blob: 0595537beee96331fe10bfa5a1d859b718631646 [file] [log] [blame]
djm@openbsd.orgca42c172015-04-22 01:24:01 +00001/* $OpenBSD: auth-options.c,v 1.66 2015/04/22 01:24:01 djm Exp $ */
Damien Millere4340be2000-09-16 13:29:08 +11002/*
3 * Author: Tatu Ylonen <ylo@cs.hut.fi>
4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5 * All rights reserved
Damien Millere4340be2000-09-16 13:29:08 +11006 * 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
Damien Millerf6d9e222000-06-18 14:50:44 +100013#include "includes.h"
Damien Millerf6d9e222000-06-18 14:50:44 +100014
Damien Miller9f2abc42006-07-10 20:53:08 +100015#include <sys/types.h>
16
Damien Millerb8fe89c2006-07-24 14:51:00 +100017#include <netdb.h>
Damien Miller9f2abc42006-07-10 20:53:08 +100018#include <pwd.h>
Damien Millere3476ed2006-07-24 14:13:33 +100019#include <string.h>
Damien Millerd7834352006-08-05 12:39:39 +100020#include <stdio.h>
21#include <stdarg.h>
Damien Miller9f2abc42006-07-10 20:53:08 +100022
Damien Millerb84886b2008-05-19 15:05:07 +100023#include "openbsd-compat/sys-queue.h"
markus@openbsd.orgae8b4632015-01-14 10:30:34 +000024
25#include "key.h" /* XXX for typedef */
26#include "buffer.h" /* XXX for typedef */
Damien Millerf6d9e222000-06-18 14:50:44 +100027#include "xmalloc.h"
28#include "match.h"
markus@openbsd.orgae8b4632015-01-14 10:30:34 +000029#include "ssherr.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000030#include "log.h"
31#include "canohost.h"
markus@openbsd.orgae8b4632015-01-14 10:30:34 +000032#include "sshbuf.h"
Damien Miller7acefbb2014-07-18 14:11:24 +100033#include "misc.h"
Ben Lindstromc7637672001-06-09 00:36:26 +000034#include "channels.h"
Damien Miller33804262001-02-04 23:20:18 +110035#include "servconf.h"
markus@openbsd.orgae8b4632015-01-14 10:30:34 +000036#include "sshkey.h"
Damien Miller4e270b02010-04-16 15:56:21 +100037#include "auth-options.h"
Damien Millerd7834352006-08-05 12:39:39 +100038#include "hostfile.h"
Ben Lindstroma574cda2002-05-15 16:16:14 +000039#include "auth.h"
Damien Millerf6d9e222000-06-18 14:50:44 +100040
41/* Flags set authorized_keys flags */
42int no_port_forwarding_flag = 0;
43int no_agent_forwarding_flag = 0;
44int no_x11_forwarding_flag = 0;
45int no_pty_flag = 0;
Damien Miller95e80952008-03-27 11:03:05 +110046int no_user_rc = 0;
Damien Miller0a80ca12010-02-27 07:55:05 +110047int key_is_cert_authority = 0;
Damien Millerf6d9e222000-06-18 14:50:44 +100048
49/* "command=" option. */
50char *forced_command = NULL;
51
52/* "environment=" options. */
53struct envstring *custom_environment = NULL;
54
Damien Millerd27b9472005-12-13 19:29:02 +110055/* "tunnel=" option. */
56int forced_tun_device = -1;
57
Damien Miller30da3442010-05-10 11:58:03 +100058/* "principals=" option. */
59char *authorized_principals = NULL;
60
Damien Miller33804262001-02-04 23:20:18 +110061extern ServerOptions options;
62
Ben Lindstrom7a2073c2002-03-22 02:30:41 +000063void
Damien Miller874d77b2000-10-14 16:23:11 +110064auth_clear_options(void)
65{
66 no_agent_forwarding_flag = 0;
67 no_port_forwarding_flag = 0;
68 no_pty_flag = 0;
69 no_x11_forwarding_flag = 0;
Damien Miller95e80952008-03-27 11:03:05 +110070 no_user_rc = 0;
Damien Miller0a80ca12010-02-27 07:55:05 +110071 key_is_cert_authority = 0;
Damien Miller874d77b2000-10-14 16:23:11 +110072 while (custom_environment) {
73 struct envstring *ce = custom_environment;
74 custom_environment = ce->next;
Darren Tuckera627d422013-06-02 07:31:17 +100075 free(ce->s);
76 free(ce);
Damien Miller874d77b2000-10-14 16:23:11 +110077 }
78 if (forced_command) {
Darren Tuckera627d422013-06-02 07:31:17 +100079 free(forced_command);
Damien Miller874d77b2000-10-14 16:23:11 +110080 forced_command = NULL;
81 }
Damien Miller30da3442010-05-10 11:58:03 +100082 if (authorized_principals) {
Darren Tuckera627d422013-06-02 07:31:17 +100083 free(authorized_principals);
Damien Miller30da3442010-05-10 11:58:03 +100084 authorized_principals = NULL;
85 }
Damien Millerd27b9472005-12-13 19:29:02 +110086 forced_tun_device = -1;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +000087 channel_clear_permitted_opens();
Damien Miller874d77b2000-10-14 16:23:11 +110088}
89
Ben Lindstrom226cfa02001-01-22 05:34:40 +000090/*
91 * return 1 if access is granted, 0 if not.
92 * side effect: sets key option flags
93 */
Damien Millerf6d9e222000-06-18 14:50:44 +100094int
Damien Miller33804262001-02-04 23:20:18 +110095auth_parse_options(struct passwd *pw, char *opts, char *file, u_long linenum)
Damien Millerf6d9e222000-06-18 14:50:44 +100096{
97 const char *cp;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +000098 int i;
Damien Miller874d77b2000-10-14 16:23:11 +110099
100 /* reset options */
101 auth_clear_options();
102
Ben Lindstrom36d7bd02001-02-10 22:27:19 +0000103 if (!opts)
104 return 1;
105
Damien Miller33804262001-02-04 23:20:18 +1100106 while (*opts && *opts != ' ' && *opts != '\t') {
Damien Miller0a80ca12010-02-27 07:55:05 +1100107 cp = "cert-authority";
108 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
109 key_is_cert_authority = 1;
110 opts += strlen(cp);
111 goto next_option;
112 }
Damien Millerf6d9e222000-06-18 14:50:44 +1000113 cp = "no-port-forwarding";
Damien Miller33804262001-02-04 23:20:18 +1100114 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
Ben Lindstroma574cda2002-05-15 16:16:14 +0000115 auth_debug_add("Port forwarding disabled.");
Damien Millerf6d9e222000-06-18 14:50:44 +1000116 no_port_forwarding_flag = 1;
Damien Miller33804262001-02-04 23:20:18 +1100117 opts += strlen(cp);
Damien Millerf6d9e222000-06-18 14:50:44 +1000118 goto next_option;
119 }
120 cp = "no-agent-forwarding";
Damien Miller33804262001-02-04 23:20:18 +1100121 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
Ben Lindstroma574cda2002-05-15 16:16:14 +0000122 auth_debug_add("Agent forwarding disabled.");
Damien Millerf6d9e222000-06-18 14:50:44 +1000123 no_agent_forwarding_flag = 1;
Damien Miller33804262001-02-04 23:20:18 +1100124 opts += strlen(cp);
Damien Millerf6d9e222000-06-18 14:50:44 +1000125 goto next_option;
126 }
127 cp = "no-X11-forwarding";
Damien Miller33804262001-02-04 23:20:18 +1100128 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
Ben Lindstroma574cda2002-05-15 16:16:14 +0000129 auth_debug_add("X11 forwarding disabled.");
Damien Millerf6d9e222000-06-18 14:50:44 +1000130 no_x11_forwarding_flag = 1;
Damien Miller33804262001-02-04 23:20:18 +1100131 opts += strlen(cp);
Damien Millerf6d9e222000-06-18 14:50:44 +1000132 goto next_option;
133 }
134 cp = "no-pty";
Damien Miller33804262001-02-04 23:20:18 +1100135 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
Ben Lindstroma574cda2002-05-15 16:16:14 +0000136 auth_debug_add("Pty allocation disabled.");
Damien Millerf6d9e222000-06-18 14:50:44 +1000137 no_pty_flag = 1;
Damien Miller33804262001-02-04 23:20:18 +1100138 opts += strlen(cp);
Damien Millerf6d9e222000-06-18 14:50:44 +1000139 goto next_option;
140 }
Damien Miller95e80952008-03-27 11:03:05 +1100141 cp = "no-user-rc";
142 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
143 auth_debug_add("User rc file execution disabled.");
144 no_user_rc = 1;
145 opts += strlen(cp);
146 goto next_option;
147 }
Damien Millerf6d9e222000-06-18 14:50:44 +1000148 cp = "command=\"";
Damien Miller33804262001-02-04 23:20:18 +1100149 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
Damien Miller33804262001-02-04 23:20:18 +1100150 opts += strlen(cp);
Damien Miller30da3442010-05-10 11:58:03 +1000151 if (forced_command != NULL)
Darren Tuckera627d422013-06-02 07:31:17 +1000152 free(forced_command);
Damien Miller33804262001-02-04 23:20:18 +1100153 forced_command = xmalloc(strlen(opts) + 1);
Damien Millerf6d9e222000-06-18 14:50:44 +1000154 i = 0;
Damien Miller33804262001-02-04 23:20:18 +1100155 while (*opts) {
156 if (*opts == '"')
Damien Millerf6d9e222000-06-18 14:50:44 +1000157 break;
Damien Miller33804262001-02-04 23:20:18 +1100158 if (*opts == '\\' && opts[1] == '"') {
159 opts += 2;
Damien Millerf6d9e222000-06-18 14:50:44 +1000160 forced_command[i++] = '"';
161 continue;
162 }
Damien Miller33804262001-02-04 23:20:18 +1100163 forced_command[i++] = *opts++;
Damien Millerf6d9e222000-06-18 14:50:44 +1000164 }
Damien Miller33804262001-02-04 23:20:18 +1100165 if (!*opts) {
Damien Millerf6d9e222000-06-18 14:50:44 +1000166 debug("%.100s, line %lu: missing end quote",
Ben Lindstrom226cfa02001-01-22 05:34:40 +0000167 file, linenum);
Ben Lindstroma574cda2002-05-15 16:16:14 +0000168 auth_debug_add("%.100s, line %lu: missing end quote",
Ben Lindstrom226cfa02001-01-22 05:34:40 +0000169 file, linenum);
Darren Tuckera627d422013-06-02 07:31:17 +1000170 free(forced_command);
Damien Miller056ddf72001-03-14 10:15:20 +1100171 forced_command = NULL;
172 goto bad_option;
Damien Millerf6d9e222000-06-18 14:50:44 +1000173 }
Damien Miller98299262006-07-24 14:01:43 +1000174 forced_command[i] = '\0';
Damien Millerde53fd02011-01-06 22:44:18 +1100175 auth_debug_add("Forced command.");
Damien Miller33804262001-02-04 23:20:18 +1100176 opts++;
Damien Millerf6d9e222000-06-18 14:50:44 +1000177 goto next_option;
178 }
Damien Miller30da3442010-05-10 11:58:03 +1000179 cp = "principals=\"";
180 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
181 opts += strlen(cp);
182 if (authorized_principals != NULL)
Darren Tuckera627d422013-06-02 07:31:17 +1000183 free(authorized_principals);
Damien Miller30da3442010-05-10 11:58:03 +1000184 authorized_principals = xmalloc(strlen(opts) + 1);
185 i = 0;
186 while (*opts) {
187 if (*opts == '"')
188 break;
189 if (*opts == '\\' && opts[1] == '"') {
190 opts += 2;
191 authorized_principals[i++] = '"';
192 continue;
193 }
194 authorized_principals[i++] = *opts++;
195 }
196 if (!*opts) {
197 debug("%.100s, line %lu: missing end quote",
198 file, linenum);
199 auth_debug_add("%.100s, line %lu: missing end quote",
200 file, linenum);
Darren Tuckera627d422013-06-02 07:31:17 +1000201 free(authorized_principals);
Damien Miller30da3442010-05-10 11:58:03 +1000202 authorized_principals = NULL;
203 goto bad_option;
204 }
205 authorized_principals[i] = '\0';
206 auth_debug_add("principals: %.900s",
207 authorized_principals);
208 opts++;
209 goto next_option;
210 }
Damien Millerf6d9e222000-06-18 14:50:44 +1000211 cp = "environment=\"";
Ben Lindstrom5d860f02002-08-01 01:28:38 +0000212 if (options.permit_user_env &&
213 strncasecmp(opts, cp, strlen(cp)) == 0) {
Damien Millerf6d9e222000-06-18 14:50:44 +1000214 char *s;
215 struct envstring *new_envstring;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +0000216
Damien Miller33804262001-02-04 23:20:18 +1100217 opts += strlen(cp);
218 s = xmalloc(strlen(opts) + 1);
Damien Millerf6d9e222000-06-18 14:50:44 +1000219 i = 0;
Damien Miller33804262001-02-04 23:20:18 +1100220 while (*opts) {
221 if (*opts == '"')
Damien Millerf6d9e222000-06-18 14:50:44 +1000222 break;
Damien Miller33804262001-02-04 23:20:18 +1100223 if (*opts == '\\' && opts[1] == '"') {
224 opts += 2;
Damien Millerf6d9e222000-06-18 14:50:44 +1000225 s[i++] = '"';
226 continue;
227 }
Damien Miller33804262001-02-04 23:20:18 +1100228 s[i++] = *opts++;
Damien Millerf6d9e222000-06-18 14:50:44 +1000229 }
Damien Miller33804262001-02-04 23:20:18 +1100230 if (!*opts) {
Damien Millerf6d9e222000-06-18 14:50:44 +1000231 debug("%.100s, line %lu: missing end quote",
Ben Lindstrom226cfa02001-01-22 05:34:40 +0000232 file, linenum);
Ben Lindstroma574cda2002-05-15 16:16:14 +0000233 auth_debug_add("%.100s, line %lu: missing end quote",
Ben Lindstrom226cfa02001-01-22 05:34:40 +0000234 file, linenum);
Darren Tuckera627d422013-06-02 07:31:17 +1000235 free(s);
Damien Miller056ddf72001-03-14 10:15:20 +1100236 goto bad_option;
Damien Millerf6d9e222000-06-18 14:50:44 +1000237 }
Damien Miller98299262006-07-24 14:01:43 +1000238 s[i] = '\0';
Ben Lindstroma574cda2002-05-15 16:16:14 +0000239 auth_debug_add("Adding to environment: %.900s", s);
Damien Millerf6d9e222000-06-18 14:50:44 +1000240 debug("Adding to environment: %.900s", s);
Damien Miller33804262001-02-04 23:20:18 +1100241 opts++;
Damien Miller6c81fee2013-11-08 12:19:55 +1100242 new_envstring = xcalloc(1, sizeof(struct envstring));
Damien Millerf6d9e222000-06-18 14:50:44 +1000243 new_envstring->s = s;
244 new_envstring->next = custom_environment;
245 custom_environment = new_envstring;
246 goto next_option;
247 }
248 cp = "from=\"";
Damien Miller33804262001-02-04 23:20:18 +1100249 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
Damien Miller33804262001-02-04 23:20:18 +1100250 const char *remote_ip = get_remote_ipaddr();
251 const char *remote_host = get_canonical_hostname(
Damien Miller3a961dc2003-06-03 10:25:48 +1000252 options.use_dns);
Damien Miller33804262001-02-04 23:20:18 +1100253 char *patterns = xmalloc(strlen(opts) + 1);
Ben Lindstrom7bb8b492001-03-17 00:47:54 +0000254
Damien Miller33804262001-02-04 23:20:18 +1100255 opts += strlen(cp);
Damien Millerf6d9e222000-06-18 14:50:44 +1000256 i = 0;
Damien Miller33804262001-02-04 23:20:18 +1100257 while (*opts) {
258 if (*opts == '"')
Damien Millerf6d9e222000-06-18 14:50:44 +1000259 break;
Damien Miller33804262001-02-04 23:20:18 +1100260 if (*opts == '\\' && opts[1] == '"') {
261 opts += 2;
Damien Millerf6d9e222000-06-18 14:50:44 +1000262 patterns[i++] = '"';
263 continue;
264 }
Damien Miller33804262001-02-04 23:20:18 +1100265 patterns[i++] = *opts++;
Damien Millerf6d9e222000-06-18 14:50:44 +1000266 }
Damien Miller33804262001-02-04 23:20:18 +1100267 if (!*opts) {
Damien Millerf6d9e222000-06-18 14:50:44 +1000268 debug("%.100s, line %lu: missing end quote",
Ben Lindstrom226cfa02001-01-22 05:34:40 +0000269 file, linenum);
Ben Lindstroma574cda2002-05-15 16:16:14 +0000270 auth_debug_add("%.100s, line %lu: missing end quote",
Ben Lindstrom226cfa02001-01-22 05:34:40 +0000271 file, linenum);
Darren Tuckera627d422013-06-02 07:31:17 +1000272 free(patterns);
Damien Miller056ddf72001-03-14 10:15:20 +1100273 goto bad_option;
Damien Millerf6d9e222000-06-18 14:50:44 +1000274 }
Damien Miller98299262006-07-24 14:01:43 +1000275 patterns[i] = '\0';
Damien Miller33804262001-02-04 23:20:18 +1100276 opts++;
Darren Tucker896ad5a2008-06-11 09:34:46 +1000277 switch (match_host_and_ip(remote_host, remote_ip,
278 patterns)) {
279 case 1:
Darren Tuckera627d422013-06-02 07:31:17 +1000280 free(patterns);
Darren Tucker896ad5a2008-06-11 09:34:46 +1000281 /* Host name matches. */
282 goto next_option;
283 case -1:
284 debug("%.100s, line %lu: invalid criteria",
285 file, linenum);
286 auth_debug_add("%.100s, line %lu: "
287 "invalid criteria", file, linenum);
288 /* FALLTHROUGH */
289 case 0:
Darren Tuckera627d422013-06-02 07:31:17 +1000290 free(patterns);
Damien Miller996acd22003-04-09 20:59:48 +1000291 logit("Authentication tried for %.100s with "
Damien Miller33804262001-02-04 23:20:18 +1100292 "correct key but not from a permitted "
293 "host (host=%.200s, ip=%.200s).",
294 pw->pw_name, remote_host, remote_ip);
Ben Lindstroma574cda2002-05-15 16:16:14 +0000295 auth_debug_add("Your host '%.200s' is not "
Damien Miller33804262001-02-04 23:20:18 +1100296 "permitted to use this key for login.",
297 remote_host);
Darren Tucker896ad5a2008-06-11 09:34:46 +1000298 break;
Damien Millerf6d9e222000-06-18 14:50:44 +1000299 }
Darren Tucker896ad5a2008-06-11 09:34:46 +1000300 /* deny access */
301 return 0;
Damien Millerf6d9e222000-06-18 14:50:44 +1000302 }
Ben Lindstrom7bb8b492001-03-17 00:47:54 +0000303 cp = "permitopen=\"";
304 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
Damien Millerf91ee4c2005-03-01 21:24:33 +1100305 char *host, *p;
Damien Millere37dde02009-01-28 16:33:01 +1100306 int port;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +0000307 char *patterns = xmalloc(strlen(opts) + 1);
308
309 opts += strlen(cp);
310 i = 0;
311 while (*opts) {
312 if (*opts == '"')
313 break;
314 if (*opts == '\\' && opts[1] == '"') {
315 opts += 2;
316 patterns[i++] = '"';
317 continue;
318 }
319 patterns[i++] = *opts++;
320 }
321 if (!*opts) {
322 debug("%.100s, line %lu: missing end quote",
323 file, linenum);
Damien Millerf91ee4c2005-03-01 21:24:33 +1100324 auth_debug_add("%.100s, line %lu: missing "
325 "end quote", file, linenum);
Darren Tuckera627d422013-06-02 07:31:17 +1000326 free(patterns);
Ben Lindstrom7bb8b492001-03-17 00:47:54 +0000327 goto bad_option;
328 }
Damien Miller98299262006-07-24 14:01:43 +1000329 patterns[i] = '\0';
Ben Lindstrom7bb8b492001-03-17 00:47:54 +0000330 opts++;
Damien Millerf91ee4c2005-03-01 21:24:33 +1100331 p = patterns;
Damien Miller7acefbb2014-07-18 14:11:24 +1000332 /* XXX - add streamlocal support */
Damien Millerf91ee4c2005-03-01 21:24:33 +1100333 host = hpdelim(&p);
334 if (host == NULL || strlen(host) >= NI_MAXHOST) {
335 debug("%.100s, line %lu: Bad permitopen "
Darren Tucker90b9e022005-03-14 23:08:50 +1100336 "specification <%.100s>", file, linenum,
Damien Millerf91ee4c2005-03-01 21:24:33 +1100337 patterns);
Ben Lindstroma574cda2002-05-15 16:16:14 +0000338 auth_debug_add("%.100s, line %lu: "
Damien Millerf91ee4c2005-03-01 21:24:33 +1100339 "Bad permitopen specification", file,
340 linenum);
Darren Tuckera627d422013-06-02 07:31:17 +1000341 free(patterns);
Ben Lindstrom7bb8b492001-03-17 00:47:54 +0000342 goto bad_option;
343 }
Darren Tucker47eede72005-03-14 23:08:12 +1100344 host = cleanhostname(host);
Darren Tucker1338b9e2011-10-02 18:57:35 +1100345 if (p == NULL || (port = permitopen_port(p)) < 0) {
Damien Millerf91ee4c2005-03-01 21:24:33 +1100346 debug("%.100s, line %lu: Bad permitopen port "
347 "<%.100s>", file, linenum, p ? p : "");
Ben Lindstroma574cda2002-05-15 16:16:14 +0000348 auth_debug_add("%.100s, line %lu: "
Ben Lindstromd71ba572001-09-12 18:03:31 +0000349 "Bad permitopen port", file, linenum);
Darren Tuckera627d422013-06-02 07:31:17 +1000350 free(patterns);
Ben Lindstrom7bb8b492001-03-17 00:47:54 +0000351 goto bad_option;
352 }
Damien Milleraa5b3f82012-12-03 09:50:54 +1100353 if ((options.allow_tcp_forwarding & FORWARD_LOCAL) != 0)
Ben Lindstromd71ba572001-09-12 18:03:31 +0000354 channel_add_permitted_opens(host, port);
Darren Tuckera627d422013-06-02 07:31:17 +1000355 free(patterns);
Ben Lindstrom7bb8b492001-03-17 00:47:54 +0000356 goto next_option;
357 }
Damien Millerd27b9472005-12-13 19:29:02 +1100358 cp = "tunnel=\"";
359 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
360 char *tun = NULL;
361 opts += strlen(cp);
362 tun = xmalloc(strlen(opts) + 1);
363 i = 0;
364 while (*opts) {
365 if (*opts == '"')
366 break;
367 tun[i++] = *opts++;
368 }
369 if (!*opts) {
370 debug("%.100s, line %lu: missing end quote",
371 file, linenum);
372 auth_debug_add("%.100s, line %lu: missing end quote",
373 file, linenum);
Darren Tuckera627d422013-06-02 07:31:17 +1000374 free(tun);
Damien Millerd27b9472005-12-13 19:29:02 +1100375 forced_tun_device = -1;
376 goto bad_option;
377 }
Damien Miller98299262006-07-24 14:01:43 +1000378 tun[i] = '\0';
Damien Millerd27b9472005-12-13 19:29:02 +1100379 forced_tun_device = a2tun(tun, NULL);
Darren Tuckera627d422013-06-02 07:31:17 +1000380 free(tun);
Damien Miller7b58e802005-12-13 19:33:19 +1100381 if (forced_tun_device == SSH_TUNID_ERR) {
Damien Millerd27b9472005-12-13 19:29:02 +1100382 debug("%.100s, line %lu: invalid tun device",
383 file, linenum);
384 auth_debug_add("%.100s, line %lu: invalid tun device",
385 file, linenum);
386 forced_tun_device = -1;
387 goto bad_option;
388 }
389 auth_debug_add("Forced tun device: %d", forced_tun_device);
390 opts++;
391 goto next_option;
392 }
Damien Millerf6d9e222000-06-18 14:50:44 +1000393next_option:
394 /*
395 * Skip the comma, and move to the next option
396 * (or break out if there are no more).
397 */
Damien Miller33804262001-02-04 23:20:18 +1100398 if (!*opts)
Damien Millerf6d9e222000-06-18 14:50:44 +1000399 fatal("Bugs in auth-options.c option processing.");
Damien Miller33804262001-02-04 23:20:18 +1100400 if (*opts == ' ' || *opts == '\t')
Damien Millerf6d9e222000-06-18 14:50:44 +1000401 break; /* End of options. */
Damien Miller33804262001-02-04 23:20:18 +1100402 if (*opts != ',')
Damien Millerf6d9e222000-06-18 14:50:44 +1000403 goto bad_option;
Damien Miller33804262001-02-04 23:20:18 +1100404 opts++;
Damien Millerf6d9e222000-06-18 14:50:44 +1000405 /* Process the next option. */
406 }
Ben Lindstrom7a2073c2002-03-22 02:30:41 +0000407
Damien Millerf6d9e222000-06-18 14:50:44 +1000408 /* grant access */
409 return 1;
410
411bad_option:
Damien Miller996acd22003-04-09 20:59:48 +1000412 logit("Bad options in %.100s file, line %lu: %.50s",
Damien Miller33804262001-02-04 23:20:18 +1100413 file, linenum, opts);
Ben Lindstroma574cda2002-05-15 16:16:14 +0000414 auth_debug_add("Bad options in %.100s file, line %lu: %.50s",
Damien Miller33804262001-02-04 23:20:18 +1100415 file, linenum, opts);
Ben Lindstrom7a2073c2002-03-22 02:30:41 +0000416
Damien Millerf6d9e222000-06-18 14:50:44 +1000417 /* deny access */
418 return 0;
419}
Damien Miller0a80ca12010-02-27 07:55:05 +1100420
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000421#define OPTIONS_CRITICAL 1
422#define OPTIONS_EXTENSIONS 2
423static int
markus@openbsd.orgae8b4632015-01-14 10:30:34 +0000424parse_option_list(struct sshbuf *oblob, struct passwd *pw,
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000425 u_int which, int crit,
426 int *cert_no_port_forwarding_flag,
427 int *cert_no_agent_forwarding_flag,
428 int *cert_no_x11_forwarding_flag,
429 int *cert_no_pty_flag,
430 int *cert_no_user_rc,
431 char **cert_forced_command,
432 int *cert_source_address_done)
Damien Miller0a80ca12010-02-27 07:55:05 +1100433{
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000434 char *command, *allowed;
435 const char *remote_ip;
Damien Millerce986542013-07-18 16:12:44 +1000436 char *name = NULL;
markus@openbsd.orgae8b4632015-01-14 10:30:34 +0000437 struct sshbuf *c = NULL, *data = NULL;
438 int r, ret = -1, result, found;
Damien Miller0a80ca12010-02-27 07:55:05 +1100439
markus@openbsd.orgae8b4632015-01-14 10:30:34 +0000440 if ((c = sshbuf_fromb(oblob)) == NULL) {
441 error("%s: sshbuf_fromb failed", __func__);
442 goto out;
443 }
Damien Miller0a80ca12010-02-27 07:55:05 +1100444
markus@openbsd.orgae8b4632015-01-14 10:30:34 +0000445 while (sshbuf_len(c) > 0) {
446 sshbuf_free(data);
447 data = NULL;
448 if ((r = sshbuf_get_cstring(c, &name, NULL)) != 0 ||
449 (r = sshbuf_froms(c, &data)) != 0) {
450 error("Unable to parse certificate options: %s",
451 ssh_err(r));
Damien Miller0a80ca12010-02-27 07:55:05 +1100452 goto out;
453 }
markus@openbsd.orgae8b4632015-01-14 10:30:34 +0000454 debug3("found certificate option \"%.100s\" len %zu",
455 name, sshbuf_len(data));
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000456 found = 0;
457 if ((which & OPTIONS_EXTENSIONS) != 0) {
458 if (strcmp(name, "permit-X11-forwarding") == 0) {
459 *cert_no_x11_forwarding_flag = 0;
460 found = 1;
461 } else if (strcmp(name,
462 "permit-agent-forwarding") == 0) {
463 *cert_no_agent_forwarding_flag = 0;
464 found = 1;
465 } else if (strcmp(name,
466 "permit-port-forwarding") == 0) {
467 *cert_no_port_forwarding_flag = 0;
468 found = 1;
469 } else if (strcmp(name, "permit-pty") == 0) {
470 *cert_no_pty_flag = 0;
471 found = 1;
472 } else if (strcmp(name, "permit-user-rc") == 0) {
473 *cert_no_user_rc = 0;
474 found = 1;
Damien Miller0a80ca12010-02-27 07:55:05 +1100475 }
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000476 }
477 if (!found && (which & OPTIONS_CRITICAL) != 0) {
478 if (strcmp(name, "force-command") == 0) {
markus@openbsd.orgae8b4632015-01-14 10:30:34 +0000479 if ((r = sshbuf_get_cstring(data, &command,
480 NULL)) != 0) {
481 error("Unable to parse \"%s\" "
482 "section: %s", name, ssh_err(r));
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000483 goto out;
484 }
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000485 if (*cert_forced_command != NULL) {
486 error("Certificate has multiple "
487 "force-command options");
Darren Tuckera627d422013-06-02 07:31:17 +1000488 free(command);
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000489 goto out;
490 }
491 *cert_forced_command = command;
492 found = 1;
Damien Miller41396572010-03-04 21:51:11 +1100493 }
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000494 if (strcmp(name, "source-address") == 0) {
markus@openbsd.orgae8b4632015-01-14 10:30:34 +0000495 if ((r = sshbuf_get_cstring(data, &allowed,
496 NULL)) != 0) {
497 error("Unable to parse \"%s\" "
498 "section: %s", name, ssh_err(r));
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000499 goto out;
500 }
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000501 if ((*cert_source_address_done)++) {
502 error("Certificate has multiple "
503 "source-address options");
Darren Tuckera627d422013-06-02 07:31:17 +1000504 free(allowed);
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000505 goto out;
506 }
507 remote_ip = get_remote_ipaddr();
Damien Millerbf25d112013-12-29 17:44:56 +1100508 result = addr_match_cidr_list(remote_ip,
509 allowed);
510 free(allowed);
511 switch (result) {
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000512 case 1:
513 /* accepted */
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000514 break;
515 case 0:
516 /* no match */
517 logit("Authentication tried for %.100s "
518 "with valid certificate but not "
519 "from a permitted host "
520 "(ip=%.200s).", pw->pw_name,
521 remote_ip);
522 auth_debug_add("Your address '%.200s' "
523 "is not permitted to use this "
524 "certificate for login.",
525 remote_ip);
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000526 goto out;
527 case -1:
Damien Millerbf25d112013-12-29 17:44:56 +1100528 default:
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000529 error("Certificate source-address "
530 "contents invalid");
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000531 goto out;
532 }
533 found = 1;
Damien Miller0a80ca12010-02-27 07:55:05 +1100534 }
Damien Miller0a80ca12010-02-27 07:55:05 +1100535 }
536
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000537 if (!found) {
538 if (crit) {
539 error("Certificate critical option \"%s\" "
540 "is not supported", name);
541 goto out;
542 } else {
543 logit("Certificate extension \"%s\" "
544 "is not supported", name);
545 }
markus@openbsd.orgae8b4632015-01-14 10:30:34 +0000546 } else if (sshbuf_len(data) != 0) {
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000547 error("Certificate option \"%s\" corrupt "
Damien Miller0a80ca12010-02-27 07:55:05 +1100548 "(extra data)", name);
549 goto out;
550 }
Darren Tuckera627d422013-06-02 07:31:17 +1000551 free(name);
Damien Millerce986542013-07-18 16:12:44 +1000552 name = NULL;
Damien Miller0a80ca12010-02-27 07:55:05 +1100553 }
Damien Miller4e270b02010-04-16 15:56:21 +1000554 /* successfully parsed all options */
Damien Miller0a80ca12010-02-27 07:55:05 +1100555 ret = 0;
556
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000557 out:
558 if (ret != 0 &&
559 cert_forced_command != NULL &&
560 *cert_forced_command != NULL) {
Darren Tuckera627d422013-06-02 07:31:17 +1000561 free(*cert_forced_command);
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000562 *cert_forced_command = NULL;
563 }
564 if (name != NULL)
Darren Tuckera627d422013-06-02 07:31:17 +1000565 free(name);
markus@openbsd.orgae8b4632015-01-14 10:30:34 +0000566 sshbuf_free(data);
567 sshbuf_free(c);
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000568 return ret;
569}
570
571/*
572 * Set options from critical certificate options. These supersede user key
573 * options so this must be called after auth_parse_options().
574 */
575int
markus@openbsd.orgae8b4632015-01-14 10:30:34 +0000576auth_cert_options(struct sshkey *k, struct passwd *pw)
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000577{
578 int cert_no_port_forwarding_flag = 1;
579 int cert_no_agent_forwarding_flag = 1;
580 int cert_no_x11_forwarding_flag = 1;
581 int cert_no_pty_flag = 1;
582 int cert_no_user_rc = 1;
583 char *cert_forced_command = NULL;
584 int cert_source_address_done = 0;
585
markus@openbsd.orgae8b4632015-01-14 10:30:34 +0000586 if (sshkey_cert_is_legacy(k)) {
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000587 /* All options are in the one field for v00 certs */
markus@openbsd.orgae8b4632015-01-14 10:30:34 +0000588 if (parse_option_list(k->cert->critical, pw,
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000589 OPTIONS_CRITICAL|OPTIONS_EXTENSIONS, 1,
590 &cert_no_port_forwarding_flag,
591 &cert_no_agent_forwarding_flag,
592 &cert_no_x11_forwarding_flag,
593 &cert_no_pty_flag,
594 &cert_no_user_rc,
595 &cert_forced_command,
596 &cert_source_address_done) == -1)
597 return -1;
598 } else {
599 /* Separate options and extensions for v01 certs */
markus@openbsd.orgae8b4632015-01-14 10:30:34 +0000600 if (parse_option_list(k->cert->critical, pw,
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000601 OPTIONS_CRITICAL, 1, NULL, NULL, NULL, NULL, NULL,
602 &cert_forced_command,
603 &cert_source_address_done) == -1)
604 return -1;
markus@openbsd.orgae8b4632015-01-14 10:30:34 +0000605 if (parse_option_list(k->cert->extensions, pw,
djm@openbsd.orgca42c172015-04-22 01:24:01 +0000606 OPTIONS_EXTENSIONS, 0,
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000607 &cert_no_port_forwarding_flag,
608 &cert_no_agent_forwarding_flag,
609 &cert_no_x11_forwarding_flag,
610 &cert_no_pty_flag,
611 &cert_no_user_rc,
612 NULL, NULL) == -1)
613 return -1;
614 }
615
Damien Miller0a80ca12010-02-27 07:55:05 +1100616 no_port_forwarding_flag |= cert_no_port_forwarding_flag;
617 no_agent_forwarding_flag |= cert_no_agent_forwarding_flag;
618 no_x11_forwarding_flag |= cert_no_x11_forwarding_flag;
619 no_pty_flag |= cert_no_pty_flag;
620 no_user_rc |= cert_no_user_rc;
621 /* CA-specified forced command supersedes key option */
622 if (cert_forced_command != NULL) {
623 if (forced_command != NULL)
Darren Tuckera627d422013-06-02 07:31:17 +1000624 free(forced_command);
Damien Miller0a80ca12010-02-27 07:55:05 +1100625 forced_command = cert_forced_command;
626 }
Damien Millerd0e4a8e2010-05-21 14:58:32 +1000627 return 0;
Damien Miller0a80ca12010-02-27 07:55:05 +1100628}
629