blob: 9f36db065ff26346529e7ce265a12a25bbccd9f0 [file] [log] [blame]
paul01245822003-05-20 01:22:17 +00001/*
2 * Zebra privileges.
3 *
4 * Copyright (C) 2003 Paul Jakma.
paulceacedb2005-09-29 14:39:32 +00005 * Copyright (C) 2005 Sun Microsystems, Inc.
paul01245822003-05-20 01:22:17 +00006 *
7 * This file is part of GNU Zebra.
8 *
9 * GNU Zebra is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License as published by the
11 * Free Software Foundation; either version 2, or (at your option) any
12 * later version.
13 *
14 * GNU Zebra is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with GNU Zebra; see the file COPYING. If not, write to the Free
21 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
22 * 02111-1307, USA.
23 */
paul01245822003-05-20 01:22:17 +000024#include <zebra.h>
25#include "log.h"
26#include "privs.h"
27#include "memory.h"
paul01245822003-05-20 01:22:17 +000028
paulceacedb2005-09-29 14:39:32 +000029#ifdef HAVE_CAPABILITIES
30/* sort out some generic internal types for:
31 *
32 * privilege values (cap_value_t, priv_t) -> pvalue_t
33 * privilege set (..., priv_set_t) -> pset_t
34 * privilege working storage (cap_t, ...) -> pstorage_t
35 *
36 * values we think of as numeric (they're ints really, but we dont know)
37 * sets are mostly opaque, to hold a set of privileges, related in some way.
38 * storage binds together a set of sets we're interested in.
39 * (in reality: cap_value_t and priv_t are ints)
40 */
41#ifdef HAVE_LCAPS
42/* Linux doesn't have a 'set' type: a set of related privileges */
43struct _pset {
44 int num;
45 cap_value_t *caps;
46};
47typedef cap_value_t pvalue_t;
48typedef struct _pset pset_t;
49typedef cap_t pstorage_t;
50
51#elif defined (HAVE_SOLARIS_CAPABILITIES)
52typedef priv_t pvalue_t;
53typedef priv_set_t pset_t;
54typedef priv_set_t *pstorage_t;
55#else /* neither LCAPS nor SOLARIS_CAPABILITIES */
56#error "HAVE_CAPABILITIES defined, but neither LCAPS nor Solaris Capabilties!"
57#endif /* HAVE_LCAPS */
58#endif /* HAVE_CAPABILITIES */
59
60/* the default NULL state we report is RAISED, but could be LOWERED if
61 * zprivs_terminate is called and the NULL handler is installed.
62 */
63static zebra_privs_current_t zprivs_null_state = ZPRIVS_RAISED;
64
paul01245822003-05-20 01:22:17 +000065/* internal privileges state */
66static struct _zprivs_t
67{
paulceacedb2005-09-29 14:39:32 +000068#ifdef HAVE_CAPABILITIES
69 pstorage_t caps; /* working storage */
70 pset_t *syscaps_p; /* system-type requested permitted caps */
71 pset_t *syscaps_i; /* system-type requested inheritable caps */
72#endif /* HAVE_CAPABILITIES */
paul01245822003-05-20 01:22:17 +000073 uid_t zuid, /* uid to run as */
74 zsuid; /* saved uid */
75 gid_t zgid; /* gid to run as */
hassoba3a0bc2003-06-04 17:41:54 +000076 gid_t vtygrp; /* gid for vty sockets */
paul01245822003-05-20 01:22:17 +000077} zprivs_state;
78
79/* externally exported but not directly accessed functions */
paulceacedb2005-09-29 14:39:32 +000080#ifdef HAVE_CAPABILITIES
paul01245822003-05-20 01:22:17 +000081int zprivs_change_caps (zebra_privs_ops_t);
82zebra_privs_current_t zprivs_state_caps (void);
paulceacedb2005-09-29 14:39:32 +000083#endif /* HAVE_CAPABILITIES */
paul01245822003-05-20 01:22:17 +000084int zprivs_change_uid (zebra_privs_ops_t);
85zebra_privs_current_t zprivs_state_uid (void);
86int zprivs_change_null (zebra_privs_ops_t);
87zebra_privs_current_t zprivs_state_null (void);
paul01245822003-05-20 01:22:17 +000088
paulceacedb2005-09-29 14:39:32 +000089#ifdef HAVE_CAPABILITIES
90/* internal capability API */
91static pset_t *zcaps2sys (zebra_capabilities_t *, int);
92static void zprivs_caps_init (struct zebra_privs_t *);
93static void zprivs_caps_terminate (void);
94
95/* Map of Quagga abstract capabilities to system capabilities */
96static struct
paul01245822003-05-20 01:22:17 +000097{
paulceacedb2005-09-29 14:39:32 +000098 int num;
99 pvalue_t *system_caps;
100} cap_map [ZCAP_MAX] =
101{
102#ifdef HAVE_LCAPS /* Quagga -> Linux capabilities mappings */
103 [ZCAP_SETID] = { 2, (pvalue_t []) { CAP_SETGID,
104 CAP_SETUID }, },
105 [ZCAP_BIND] = { 2, (pvalue_t []) { CAP_NET_BIND_SERVICE,
106 CAP_NET_BROADCAST }, },
107 [ZCAP_NET_ADMIN] = { 1, (pvalue_t []) { CAP_NET_ADMIN }, },
108 [ZCAP_NET_RAW] = { 1, (pvalue_t []) { CAP_NET_RAW }, },
109 [ZCAP_CHROOT] = { 1, (pvalue_t []) { CAP_SYS_CHROOT, }, },
110 [ZCAP_NICE] = { 1, (pvalue_t []) { CAP_SYS_NICE }, },
111 [ZCAP_PTRACE] = { 1, (pvalue_t []) { CAP_SYS_PTRACE }, },
112 [ZCAP_DAC_OVERRIDE] = { 1, (pvalue_t []) { CAP_DAC_OVERRIDE }, },
113 [ZCAP_READ_SEARCH] = { 1, (pvalue_t []) { CAP_DAC_READ_SEARCH }, },
114 [ZCAP_SYS_ADMIN] = { 1, (pvalue_t []) { CAP_SYS_ADMIN }, },
115 [ZCAP_FOWNER] = { 1, (pvalue_t []) { CAP_FOWNER }, },
116#elif defined(HAVE_SOLARIS_CAPABILITIES) /* HAVE_LCAPS */
117 /* Quagga -> Solaris privilege mappings */
118 [ZCAP_SETID] = { 1, (pvalue_t []) { PRIV_PROC_SETID }, },
119 [ZCAP_BIND] = { 1, (pvalue_t []) { PRIV_NET_PRIVADDR }, },
120 [ZCAP_NET_ADMIN] = { 1, (pvalue_t []) { PRIV_SYS_NET_CONFIG }, },
121 [ZCAP_NET_RAW] = { 2, (pvalue_t []) { PRIV_NET_RAWACCESS,
122 PRIV_NET_ICMPACCESS }, },
123 [ZCAP_CHROOT] = { 1, (pvalue_t []) { PRIV_PROC_CHROOT }, },
124 [ZCAP_NICE] = { 1, (pvalue_t []) { PRIV_PROC_PRIOCNTL }, },
125 [ZCAP_PTRACE] = { 1, (pvalue_t []) { PRIV_PROC_SESSION }, },
126 [ZCAP_DAC_OVERRIDE] = { 2, (pvalue_t []) { PRIV_FILE_DAC_EXECUTE,
127 PRIV_FILE_DAC_READ,
128 PRIV_FILE_DAC_SEARCH,
129 PRIV_FILE_DAC_WRITE,
130 PRIV_FILE_DAC_SEARCH }, },
131 [ZCAP_READ_SEARCH] = { 2, (pvalue_t []) { PRIV_FILE_DAC_SEARCH,
132 PRIV_FILE_DAC_READ }, },
133 [ZCAP_SYS_ADMIN] = { 1, (pvalue_t []) { PRIV_SYS_ADMIN }, },
134 [ZCAP_FOWNER] = { 1, (pvalue_t []) { PRIV_FILE_OWNER }, },
135#endif /* HAVE_SOLARIS_CAPABILITIES */
paul01245822003-05-20 01:22:17 +0000136};
paulceacedb2005-09-29 14:39:32 +0000137
138#ifdef HAVE_LCAPS
139/* Linux forms of capabilities methods */
paul01245822003-05-20 01:22:17 +0000140/* convert zebras privileges to system capabilities */
paulceacedb2005-09-29 14:39:32 +0000141static pset_t *
paul01245822003-05-20 01:22:17 +0000142zcaps2sys (zebra_capabilities_t *zcaps, int num)
143{
paulceacedb2005-09-29 14:39:32 +0000144 pset_t *syscaps;
145 int i, j = 0, count = 0;
paul01245822003-05-20 01:22:17 +0000146
147 if (!num)
148 return NULL;
paulceacedb2005-09-29 14:39:32 +0000149
150 /* first count up how many system caps we have */
151 for (i= 0; i < num; i++)
152 count += cap_map[zcaps[i]].num;
153
154 if ( (syscaps = XCALLOC (MTYPE_PRIVS, (sizeof(pset_t) * num))) == NULL)
paul01245822003-05-20 01:22:17 +0000155 {
paulceacedb2005-09-29 14:39:32 +0000156 fprintf (stderr, "%s: could not allocate syscaps!", __func__);
paul01245822003-05-20 01:22:17 +0000157 return NULL;
158 }
159
paulceacedb2005-09-29 14:39:32 +0000160 syscaps->caps = XCALLOC (MTYPE_PRIVS, (sizeof (pvalue_t) * count));
161
162 if (!syscaps->caps)
paul01245822003-05-20 01:22:17 +0000163 {
paulceacedb2005-09-29 14:39:32 +0000164 fprintf (stderr, "%s: could not XCALLOC caps!", __func__);
165 return NULL;
paul01245822003-05-20 01:22:17 +0000166 }
paulceacedb2005-09-29 14:39:32 +0000167
168 /* copy the capabilities over */
169 count = 0;
170 for (i=0; i < num; i++)
171 for (j = 0; j < cap_map[zcaps[i]].num; j++)
172 syscaps->caps[count++] = cap_map[zcaps[i]].system_caps[j];
173
174 /* iterations above should be exact same as previous count, obviously.. */
175 syscaps->num = count;
176
paul01245822003-05-20 01:22:17 +0000177 return syscaps;
178}
179
180/* set or clear the effective capabilities to/from permitted */
181int
182zprivs_change_caps (zebra_privs_ops_t op)
183{
184 cap_flag_value_t cflag;
185
paulceacedb2005-09-29 14:39:32 +0000186 /* should be no possibility of being called without valid caps */
187 assert (zprivs_state.syscaps_p && zprivs_state.caps);
188 if (! (zprivs_state.syscaps_p && zprivs_state.caps))
189 exit (1);
190
paul01245822003-05-20 01:22:17 +0000191 if (op == ZPRIVS_RAISE)
192 cflag = CAP_SET;
193 else if (op == ZPRIVS_LOWER)
194 cflag = CAP_CLEAR;
195 else
196 return -1;
197
198 if ( !cap_set_flag (zprivs_state.caps, CAP_EFFECTIVE,
paulceacedb2005-09-29 14:39:32 +0000199 zprivs_state.syscaps_p->num,
200 zprivs_state.syscaps_p->caps,
201 cflag))
paul01245822003-05-20 01:22:17 +0000202 return cap_set_proc (zprivs_state.caps);
203 return -1;
204}
205
206zebra_privs_current_t
207zprivs_state_caps (void)
208{
209 int i;
paul01245822003-05-20 01:22:17 +0000210 cap_flag_value_t val;
paulceacedb2005-09-29 14:39:32 +0000211
212 /* should be no possibility of being called without valid caps */
213 assert (zprivs_state.syscaps_p && zprivs_state.caps);
214 if (! (zprivs_state.syscaps_p && zprivs_state.caps))
215 exit (1);
paul01245822003-05-20 01:22:17 +0000216
paulceacedb2005-09-29 14:39:32 +0000217 for (i=0; i < zprivs_state.syscaps_p->num; i++)
paul01245822003-05-20 01:22:17 +0000218 {
paulceacedb2005-09-29 14:39:32 +0000219 if ( cap_get_flag (zprivs_state.caps, zprivs_state.syscaps_p->caps[i],
paul01245822003-05-20 01:22:17 +0000220 CAP_EFFECTIVE, &val) )
paulceacedb2005-09-29 14:39:32 +0000221 {
222 zlog_warn ("zprivs_state_caps: could not cap_get_flag, %s",
223 safe_strerror (errno) );
224 return ZPRIVS_UNKNOWN;
225 }
paul01245822003-05-20 01:22:17 +0000226 if (val == CAP_SET)
paul33b72942003-05-20 02:22:42 +0000227 return ZPRIVS_RAISED;
paul01245822003-05-20 01:22:17 +0000228 }
229 return ZPRIVS_LOWERED;
230}
231
paulceacedb2005-09-29 14:39:32 +0000232static void
233zprivs_caps_init (struct zebra_privs_t *zprivs)
234{
235 zprivs_state.syscaps_p = zcaps2sys (zprivs->caps_p, zprivs->cap_num_p);
236 zprivs_state.syscaps_i = zcaps2sys (zprivs->caps_i, zprivs->cap_num_i);
paul01245822003-05-20 01:22:17 +0000237
paulceacedb2005-09-29 14:39:32 +0000238 /* Tell kernel we want caps maintained across uid changes */
239 if ( prctl(PR_SET_KEEPCAPS, 1, 0, 0, 0) == -1 )
240 {
241 fprintf (stderr, "privs_init: could not set PR_SET_KEEPCAPS, %s\n",
242 safe_strerror (errno) );
243 exit(1);
244 }
245
246 if ( !zprivs_state.syscaps_p )
247 {
248 fprintf (stderr, "privs_init: capabilities enabled, "
249 "but no capabilities supplied\n");
250 }
251
252 if ( !(zprivs_state.caps = cap_init()) )
253 {
254 fprintf (stderr, "privs_init: failed to cap_init, %s\n",
255 safe_strerror (errno));
256 exit (1);
257 }
258
259 /* we have caps, we have no need to ever change back the original user */
260 if (zprivs_state.zuid)
261 {
262 if ( setreuid (zprivs_state.zuid, zprivs_state.zuid) )
263 {
264 fprintf (stderr, "zprivs_init (cap): could not setreuid, %s\n",
265 safe_strerror (errno));
266 exit (1);
267 }
268 }
269
270 if ( cap_clear (zprivs_state.caps) )
271 {
272 fprintf (stderr, "privs_init: failed to cap_clear, %s\n",
273 safe_strerror (errno));
274 exit (1);
275 }
276
277 /* set permitted caps */
278 cap_set_flag(zprivs_state.caps, CAP_PERMITTED,
279 zprivs_state.syscaps_p->num,
280 zprivs_state.syscaps_p->caps,
281 CAP_SET);
282
283 /* set inheritable caps, if any */
284 if (zprivs_state.syscaps_i && zprivs_state.syscaps_i->num)
285 {
286 cap_set_flag(zprivs_state.caps, CAP_INHERITABLE,
287 zprivs_state.syscaps_i->num,
288 zprivs_state.syscaps_i->caps,
289 CAP_SET);
290 }
291
292 /* apply caps. CAP_EFFECTIVE is cleared. we'll raise the caps as
293 * and when, and only when, they are needed.
294 */
295 if ( cap_set_proc (zprivs_state.caps) )
296 {
297 fprintf (stderr, "privs_init: initial cap_set_proc failed\n");
298 exit (1);
299 }
300
301 /* set methods for the caller to use */
302 zprivs->change = zprivs_change_caps;
303 zprivs->current_state = zprivs_state_caps;
304}
305
306static void
307zprivs_caps_terminate (void)
308{
309 /* clear all capabilities */
310 if (zprivs_state.caps)
311 cap_clear (zprivs_state.caps);
312
313 /* and boom, capabilities are gone forever */
314 if ( cap_set_proc (zprivs_state.caps) )
315 {
316 fprintf (stderr, "privs_terminate: cap_set_proc failed, %s",
317 safe_strerror (errno) );
318 exit (1);
319 }
320
321 /* free up private state */
322 if (zprivs_state.syscaps_p->num)
323 {
324 XFREE (MTYPE_PRIVS, zprivs_state.syscaps_p->caps);
325 XFREE (MTYPE_PRIVS, zprivs_state.syscaps_p);
326 }
327
328 if (zprivs_state.syscaps_i && zprivs_state.syscaps_i->num)
329 {
330 XFREE (MTYPE_PRIVS, zprivs_state.syscaps_i->caps);
331 XFREE (MTYPE_PRIVS, zprivs_state.syscaps_i);
332 }
333
334 cap_free (zprivs_state.caps);
335}
336#elif defined (HAVE_SOLARIS_CAPABILITIES) /* !HAVE_LCAPS */
337
338/* Solaris specific capability/privilege methods
339 *
340 * Resources:
341 * - the 'privileges' man page
342 * - http://cvs.opensolaris.org
343 * - http://blogs.sun.com/roller/page/gbrunett?entry=privilege_enabling_set_id_programs1
344 */
345
346/* convert zebras privileges to system capabilities */
347static pset_t *
348zcaps2sys (zebra_capabilities_t *zcaps, int num)
349{
350 pset_t *syscaps;
351 int i, j = 0, count = 0;
352
353 if ((syscaps = priv_allocset()) == NULL)
354 {
355 fprintf (stderr, "%s: could not allocate syscaps!\n", __func__);
356 exit (1);
357 }
358
359 priv_emptyset (syscaps);
360
361 for (i=0; i < num; i++)
362 for (j = 0; j < cap_map[zcaps[i]].num; j++)
363 priv_addset (syscaps, cap_map[zcaps[i]].system_caps[j]);
364
365 return syscaps;
366}
367
368/* callback exported to users to RAISE and LOWER effective privileges
369 * from nothing to the given permitted set and back down
370 */
371int
372zprivs_change_caps (zebra_privs_ops_t op)
373{
374
375 /* should be no possibility of being called without valid caps */
376 assert (zprivs_state.syscaps_p);
377 if (!zprivs_state.syscaps_p)
378 {
379 fprintf (stderr, "%s: Eek, missing caps!", __func__);
380 exit (1);
381 }
382
383 /* to raise: copy original permitted into our working effective set
384 * to lower: just clear the working effective set
385 */
386 if (op == ZPRIVS_RAISE)
387 priv_copyset (zprivs_state.syscaps_p, zprivs_state.caps);
388 else if (op == ZPRIVS_LOWER)
389 priv_emptyset (zprivs_state.caps);
390 else
391 return -1;
392
393 if (setppriv (PRIV_SET, PRIV_EFFECTIVE, zprivs_state.caps) != 0)
394 return -1;
395
396 return 0;
397}
398
399/* Retrieve current privilege state, is it RAISED or LOWERED? */
400zebra_privs_current_t
401zprivs_state_caps (void)
402{
403 zebra_privs_current_t result;
404 pset_t *effective;
405
406 if ( (effective = priv_allocset()) == NULL)
407 {
408 fprintf (stderr, "%s: failed to get priv_allocset!\n", __func__,
409 safe_strerror (errno));
410 return ZPRIVS_UNKNOWN;
411 }
412
413 if (getppriv (PRIV_EFFECTIVE, effective))
414 {
415 fprintf (stderr, "%s: failed to get state!%s\n", __func__,
416 safe_strerror (errno));
417 result = ZPRIVS_UNKNOWN;
418 }
419 else
420 {
421 if (priv_isemptyset (effective) == B_TRUE)
422 result = ZPRIVS_LOWERED;
423 else
424 result = ZPRIVS_RAISED;
425 }
426
427 if (effective)
428 priv_freeset (effective);
429
430 return result;
431}
432
433static void
434zprivs_caps_init (struct zebra_privs_t *zprivs)
435{
436 pset_t *basic;
437 pset_t *empty;
438
439 /* the specified sets */
440 zprivs_state.syscaps_p = zcaps2sys (zprivs->caps_p, zprivs->cap_num_p);
441 zprivs_state.syscaps_i = zcaps2sys (zprivs->caps_i, zprivs->cap_num_i);
442
443 /* nonsensical to have gotten here but not have capabilities */
444 if (!zprivs_state.syscaps_p)
445 {
446 fprintf (stderr, "%s: capabilities enabled, "
447 "but no valid capabilities supplied\n",
448 __func__);
449 }
450
451 /* We retain the basic set in our permitted set, as Linux has no
452 * equivalent. The basic set on Linux hence is implicit, always
453 * there.
454 */
455 if ((basic = priv_str_to_set("basic", ",", NULL)) == NULL)
456 {
457 fprintf (stderr, "%s: couldn't get basic set!\n", __func__);
458 exit (1);
459 }
460
461 /* Add the basic set to the permitted set */
462 priv_union (basic, zprivs_state.syscaps_p);
463 priv_freeset (basic);
464
465 /* we need an empty set for 'effective', potentially for inheritable too */
466 if ( (empty = priv_allocset()) == NULL)
467 {
468 fprintf (stderr, "%s: couldn't get empty set!\n", __func__);
469 exit (1);
470 }
471 priv_emptyset (empty);
472
473 /* Hey kernel, we know about privileges!
474 * this isn't strictly required, use of setppriv should have same effect
475 */
476 if (setpflags (PRIV_AWARE, 1))
477 {
478 fprintf (stderr, "%s: error setting PRIV_AWARE!, %s\n", __func__,
479 safe_strerror (errno) );
480 exit (1);
481 }
482
483 /* need either valid or empty sets for both p and i.. */
484 assert (zprivs_state.syscaps_i && zprivs_state.syscaps_p);
485
486 /* set the permitted set */
487 if (setppriv (PRIV_SET, PRIV_PERMITTED, zprivs_state.syscaps_p))
488 {
489 fprintf (stderr, "%s: error setting permitted set!, %s\n", __func__,
490 safe_strerror (errno) );
491 exit (1);
492 }
493
494 /* set the inheritable set */
495 if (setppriv (PRIV_SET, PRIV_INHERITABLE, zprivs_state.syscaps_i))
496 {
497 fprintf (stderr, "%s: error setting inheritable set!, %s\n", __func__,
498 safe_strerror (errno) );
499 exit (1);
500 }
501
502 /* we have caps, we have no need to ever change back the original user */
503 if (zprivs_state.zuid)
504 {
505 if ( setreuid (zprivs_state.zuid, zprivs_state.zuid) )
506 {
507 fprintf (stderr, "%s: could not setreuid, %s\n",
508 __func__, safe_strerror (errno));
509 exit (1);
510 }
511 }
512
513 /* now clear the effective set and we're ready to go */
514 if (setppriv (PRIV_SET, PRIV_EFFECTIVE, empty))
515 {
516 fprintf (stderr, "%s: error setting effective set!, %s\n", __func__,
517 safe_strerror (errno) );
518 exit (1);
519 }
520
521 /* we'll use this as our working-storage privset */
522 zprivs_state.caps = empty;
523
524 /* set methods for the caller to use */
525 zprivs->change = zprivs_change_caps;
526 zprivs->current_state = zprivs_state_caps;
527}
528
529static void
530zprivs_caps_terminate (void)
531{
532 assert (zprivs_state.caps);
533
534 /* clear all capabilities */
535 priv_emptyset (zprivs_state.caps);
536 setppriv (PRIV_SET, PRIV_EFFECTIVE, zprivs_state.caps);
537 setppriv (PRIV_SET, PRIV_PERMITTED, zprivs_state.caps);
538 setppriv (PRIV_SET, PRIV_INHERITABLE, zprivs_state.caps);
539
540 /* free up private state */
541 if (zprivs_state.syscaps_p)
542 priv_freeset (zprivs_state.syscaps_p);
543 if (zprivs_state.syscaps_i)
544 priv_freeset (zprivs_state.syscaps_i);
545
546 priv_freeset (zprivs_state.caps);
547}
548#else /* !HAVE_LCAPS && ! HAVE_SOLARIS_CAPABILITIES */
549#error "Neither Solaris nor Linux capabilities, dazed and confused..."
550#endif /* HAVE_LCAPS */
551#endif /* HAVE_CAPABILITIES */
552
paul01245822003-05-20 01:22:17 +0000553int
554zprivs_change_uid (zebra_privs_ops_t op)
555{
paul28efaa32003-05-20 03:49:43 +0000556
paul01245822003-05-20 01:22:17 +0000557 if (op == ZPRIVS_RAISE)
558 return seteuid (zprivs_state.zsuid);
559 else if (op == ZPRIVS_LOWER)
560 return seteuid (zprivs_state.zuid);
561 else
562 return -1;
563}
564
565zebra_privs_current_t
566zprivs_state_uid (void)
567{
568 return ( (zprivs_state.zuid == geteuid()) ? ZPRIVS_LOWERED : ZPRIVS_RAISED);
569}
570
571int
572zprivs_change_null (zebra_privs_ops_t op)
573{
574 return 0;
575}
576
577zebra_privs_current_t
578zprivs_state_null (void)
579{
paulceacedb2005-09-29 14:39:32 +0000580 return zprivs_null_state;
paul01245822003-05-20 01:22:17 +0000581}
582
paul01245822003-05-20 01:22:17 +0000583void
584zprivs_init(struct zebra_privs_t *zprivs)
585{
586 struct passwd *pwentry = NULL;
587 struct group *grentry = NULL;
588
hassoba3a0bc2003-06-04 17:41:54 +0000589 if (!zprivs)
590 {
paul58a9d812003-06-11 05:12:40 +0000591 fprintf (stderr, "zprivs_init: called with NULL arg!\n");
hassoba3a0bc2003-06-04 17:41:54 +0000592 exit (1);
593 }
594
paul01245822003-05-20 01:22:17 +0000595 /* NULL privs */
596 if (! (zprivs->user || zprivs->group
597 || zprivs->cap_num_p || zprivs->cap_num_i) )
598 {
599 zprivs->change = zprivs_change_null;
600 zprivs->current_state = zprivs_state_null;
601 return;
602 }
603
604 if (zprivs->user)
605 {
606 if ( (pwentry = getpwnam (zprivs->user)) )
hassoba3a0bc2003-06-04 17:41:54 +0000607 {
608 zprivs_state.zuid = pwentry->pw_uid;
609 }
610 else
611 {
paul58a9d812003-06-11 05:12:40 +0000612 /* cant use log.h here as it depends on vty */
613 fprintf (stderr, "privs_init: could not lookup user %s\n",
614 zprivs->user);
hassoba3a0bc2003-06-04 17:41:54 +0000615 exit (1);
616 }
617 }
618
619 grentry = NULL;
620
621 if (zprivs->vty_group)
622 /* Add the vty_group to the supplementary groups so it can be chowned to */
623 {
624 if ( (grentry = getgrnam (zprivs->vty_group)) )
625 {
626 zprivs_state.vtygrp = grentry->gr_gid;
627 if ( setgroups (1, &zprivs_state.vtygrp) )
628 {
paul58a9d812003-06-11 05:12:40 +0000629 fprintf (stderr, "privs_init: could not setgroups, %s\n",
ajs6099b3b2004-11-20 02:06:59 +0000630 safe_strerror (errno) );
hassoba3a0bc2003-06-04 17:41:54 +0000631 exit (1);
632 }
633 }
paul01245822003-05-20 01:22:17 +0000634 else
635 {
paul58a9d812003-06-11 05:12:40 +0000636 fprintf (stderr, "privs_init: could not lookup vty group %s\n",
637 zprivs->vty_group);
paul01245822003-05-20 01:22:17 +0000638 exit (1);
639 }
640 }
641
642 if (zprivs->group)
643 {
hassoba3a0bc2003-06-04 17:41:54 +0000644 if ( (grentry = getgrnam (zprivs->group)) )
645 {
646 zprivs_state.zgid = grentry->gr_gid;
647 }
paul01245822003-05-20 01:22:17 +0000648 else
649 {
paul58a9d812003-06-11 05:12:40 +0000650 fprintf (stderr, "privs_init: could not lookup group %s\n",
651 zprivs->group);
paul01245822003-05-20 01:22:17 +0000652 exit (1);
653 }
paul01245822003-05-20 01:22:17 +0000654 /* change group now, forever. uid we do later */
655 if ( setregid (zprivs_state.zgid, zprivs_state.zgid) )
656 {
paul58a9d812003-06-11 05:12:40 +0000657 fprintf (stderr, "zprivs_init: could not setregid, %s\n",
ajs6099b3b2004-11-20 02:06:59 +0000658 safe_strerror (errno) );
paul01245822003-05-20 01:22:17 +0000659 exit (1);
660 }
661 }
662
paulceacedb2005-09-29 14:39:32 +0000663#ifdef HAVE_CAPABILITIES
664 zprivs_caps_init (zprivs);
665#else /* !HAVE_CAPABILITIES */
paul01245822003-05-20 01:22:17 +0000666 /* we dont have caps. we'll need to maintain rid and saved uid
667 * and change euid back to saved uid (who we presume has all neccessary
668 * privileges) whenever we are asked to raise our privileges.
paulceacedb2005-09-29 14:39:32 +0000669 *
670 * This is not worth that much security wise, but all we can do.
paul01245822003-05-20 01:22:17 +0000671 */
672 zprivs_state.zsuid = geteuid();
673 if ( zprivs_state.zuid )
674 {
675 if ( setreuid (-1, zprivs_state.zuid) )
676 {
paul58a9d812003-06-11 05:12:40 +0000677 fprintf (stderr, "privs_init (uid): could not setreuid, %s\n",
ajs6099b3b2004-11-20 02:06:59 +0000678 safe_strerror (errno));
paul01245822003-05-20 01:22:17 +0000679 exit (1);
680 }
681 }
682
683 zprivs->change = zprivs_change_uid;
684 zprivs->current_state = zprivs_state_uid;
paulceacedb2005-09-29 14:39:32 +0000685#endif /* HAVE_CAPABILITIES */
paul01245822003-05-20 01:22:17 +0000686}
687
688void
paulceacedb2005-09-29 14:39:32 +0000689zprivs_terminate (struct zebra_privs_t *zprivs)
paul01245822003-05-20 01:22:17 +0000690{
paulceacedb2005-09-29 14:39:32 +0000691 if (!zprivs)
paul01245822003-05-20 01:22:17 +0000692 {
paulceacedb2005-09-29 14:39:32 +0000693 fprintf (stderr, "%s: no privs struct given, terminating", __func__);
694 exit (0);
695 }
paul01245822003-05-20 01:22:17 +0000696
paulceacedb2005-09-29 14:39:32 +0000697#ifdef HAVE_CAPABILITIES
698 zprivs_caps_terminate();
699#else /* !HAVE_CAPABILITIES */
paul01245822003-05-20 01:22:17 +0000700 if (zprivs_state.zuid)
701 {
702 if ( setreuid (zprivs_state.zuid, zprivs_state.zuid) )
703 {
paulceacedb2005-09-29 14:39:32 +0000704 fprintf (stderr, "privs_terminate: could not setreuid, %s",
ajs6099b3b2004-11-20 02:06:59 +0000705 safe_strerror (errno) );
paul01245822003-05-20 01:22:17 +0000706 exit (1);
707 }
708 }
709#endif /* HAVE_LCAPS */
paulceacedb2005-09-29 14:39:32 +0000710
711 zprivs->change = zprivs_change_null;
712 zprivs->current_state = zprivs_state_null;
713 zprivs_null_state = ZPRIVS_LOWERED;
paul01245822003-05-20 01:22:17 +0000714 return;
715}
hassoba3a0bc2003-06-04 17:41:54 +0000716
717void
718zprivs_get_ids(struct zprivs_ids_t *ids)
719{
720
721 ids->uid_priv = getuid();
722 (zprivs_state.zuid) ? (ids->uid_normal = zprivs_state.zuid)
723 : (ids->uid_normal = -1);
724 (zprivs_state.zgid) ? (ids->gid_normal = zprivs_state.zgid)
725 : (ids->gid_normal = -1);
726 (zprivs_state.vtygrp) ? (ids->gid_vty = zprivs_state.vtygrp)
727 : (ids->gid_vty = -1);
728
729 return;
730}