1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
23 */
24
25 #include <nss_dbdefs.h>
26 #include <pwd.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <syslog.h>
30 #include <unistd.h>
31 #include <auth_attr.h>
32 #include <deflt.h>
33 #include <priv.h>
34 #include <secdb.h>
35 #include <user_attr.h>
36 #include <sys/task.h>
37 #include <libintl.h>
38 #include <project.h>
39 #include <errno.h>
40 #include <alloca.h>
41
42 #include <bsm/adt.h>
43 #include <bsm/adt_event.h> /* adt_get_auid() */
44
45 #include <security/pam_appl.h>
46 #include <security/pam_modules.h>
47 #include <security/pam_impl.h>
48
49 #define PROJECT "project="
50 #define PROJSZ (sizeof (PROJECT) - 1)
51
52 /*
53 * unix_cred - PAM auth modules must contain both pam_sm_authenticate
54 * and pam_sm_setcred. Some other auth module is responsible
55 * for authentication (e.g., pam_unix_auth.so), this module
56 * only implements pam_sm_setcred so that the authentication
57 * can be separated without knowledge of the Solaris Unix style
58 * credential setting.
59 * Solaris Unix style credential setting includes initializing
60 * the audit characteristics if not already initialized and
61 * setting the user's default and limit privileges.
62 */
63
64 /*
65 * unix_cred - pam_sm_authenticate
66 *
67 * Returns PAM_IGNORE.
68 */
69
70 /*ARGSUSED*/
71 int
72 pam_sm_authenticate(pam_handle_t *pamh, int flags, int argc, const char **argv)
73 {
74 return (PAM_IGNORE);
75 }
76
77 /*
78 * Set the privilege set. The attributes are enumerated by _enum_attrs,
79 * including the attribues user_attr, prof_attr and policy.conf
80 */
81 static int
82 getset(char *str, priv_set_t **res)
83 {
84 priv_set_t *tmp;
85 char *badp;
86 int len;
87
88 if (str == NULL)
89 return (0);
90
91 len = strlen(str) + 1;
92 badp = alloca(len);
93 (void) memset(badp, '\0', len);
94 do {
95 const char *q, *endp;
96 tmp = priv_str_to_set(str, ",", &endp);
97 if (tmp == NULL) {
98 if (endp == NULL)
99 break;
100
101 /* Now remove the bad privilege endp points to */
102 q = strchr(endp, ',');
103 if (q == NULL)
104 q = endp + strlen(endp);
105
106 if (*badp != '\0')
107 (void) strlcat(badp, ",", len);
108 /* Memset above guarantees NUL termination */
109 /* LINTED */
110 (void) strncat(badp, endp, q - endp);
111 /* excise bad privilege; strtok ignores 2x sep */
112 (void) memmove((void *)endp, q, strlen(q) + 1);
113 }
114 } while (tmp == NULL && *str != '\0');
115
116 if (tmp == NULL) {
117 syslog(LOG_AUTH|LOG_ERR,
118 "pam_setcred: can't parse privilege specification: %m\n");
119 return (-1);
120 } else if (*badp != '\0') {
121 syslog(LOG_AUTH|LOG_DEBUG,
122 "pam_setcred: unrecognized privilege(s): %s\n", badp);
123 }
124 *res = tmp;
125 return (0);
126 }
127
128 typedef struct deflim {
129 char *def;
130 char *lim;
131 } deflim_t;
132
133 /*ARGSUSED*/
134 static int
135 finddeflim(const char *name, kva_t *kva, void *ctxt, void *pres)
136 {
137 deflim_t *pdef = pres;
138 char *val;
139
140 if (pdef->def == NULL) {
141 val = kva_match(kva, USERATTR_DFLTPRIV_KW);
142 if (val != NULL)
143 pdef->def = strdup(val);
144 }
145 if (pdef->lim == NULL) {
146 val = kva_match(kva, USERATTR_LIMPRIV_KW);
147 if (val != NULL)
148 pdef->lim = strdup(val);
149 }
150 return (pdef->lim != NULL && pdef->def != NULL);
151 }
152
153 /*
154 * unix_cred - pam_sm_setcred
155 *
156 * Entry flags = PAM_ESTABLISH_CRED, set up Solaris Unix cred.
157 * PAM_DELETE_CRED, NOP, return PAM_SUCCESS.
158 * PAM_REINITIALIZE_CRED, set up Solaris Unix cred,
159 * or merge the current context with the new
160 * user.
161 * PAM_REFRESH_CRED, set up Solaris Unix cred.
162 * PAM_SILENT, print no messages to user.
163 *
164 * Returns PAM_SUCCESS, if all successful.
165 * PAM_CRED_ERR, if unable to set credentials.
166 * PAM_USER_UNKNOWN, if PAM_USER not set, or unable to find
167 * user in databases.
168 * PAM_SYSTEM_ERR, if no valid flag, or unable to get/set
169 * user's audit state.
170 */
171
172 int
173 pam_sm_setcred(pam_handle_t *pamh, int flags, int argc, const char **argv)
174 {
175 int i;
176 int debug = 0;
177 uint_t nowarn = flags & PAM_SILENT;
178 int ret = PAM_SUCCESS;
179 char *user;
180 char *auser;
181 char *rhost;
182 char *tty;
183 au_id_t auid;
184 adt_session_data_t *ah;
185 adt_termid_t *termid = NULL;
186 priv_set_t *lim, *def, *tset;
187 char messages[PAM_MAX_NUM_MSG][PAM_MAX_MSG_SIZE];
188 char buf[PROJECT_BUFSZ];
189 struct project proj, *pproj;
190 int error;
191 char *projname;
192 char *kvs;
193 struct passwd pwd;
194 char pwbuf[NSS_BUFLEN_PASSWD];
195 deflim_t deflim;
196
197 for (i = 0; i < argc; i++) {
198 if (strcmp(argv[i], "debug") == 0)
199 debug = 1;
200 else if (strcmp(argv[i], "nowarn") == 0)
201 nowarn |= 1;
202 }
203
204 if (debug)
205 syslog(LOG_AUTH | LOG_DEBUG,
206 "pam_unix_cred: pam_sm_setcred(flags = %x, argc= %d)",
207 flags, argc);
208
209 (void) pam_get_item(pamh, PAM_USER, (void **)&user);
210
211 if (user == NULL || *user == '\0') {
212 syslog(LOG_AUTH | LOG_ERR,
213 "pam_unix_cred: USER NULL or empty!\n");
214 return (PAM_USER_UNKNOWN);
215 }
216 (void) pam_get_item(pamh, PAM_AUSER, (void **)&auser);
217 (void) pam_get_item(pamh, PAM_RHOST, (void **)&rhost);
218 (void) pam_get_item(pamh, PAM_TTY, (void **)&tty);
219 if (debug)
220 syslog(LOG_AUTH | LOG_DEBUG,
221 "pam_unix_cred: user = %s, auser = %s, rhost = %s, "
222 "tty = %s", user,
223 (auser == NULL) ? "NULL" : (*auser == '\0') ? "ZERO" :
224 auser,
225 (rhost == NULL) ? "NULL" : (*rhost == '\0') ? "ZERO" :
226 rhost,
227 (tty == NULL) ? "NULL" : (*tty == '\0') ? "ZERO" :
228 tty);
229
230 /* validate flags */
231 switch (flags & (PAM_ESTABLISH_CRED | PAM_DELETE_CRED |
232 PAM_REINITIALIZE_CRED | PAM_REFRESH_CRED)) {
233 case 0:
234 /* set default flag */
235 flags |= PAM_ESTABLISH_CRED;
236 break;
237 case PAM_ESTABLISH_CRED:
238 case PAM_REINITIALIZE_CRED:
239 case PAM_REFRESH_CRED:
240 break;
241 case PAM_DELETE_CRED:
242 return (PAM_SUCCESS);
243 default:
244 syslog(LOG_AUTH | LOG_ERR,
245 "pam_unix_cred: invalid flags %x", flags);
246 return (PAM_SYSTEM_ERR);
247 }
248
249 /*
250 * if auditing on and process audit state not set,
251 * setup audit context for process.
252 */
253 if (adt_start_session(&ah, NULL, ADT_USE_PROC_DATA) != 0) {
254 syslog(LOG_AUTH | LOG_ERR,
255 "pam_unix_cred: cannot create start audit session %m");
256 return (PAM_SYSTEM_ERR);
257 }
258 adt_get_auid(ah, &auid);
259 if (debug) {
260 int auditstate;
261
262 if (auditon(A_GETCOND, (caddr_t)&auditstate,
263 sizeof (auditstate)) != 0) {
264 auditstate = AUC_DISABLED;
265 }
266 syslog(LOG_AUTH | LOG_DEBUG,
267 "pam_unix_cred: state = %d, auid = %d", auditstate,
268 auid);
269 }
270 if (getpwnam_r(user, &pwd, pwbuf, sizeof (pwbuf)) == NULL) {
271 syslog(LOG_AUTH | LOG_ERR,
272 "pam_unix_cred: cannot get passwd entry for user = %s",
273 user);
274 ret = PAM_USER_UNKNOWN;
275 goto adt_done;
276 }
277
278 if ((auid == AU_NOAUDITID) &&
279 (flags & PAM_ESTABLISH_CRED)) {
280 struct passwd apwd;
281 char apwbuf[NSS_BUFLEN_PASSWD];
282
283 errno = 0;
284 if ((rhost == NULL || *rhost == '\0')) {
285 if (adt_load_ttyname(tty, &termid) != 0) {
286 if (errno == ENETDOWN) {
287 /*
288 * tolerate not being able to
289 * translate local hostname
290 * to a termid -- it will be
291 * "loopback".
292 */
293 syslog(LOG_AUTH | LOG_ERR,
294 "pam_unix_cred: cannot load "
295 "ttyname: %m, continuing.");
296 goto adt_setuser;
297 } else if (errno != 0) {
298 syslog(LOG_AUTH | LOG_ERR,
299 "pam_unix_cred: cannot load "
300 "ttyname: %m.");
301 } else {
302 syslog(LOG_AUTH | LOG_ERR,
303 "pam_unix_cred: cannot load "
304 "ttyname.");
305 }
306 ret = PAM_SYSTEM_ERR;
307 goto adt_done;
308 }
309 } else {
310 if (adt_load_hostname(rhost, &termid) != 0) {
311 if (errno != 0) {
312 syslog(LOG_AUTH | LOG_ERR,
313 "pam_unix_cred: cannot load "
314 "hostname: %m.");
315 } else {
316 syslog(LOG_AUTH | LOG_ERR,
317 "pam_unix_cred: cannot load "
318 "hostname.");
319 }
320 ret = PAM_SYSTEM_ERR;
321 goto adt_done;
322 }
323 }
324 adt_setuser:
325 if ((auser != NULL) && (*auser != '\0') &&
326 (getpwnam_r(auser, &apwd, apwbuf,
327 sizeof (apwbuf)) != NULL)) {
328 /*
329 * set up the initial audit for user coming
330 * from another user
331 */
332 if (adt_set_user(ah, apwd.pw_uid, apwd.pw_gid,
333 apwd.pw_uid, apwd.pw_gid, termid, ADT_NEW) != 0) {
334 syslog(LOG_AUTH | LOG_ERR,
335 "pam_unix_cred: cannot set auser audit "
336 "%m");
337 ret = PAM_SYSTEM_ERR;
338 goto adt_done;
339 }
340 if (adt_set_user(ah, pwd.pw_uid, pwd.pw_gid,
341 pwd.pw_uid, pwd.pw_gid, NULL,
342 ADT_UPDATE) != 0) {
343 syslog(LOG_AUTH | LOG_ERR,
344 "pam_unix_cred: cannot merge user audit "
345 "%m");
346 ret = PAM_SYSTEM_ERR;
347 goto adt_done;
348 }
349 if (debug) {
350 syslog(LOG_AUTH | LOG_DEBUG,
351 "pam_unix_cred: new audit set for %d:%d",
352 apwd.pw_uid, pwd.pw_uid);
353 }
354 } else {
355 /*
356 * No authenticated user or authenticated user is
357 * not a local user, no remote attribution, set
358 * up the initial audit as for direct user login
359 */
360 if (adt_set_user(ah, pwd.pw_uid, pwd.pw_gid,
361 pwd.pw_uid, pwd.pw_gid, termid, ADT_NEW) != 0) {
362 syslog(LOG_AUTH | LOG_ERR,
363 "pam_unix_cred: cannot set user audit %m");
364 ret = PAM_SYSTEM_ERR;
365 goto adt_done;
366 }
367 }
368 if (adt_set_proc(ah) != 0) {
369 syslog(LOG_AUTH | LOG_ERR,
370 "pam_unix_cred: cannot set process audit %m");
371 ret = PAM_CRED_ERR;
372 goto adt_done;
373 }
374 if (debug) {
375 syslog(LOG_AUTH | LOG_DEBUG,
376 "pam_unix_cred: new audit set for %d",
377 pwd.pw_uid);
378 }
379 } else if ((auid != AU_NOAUDITID) &&
380 (flags & PAM_REINITIALIZE_CRED)) {
381 if (adt_set_user(ah, pwd.pw_uid, pwd.pw_gid, pwd.pw_uid,
382 pwd.pw_gid, NULL, ADT_UPDATE) != 0) {
383 syslog(LOG_AUTH | LOG_ERR,
384 "pam_unix_cred: cannot set user audit %m");
385 ret = PAM_SYSTEM_ERR;
386 goto adt_done;
387 }
388 if (adt_set_proc(ah) != 0) {
389 syslog(LOG_AUTH | LOG_ERR,
390 "pam_unix_cred: cannot set process audit %m");
391 ret = PAM_CRED_ERR;
392 goto adt_done;
393 }
394 if (debug) {
395 syslog(LOG_AUTH | LOG_DEBUG,
396 "pam_unix_cred: audit merged for %d:%d",
397 auid, pwd.pw_uid);
398 }
399 } else if (debug) {
400 syslog(LOG_AUTH | LOG_DEBUG,
401 "pam_unix_cred: audit already set for %d", auid);
402 }
403 adt_done:
404 if (termid != NULL)
405 free(termid);
406 if (adt_end_session(ah) != 0) {
407 syslog(LOG_AUTH | LOG_ERR,
408 "pam_unix_cred: unable to end audit session");
409 }
410
411 if (ret != PAM_SUCCESS)
412 return (ret);
413
414 /* Initialize the user's project */
415 (void) pam_get_item(pamh, PAM_RESOURCE, (void **)&kvs);
416 if (kvs != NULL) {
417 char *tmp, *lasts, *tok;
418
419 kvs = tmp = strdup(kvs);
420 if (kvs == NULL)
421 return (PAM_BUF_ERR);
422
423 while ((tok = strtok_r(tmp, ";", &lasts)) != NULL) {
424 if (strncmp(tok, PROJECT, PROJSZ) == 0) {
425 projname = tok + PROJSZ;
426 break;
427 }
428 tmp = NULL;
429 }
430 } else {
431 projname = NULL;
432 }
433
434 if (projname == NULL || *projname == '\0') {
435 pproj = getdefaultproj(user, &proj, (void *)&buf,
436 PROJECT_BUFSZ);
437 } else {
438 pproj = getprojbyname(projname, &proj, (void *)&buf,
439 PROJECT_BUFSZ);
440 }
441 /* projname points into kvs, so this is the first opportunity to free */
442 if (kvs != NULL)
443 free(kvs);
444 if (pproj == NULL) {
445 syslog(LOG_AUTH | LOG_ERR,
446 "pam_unix_cred: no default project for user %s", user);
447 if (!nowarn) {
448 (void) snprintf(messages[0], sizeof (messages[0]),
449 dgettext(TEXT_DOMAIN, "No default project!"));
450 (void) __pam_display_msg(pamh, PAM_ERROR_MSG,
451 1, messages, NULL);
452 }
453 return (PAM_SYSTEM_ERR);
454 }
455 if ((error = setproject(proj.pj_name, user, TASK_NORMAL)) != 0) {
456 kva_t *kv_array;
457
458 switch (error) {
459 case SETPROJ_ERR_TASK:
460 if (errno == EAGAIN) {
461 syslog(LOG_AUTH | LOG_ERR,
462 "pam_unix_cred: project \"%s\" resource "
463 "control limit has been reached",
464 proj.pj_name);
465 (void) snprintf(messages[0],
466 sizeof (messages[0]), dgettext(
467 TEXT_DOMAIN,
468 "Resource control limit has been "
469 "reached"));
470 } else {
471 syslog(LOG_AUTH | LOG_ERR,
472 "pam_unix_cred: user %s could not join "
473 "project \"%s\": %m", user, proj.pj_name);
474 (void) snprintf(messages[0],
475 sizeof (messages[0]), dgettext(
476 TEXT_DOMAIN,
477 "Could not join default project"));
478 }
479 if (!nowarn)
480 (void) __pam_display_msg(pamh, PAM_ERROR_MSG, 1,
481 messages, NULL);
482 break;
483 case SETPROJ_ERR_POOL:
484 (void) snprintf(messages[0], sizeof (messages[0]),
485 dgettext(TEXT_DOMAIN,
486 "Could not bind to resource pool"));
487 switch (errno) {
488 case EACCES:
489 syslog(LOG_AUTH | LOG_ERR,
490 "pam_unix_cred: project \"%s\" could not "
491 "bind to resource pool: No resource pool "
492 "accepting default bindings exists",
493 proj.pj_name);
494 (void) snprintf(messages[1],
495 sizeof (messages[1]),
496 dgettext(TEXT_DOMAIN,
497 "No resource pool accepting "
498 "default bindings exists"));
499 break;
500 case ESRCH:
501 syslog(LOG_AUTH | LOG_ERR,
502 "pam_unix_cred: project \"%s\" could not "
503 "bind to resource pool: The resource pool "
504 "is unknown", proj.pj_name);
505 (void) snprintf(messages[1],
506 sizeof (messages[1]),
507 dgettext(TEXT_DOMAIN,
508 "The specified resource pool "
509 "is unknown"));
510 break;
511 default:
512 (void) snprintf(messages[1],
513 sizeof (messages[1]),
514 dgettext(TEXT_DOMAIN,
515 "Failure during pool binding"));
516 syslog(LOG_AUTH | LOG_ERR,
517 "pam_unix_cred: project \"%s\" could not "
518 "bind to resource pool: %m", proj.pj_name);
519 }
520 if (!nowarn)
521 (void) __pam_display_msg(pamh, PAM_ERROR_MSG,
522 2, messages, NULL);
523 break;
524 default:
525 /*
526 * Resource control assignment failed. Unlike
527 * newtask(1m), we treat this as an error.
528 */
529 if (error < 0) {
530 /*
531 * This isn't supposed to happen, but in
532 * case it does, this error message
533 * doesn't use error as an index, like
534 * the others might.
535 */
536 syslog(LOG_AUTH | LOG_ERR,
537 "pam_unix_cred: unkwown error joining "
538 "project \"%s\" (%d)", proj.pj_name, error);
539 (void) snprintf(messages[0],
540 sizeof (messages[0]),
541 dgettext(TEXT_DOMAIN,
542 "unkwown error joining project \"%s\""
543 " (%d)"), proj.pj_name, error);
544 } else if ((kv_array = _str2kva(proj.pj_attr, KV_ASSIGN,
545 KV_DELIMITER)) != NULL) {
546 syslog(LOG_AUTH | LOG_ERR,
547 "pam_unix_cred: %s resource control "
548 "assignment failed for project \"%s\"",
549 kv_array->data[error - 1].key,
550 proj.pj_name);
551 (void) snprintf(messages[0],
552 sizeof (messages[0]),
553 dgettext(TEXT_DOMAIN,
554 "%s resource control assignment failed for "
555 "project \"%s\""),
556 kv_array->data[error - 1].key,
557 proj.pj_name);
558 _kva_free(kv_array);
559 } else {
560 syslog(LOG_AUTH | LOG_ERR,
561 "pam_unix_cred: resource control "
562 "assignment failed for project \"%s\""
563 "attribute %d", proj.pj_name, error);
564 (void) snprintf(messages[0],
565 sizeof (messages[0]),
566 dgettext(TEXT_DOMAIN,
567 "resource control assignment failed for "
568 "project \"%s\" attribute %d"),
569 proj.pj_name, error);
570 }
571 if (!nowarn)
572 (void) __pam_display_msg(pamh, PAM_ERROR_MSG,
573 1, messages, NULL);
574 }
575 return (PAM_SYSTEM_ERR);
576 }
577
578 tset = def = lim = NULL;
579 deflim.def = deflim.lim = NULL;
580
581 (void) _enum_attrs(user, finddeflim, NULL, &deflim);
582
583 if (getset(deflim.lim, &lim) != 0 || getset(deflim.def, &def) != 0) {
584 ret = PAM_SYSTEM_ERR;
585 goto out;
586 }
587
588 if (def == NULL) {
589 def = priv_allocset();
590 if (def == NULL) {
591 ret = PAM_SYSTEM_ERR;
592 goto out;
593 }
594 priv_basicset(def);
595 (void) priv_addset(def, PRIV_PROC_SECFLAGS);
596 errno = 0;
597 if ((pathconf("/", _PC_CHOWN_RESTRICTED) == -1) && (errno == 0))
598 (void) priv_addset(def, PRIV_FILE_CHOWN_SELF);
599 }
600 /*
601 * Silently limit the privileges to those actually available
602 * in the current zone.
603 */
604 tset = priv_allocset();
605 if (tset == NULL) {
606 ret = PAM_SYSTEM_ERR;
607 goto out;
608 }
609 if (getppriv(PRIV_PERMITTED, tset) != 0) {
610 ret = PAM_SYSTEM_ERR;
611 goto out;
612 }
613 if (!priv_issubset(def, tset))
614 priv_intersect(tset, def);
615 /*
616 * We set privilege awareness here so that I gets copied to
617 * P & E when the final setuid(uid) happens.
618 */
619 (void) setpflags(PRIV_AWARE, 1);
620 if (setppriv(PRIV_SET, PRIV_INHERITABLE, def) != 0) {
621 syslog(LOG_AUTH | LOG_ERR,
622 "pam_setcred: setppriv(defaultpriv) failed: %m");
623 ret = PAM_CRED_ERR;
624 }
625
626 if (lim != NULL) {
627 /*
628 * Silently limit the privileges to the limit set available.
629 */
630 if (getppriv(PRIV_LIMIT, tset) != 0) {
631 ret = PAM_SYSTEM_ERR;
632 goto out;
633 }
634 if (!priv_issubset(lim, tset))
635 priv_intersect(tset, lim);
636 if (setppriv(PRIV_SET, PRIV_LIMIT, lim) != 0) {
637 syslog(LOG_AUTH | LOG_ERR,
638 "pam_setcred: setppriv(limitpriv) failed: %m");
639 ret = PAM_CRED_ERR;
640 goto out;
641 }
642 /*
643 * In order not to surprise certain applications, we
644 * need to get rid of privilege awareness and thus we must
645 * set this flag which will cause a reset on set*uid().
646 */
647 (void) setpflags(PRIV_AWARE_RESET, 1);
648 }
649 /*
650 * This may fail but we do not care as this will be reset later
651 * when the uids are set to their final values.
652 */
653 (void) setpflags(PRIV_AWARE, 0);
654 /*
655 * Remove PRIV_PFEXEC; stop running as if we are under a profile
656 * shell. A user with a profile shell will set PRIV_PFEXEC.
657 */
658 (void) setpflags(PRIV_PFEXEC, 0);
659
660 out:
661 free(deflim.lim);
662 free(deflim.def);
663
664 if (lim != NULL)
665 priv_freeset(lim);
666 if (def != NULL)
667 priv_freeset(def);
668 if (tset != NULL)
669 priv_freeset(tset);
670
671 return (ret);
672 }