X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/5c58ad2d1527936b4d30891497eef48bde0fe1f3..2c94fd1cbf32093be173ea6c4378caa109f73dd4:/ssh.c diff --git a/ssh.c b/ssh.c index dd8ffd57..3845264c 100644 --- a/ssh.c +++ b/ssh.c @@ -1,12 +1,12 @@ +#include #include #include #include #include -#include #include "putty.h" +#include "tree234.h" #include "ssh.h" -#include "scp.h" #ifndef FALSE #define FALSE 0 @@ -16,86 +16,115 @@ #endif #define logevent(s) { logevent(s); \ - if (!(flags & FLAG_CONNECTION) && (flags & FLAG_VERBOSE)) \ + if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) \ fprintf(stderr, "%s\n", s); } -#define SSH1_MSG_DISCONNECT 1 -#define SSH1_SMSG_PUBLIC_KEY 2 -#define SSH1_CMSG_SESSION_KEY 3 -#define SSH1_CMSG_USER 4 -#define SSH1_CMSG_AUTH_RSA 6 -#define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 -#define SSH1_CMSG_AUTH_RSA_RESPONSE 8 -#define SSH1_CMSG_AUTH_PASSWORD 9 -#define SSH1_CMSG_REQUEST_PTY 10 -#define SSH1_CMSG_WINDOW_SIZE 11 -#define SSH1_CMSG_EXEC_SHELL 12 -#define SSH1_CMSG_EXEC_CMD 13 -#define SSH1_SMSG_SUCCESS 14 -#define SSH1_SMSG_FAILURE 15 -#define SSH1_CMSG_STDIN_DATA 16 -#define SSH1_SMSG_STDOUT_DATA 17 -#define SSH1_SMSG_STDERR_DATA 18 -#define SSH1_CMSG_EOF 19 -#define SSH1_SMSG_EXIT_STATUS 20 -#define SSH1_CMSG_EXIT_CONFIRMATION 33 -#define SSH1_MSG_IGNORE 32 -#define SSH1_MSG_DEBUG 36 -#define SSH1_CMSG_AUTH_TIS 39 -#define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 -#define SSH1_CMSG_AUTH_TIS_RESPONSE 41 -#define SSH1_CMSG_AUTH_CCARD 70 -#define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 -#define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 - -#define SSH1_AUTH_TIS 5 -#define SSH1_AUTH_CCARD 16 - -#define SSH_AGENTC_REQUEST_RSA_IDENTITIES 1 -#define SSH_AGENT_RSA_IDENTITIES_ANSWER 2 -#define SSH_AGENTC_RSA_CHALLENGE 3 -#define SSH_AGENT_RSA_RESPONSE 4 -#define SSH_AGENT_FAILURE 5 -#define SSH_AGENT_SUCCESS 6 -#define SSH_AGENTC_ADD_RSA_IDENTITY 7 -#define SSH_AGENTC_REMOVE_RSA_IDENTITY 8 - -#define SSH2_MSG_DISCONNECT 1 -#define SSH2_MSG_IGNORE 2 -#define SSH2_MSG_UNIMPLEMENTED 3 -#define SSH2_MSG_DEBUG 4 -#define SSH2_MSG_SERVICE_REQUEST 5 -#define SSH2_MSG_SERVICE_ACCEPT 6 -#define SSH2_MSG_KEXINIT 20 -#define SSH2_MSG_NEWKEYS 21 -#define SSH2_MSG_KEXDH_INIT 30 -#define SSH2_MSG_KEXDH_REPLY 31 -#define SSH2_MSG_USERAUTH_REQUEST 50 -#define SSH2_MSG_USERAUTH_FAILURE 51 -#define SSH2_MSG_USERAUTH_SUCCESS 52 -#define SSH2_MSG_USERAUTH_BANNER 53 -#define SSH2_MSG_USERAUTH_PK_OK 60 -#define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 -#define SSH2_MSG_GLOBAL_REQUEST 80 -#define SSH2_MSG_REQUEST_SUCCESS 81 -#define SSH2_MSG_REQUEST_FAILURE 82 -#define SSH2_MSG_CHANNEL_OPEN 90 -#define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 -#define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 -#define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 -#define SSH2_MSG_CHANNEL_DATA 94 -#define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 -#define SSH2_MSG_CHANNEL_EOF 96 -#define SSH2_MSG_CHANNEL_CLOSE 97 -#define SSH2_MSG_CHANNEL_REQUEST 98 -#define SSH2_MSG_CHANNEL_SUCCESS 99 -#define SSH2_MSG_CHANNEL_FAILURE 100 - -#define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 -#define SSH2_OPEN_CONNECT_FAILED 2 -#define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 -#define SSH2_OPEN_RESOURCE_SHORTAGE 4 -#define SSH2_EXTENDED_DATA_STDERR 1 +#define bombout(msg) ( ssh_state = SSH_STATE_CLOSED, sk_close(s), \ + s = NULL, connection_fatal msg ) + +#define SSH1_MSG_DISCONNECT 1 /* 0x1 */ +#define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */ +#define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */ +#define SSH1_CMSG_USER 4 /* 0x4 */ +#define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */ +#define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */ +#define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */ +#define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */ +#define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */ +#define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */ +#define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */ +#define SSH1_CMSG_EXEC_CMD 13 /* 0xd */ +#define SSH1_SMSG_SUCCESS 14 /* 0xe */ +#define SSH1_SMSG_FAILURE 15 /* 0xf */ +#define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */ +#define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */ +#define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */ +#define SSH1_CMSG_EOF 19 /* 0x13 */ +#define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */ +#define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */ +#define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */ +#define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */ +#define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */ +#define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */ +#define SSH1_SMSG_X11_OPEN 27 /* 0x1b */ +#define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */ +#define SSH1_MSG_PORT_OPEN 29 /* 0x1d */ +#define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */ +#define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */ +#define SSH1_MSG_IGNORE 32 /* 0x20 */ +#define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */ +#define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */ +#define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */ +#define SSH1_MSG_DEBUG 36 /* 0x24 */ +#define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */ +#define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */ +#define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */ +#define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */ +#define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */ +#define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */ +#define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */ + +#define SSH1_AUTH_TIS 5 /* 0x5 */ +#define SSH1_AUTH_CCARD 16 /* 0x10 */ + +#define SSH_AGENTC_REQUEST_RSA_IDENTITIES 1 /* 0x1 */ +#define SSH_AGENT_RSA_IDENTITIES_ANSWER 2 /* 0x2 */ +#define SSH_AGENTC_RSA_CHALLENGE 3 /* 0x3 */ +#define SSH_AGENT_RSA_RESPONSE 4 /* 0x4 */ +#define SSH_AGENT_FAILURE 5 /* 0x5 */ +#define SSH_AGENT_SUCCESS 6 /* 0x6 */ +#define SSH_AGENTC_ADD_RSA_IDENTITY 7 /* 0x7 */ +#define SSH_AGENTC_REMOVE_RSA_IDENTITY 8 /* 0x8 */ + +#define SSH2_MSG_DISCONNECT 1 /* 0x1 */ +#define SSH2_MSG_IGNORE 2 /* 0x2 */ +#define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */ +#define SSH2_MSG_DEBUG 4 /* 0x4 */ +#define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */ +#define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */ +#define SSH2_MSG_KEXINIT 20 /* 0x14 */ +#define SSH2_MSG_NEWKEYS 21 /* 0x15 */ +#define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */ +#define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */ +#define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */ +#define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */ +#define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */ +#define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */ +#define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */ +#define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */ +#define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */ +#define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */ +#define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */ +#define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */ +#define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */ +#define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */ +#define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */ +#define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */ +#define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */ +#define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */ +#define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */ +#define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */ +#define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */ +#define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */ + +#define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */ +#define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */ +#define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */ +#define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */ +#define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */ +#define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */ +#define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */ +#define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */ +#define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */ +#define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */ +#define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */ + +#define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */ +#define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */ +#define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */ +#define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */ + +#define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */ #define GET_32BIT(cp) \ (((unsigned long)(unsigned char)(cp)[0] << 24) | \ @@ -130,119 +159,188 @@ enum { PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM }; #define crWaitUntil(c) do { crReturn(0); } while (!(c)) #define crWaitUntilV(c) do { crReturnV; } while (!(c)) -extern struct ssh_cipher ssh_3des; -extern struct ssh_cipher ssh_3des_ssh2; -extern struct ssh_cipher ssh_des; -extern struct ssh_cipher ssh_blowfish; +extern const struct ssh_cipher ssh_3des; +extern const struct ssh_cipher ssh_3des_ssh2; +extern const struct ssh_cipher ssh_des; +extern const struct ssh_cipher ssh_blowfish_ssh1; +extern const struct ssh_cipher ssh_blowfish_ssh2; -/* for ssh 2; we miss out single-DES because it isn't supported */ -struct ssh_cipher *ciphers[] = { &ssh_3des_ssh2, &ssh_blowfish }; +extern char *x11_init (Socket *, char *, void *); +extern void x11_close (Socket); +extern void x11_send (Socket , char *, int); +extern void x11_invent_auth(char *, int, char *, int); -extern struct ssh_kex ssh_diffiehellman; -struct ssh_kex *kex_algs[] = { &ssh_diffiehellman }; +/* + * Ciphers for SSH2. We miss out single-DES because it isn't + * supported; also 3DES and Blowfish are both done differently from + * SSH1. (3DES uses outer chaining; Blowfish has the opposite + * endianness and different-sized keys.) + */ +const static struct ssh_cipher *ciphers[] = { &ssh_blowfish_ssh2, &ssh_3des_ssh2 }; -extern struct ssh_hostkey ssh_dss; -struct ssh_hostkey *hostkey_algs[] = { &ssh_dss }; +extern const struct ssh_kex ssh_diffiehellman; +const static struct ssh_kex *kex_algs[] = { &ssh_diffiehellman }; -extern struct ssh_mac ssh_sha1; +extern const struct ssh_signkey ssh_dss; +const static struct ssh_signkey *hostkey_algs[] = { &ssh_dss }; -SHA_State exhash; +extern const struct ssh_mac ssh_md5, ssh_sha1, ssh_sha1_buggy; static void nullmac_key(unsigned char *key) { } static void nullmac_generate(unsigned char *blk, int len, unsigned long seq) { } static int nullmac_verify(unsigned char *blk, int len, unsigned long seq) { return 1; } -struct ssh_mac ssh_mac_none = { +const static struct ssh_mac ssh_mac_none = { nullmac_key, nullmac_key, nullmac_generate, nullmac_verify, "none", 0 }; -struct ssh_mac *macs[] = { &ssh_sha1, &ssh_mac_none }; +const static struct ssh_mac *macs[] = { + &ssh_sha1, &ssh_md5, &ssh_mac_none }; +const static struct ssh_mac *buggymacs[] = { + &ssh_sha1_buggy, &ssh_md5, &ssh_mac_none }; + +static void ssh_comp_none_init(void) { } +static int ssh_comp_none_block(unsigned char *block, int len, + unsigned char **outblock, int *outlen) { + return 0; +} +const static struct ssh_compress ssh_comp_none = { + "none", + ssh_comp_none_init, ssh_comp_none_block, + ssh_comp_none_init, ssh_comp_none_block +}; +extern const struct ssh_compress ssh_zlib; +const static struct ssh_compress *compressions[] = { + &ssh_zlib, &ssh_comp_none }; + +enum { /* channel types */ + CHAN_MAINSESSION, + CHAN_X11, + CHAN_AGENT, +}; + +/* + * 2-3-4 tree storing channels. + */ +struct ssh_channel { + unsigned remoteid, localid; + int type; + int closes; + struct ssh2_data_channel { + unsigned char *outbuffer; + unsigned outbuflen, outbufsize; + unsigned remwindow, remmaxpkt; + } v2; + union { + struct ssh_agent_channel { + unsigned char *message; + unsigned char msglen[4]; + int lensofar, totallen; + } a; + struct ssh_x11_channel { + Socket s; + } x11; + } u; +}; -struct ssh_compress ssh_comp_none = { - "none" +struct Packet { + long length; + int type; + unsigned char *data; + unsigned char *body; + long savedpos; + long maxlen; }; -struct ssh_compress *compressions[] = { &ssh_comp_none }; -static SOCKET s = INVALID_SOCKET; +static SHA_State exhash, exhashbase; + +static Socket s = NULL; static unsigned char session_key[32]; -static struct ssh_cipher *cipher = NULL; -static struct ssh_cipher *cscipher = NULL; -static struct ssh_cipher *sccipher = NULL; -static struct ssh_mac *csmac = NULL; -static struct ssh_mac *scmac = NULL; -static struct ssh_compress *cscomp = NULL; -static struct ssh_compress *sccomp = NULL; -static struct ssh_kex *kex = NULL; -static struct ssh_hostkey *hostkey = NULL; +static int ssh1_compressing; +static int ssh_agentfwd_enabled; +static int ssh_X11_fwd_enabled; +static const struct ssh_cipher *cipher = NULL; +static const struct ssh_cipher *cscipher = NULL; +static const struct ssh_cipher *sccipher = NULL; +static const struct ssh_mac *csmac = NULL; +static const struct ssh_mac *scmac = NULL; +static const struct ssh_compress *cscomp = NULL; +static const struct ssh_compress *sccomp = NULL; +static const struct ssh_kex *kex = NULL; +static const struct ssh_signkey *hostkey = NULL; int (*ssh_get_password)(const char *prompt, char *str, int maxlen) = NULL; static char *savedhost; +static int savedport; static int ssh_send_ok; +static tree234 *ssh_channels; /* indexed by local id */ +static struct ssh_channel *mainchan; /* primary session channel */ + static enum { + SSH_STATE_PREPACKET, SSH_STATE_BEFORE_SIZE, SSH_STATE_INTERMED, SSH_STATE_SESSION, SSH_STATE_CLOSED -} ssh_state = SSH_STATE_BEFORE_SIZE; +} ssh_state = SSH_STATE_PREPACKET; -static int size_needed = FALSE; +static int size_needed = FALSE, eof_needed = FALSE; -static void s_write (char *buf, int len) { - while (len > 0) { - int i = send (s, buf, len, 0); - noise_ultralight(i); - if (i <= 0) - fatalbox("Lost connection while sending"); - if (i > 0) - len -= i, buf += i; - } -} +static struct Packet pktin = { 0, 0, NULL, NULL, 0 }; +static struct Packet pktout = { 0, 0, NULL, NULL, 0 }; + +static int ssh_version; +static void (*ssh_protocol)(unsigned char *in, int inlen, int ispkt); +static void ssh1_protocol(unsigned char *in, int inlen, int ispkt); +static void ssh2_protocol(unsigned char *in, int inlen, int ispkt); +static void ssh_size(void); +static void ssh_special (Telnet_Special); +static void ssh2_try_send(struct ssh_channel *c); +static void ssh2_add_channel_data(struct ssh_channel *c, char *buf, int len); -static int s_read (char *buf, int len) { - int ret = 0; - while (len > 0) { - int i = recv (s, buf, len, 0); - noise_ultralight(i); - if (i > 0) - len -= i, buf += i, ret += i; - else - return i; - } - return ret; +static int (*s_rdpkt)(unsigned char **data, int *datalen); + +static struct rdpkt1_state_tag { + long len, pad, biglen, to_read; + unsigned long realcrc, gotcrc; + unsigned char *p; + int i; + int chunk; +} rdpkt1_state; + +static struct rdpkt2_state_tag { + long len, pad, payload, packetlen, maclen; + int i; + int cipherblk; + unsigned long incoming_sequence; +} rdpkt2_state; + +static int ssh_channelcmp(void *av, void *bv) { + struct ssh_channel *a = (struct ssh_channel *)av; + struct ssh_channel *b = (struct ssh_channel *)bv; + if (a->localid < b->localid) return -1; + if (a->localid > b->localid) return +1; + return 0; +} +static int ssh_channelfind(void *av, void *bv) { + unsigned *a = (unsigned *)av; + struct ssh_channel *b = (struct ssh_channel *)bv; + if (*a < b->localid) return -1; + if (*a > b->localid) return +1; + return 0; } static void c_write (char *buf, int len) { - if (!(flags & FLAG_CONNECTION)) { + if ((flags & FLAG_STDERR)) { int i; for (i = 0; i < len; i++) if (buf[i] != '\r') fputc(buf[i], stderr); return; } - while (len--) - c_write1(*buf++); + from_backend(1, buf, len); } -struct Packet { - long length; - int type; - unsigned char *data; - unsigned char *body; - long savedpos; - long maxlen; -}; - -static struct Packet pktin = { 0, 0, NULL, NULL, 0 }; -static struct Packet pktout = { 0, 0, NULL, NULL, 0 }; - -static int ssh_version; -static void (*ssh_protocol)(unsigned char *in, int inlen, int ispkt); -static void ssh1_protocol(unsigned char *in, int inlen, int ispkt); -static void ssh2_protocol(unsigned char *in, int inlen, int ispkt); -static void ssh_size(void); - -static int (*s_rdpkt)(unsigned char **data, int *datalen); - /* * Collect incoming data in the incoming packet buffer. * Decipher and verify the packet when it is completely read. @@ -253,10 +351,7 @@ static int (*s_rdpkt)(unsigned char **data, int *datalen); */ static int ssh1_rdpkt(unsigned char **data, int *datalen) { - static long len, pad, biglen, to_read; - static unsigned long realcrc, gotcrc; - static unsigned char *p; - static int i; + struct rdpkt1_state_tag *st = &rdpkt1_state; crBegin; @@ -265,57 +360,94 @@ next_packet: pktin.type = 0; pktin.length = 0; - for (i = len = 0; i < 4; i++) { + for (st->i = st->len = 0; st->i < 4; st->i++) { while ((*datalen) == 0) - crReturn(4-i); - len = (len << 8) + **data; + crReturn(4-st->i); + st->len = (st->len << 8) + **data; (*data)++, (*datalen)--; } #ifdef FWHACK - if (len == 0x52656d6f) { /* "Remo"te server has closed ... */ - len = 0x300; /* big enough to carry to end */ + if (st->len == 0x52656d6f) { /* "Remo"te server has closed ... */ + st->len = 0x300; /* big enough to carry to end */ } #endif - pad = 8 - (len % 8); - biglen = len + pad; - pktin.length = len - 5; + st->pad = 8 - (st->len % 8); + st->biglen = st->len + st->pad; + pktin.length = st->len - 5; - if (pktin.maxlen < biglen) { - pktin.maxlen = biglen; - pktin.data = (pktin.data == NULL ? malloc(biglen+APIEXTRA) : - realloc(pktin.data, biglen+APIEXTRA)); + if (pktin.maxlen < st->biglen) { + pktin.maxlen = st->biglen; + pktin.data = (pktin.data == NULL ? smalloc(st->biglen+APIEXTRA) : + srealloc(pktin.data, st->biglen+APIEXTRA)); if (!pktin.data) fatalbox("Out of memory"); } - to_read = biglen; - p = pktin.data; - while (to_read > 0) { - static int chunk; - chunk = to_read; + st->to_read = st->biglen; + st->p = pktin.data; + while (st->to_read > 0) { + st->chunk = st->to_read; while ((*datalen) == 0) - crReturn(to_read); - if (chunk > (*datalen)) - chunk = (*datalen); - memcpy(p, *data, chunk); - *data += chunk; - *datalen -= chunk; - p += chunk; - to_read -= chunk; + crReturn(st->to_read); + if (st->chunk > (*datalen)) + st->chunk = (*datalen); + memcpy(st->p, *data, st->chunk); + *data += st->chunk; + *datalen -= st->chunk; + st->p += st->chunk; + st->to_read -= st->chunk; } if (cipher) - cipher->decrypt(pktin.data, biglen); + cipher->decrypt(pktin.data, st->biglen); +#if 0 + debug(("Got packet len=%d pad=%d\r\n", st->len, st->pad)); + for (st->i = 0; st->i < st->biglen; st->i++) + debug((" %02x", (unsigned char)pktin.data[st->i])); + debug(("\r\n")); +#endif + + st->realcrc = crc32(pktin.data, st->biglen-4); + st->gotcrc = GET_32BIT(pktin.data+st->biglen-4); + if (st->gotcrc != st->realcrc) { + bombout(("Incorrect CRC received on packet")); + crReturn(0); + } - pktin.type = pktin.data[pad]; - pktin.body = pktin.data + pad + 1; + pktin.body = pktin.data + st->pad + 1; - realcrc = crc32(pktin.data, biglen-4); - gotcrc = GET_32BIT(pktin.data+biglen-4); - if (gotcrc != realcrc) { - fatalbox("Incorrect CRC received on packet"); + if (ssh1_compressing) { + unsigned char *decompblk; + int decomplen; +#if 0 + int i; + debug(("Packet payload pre-decompression:\n")); + for (i = -1; i < pktin.length; i++) + debug((" %02x", (unsigned char)pktin.body[i])); + debug(("\r\n")); +#endif + zlib_decompress_block(pktin.body-1, pktin.length+1, + &decompblk, &decomplen); + + if (pktin.maxlen < st->pad + decomplen) { + pktin.maxlen = st->pad + decomplen; + pktin.data = srealloc(pktin.data, pktin.maxlen+APIEXTRA); + pktin.body = pktin.data + st->pad + 1; + if (!pktin.data) + fatalbox("Out of memory"); + } + + memcpy(pktin.body-1, decompblk, decomplen); + sfree(decompblk); + pktin.length = decomplen-1; +#if 0 + debug(("Packet payload post-decompression:\n")); + for (i = -1; i < pktin.length; i++) + debug((" %02x", (unsigned char)pktin.body[i])); + debug(("\r\n")); +#endif } if (pktin.type == SSH1_SMSG_STDOUT_DATA || @@ -324,10 +456,14 @@ next_packet: pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE || pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) { long strlen = GET_32BIT(pktin.body); - if (strlen + 4 != pktin.length) - fatalbox("Received data packet with bogus string length"); + if (strlen + 4 != pktin.length) { + bombout(("Received data packet with bogus string length")); + crReturn(0); + } } + pktin.type = pktin.body[-1]; + if (pktin.type == SSH1_MSG_DEBUG) { /* log debug message */ char buf[80]; @@ -348,29 +484,24 @@ next_packet: static int ssh2_rdpkt(unsigned char **data, int *datalen) { - static long len, pad, payload, packetlen, maclen; - static int i; - static int cipherblk; - static unsigned long incoming_sequence = 0; + struct rdpkt2_state_tag *st = &rdpkt2_state; crBegin; next_packet: - pktin.type = 0; pktin.length = 0; - - if (cipher) - cipherblk = cipher->blksize; + if (sccipher) + st->cipherblk = sccipher->blksize; else - cipherblk = 8; - if (cipherblk < 8) - cipherblk = 8; - - if (pktin.maxlen < cipherblk) { - pktin.maxlen = cipherblk; - pktin.data = (pktin.data == NULL ? malloc(cipherblk+APIEXTRA) : - realloc(pktin.data, cipherblk+APIEXTRA)); + st->cipherblk = 8; + if (st->cipherblk < 8) + st->cipherblk = 8; + + if (pktin.maxlen < st->cipherblk) { + pktin.maxlen = st->cipherblk; + pktin.data = (pktin.data == NULL ? smalloc(st->cipherblk+APIEXTRA) : + srealloc(pktin.data, st->cipherblk+APIEXTRA)); if (!pktin.data) fatalbox("Out of memory"); } @@ -379,10 +510,10 @@ next_packet: * Acquire and decrypt the first block of the packet. This will * contain the length and padding details. */ - for (i = len = 0; i < cipherblk; i++) { + for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) { while ((*datalen) == 0) - crReturn(cipherblk-i); - pktin.data[i] = *(*data)++; + crReturn(st->cipherblk-st->i); + pktin.data[st->i] = *(*data)++; (*datalen)--; } #ifdef FWHACK @@ -391,34 +522,34 @@ next_packet: } #endif if (sccipher) - sccipher->decrypt(pktin.data, cipherblk); + sccipher->decrypt(pktin.data, st->cipherblk); /* * Now get the length and padding figures. */ - len = GET_32BIT(pktin.data); - pad = pktin.data[4]; + st->len = GET_32BIT(pktin.data); + st->pad = pktin.data[4]; /* * This enables us to deduce the payload length. */ - payload = len - pad - 1; + st->payload = st->len - st->pad - 1; - pktin.length = payload + 5; + pktin.length = st->payload + 5; /* * So now we can work out the total packet length. */ - packetlen = len + 4; - maclen = scmac ? scmac->len : 0; + st->packetlen = st->len + 4; + st->maclen = scmac ? scmac->len : 0; /* * Adjust memory allocation if packet is too big. */ - if (pktin.maxlen < packetlen) { - pktin.maxlen = packetlen; - pktin.data = (pktin.data == NULL ? malloc(packetlen+APIEXTRA) : - realloc(pktin.data, packetlen+APIEXTRA)); + if (pktin.maxlen < st->packetlen+st->maclen) { + pktin.maxlen = st->packetlen+st->maclen; + pktin.data = (pktin.data == NULL ? smalloc(pktin.maxlen+APIEXTRA) : + srealloc(pktin.data, pktin.maxlen+APIEXTRA)); if (!pktin.data) fatalbox("Out of memory"); } @@ -426,29 +557,60 @@ next_packet: /* * Read and decrypt the remainder of the packet. */ - for (i = cipherblk; i < packetlen + maclen; i++) { + for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen; st->i++) { while ((*datalen) == 0) - crReturn(packetlen + maclen - i); - pktin.data[i] = *(*data)++; + crReturn(st->packetlen + st->maclen - st->i); + pktin.data[st->i] = *(*data)++; (*datalen)--; } /* Decrypt everything _except_ the MAC. */ if (sccipher) - sccipher->decrypt(pktin.data + cipherblk, packetlen - cipherblk); + sccipher->decrypt(pktin.data + st->cipherblk, + st->packetlen - st->cipherblk); #if 0 - debug(("Got packet len=%d pad=%d\r\n", len, pad)); - for (i = 0; i < packetlen; i++) - debug((" %02x", (unsigned char)pktin.data[i])); + debug(("Got packet len=%d pad=%d\r\n", st->len, st->pad)); + for (st->i = 0; st->i < st->packetlen; st->i++) + debug((" %02x", (unsigned char)pktin.data[st->i])); debug(("\r\n")); #endif /* * Check the MAC. */ - if (scmac && !scmac->verify(pktin.data, len+4, incoming_sequence)) - fatalbox("Incorrect MAC received on packet"); - incoming_sequence++; /* whether or not we MACed */ + if (scmac && !scmac->verify(pktin.data, st->len+4, st->incoming_sequence)) { + bombout(("Incorrect MAC received on packet")); + crReturn(0); + } + st->incoming_sequence++; /* whether or not we MACed */ + + /* + * Decompress packet payload. + */ + { + unsigned char *newpayload; + int newlen; + if (sccomp && sccomp->decompress(pktin.data+5, pktin.length-5, + &newpayload, &newlen)) { + if (pktin.maxlen < newlen+5) { + pktin.maxlen = newlen+5; + pktin.data = (pktin.data == NULL ? smalloc(pktin.maxlen+APIEXTRA) : + srealloc(pktin.data, pktin.maxlen+APIEXTRA)); + if (!pktin.data) + fatalbox("Out of memory"); + } + pktin.length = 5 + newlen; + memcpy(pktin.data+5, newpayload, newlen); +#if 0 + debug(("Post-decompression payload:\r\n")); + for (st->i = 0; st->i < newlen; st->i++) + debug((" %02x", (unsigned char)pktin.data[5+st->i])); + debug(("\r\n")); +#endif + + sfree(newpayload); + } + } pktin.savedpos = 6; pktin.type = pktin.data[5]; @@ -459,20 +621,7 @@ next_packet: crFinish(0); } -static void ssh_gotdata(unsigned char *data, int datalen) -{ - while (datalen > 0) { - if ( s_rdpkt(&data, &datalen) == 0 ) { - ssh_protocol(NULL, 0, 1); - if (ssh_state == SSH_STATE_CLOSED) { - return; - } - } - } -} - - -static void s_wrpkt_start(int type, int len) { +static void ssh1_pktout_size(int len) { int pad, biglen; len += 5; /* type and CRC */ @@ -485,39 +634,71 @@ static void s_wrpkt_start(int type, int len) { #ifdef MSCRYPTOAPI /* Allocate enough buffer space for extra block * for MS CryptEncrypt() */ - pktout.data = (pktout.data == NULL ? malloc(biglen+12) : - realloc(pktout.data, biglen+12)); + pktout.data = (pktout.data == NULL ? smalloc(biglen+12) : + srealloc(pktout.data, biglen+12)); #else - pktout.data = (pktout.data == NULL ? malloc(biglen+4) : - realloc(pktout.data, biglen+4)); + pktout.data = (pktout.data == NULL ? smalloc(biglen+4) : + srealloc(pktout.data, biglen+4)); #endif if (!pktout.data) fatalbox("Out of memory"); } + pktout.body = pktout.data+4+pad+1; +} +static void s_wrpkt_start(int type, int len) { + ssh1_pktout_size(len); pktout.type = type; - pktout.body = pktout.data+4+pad+1; } static void s_wrpkt(void) { int pad, len, biglen, i; unsigned long crc; + pktout.body[-1] = pktout.type; + + if (ssh1_compressing) { + unsigned char *compblk; + int complen; +#if 0 + debug(("Packet payload pre-compression:\n")); + for (i = -1; i < pktout.length; i++) + debug((" %02x", (unsigned char)pktout.body[i])); + debug(("\r\n")); +#endif + zlib_compress_block(pktout.body-1, pktout.length+1, + &compblk, &complen); + ssh1_pktout_size(complen-1); + memcpy(pktout.body-1, compblk, complen); + sfree(compblk); +#if 0 + debug(("Packet payload post-compression:\n")); + for (i = -1; i < pktout.length; i++) + debug((" %02x", (unsigned char)pktout.body[i])); + debug(("\r\n")); +#endif + } + len = pktout.length + 5; /* type and CRC */ pad = 8 - (len%8); biglen = len + pad; - pktout.body[-1] = pktout.type; for (i=0; iencrypt(pktout.data+4, biglen); - s_write(pktout.data, biglen+4); + sk_write(s, pktout.data, biglen+4); } /* @@ -604,108 +785,6 @@ static void send_packet(int pkttype, ...) s_wrpkt(); } - -/* - * Connect to specified host and port. - * Returns an error message, or NULL on success. - * Also places the canonical host name into `realhost'. - */ -static char *connect_to_host(char *host, int port, char **realhost) -{ - SOCKADDR_IN addr; - struct hostent *h; - unsigned long a; -#ifdef FWHACK - char *FWhost; - int FWport; -#endif - - savedhost = malloc(1+strlen(host)); - if (!savedhost) - fatalbox("Out of memory"); - strcpy(savedhost, host); - - if (port < 0) - port = 22; /* default ssh port */ - -#ifdef FWHACK - FWhost = host; - FWport = port; - host = FWSTR; - port = 23; -#endif - - /* - * Try to find host. - */ - if ( (a = inet_addr(host)) == (unsigned long) INADDR_NONE) { - if ( (h = gethostbyname(host)) == NULL) - switch (WSAGetLastError()) { - case WSAENETDOWN: return "Network is down"; - case WSAHOST_NOT_FOUND: case WSANO_DATA: - return "Host does not exist"; - case WSATRY_AGAIN: return "Host not found"; - default: return "gethostbyname: unknown error"; - } - memcpy (&a, h->h_addr, sizeof(a)); - *realhost = h->h_name; - } else - *realhost = host; -#ifdef FWHACK - *realhost = FWhost; -#endif - a = ntohl(a); - - /* - * Open socket. - */ - s = socket(AF_INET, SOCK_STREAM, 0); - if (s == INVALID_SOCKET) - switch (WSAGetLastError()) { - case WSAENETDOWN: return "Network is down"; - case WSAEAFNOSUPPORT: return "TCP/IP support not present"; - default: return "socket(): unknown error"; - } - - /* - * Bind to local address. - */ - addr.sin_family = AF_INET; - addr.sin_addr.s_addr = htonl(INADDR_ANY); - addr.sin_port = htons(0); - if (bind (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR) - switch (WSAGetLastError()) { - case WSAENETDOWN: return "Network is down"; - default: return "bind(): unknown error"; - } - - /* - * Connect to remote address. - */ - addr.sin_addr.s_addr = htonl(a); - addr.sin_port = htons((short)port); - if (connect (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR) - switch (WSAGetLastError()) { - case WSAENETDOWN: return "Network is down"; - case WSAECONNREFUSED: return "Connection refused"; - case WSAENETUNREACH: return "Network is unreachable"; - case WSAEHOSTUNREACH: return "No route to host"; - default: return "connect(): unknown error"; - } - -#ifdef FWHACK - send(s, "connect ", 8, 0); - send(s, FWhost, strlen(FWhost), 0); - { - char buf[20]; - sprintf(buf, " %d\n", FWport); - send (s, buf, strlen(buf), 0); - } -#endif - - return NULL; -} - static int ssh_versioncmp(char *a, char *b) { char *ae, *be; unsigned long av, bv; @@ -727,7 +806,7 @@ static int ssh_versioncmp(char *a, char *b) { * state. */ #include -void sha_string(SHA_State *s, void *str, int len) { +static void sha_string(SHA_State *s, void *str, int len) { unsigned char lenblk[4]; PUT_32BIT(lenblk, len); SHA_Bytes(s, lenblk, 4); @@ -737,54 +816,57 @@ void sha_string(SHA_State *s, void *str, int len) { /* * SSH2 packet construction functions. */ -void ssh2_pkt_adddata(void *data, int len) { - pktout.length += len; - if (pktout.maxlen < pktout.length) { - pktout.maxlen = pktout.length + 256; - pktout.data = (pktout.data == NULL ? malloc(pktout.maxlen+APIEXTRA) : - realloc(pktout.data, pktout.maxlen+APIEXTRA)); +static void ssh2_pkt_ensure(int length) { + if (pktout.maxlen < length) { + pktout.maxlen = length + 256; + pktout.data = (pktout.data == NULL ? smalloc(pktout.maxlen+APIEXTRA) : + srealloc(pktout.data, pktout.maxlen+APIEXTRA)); if (!pktout.data) fatalbox("Out of memory"); } +} +static void ssh2_pkt_adddata(void *data, int len) { + pktout.length += len; + ssh2_pkt_ensure(pktout.length); memcpy(pktout.data+pktout.length-len, data, len); } -void ssh2_pkt_addbyte(unsigned char byte) { +static void ssh2_pkt_addbyte(unsigned char byte) { ssh2_pkt_adddata(&byte, 1); } -void ssh2_pkt_init(int pkt_type) { +static void ssh2_pkt_init(int pkt_type) { pktout.length = 5; ssh2_pkt_addbyte((unsigned char)pkt_type); } -void ssh2_pkt_addbool(unsigned char value) { +static void ssh2_pkt_addbool(unsigned char value) { ssh2_pkt_adddata(&value, 1); } -void ssh2_pkt_adduint32(unsigned long value) { +static void ssh2_pkt_adduint32(unsigned long value) { unsigned char x[4]; PUT_32BIT(x, value); ssh2_pkt_adddata(x, 4); } -void ssh2_pkt_addstring_start(void) { +static void ssh2_pkt_addstring_start(void) { ssh2_pkt_adduint32(0); pktout.savedpos = pktout.length; } -void ssh2_pkt_addstring_str(char *data) { +static void ssh2_pkt_addstring_str(char *data) { ssh2_pkt_adddata(data, strlen(data)); PUT_32BIT(pktout.data + pktout.savedpos - 4, pktout.length - pktout.savedpos); } -void ssh2_pkt_addstring_data(char *data, int len) { +static void ssh2_pkt_addstring_data(char *data, int len) { ssh2_pkt_adddata(data, len); PUT_32BIT(pktout.data + pktout.savedpos - 4, pktout.length - pktout.savedpos); } -void ssh2_pkt_addstring(char *data) { +static void ssh2_pkt_addstring(char *data) { ssh2_pkt_addstring_start(); ssh2_pkt_addstring_str(data); } -char *ssh2_mpint_fmt(Bignum b, int *len) { +static char *ssh2_mpint_fmt(Bignum b, int *len) { unsigned char *p; int i, n = b[0]; - p = malloc(n * 2 + 1); + p = smalloc(n * 2 + 1); if (!p) fatalbox("out of memory"); p[0] = 0; @@ -799,19 +881,39 @@ char *ssh2_mpint_fmt(Bignum b, int *len) { *len = n*2+1-i; return p; } -void ssh2_pkt_addmp(Bignum b) { +static void ssh2_pkt_addmp(Bignum b) { unsigned char *p; int len; p = ssh2_mpint_fmt(b, &len); ssh2_pkt_addstring_start(); ssh2_pkt_addstring_data(p, len); - free(p); + sfree(p); } -void ssh2_pkt_send(void) { +static void ssh2_pkt_send(void) { int cipherblk, maclen, padding, i; static unsigned long outgoing_sequence = 0; /* + * Compress packet payload. + */ +#if 0 + debug(("Pre-compression payload:\r\n")); + for (i = 5; i < pktout.length; i++) + debug((" %02x", (unsigned char)pktout.data[i])); + debug(("\r\n")); +#endif + { + unsigned char *newpayload; + int newlen; + if (cscomp && cscomp->compress(pktout.data+5, pktout.length-5, + &newpayload, &newlen)) { + pktout.length = 5; + ssh2_pkt_adddata(newpayload, newlen); + sfree(newpayload); + } + } + + /* * Add padding. At least four bytes, and must also bring total * length (minus MAC) up to a multiple of the block size. */ @@ -819,6 +921,8 @@ void ssh2_pkt_send(void) { cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */ padding = 4; padding += (cipherblk - (pktout.length + padding) % cipherblk) % cipherblk; + maclen = csmac ? csmac->len : 0; + ssh2_pkt_ensure(pktout.length + padding + maclen); pktout.data[4] = padding; for (i = 0; i < padding; i++) pktout.data[pktout.length + i] = random_byte(); @@ -837,9 +941,8 @@ void ssh2_pkt_send(void) { if (cscipher) cscipher->encrypt(pktout.data, pktout.length + padding); - maclen = csmac ? csmac->len : 0; - s_write(pktout.data, pktout.length + padding + maclen); + sk_write(s, pktout.data, pktout.length + padding + maclen); } #if 0 @@ -851,22 +954,22 @@ void bndebug(char *string, Bignum b) { for (i = 0; i < len; i++) debug((" %02x", p[i])); debug(("\r\n")); - free(p); + sfree(p); } #endif -void sha_mpint(SHA_State *s, Bignum b) { +static void sha_mpint(SHA_State *s, Bignum b) { unsigned char *p; int len; p = ssh2_mpint_fmt(b, &len); sha_string(s, p, len); - free(p); + sfree(p); } /* * SSH2 packet decode functions. */ -unsigned long ssh2_pkt_getuint32(void) { +static unsigned long ssh2_pkt_getuint32(void) { unsigned long value; if (pktin.length - pktin.savedpos < 4) return 0; /* arrgh, no way to decline (FIXME?) */ @@ -874,7 +977,7 @@ unsigned long ssh2_pkt_getuint32(void) { pktin.savedpos += 4; return value; } -void ssh2_pkt_getstring(char **p, int *length) { +static void ssh2_pkt_getstring(char **p, int *length) { *p = NULL; if (pktin.length - pktin.savedpos < 4) return; @@ -885,7 +988,7 @@ void ssh2_pkt_getstring(char **p, int *length) { *p = pktin.data+pktin.savedpos; pktin.savedpos += *length; } -Bignum ssh2_pkt_getmp(void) { +static Bignum ssh2_pkt_getmp(void) { char *p; int i, j, length; Bignum b; @@ -893,8 +996,10 @@ Bignum ssh2_pkt_getmp(void) { ssh2_pkt_getstring(&p, &length); if (!p) return NULL; - if (p[0] & 0x80) - fatalbox("internal error: Can't handle negative mpints"); + if (p[0] & 0x80) { + bombout(("internal error: Can't handle negative mpints")); + return NULL; + } b = newbn((length+1)/2); for (i = 0; i < length; i++) { j = length - 1 - i; @@ -903,36 +1008,39 @@ Bignum ssh2_pkt_getmp(void) { else b[j/2+1] |= ((unsigned char)p[i]); } + while (b[0] > 1 && b[b[0]] == 0) b[0]--; return b; } -static int do_ssh_init(void) { - char c, *vsp; - char version[10]; - char vstring[80]; - char vlog[sizeof(vstring)+20]; - int i; +static int do_ssh_init(unsigned char c) { + static char *vsp; + static char version[10]; + static char vstring[80]; + static char vlog[sizeof(vstring)+20]; + static int i; -#ifdef FWHACK + crBegin; + + /* Search for the string "SSH-" in the input. */ i = 0; - while (s_read(&c, 1) == 1) { - if (c == 'S' && i < 2) i++; - else if (c == 'S' && i == 2) i = 2; - else if (c == 'H' && i == 2) break; + while (1) { + static const int transS[] = { 1, 2, 2, 1 }; + static const int transH[] = { 0, 0, 3, 0 }; + static const int transminus[] = { 0, 0, 0, -1 }; + if (c == 'S') i = transS[i]; + else if (c == 'H') i = transH[i]; + else if (c == '-') i = transminus[i]; else i = 0; + if (i < 0) + break; + crReturn(1); /* get another character */ } -#else - if (s_read(&c,1) != 1 || c != 'S') return 0; - if (s_read(&c,1) != 1 || c != 'S') return 0; - if (s_read(&c,1) != 1 || c != 'H') return 0; -#endif + strcpy(vstring, "SSH-"); vsp = vstring+4; - if (s_read(&c,1) != 1 || c != '-') return 0; i = 0; while (1) { - if (s_read(&c,1) != 1) - return 0; + crReturn(1); /* get another char */ if (vsp < vstring+sizeof(vstring)-1) *vsp++ = c; if (i >= 0) { @@ -946,6 +1054,9 @@ static int do_ssh_init(void) { break; } + ssh_agentfwd_enabled = FALSE; + rdpkt2_state.incoming_sequence = 0; + *vsp = 0; sprintf(vlog, "Server version: %s", vstring); vlog[strcspn(vlog, "\r\n")] = '\0'; @@ -960,17 +1071,17 @@ static int do_ssh_init(void) { * This is a v2 server. Begin v2 protocol. */ char *verstring = "SSH-2.0-PuTTY"; - SHA_Init(&exhash); + SHA_Init(&exhashbase); /* * Hash our version string and their version string. */ - sha_string(&exhash, verstring, strlen(verstring)); - sha_string(&exhash, vstring, strcspn(vstring, "\r\n")); + sha_string(&exhashbase, verstring, strlen(verstring)); + sha_string(&exhashbase, vstring, strcspn(vstring, "\r\n")); sprintf(vstring, "%s\n", verstring); sprintf(vlog, "We claim version: %s", verstring); logevent(vlog); logevent("Using SSH protocol version 2"); - s_write(vstring, strlen(vstring)); + sk_write(s, vstring, strlen(vstring)); ssh_protocol = ssh2_protocol; ssh_version = 2; s_rdpkt = ssh2_rdpkt; @@ -984,16 +1095,144 @@ static int do_ssh_init(void) { vlog[strcspn(vlog, "\r\n")] = '\0'; logevent(vlog); logevent("Using SSH protocol version 1"); - s_write(vstring, strlen(vstring)); + sk_write(s, vstring, strlen(vstring)); ssh_protocol = ssh1_protocol; ssh_version = 1; s_rdpkt = ssh1_rdpkt; } - ssh_send_ok = 0; + ssh_state = SSH_STATE_BEFORE_SIZE; + + crFinish(0); +} + +static void ssh_gotdata(unsigned char *data, int datalen) +{ + crBegin; + + /* + * To begin with, feed the characters one by one to the + * protocol initialisation / selection function do_ssh_init(). + * When that returns 0, we're done with the initial greeting + * exchange and can move on to packet discipline. + */ + while (1) { + int ret; + if (datalen == 0) + crReturnV; /* more data please */ + ret = do_ssh_init(*data); + data++; datalen--; + if (ret == 0) + break; + } + + /* + * We emerge from that loop when the initial negotiation is + * over and we have selected an s_rdpkt function. Now pass + * everything to s_rdpkt, and then pass the resulting packets + * to the proper protocol handler. + */ + if (datalen == 0) + crReturnV; + while (1) { + while (datalen > 0) { + if ( s_rdpkt(&data, &datalen) == 0 ) { + ssh_protocol(NULL, 0, 1); + if (ssh_state == SSH_STATE_CLOSED) { + return; + } + } + } + crReturnV; + } + crFinishV; +} + +static int ssh_receive(Socket skt, int urgent, char *data, int len) { + if (urgent==3) { + /* A socket error has occurred. */ + connection_fatal(data); + len = 0; + } + if (!len) { + /* Connection has closed. */ + ssh_state = SSH_STATE_CLOSED; + sk_close(s); + s = NULL; + return 0; + } + ssh_gotdata (data, len); + if (ssh_state == SSH_STATE_CLOSED) { + if (s) { + sk_close(s); + s = NULL; + } + return 0; + } return 1; } /* + * Connect to specified host and port. + * Returns an error message, or NULL on success. + * Also places the canonical host name into `realhost'. + */ +static char *connect_to_host(char *host, int port, char **realhost) +{ + SockAddr addr; + char *err; +#ifdef FWHACK + char *FWhost; + int FWport; +#endif + + savedhost = smalloc(1+strlen(host)); + if (!savedhost) + fatalbox("Out of memory"); + strcpy(savedhost, host); + + if (port < 0) + port = 22; /* default ssh port */ + savedport = port; + +#ifdef FWHACK + FWhost = host; + FWport = port; + host = FWSTR; + port = 23; +#endif + + /* + * Try to find host. + */ + addr = sk_namelookup(host, realhost); + if ( (err = sk_addr_error(addr)) ) + return err; + +#ifdef FWHACK + *realhost = FWhost; +#endif + + /* + * Open socket. + */ + s = sk_new(addr, port, 0, ssh_receive); + if ( (err = sk_socket_error(s)) ) + return err; + +#ifdef FWHACK + sk_write(s, "connect ", 8); + sk_write(s, FWhost, strlen(FWhost)); + { + char buf[20]; + sprintf(buf, " %d\n", FWport); + sk_write(s, buf, strlen(buf)); + } +#endif + + return NULL; +} + +/* * Handle the key exchange and user authentication phases. */ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) @@ -1007,13 +1246,16 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) static int tried_publickey; static unsigned char session_id[16]; int cipher_type; + static char username[100]; crBegin; if (!ispkt) crWaitUntil(ispkt); - if (pktin.type != SSH1_SMSG_PUBLIC_KEY) - fatalbox("Public key packet not received"); + if (pktin.type != SSH1_SMSG_PUBLIC_KEY) { + bombout(("Public key packet not received")); + crReturn(0); + } logevent("Received public keys"); @@ -1023,21 +1265,15 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) j = makekey(pktin.body+8+i, &hostkey, &keystr2, 0); /* - * Hash the host key and print the hash in the log box. Just as - * a last resort in case the registry's host key checking is - * compromised, we'll allow the user some ability to verify - * host keys by eye. + * Log the host key fingerprint. */ - MD5Init(&md5c); - MD5Update(&md5c, keystr2, hostkey.bytes); - MD5Final(session_id, &md5c); { char logmsg[80]; - int i; - logevent("Host key MD5 is:"); + logevent("Host key fingerprint is:"); strcpy(logmsg, " "); - for (i = 0; i < 16; i++) - sprintf(logmsg+strlen(logmsg), "%02x", session_id[i]); + hostkey.comment = NULL; + rsa_fingerprint(logmsg+strlen(logmsg), sizeof(logmsg)-strlen(logmsg), + &hostkey); logevent(logmsg); } @@ -1055,7 +1291,7 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes); - rsabuf = malloc(len); + rsabuf = smalloc(len); if (!rsabuf) fatalbox("Out of memory"); @@ -1067,12 +1303,14 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) * First format the key into a string. */ int len = rsastr_len(&hostkey); - char *keystr = malloc(len); + char fingerprint[100]; + char *keystr = smalloc(len); if (!keystr) fatalbox("Out of memory"); rsastr_fmt(keystr, &hostkey); - verify_ssh_host_key(savedhost, keystr); - free(keystr); + rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey); + verify_ssh_host_key(savedhost, savedport, "rsa", keystr, fingerprint); + sfree(keystr); } for (i=0; i<32; i++) { @@ -1114,27 +1352,29 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) logevent("Trying to enable encryption..."); - free(rsabuf); + sfree(rsabuf); - cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish : + cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 : cipher_type == SSH_CIPHER_DES ? &ssh_des : &ssh_3des; cipher->sesskey(session_key); crWaitUntil(ispkt); - if (pktin.type != SSH1_SMSG_SUCCESS) - fatalbox("Encryption not successfully enabled"); + if (pktin.type != SSH1_SMSG_SUCCESS) { + bombout(("Encryption not successfully enabled")); + crReturn(0); + } logevent("Successfully started encryption"); fflush(stdout); { - static char username[100]; static int pos = 0; static char c; - if ((flags & FLAG_CONNECTION) && !*cfg.username) { + if ((flags & FLAG_INTERACTIVE) && !*cfg.username) { c_write("login as: ", 10); + ssh_send_ok = 1; while (pos >= 0) { crWaitUntil(!ispkt); while (inlen--) switch (c = *in++) { @@ -1170,20 +1410,20 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) c_write("\r\n", 2); username[strcspn(username, "\n\r")] = '\0'; } else { - char stuff[200]; strncpy(username, cfg.username, 99); username[99] = '\0'; - if (flags & FLAG_VERBOSE) { - sprintf(stuff, "Sent username \"%s\".\r\n", username); - c_write(stuff, strlen(stuff)); - } } send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END); { - char userlog[20+sizeof(username)]; + char userlog[22+sizeof(username)]; sprintf(userlog, "Sent username \"%s\"", username); logevent(userlog); + if (flags & FLAG_INTERACTIVE && + (!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) { + strcat(userlog, "\r\n"); + c_write(userlog, strlen(userlog)); + } } } @@ -1193,6 +1433,7 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) while (pktin.type == SSH1_SMSG_FAILURE) { static char password[100]; + static char prompt[200]; static int pos; static char c; static int pwpkt_type; @@ -1227,12 +1468,16 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) for (i = 0; i < nkeys; i++) { static struct RSAKey key; static Bignum challenge; + static char *commentp; + static int commentlen; { char buf[64]; sprintf(buf, "Trying Pageant key #%d", i); logevent(buf); } p += 4; p += ssh1_read_bignum(p, &key.exponent); p += ssh1_read_bignum(p, &key.modulus); + commentlen = GET_32BIT(p); p += 4; + commentp = p; p += commentlen; send_packet(SSH1_CMSG_AUTH_RSA, PKT_BIGNUM, key.modulus, PKT_END); crWaitUntil(ispkt); @@ -1251,7 +1496,7 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) len += ssh1_bignum_length(challenge); len += 16; /* session id */ len += 4; /* response format */ - agentreq = malloc(4 + len); + agentreq = smalloc(4 + len); PUT_32BIT(agentreq, len); q = agentreq + 4; *q++ = SSH_AGENTC_RSA_CHALLENGE; @@ -1263,22 +1508,28 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) memcpy(q, session_id, 16); q += 16; PUT_32BIT(q, 1); /* response format */ agent_query(agentreq, len+4, &ret, &retlen); - free(agentreq); + sfree(agentreq); if (ret) { if (ret[4] == SSH_AGENT_RSA_RESPONSE) { logevent("Sending Pageant's response"); send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE, PKT_DATA, ret+5, 16, PKT_END); - free(ret); + sfree(ret); crWaitUntil(ispkt); if (pktin.type == SSH1_SMSG_SUCCESS) { logevent("Pageant's response accepted"); + if (flags & FLAG_VERBOSE) { + c_write("Authenticated using RSA key \"", + 29); + c_write(commentp, commentlen); + c_write("\" from agent\r\n", 14); + } authed = TRUE; } else logevent("Pageant's response not accepted"); } else { logevent("Pageant failed to answer challenge"); - free(ret); + sfree(ret); } } else { logevent("No reply received from Pageant"); @@ -1294,12 +1545,74 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) if (authed) break; } - if (*cfg.keyfile && !tried_publickey) - pwpkt_type = SSH1_CMSG_AUTH_RSA; + if (*cfg.keyfile && !tried_publickey) + pwpkt_type = SSH1_CMSG_AUTH_RSA; + + if (pktin.type == SSH1_SMSG_FAILURE && + cfg.try_tis_auth && + (supported_auths_mask & (1< sizeof(prompt)-1) + challengelen = sizeof(prompt)-1; /* prevent overrun */ + memcpy(prompt, pktin.body+4, challengelen); + prompt[challengelen] = '\0'; + } + } + if (pktin.type == SSH1_SMSG_FAILURE && + cfg.try_tis_auth && + (supported_auths_mask & (1< sizeof(prompt)-1) + challengelen = sizeof(prompt)-1; /* prevent overrun */ + memcpy(prompt, pktin.body+4, challengelen); + strncpy(prompt + challengelen, "\r\nResponse : ", + sizeof(prompt)-challengelen); + prompt[sizeof(prompt)-1] = '\0'; + } + } + if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) { + sprintf(prompt, "%.90s@%.90s's password: ", + username, savedhost); + } + if (pwpkt_type == SSH1_CMSG_AUTH_RSA) { + char *comment = NULL; + if (flags & FLAG_VERBOSE) + c_write("Trying public key authentication.\r\n", 35); + if (!rsakey_encrypted(cfg.keyfile, &comment)) { + if (flags & FLAG_VERBOSE) + c_write("No passphrase required.\r\n", 25); + goto tryauth; + } + sprintf(prompt, "Passphrase for key \"%.100s\": ", comment); + sfree(comment); + } - if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD && !FLAG_WINDOWED) { - char prompt[200]; - sprintf(prompt, "%s@%s's password: ", cfg.username, savedhost); + if (ssh_get_password) { if (!ssh_get_password(prompt, password, sizeof(password))) { /* * get_password failed to get a password (for @@ -1312,60 +1625,9 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) crReturn(1); } } else { - - if (pktin.type == SSH1_SMSG_FAILURE && - cfg.try_tis_auth && - (supported_auths_mask & (1<= 0) { crWaitUntil(!ispkt); while (inlen--) switch (c = *in++) { @@ -1392,8 +1654,7 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) } } c_write("\r\n", 2); - - } + } tryauth: if (pwpkt_type == SSH1_CMSG_AUTH_RSA) { @@ -1407,7 +1668,7 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) static unsigned char buffer[32]; tried_publickey = 1; - i = loadrsakey(cfg.keyfile, &pubkey, password); + i = loadrsakey(cfg.keyfile, &pubkey, NULL, password); if (i == 0) { c_write("Couldn't load public key from ", 30); c_write(cfg.keyfile, strlen(cfg.keyfile)); @@ -1428,12 +1689,13 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) crWaitUntil(ispkt); if (pktin.type == SSH1_SMSG_FAILURE) { - if (flags & FLAG_VERBOSE) - c_write("Server refused our public key.\r\n", 32); + c_write("Server refused our public key.\r\n", 32); continue; /* go and try password */ } - if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) - fatalbox("Bizarre response to offer of public key"); + if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) { + bombout(("Bizarre response to offer of public key")); + crReturn(0); + } ssh1_read_bignum(pktin.body, &challenge); response = rsadecrypt(challenge, &pubkey); freebn(pubkey.private_exponent); /* burn the evidence */ @@ -1458,7 +1720,8 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) 45); continue; /* go and try password */ } else if (pktin.type != SSH1_SMSG_SUCCESS) { - fatalbox("Bizarre response to RSA authentication response"); + bombout(("Bizarre response to RSA authentication response")); + crReturn(0); } break; /* we're through! */ @@ -1477,7 +1740,8 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) ssh_state = SSH_STATE_CLOSED; crReturn(1); } else if (pktin.type != SSH1_SMSG_SUCCESS) { - fatalbox("Strange packet received, type %d", pktin.type); + bombout(("Strange packet received, type %d", pktin.type)); + crReturn(0); } } @@ -1486,6 +1750,36 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) crFinish(1); } +void sshfwd_close(struct ssh_channel *c) { + if (c) { + if (ssh_version == 1) { + send_packet(SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid, PKT_END); + } else { + ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE); + ssh2_pkt_adduint32(c->remoteid); + ssh2_pkt_send(); + } + c->closes = 1; + if (c->type == CHAN_X11) { + c->u.x11.s = NULL; + logevent("X11 connection terminated"); + } + } +} + +void sshfwd_write(struct ssh_channel *c, char *buf, int len) { + if (ssh_version == 1) { + send_packet(SSH1_MSG_CHANNEL_DATA, + PKT_INT, c->remoteid, + PKT_INT, len, + PKT_DATA, buf, len, + PKT_END); + } else { + ssh2_add_channel_data(c, buf, len); + ssh2_try_send(c); + } +} + static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) { crBegin; @@ -1497,6 +1791,41 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) { if (ssh_state == SSH_STATE_CLOSED) crReturnV; + if (cfg.agentfwd && agent_exists()) { + logevent("Requesting agent forwarding"); + send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END); + do { crReturnV; } while (!ispkt); + if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) { + bombout(("Protocol confusion")); + crReturnV; + } else if (pktin.type == SSH1_SMSG_FAILURE) { + logevent("Agent forwarding refused"); + } else { + logevent("Agent forwarding enabled"); + ssh_agentfwd_enabled = TRUE; + } + } + + if (cfg.x11_forward) { + char proto[20], data[64]; + logevent("Requesting X11 forwarding"); + x11_invent_auth(proto, sizeof(proto), data, sizeof(data)); + send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING, + PKT_STR, proto, PKT_STR, data, + PKT_INT, 0, + PKT_END); + do { crReturnV; } while (!ispkt); + if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) { + bombout(("Protocol confusion")); + crReturnV; + } else if (pktin.type == SSH1_SMSG_FAILURE) { + logevent("X11 forwarding refused"); + } else { + logevent("X11 forwarding enabled"); + ssh_X11_fwd_enabled = TRUE; + } + } + if (!cfg.nopty) { send_packet(SSH1_CMSG_REQUEST_PTY, PKT_STR, cfg.termtype, @@ -1507,13 +1836,29 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) { ssh_state = SSH_STATE_INTERMED; do { crReturnV; } while (!ispkt); if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) { - fatalbox("Protocol confusion"); + bombout(("Protocol confusion")); + crReturnV; } else if (pktin.type == SSH1_SMSG_FAILURE) { c_write("Server refused to allocate pty\r\n", 32); } logevent("Allocated pty"); } + if (cfg.compression) { + send_packet(SSH1_CMSG_REQUEST_COMPRESSION, PKT_INT, 6, PKT_END); + do { crReturnV; } while (!ispkt); + if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) { + bombout(("Protocol confusion")); + crReturnV; + } else if (pktin.type == SSH1_SMSG_FAILURE) { + c_write("Server refused to compress\r\n", 32); + } + logevent("Started compression"); + ssh1_compressing = TRUE; + zlib_compress_init(); + zlib_decompress_init(); + } + if (*cfg.remote_cmd) send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cfg.remote_cmd, PKT_END); else @@ -1523,18 +1868,173 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) { ssh_state = SSH_STATE_SESSION; if (size_needed) ssh_size(); + if (eof_needed) + ssh_special(TS_EOF); ssh_send_ok = 1; + ssh_channels = newtree234(ssh_channelcmp); + begin_session(); while (1) { crReturnV; if (ispkt) { if (pktin.type == SSH1_SMSG_STDOUT_DATA || pktin.type == SSH1_SMSG_STDERR_DATA) { long len = GET_32BIT(pktin.body); - c_write(pktin.body+4, len); + from_backend(pktin.type == SSH1_SMSG_STDERR_DATA, + pktin.body+4, len); } else if (pktin.type == SSH1_MSG_DISCONNECT) { ssh_state = SSH_STATE_CLOSED; logevent("Received disconnect request"); + crReturnV; + } else if (pktin.type == SSH1_SMSG_X11_OPEN) { + /* Remote side is trying to open a channel to talk to our + * X-Server. Give them back a local channel number. */ + unsigned i; + struct ssh_channel *c, *d; + enum234 e; + + logevent("Received X11 connect request"); + /* Refuse if X11 forwarding is disabled. */ + if (!ssh_X11_fwd_enabled) { + send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE, + PKT_INT, GET_32BIT(pktin.body), + PKT_END); + logevent("Rejected X11 connect request"); + } else { + c = smalloc(sizeof(struct ssh_channel)); + + if ( x11_init(&c->u.x11.s, cfg.x11_display, c) != NULL ) { + logevent("opening X11 forward connection failed"); + sfree(c); + send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE, + PKT_INT, GET_32BIT(pktin.body), + PKT_END); + } else { + logevent("opening X11 forward connection succeeded"); + for (i=1, d = first234(ssh_channels, &e); d; d = next234(&e)) { + if (d->localid > i) + break; /* found a free number */ + i = d->localid + 1; + } + c->remoteid = GET_32BIT(pktin.body); + c->localid = i; + c->closes = 0; + c->type = CHAN_X11; /* identify channel type */ + add234(ssh_channels, c); + send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION, + PKT_INT, c->remoteid, PKT_INT, c->localid, + PKT_END); + logevent("Opened X11 forward channel"); + } + } + } else if (pktin.type == SSH1_SMSG_AGENT_OPEN) { + /* Remote side is trying to open a channel to talk to our + * agent. Give them back a local channel number. */ + unsigned i; + struct ssh_channel *c; + enum234 e; + + /* Refuse if agent forwarding is disabled. */ + if (!ssh_agentfwd_enabled) { + send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE, + PKT_INT, GET_32BIT(pktin.body), + PKT_END); + } else { + i = 1; + for (c = first234(ssh_channels, &e); c; c = next234(&e)) { + if (c->localid > i) + break; /* found a free number */ + i = c->localid + 1; + } + c = smalloc(sizeof(struct ssh_channel)); + c->remoteid = GET_32BIT(pktin.body); + c->localid = i; + c->closes = 0; + c->type = CHAN_AGENT; /* identify channel type */ + c->u.a.lensofar = 0; + add234(ssh_channels, c); + send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION, + PKT_INT, c->remoteid, PKT_INT, c->localid, + PKT_END); + } + } else if (pktin.type == SSH1_MSG_CHANNEL_CLOSE || + pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) { + /* Remote side closes a channel. */ + unsigned i = GET_32BIT(pktin.body); + struct ssh_channel *c; + c = find234(ssh_channels, &i, ssh_channelfind); + if (c) { + int closetype; + closetype = (pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2); + send_packet(pktin.type, PKT_INT, c->remoteid, PKT_END); + if ((c->closes == 0) && (c->type == CHAN_X11)) { + logevent("X11 connection closed"); + assert(c->u.x11.s != NULL); + x11_close(c->u.x11.s); + c->u.x11.s = NULL; + } + c->closes |= closetype; + if (c->closes == 3) { + del234(ssh_channels, c); + sfree(c); + } + } + } else if (pktin.type == SSH1_MSG_CHANNEL_DATA) { + /* Data sent down one of our channels. */ + int i = GET_32BIT(pktin.body); + int len = GET_32BIT(pktin.body+4); + unsigned char *p = pktin.body+8; + struct ssh_channel *c; + c = find234(ssh_channels, &i, ssh_channelfind); + if (c) { + switch(c->type) { + case CHAN_X11: + x11_send(c->u.x11.s, p, len); + break; + case CHAN_AGENT: + /* Data for an agent message. Buffer it. */ + while (len > 0) { + if (c->u.a.lensofar < 4) { + int l = min(4 - c->u.a.lensofar, len); + memcpy(c->u.a.msglen + c->u.a.lensofar, p, l); + p += l; len -= l; c->u.a.lensofar += l; + } + if (c->u.a.lensofar == 4) { + c->u.a.totallen = 4 + GET_32BIT(c->u.a.msglen); + c->u.a.message = smalloc(c->u.a.totallen); + memcpy(c->u.a.message, c->u.a.msglen, 4); + } + if (c->u.a.lensofar >= 4 && len > 0) { + int l = min(c->u.a.totallen - c->u.a.lensofar, len); + memcpy(c->u.a.message + c->u.a.lensofar, p, l); + p += l; len -= l; c->u.a.lensofar += l; + } + if (c->u.a.lensofar == c->u.a.totallen) { + void *reply, *sentreply; + int replylen; + agent_query(c->u.a.message, c->u.a.totallen, + &reply, &replylen); + if (reply) + sentreply = reply; + else { + /* Fake SSH_AGENT_FAILURE. */ + sentreply = "\0\0\0\1\5"; + replylen = 5; + } + send_packet(SSH1_MSG_CHANNEL_DATA, + PKT_INT, c->remoteid, + PKT_INT, replylen, + PKT_DATA, sentreply, replylen, + PKT_END); + if (reply) + sfree(reply); + sfree(c->u.a.message); + c->u.a.lensofar = 0; + } + } + break; + } + } } else if (pktin.type == SSH1_SMSG_SUCCESS) { /* may be from EXEC_SHELL on some servers */ } else if (pktin.type == SSH1_SMSG_FAILURE) { @@ -1543,11 +2043,17 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) { } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) { send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END); } else { - fatalbox("Strange packet received: type %d", pktin.type); + bombout(("Strange packet received: type %d", pktin.type)); + crReturnV; } } else { - send_packet(SSH1_CMSG_STDIN_DATA, - PKT_INT, inlen, PKT_DATA, in, inlen, PKT_END); + while (inlen > 0) { + int len = min(inlen, 512); + send_packet(SSH1_CMSG_STDIN_DATA, + PKT_INT, len, PKT_DATA, in, len, PKT_END); + in += len; + inlen -= len; + } } } @@ -1557,7 +2063,7 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) { /* * Utility routine for decoding comma-separated strings in KEXINIT. */ -int in_commasep_string(char *needle, char *haystack, int haylen) { +static int in_commasep_string(char *needle, char *haystack, int haylen) { int needlen = strlen(needle); while (1) { /* @@ -1584,7 +2090,7 @@ int in_commasep_string(char *needle, char *haystack, int haylen) { /* * SSH2 key creation method. */ -void ssh2_mkkey(Bignum K, char *H, char chr, char *keyspace) { +static void ssh2_mkkey(Bignum K, char *H, char chr, char *keyspace) { SHA_State s; /* First 20 bytes. */ SHA_Init(&s); @@ -1609,19 +2115,53 @@ static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt) static int i, len; static char *str; static Bignum e, f, K; - static struct ssh_cipher *cscipher_tobe = NULL; - static struct ssh_cipher *sccipher_tobe = NULL; - static struct ssh_mac *csmac_tobe = NULL; - static struct ssh_mac *scmac_tobe = NULL; - static struct ssh_compress *cscomp_tobe = NULL; - static struct ssh_compress *sccomp_tobe = NULL; - static char *hostkeydata, *sigdata, *keystr; + static const struct ssh_mac **maclist; + static int nmacs; + static const struct ssh_cipher *cscipher_tobe = NULL; + static const struct ssh_cipher *sccipher_tobe = NULL; + static const struct ssh_mac *csmac_tobe = NULL; + static const struct ssh_mac *scmac_tobe = NULL; + static const struct ssh_compress *cscomp_tobe = NULL; + static const struct ssh_compress *sccomp_tobe = NULL; + static char *hostkeydata, *sigdata, *keystr, *fingerprint; static int hostkeylen, siglen; + static void *hkey; /* actual host key */ static unsigned char exchange_hash[20]; static unsigned char keyspace[40]; + static const struct ssh_cipher *preferred_cipher; + static const struct ssh_compress *preferred_comp; + static int first_kex; crBegin; random_init(); + first_kex = 1; + + /* + * Set up the preferred cipher and compression. + */ + if (cfg.cipher == CIPHER_BLOWFISH) { + preferred_cipher = &ssh_blowfish_ssh2; + } else if (cfg.cipher == CIPHER_DES) { + logevent("Single DES not supported in SSH2; using 3DES"); + preferred_cipher = &ssh_3des_ssh2; + } else if (cfg.cipher == CIPHER_3DES) { + preferred_cipher = &ssh_3des_ssh2; + } else { + /* Shouldn't happen, but we do want to initialise to _something_. */ + preferred_cipher = &ssh_3des_ssh2; + } + if (cfg.compression) + preferred_comp = &ssh_zlib; + else + preferred_comp = &ssh_comp_none; + + /* + * Be prepared to work around the buggy MAC problem. + */ + if (cfg.buggymac) + maclist = buggymacs, nmacs = lenof(buggymacs); + else + maclist = macs, nmacs = lenof(macs); begin_key_exchange: /* @@ -1646,44 +2186,48 @@ static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt) } /* List client->server encryption algorithms. */ ssh2_pkt_addstring_start(); - for (i = 0; i < lenof(ciphers); i++) { - ssh2_pkt_addstring_str(ciphers[i]->name); - if (i < lenof(ciphers)-1) + for (i = 0; i < lenof(ciphers)+1; i++) { + const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1]; + ssh2_pkt_addstring_str(c->name); + if (i < lenof(ciphers)) ssh2_pkt_addstring_str(","); } /* List server->client encryption algorithms. */ ssh2_pkt_addstring_start(); - for (i = 0; i < lenof(ciphers); i++) { - ssh2_pkt_addstring_str(ciphers[i]->name); - if (i < lenof(ciphers)-1) + for (i = 0; i < lenof(ciphers)+1; i++) { + const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1]; + ssh2_pkt_addstring_str(c->name); + if (i < lenof(ciphers)) ssh2_pkt_addstring_str(","); } /* List client->server MAC algorithms. */ ssh2_pkt_addstring_start(); - for (i = 0; i < lenof(macs); i++) { - ssh2_pkt_addstring_str(macs[i]->name); - if (i < lenof(macs)-1) + for (i = 0; i < nmacs; i++) { + ssh2_pkt_addstring_str(maclist[i]->name); + if (i < nmacs-1) ssh2_pkt_addstring_str(","); } /* List server->client MAC algorithms. */ ssh2_pkt_addstring_start(); - for (i = 0; i < lenof(macs); i++) { - ssh2_pkt_addstring_str(macs[i]->name); - if (i < lenof(macs)-1) + for (i = 0; i < nmacs; i++) { + ssh2_pkt_addstring_str(maclist[i]->name); + if (i < nmacs-1) ssh2_pkt_addstring_str(","); } /* List client->server compression algorithms. */ ssh2_pkt_addstring_start(); - for (i = 0; i < lenof(compressions); i++) { - ssh2_pkt_addstring_str(compressions[i]->name); - if (i < lenof(compressions)-1) + for (i = 0; i < lenof(compressions)+1; i++) { + const struct ssh_compress *c = i==0 ? preferred_comp : compressions[i-1]; + ssh2_pkt_addstring_str(c->name); + if (i < lenof(compressions)) ssh2_pkt_addstring_str(","); } /* List server->client compression algorithms. */ ssh2_pkt_addstring_start(); - for (i = 0; i < lenof(compressions); i++) { - ssh2_pkt_addstring_str(compressions[i]->name); - if (i < lenof(compressions)-1) + for (i = 0; i < lenof(compressions)+1; i++) { + const struct ssh_compress *c = i==0 ? preferred_comp : compressions[i-1]; + ssh2_pkt_addstring_str(c->name); + if (i < lenof(compressions)) ssh2_pkt_addstring_str(","); } /* List client->server languages. Empty list. */ @@ -1694,7 +2238,10 @@ static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt) ssh2_pkt_addbool(FALSE); /* Reserved. */ ssh2_pkt_adduint32(0); + + exhash = exhashbase; sha_string(&exhash, pktout.data+5, pktout.length-5); + ssh2_pkt_send(); if (!ispkt) crWaitUntil(ispkt); @@ -1705,7 +2252,8 @@ static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt) * to. */ if (pktin.type != SSH2_MSG_KEXINIT) { - fatalbox("expected key exchange packet from server"); + bombout(("expected key exchange packet from server")); + crReturn(0); } kex = NULL; hostkey = NULL; cscipher_tobe = NULL; sccipher_tobe = NULL; csmac_tobe = NULL; scmac_tobe = NULL; cscomp_tobe = NULL; sccomp_tobe = NULL; @@ -1725,44 +2273,48 @@ static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt) } } ssh2_pkt_getstring(&str, &len); /* client->server cipher */ - for (i = 0; i < lenof(ciphers); i++) { - if (in_commasep_string(ciphers[i]->name, str, len)) { - cscipher_tobe = ciphers[i]; + for (i = 0; i < lenof(ciphers)+1; i++) { + const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1]; + if (in_commasep_string(c->name, str, len)) { + cscipher_tobe = c; break; } } ssh2_pkt_getstring(&str, &len); /* server->client cipher */ - for (i = 0; i < lenof(ciphers); i++) { - if (in_commasep_string(ciphers[i]->name, str, len)) { - sccipher_tobe = ciphers[i]; + for (i = 0; i < lenof(ciphers)+1; i++) { + const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1]; + if (in_commasep_string(c->name, str, len)) { + sccipher_tobe = c; break; } } ssh2_pkt_getstring(&str, &len); /* client->server mac */ - for (i = 0; i < lenof(macs); i++) { - if (in_commasep_string(macs[i]->name, str, len)) { - csmac_tobe = macs[i]; + for (i = 0; i < nmacs; i++) { + if (in_commasep_string(maclist[i]->name, str, len)) { + csmac_tobe = maclist[i]; break; } } ssh2_pkt_getstring(&str, &len); /* server->client mac */ - for (i = 0; i < lenof(macs); i++) { - if (in_commasep_string(macs[i]->name, str, len)) { - scmac_tobe = macs[i]; + for (i = 0; i < nmacs; i++) { + if (in_commasep_string(maclist[i]->name, str, len)) { + scmac_tobe = maclist[i]; break; } } ssh2_pkt_getstring(&str, &len); /* client->server compression */ - for (i = 0; i < lenof(compressions); i++) { - if (in_commasep_string(compressions[i]->name, str, len)) { - cscomp_tobe = compressions[i]; + for (i = 0; i < lenof(compressions)+1; i++) { + const struct ssh_compress *c = i==0 ? preferred_comp : compressions[i-1]; + if (in_commasep_string(c->name, str, len)) { + cscomp_tobe = c; break; } } ssh2_pkt_getstring(&str, &len); /* server->client compression */ - for (i = 0; i < lenof(compressions); i++) { - if (in_commasep_string(compressions[i]->name, str, len)) { - sccomp_tobe = compressions[i]; + for (i = 0; i < lenof(compressions)+1; i++) { + const struct ssh_compress *c = i==0 ? preferred_comp : compressions[i-1]; + if (in_commasep_string(c->name, str, len)) { + sccomp_tobe = c; break; } } @@ -1771,8 +2323,10 @@ static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt) * Currently we only support Diffie-Hellman and DSS, so let's * bomb out if those aren't selected. */ - if (kex != &ssh_diffiehellman || hostkey != &ssh_dss) - fatalbox("internal fault: chaos in SSH 2 transport layer"); + if (kex != &ssh_diffiehellman || hostkey != &ssh_dss) { + bombout(("internal fault: chaos in SSH 2 transport layer")); + crReturn(0); + } /* * Now we begin the fun. Generate and send e for Diffie-Hellman. @@ -1784,7 +2338,8 @@ static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt) crWaitUntil(ispkt); if (pktin.type != SSH2_MSG_KEXDH_REPLY) { - fatalbox("expected key exchange packet from server"); + bombout(("expected key exchange packet from server")); + crReturn(0); } ssh2_pkt_getstring(&hostkeydata, &hostkeylen); f = ssh2_pkt_getmp(); @@ -1805,24 +2360,34 @@ static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt) debug(("\r\n")); #endif - hostkey->setkey(hostkeydata, hostkeylen); - if (!hostkey->verifysig(sigdata, siglen, exchange_hash, 20)) - fatalbox("Server failed host key check"); + hkey = hostkey->newkey(hostkeydata, hostkeylen); + if (!hostkey->verifysig(hkey, sigdata, siglen, exchange_hash, 20)) { + bombout(("Server failed host key check")); + crReturn(0); + } /* * Expect SSH2_MSG_NEWKEYS from server. */ crWaitUntil(ispkt); - if (pktin.type != SSH2_MSG_NEWKEYS) - fatalbox("expected new-keys packet from server"); + if (pktin.type != SSH2_MSG_NEWKEYS) { + bombout(("expected new-keys packet from server")); + crReturn(0); + } /* * Authenticate remote host: verify host key. (We've already * checked the signature of the exchange hash.) */ - keystr = hostkey->fmtkey(); - verify_ssh_host_key(savedhost, keystr); - free(keystr); + keystr = hostkey->fmtkey(hkey); + fingerprint = hostkey->fingerprint(hkey); + verify_ssh_host_key(savedhost, savedport, hostkey->keytype, + keystr, fingerprint); + logevent("Host key fingerprint is:"); + logevent(fingerprint); + sfree(fingerprint); + sfree(keystr); + hostkey->freekey(hkey); /* * Send SSH2_MSG_NEWKEYS. @@ -1839,17 +2404,32 @@ static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt) scmac = scmac_tobe; cscomp = cscomp_tobe; sccomp = sccomp_tobe; + cscomp->compress_init(); + sccomp->decompress_init(); /* * Set IVs after keys. */ ssh2_mkkey(K, exchange_hash, 'C', keyspace); cscipher->setcskey(keyspace); - ssh2_mkkey(K, exchange_hash, 'D', keyspace); cscipher->setsckey(keyspace); + ssh2_mkkey(K, exchange_hash, 'D', keyspace); sccipher->setsckey(keyspace); ssh2_mkkey(K, exchange_hash, 'A', keyspace); cscipher->setcsiv(keyspace); ssh2_mkkey(K, exchange_hash, 'B', keyspace); sccipher->setsciv(keyspace); ssh2_mkkey(K, exchange_hash, 'E', keyspace); csmac->setcskey(keyspace); ssh2_mkkey(K, exchange_hash, 'F', keyspace); scmac->setsckey(keyspace); /* + * If this is the first key exchange phase, we must pass the + * SSH2_MSG_NEWKEYS packet to the next layer, not because it + * wants to see it but because it will need time to initialise + * itself before it sees an actual packet. In subsequent key + * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because + * it would only confuse the layer above. + */ + if (!first_kex) { + crReturn(0); + } + first_kex = 0; + + /* * Now we're encrypting. Begin returning 1 to the protocol main * function so that other things can run on top of the * transport. If we ever see a KEXINIT, we must go back to the @@ -1864,9 +2444,43 @@ static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt) } /* - * SSH2: remote identifier for the main session channel. + * Add data to an SSH2 channel output buffer. */ -static unsigned long ssh_remote_channel; +static void ssh2_add_channel_data(struct ssh_channel *c, char *buf, int len) { + if (c->v2.outbufsize < + c->v2.outbuflen + len) { + c->v2.outbufsize = + c->v2.outbuflen + len + 1024; + c->v2.outbuffer = srealloc(c->v2.outbuffer, + c->v2.outbufsize); + } + memcpy(c->v2.outbuffer + c->v2.outbuflen, + buf, len); + c->v2.outbuflen += len; +} + +/* + * Attempt to send data on an SSH2 channel. + */ +static void ssh2_try_send(struct ssh_channel *c) { + while (c->v2.remwindow > 0 && + c->v2.outbuflen > 0) { + unsigned len = c->v2.remwindow; + if (len > c->v2.outbuflen) + len = c->v2.outbuflen; + if (len > c->v2.remmaxpkt) + len = c->v2.remmaxpkt; + ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA); + ssh2_pkt_adduint32(c->remoteid); + ssh2_pkt_addstring_start(); + ssh2_pkt_addstring_data(c->v2.outbuffer, len); + ssh2_pkt_send(); + c->v2.outbuflen -= len; + memmove(c->v2.outbuffer, c->v2.outbuffer+len, + c->v2.outbuflen); + c->v2.remwindow -= len; + } +} /* * Handle the SSH2 userauth and connection layers. @@ -1885,8 +2499,10 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) ssh2_pkt_addstring("ssh-userauth"); ssh2_pkt_send(); crWaitUntilV(ispkt); - if (pktin.type != SSH2_MSG_SERVICE_ACCEPT) - fatalbox("Server refused user authentication protocol"); + if (pktin.type != SSH2_MSG_SERVICE_ACCEPT) { + bombout(("Server refused user authentication protocol")); + crReturnV; + } /* * FIXME: currently we support only password authentication. @@ -1902,8 +2518,9 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) static int pos = 0; static char c; - if ((flags & FLAG_CONNECTION) && !*cfg.username) { + if ((flags & FLAG_INTERACTIVE) && !*cfg.username) { c_write("login as: ", 10); + ssh_send_ok = 1; while (pos >= 0) { crWaitUntilV(!ispkt); while (inlen--) switch (c = *in++) { @@ -1942,15 +2559,15 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) char stuff[200]; strncpy(username, cfg.username, 99); username[99] = '\0'; - if (flags & FLAG_VERBOSE) { + if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) { sprintf(stuff, "Using username \"%s\".\r\n", username); c_write(stuff, strlen(stuff)); } } - if (!(flags & FLAG_WINDOWED)) { + if (ssh_get_password) { char prompt[200]; - sprintf(prompt, "%s@%s's password: ", cfg.username, savedhost); + sprintf(prompt, "%.90s@%.90s's password: ", username, savedhost); if (!ssh_get_password(prompt, password, sizeof(password))) { /* * get_password failed to get a password (for @@ -1964,6 +2581,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) } } else { c_write("password: ", 10); + ssh_send_ok = 1; pos = 0; while (pos >= 0) { @@ -2019,111 +2637,345 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) /* * So now create a channel with a session in it. */ + mainchan = smalloc(sizeof(struct ssh_channel)); + mainchan->localid = 100; /* as good as any */ ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN); ssh2_pkt_addstring("session"); - ssh2_pkt_adduint32(100); /* as good as any */ - ssh2_pkt_adduint32(0xFFFFFFFFUL); /* very big window which we ignore */ - ssh2_pkt_adduint32(0xFFFFFFFFUL); /* very big max pkt size */ + ssh2_pkt_adduint32(mainchan->localid); + ssh2_pkt_adduint32(0x8000UL); /* our window size */ + ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */ ssh2_pkt_send(); crWaitUntilV(ispkt); if (pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) { - fatalbox("Server refused to open a session"); + bombout(("Server refused to open a session")); + crReturnV; /* FIXME: error data comes back in FAILURE packet */ } - if (ssh2_pkt_getuint32() != 100) { - fatalbox("Server's channel confirmation cited wrong channel"); + if (ssh2_pkt_getuint32() != mainchan->localid) { + bombout(("Server's channel confirmation cited wrong channel")); + crReturnV; } - ssh_remote_channel = ssh2_pkt_getuint32(); - remote_winsize = ssh2_pkt_getuint32(); - remote_maxpkt = ssh2_pkt_getuint32(); + mainchan->remoteid = ssh2_pkt_getuint32(); + mainchan->type = CHAN_MAINSESSION; + mainchan->closes = 0; + mainchan->v2.remwindow = ssh2_pkt_getuint32(); + mainchan->v2.remmaxpkt = ssh2_pkt_getuint32(); + mainchan->v2.outbuffer = NULL; + mainchan->v2.outbuflen = mainchan->v2.outbufsize = 0; + ssh_channels = newtree234(ssh_channelcmp); + add234(ssh_channels, mainchan); logevent("Opened channel for session"); /* + * Potentially enable X11 forwarding. + */ + if (cfg.x11_forward) { + char proto[20], data[64]; + logevent("Requesting X11 forwarding"); + x11_invent_auth(proto, sizeof(proto), data, sizeof(data)); + ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST); + ssh2_pkt_adduint32(mainchan->remoteid); + ssh2_pkt_addstring("x11-req"); + ssh2_pkt_addbool(1); /* want reply */ + ssh2_pkt_addbool(0); /* many connections */ + ssh2_pkt_addstring(proto); + ssh2_pkt_addstring(data); + ssh2_pkt_adduint32(0); /* screen number */ + ssh2_pkt_send(); + + do { + crWaitUntilV(ispkt); + if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) { + unsigned i = ssh2_pkt_getuint32(); + struct ssh_channel *c; + c = find234(ssh_channels, &i, ssh_channelfind); + if (!c) + continue; /* nonexistent channel */ + c->v2.remwindow += ssh2_pkt_getuint32(); + } + } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST); + + if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) { + if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) { + bombout(("Server got confused by X11 forwarding request")); + crReturnV; + } + logevent("X11 forwarding refused"); + } else { + logevent("X11 forwarding enabled"); + ssh_X11_fwd_enabled = TRUE; + } + } + + /* * Now allocate a pty for the session. */ - ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST); - ssh2_pkt_adduint32(ssh_remote_channel); /* recipient channel */ - ssh2_pkt_addstring("pty-req"); - ssh2_pkt_addbool(1); /* want reply */ - ssh2_pkt_addstring(cfg.termtype); - ssh2_pkt_adduint32(cols); - ssh2_pkt_adduint32(rows); - ssh2_pkt_adduint32(0); /* pixel width */ - ssh2_pkt_adduint32(0); /* pixel height */ - ssh2_pkt_addstring_start(); - ssh2_pkt_addstring_data("\0", 1); /* TTY_OP_END, no special options */ - ssh2_pkt_send(); + if (!cfg.nopty) { + ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST); + ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */ + ssh2_pkt_addstring("pty-req"); + ssh2_pkt_addbool(1); /* want reply */ + ssh2_pkt_addstring(cfg.termtype); + ssh2_pkt_adduint32(cols); + ssh2_pkt_adduint32(rows); + ssh2_pkt_adduint32(0); /* pixel width */ + ssh2_pkt_adduint32(0); /* pixel height */ + ssh2_pkt_addstring_start(); + ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */ + ssh2_pkt_send(); + ssh_state = SSH_STATE_INTERMED; - do { /* FIXME: pay attention to these */ - crWaitUntilV(ispkt); - } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST); + do { + crWaitUntilV(ispkt); + if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) { + unsigned i = ssh2_pkt_getuint32(); + struct ssh_channel *c; + c = find234(ssh_channels, &i, ssh_channelfind); + if (!c) + continue; /* nonexistent channel */ + c->v2.remwindow += ssh2_pkt_getuint32(); + } + } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST); - if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) { - if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) { - fatalbox("Server got confused by pty request"); + if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) { + if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) { + bombout(("Server got confused by pty request")); + crReturnV; + } + c_write("Server refused to allocate pty\r\n", 32); + } else { + logevent("Allocated pty"); } - c_write("Server refused to allocate pty\r\n", 32); - } else { - logevent("Allocated pty"); } /* - * Start a shell. + * Start a shell or a remote command. */ ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST); - ssh2_pkt_adduint32(ssh_remote_channel); /* recipient channel */ - ssh2_pkt_addstring("shell"); - ssh2_pkt_addbool(1); /* want reply */ + ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */ + if (*cfg.remote_cmd) { + ssh2_pkt_addstring("exec"); + ssh2_pkt_addbool(1); /* want reply */ + ssh2_pkt_addstring(cfg.remote_cmd); + } else { + ssh2_pkt_addstring("shell"); + ssh2_pkt_addbool(1); /* want reply */ + } ssh2_pkt_send(); - do { /* FIXME: pay attention to these */ + do { crWaitUntilV(ispkt); + if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) { + unsigned i = ssh2_pkt_getuint32(); + struct ssh_channel *c; + c = find234(ssh_channels, &i, ssh_channelfind); + if (!c) + continue; /* nonexistent channel */ + c->v2.remwindow += ssh2_pkt_getuint32(); + } } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST); if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) { if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) { - fatalbox("Server got confused by shell request"); + bombout(("Server got confused by shell/command request")); + crReturnV; } - fatalbox("Server refused to start a shell"); + bombout(("Server refused to start a shell/command")); + crReturnV; } else { - logevent("Started a shell"); + logevent("Started a shell/command"); } + ssh_state = SSH_STATE_SESSION; + if (size_needed) + ssh_size(); + if (eof_needed) + ssh_special(TS_EOF); + /* * Transfer data! */ ssh_send_ok = 1; + begin_session(); while (1) { + static int try_send; crReturnV; + try_send = FALSE; if (ispkt) { if (pktin.type == SSH2_MSG_CHANNEL_DATA || pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) { char *data; int length; - if (ssh2_pkt_getuint32() != 100) - continue; /* wrong channel */ + unsigned i = ssh2_pkt_getuint32(); + struct ssh_channel *c; + c = find234(ssh_channels, &i, ssh_channelfind); + if (!c) + continue; /* nonexistent channel */ if (pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA && ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR) continue; /* extended but not stderr */ ssh2_pkt_getstring(&data, &length); - if (data) - c_write(data, length); + if (data) { + switch (c->type) { + case CHAN_MAINSESSION: + from_backend(pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA, + data, length); + break; + case CHAN_X11: + x11_send(c->u.x11.s, data, length); + break; + } + /* + * Enlarge the window again at the remote + * side, just in case it ever runs down and + * they fail to send us any more data. + */ + ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST); + ssh2_pkt_adduint32(c->remoteid); + ssh2_pkt_adduint32(length); + ssh2_pkt_send(); + } } else if (pktin.type == SSH2_MSG_DISCONNECT) { ssh_state = SSH_STATE_CLOSED; - logevent("Received disconnect request"); + logevent("Received disconnect message"); + crReturnV; } else if (pktin.type == SSH2_MSG_CHANNEL_REQUEST) { continue; /* exit status et al; ignore (FIXME?) */ + } else if (pktin.type == SSH2_MSG_CHANNEL_EOF) { + unsigned i = ssh2_pkt_getuint32(); + struct ssh_channel *c; + + c = find234(ssh_channels, &i, ssh_channelfind); + if (!c) + continue; /* nonexistent channel */ + + if (c->type == CHAN_X11) { + /* + * Remote EOF on an X11 channel means we should + * wrap up and close the channel ourselves. + */ + x11_close(c->u.x11.s); + sshfwd_close(c); + } + } else if (pktin.type == SSH2_MSG_CHANNEL_CLOSE) { + unsigned i = ssh2_pkt_getuint32(); + struct ssh_channel *c; + enum234 e; + + c = find234(ssh_channels, &i, ssh_channelfind); + if (!c) + continue; /* nonexistent channel */ + if (c->closes == 0) { + ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE); + ssh2_pkt_adduint32(c->remoteid); + ssh2_pkt_send(); + } + /* Do pre-close processing on the channel. */ + switch (c->type) { + case CHAN_MAINSESSION: + break; /* nothing to see here, move along */ + case CHAN_X11: + break; + } + del234(ssh_channels, c); + sfree(c->v2.outbuffer); + sfree(c); + + /* + * See if that was the last channel left open. + */ + c = first234(ssh_channels, &e); + if (!c) { + logevent("All channels closed. Disconnecting"); + ssh2_pkt_init(SSH2_MSG_DISCONNECT); + ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION); + ssh2_pkt_addstring("All open channels closed"); + ssh2_pkt_addstring("en"); /* language tag */ + ssh2_pkt_send(); + ssh_state = SSH_STATE_CLOSED; + crReturnV; + } + continue; /* remote sends close; ignore (FIXME) */ } else if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) { - continue; /* ignore for now (FIXME!) */ + unsigned i = ssh2_pkt_getuint32(); + struct ssh_channel *c; + c = find234(ssh_channels, &i, ssh_channelfind); + if (!c) + continue; /* nonexistent channel */ + mainchan->v2.remwindow += ssh2_pkt_getuint32(); + try_send = TRUE; + } else if (pktin.type == SSH2_MSG_CHANNEL_OPEN) { + char *type; + int typelen; + char *error = NULL; + struct ssh_channel *c; + ssh2_pkt_getstring(&type, &typelen); + c = smalloc(sizeof(struct ssh_channel)); + + if (typelen == 3 && !memcmp(type, "x11", 3)) { + if (!ssh_X11_fwd_enabled) + error = "X11 forwarding is not enabled"; + else if ( x11_init(&c->u.x11.s, cfg.x11_display, c) != NULL ) { + error = "Unable to open an X11 connection"; + } else { + c->type = CHAN_X11; + } + } else { + error = "Unsupported channel type requested"; + } + + c->remoteid = ssh2_pkt_getuint32(); + if (error) { + ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE); + ssh2_pkt_adduint32(c->remoteid); + ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED); + ssh2_pkt_addstring(error); + ssh2_pkt_addstring("en"); /* language tag */ + ssh2_pkt_send(); + sfree(c); + } else { + struct ssh_channel *d; + unsigned i; + enum234 e; + + for (i=1, d = first234(ssh_channels, &e); d; + d = next234(&e)) { + if (d->localid > i) + break; /* found a free number */ + i = d->localid + 1; + } + c->localid = i; + c->closes = 0; + c->v2.remwindow = ssh2_pkt_getuint32(); + c->v2.remmaxpkt = ssh2_pkt_getuint32(); + c->v2.outbuffer = NULL; + c->v2.outbuflen = c->v2.outbufsize = 0; + add234(ssh_channels, c); + ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); + ssh2_pkt_adduint32(c->remoteid); + ssh2_pkt_adduint32(c->localid); + ssh2_pkt_adduint32(0x8000UL); /* our window size */ + ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */ + ssh2_pkt_send(); + } } else { - fatalbox("Strange packet received: type %d", pktin.type); + bombout(("Strange packet received: type %d", pktin.type)); + crReturnV; } } else { - /* FIXME: for now, ignore window size */ - ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA); - ssh2_pkt_adduint32(ssh_remote_channel); - ssh2_pkt_addstring_start(); - ssh2_pkt_addstring_data(in, inlen); - ssh2_pkt_send(); + /* + * We have spare data. Add it to the channel buffer. + */ + ssh2_add_channel_data(mainchan, in, inlen); + try_send = TRUE; } + if (try_send) { + enum234 e; + struct ssh_channel *c; + /* + * Try to send data on all channels if we can. + */ + for (c = first234(ssh_channels, &e); c; c = next234(&e)) + ssh2_try_send(c); + } } crFinishV; @@ -2140,13 +2992,11 @@ static void ssh2_protocol(unsigned char *in, int inlen, int ispkt) } /* - * Called to set up the connection. Will arrange for WM_NETEVENT - * messages to be passed to the specified window, whose window - * procedure should then call telnet_msg(). + * Called to set up the connection. * * Returns an error message, or NULL on success. */ -static char *ssh_init (HWND hwnd, char *host, int port, char **realhost) { +static char *ssh_init (char *host, int port, char **realhost) { char *p; #ifdef MSCRYPTOAPI @@ -2154,82 +3004,32 @@ static char *ssh_init (HWND hwnd, char *host, int port, char **realhost) { return "Microsoft high encryption pack not installed!"; #endif + ssh_send_ok = 0; + p = connect_to_host(host, port, realhost); if (p != NULL) return p; - if (!do_ssh_init()) - return "Protocol initialisation error"; - - if (hwnd && WSAAsyncSelect (s, hwnd, WM_NETEVENT, FD_READ | FD_CLOSE) == SOCKET_ERROR) - switch (WSAGetLastError()) { - case WSAENETDOWN: return "Network is down"; - default: return "WSAAsyncSelect(): unknown error"; - } - return NULL; } /* - * Process a WM_NETEVENT message. Will return 0 if the connection - * has closed, or <0 for a socket error. - */ -static int ssh_msg (WPARAM wParam, LPARAM lParam) { - int ret; - char buf[256]; - - /* - * Because reading less than the whole of the available pending - * data can generate an FD_READ event, we need to allow for the - * possibility that FD_READ may arrive with FD_CLOSE already in - * the queue; so it's possible that we can get here even with s - * invalid. If so, we return 1 and don't worry about it. - */ - if (s == INVALID_SOCKET) - return 1; - - if (WSAGETSELECTERROR(lParam) != 0) - return -WSAGETSELECTERROR(lParam); - - switch (WSAGETSELECTEVENT(lParam)) { - case FD_READ: - case FD_CLOSE: - ret = recv(s, buf, sizeof(buf), 0); - if (ret < 0 && WSAGetLastError() == WSAEWOULDBLOCK) - return 1; - if (ret < 0) /* any _other_ error */ - return -10000-WSAGetLastError(); - if (ret == 0) { - s = INVALID_SOCKET; - return 0; - } - ssh_gotdata (buf, ret); - if (ssh_state == SSH_STATE_CLOSED) { - closesocket(s); - s = INVALID_SOCKET; - return 0; - } - return 1; - } - return 1; /* shouldn't happen, but WTF */ -} - -/* * Called to send data down the Telnet connection. */ static void ssh_send (char *buf, int len) { - if (s == INVALID_SOCKET) + if (s == NULL || ssh_protocol == NULL) return; ssh_protocol(buf, len, 0); } /* - * Called to set the size of the window from Telnet's POV. + * Called to set the size of the window from SSH's POV. */ static void ssh_size(void) { switch (ssh_state) { case SSH_STATE_BEFORE_SIZE: + case SSH_STATE_PREPACKET: case SSH_STATE_CLOSED: break; /* do nothing */ case SSH_STATE_INTERMED: @@ -2237,10 +3037,23 @@ static void ssh_size(void) { break; case SSH_STATE_SESSION: if (!cfg.nopty) { - send_packet(SSH1_CMSG_WINDOW_SIZE, - PKT_INT, rows, PKT_INT, cols, - PKT_INT, 0, PKT_INT, 0, PKT_END); + if (ssh_version == 1) { + send_packet(SSH1_CMSG_WINDOW_SIZE, + PKT_INT, rows, PKT_INT, cols, + PKT_INT, 0, PKT_INT, 0, PKT_END); + } else { + ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST); + ssh2_pkt_adduint32(mainchan->remoteid); + ssh2_pkt_addstring("window-change"); + ssh2_pkt_addbool(0); + ssh2_pkt_adduint32(cols); + ssh2_pkt_adduint32(rows); + ssh2_pkt_adduint32(0); + ssh2_pkt_adduint32(0); + ssh2_pkt_send(); + } } + break; } } @@ -2251,11 +3064,31 @@ static void ssh_size(void) { */ static void ssh_special (Telnet_Special code) { if (code == TS_EOF) { - if (ssh_version = 1) { + if (ssh_state != SSH_STATE_SESSION) { + /* + * Buffer the EOF in case we are pre-SESSION, so we can + * send it as soon as we reach SESSION. + */ + if (code == TS_EOF) + eof_needed = TRUE; + return; + } + if (ssh_version == 1) { send_packet(SSH1_CMSG_EOF, PKT_END); } else { ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF); - ssh2_pkt_adduint32(ssh_remote_channel); + ssh2_pkt_adduint32(mainchan->remoteid); + ssh2_pkt_send(); + } + logevent("Sent EOF message"); + } else if (code == TS_PING) { + if (ssh_state == SSH_STATE_CLOSED || ssh_state == SSH_STATE_PREPACKET) + return; + if (ssh_version == 1) { + send_packet(SSH1_MSG_IGNORE, PKT_STR, "", PKT_END); + } else { + ssh2_pkt_init(SSH2_MSG_IGNORE); + ssh2_pkt_addstring_start(); ssh2_pkt_send(); } } else { @@ -2263,180 +3096,16 @@ static void ssh_special (Telnet_Special code) { } } - -/* - * Read and decrypt one incoming SSH packet. - * (only used by pSCP) - */ -static void get_packet(void) -{ - unsigned char buf[4096], *p; - long to_read; - int len; - - p = NULL; - len = 0; - - while ((to_read = s_rdpkt(&p, &len)) > 0) { - if (to_read > sizeof(buf)) to_read = sizeof(buf); - len = s_read(buf, to_read); - if (len != to_read) { - closesocket(s); - s = INVALID_SOCKET; - return; - } - p = buf; - } - - assert(len == 0); -} - -/* - * Receive a block of data over the SSH link. Block until - * all data is available. Return nr of bytes read (0 if lost connection). - * (only used by pSCP) - */ -int ssh_scp_recv(unsigned char *buf, int len) -{ - static int pending_input_len = 0; - static unsigned char *pending_input_ptr; - int to_read = len; - - if (pending_input_len >= to_read) { - memcpy(buf, pending_input_ptr, to_read); - pending_input_ptr += to_read; - pending_input_len -= to_read; - return len; - } - - if (pending_input_len > 0) { - memcpy(buf, pending_input_ptr, pending_input_len); - buf += pending_input_len; - to_read -= pending_input_len; - pending_input_len = 0; - } - - if (s == INVALID_SOCKET) - return 0; - while (to_read > 0) { - get_packet(); - if (s == INVALID_SOCKET) - return 0; - if (pktin.type == SSH1_SMSG_STDOUT_DATA) { - int plen = GET_32BIT(pktin.body); - if (plen <= to_read) { - memcpy(buf, pktin.body + 4, plen); - buf += plen; - to_read -= plen; - } else { - memcpy(buf, pktin.body + 4, to_read); - pending_input_len = plen - to_read; - pending_input_ptr = pktin.body + 4 + to_read; - to_read = 0; - } - } else if (pktin.type == SSH1_SMSG_STDERR_DATA) { - int plen = GET_32BIT(pktin.body); - fwrite(pktin.body + 4, plen, 1, stderr); - } else if (pktin.type == SSH1_MSG_DISCONNECT) { - logevent("Received disconnect request"); - } else if (pktin.type == SSH1_SMSG_SUCCESS || - pktin.type == SSH1_SMSG_FAILURE) { - /* ignore */ - } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) { - char logbuf[100]; - sprintf(logbuf, "Remote exit status: %d", GET_32BIT(pktin.body)); - logevent(logbuf); - send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END); - logevent("Closing connection"); - closesocket(s); - s = INVALID_SOCKET; - } else { - fatalbox("Strange packet received: type %d", pktin.type); - } - } - - return len; -} - -/* - * Send a block of data over the SSH link. - * Block until all data is sent. - * (only used by pSCP) - */ -void ssh_scp_send(unsigned char *buf, int len) -{ - if (s == INVALID_SOCKET) - return; - send_packet(SSH1_CMSG_STDIN_DATA, - PKT_INT, len, PKT_DATA, buf, len, PKT_END); -} - -/* - * Send an EOF notification to the server. - * (only used by pSCP) - */ -void ssh_scp_send_eof(void) -{ - if (s == INVALID_SOCKET) - return; - send_packet(SSH1_CMSG_EOF, PKT_END); -} - -/* - * Set up the connection, login on the remote host and - * start execution of a command. - * Returns an error message, or NULL on success. - * (only used by pSCP) - */ -char *ssh_scp_init(char *host, int port, char *cmd, char **realhost) -{ - char buf[160], *p; - -#ifdef MSCRYPTOAPI - if (crypto_startup() == 0) - return "Microsoft high encryption pack not installed!"; -#endif - - p = connect_to_host(host, port, realhost); - if (p != NULL) - return p; - - random_init(); - - if (!do_ssh_init()) - return "Protocol initialisation error"; - - /* Exchange keys and login */ - do { - get_packet(); - if (s == INVALID_SOCKET) - return "Connection closed by remote host"; - } while (!do_ssh1_login(NULL, 0, 1)); - - if (ssh_state == SSH_STATE_CLOSED) { - closesocket(s); - s = INVALID_SOCKET; - return "Session initialisation error"; - } - - /* Execute command */ - sprintf(buf, "Sending command: %.100s", cmd); - logevent(buf); - send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END); - - return NULL; -} - -static SOCKET ssh_socket(void) { return s; } +static Socket ssh_socket(void) { return s; } static int ssh_sendok(void) { return ssh_send_ok; } Backend ssh_backend = { ssh_init, - ssh_msg, ssh_send, ssh_size, ssh_special, ssh_socket, - ssh_sendok + ssh_sendok, + 22 };