]>
Commit | Line | Data |
---|---|---|
2e437378 | 1 | /* $OpenBSD: auth-options.c,v 1.40 2006/08/03 03:34:41 deraadt Exp $ */ |
3c0ef626 | 2 | /* |
3 | * Author: Tatu Ylonen <ylo@cs.hut.fi> | |
4 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland | |
5 | * All rights reserved | |
6 | * As far as I am concerned, the code I have written for this software | |
7 | * can be used freely for any purpose. Any derived versions of this | |
8 | * software must be clearly marked as such, and if the derived work is | |
9 | * incompatible with the protocol description in the RFC file, it must be | |
10 | * called by a name other than "ssh" or "Secure Shell". | |
11 | */ | |
12 | ||
13 | #include "includes.h" | |
2e437378 | 14 | |
15 | #include <sys/types.h> | |
16 | ||
17 | #include <netdb.h> | |
18 | #include <pwd.h> | |
19 | #include <string.h> | |
20 | #include <stdio.h> | |
21 | #include <stdarg.h> | |
3c0ef626 | 22 | |
3c0ef626 | 23 | #include "xmalloc.h" |
24 | #include "match.h" | |
25 | #include "log.h" | |
26 | #include "canohost.h" | |
2e437378 | 27 | #include "buffer.h" |
3c0ef626 | 28 | #include "channels.h" |
29 | #include "auth-options.h" | |
30 | #include "servconf.h" | |
31 | #include "misc.h" | |
2e437378 | 32 | #include "key.h" |
33 | #include "hostfile.h" | |
2980ea68 | 34 | #include "auth.h" |
2e437378 | 35 | #ifdef GSSAPI |
36 | #include "ssh-gss.h" | |
37 | #endif | |
38 | #include "monitor_wrap.h" | |
3c0ef626 | 39 | |
40 | /* Flags set authorized_keys flags */ | |
41 | int no_port_forwarding_flag = 0; | |
42 | int no_agent_forwarding_flag = 0; | |
43 | int no_x11_forwarding_flag = 0; | |
44 | int no_pty_flag = 0; | |
45 | ||
46 | /* "command=" option. */ | |
47 | char *forced_command = NULL; | |
48 | ||
49 | /* "environment=" options. */ | |
50 | struct envstring *custom_environment = NULL; | |
51 | ||
e00da40d | 52 | /* "tunnel=" option. */ |
53 | int forced_tun_device = -1; | |
54 | ||
3c0ef626 | 55 | extern ServerOptions options; |
56 | ||
57 | void | |
58 | auth_clear_options(void) | |
59 | { | |
60 | no_agent_forwarding_flag = 0; | |
61 | no_port_forwarding_flag = 0; | |
62 | no_pty_flag = 0; | |
63 | no_x11_forwarding_flag = 0; | |
64 | while (custom_environment) { | |
65 | struct envstring *ce = custom_environment; | |
66 | custom_environment = ce->next; | |
67 | xfree(ce->s); | |
68 | xfree(ce); | |
69 | } | |
70 | if (forced_command) { | |
71 | xfree(forced_command); | |
72 | forced_command = NULL; | |
73 | } | |
e00da40d | 74 | forced_tun_device = -1; |
3c0ef626 | 75 | channel_clear_permitted_opens(); |
2980ea68 | 76 | auth_debug_reset(); |
3c0ef626 | 77 | } |
78 | ||
79 | /* | |
80 | * return 1 if access is granted, 0 if not. | |
81 | * side effect: sets key option flags | |
82 | */ | |
83 | int | |
84 | auth_parse_options(struct passwd *pw, char *opts, char *file, u_long linenum) | |
85 | { | |
86 | const char *cp; | |
87 | int i; | |
88 | ||
89 | /* reset options */ | |
90 | auth_clear_options(); | |
91 | ||
92 | if (!opts) | |
93 | return 1; | |
94 | ||
95 | while (*opts && *opts != ' ' && *opts != '\t') { | |
96 | cp = "no-port-forwarding"; | |
97 | if (strncasecmp(opts, cp, strlen(cp)) == 0) { | |
2980ea68 | 98 | auth_debug_add("Port forwarding disabled."); |
3c0ef626 | 99 | no_port_forwarding_flag = 1; |
100 | opts += strlen(cp); | |
101 | goto next_option; | |
102 | } | |
103 | cp = "no-agent-forwarding"; | |
104 | if (strncasecmp(opts, cp, strlen(cp)) == 0) { | |
2980ea68 | 105 | auth_debug_add("Agent forwarding disabled."); |
3c0ef626 | 106 | no_agent_forwarding_flag = 1; |
107 | opts += strlen(cp); | |
108 | goto next_option; | |
109 | } | |
110 | cp = "no-X11-forwarding"; | |
111 | if (strncasecmp(opts, cp, strlen(cp)) == 0) { | |
2980ea68 | 112 | auth_debug_add("X11 forwarding disabled."); |
3c0ef626 | 113 | no_x11_forwarding_flag = 1; |
114 | opts += strlen(cp); | |
115 | goto next_option; | |
116 | } | |
117 | cp = "no-pty"; | |
118 | if (strncasecmp(opts, cp, strlen(cp)) == 0) { | |
2980ea68 | 119 | auth_debug_add("Pty allocation disabled."); |
3c0ef626 | 120 | no_pty_flag = 1; |
121 | opts += strlen(cp); | |
122 | goto next_option; | |
123 | } | |
124 | cp = "command=\""; | |
125 | if (strncasecmp(opts, cp, strlen(cp)) == 0) { | |
126 | opts += strlen(cp); | |
127 | forced_command = xmalloc(strlen(opts) + 1); | |
128 | i = 0; | |
129 | while (*opts) { | |
130 | if (*opts == '"') | |
131 | break; | |
132 | if (*opts == '\\' && opts[1] == '"') { | |
133 | opts += 2; | |
134 | forced_command[i++] = '"'; | |
135 | continue; | |
136 | } | |
137 | forced_command[i++] = *opts++; | |
138 | } | |
139 | if (!*opts) { | |
140 | debug("%.100s, line %lu: missing end quote", | |
141 | file, linenum); | |
2980ea68 | 142 | auth_debug_add("%.100s, line %lu: missing end quote", |
3c0ef626 | 143 | file, linenum); |
144 | xfree(forced_command); | |
145 | forced_command = NULL; | |
146 | goto bad_option; | |
147 | } | |
2e437378 | 148 | forced_command[i] = '\0'; |
2980ea68 | 149 | auth_debug_add("Forced command: %.900s", forced_command); |
3c0ef626 | 150 | opts++; |
151 | goto next_option; | |
152 | } | |
153 | cp = "environment=\""; | |
e54b3d7c | 154 | if (options.permit_user_env && |
155 | strncasecmp(opts, cp, strlen(cp)) == 0) { | |
3c0ef626 | 156 | char *s; |
157 | struct envstring *new_envstring; | |
158 | ||
159 | opts += strlen(cp); | |
160 | s = xmalloc(strlen(opts) + 1); | |
161 | i = 0; | |
162 | while (*opts) { | |
163 | if (*opts == '"') | |
164 | break; | |
165 | if (*opts == '\\' && opts[1] == '"') { | |
166 | opts += 2; | |
167 | s[i++] = '"'; | |
168 | continue; | |
169 | } | |
170 | s[i++] = *opts++; | |
171 | } | |
172 | if (!*opts) { | |
173 | debug("%.100s, line %lu: missing end quote", | |
174 | file, linenum); | |
2980ea68 | 175 | auth_debug_add("%.100s, line %lu: missing end quote", |
3c0ef626 | 176 | file, linenum); |
177 | xfree(s); | |
178 | goto bad_option; | |
179 | } | |
2e437378 | 180 | s[i] = '\0'; |
2980ea68 | 181 | auth_debug_add("Adding to environment: %.900s", s); |
3c0ef626 | 182 | debug("Adding to environment: %.900s", s); |
183 | opts++; | |
184 | new_envstring = xmalloc(sizeof(struct envstring)); | |
185 | new_envstring->s = s; | |
186 | new_envstring->next = custom_environment; | |
187 | custom_environment = new_envstring; | |
188 | goto next_option; | |
189 | } | |
190 | cp = "from=\""; | |
191 | if (strncasecmp(opts, cp, strlen(cp)) == 0) { | |
192 | const char *remote_ip = get_remote_ipaddr(); | |
193 | const char *remote_host = get_canonical_hostname( | |
70791e56 | 194 | options.use_dns); |
3c0ef626 | 195 | char *patterns = xmalloc(strlen(opts) + 1); |
196 | ||
197 | opts += strlen(cp); | |
198 | i = 0; | |
199 | while (*opts) { | |
200 | if (*opts == '"') | |
201 | break; | |
202 | if (*opts == '\\' && opts[1] == '"') { | |
203 | opts += 2; | |
204 | patterns[i++] = '"'; | |
205 | continue; | |
206 | } | |
207 | patterns[i++] = *opts++; | |
208 | } | |
209 | if (!*opts) { | |
210 | debug("%.100s, line %lu: missing end quote", | |
211 | file, linenum); | |
2980ea68 | 212 | auth_debug_add("%.100s, line %lu: missing end quote", |
3c0ef626 | 213 | file, linenum); |
214 | xfree(patterns); | |
215 | goto bad_option; | |
216 | } | |
2e437378 | 217 | patterns[i] = '\0'; |
3c0ef626 | 218 | opts++; |
219 | if (match_host_and_ip(remote_host, remote_ip, | |
220 | patterns) != 1) { | |
221 | xfree(patterns); | |
70791e56 | 222 | logit("Authentication tried for %.100s with " |
3c0ef626 | 223 | "correct key but not from a permitted " |
224 | "host (host=%.200s, ip=%.200s).", | |
225 | pw->pw_name, remote_host, remote_ip); | |
2980ea68 | 226 | auth_debug_add("Your host '%.200s' is not " |
3c0ef626 | 227 | "permitted to use this key for login.", |
228 | remote_host); | |
229 | /* deny access */ | |
230 | return 0; | |
231 | } | |
232 | xfree(patterns); | |
233 | /* Host name matches. */ | |
234 | goto next_option; | |
235 | } | |
236 | cp = "permitopen=\""; | |
237 | if (strncasecmp(opts, cp, strlen(cp)) == 0) { | |
34fee935 | 238 | char *host, *p; |
3c0ef626 | 239 | u_short port; |
240 | char *patterns = xmalloc(strlen(opts) + 1); | |
241 | ||
242 | opts += strlen(cp); | |
243 | i = 0; | |
244 | while (*opts) { | |
245 | if (*opts == '"') | |
246 | break; | |
247 | if (*opts == '\\' && opts[1] == '"') { | |
248 | opts += 2; | |
249 | patterns[i++] = '"'; | |
250 | continue; | |
251 | } | |
252 | patterns[i++] = *opts++; | |
253 | } | |
254 | if (!*opts) { | |
255 | debug("%.100s, line %lu: missing end quote", | |
256 | file, linenum); | |
34fee935 | 257 | auth_debug_add("%.100s, line %lu: missing " |
258 | "end quote", file, linenum); | |
3c0ef626 | 259 | xfree(patterns); |
260 | goto bad_option; | |
261 | } | |
2e437378 | 262 | patterns[i] = '\0'; |
3c0ef626 | 263 | opts++; |
34fee935 | 264 | p = patterns; |
265 | host = hpdelim(&p); | |
266 | if (host == NULL || strlen(host) >= NI_MAXHOST) { | |
267 | debug("%.100s, line %lu: Bad permitopen " | |
268 | "specification <%.100s>", file, linenum, | |
269 | patterns); | |
2980ea68 | 270 | auth_debug_add("%.100s, line %lu: " |
34fee935 | 271 | "Bad permitopen specification", file, |
272 | linenum); | |
3c0ef626 | 273 | xfree(patterns); |
274 | goto bad_option; | |
275 | } | |
34fee935 | 276 | host = cleanhostname(host); |
277 | if (p == NULL || (port = a2port(p)) == 0) { | |
278 | debug("%.100s, line %lu: Bad permitopen port " | |
279 | "<%.100s>", file, linenum, p ? p : ""); | |
2980ea68 | 280 | auth_debug_add("%.100s, line %lu: " |
3c0ef626 | 281 | "Bad permitopen port", file, linenum); |
282 | xfree(patterns); | |
283 | goto bad_option; | |
284 | } | |
285 | if (options.allow_tcp_forwarding) | |
286 | channel_add_permitted_opens(host, port); | |
287 | xfree(patterns); | |
288 | goto next_option; | |
289 | } | |
e00da40d | 290 | cp = "tunnel=\""; |
291 | if (strncasecmp(opts, cp, strlen(cp)) == 0) { | |
292 | char *tun = NULL; | |
293 | opts += strlen(cp); | |
294 | tun = xmalloc(strlen(opts) + 1); | |
295 | i = 0; | |
296 | while (*opts) { | |
297 | if (*opts == '"') | |
298 | break; | |
299 | tun[i++] = *opts++; | |
300 | } | |
301 | if (!*opts) { | |
302 | debug("%.100s, line %lu: missing end quote", | |
303 | file, linenum); | |
304 | auth_debug_add("%.100s, line %lu: missing end quote", | |
305 | file, linenum); | |
306 | xfree(tun); | |
307 | forced_tun_device = -1; | |
308 | goto bad_option; | |
309 | } | |
2e437378 | 310 | tun[i] = '\0'; |
e00da40d | 311 | forced_tun_device = a2tun(tun, NULL); |
312 | xfree(tun); | |
313 | if (forced_tun_device == SSH_TUNID_ERR) { | |
314 | debug("%.100s, line %lu: invalid tun device", | |
315 | file, linenum); | |
316 | auth_debug_add("%.100s, line %lu: invalid tun device", | |
317 | file, linenum); | |
318 | forced_tun_device = -1; | |
319 | goto bad_option; | |
320 | } | |
321 | auth_debug_add("Forced tun device: %d", forced_tun_device); | |
322 | opts++; | |
323 | goto next_option; | |
324 | } | |
3c0ef626 | 325 | next_option: |
326 | /* | |
327 | * Skip the comma, and move to the next option | |
328 | * (or break out if there are no more). | |
329 | */ | |
330 | if (!*opts) | |
331 | fatal("Bugs in auth-options.c option processing."); | |
332 | if (*opts == ' ' || *opts == '\t') | |
333 | break; /* End of options. */ | |
334 | if (*opts != ',') | |
335 | goto bad_option; | |
336 | opts++; | |
337 | /* Process the next option. */ | |
338 | } | |
2980ea68 | 339 | |
340 | if (!use_privsep) | |
341 | auth_debug_send(); | |
342 | ||
3c0ef626 | 343 | /* grant access */ |
344 | return 1; | |
345 | ||
346 | bad_option: | |
70791e56 | 347 | logit("Bad options in %.100s file, line %lu: %.50s", |
3c0ef626 | 348 | file, linenum, opts); |
2980ea68 | 349 | auth_debug_add("Bad options in %.100s file, line %lu: %.50s", |
3c0ef626 | 350 | file, linenum, opts); |
2980ea68 | 351 | |
352 | if (!use_privsep) | |
353 | auth_debug_send(); | |
354 | ||
3c0ef626 | 355 | /* deny access */ |
356 | return 0; | |
357 | } |