blob: 443f5414ad1ed1ce76d7599dc21081eedfe8b173 [file] [log] [blame]
Damien Millere4340be2000-09-16 13:29:08 +11001/*
2 * Author: Tatu Ylonen <ylo@cs.hut.fi>
3 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4 * All rights reserved
Damien Millere4340be2000-09-16 13:29:08 +11005 * As far as I am concerned, the code I have written for this software
6 * can be used freely for any purpose. Any derived versions of this
7 * software must be clearly marked as such, and if the derived work is
8 * incompatible with the protocol description in the RFC file, it must be
9 * called by a name other than "ssh" or "Secure Shell".
10 */
11
Damien Millerf6d9e222000-06-18 14:50:44 +100012#include "includes.h"
Ben Lindstrom2d70f982001-03-19 00:13:46 +000013RCSID("$OpenBSD: auth-options.c,v 1.16 2001/03/18 12:07:52 markus Exp $");
Damien Millerf6d9e222000-06-18 14:50:44 +100014
Damien Millerf6d9e222000-06-18 14:50:44 +100015#include "packet.h"
16#include "xmalloc.h"
17#include "match.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000018#include "log.h"
19#include "canohost.h"
Ben Lindstrom7bb8b492001-03-17 00:47:54 +000020#include "channels.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000021#include "auth-options.h"
Damien Miller33804262001-02-04 23:20:18 +110022#include "servconf.h"
Damien Millerf6d9e222000-06-18 14:50:44 +100023
24/* Flags set authorized_keys flags */
25int no_port_forwarding_flag = 0;
26int no_agent_forwarding_flag = 0;
27int no_x11_forwarding_flag = 0;
28int no_pty_flag = 0;
29
30/* "command=" option. */
31char *forced_command = NULL;
32
33/* "environment=" options. */
34struct envstring *custom_environment = NULL;
35
Damien Miller33804262001-02-04 23:20:18 +110036extern ServerOptions options;
37
Damien Miller874d77b2000-10-14 16:23:11 +110038void
39auth_clear_options(void)
40{
41 no_agent_forwarding_flag = 0;
42 no_port_forwarding_flag = 0;
43 no_pty_flag = 0;
44 no_x11_forwarding_flag = 0;
45 while (custom_environment) {
46 struct envstring *ce = custom_environment;
47 custom_environment = ce->next;
48 xfree(ce->s);
49 xfree(ce);
50 }
51 if (forced_command) {
52 xfree(forced_command);
53 forced_command = NULL;
54 }
Ben Lindstrom7bb8b492001-03-17 00:47:54 +000055 channel_clear_permitted_opens();
Damien Miller874d77b2000-10-14 16:23:11 +110056}
57
Ben Lindstrom226cfa02001-01-22 05:34:40 +000058/*
59 * return 1 if access is granted, 0 if not.
60 * side effect: sets key option flags
61 */
Damien Millerf6d9e222000-06-18 14:50:44 +100062int
Damien Miller33804262001-02-04 23:20:18 +110063auth_parse_options(struct passwd *pw, char *opts, char *file, u_long linenum)
Damien Millerf6d9e222000-06-18 14:50:44 +100064{
65 const char *cp;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +000066 int i;
Damien Miller874d77b2000-10-14 16:23:11 +110067
68 /* reset options */
69 auth_clear_options();
70
Ben Lindstrom36d7bd02001-02-10 22:27:19 +000071 if (!opts)
72 return 1;
73
Damien Miller33804262001-02-04 23:20:18 +110074 while (*opts && *opts != ' ' && *opts != '\t') {
Damien Millerf6d9e222000-06-18 14:50:44 +100075 cp = "no-port-forwarding";
Damien Miller33804262001-02-04 23:20:18 +110076 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
Damien Millerf6d9e222000-06-18 14:50:44 +100077 packet_send_debug("Port forwarding disabled.");
78 no_port_forwarding_flag = 1;
Damien Miller33804262001-02-04 23:20:18 +110079 opts += strlen(cp);
Damien Millerf6d9e222000-06-18 14:50:44 +100080 goto next_option;
81 }
82 cp = "no-agent-forwarding";
Damien Miller33804262001-02-04 23:20:18 +110083 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
Damien Millerf6d9e222000-06-18 14:50:44 +100084 packet_send_debug("Agent forwarding disabled.");
85 no_agent_forwarding_flag = 1;
Damien Miller33804262001-02-04 23:20:18 +110086 opts += strlen(cp);
Damien Millerf6d9e222000-06-18 14:50:44 +100087 goto next_option;
88 }
89 cp = "no-X11-forwarding";
Damien Miller33804262001-02-04 23:20:18 +110090 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
Damien Millerf6d9e222000-06-18 14:50:44 +100091 packet_send_debug("X11 forwarding disabled.");
92 no_x11_forwarding_flag = 1;
Damien Miller33804262001-02-04 23:20:18 +110093 opts += strlen(cp);
Damien Millerf6d9e222000-06-18 14:50:44 +100094 goto next_option;
95 }
96 cp = "no-pty";
Damien Miller33804262001-02-04 23:20:18 +110097 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
Damien Millerf6d9e222000-06-18 14:50:44 +100098 packet_send_debug("Pty allocation disabled.");
99 no_pty_flag = 1;
Damien Miller33804262001-02-04 23:20:18 +1100100 opts += strlen(cp);
Damien Millerf6d9e222000-06-18 14:50:44 +1000101 goto next_option;
102 }
103 cp = "command=\"";
Damien Miller33804262001-02-04 23:20:18 +1100104 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
Damien Miller33804262001-02-04 23:20:18 +1100105 opts += strlen(cp);
106 forced_command = xmalloc(strlen(opts) + 1);
Damien Millerf6d9e222000-06-18 14:50:44 +1000107 i = 0;
Damien Miller33804262001-02-04 23:20:18 +1100108 while (*opts) {
109 if (*opts == '"')
Damien Millerf6d9e222000-06-18 14:50:44 +1000110 break;
Damien Miller33804262001-02-04 23:20:18 +1100111 if (*opts == '\\' && opts[1] == '"') {
112 opts += 2;
Damien Millerf6d9e222000-06-18 14:50:44 +1000113 forced_command[i++] = '"';
114 continue;
115 }
Damien Miller33804262001-02-04 23:20:18 +1100116 forced_command[i++] = *opts++;
Damien Millerf6d9e222000-06-18 14:50:44 +1000117 }
Damien Miller33804262001-02-04 23:20:18 +1100118 if (!*opts) {
Damien Millerf6d9e222000-06-18 14:50:44 +1000119 debug("%.100s, line %lu: missing end quote",
Ben Lindstrom226cfa02001-01-22 05:34:40 +0000120 file, linenum);
Damien Millerf6d9e222000-06-18 14:50:44 +1000121 packet_send_debug("%.100s, line %lu: missing end quote",
Ben Lindstrom226cfa02001-01-22 05:34:40 +0000122 file, linenum);
Damien Miller056ddf72001-03-14 10:15:20 +1100123 xfree(forced_command);
124 forced_command = NULL;
125 goto bad_option;
Damien Millerf6d9e222000-06-18 14:50:44 +1000126 }
127 forced_command[i] = 0;
128 packet_send_debug("Forced command: %.900s", forced_command);
Damien Miller33804262001-02-04 23:20:18 +1100129 opts++;
Damien Millerf6d9e222000-06-18 14:50:44 +1000130 goto next_option;
131 }
132 cp = "environment=\"";
Damien Miller33804262001-02-04 23:20:18 +1100133 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
Damien Millerf6d9e222000-06-18 14:50:44 +1000134 char *s;
135 struct envstring *new_envstring;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +0000136
Damien Miller33804262001-02-04 23:20:18 +1100137 opts += strlen(cp);
138 s = xmalloc(strlen(opts) + 1);
Damien Millerf6d9e222000-06-18 14:50:44 +1000139 i = 0;
Damien Miller33804262001-02-04 23:20:18 +1100140 while (*opts) {
141 if (*opts == '"')
Damien Millerf6d9e222000-06-18 14:50:44 +1000142 break;
Damien Miller33804262001-02-04 23:20:18 +1100143 if (*opts == '\\' && opts[1] == '"') {
144 opts += 2;
Damien Millerf6d9e222000-06-18 14:50:44 +1000145 s[i++] = '"';
146 continue;
147 }
Damien Miller33804262001-02-04 23:20:18 +1100148 s[i++] = *opts++;
Damien Millerf6d9e222000-06-18 14:50:44 +1000149 }
Damien Miller33804262001-02-04 23:20:18 +1100150 if (!*opts) {
Damien Millerf6d9e222000-06-18 14:50:44 +1000151 debug("%.100s, line %lu: missing end quote",
Ben Lindstrom226cfa02001-01-22 05:34:40 +0000152 file, linenum);
Damien Millerf6d9e222000-06-18 14:50:44 +1000153 packet_send_debug("%.100s, line %lu: missing end quote",
Ben Lindstrom226cfa02001-01-22 05:34:40 +0000154 file, linenum);
Damien Miller056ddf72001-03-14 10:15:20 +1100155 xfree(s);
156 goto bad_option;
Damien Millerf6d9e222000-06-18 14:50:44 +1000157 }
158 s[i] = 0;
159 packet_send_debug("Adding to environment: %.900s", s);
160 debug("Adding to environment: %.900s", s);
Damien Miller33804262001-02-04 23:20:18 +1100161 opts++;
Damien Millerf6d9e222000-06-18 14:50:44 +1000162 new_envstring = xmalloc(sizeof(struct envstring));
163 new_envstring->s = s;
164 new_envstring->next = custom_environment;
165 custom_environment = new_envstring;
166 goto next_option;
167 }
168 cp = "from=\"";
Damien Miller33804262001-02-04 23:20:18 +1100169 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
Damien Millerf6d9e222000-06-18 14:50:44 +1000170 int mname, mip;
Damien Miller33804262001-02-04 23:20:18 +1100171 const char *remote_ip = get_remote_ipaddr();
172 const char *remote_host = get_canonical_hostname(
173 options.reverse_mapping_check);
174 char *patterns = xmalloc(strlen(opts) + 1);
Ben Lindstrom7bb8b492001-03-17 00:47:54 +0000175
Damien Miller33804262001-02-04 23:20:18 +1100176 opts += strlen(cp);
Damien Millerf6d9e222000-06-18 14:50:44 +1000177 i = 0;
Damien Miller33804262001-02-04 23:20:18 +1100178 while (*opts) {
179 if (*opts == '"')
Damien Millerf6d9e222000-06-18 14:50:44 +1000180 break;
Damien Miller33804262001-02-04 23:20:18 +1100181 if (*opts == '\\' && opts[1] == '"') {
182 opts += 2;
Damien Millerf6d9e222000-06-18 14:50:44 +1000183 patterns[i++] = '"';
184 continue;
185 }
Damien Miller33804262001-02-04 23:20:18 +1100186 patterns[i++] = *opts++;
Damien Millerf6d9e222000-06-18 14:50:44 +1000187 }
Damien Miller33804262001-02-04 23:20:18 +1100188 if (!*opts) {
Damien Millerf6d9e222000-06-18 14:50:44 +1000189 debug("%.100s, line %lu: missing end quote",
Ben Lindstrom226cfa02001-01-22 05:34:40 +0000190 file, linenum);
Damien Millerf6d9e222000-06-18 14:50:44 +1000191 packet_send_debug("%.100s, line %lu: missing end quote",
Ben Lindstrom226cfa02001-01-22 05:34:40 +0000192 file, linenum);
Damien Miller056ddf72001-03-14 10:15:20 +1100193 xfree(patterns);
194 goto bad_option;
Damien Millerf6d9e222000-06-18 14:50:44 +1000195 }
196 patterns[i] = 0;
Damien Miller33804262001-02-04 23:20:18 +1100197 opts++;
Damien Millerf6d9e222000-06-18 14:50:44 +1000198 /*
199 * Deny access if we get a negative
200 * match for the hostname or the ip
201 * or if we get not match at all
202 */
Damien Miller33804262001-02-04 23:20:18 +1100203 mname = match_hostname(remote_host, patterns,
204 strlen(patterns));
205 mip = match_hostname(remote_ip, patterns,
206 strlen(patterns));
Damien Millerf6d9e222000-06-18 14:50:44 +1000207 xfree(patterns);
208 if (mname == -1 || mip == -1 ||
209 (mname != 1 && mip != 1)) {
Damien Miller33804262001-02-04 23:20:18 +1100210 log("Authentication tried for %.100s with "
211 "correct key but not from a permitted "
212 "host (host=%.200s, ip=%.200s).",
213 pw->pw_name, remote_host, remote_ip);
214 packet_send_debug("Your host '%.200s' is not "
215 "permitted to use this key for login.",
216 remote_host);
Damien Millerf6d9e222000-06-18 14:50:44 +1000217 /* deny access */
218 return 0;
219 }
220 /* Host name matches. */
221 goto next_option;
222 }
Ben Lindstrom7bb8b492001-03-17 00:47:54 +0000223 cp = "permitopen=\"";
224 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
225 u_short port;
226 char *c, *ep;
227 char *patterns = xmalloc(strlen(opts) + 1);
228
229 opts += strlen(cp);
230 i = 0;
231 while (*opts) {
232 if (*opts == '"')
233 break;
234 if (*opts == '\\' && opts[1] == '"') {
235 opts += 2;
236 patterns[i++] = '"';
237 continue;
238 }
239 patterns[i++] = *opts++;
240 }
241 if (!*opts) {
242 debug("%.100s, line %lu: missing end quote",
243 file, linenum);
244 packet_send_debug("%.100s, line %lu: missing end quote",
245 file, linenum);
246 xfree(patterns);
247 goto bad_option;
248 }
249 patterns[i] = 0;
250 opts++;
251 c = strchr(patterns, ':');
252 if (c == NULL) {
253 debug("%.100s, line %lu: permitopen: missing colon <%.100s>",
254 file, linenum, patterns);
255 packet_send_debug("%.100s, line %lu: missing colon",
256 file, linenum);
257 xfree(patterns);
258 goto bad_option;
259 }
260 *c = 0;
261 c++;
262 port = strtol(c, &ep, 0);
263 if (c == ep) {
264 debug("%.100s, line %lu: permitopen: missing port <%.100s>",
265 file, linenum, patterns);
266 packet_send_debug("%.100s, line %lu: missing port",
267 file, linenum);
268 xfree(patterns);
269 goto bad_option;
270 }
Ben Lindstrom2d70f982001-03-19 00:13:46 +0000271 if (options.allow_tcp_forwarding)
272 channel_add_permitted_opens(patterns, port);
Ben Lindstrom7bb8b492001-03-17 00:47:54 +0000273 xfree(patterns);
274 goto next_option;
275 }
Damien Millerf6d9e222000-06-18 14:50:44 +1000276next_option:
277 /*
278 * Skip the comma, and move to the next option
279 * (or break out if there are no more).
280 */
Damien Miller33804262001-02-04 23:20:18 +1100281 if (!*opts)
Damien Millerf6d9e222000-06-18 14:50:44 +1000282 fatal("Bugs in auth-options.c option processing.");
Damien Miller33804262001-02-04 23:20:18 +1100283 if (*opts == ' ' || *opts == '\t')
Damien Millerf6d9e222000-06-18 14:50:44 +1000284 break; /* End of options. */
Damien Miller33804262001-02-04 23:20:18 +1100285 if (*opts != ',')
Damien Millerf6d9e222000-06-18 14:50:44 +1000286 goto bad_option;
Damien Miller33804262001-02-04 23:20:18 +1100287 opts++;
Damien Millerf6d9e222000-06-18 14:50:44 +1000288 /* Process the next option. */
289 }
290 /* grant access */
291 return 1;
292
293bad_option:
294 log("Bad options in %.100s file, line %lu: %.50s",
Damien Miller33804262001-02-04 23:20:18 +1100295 file, linenum, opts);
Damien Millerf6d9e222000-06-18 14:50:44 +1000296 packet_send_debug("Bad options in %.100s file, line %lu: %.50s",
Damien Miller33804262001-02-04 23:20:18 +1100297 file, linenum, opts);
Damien Millerf6d9e222000-06-18 14:50:44 +1000298 /* deny access */
299 return 0;
300}