2 * Copyright (c) 1999-2002, 2007 Robert N. M. Watson
3 * Copyright (c) 2001-2005 Networks Associates Technology, Inc.
4 * Copyright (c) 2005 Tom Rhodes
7 * This software was developed by Robert Watson for the TrustedBSD Project.
8 * It was later enhanced by Tom Rhodes for the TrustedBSD Project.
10 * This software was developed for the FreeBSD Project in part by Network
11 * Associates Laboratories, the Security Research Division of Network
12 * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"),
13 * as part of the DARPA CHATS research program.
15 * Redistribution and use in source and binary forms, with or without
16 * modification, are permitted provided that the following conditions
18 * 1. Redistributions of source code must retain the above copyright
19 * notice, this list of conditions and the following disclaimer.
20 * 2. Redistributions in binary form must reproduce the above copyright
21 * notice, this list of conditions and the following disclaimer in the
22 * documentation and/or other materials provided with the distribution.
24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
40 * Developed by the TrustedBSD Project.
42 * "BSD Extended" MAC policy, allowing the administrator to impose mandatory
43 * firewall-like rules regarding users and file system objects.
46 #include <sys/param.h>
48 #include <sys/kernel.h>
51 #include <sys/malloc.h>
52 #include <sys/module.h>
53 #include <sys/mount.h>
54 #include <sys/mutex.h>
57 #include <sys/systm.h>
58 #include <sys/vnode.h>
59 #include <sys/sysctl.h>
60 #include <sys/syslog.h>
62 #include <security/mac/mac_policy.h>
63 #include <security/mac_bsdextended/mac_bsdextended.h>
65 static struct mtx ugidfw_mtx;
67 SYSCTL_DECL(_security_mac);
69 SYSCTL_NODE(_security_mac, OID_AUTO, bsdextended, CTLFLAG_RW, 0,
70 "TrustedBSD extended BSD MAC policy controls");
72 static int ugidfw_enabled = 1;
73 SYSCTL_INT(_security_mac_bsdextended, OID_AUTO, enabled, CTLFLAG_RW,
74 &ugidfw_enabled, 0, "Enforce extended BSD policy");
75 TUNABLE_INT("security.mac.bsdextended.enabled", &ugidfw_enabled);
77 MALLOC_DEFINE(M_MACBSDEXTENDED, "mac_bsdextended", "BSD Extended MAC rule");
79 #define MAC_BSDEXTENDED_MAXRULES 250
80 static struct mac_bsdextended_rule *rules[MAC_BSDEXTENDED_MAXRULES];
81 static int rule_count = 0;
82 static int rule_slots = 0;
83 static int rule_version = MB_VERSION;
85 SYSCTL_INT(_security_mac_bsdextended, OID_AUTO, rule_count, CTLFLAG_RD,
86 &rule_count, 0, "Number of defined rules\n");
87 SYSCTL_INT(_security_mac_bsdextended, OID_AUTO, rule_slots, CTLFLAG_RD,
88 &rule_slots, 0, "Number of used rule slots\n");
89 SYSCTL_INT(_security_mac_bsdextended, OID_AUTO, rule_version, CTLFLAG_RD,
90 &rule_version, 0, "Version number for API\n");
93 * This is just used for logging purposes, eventually we would like to log
94 * much more then failed requests.
96 static int ugidfw_logging;
97 SYSCTL_INT(_security_mac_bsdextended, OID_AUTO, logging, CTLFLAG_RW,
98 &ugidfw_logging, 0, "Log failed authorization requests");
101 * This tunable is here for compatibility. It will allow the user to switch
102 * between the new mode (first rule matches) and the old functionality (all
105 static int ugidfw_firstmatch_enabled;
106 SYSCTL_INT(_security_mac_bsdextended, OID_AUTO, firstmatch_enabled,
107 CTLFLAG_RW, &ugidfw_firstmatch_enabled, 1,
108 "Disable/enable match first rule functionality");
111 ugidfw_rule_valid(struct mac_bsdextended_rule *rule)
114 if ((rule->mbr_subject.mbs_flags | MBS_ALL_FLAGS) != MBS_ALL_FLAGS)
116 if ((rule->mbr_subject.mbs_neg | MBS_ALL_FLAGS) != MBS_ALL_FLAGS)
118 if ((rule->mbr_object.mbo_flags | MBO_ALL_FLAGS) != MBO_ALL_FLAGS)
120 if ((rule->mbr_object.mbo_neg | MBO_ALL_FLAGS) != MBO_ALL_FLAGS)
122 if ((rule->mbr_object.mbo_neg | MBO_TYPE_DEFINED) &&
123 (rule->mbr_object.mbo_type | MBO_ALL_TYPE) != MBO_ALL_TYPE)
125 if ((rule->mbr_mode | MBI_ALLPERM) != MBI_ALLPERM)
131 sysctl_rule(SYSCTL_HANDLER_ARGS)
133 struct mac_bsdextended_rule temprule, *ruleptr;
135 int error, index, *name;
143 if (index >= MAC_BSDEXTENDED_MAXRULES)
147 if (req->newptr && req->newlen != 0) {
148 error = SYSCTL_IN(req, &temprule, sizeof(temprule));
151 MALLOC(ruleptr, struct mac_bsdextended_rule *,
152 sizeof(*ruleptr), M_MACBSDEXTENDED, M_WAITOK | M_ZERO);
155 mtx_lock(&ugidfw_mtx);
157 if (index < 0 || index > rule_slots + 1) {
161 if (rules[index] == NULL) {
165 temprule = *rules[index];
167 if (req->newptr && req->newlen == 0) {
168 KASSERT(ruleptr == NULL, ("sysctl_rule: ruleptr != NULL"));
169 ruleptr = rules[index];
170 if (ruleptr == NULL) {
176 } else if (req->newptr) {
177 error = ugidfw_rule_valid(&temprule);
180 if (rules[index] == NULL) {
182 rules[index] = ruleptr;
184 if (index + 1 > rule_slots)
185 rule_slots = index + 1;
188 *rules[index] = temprule;
191 mtx_unlock(&ugidfw_mtx);
193 FREE(ruleptr, M_MACBSDEXTENDED);
194 if (req->oldptr && error == 0)
195 error = SYSCTL_OUT(req, &temprule, sizeof(temprule));
199 SYSCTL_NODE(_security_mac_bsdextended, OID_AUTO, rules,
200 CTLFLAG_MPSAFE | CTLFLAG_RW, sysctl_rule, "BSD extended MAC rules");
203 ugidfw_init(struct mac_policy_conf *mpc)
206 mtx_init(&ugidfw_mtx, "mac_bsdextended lock", NULL, MTX_DEF);
210 ugidfw_destroy(struct mac_policy_conf *mpc)
214 for (i = 0; i < MAC_BSDEXTENDED_MAXRULES; i++) {
215 if (rules[i] != NULL)
216 free(rules[i], M_MACBSDEXTENDED);
218 mtx_destroy(&ugidfw_mtx);
222 ugidfw_rulecheck(struct mac_bsdextended_rule *rule,
223 struct ucred *cred, struct vnode *vp, struct vattr *vap, int acc_mode)
229 * Is there a subject match?
231 mtx_assert(&ugidfw_mtx, MA_OWNED);
232 if (rule->mbr_subject.mbs_flags & MBS_UID_DEFINED) {
233 match = ((cred->cr_uid <= rule->mbr_subject.mbs_uid_max &&
234 cred->cr_uid >= rule->mbr_subject.mbs_uid_min) ||
235 (cred->cr_ruid <= rule->mbr_subject.mbs_uid_max &&
236 cred->cr_ruid >= rule->mbr_subject.mbs_uid_min) ||
237 (cred->cr_svuid <= rule->mbr_subject.mbs_uid_max &&
238 cred->cr_svuid >= rule->mbr_subject.mbs_uid_min));
239 if (rule->mbr_subject.mbs_neg & MBS_UID_DEFINED)
245 if (rule->mbr_subject.mbs_flags & MBS_GID_DEFINED) {
246 match = ((cred->cr_rgid <= rule->mbr_subject.mbs_gid_max &&
247 cred->cr_rgid >= rule->mbr_subject.mbs_gid_min) ||
248 (cred->cr_svgid <= rule->mbr_subject.mbs_gid_max &&
249 cred->cr_svgid >= rule->mbr_subject.mbs_gid_min));
251 for (i = 0; i < cred->cr_ngroups; i++) {
252 if (cred->cr_groups[i]
253 <= rule->mbr_subject.mbs_gid_max &&
255 >= rule->mbr_subject.mbs_gid_min) {
261 if (rule->mbr_subject.mbs_neg & MBS_GID_DEFINED)
267 if (rule->mbr_subject.mbs_flags & MBS_PRISON_DEFINED) {
268 match = (cred->cr_prison != NULL &&
269 cred->cr_prison->pr_id == rule->mbr_subject.mbs_prison);
270 if (rule->mbr_subject.mbs_neg & MBS_PRISON_DEFINED)
277 * Is there an object match?
279 if (rule->mbr_object.mbo_flags & MBO_UID_DEFINED) {
280 match = (vap->va_uid <= rule->mbr_object.mbo_uid_max &&
281 vap->va_uid >= rule->mbr_object.mbo_uid_min);
282 if (rule->mbr_object.mbo_neg & MBO_UID_DEFINED)
288 if (rule->mbr_object.mbo_flags & MBO_GID_DEFINED) {
289 match = (vap->va_gid <= rule->mbr_object.mbo_gid_max &&
290 vap->va_gid >= rule->mbr_object.mbo_gid_min);
291 if (rule->mbr_object.mbo_neg & MBO_GID_DEFINED)
297 if (rule->mbr_object.mbo_flags & MBO_FSID_DEFINED) {
298 match = (bcmp(&(vp->v_mount->mnt_stat.f_fsid),
299 &(rule->mbr_object.mbo_fsid),
300 sizeof(rule->mbr_object.mbo_fsid)) == 0);
301 if (rule->mbr_object.mbo_neg & MBO_FSID_DEFINED)
307 if (rule->mbr_object.mbo_flags & MBO_SUID) {
308 match = (vap->va_mode & VSUID);
309 if (rule->mbr_object.mbo_neg & MBO_SUID)
315 if (rule->mbr_object.mbo_flags & MBO_SGID) {
316 match = (vap->va_mode & VSGID);
317 if (rule->mbr_object.mbo_neg & MBO_SGID)
323 if (rule->mbr_object.mbo_flags & MBO_UID_SUBJECT) {
324 match = (vap->va_uid == cred->cr_uid ||
325 vap->va_uid == cred->cr_ruid ||
326 vap->va_uid == cred->cr_svuid);
327 if (rule->mbr_object.mbo_neg & MBO_UID_SUBJECT)
333 if (rule->mbr_object.mbo_flags & MBO_GID_SUBJECT) {
334 match = (groupmember(vap->va_gid, cred) ||
335 vap->va_gid == cred->cr_rgid ||
336 vap->va_gid == cred->cr_svgid);
337 if (rule->mbr_object.mbo_neg & MBO_GID_SUBJECT)
343 if (rule->mbr_object.mbo_flags & MBO_TYPE_DEFINED) {
344 switch (vap->va_type) {
346 match = (rule->mbr_object.mbo_type & MBO_TYPE_REG);
349 match = (rule->mbr_object.mbo_type & MBO_TYPE_DIR);
352 match = (rule->mbr_object.mbo_type & MBO_TYPE_BLK);
355 match = (rule->mbr_object.mbo_type & MBO_TYPE_CHR);
358 match = (rule->mbr_object.mbo_type & MBO_TYPE_LNK);
361 match = (rule->mbr_object.mbo_type & MBO_TYPE_SOCK);
364 match = (rule->mbr_object.mbo_type & MBO_TYPE_FIFO);
369 if (rule->mbr_object.mbo_neg & MBO_TYPE_DEFINED)
376 * Is the access permitted?
378 if ((rule->mbr_mode & acc_mode) != acc_mode) {
380 log(LOG_AUTHPRIV, "mac_bsdextended: %d:%d request %d"
381 " on %d:%d failed. \n", cred->cr_ruid,
382 cred->cr_rgid, acc_mode, vap->va_uid,
388 * If the rule matched, permits access, and first match is enabled,
391 if (ugidfw_firstmatch_enabled)
392 return (EJUSTRETURN);
398 ugidfw_check(struct ucred *cred, struct vnode *vp, struct vattr *vap,
404 * XXXRW: More specific privilege selection needed.
406 if (suser_cred(cred, 0) == 0)
410 * Since we do not separately handle append, map append to write.
412 if (acc_mode & MBI_APPEND) {
413 acc_mode &= ~MBI_APPEND;
414 acc_mode |= MBI_WRITE;
416 mtx_lock(&ugidfw_mtx);
417 for (i = 0; i < rule_slots; i++) {
418 if (rules[i] == NULL)
420 error = ugidfw_rulecheck(rules[i], cred,
422 if (error == EJUSTRETURN)
425 mtx_unlock(&ugidfw_mtx);
429 mtx_unlock(&ugidfw_mtx);
434 ugidfw_check_vp(struct ucred *cred, struct vnode *vp, int acc_mode)
441 error = VOP_GETATTR(vp, &vap, cred, curthread);
444 return (ugidfw_check(cred, vp, &vap, acc_mode));
448 ugidfw_check_system_acct(struct ucred *cred, struct vnode *vp,
449 struct label *vplabel)
453 return (ugidfw_check_vp(cred, vp, MBI_WRITE));
459 ugidfw_check_system_auditctl(struct ucred *cred, struct vnode *vp,
460 struct label *vplabel)
464 return (ugidfw_check_vp(cred, vp, MBI_WRITE));
470 ugidfw_check_system_swapon(struct ucred *cred, struct vnode *vp,
471 struct label *vplabel)
474 return (ugidfw_check_vp(cred, vp, MBI_WRITE));
478 ugidfw_check_vnode_access(struct ucred *cred, struct vnode *vp,
479 struct label *vplabel, int acc_mode)
482 return (ugidfw_check_vp(cred, vp, acc_mode));
486 ugidfw_check_vnode_chdir(struct ucred *cred, struct vnode *dvp,
487 struct label *dvplabel)
490 return (ugidfw_check_vp(cred, dvp, MBI_EXEC));
494 ugidfw_check_vnode_chroot(struct ucred *cred, struct vnode *dvp,
495 struct label *dvplabel)
498 return (ugidfw_check_vp(cred, dvp, MBI_EXEC));
502 ugidfw_check_create_vnode(struct ucred *cred, struct vnode *dvp,
503 struct label *dvplabel, struct componentname *cnp, struct vattr *vap)
506 return (ugidfw_check_vp(cred, dvp, MBI_WRITE));
510 ugidfw_check_vnode_deleteacl(struct ucred *cred, struct vnode *vp,
511 struct label *vplabel, acl_type_t type)
514 return (ugidfw_check_vp(cred, vp, MBI_ADMIN));
518 ugidfw_check_vnode_deleteextattr(struct ucred *cred,
519 struct vnode *vp, struct label *vplabel, int attrnamespace,
523 return (ugidfw_check_vp(cred, vp, MBI_WRITE));
527 ugidfw_check_vnode_exec(struct ucred *cred, struct vnode *vp,
528 struct label *vplabel, struct image_params *imgp,
529 struct label *execlabel)
532 return (ugidfw_check_vp(cred, vp, MBI_READ|MBI_EXEC));
536 ugidfw_check_vnode_getacl(struct ucred *cred, struct vnode *vp,
537 struct label *vplabel, acl_type_t type)
540 return (ugidfw_check_vp(cred, vp, MBI_STAT));
544 ugidfw_check_vnode_getextattr(struct ucred *cred, struct vnode *vp,
545 struct label *vplabel, int attrnamespace, const char *name,
549 return (ugidfw_check_vp(cred, vp, MBI_READ));
553 ugidfw_check_vnode_link(struct ucred *cred, struct vnode *dvp,
554 struct label *dvplabel, struct vnode *vp, struct label *label,
555 struct componentname *cnp)
559 error = ugidfw_check_vp(cred, dvp, MBI_WRITE);
562 error = ugidfw_check_vp(cred, vp, MBI_WRITE);
569 ugidfw_check_vnode_listextattr(struct ucred *cred, struct vnode *vp,
570 struct label *vplabel, int attrnamespace)
573 return (ugidfw_check_vp(cred, vp, MBI_READ));
577 ugidfw_check_vnode_lookup(struct ucred *cred, struct vnode *dvp,
578 struct label *dvplabel, struct componentname *cnp)
581 return (ugidfw_check_vp(cred, dvp, MBI_EXEC));
585 ugidfw_check_vnode_open(struct ucred *cred, struct vnode *vp,
586 struct label *vplabel, int acc_mode)
589 return (ugidfw_check_vp(cred, vp, acc_mode));
593 ugidfw_check_vnode_readdir(struct ucred *cred, struct vnode *dvp,
594 struct label *dvplabel)
597 return (ugidfw_check_vp(cred, dvp, MBI_READ));
601 ugidfw_check_vnode_readdlink(struct ucred *cred, struct vnode *vp,
602 struct label *vplabel)
605 return (ugidfw_check_vp(cred, vp, MBI_READ));
609 ugidfw_check_vnode_rename_from(struct ucred *cred, struct vnode *dvp,
610 struct label *dvplabel, struct vnode *vp, struct label *vplabel,
611 struct componentname *cnp)
615 error = ugidfw_check_vp(cred, dvp, MBI_WRITE);
618 return (ugidfw_check_vp(cred, vp, MBI_WRITE));
622 ugidfw_check_vnode_rename_to(struct ucred *cred, struct vnode *dvp,
623 struct label *dvplabel, struct vnode *vp, struct label *vplabel,
624 int samedir, struct componentname *cnp)
628 error = ugidfw_check_vp(cred, dvp, MBI_WRITE);
632 error = ugidfw_check_vp(cred, vp, MBI_WRITE);
637 ugidfw_check_vnode_revoke(struct ucred *cred, struct vnode *vp,
638 struct label *vplabel)
641 return (ugidfw_check_vp(cred, vp, MBI_ADMIN));
645 ugidfw_check_setacl_vnode(struct ucred *cred, struct vnode *vp,
646 struct label *vplabel, acl_type_t type, struct acl *acl)
649 return (ugidfw_check_vp(cred, vp, MBI_ADMIN));
653 ugidfw_check_vnode_setextattr(struct ucred *cred, struct vnode *vp,
654 struct label *vplabel, int attrnamespace, const char *name,
658 return (ugidfw_check_vp(cred, vp, MBI_WRITE));
662 ugidfw_check_vnode_setflags(struct ucred *cred, struct vnode *vp,
663 struct label *vplabel, u_long flags)
666 return (ugidfw_check_vp(cred, vp, MBI_ADMIN));
670 ugidfw_check_vnode_setmode(struct ucred *cred, struct vnode *vp,
671 struct label *vplabel, mode_t mode)
674 return (ugidfw_check_vp(cred, vp, MBI_ADMIN));
678 ugidfw_check_vnode_setowner(struct ucred *cred, struct vnode *vp,
679 struct label *vplabel, uid_t uid, gid_t gid)
682 return (ugidfw_check_vp(cred, vp, MBI_ADMIN));
686 ugidfw_check_vnode_setutimes(struct ucred *cred, struct vnode *vp,
687 struct label *vplabel, struct timespec atime, struct timespec utime)
690 return (ugidfw_check_vp(cred, vp, MBI_ADMIN));
694 ugidfw_check_vnode_stat(struct ucred *active_cred,
695 struct ucred *file_cred, struct vnode *vp, struct label *vplabel)
698 return (ugidfw_check_vp(active_cred, vp, MBI_STAT));
702 ugidfw_check_vnode_unlink(struct ucred *cred, struct vnode *dvp,
703 struct label *dvplabel, struct vnode *vp, struct label *vplabel,
704 struct componentname *cnp)
708 error = ugidfw_check_vp(cred, dvp, MBI_WRITE);
711 return (ugidfw_check_vp(cred, vp, MBI_WRITE));
714 static struct mac_policy_ops ugidfw_ops =
716 .mpo_destroy = ugidfw_destroy,
717 .mpo_init = ugidfw_init,
718 .mpo_check_system_acct = ugidfw_check_system_acct,
719 .mpo_check_system_auditctl = ugidfw_check_system_auditctl,
720 .mpo_check_system_swapon = ugidfw_check_system_swapon,
721 .mpo_check_vnode_access = ugidfw_check_vnode_access,
722 .mpo_check_vnode_chdir = ugidfw_check_vnode_chdir,
723 .mpo_check_vnode_chroot = ugidfw_check_vnode_chroot,
724 .mpo_check_vnode_create = ugidfw_check_create_vnode,
725 .mpo_check_vnode_deleteacl = ugidfw_check_vnode_deleteacl,
726 .mpo_check_vnode_deleteextattr = ugidfw_check_vnode_deleteextattr,
727 .mpo_check_vnode_exec = ugidfw_check_vnode_exec,
728 .mpo_check_vnode_getacl = ugidfw_check_vnode_getacl,
729 .mpo_check_vnode_getextattr = ugidfw_check_vnode_getextattr,
730 .mpo_check_vnode_link = ugidfw_check_vnode_link,
731 .mpo_check_vnode_listextattr = ugidfw_check_vnode_listextattr,
732 .mpo_check_vnode_lookup = ugidfw_check_vnode_lookup,
733 .mpo_check_vnode_open = ugidfw_check_vnode_open,
734 .mpo_check_vnode_readdir = ugidfw_check_vnode_readdir,
735 .mpo_check_vnode_readlink = ugidfw_check_vnode_readdlink,
736 .mpo_check_vnode_rename_from = ugidfw_check_vnode_rename_from,
737 .mpo_check_vnode_rename_to = ugidfw_check_vnode_rename_to,
738 .mpo_check_vnode_revoke = ugidfw_check_vnode_revoke,
739 .mpo_check_vnode_setacl = ugidfw_check_setacl_vnode,
740 .mpo_check_vnode_setextattr = ugidfw_check_vnode_setextattr,
741 .mpo_check_vnode_setflags = ugidfw_check_vnode_setflags,
742 .mpo_check_vnode_setmode = ugidfw_check_vnode_setmode,
743 .mpo_check_vnode_setowner = ugidfw_check_vnode_setowner,
744 .mpo_check_vnode_setutimes = ugidfw_check_vnode_setutimes,
745 .mpo_check_vnode_stat = ugidfw_check_vnode_stat,
746 .mpo_check_vnode_unlink = ugidfw_check_vnode_unlink,
749 MAC_POLICY_SET(&ugidfw_ops, mac_bsdextended, "TrustedBSD MAC/BSD Extended",
750 MPC_LOADTIME_FLAG_UNLOADOK, NULL);