ff2ae367 |
1 | /* |
2 | * console.c: various interactive-prompt routines shared between |
3 | * the console PuTTY tools |
4 | */ |
5 | |
6 | #include <windows.h> |
7 | |
8 | #include <stdio.h> |
9 | #include <stdlib.h> |
10 | #include <stdarg.h> |
11 | |
12 | #include "putty.h" |
13 | #include "storage.h" |
14 | #include "ssh.h" |
15 | |
16 | int console_batch_mode = FALSE; |
17 | |
18 | void verify_ssh_host_key(char *host, int port, char *keytype, |
19 | char *keystr, char *fingerprint) |
20 | { |
21 | int ret; |
22 | HANDLE hin; |
23 | DWORD savemode, i; |
24 | |
25 | static const char absentmsg_batch[] = |
26 | "The server's host key is not cached in the registry. You\n" |
27 | "have no guarantee that the server is the computer you\n" |
28 | "think it is.\n" |
29 | "The server's key fingerprint is:\n" |
30 | "%s\n" |
31 | "Connection abandoned.\n"; |
32 | static const char absentmsg[] = |
33 | "The server's host key is not cached in the registry. You\n" |
34 | "have no guarantee that the server is the computer you\n" |
35 | "think it is.\n" |
36 | "The server's key fingerprint is:\n" |
37 | "%s\n" |
38 | "If you trust this host, enter \"y\" to add the key to\n" |
39 | "PuTTY's cache and carry on connecting.\n" |
40 | "If you want to carry on connecting just once, without\n" |
41 | "adding the key to the cache, enter \"n\".\n" |
42 | "If you do not trust this host, press Return to abandon the\n" |
43 | "connection.\n" |
44 | "Store key in cache? (y/n) "; |
45 | |
46 | static const char wrongmsg_batch[] = |
47 | "WARNING - POTENTIAL SECURITY BREACH!\n" |
48 | "The server's host key does not match the one PuTTY has\n" |
49 | "cached in the registry. This means that either the\n" |
50 | "server administrator has changed the host key, or you\n" |
51 | "have actually connected to another computer pretending\n" |
52 | "to be the server.\n" |
53 | "The new key fingerprint is:\n" |
54 | "%s\n" |
55 | "Connection abandoned.\n"; |
56 | static const char wrongmsg[] = |
57 | "WARNING - POTENTIAL SECURITY BREACH!\n" |
58 | "The server's host key does not match the one PuTTY has\n" |
59 | "cached in the registry. This means that either the\n" |
60 | "server administrator has changed the host key, or you\n" |
61 | "have actually connected to another computer pretending\n" |
62 | "to be the server.\n" |
63 | "The new key fingerprint is:\n" |
64 | "%s\n" |
65 | "If you were expecting this change and trust the new key,\n" |
66 | "enter \"y\" to update PuTTY's cache and continue connecting.\n" |
67 | "If you want to carry on connecting but without updating\n" |
68 | "the cache, enter \"n\".\n" |
69 | "If you want to abandon the connection completely, press\n" |
70 | "Return to cancel. Pressing Return is the ONLY guaranteed\n" |
71 | "safe choice.\n" |
72 | "Update cached key? (y/n, Return cancels connection) "; |
73 | |
74 | static const char abandoned[] = "Connection abandoned.\n"; |
75 | |
76 | char line[32]; |
77 | |
78 | /* |
79 | * Verify the key against the registry. |
80 | */ |
81 | ret = verify_host_key(host, port, keytype, keystr); |
82 | |
83 | if (ret == 0) /* success - key matched OK */ |
84 | return; |
85 | |
86 | if (ret == 2) { /* key was different */ |
87 | if (console_batch_mode) { |
88 | fprintf(stderr, wrongmsg_batch, fingerprint); |
89 | exit(1); |
90 | } |
91 | fprintf(stderr, wrongmsg, fingerprint); |
92 | fflush(stderr); |
93 | } |
94 | if (ret == 1) { /* key was absent */ |
95 | if (console_batch_mode) { |
96 | fprintf(stderr, absentmsg_batch, fingerprint); |
97 | exit(1); |
98 | } |
99 | fprintf(stderr, absentmsg, fingerprint); |
100 | fflush(stderr); |
101 | } |
102 | |
103 | hin = GetStdHandle(STD_INPUT_HANDLE); |
104 | GetConsoleMode(hin, &savemode); |
105 | SetConsoleMode(hin, (savemode | ENABLE_ECHO_INPUT | |
106 | ENABLE_PROCESSED_INPUT | ENABLE_LINE_INPUT)); |
107 | ReadFile(hin, line, sizeof(line) - 1, &i, NULL); |
108 | SetConsoleMode(hin, savemode); |
109 | |
110 | if (line[0] != '\0' && line[0] != '\r' && line[0] != '\n') { |
111 | if (line[0] == 'y' || line[0] == 'Y') |
112 | store_host_key(host, port, keytype, keystr); |
113 | } else { |
114 | fprintf(stderr, abandoned); |
115 | exit(0); |
116 | } |
117 | } |
118 | |
119 | /* |
120 | * Ask whether the selected cipher is acceptable (since it was |
121 | * below the configured 'warn' threshold). |
122 | * cs: 0 = both ways, 1 = client->server, 2 = server->client |
123 | */ |
124 | void askcipher(char *ciphername, int cs) |
125 | { |
126 | HANDLE hin; |
127 | DWORD savemode, i; |
128 | |
129 | static const char msg[] = |
130 | "The first %scipher supported by the server is\n" |
131 | "%s, which is below the configured warning threshold.\n" |
132 | "Continue with connection? (y/n) "; |
133 | static const char msg_batch[] = |
134 | "The first %scipher supported by the server is\n" |
135 | "%s, which is below the configured warning threshold.\n" |
136 | "Connection abandoned.\n"; |
137 | static const char abandoned[] = "Connection abandoned.\n"; |
138 | |
139 | char line[32]; |
140 | |
141 | if (console_batch_mode) { |
142 | fprintf(stderr, msg_batch, |
143 | (cs == 0) ? "" : |
144 | (cs == 1) ? "client-to-server " : "server-to-client ", |
145 | ciphername); |
146 | exit(1); |
147 | } |
148 | |
149 | fprintf(stderr, msg, |
150 | (cs == 0) ? "" : |
151 | (cs == 1) ? "client-to-server " : "server-to-client ", |
152 | ciphername); |
153 | fflush(stderr); |
154 | |
155 | hin = GetStdHandle(STD_INPUT_HANDLE); |
156 | GetConsoleMode(hin, &savemode); |
157 | SetConsoleMode(hin, (savemode | ENABLE_ECHO_INPUT | |
158 | ENABLE_PROCESSED_INPUT | ENABLE_LINE_INPUT)); |
159 | ReadFile(hin, line, sizeof(line) - 1, &i, NULL); |
160 | SetConsoleMode(hin, savemode); |
161 | |
162 | if (line[0] == 'y' || line[0] == 'Y') { |
163 | return; |
164 | } else { |
165 | fprintf(stderr, abandoned); |
166 | exit(0); |
167 | } |
168 | } |
169 | |
170 | /* |
171 | * Ask whether to wipe a session log file before writing to it. |
172 | * Returns 2 for wipe, 1 for append, 0 for cancel (don't log). |
173 | */ |
174 | int askappend(char *filename) |
175 | { |
176 | HANDLE hin; |
177 | DWORD savemode, i; |
178 | |
179 | static const char msgtemplate[] = |
180 | "The session log file \"%.*s\" already exists.\n" |
181 | "You can overwrite it with a new session log,\n" |
182 | "append your session log to the end of it,\n" |
183 | "or disable session logging for this session.\n" |
184 | "Enter \"y\" to wipe the file, \"n\" to append to it,\n" |
185 | "or just press Return to disable logging.\n" |
186 | "Wipe the log file? (y/n, Return cancels logging) "; |
187 | |
188 | static const char msgtemplate_batch[] = |
189 | "The session log file \"%.*s\" already exists.\n" |
190 | "Logging will not be enabled.\n"; |
191 | |
192 | char line[32]; |
193 | |
194 | if (console_batch_mode) { |
195 | fprintf(stderr, msgtemplate_batch, FILENAME_MAX, filename); |
196 | fflush(stderr); |
197 | return 0; |
198 | } |
199 | fprintf(stderr, msgtemplate, FILENAME_MAX, filename); |
200 | fflush(stderr); |
201 | |
202 | hin = GetStdHandle(STD_INPUT_HANDLE); |
203 | GetConsoleMode(hin, &savemode); |
204 | SetConsoleMode(hin, (savemode | ENABLE_ECHO_INPUT | |
205 | ENABLE_PROCESSED_INPUT | ENABLE_LINE_INPUT)); |
206 | ReadFile(hin, line, sizeof(line) - 1, &i, NULL); |
207 | SetConsoleMode(hin, savemode); |
208 | |
209 | if (line[0] == 'y' || line[0] == 'Y') |
210 | return 2; |
211 | else if (line[0] == 'n' || line[0] == 'N') |
212 | return 1; |
213 | else |
214 | return 0; |
215 | } |
216 | |
217 | /* |
218 | * Warn about the obsolescent key file format. |
219 | */ |
220 | void old_keyfile_warning(void) |
221 | { |
222 | static const char message[] = |
223 | "You are loading an SSH 2 private key which has an\n" |
224 | "old version of the file format. This means your key\n" |
225 | "file is not fully tamperproof. Future versions of\n" |
226 | "PuTTY may stop supporting this private key format,\n" |
227 | "so we recommend you convert your key to the new\n" |
228 | "format.\n" |
229 | "\n" |
230 | "Once the key is loaded into PuTTYgen, you can perform\n" |
231 | "this conversion simply by saving it again.\n"; |
232 | |
233 | fputs(message, stderr); |
234 | } |
235 | |
236 | void logevent(char *string) |
237 | { |
238 | } |
239 | |
240 | char *console_password = NULL; |
241 | |
242 | int console_get_line(const char *prompt, char *str, |
243 | int maxlen, int is_pw) |
244 | { |
245 | HANDLE hin, hout; |
246 | DWORD savemode, newmode, i; |
247 | |
248 | if (is_pw && console_password) { |
249 | static int tried_once = 0; |
250 | |
251 | if (tried_once) { |
252 | return 0; |
253 | } else { |
254 | strncpy(str, console_password, maxlen); |
255 | str[maxlen - 1] = '\0'; |
256 | tried_once = 1; |
257 | return 1; |
258 | } |
259 | } |
260 | |
261 | if (console_batch_mode) { |
262 | if (maxlen > 0) |
263 | str[0] = '\0'; |
264 | } else { |
265 | hin = GetStdHandle(STD_INPUT_HANDLE); |
266 | hout = GetStdHandle(STD_OUTPUT_HANDLE); |
267 | if (hin == INVALID_HANDLE_VALUE || hout == INVALID_HANDLE_VALUE) { |
268 | fprintf(stderr, "Cannot get standard input/output handles\n"); |
269 | exit(1); |
270 | } |
271 | |
272 | GetConsoleMode(hin, &savemode); |
273 | newmode = savemode | ENABLE_PROCESSED_INPUT | ENABLE_LINE_INPUT; |
274 | if (is_pw) |
275 | newmode &= ~ENABLE_ECHO_INPUT; |
276 | else |
277 | newmode |= ENABLE_ECHO_INPUT; |
278 | SetConsoleMode(hin, newmode); |
279 | |
280 | WriteFile(hout, prompt, strlen(prompt), &i, NULL); |
281 | ReadFile(hin, str, maxlen - 1, &i, NULL); |
282 | |
283 | SetConsoleMode(hin, savemode); |
284 | |
285 | if ((int) i > maxlen) |
286 | i = maxlen - 1; |
287 | else |
288 | i = i - 2; |
289 | str[i] = '\0'; |
290 | |
291 | if (is_pw) |
292 | WriteFile(hout, "\r\n", 2, &i, NULL); |
293 | |
294 | } |
295 | return 1; |
296 | } |