ |
3377 | pos = 0; |
67779be7 |
3378 | if ((flags & FLAG_INTERACTIVE) && !*cfg.username) { |
32874aea |
3379 | if (ssh_get_line) { |
3380 | if (!ssh_get_line("login as: ", |
3381 | username, sizeof(username), FALSE)) { |
3382 | /* |
3383 | * get_line failed to get a username. |
3384 | * Terminate. |
3385 | */ |
3386 | logevent("No username provided. Abandoning session."); |
3387 | ssh_state = SSH_STATE_CLOSED; |
3388 | crReturnV; |
3389 | } |
3390 | } else { |
3391 | c_write_str("login as: "); |
3392 | ssh_send_ok = 1; |
3393 | while (pos >= 0) { |
3394 | crWaitUntilV(!ispkt); |
3395 | while (inlen--) |
3396 | switch (c = *in++) { |
3397 | case 10: |
3398 | case 13: |
3399 | username[pos] = 0; |
3400 | pos = -1; |
3401 | break; |
3402 | case 8: |
3403 | case 127: |
3404 | if (pos > 0) { |
3405 | c_write_str("\b \b"); |
3406 | pos--; |
3407 | } |
3408 | break; |
3409 | case 21: |
3410 | case 27: |
3411 | while (pos > 0) { |
3412 | c_write_str("\b \b"); |
3413 | pos--; |
3414 | } |
3415 | break; |
3416 | case 3: |
3417 | case 4: |
3418 | random_save_seed(); |
3419 | exit(0); |
3420 | break; |
3421 | default: |
3422 | if (((c >= ' ' && c <= '~') || |
51b2fb65 |
3423 | ((unsigned char) c >= 160)) |
3424 | && pos < sizeof(username)-1) { |
32874aea |
3425 | username[pos++] = c; |
3426 | c_write(&c, 1); |
3427 | } |
3428 | break; |
3429 | } |
3430 | } |
3431 | } |
1408a877 |
3432 | c_write_str("\r\n"); |
7cca0d81 |
3433 | username[strcspn(username, "\n\r")] = '\0'; |
3434 | } else { |
3435 | char stuff[200]; |
3436 | strncpy(username, cfg.username, 99); |
3437 | username[99] = '\0'; |
65a22376 |
3438 | if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) { |
7cca0d81 |
3439 | sprintf(stuff, "Using username \"%s\".\r\n", username); |
1408a877 |
3440 | c_write_str(stuff); |
7cca0d81 |
3441 | } |
3442 | } |
3443 | |
65a22376 |
3444 | /* |
1408a877 |
3445 | * Send an authentication request using method "none": (a) |
3446 | * just in case it succeeds, and (b) so that we know what |
3447 | * authentication methods we can usefully try next. |
65a22376 |
3448 | */ |
1408a877 |
3449 | ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST); |
3450 | ssh2_pkt_addstring(username); |
32874aea |
3451 | ssh2_pkt_addstring("ssh-connection"); /* service requested */ |
1408a877 |
3452 | ssh2_pkt_addstring("none"); /* method */ |
3453 | ssh2_pkt_send(); |
3454 | type = AUTH_TYPE_NONE; |
3455 | gotit = FALSE; |
3456 | we_are_in = FALSE; |
7cca0d81 |
3457 | |
1408a877 |
3458 | tried_pubkey_config = FALSE; |
1983e559 |
3459 | tried_agent = FALSE; |
65a22376 |
3460 | |
1408a877 |
3461 | while (1) { |
3462 | /* |
3463 | * Wait for the result of the last authentication request. |
3464 | */ |
3465 | if (!gotit) |
3466 | crWaitUntilV(ispkt); |
3467 | while (pktin.type == SSH2_MSG_USERAUTH_BANNER) { |
32874aea |
3468 | char *banner; |
3469 | int size; |
3470 | /* |
3471 | * Don't show the banner if we're operating in |
3472 | * non-verbose non-interactive mode. (It's probably |
3473 | * a script, which means nobody will read the |
3474 | * banner _anyway_, and moreover the printing of |
3475 | * the banner will screw up processing on the |
3476 | * output of (say) plink.) |
3477 | */ |
3478 | if (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE)) { |
3479 | ssh2_pkt_getstring(&banner, &size); |
3480 | if (banner) |
3481 | c_write_untrusted(banner, size); |
3482 | } |
1408a877 |
3483 | crWaitUntilV(ispkt); |
3484 | } |
3485 | if (pktin.type == SSH2_MSG_USERAUTH_SUCCESS) { |
3486 | logevent("Access granted"); |
3487 | we_are_in = TRUE; |
3488 | break; |
3489 | } |
65a22376 |
3490 | |
1408a877 |
3491 | if (pktin.type != SSH2_MSG_USERAUTH_FAILURE) { |
32874aea |
3492 | bombout( |
3493 | ("Strange packet received during authentication: type %d", |
1408a877 |
3494 | pktin.type)); |
38c4a8da |
3495 | crReturnV; |
65a22376 |
3496 | } |
3497 | |
1408a877 |
3498 | gotit = FALSE; |
65a22376 |
3499 | |
1408a877 |
3500 | /* |
3501 | * OK, we're now sitting on a USERAUTH_FAILURE message, so |
3502 | * we can look at the string in it and know what we can |
3503 | * helpfully try next. |
3504 | */ |
3505 | { |
3506 | char *methods; |
3507 | int methlen; |
3508 | ssh2_pkt_getstring(&methods, &methlen); |
3509 | if (!ssh2_pkt_getbool()) { |
3510 | /* |
3511 | * We have received an unequivocal Access |
3512 | * Denied. This can translate to a variety of |
3513 | * messages: |
3514 | * |
3515 | * - if we'd just tried "none" authentication, |
3516 | * it's not worth printing anything at all |
3517 | * |
3518 | * - if we'd just tried a public key _offer_, |
3519 | * the message should be "Server refused our |
3520 | * key" (or no message at all if the key |
3521 | * came from Pageant) |
3522 | * |
3523 | * - if we'd just tried anything else, the |
3524 | * message really should be "Access denied". |
3525 | * |
3526 | * Additionally, if we'd just tried password |
3527 | * authentication, we should break out of this |
3528 | * whole loop so as to go back to the username |
3529 | * prompt. |
3530 | */ |
3531 | if (type == AUTH_TYPE_NONE) { |
3532 | /* do nothing */ |
3533 | } else if (type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD || |
3534 | type == AUTH_TYPE_PUBLICKEY_OFFER_QUIET) { |
3535 | if (type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD) |
3536 | c_write_str("Server refused our key\r\n"); |
3537 | logevent("Server refused public key"); |
4bdf7c46 |
3538 | } else if (type == AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET) { |
3539 | /* server declined keyboard-interactive; ignore */ |
1408a877 |
3540 | } else { |
3541 | c_write_str("Access denied\r\n"); |
3542 | logevent("Access denied"); |
3543 | if (type == AUTH_TYPE_PASSWORD) { |
3544 | we_are_in = FALSE; |
3545 | break; |
3546 | } |
3547 | } |
3548 | } else { |
3549 | c_write_str("Further authentication required\r\n"); |
3550 | logevent("Further authentication required"); |
3551 | } |
65a22376 |
3552 | |
32874aea |
3553 | can_pubkey = |
3554 | in_commasep_string("publickey", methods, methlen); |
3555 | can_passwd = |
3556 | in_commasep_string("password", methods, methlen); |
761187b6 |
3557 | can_passwd = |
3558 | in_commasep_string("password", methods, methlen); |
3559 | can_keyb_inter = |
3560 | in_commasep_string("keyboard-interactive", methods, methlen); |
1408a877 |
3561 | } |
65a22376 |
3562 | |
1408a877 |
3563 | method = 0; |
65a22376 |
3564 | |
761187b6 |
3565 | if (!method && can_keyb_inter && !tried_keyb_inter) { |
3566 | method = AUTH_KEYBOARD_INTERACTIVE; |
3567 | type = AUTH_TYPE_KEYBOARD_INTERACTIVE; |
3568 | tried_keyb_inter = TRUE; |
3569 | |
3570 | ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST); |
3571 | ssh2_pkt_addstring(username); |
3572 | ssh2_pkt_addstring("ssh-connection"); /* service requested */ |
3573 | ssh2_pkt_addstring("keyboard-interactive"); /* method */ |
3574 | ssh2_pkt_addstring(""); /* lang */ |
3575 | ssh2_pkt_addstring(""); |
3576 | ssh2_pkt_send(); |
3577 | |
3578 | crWaitUntilV(ispkt); |
3579 | if (pktin.type != SSH2_MSG_USERAUTH_INFO_REQUEST) { |
3580 | if (pktin.type == SSH2_MSG_USERAUTH_FAILURE) |
3581 | gotit = TRUE; |
3582 | logevent("Keyboard-interactive authentication refused"); |
4bdf7c46 |
3583 | type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET; |
761187b6 |
3584 | continue; |
3585 | } |
3586 | |
3587 | /* We've got packet with that "interactive" info |
3588 | dump banners, and set its prompt as ours */ |
3589 | { |
3590 | char *name, *inst, *lang, *prompt; |
3591 | int name_len, inst_len, lang_len, prompt_len; |
3592 | ssh2_pkt_getstring(&name, &name_len); |
3593 | ssh2_pkt_getstring(&inst, &inst_len); |
3594 | ssh2_pkt_getstring(&lang, &lang_len); |
3595 | if (name_len > 0) |
3596 | c_write_untrusted(name, name_len); |
3597 | if (inst_len > 0) |
3598 | c_write_untrusted(inst, inst_len); |
3599 | num_prompts = ssh2_pkt_getuint32(); |
3600 | |
3601 | ssh2_pkt_getstring(&prompt, &prompt_len); |
3602 | strncpy(pwprompt, prompt, sizeof(pwprompt)); |
3603 | need_pw = TRUE; |
3604 | |
3605 | echo = ssh2_pkt_getbool(); |
3606 | } |
3607 | } |
3608 | |
78afa559 |
3609 | if (!method && can_pubkey && agent_exists() && !tried_agent) { |
1983e559 |
3610 | /* |
3611 | * Attempt public-key authentication using Pageant. |
3612 | */ |
3613 | static unsigned char request[5], *response, *p; |
3614 | static int responselen; |
3615 | static int i, nkeys; |
3616 | static int authed = FALSE; |
3617 | void *r; |
3618 | |
3619 | tried_agent = TRUE; |
3620 | |
3621 | logevent("Pageant is running. Requesting keys."); |
3622 | |
3623 | /* Request the keys held by the agent. */ |
3624 | PUT_32BIT(request, 1); |
3625 | request[4] = SSH2_AGENTC_REQUEST_IDENTITIES; |
3626 | agent_query(request, 5, &r, &responselen); |
32874aea |
3627 | response = (unsigned char *) r; |
95797139 |
3628 | if (response && responselen >= 5 && |
32874aea |
3629 | response[4] == SSH2_AGENT_IDENTITIES_ANSWER) { |
1983e559 |
3630 | p = response + 5; |
32874aea |
3631 | nkeys = GET_32BIT(p); |
3632 | p += 4; |
3633 | { |
3634 | char buf[64]; |
3635 | sprintf(buf, "Pageant has %d SSH2 keys", nkeys); |
3636 | logevent(buf); |
3637 | } |
1983e559 |
3638 | for (i = 0; i < nkeys; i++) { |
3639 | static char *pkblob, *alg, *commentp; |
3640 | static int pklen, alglen, commentlen; |
3641 | static int siglen, retlen, len; |
3642 | static char *q, *agentreq, *ret; |
2d466ffd |
3643 | void *vret; |
1983e559 |
3644 | |
32874aea |
3645 | { |
3646 | char buf[64]; |
3647 | sprintf(buf, "Trying Pageant key #%d", i); |
3648 | logevent(buf); |
3649 | } |
3650 | pklen = GET_32BIT(p); |
3651 | p += 4; |
3652 | pkblob = p; |
3653 | p += pklen; |
1983e559 |
3654 | alglen = GET_32BIT(pkblob); |
3655 | alg = pkblob + 4; |
32874aea |
3656 | commentlen = GET_32BIT(p); |
3657 | p += 4; |
3658 | commentp = p; |
3659 | p += commentlen; |
1983e559 |
3660 | ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST); |
3661 | ssh2_pkt_addstring(username); |
32874aea |
3662 | ssh2_pkt_addstring("ssh-connection"); /* service requested */ |
3663 | ssh2_pkt_addstring("publickey"); /* method */ |
3664 | ssh2_pkt_addbool(FALSE); /* no signature included */ |
1983e559 |
3665 | ssh2_pkt_addstring_start(); |
3666 | ssh2_pkt_addstring_data(alg, alglen); |
3667 | ssh2_pkt_addstring_start(); |
3668 | ssh2_pkt_addstring_data(pkblob, pklen); |
3669 | ssh2_pkt_send(); |
3670 | |
3671 | crWaitUntilV(ispkt); |
3672 | if (pktin.type != SSH2_MSG_USERAUTH_PK_OK) { |
3673 | logevent("Key refused"); |
3674 | continue; |
3675 | } |
3676 | |
32874aea |
3677 | if (flags & FLAG_VERBOSE) { |
3678 | c_write_str |
3679 | ("Authenticating with public key \""); |
3680 | c_write(commentp, commentlen); |
3681 | c_write_str("\" from agent\r\n"); |
3682 | } |
1983e559 |
3683 | |
3684 | /* |
3685 | * Server is willing to accept the key. |
3686 | * Construct a SIGN_REQUEST. |
3687 | */ |
3688 | ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST); |
3689 | ssh2_pkt_addstring(username); |
32874aea |
3690 | ssh2_pkt_addstring("ssh-connection"); /* service requested */ |
3691 | ssh2_pkt_addstring("publickey"); /* method */ |
1983e559 |
3692 | ssh2_pkt_addbool(TRUE); |
3693 | ssh2_pkt_addstring_start(); |
3694 | ssh2_pkt_addstring_data(alg, alglen); |
3695 | ssh2_pkt_addstring_start(); |
3696 | ssh2_pkt_addstring_data(pkblob, pklen); |
3697 | |
3698 | siglen = pktout.length - 5 + 4 + 20; |
32874aea |
3699 | len = 1; /* message type */ |
3700 | len += 4 + pklen; /* key blob */ |
3701 | len += 4 + siglen; /* data to sign */ |
3702 | len += 4; /* flags */ |
1983e559 |
3703 | agentreq = smalloc(4 + len); |
3704 | PUT_32BIT(agentreq, len); |
3705 | q = agentreq + 4; |
3706 | *q++ = SSH2_AGENTC_SIGN_REQUEST; |
32874aea |
3707 | PUT_32BIT(q, pklen); |
3708 | q += 4; |
3709 | memcpy(q, pkblob, pklen); |
3710 | q += pklen; |
3711 | PUT_32BIT(q, siglen); |
3712 | q += 4; |
1983e559 |
3713 | /* Now the data to be signed... */ |
32874aea |
3714 | PUT_32BIT(q, 20); |
3715 | q += 4; |
3716 | memcpy(q, ssh2_session_id, 20); |
3717 | q += 20; |
3718 | memcpy(q, pktout.data + 5, pktout.length - 5); |
3719 | q += pktout.length - 5; |
1983e559 |
3720 | /* And finally the (zero) flags word. */ |
3721 | PUT_32BIT(q, 0); |
2d466ffd |
3722 | agent_query(agentreq, len + 4, &vret, &retlen); |
3723 | ret = vret; |
1983e559 |
3724 | sfree(agentreq); |
3725 | if (ret) { |
3726 | if (ret[4] == SSH2_AGENT_SIGN_RESPONSE) { |
3727 | logevent("Sending Pageant's response"); |
3728 | ssh2_pkt_addstring_start(); |
32874aea |
3729 | ssh2_pkt_addstring_data(ret + 9, |
3730 | GET_32BIT(ret + |
3731 | 5)); |
1983e559 |
3732 | ssh2_pkt_send(); |
3733 | authed = TRUE; |
3734 | break; |
3735 | } else { |
32874aea |
3736 | logevent |
3737 | ("Pageant failed to answer challenge"); |
1983e559 |
3738 | sfree(ret); |
3739 | } |
3740 | } |
3741 | } |
3742 | if (authed) |
3743 | continue; |
3744 | } |
3745 | } |
3746 | |
32874aea |
3747 | if (!method && can_pubkey && *cfg.keyfile |
3748 | && !tried_pubkey_config) { |
1408a877 |
3749 | unsigned char *pub_blob; |
3750 | char *algorithm, *comment; |
3751 | int pub_blob_len; |
65a22376 |
3752 | |
1408a877 |
3753 | tried_pubkey_config = TRUE; |
65a22376 |
3754 | |
65a22376 |
3755 | /* |
1408a877 |
3756 | * Try the public key supplied in the configuration. |
3757 | * |
3758 | * First, offer the public blob to see if the server is |
3759 | * willing to accept it. |
65a22376 |
3760 | */ |
1408a877 |
3761 | pub_blob = ssh2_userkey_loadpub(cfg.keyfile, &algorithm, |
3762 | &pub_blob_len); |
3763 | if (pub_blob) { |
3764 | ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST); |
3765 | ssh2_pkt_addstring(username); |
32874aea |
3766 | ssh2_pkt_addstring("ssh-connection"); /* service requested */ |
3767 | ssh2_pkt_addstring("publickey"); /* method */ |
3768 | ssh2_pkt_addbool(FALSE); /* no signature included */ |
1408a877 |
3769 | ssh2_pkt_addstring(algorithm); |
3770 | ssh2_pkt_addstring_start(); |
3771 | ssh2_pkt_addstring_data(pub_blob, pub_blob_len); |
3772 | ssh2_pkt_send(); |
32874aea |
3773 | logevent("Offered public key"); /* FIXME */ |
1408a877 |
3774 | |
3775 | crWaitUntilV(ispkt); |
3776 | if (pktin.type != SSH2_MSG_USERAUTH_PK_OK) { |
3777 | gotit = TRUE; |
3778 | type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD; |
32874aea |
3779 | continue; /* key refused; give up on it */ |
1408a877 |
3780 | } |
65a22376 |
3781 | |
1408a877 |
3782 | logevent("Offer of public key accepted"); |
65a22376 |
3783 | /* |
1408a877 |
3784 | * Actually attempt a serious authentication using |
3785 | * the key. |
65a22376 |
3786 | */ |
1408a877 |
3787 | if (ssh2_userkey_encrypted(cfg.keyfile, &comment)) { |
32874aea |
3788 | sprintf(pwprompt, |
3789 | "Passphrase for key \"%.100s\": ", |
3790 | comment); |
1408a877 |
3791 | need_pw = TRUE; |
3792 | } else { |
3793 | need_pw = FALSE; |
3794 | } |
3795 | c_write_str("Authenticating with public key \""); |
3796 | c_write_str(comment); |
3797 | c_write_str("\"\r\n"); |
3798 | method = AUTH_PUBLICKEY_FILE; |
65a22376 |
3799 | } |
1408a877 |
3800 | } |
3801 | |
3802 | if (!method && can_passwd) { |
3803 | method = AUTH_PASSWORD; |
32874aea |
3804 | sprintf(pwprompt, "%.90s@%.90s's password: ", username, |
3805 | savedhost); |
1408a877 |
3806 | need_pw = TRUE; |
3807 | } |
3808 | |
3809 | if (need_pw) { |
fa17a66e |
3810 | if (ssh_get_line) { |
3811 | if (!ssh_get_line(pwprompt, password, |
32874aea |
3812 | sizeof(password), TRUE)) { |
1408a877 |
3813 | /* |
fa17a66e |
3814 | * get_line failed to get a password (for |
3815 | * example because one was supplied on the |
3816 | * command line which has already failed to |
3817 | * work). Terminate. |
1408a877 |
3818 | */ |
2bc6a386 |
3819 | ssh2_pkt_init(SSH2_MSG_DISCONNECT); |
3820 | ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION); |
3821 | ssh2_pkt_addstring |
3822 | ("No more passwords available to try"); |
3823 | ssh2_pkt_addstring("en"); /* language tag */ |
3824 | ssh2_pkt_send(); |
3825 | connection_fatal("Unable to authenticate"); |
1408a877 |
3826 | ssh_state = SSH_STATE_CLOSED; |
3827 | crReturnV; |
3828 | } |
3829 | } else { |
3830 | static int pos = 0; |
3831 | static char c; |
3832 | |
761187b6 |
3833 | c_write_untrusted(pwprompt, strlen(pwprompt)); |
1408a877 |
3834 | ssh_send_ok = 1; |
3835 | |
3836 | pos = 0; |
3837 | while (pos >= 0) { |
3838 | crWaitUntilV(!ispkt); |
32874aea |
3839 | while (inlen--) |
3840 | switch (c = *in++) { |
3841 | case 10: |
3842 | case 13: |
3843 | password[pos] = 0; |
3844 | pos = -1; |
3845 | break; |
3846 | case 8: |
3847 | case 127: |
3848 | if (pos > 0) |
3849 | pos--; |
3850 | break; |
3851 | case 21: |
3852 | case 27: |
3853 | pos = 0; |
3854 | break; |
3855 | case 3: |
3856 | case 4: |
3857 | random_save_seed(); |
3858 | exit(0); |
3859 | break; |
3860 | default: |
51b2fb65 |
3861 | if (pos < sizeof(password)-1) |
32874aea |
3862 | password[pos++] = c; |
3863 | break; |
3864 | } |
65a22376 |
3865 | } |
1408a877 |
3866 | c_write_str("\r\n"); |
65a22376 |
3867 | } |
65a22376 |
3868 | } |
65a22376 |
3869 | |
1408a877 |
3870 | if (method == AUTH_PUBLICKEY_FILE) { |
3871 | /* |
3872 | * We have our passphrase. Now try the actual authentication. |
3873 | */ |
3874 | struct ssh2_userkey *key; |
65a22376 |
3875 | |
1408a877 |
3876 | key = ssh2_load_userkey(cfg.keyfile, password); |
3877 | if (key == SSH2_WRONG_PASSPHRASE || key == NULL) { |
3878 | if (key == SSH2_WRONG_PASSPHRASE) { |
3879 | c_write_str("Wrong passphrase\r\n"); |
3880 | tried_pubkey_config = FALSE; |
3881 | } else { |
3882 | c_write_str("Unable to load private key\r\n"); |
3883 | tried_pubkey_config = TRUE; |
3884 | } |
3885 | /* Send a spurious AUTH_NONE to return to the top. */ |
3886 | ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST); |
3887 | ssh2_pkt_addstring(username); |
32874aea |
3888 | ssh2_pkt_addstring("ssh-connection"); /* service requested */ |
3889 | ssh2_pkt_addstring("none"); /* method */ |
1408a877 |
3890 | ssh2_pkt_send(); |
3891 | type = AUTH_TYPE_NONE; |
3892 | } else { |
3893 | unsigned char *blob, *sigdata; |
3894 | int blob_len, sigdata_len; |
65a22376 |
3895 | |
1408a877 |
3896 | /* |
3897 | * We have loaded the private key and the server |
3898 | * has announced that it's willing to accept it. |
3899 | * Hallelujah. Generate a signature and send it. |
3900 | */ |
3901 | ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST); |
3902 | ssh2_pkt_addstring(username); |
32874aea |
3903 | ssh2_pkt_addstring("ssh-connection"); /* service requested */ |
3904 | ssh2_pkt_addstring("publickey"); /* method */ |
1408a877 |
3905 | ssh2_pkt_addbool(TRUE); |
3906 | ssh2_pkt_addstring(key->alg->name); |
3907 | blob = key->alg->public_blob(key->data, &blob_len); |
3908 | ssh2_pkt_addstring_start(); |
3909 | ssh2_pkt_addstring_data(blob, blob_len); |
3910 | sfree(blob); |
3911 | |
3912 | /* |
3913 | * The data to be signed is: |
3914 | * |
3915 | * string session-id |
3916 | * |
3917 | * followed by everything so far placed in the |
3918 | * outgoing packet. |
3919 | */ |
3920 | sigdata_len = pktout.length - 5 + 4 + 20; |
3921 | sigdata = smalloc(sigdata_len); |
3922 | PUT_32BIT(sigdata, 20); |
32874aea |
3923 | memcpy(sigdata + 4, ssh2_session_id, 20); |
3924 | memcpy(sigdata + 24, pktout.data + 5, |
3925 | pktout.length - 5); |
3926 | blob = |
3927 | key->alg->sign(key->data, sigdata, sigdata_len, |
3928 | &blob_len); |
1408a877 |
3929 | ssh2_pkt_addstring_start(); |
3930 | ssh2_pkt_addstring_data(blob, blob_len); |
3931 | sfree(blob); |
3932 | sfree(sigdata); |
3933 | |
3934 | ssh2_pkt_send(); |
3935 | type = AUTH_TYPE_PUBLICKEY; |
3936 | } |
3937 | } else if (method == AUTH_PASSWORD) { |
65a22376 |
3938 | /* |
1408a877 |
3939 | * We send the password packet lumped tightly together with |
3940 | * an SSH_MSG_IGNORE packet. The IGNORE packet contains a |
3941 | * string long enough to make the total length of the two |
3942 | * packets constant. This should ensure that a passive |
3943 | * listener doing traffic analyis can't work out the length |
3944 | * of the password. |
3945 | * |
3946 | * For this to work, we need an assumption about the |
3947 | * maximum length of the password packet. I think 256 is |
3948 | * pretty conservative. Anyone using a password longer than |
3949 | * that probably doesn't have much to worry about from |
3950 | * people who find out how long their password is! |
65a22376 |
3951 | */ |
3952 | ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST); |
3953 | ssh2_pkt_addstring(username); |
32874aea |
3954 | ssh2_pkt_addstring("ssh-connection"); /* service requested */ |
1408a877 |
3955 | ssh2_pkt_addstring("password"); |
3956 | ssh2_pkt_addbool(FALSE); |
3957 | ssh2_pkt_addstring(password); |
3958 | ssh2_pkt_defer(); |
65a22376 |
3959 | /* |
1408a877 |
3960 | * We'll include a string that's an exact multiple of the |
3961 | * cipher block size. If the cipher is NULL for some |
3962 | * reason, we don't do this trick at all because we gain |
3963 | * nothing by it. |
65a22376 |
3964 | */ |
32874aea |
3965 | if (cscipher) { |
3966 | int stringlen, i; |
3967 | |
3968 | stringlen = (256 - deferred_len); |
3969 | stringlen += cscipher->blksize - 1; |
3970 | stringlen -= (stringlen % cscipher->blksize); |
3971 | if (cscomp) { |
3972 | /* |
3973 | * Temporarily disable actual compression, |
3974 | * so we can guarantee to get this string |
3975 | * exactly the length we want it. The |
3976 | * compression-disabling routine should |
3977 | * return an integer indicating how many |
3978 | * bytes we should adjust our string length |
3979 | * by. |
3980 | */ |
3981 | stringlen -= cscomp->disable_compression(); |
3982 | } |
1408a877 |
3983 | ssh2_pkt_init(SSH2_MSG_IGNORE); |
3984 | ssh2_pkt_addstring_start(); |
6e9e9520 |
3985 | for (i = 0; i < stringlen; i++) { |
32874aea |
3986 | char c = (char) random_byte(); |
3987 | ssh2_pkt_addstring_data(&c, 1); |
65a22376 |
3988 | } |
1408a877 |
3989 | ssh2_pkt_defer(); |
65a22376 |
3990 | } |
39065bed |
3991 | ssh_pkt_defersend(); |
0d43337a |
3992 | logevent("Sent password"); |
1408a877 |
3993 | type = AUTH_TYPE_PASSWORD; |
761187b6 |
3994 | } else if (method == AUTH_KEYBOARD_INTERACTIVE) { |
3995 | ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE); |
3996 | ssh2_pkt_adduint32(num_prompts); |
3997 | ssh2_pkt_addstring(password); |
3998 | memset(password, 0, sizeof(password)); |
3999 | ssh2_pkt_send(); |
4000 | type = AUTH_TYPE_KEYBOARD_INTERACTIVE; |
1408a877 |
4001 | } else { |
32874aea |
4002 | c_write_str |
4003 | ("No supported authentication methods left to try!\r\n"); |
4004 | logevent |
4005 | ("No supported authentications offered. Disconnecting"); |
1408a877 |
4006 | ssh2_pkt_init(SSH2_MSG_DISCONNECT); |
4007 | ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION); |
32874aea |
4008 | ssh2_pkt_addstring |
4009 | ("No supported authentication methods available"); |
4010 | ssh2_pkt_addstring("en"); /* language tag */ |
1408a877 |
4011 | ssh2_pkt_send(); |
4012 | ssh_state = SSH_STATE_CLOSED; |
4013 | crReturnV; |
65a22376 |
4014 | } |
65a22376 |
4015 | } |
1408a877 |
4016 | } while (!we_are_in); |
7cca0d81 |
4017 | |
4018 | /* |
4019 | * Now we're authenticated for the connection protocol. The |
4020 | * connection protocol will automatically have started at this |
4021 | * point; there's no need to send SERVICE_REQUEST. |
4022 | */ |
4023 | |
4024 | /* |
4025 | * So now create a channel with a session in it. |
4026 | */ |
d2371c81 |
4027 | ssh_channels = newtree234(ssh_channelcmp); |
dcbde236 |
4028 | mainchan = smalloc(sizeof(struct ssh_channel)); |
d2371c81 |
4029 | mainchan->localid = alloc_channel_id(); |
7cca0d81 |
4030 | ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN); |
4031 | ssh2_pkt_addstring("session"); |
d211621f |
4032 | ssh2_pkt_adduint32(mainchan->localid); |
32874aea |
4033 | ssh2_pkt_adduint32(0x8000UL); /* our window size */ |
4034 | ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */ |
7cca0d81 |
4035 | ssh2_pkt_send(); |
4036 | crWaitUntilV(ispkt); |
4037 | if (pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) { |
32874aea |
4038 | bombout(("Server refused to open a session")); |
4039 | crReturnV; |
4040 | /* FIXME: error data comes back in FAILURE packet */ |
7cca0d81 |
4041 | } |
d211621f |
4042 | if (ssh2_pkt_getuint32() != mainchan->localid) { |
32874aea |
4043 | bombout(("Server's channel confirmation cited wrong channel")); |
4044 | crReturnV; |
7cca0d81 |
4045 | } |
d211621f |
4046 | mainchan->remoteid = ssh2_pkt_getuint32(); |
783415f8 |
4047 | mainchan->type = CHAN_MAINSESSION; |
4048 | mainchan->closes = 0; |
4049 | mainchan->v2.remwindow = ssh2_pkt_getuint32(); |
4050 | mainchan->v2.remmaxpkt = ssh2_pkt_getuint32(); |
4051 | mainchan->v2.outbuffer = NULL; |
4052 | mainchan->v2.outbuflen = mainchan->v2.outbufsize = 0; |
783415f8 |
4053 | add234(ssh_channels, mainchan); |
7cca0d81 |
4054 | logevent("Opened channel for session"); |
4055 | |
4056 | /* |
783415f8 |
4057 | * Potentially enable X11 forwarding. |
4058 | */ |
4059 | if (cfg.x11_forward) { |
32874aea |
4060 | char proto[20], data[64]; |
4061 | logevent("Requesting X11 forwarding"); |
4062 | x11_invent_auth(proto, sizeof(proto), data, sizeof(data)); |
4063 | ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST); |
4064 | ssh2_pkt_adduint32(mainchan->remoteid); |
4065 | ssh2_pkt_addstring("x11-req"); |
4066 | ssh2_pkt_addbool(1); /* want reply */ |
4067 | ssh2_pkt_addbool(0); /* many connections */ |
4068 | ssh2_pkt_addstring(proto); |
4069 | ssh2_pkt_addstring(data); |
4070 | ssh2_pkt_adduint32(0); /* screen number */ |
4071 | ssh2_pkt_send(); |
4072 | |
4073 | do { |
4074 | crWaitUntilV(ispkt); |
4075 | if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) { |
4076 | unsigned i = ssh2_pkt_getuint32(); |
4077 | struct ssh_channel *c; |
4078 | c = find234(ssh_channels, &i, ssh_channelfind); |
4079 | if (!c) |
4080 | continue; /* nonexistent channel */ |
4081 | c->v2.remwindow += ssh2_pkt_getuint32(); |
4082 | } |
4083 | } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST); |
4084 | |
4085 | if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) { |
4086 | if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) { |
4087 | bombout(("Server got confused by X11 forwarding request")); |
4088 | crReturnV; |
4089 | } |
4090 | logevent("X11 forwarding refused"); |
4091 | } else { |
4092 | logevent("X11 forwarding enabled"); |
783415f8 |
4093 | ssh_X11_fwd_enabled = TRUE; |
32874aea |
4094 | } |
783415f8 |
4095 | } |
4096 | |
4097 | /* |
bc240b21 |
4098 | * Enable port forwardings. |
4099 | */ |
4100 | { |
4101 | static char *e; /* preserve across crReturn */ |
4102 | char type; |
4103 | int n; |
4104 | int sport,dport; |
4105 | char sports[256], dports[256], host[256]; |
4106 | char buf[1024]; |
4107 | |
4108 | ssh_rportfwds = newtree234(ssh_rportcmp_ssh2); |
4109 | /* Add port forwardings. */ |
4110 | e = cfg.portfwd; |
4111 | while (*e) { |
4112 | type = *e++; |
4113 | n = 0; |
4114 | while (*e && *e != '\t') |
4115 | sports[n++] = *e++; |
4116 | sports[n] = 0; |
4117 | if (*e == '\t') |
4118 | e++; |
4119 | n = 0; |
4120 | while (*e && *e != ':') |
4121 | host[n++] = *e++; |
4122 | host[n] = 0; |
4123 | if (*e == ':') |
4124 | e++; |
4125 | n = 0; |
4126 | while (*e) |
4127 | dports[n++] = *e++; |
4128 | dports[n] = 0; |
4129 | e++; |
4130 | dport = atoi(dports); |
4131 | sport = atoi(sports); |
4132 | if (sport && dport) { |
4133 | if (type == 'L') { |
4134 | pfd_addforward(host, dport, sport); |
4135 | sprintf(buf, "Local port %d forwarding to %s:%d", |
4136 | sport, host, dport); |
4137 | logevent(buf); |
4138 | } else { |
4139 | struct ssh_rportfwd *pf; |
4140 | pf = smalloc(sizeof(*pf)); |
4141 | strcpy(pf->dhost, host); |
4142 | pf->dport = dport; |
4143 | pf->sport = sport; |
4144 | if (add234(ssh_rportfwds, pf) != pf) { |
4145 | sprintf(buf, |
95bc8819 |
4146 | "Duplicate remote port forwarding to %s:%d", |
bc240b21 |
4147 | host, dport); |
4148 | logevent(buf); |
4149 | sfree(pf); |
4150 | } else { |
4151 | sprintf(buf, "Requesting remote port %d (forwarded to %s:%d)", |
4152 | sport, host, dport); |
4153 | logevent(buf); |
4154 | ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST); |
4155 | ssh2_pkt_addstring("tcpip-forward"); |
4156 | ssh2_pkt_addbool(1);/* want reply */ |
4157 | ssh2_pkt_addstring("127.0.0.1"); |
4158 | ssh2_pkt_adduint32(sport); |
4159 | ssh2_pkt_send(); |
4160 | |
4161 | do { |
4162 | crWaitUntilV(ispkt); |
4163 | if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) { |
4164 | unsigned i = ssh2_pkt_getuint32(); |
4165 | struct ssh_channel *c; |
4166 | c = find234(ssh_channels, &i, ssh_channelfind); |
4167 | if (!c) |
4168 | continue;/* nonexistent channel */ |
4169 | c->v2.remwindow += ssh2_pkt_getuint32(); |
4170 | } |
4171 | } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST); |
4172 | |
4173 | if (pktin.type != SSH2_MSG_REQUEST_SUCCESS) { |
4174 | if (pktin.type != SSH2_MSG_REQUEST_FAILURE) { |
4175 | bombout(("Server got confused by port forwarding request")); |
4176 | crReturnV; |
4177 | } |
4178 | logevent("Server refused this port forwarding"); |
4179 | } else { |
4180 | logevent("Remote port forwarding enabled"); |
4181 | } |
4182 | } |
4183 | } |
4184 | } |
4185 | } |
4186 | } |
4187 | |
4188 | /* |
36c2a3e9 |
4189 | * Potentially enable agent forwarding. |
4190 | */ |
4191 | if (cfg.agentfwd && agent_exists()) { |
32874aea |
4192 | logevent("Requesting OpenSSH-style agent forwarding"); |
4193 | ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST); |
4194 | ssh2_pkt_adduint32(mainchan->remoteid); |
4195 | ssh2_pkt_addstring("auth-agent-req@openssh.com"); |
4196 | ssh2_pkt_addbool(1); /* want reply */ |
4197 | ssh2_pkt_send(); |
4198 | |
4199 | do { |
4200 | crWaitUntilV(ispkt); |
4201 | if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) { |
4202 | unsigned i = ssh2_pkt_getuint32(); |
4203 | struct ssh_channel *c; |
4204 | c = find234(ssh_channels, &i, ssh_channelfind); |
4205 | if (!c) |
4206 | continue; /* nonexistent channel */ |
4207 | c->v2.remwindow += ssh2_pkt_getuint32(); |
4208 | } |
4209 | } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST); |
4210 | |
4211 | if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) { |
4212 | if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) { |
4213 | bombout( |
4214 | ("Server got confused by agent forwarding request")); |
4215 | crReturnV; |
4216 | } |
4217 | logevent("Agent forwarding refused"); |
4218 | } else { |
4219 | logevent("Agent forwarding enabled"); |
36c2a3e9 |
4220 | ssh_agentfwd_enabled = TRUE; |
32874aea |
4221 | } |
36c2a3e9 |
4222 | } |
4223 | |
4224 | /* |
7cca0d81 |
4225 | * Now allocate a pty for the session. |
4226 | */ |
67779be7 |
4227 | if (!cfg.nopty) { |
32874aea |
4228 | ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST); |
4229 | ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */ |
4230 | ssh2_pkt_addstring("pty-req"); |
4231 | ssh2_pkt_addbool(1); /* want reply */ |
4232 | ssh2_pkt_addstring(cfg.termtype); |
4233 | ssh2_pkt_adduint32(cols); |
4234 | ssh2_pkt_adduint32(rows); |
4235 | ssh2_pkt_adduint32(0); /* pixel width */ |
4236 | ssh2_pkt_adduint32(0); /* pixel height */ |
4237 | ssh2_pkt_addstring_start(); |
4238 | ssh2_pkt_addstring_data("\0", 1); /* TTY_OP_END, no special options */ |
4239 | ssh2_pkt_send(); |
4240 | ssh_state = SSH_STATE_INTERMED; |
4241 | |
4242 | do { |
4243 | crWaitUntilV(ispkt); |
4244 | if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) { |
4245 | unsigned i = ssh2_pkt_getuint32(); |
4246 | struct ssh_channel *c; |
4247 | c = find234(ssh_channels, &i, ssh_channelfind); |
4248 | if (!c) |
4249 | continue; /* nonexistent channel */ |
4250 | c->v2.remwindow += ssh2_pkt_getuint32(); |
4251 | } |
4252 | } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST); |
4253 | |
4254 | if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) { |
4255 | if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) { |
4256 | bombout(("Server got confused by pty request")); |
4257 | crReturnV; |
4258 | } |
4259 | c_write_str("Server refused to allocate pty\r\n"); |
4260 | ssh_editing = ssh_echoing = 1; |
4261 | } else { |
4262 | logevent("Allocated pty"); |
4263 | } |
0965bee0 |
4264 | } else { |
32874aea |
4265 | ssh_editing = ssh_echoing = 1; |
7cca0d81 |
4266 | } |
4267 | |
4268 | /* |
67779be7 |
4269 | * Start a shell or a remote command. |
7cca0d81 |
4270 | */ |
4271 | ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST); |
32874aea |
4272 | ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */ |
4a8fc3c4 |
4273 | if (cfg.ssh_subsys) { |
32874aea |
4274 | ssh2_pkt_addstring("subsystem"); |
4275 | ssh2_pkt_addbool(1); /* want reply */ |
4276 | ssh2_pkt_addstring(cfg.remote_cmd_ptr); |
96621a84 |
4277 | } else if (*cfg.remote_cmd_ptr) { |
32874aea |
4278 | ssh2_pkt_addstring("exec"); |
4279 | ssh2_pkt_addbool(1); /* want reply */ |
4280 | ssh2_pkt_addstring(cfg.remote_cmd_ptr); |
67779be7 |
4281 | } else { |
32874aea |
4282 | ssh2_pkt_addstring("shell"); |
4283 | ssh2_pkt_addbool(1); /* want reply */ |
67779be7 |
4284 | } |
7cca0d81 |
4285 | ssh2_pkt_send(); |
d211621f |
4286 | do { |
32874aea |
4287 | crWaitUntilV(ispkt); |
4288 | if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) { |
4289 | unsigned i = ssh2_pkt_getuint32(); |
4290 | struct ssh_channel *c; |
4291 | c = find234(ssh_channels, &i, ssh_channelfind); |
4292 | if (!c) |
4293 | continue; /* nonexistent channel */ |
4294 | c->v2.remwindow += ssh2_pkt_getuint32(); |
4295 | } |
7cca0d81 |
4296 | } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST); |
4297 | if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) { |
32874aea |
4298 | if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) { |
4299 | bombout(("Server got confused by shell/command request")); |
4300 | crReturnV; |
4301 | } |
4302 | bombout(("Server refused to start a shell/command")); |
4303 | crReturnV; |
7cca0d81 |
4304 | } else { |
32874aea |
4305 | logevent("Started a shell/command"); |
7cca0d81 |
4306 | } |
4307 | |
6e48c3fe |
4308 | ssh_state = SSH_STATE_SESSION; |
4309 | if (size_needed) |
4310 | ssh_size(); |
3687d221 |
4311 | if (eof_needed) |
32874aea |
4312 | ssh_special(TS_EOF); |
6e48c3fe |
4313 | |
7cca0d81 |
4314 | /* |
4315 | * Transfer data! |
4316 | */ |
32874aea |
4317 | ldisc_send(NULL, 0); /* cause ldisc to notice changes */ |
8ccc75b0 |
4318 | ssh_send_ok = 1; |
7cca0d81 |
4319 | while (1) { |
32874aea |
4320 | static int try_send; |
e5574168 |
4321 | crReturnV; |
32874aea |
4322 | try_send = FALSE; |
7cca0d81 |
4323 | if (ispkt) { |
4324 | if (pktin.type == SSH2_MSG_CHANNEL_DATA || |
32874aea |
4325 | pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) { |
4326 | char *data; |
4327 | int length; |
4328 | unsigned i = ssh2_pkt_getuint32(); |
4329 | struct ssh_channel *c; |
4330 | c = find234(ssh_channels, &i, ssh_channelfind); |
4331 | if (!c) |
4332 | continue; /* nonexistent channel */ |
4333 | if (pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA && |
4334 | ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR) |
4335 | continue; /* extended but not stderr */ |
4336 | ssh2_pkt_getstring(&data, &length); |
4337 | if (data) { |
4338 | switch (c->type) { |
4339 | case CHAN_MAINSESSION: |
4340 | from_backend(pktin.type == |
4341 | SSH2_MSG_CHANNEL_EXTENDED_DATA, data, |
4342 | length); |
4343 | break; |
4344 | case CHAN_X11: |
4345 | x11_send(c->u.x11.s, data, length); |
4346 | break; |
d74d141c |
4347 | case CHAN_SOCKDATA: |
bc240b21 |
4348 | pfd_send(c->u.pfd.s, data, length); |
4349 | break; |
36c2a3e9 |
4350 | case CHAN_AGENT: |
32874aea |
4351 | while (length > 0) { |
4352 | if (c->u.a.lensofar < 4) { |
4353 | int l = min(4 - c->u.a.lensofar, length); |
4354 | memcpy(c->u.a.msglen + c->u.a.lensofar, |
4355 | data, l); |
4356 | data += l; |
4357 | length -= l; |
4358 | c->u.a.lensofar += l; |
4359 | } |
4360 | if (c->u.a.lensofar == 4) { |
4361 | c->u.a.totallen = |
4362 | 4 + GET_32BIT(c->u.a.msglen); |
4363 | c->u.a.message = smalloc(c->u.a.totallen); |
4364 | memcpy(c->u.a.message, c->u.a.msglen, 4); |
4365 | } |
4366 | if (c->u.a.lensofar >= 4 && length > 0) { |
4367 | int l = |
4368 | min(c->u.a.totallen - c->u.a.lensofar, |
4369 | length); |
4370 | memcpy(c->u.a.message + c->u.a.lensofar, |
4371 | data, l); |
4372 | data += l; |
4373 | length -= l; |
4374 | c->u.a.lensofar += l; |
4375 | } |
4376 | if (c->u.a.lensofar == c->u.a.totallen) { |
4377 | void *reply, *sentreply; |
4378 | int replylen; |
4379 | agent_query(c->u.a.message, |
4380 | c->u.a.totallen, &reply, |
4381 | &replylen); |
4382 | if (reply) |
4383 | sentreply = reply; |
4384 | else { |
4385 | /* Fake SSH_AGENT_FAILURE. */ |
4386 | sentreply = "\0\0\0\1\5"; |
4387 | replylen = 5; |
4388 | } |
4389 | ssh2_add_channel_data(c, sentreply, |
4390 | replylen); |
36c2a3e9 |
4391 | try_send = TRUE; |
32874aea |
4392 | if (reply) |
4393 | sfree(reply); |
4394 | sfree(c->u.a.message); |
4395 | c->u.a.lensofar = 0; |
4396 | } |
4397 | } |
4398 | break; |
4399 | } |
4400 | /* |
4401 | * Enlarge the window again at the remote |
4402 | * side, just in case it ever runs down and |
4403 | * they fail to send us any more data. |
4404 | */ |
4405 | ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST); |
4406 | ssh2_pkt_adduint32(c->remoteid); |
4407 | ssh2_pkt_adduint32(length); |
4408 | ssh2_pkt_send(); |
4409 | } |
7cca0d81 |
4410 | } else if (pktin.type == SSH2_MSG_DISCONNECT) { |
32874aea |
4411 | ssh_state = SSH_STATE_CLOSED; |
d211621f |
4412 | logevent("Received disconnect message"); |
32874aea |
4413 | crReturnV; |
7cca0d81 |
4414 | } else if (pktin.type == SSH2_MSG_CHANNEL_REQUEST) { |
32874aea |
4415 | continue; /* exit status et al; ignore (FIXME?) */ |
d211621f |
4416 | } else if (pktin.type == SSH2_MSG_CHANNEL_EOF) { |
32874aea |
4417 | unsigned i = ssh2_pkt_getuint32(); |
4418 | struct ssh_channel *c; |
4419 | |
4420 | c = find234(ssh_channels, &i, ssh_channelfind); |
4421 | if (!c) |
4422 | continue; /* nonexistent channel */ |
4423 | |
4424 | if (c->type == CHAN_X11) { |
4425 | /* |
4426 | * Remote EOF on an X11 channel means we should |
4427 | * wrap up and close the channel ourselves. |
4428 | */ |
4429 | x11_close(c->u.x11.s); |
4430 | sshfwd_close(c); |
4431 | } else if (c->type == CHAN_AGENT) { |
36c2a3e9 |
4432 | sshfwd_close(c); |
d74d141c |
4433 | } else if (c->type == CHAN_SOCKDATA) { |
bc240b21 |
4434 | pfd_close(c->u.pfd.s); |
4435 | sshfwd_close(c); |
36c2a3e9 |
4436 | } |
d211621f |
4437 | } else if (pktin.type == SSH2_MSG_CHANNEL_CLOSE) { |
32874aea |
4438 | unsigned i = ssh2_pkt_getuint32(); |
4439 | struct ssh_channel *c; |
4440 | |
4441 | c = find234(ssh_channels, &i, ssh_channelfind); |
4442 | if (!c) |
4443 | continue; /* nonexistent channel */ |
4444 | if (c->closes == 0) { |
4445 | ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE); |
4446 | ssh2_pkt_adduint32(c->remoteid); |
4447 | ssh2_pkt_send(); |
4448 | } |
4449 | /* Do pre-close processing on the channel. */ |
4450 | switch (c->type) { |
4451 | case CHAN_MAINSESSION: |
4452 | break; /* nothing to see here, move along */ |
4453 | case CHAN_X11: |
4454 | break; |
4455 | case CHAN_AGENT: |
4456 | break; |
d74d141c |
4457 | case CHAN_SOCKDATA: |
bc240b21 |
4458 | break; |
32874aea |
4459 | } |
4460 | del234(ssh_channels, c); |
4461 | sfree(c->v2.outbuffer); |
4462 | sfree(c); |
4463 | |
4464 | /* |
4465 | * See if that was the last channel left open. |
4466 | */ |
4467 | if (count234(ssh_channels) == 0) { |
4468 | logevent("All channels closed. Disconnecting"); |
4469 | ssh2_pkt_init(SSH2_MSG_DISCONNECT); |
4470 | ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION); |
4471 | ssh2_pkt_addstring("All open channels closed"); |
4472 | ssh2_pkt_addstring("en"); /* language tag */ |
4473 | ssh2_pkt_send(); |
4474 | ssh_state = SSH_STATE_CLOSED; |
4475 | crReturnV; |
4476 | } |
4477 | continue; /* remote sends close; ignore (FIXME) */ |
7cca0d81 |
4478 | } else if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) { |
32874aea |
4479 | unsigned i = ssh2_pkt_getuint32(); |
4480 | struct ssh_channel *c; |
4481 | c = find234(ssh_channels, &i, ssh_channelfind); |
4482 | if (!c) |
4483 | continue; /* nonexistent channel */ |
4484 | c->v2.remwindow += ssh2_pkt_getuint32(); |
4485 | try_send = TRUE; |
bc240b21 |
4486 | } else if (pktin.type == SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) { |
4487 | unsigned i = ssh2_pkt_getuint32(); |
4488 | struct ssh_channel *c; |
4489 | c = find234(ssh_channels, &i, ssh_channelfind); |
4490 | if (!c) |
4491 | continue; /* nonexistent channel */ |
4492 | if (c->type != CHAN_SOCKDATA_DORMANT) |
4493 | continue; /* dunno why they're confirming this */ |
4494 | c->remoteid = ssh2_pkt_getuint32(); |
4495 | c->type = CHAN_SOCKDATA; |
4496 | c->closes = 0; |
4497 | c->v2.remwindow = ssh2_pkt_getuint32(); |
4498 | c->v2.remmaxpkt = ssh2_pkt_getuint32(); |
4499 | c->v2.outbuffer = NULL; |
4500 | c->v2.outbuflen = c->v2.outbufsize = 0; |
4501 | pfd_confirm(c->u.pfd.s); |
783415f8 |
4502 | } else if (pktin.type == SSH2_MSG_CHANNEL_OPEN) { |
32874aea |
4503 | char *type; |
4504 | int typelen; |
4505 | char *error = NULL; |
4506 | struct ssh_channel *c; |
bc240b21 |
4507 | unsigned remid, winsize, pktsize; |
32874aea |
4508 | ssh2_pkt_getstring(&type, &typelen); |
4509 | c = smalloc(sizeof(struct ssh_channel)); |
4510 | |
bc240b21 |
4511 | remid = ssh2_pkt_getuint32(); |
4512 | winsize = ssh2_pkt_getuint32(); |
4513 | pktsize = ssh2_pkt_getuint32(); |
4514 | |
32874aea |
4515 | if (typelen == 3 && !memcmp(type, "x11", 3)) { |
4516 | if (!ssh_X11_fwd_enabled) |
4517 | error = "X11 forwarding is not enabled"; |
4518 | else if (x11_init(&c->u.x11.s, cfg.x11_display, c) != |
4519 | NULL) { |
4520 | error = "Unable to open an X11 connection"; |
4521 | } else { |
4522 | c->type = CHAN_X11; |
4523 | } |
bc240b21 |
4524 | } else if (typelen == 15 && |
4525 | !memcmp(type, "forwarded-tcpip", 15)) { |
4526 | struct ssh_rportfwd pf, *realpf; |
4527 | char *dummy; |
4528 | int dummylen; |
4529 | ssh2_pkt_getstring(&dummy, &dummylen);/* skip address */ |
4530 | pf.sport = ssh2_pkt_getuint32(); |
4531 | realpf = find234(ssh_rportfwds, &pf, NULL); |
4532 | if (realpf == NULL) { |
4533 | error = "Remote port is not recognised"; |
4534 | } else { |
4535 | char *e = pfd_newconnect(&c->u.pfd.s, realpf->dhost, |
4536 | realpf->dport, c); |
4537 | char buf[1024]; |
4538 | sprintf(buf, "Received remote port open request for %s:%d", |
4539 | realpf->dhost, realpf->dport); |
4540 | logevent(buf); |
4541 | if (e != NULL) { |
4542 | sprintf(buf, "Port open failed: %s", e); |
4543 | logevent(buf); |
4544 | error = "Port open failed"; |
4545 | } else { |
4546 | logevent("Forwarded port opened successfully"); |
4547 | c->type = CHAN_SOCKDATA; |
4548 | } |
4549 | } |
32874aea |
4550 | } else if (typelen == 22 && |
36c2a3e9 |
4551 | !memcmp(type, "auth-agent@openssh.com", 3)) { |
32874aea |
4552 | if (!ssh_agentfwd_enabled) |
4553 | error = "Agent forwarding is not enabled"; |
36c2a3e9 |
4554 | else { |
32874aea |
4555 | c->type = CHAN_AGENT; /* identify channel type */ |
36c2a3e9 |
4556 | c->u.a.lensofar = 0; |
32874aea |
4557 | } |
4558 | } else { |
4559 | error = "Unsupported channel type requested"; |
4560 | } |
4561 | |
bc240b21 |
4562 | c->remoteid = remid; |
32874aea |
4563 | if (error) { |
4564 | ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE); |
4565 | ssh2_pkt_adduint32(c->remoteid); |
4566 | ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED); |
4567 | ssh2_pkt_addstring(error); |
4568 | ssh2_pkt_addstring("en"); /* language tag */ |
4569 | ssh2_pkt_send(); |
4570 | sfree(c); |
4571 | } else { |
4572 | c->localid = alloc_channel_id(); |
4573 | c->closes = 0; |
bc240b21 |
4574 | c->v2.remwindow = winsize; |
4575 | c->v2.remmaxpkt = pktsize; |
32874aea |
4576 | c->v2.outbuffer = NULL; |
4577 | c->v2.outbuflen = c->v2.outbufsize = 0; |
4578 | add234(ssh_channels, c); |
4579 | ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); |
4580 | ssh2_pkt_adduint32(c->remoteid); |
4581 | ssh2_pkt_adduint32(c->localid); |
4582 | ssh2_pkt_adduint32(0x8000UL); /* our window size */ |
4583 | ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */ |
4584 | ssh2_pkt_send(); |
4585 | } |
7cca0d81 |
4586 | } else { |
8d5de777 |
4587 | bombout(("Strange packet received: type %d", pktin.type)); |
32874aea |
4588 | crReturnV; |
7cca0d81 |
4589 | } |
4590 | } else { |
32874aea |
4591 | /* |
4592 | * We have spare data. Add it to the channel buffer. |
4593 | */ |
4594 | ssh2_add_channel_data(mainchan, in, inlen); |
4595 | try_send = TRUE; |
4596 | } |
4597 | if (try_send) { |
4598 | int i; |
4599 | struct ssh_channel *c; |
4600 | /* |
4601 | * Try to send data on all channels if we can. |
4602 | */ |
4603 | for (i = 0; NULL != (c = index234(ssh_channels, i)); i++) |
4604 | ssh2_try_send(c); |
7cca0d81 |
4605 | } |
e5574168 |
4606 | } |
4607 | |
4608 | crFinishV; |
4609 | } |
4610 | |
4611 | /* |
7cca0d81 |
4612 | * Handle the top-level SSH2 protocol. |
4613 | */ |
4614 | static void ssh2_protocol(unsigned char *in, int inlen, int ispkt) |
4615 | { |
4616 | if (do_ssh2_transport(in, inlen, ispkt) == 0) |
32874aea |
4617 | return; |
7cca0d81 |
4618 | do_ssh2_authconn(in, inlen, ispkt); |
4619 | } |
4620 | |
4621 | /* |
8df7a775 |
4622 | * Called to set up the connection. |
374330e2 |
4623 | * |
4624 | * Returns an error message, or NULL on success. |
374330e2 |
4625 | */ |
32874aea |
4626 | static char *ssh_init(char *host, int port, char **realhost) |
4627 | { |
fb09bf1c |
4628 | char *p; |
32874aea |
4629 | |
8f203108 |
4630 | #ifdef MSCRYPTOAPI |
32874aea |
4631 | if (crypto_startup() == 0) |
8f203108 |
4632 | return "Microsoft high encryption pack not installed!"; |
4633 | #endif |
374330e2 |
4634 | |
8df7a775 |
4635 | ssh_send_ok = 0; |
0965bee0 |
4636 | ssh_editing = 0; |
4637 | ssh_echoing = 0; |
8df7a775 |
4638 | |
fb09bf1c |
4639 | p = connect_to_host(host, port, realhost); |
4640 | if (p != NULL) |
4641 | return p; |
374330e2 |
4642 | |
374330e2 |
4643 | return NULL; |
4644 | } |
4645 | |
4646 | /* |
374330e2 |
4647 | * Called to send data down the Telnet connection. |
4648 | */ |
32874aea |
4649 | static void ssh_send(char *buf, int len) |
4650 | { |
f78051a1 |
4651 | if (s == NULL || ssh_protocol == NULL) |
374330e2 |
4652 | return; |
4653 | |
4654 | ssh_protocol(buf, len, 0); |
4655 | } |
4656 | |
4657 | /* |
6e48c3fe |
4658 | * Called to set the size of the window from SSH's POV. |
374330e2 |
4659 | */ |
32874aea |
4660 | static void ssh_size(void) |
4661 | { |
374330e2 |
4662 | switch (ssh_state) { |
4663 | case SSH_STATE_BEFORE_SIZE: |
3687d221 |
4664 | case SSH_STATE_PREPACKET: |
21248260 |
4665 | case SSH_STATE_CLOSED: |
374330e2 |
4666 | break; /* do nothing */ |
4667 | case SSH_STATE_INTERMED: |
4668 | size_needed = TRUE; /* buffer for later */ |
4669 | break; |
4670 | case SSH_STATE_SESSION: |
32874aea |
4671 | if (!cfg.nopty) { |
4672 | if (ssh_version == 1) { |
4673 | send_packet(SSH1_CMSG_WINDOW_SIZE, |
4674 | PKT_INT, rows, PKT_INT, cols, |
4675 | PKT_INT, 0, PKT_INT, 0, PKT_END); |
4676 | } else { |
4677 | ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST); |
4678 | ssh2_pkt_adduint32(mainchan->remoteid); |
4679 | ssh2_pkt_addstring("window-change"); |
4680 | ssh2_pkt_addbool(0); |
4681 | ssh2_pkt_adduint32(cols); |
4682 | ssh2_pkt_adduint32(rows); |
4683 | ssh2_pkt_adduint32(0); |
4684 | ssh2_pkt_adduint32(0); |
4685 | ssh2_pkt_send(); |
4686 | } |
4687 | } |
4688 | break; |
374330e2 |
4689 | } |
4690 | } |
4691 | |
4692 | /* |
6abbf9e3 |
4693 | * Send Telnet special codes. TS_EOF is useful for `plink', so you |
4694 | * can send an EOF and collect resulting output (e.g. `plink |
4695 | * hostname sort'). |
374330e2 |
4696 | */ |
32874aea |
4697 | static void ssh_special(Telnet_Special code) |
4698 | { |
6abbf9e3 |
4699 | if (code == TS_EOF) { |
32874aea |
4700 | if (ssh_state != SSH_STATE_SESSION) { |
4701 | /* |
4702 | * Buffer the EOF in case we are pre-SESSION, so we can |
4703 | * send it as soon as we reach SESSION. |
4704 | */ |
4705 | if (code == TS_EOF) |
4706 | eof_needed = TRUE; |
4707 | return; |
4708 | } |
4709 | if (ssh_version == 1) { |
4710 | send_packet(SSH1_CMSG_EOF, PKT_END); |
4711 | } else { |
4712 | ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF); |
4713 | ssh2_pkt_adduint32(mainchan->remoteid); |
4714 | ssh2_pkt_send(); |
4715 | } |
4716 | logevent("Sent EOF message"); |
ec55b220 |
4717 | } else if (code == TS_PING) { |
32874aea |
4718 | if (ssh_state == SSH_STATE_CLOSED |
4719 | || ssh_state == SSH_STATE_PREPACKET) return; |
4720 | if (ssh_version == 1) { |
4721 | send_packet(SSH1_MSG_IGNORE, PKT_STR, "", PKT_END); |
4722 | } else { |
4723 | ssh2_pkt_init(SSH2_MSG_IGNORE); |
4724 | ssh2_pkt_addstring_start(); |
4725 | ssh2_pkt_send(); |
4726 | } |
6abbf9e3 |
4727 | } else { |
32874aea |
4728 | /* do nothing */ |
6abbf9e3 |
4729 | } |
374330e2 |
4730 | } |
4731 | |
d74d141c |
4732 | void *new_sock_channel(Socket s) |
4733 | { |
4734 | struct ssh_channel *c; |
4735 | c = smalloc(sizeof(struct ssh_channel)); |
4736 | |
4737 | if (c) { |
bc240b21 |
4738 | c->remoteid = -1; /* to be set when open confirmed */ |
d74d141c |
4739 | c->localid = alloc_channel_id(); |
4740 | c->closes = 0; |
bc240b21 |
4741 | c->type = CHAN_SOCKDATA_DORMANT;/* identify channel type */ |
d74d141c |
4742 | c->u.pfd.s = s; |
4743 | add234(ssh_channels, c); |
4744 | } |
4745 | return c; |
4746 | } |
4747 | |
4748 | void ssh_send_port_open(void *channel, char *hostname, int port, char *org) |
4749 | { |
4750 | struct ssh_channel *c = (struct ssh_channel *)channel; |
4751 | char buf[1024]; |
4752 | |
4753 | sprintf(buf, "Opening forwarded connection to %.512s:%d", hostname, port); |
4754 | logevent(buf); |
4755 | |
bc240b21 |
4756 | if (ssh_version == 1) { |
4757 | send_packet(SSH1_MSG_PORT_OPEN, |
4758 | PKT_INT, c->localid, |
4759 | PKT_STR, hostname, |
4760 | PKT_INT, port, |
4761 | //PKT_STR, <org:orgport>, |
4762 | PKT_END); |
4763 | } else { |
4764 | ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN); |
4765 | ssh2_pkt_addstring("direct-tcpip"); |
4766 | ssh2_pkt_adduint32(c->localid); |
4767 | ssh2_pkt_adduint32(0x8000UL); /* our window size */ |
4768 | ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */ |
4769 | ssh2_pkt_addstring(hostname); |
4770 | ssh2_pkt_adduint32(port); |
4771 | /* |
4772 | * We make up values for the originator data; partly it's |
4773 | * too much hassle to keep track, and partly I'm not |
4774 | * convinced the server should be told details like that |
4775 | * about my local network configuration. |
4776 | */ |
4777 | ssh2_pkt_addstring("client-side-connection"); |
4778 | ssh2_pkt_adduint32(0); |
4779 | ssh2_pkt_send(); |
4780 | } |
d74d141c |
4781 | } |
4782 | |
4783 | |
32874aea |
4784 | static Socket ssh_socket(void) |
4785 | { |
4786 | return s; |
4787 | } |
8ccc75b0 |
4788 | |
32874aea |
4789 | static int ssh_sendok(void) |
4790 | { |
4791 | return ssh_send_ok; |
4792 | } |
fb09bf1c |
4793 | |
32874aea |
4794 | static int ssh_ldisc(int option) |
4795 | { |
4796 | if (option == LD_ECHO) |
4797 | return ssh_echoing; |
4798 | if (option == LD_EDIT) |
4799 | return ssh_editing; |
0965bee0 |
4800 | return FALSE; |
4801 | } |
4802 | |
374330e2 |
4803 | Backend ssh_backend = { |
4804 | ssh_init, |
374330e2 |
4805 | ssh_send, |
4806 | ssh_size, |
4017be6d |
4807 | ssh_special, |
8ccc75b0 |
4808 | ssh_socket, |
97db3be4 |
4809 | ssh_sendok, |
0965bee0 |
4810 | ssh_ldisc, |
97db3be4 |
4811 | 22 |
bc240b21 |
4812 | }; |