2 * Implementation of the security services.
4 * Authors : Stephen Smalley, <sds@epoch.ncsc.mil>
5 * James Morris <jmorris@redhat.com>
7 * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
9 * Support for enhanced MLS infrastructure.
10 * Support for context based audit filters.
12 * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
14 * Added conditional policy language extensions
16 * Updated: Hewlett-Packard <paul.moore@hp.com>
18 * Added support for NetLabel
19 * Added support for the policy capability bitmap
21 * Updated: Chad Sellers <csellers@tresys.com>
23 * Added validation of kernel classes and permissions
25 * Updated: KaiGai Kohei <kaigai@ak.jp.nec.com>
27 * Added support for bounds domain and audit messaged on masked permissions
29 * Updated: Guido Trentalancia <guido@trentalancia.com>
31 * Added support for runtime switching of the policy type
33 * Copyright (C) 2008, 2009 NEC Corporation
34 * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
35 * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
36 * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC
37 * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
38 * This program is free software; you can redistribute it and/or modify
39 * it under the terms of the GNU General Public License as published by
40 * the Free Software Foundation, version 2.
42 #include <linux/kernel.h>
43 #include <linux/slab.h>
44 #include <linux/string.h>
45 #include <linux/spinlock.h>
46 #include <linux/rcupdate.h>
47 #include <linux/errno.h>
49 #include <linux/sched.h>
50 #include <linux/audit.h>
51 #include <linux/mutex.h>
52 #include <linux/selinux.h>
53 #include <linux/flex_array.h>
54 #include <linux/vmalloc.h>
55 #include <net/netlabel.h>
65 #include "conditional.h"
73 extern void selnl_notify_policyload(u32 seqno);
75 int selinux_policycap_netpeer;
76 int selinux_policycap_openperm;
78 static DEFINE_RWLOCK(policy_rwlock);
80 static struct sidtab sidtab;
81 struct policydb policydb;
85 * The largest sequence number that has been used when
86 * providing an access decision to the access vector cache.
87 * The sequence number only changes when a policy change
90 static u32 latest_granting;
92 /* Forward declaration. */
93 static int context_struct_to_string(struct context *context, char **scontext,
96 static void context_struct_compute_av(struct context *scontext,
97 struct context *tcontext,
99 struct av_decision *avd);
101 struct selinux_mapping {
102 u16 value; /* policy value */
104 u32 perms[sizeof(u32) * 8];
107 static struct selinux_mapping *current_mapping;
108 static u16 current_mapping_size;
110 static int selinux_set_mapping(struct policydb *pol,
111 struct security_class_mapping *map,
112 struct selinux_mapping **out_map_p,
115 struct selinux_mapping *out_map = NULL;
116 size_t size = sizeof(struct selinux_mapping);
119 bool print_unknown_handle = false;
121 /* Find number of classes in the input mapping */
128 /* Allocate space for the class records, plus one for class zero */
129 out_map = kcalloc(++i, size, GFP_ATOMIC);
133 /* Store the raw class and permission values */
135 while (map[j].name) {
136 struct security_class_mapping *p_in = map + (j++);
137 struct selinux_mapping *p_out = out_map + j;
139 /* An empty class string skips ahead */
140 if (!strcmp(p_in->name, "")) {
141 p_out->num_perms = 0;
145 p_out->value = string_to_security_class(pol, p_in->name);
148 "SELinux: Class %s not defined in policy.\n",
150 if (pol->reject_unknown)
152 p_out->num_perms = 0;
153 print_unknown_handle = true;
158 while (p_in->perms && p_in->perms[k]) {
159 /* An empty permission string skips ahead */
160 if (!*p_in->perms[k]) {
164 p_out->perms[k] = string_to_av_perm(pol, p_out->value,
166 if (!p_out->perms[k]) {
168 "SELinux: Permission %s in class %s not defined in policy.\n",
169 p_in->perms[k], p_in->name);
170 if (pol->reject_unknown)
172 print_unknown_handle = true;
177 p_out->num_perms = k;
180 if (print_unknown_handle)
181 printk(KERN_INFO "SELinux: the above unknown classes and permissions will be %s\n",
182 pol->allow_unknown ? "allowed" : "denied");
184 *out_map_p = out_map;
193 * Get real, policy values from mapped values
196 static u16 unmap_class(u16 tclass)
198 if (tclass < current_mapping_size)
199 return current_mapping[tclass].value;
205 * Get kernel value for class from its policy value
207 static u16 map_class(u16 pol_value)
211 for (i = 1; i < current_mapping_size; i++) {
212 if (current_mapping[i].value == pol_value)
219 static void map_decision(u16 tclass, struct av_decision *avd,
222 if (tclass < current_mapping_size) {
223 unsigned i, n = current_mapping[tclass].num_perms;
226 for (i = 0, result = 0; i < n; i++) {
227 if (avd->allowed & current_mapping[tclass].perms[i])
229 if (allow_unknown && !current_mapping[tclass].perms[i])
232 avd->allowed = result;
234 for (i = 0, result = 0; i < n; i++)
235 if (avd->auditallow & current_mapping[tclass].perms[i])
237 avd->auditallow = result;
239 for (i = 0, result = 0; i < n; i++) {
240 if (avd->auditdeny & current_mapping[tclass].perms[i])
242 if (!allow_unknown && !current_mapping[tclass].perms[i])
246 * In case the kernel has a bug and requests a permission
247 * between num_perms and the maximum permission number, we
248 * should audit that denial
250 for (; i < (sizeof(u32)*8); i++)
252 avd->auditdeny = result;
256 int security_mls_enabled(void)
258 return policydb.mls_enabled;
262 * Return the boolean value of a constraint expression
263 * when it is applied to the specified source and target
266 * xcontext is a special beast... It is used by the validatetrans rules
267 * only. For these rules, scontext is the context before the transition,
268 * tcontext is the context after the transition, and xcontext is the context
269 * of the process performing the transition. All other callers of
270 * constraint_expr_eval should pass in NULL for xcontext.
272 static int constraint_expr_eval(struct context *scontext,
273 struct context *tcontext,
274 struct context *xcontext,
275 struct constraint_expr *cexpr)
279 struct role_datum *r1, *r2;
280 struct mls_level *l1, *l2;
281 struct constraint_expr *e;
282 int s[CEXPR_MAXDEPTH];
285 for (e = cexpr; e; e = e->next) {
286 switch (e->expr_type) {
302 if (sp == (CEXPR_MAXDEPTH - 1))
306 val1 = scontext->user;
307 val2 = tcontext->user;
310 val1 = scontext->type;
311 val2 = tcontext->type;
314 val1 = scontext->role;
315 val2 = tcontext->role;
316 r1 = policydb.role_val_to_struct[val1 - 1];
317 r2 = policydb.role_val_to_struct[val2 - 1];
320 s[++sp] = ebitmap_get_bit(&r1->dominates,
324 s[++sp] = ebitmap_get_bit(&r2->dominates,
328 s[++sp] = (!ebitmap_get_bit(&r1->dominates,
330 !ebitmap_get_bit(&r2->dominates,
338 l1 = &(scontext->range.level[0]);
339 l2 = &(tcontext->range.level[0]);
342 l1 = &(scontext->range.level[0]);
343 l2 = &(tcontext->range.level[1]);
346 l1 = &(scontext->range.level[1]);
347 l2 = &(tcontext->range.level[0]);
350 l1 = &(scontext->range.level[1]);
351 l2 = &(tcontext->range.level[1]);
354 l1 = &(scontext->range.level[0]);
355 l2 = &(scontext->range.level[1]);
358 l1 = &(tcontext->range.level[0]);
359 l2 = &(tcontext->range.level[1]);
364 s[++sp] = mls_level_eq(l1, l2);
367 s[++sp] = !mls_level_eq(l1, l2);
370 s[++sp] = mls_level_dom(l1, l2);
373 s[++sp] = mls_level_dom(l2, l1);
376 s[++sp] = mls_level_incomp(l2, l1);
390 s[++sp] = (val1 == val2);
393 s[++sp] = (val1 != val2);
401 if (sp == (CEXPR_MAXDEPTH-1))
404 if (e->attr & CEXPR_TARGET)
406 else if (e->attr & CEXPR_XTARGET) {
413 if (e->attr & CEXPR_USER)
415 else if (e->attr & CEXPR_ROLE)
417 else if (e->attr & CEXPR_TYPE)
426 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
429 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
447 * security_dump_masked_av - dumps masked permissions during
448 * security_compute_av due to RBAC, MLS/Constraint and Type bounds.
450 static int dump_masked_av_helper(void *k, void *d, void *args)
452 struct perm_datum *pdatum = d;
453 char **permission_names = args;
455 BUG_ON(pdatum->value < 1 || pdatum->value > 32);
457 permission_names[pdatum->value - 1] = (char *)k;
462 static void security_dump_masked_av(struct context *scontext,
463 struct context *tcontext,
468 struct common_datum *common_dat;
469 struct class_datum *tclass_dat;
470 struct audit_buffer *ab;
472 char *scontext_name = NULL;
473 char *tcontext_name = NULL;
474 char *permission_names[32];
477 bool need_comma = false;
482 tclass_name = sym_name(&policydb, SYM_CLASSES, tclass - 1);
483 tclass_dat = policydb.class_val_to_struct[tclass - 1];
484 common_dat = tclass_dat->comdatum;
486 /* init permission_names */
488 hashtab_map(common_dat->permissions.table,
489 dump_masked_av_helper, permission_names) < 0)
492 if (hashtab_map(tclass_dat->permissions.table,
493 dump_masked_av_helper, permission_names) < 0)
496 /* get scontext/tcontext in text form */
497 if (context_struct_to_string(scontext,
498 &scontext_name, &length) < 0)
501 if (context_struct_to_string(tcontext,
502 &tcontext_name, &length) < 0)
505 /* audit a message */
506 ab = audit_log_start(current->audit_context,
507 GFP_ATOMIC, AUDIT_SELINUX_ERR);
511 audit_log_format(ab, "op=security_compute_av reason=%s "
512 "scontext=%s tcontext=%s tclass=%s perms=",
513 reason, scontext_name, tcontext_name, tclass_name);
515 for (index = 0; index < 32; index++) {
516 u32 mask = (1 << index);
518 if ((mask & permissions) == 0)
521 audit_log_format(ab, "%s%s",
522 need_comma ? "," : "",
523 permission_names[index]
524 ? permission_names[index] : "????");
529 /* release scontext/tcontext */
530 kfree(tcontext_name);
531 kfree(scontext_name);
537 * security_boundary_permission - drops violated permissions
538 * on boundary constraint.
540 static void type_attribute_bounds_av(struct context *scontext,
541 struct context *tcontext,
543 struct av_decision *avd)
545 struct context lo_scontext;
546 struct context lo_tcontext;
547 struct av_decision lo_avd;
548 struct type_datum *source;
549 struct type_datum *target;
552 source = flex_array_get_ptr(policydb.type_val_to_struct_array,
556 target = flex_array_get_ptr(policydb.type_val_to_struct_array,
560 if (source->bounds) {
561 memset(&lo_avd, 0, sizeof(lo_avd));
563 memcpy(&lo_scontext, scontext, sizeof(lo_scontext));
564 lo_scontext.type = source->bounds;
566 context_struct_compute_av(&lo_scontext,
570 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
571 return; /* no masked permission */
572 masked = ~lo_avd.allowed & avd->allowed;
575 if (target->bounds) {
576 memset(&lo_avd, 0, sizeof(lo_avd));
578 memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext));
579 lo_tcontext.type = target->bounds;
581 context_struct_compute_av(scontext,
585 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
586 return; /* no masked permission */
587 masked = ~lo_avd.allowed & avd->allowed;
590 if (source->bounds && target->bounds) {
591 memset(&lo_avd, 0, sizeof(lo_avd));
593 * lo_scontext and lo_tcontext are already
597 context_struct_compute_av(&lo_scontext,
601 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
602 return; /* no masked permission */
603 masked = ~lo_avd.allowed & avd->allowed;
607 /* mask violated permissions */
608 avd->allowed &= ~masked;
610 /* audit masked permissions */
611 security_dump_masked_av(scontext, tcontext,
612 tclass, masked, "bounds");
617 * Compute access vectors based on a context structure pair for
618 * the permissions in a particular class.
620 static void context_struct_compute_av(struct context *scontext,
621 struct context *tcontext,
623 struct av_decision *avd)
625 struct constraint_node *constraint;
626 struct role_allow *ra;
627 struct avtab_key avkey;
628 struct avtab_node *node;
629 struct class_datum *tclass_datum;
630 struct ebitmap *sattr, *tattr;
631 struct ebitmap_node *snode, *tnode;
636 avd->auditdeny = 0xffffffff;
638 if (unlikely(!tclass || tclass > policydb.p_classes.nprim)) {
639 if (printk_ratelimit())
640 printk(KERN_WARNING "SELinux: Invalid class %hu\n", tclass);
644 tclass_datum = policydb.class_val_to_struct[tclass - 1];
647 * If a specific type enforcement rule was defined for
648 * this permission check, then use it.
650 avkey.target_class = tclass;
651 avkey.specified = AVTAB_AV;
652 sattr = flex_array_get(policydb.type_attr_map_array, scontext->type - 1);
654 tattr = flex_array_get(policydb.type_attr_map_array, tcontext->type - 1);
656 ebitmap_for_each_positive_bit(sattr, snode, i) {
657 ebitmap_for_each_positive_bit(tattr, tnode, j) {
658 avkey.source_type = i + 1;
659 avkey.target_type = j + 1;
660 for (node = avtab_search_node(&policydb.te_avtab, &avkey);
662 node = avtab_search_node_next(node, avkey.specified)) {
663 if (node->key.specified == AVTAB_ALLOWED)
664 avd->allowed |= node->datum.data;
665 else if (node->key.specified == AVTAB_AUDITALLOW)
666 avd->auditallow |= node->datum.data;
667 else if (node->key.specified == AVTAB_AUDITDENY)
668 avd->auditdeny &= node->datum.data;
671 /* Check conditional av table for additional permissions */
672 cond_compute_av(&policydb.te_cond_avtab, &avkey, avd);
678 * Remove any permissions prohibited by a constraint (this includes
681 constraint = tclass_datum->constraints;
683 if ((constraint->permissions & (avd->allowed)) &&
684 !constraint_expr_eval(scontext, tcontext, NULL,
686 avd->allowed &= ~(constraint->permissions);
688 constraint = constraint->next;
692 * If checking process transition permission and the
693 * role is changing, then check the (current_role, new_role)
696 if (tclass == policydb.process_class &&
697 (avd->allowed & policydb.process_trans_perms) &&
698 scontext->role != tcontext->role) {
699 for (ra = policydb.role_allow; ra; ra = ra->next) {
700 if (scontext->role == ra->role &&
701 tcontext->role == ra->new_role)
705 avd->allowed &= ~policydb.process_trans_perms;
709 * If the given source and target types have boundary
710 * constraint, lazy checks have to mask any violated
711 * permission and notice it to userspace via audit.
713 type_attribute_bounds_av(scontext, tcontext,
717 static int security_validtrans_handle_fail(struct context *ocontext,
718 struct context *ncontext,
719 struct context *tcontext,
722 char *o = NULL, *n = NULL, *t = NULL;
723 u32 olen, nlen, tlen;
725 if (context_struct_to_string(ocontext, &o, &olen))
727 if (context_struct_to_string(ncontext, &n, &nlen))
729 if (context_struct_to_string(tcontext, &t, &tlen))
731 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
732 "security_validate_transition: denied for"
733 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
734 o, n, t, sym_name(&policydb, SYM_CLASSES, tclass-1));
740 if (!selinux_enforcing)
745 int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
748 struct context *ocontext;
749 struct context *ncontext;
750 struct context *tcontext;
751 struct class_datum *tclass_datum;
752 struct constraint_node *constraint;
759 read_lock(&policy_rwlock);
761 tclass = unmap_class(orig_tclass);
763 if (!tclass || tclass > policydb.p_classes.nprim) {
764 printk(KERN_ERR "SELinux: %s: unrecognized class %d\n",
769 tclass_datum = policydb.class_val_to_struct[tclass - 1];
771 ocontext = sidtab_search(&sidtab, oldsid);
773 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
779 ncontext = sidtab_search(&sidtab, newsid);
781 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
787 tcontext = sidtab_search(&sidtab, tasksid);
789 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
795 constraint = tclass_datum->validatetrans;
797 if (!constraint_expr_eval(ocontext, ncontext, tcontext,
799 rc = security_validtrans_handle_fail(ocontext, ncontext,
803 constraint = constraint->next;
807 read_unlock(&policy_rwlock);
812 * security_bounded_transition - check whether the given
813 * transition is directed to bounded, or not.
814 * It returns 0, if @newsid is bounded by @oldsid.
815 * Otherwise, it returns error code.
817 * @oldsid : current security identifier
818 * @newsid : destinated security identifier
820 int security_bounded_transition(u32 old_sid, u32 new_sid)
822 struct context *old_context, *new_context;
823 struct type_datum *type;
827 read_lock(&policy_rwlock);
830 old_context = sidtab_search(&sidtab, old_sid);
832 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
838 new_context = sidtab_search(&sidtab, new_sid);
840 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
846 /* type/domain unchanged */
847 if (old_context->type == new_context->type)
850 index = new_context->type;
852 type = flex_array_get_ptr(policydb.type_val_to_struct_array,
856 /* not bounded anymore */
861 /* @newsid is bounded by @oldsid */
863 if (type->bounds == old_context->type)
866 index = type->bounds;
870 char *old_name = NULL;
871 char *new_name = NULL;
874 if (!context_struct_to_string(old_context,
875 &old_name, &length) &&
876 !context_struct_to_string(new_context,
877 &new_name, &length)) {
878 audit_log(current->audit_context,
879 GFP_ATOMIC, AUDIT_SELINUX_ERR,
880 "op=security_bounded_transition "
882 "oldcontext=%s newcontext=%s",
889 read_unlock(&policy_rwlock);
894 static void avd_init(struct av_decision *avd)
898 avd->auditdeny = 0xffffffff;
899 avd->seqno = latest_granting;
905 * security_compute_av - Compute access vector decisions.
906 * @ssid: source security identifier
907 * @tsid: target security identifier
908 * @tclass: target security class
909 * @avd: access vector decisions
911 * Compute a set of access vector decisions based on the
912 * SID pair (@ssid, @tsid) for the permissions in @tclass.
914 void security_compute_av(u32 ssid,
917 struct av_decision *avd)
920 struct context *scontext = NULL, *tcontext = NULL;
922 read_lock(&policy_rwlock);
927 scontext = sidtab_search(&sidtab, ssid);
929 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
934 /* permissive domain? */
935 if (ebitmap_get_bit(&policydb.permissive_map, scontext->type))
936 avd->flags |= AVD_FLAGS_PERMISSIVE;
938 tcontext = sidtab_search(&sidtab, tsid);
940 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
945 tclass = unmap_class(orig_tclass);
946 if (unlikely(orig_tclass && !tclass)) {
947 if (policydb.allow_unknown)
951 context_struct_compute_av(scontext, tcontext, tclass, avd);
952 map_decision(orig_tclass, avd, policydb.allow_unknown);
954 read_unlock(&policy_rwlock);
957 avd->allowed = 0xffffffff;
961 void security_compute_av_user(u32 ssid,
964 struct av_decision *avd)
966 struct context *scontext = NULL, *tcontext = NULL;
968 read_lock(&policy_rwlock);
973 scontext = sidtab_search(&sidtab, ssid);
975 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
980 /* permissive domain? */
981 if (ebitmap_get_bit(&policydb.permissive_map, scontext->type))
982 avd->flags |= AVD_FLAGS_PERMISSIVE;
984 tcontext = sidtab_search(&sidtab, tsid);
986 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
991 if (unlikely(!tclass)) {
992 if (policydb.allow_unknown)
997 context_struct_compute_av(scontext, tcontext, tclass, avd);
999 read_unlock(&policy_rwlock);
1002 avd->allowed = 0xffffffff;
1007 * Write the security context string representation of
1008 * the context structure `context' into a dynamically
1009 * allocated string of the correct size. Set `*scontext'
1010 * to point to this string and set `*scontext_len' to
1011 * the length of the string.
1013 static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
1022 *scontext_len = context->len;
1023 *scontext = kstrdup(context->str, GFP_ATOMIC);
1029 /* Compute the size of the context. */
1030 *scontext_len += strlen(sym_name(&policydb, SYM_USERS, context->user - 1)) + 1;
1031 *scontext_len += strlen(sym_name(&policydb, SYM_ROLES, context->role - 1)) + 1;
1032 *scontext_len += strlen(sym_name(&policydb, SYM_TYPES, context->type - 1)) + 1;
1033 *scontext_len += mls_compute_context_len(context);
1038 /* Allocate space for the context; caller must free this space. */
1039 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1042 *scontext = scontextp;
1045 * Copy the user name, role name and type name into the context.
1047 sprintf(scontextp, "%s:%s:%s",
1048 sym_name(&policydb, SYM_USERS, context->user - 1),
1049 sym_name(&policydb, SYM_ROLES, context->role - 1),
1050 sym_name(&policydb, SYM_TYPES, context->type - 1));
1051 scontextp += strlen(sym_name(&policydb, SYM_USERS, context->user - 1)) +
1052 1 + strlen(sym_name(&policydb, SYM_ROLES, context->role - 1)) +
1053 1 + strlen(sym_name(&policydb, SYM_TYPES, context->type - 1));
1055 mls_sid_to_context(context, &scontextp);
1062 #include "initial_sid_to_string.h"
1064 const char *security_get_initial_sid_context(u32 sid)
1066 if (unlikely(sid > SECINITSID_NUM))
1068 return initial_sid_to_string[sid];
1071 static int security_sid_to_context_core(u32 sid, char **scontext,
1072 u32 *scontext_len, int force)
1074 struct context *context;
1081 if (!ss_initialized) {
1082 if (sid <= SECINITSID_NUM) {
1085 *scontext_len = strlen(initial_sid_to_string[sid]) + 1;
1088 scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
1093 strcpy(scontextp, initial_sid_to_string[sid]);
1094 *scontext = scontextp;
1097 printk(KERN_ERR "SELinux: %s: called before initial "
1098 "load_policy on unknown SID %d\n", __func__, sid);
1102 read_lock(&policy_rwlock);
1104 context = sidtab_search_force(&sidtab, sid);
1106 context = sidtab_search(&sidtab, sid);
1108 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1113 rc = context_struct_to_string(context, scontext, scontext_len);
1115 read_unlock(&policy_rwlock);
1122 * security_sid_to_context - Obtain a context for a given SID.
1123 * @sid: security identifier, SID
1124 * @scontext: security context
1125 * @scontext_len: length in bytes
1127 * Write the string representation of the context associated with @sid
1128 * into a dynamically allocated string of the correct size. Set @scontext
1129 * to point to this string and set @scontext_len to the length of the string.
1131 int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
1133 return security_sid_to_context_core(sid, scontext, scontext_len, 0);
1136 int security_sid_to_context_force(u32 sid, char **scontext, u32 *scontext_len)
1138 return security_sid_to_context_core(sid, scontext, scontext_len, 1);
1142 * Caveat: Mutates scontext.
1144 static int string_to_context_struct(struct policydb *pol,
1145 struct sidtab *sidtabp,
1148 struct context *ctx,
1151 struct role_datum *role;
1152 struct type_datum *typdatum;
1153 struct user_datum *usrdatum;
1154 char *scontextp, *p, oldc;
1159 /* Parse the security context. */
1162 scontextp = (char *) scontext;
1164 /* Extract the user. */
1166 while (*p && *p != ':')
1174 usrdatum = hashtab_search(pol->p_users.table, scontextp);
1178 ctx->user = usrdatum->value;
1182 while (*p && *p != ':')
1190 role = hashtab_search(pol->p_roles.table, scontextp);
1193 ctx->role = role->value;
1197 while (*p && *p != ':')
1202 typdatum = hashtab_search(pol->p_types.table, scontextp);
1203 if (!typdatum || typdatum->attribute)
1206 ctx->type = typdatum->value;
1208 rc = mls_context_to_sid(pol, oldc, &p, ctx, sidtabp, def_sid);
1213 if ((p - scontext) < scontext_len)
1216 /* Check the validity of the new context. */
1217 if (!policydb_context_isvalid(pol, ctx))
1222 context_destroy(ctx);
1226 static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
1227 u32 *sid, u32 def_sid, gfp_t gfp_flags,
1230 char *scontext2, *str = NULL;
1231 struct context context;
1234 if (!ss_initialized) {
1237 for (i = 1; i < SECINITSID_NUM; i++) {
1238 if (!strcmp(initial_sid_to_string[i], scontext)) {
1243 *sid = SECINITSID_KERNEL;
1248 /* Copy the string so that we can modify the copy as we parse it. */
1249 scontext2 = kmalloc(scontext_len + 1, gfp_flags);
1252 memcpy(scontext2, scontext, scontext_len);
1253 scontext2[scontext_len] = 0;
1256 /* Save another copy for storing in uninterpreted form */
1258 str = kstrdup(scontext2, gfp_flags);
1263 read_lock(&policy_rwlock);
1264 rc = string_to_context_struct(&policydb, &sidtab, scontext2,
1265 scontext_len, &context, def_sid);
1266 if (rc == -EINVAL && force) {
1268 context.len = scontext_len;
1272 rc = sidtab_context_to_sid(&sidtab, &context, sid);
1273 context_destroy(&context);
1275 read_unlock(&policy_rwlock);
1283 * security_context_to_sid - Obtain a SID for a given security context.
1284 * @scontext: security context
1285 * @scontext_len: length in bytes
1286 * @sid: security identifier, SID
1288 * Obtains a SID associated with the security context that
1289 * has the string representation specified by @scontext.
1290 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1291 * memory is available, or 0 on success.
1293 int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid)
1295 return security_context_to_sid_core(scontext, scontext_len,
1296 sid, SECSID_NULL, GFP_KERNEL, 0);
1300 * security_context_to_sid_default - Obtain a SID for a given security context,
1301 * falling back to specified default if needed.
1303 * @scontext: security context
1304 * @scontext_len: length in bytes
1305 * @sid: security identifier, SID
1306 * @def_sid: default SID to assign on error
1308 * Obtains a SID associated with the security context that
1309 * has the string representation specified by @scontext.
1310 * The default SID is passed to the MLS layer to be used to allow
1311 * kernel labeling of the MLS field if the MLS field is not present
1312 * (for upgrading to MLS without full relabel).
1313 * Implicitly forces adding of the context even if it cannot be mapped yet.
1314 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1315 * memory is available, or 0 on success.
1317 int security_context_to_sid_default(const char *scontext, u32 scontext_len,
1318 u32 *sid, u32 def_sid, gfp_t gfp_flags)
1320 return security_context_to_sid_core(scontext, scontext_len,
1321 sid, def_sid, gfp_flags, 1);
1324 int security_context_to_sid_force(const char *scontext, u32 scontext_len,
1327 return security_context_to_sid_core(scontext, scontext_len,
1328 sid, SECSID_NULL, GFP_KERNEL, 1);
1331 static int compute_sid_handle_invalid_context(
1332 struct context *scontext,
1333 struct context *tcontext,
1335 struct context *newcontext)
1337 char *s = NULL, *t = NULL, *n = NULL;
1338 u32 slen, tlen, nlen;
1340 if (context_struct_to_string(scontext, &s, &slen))
1342 if (context_struct_to_string(tcontext, &t, &tlen))
1344 if (context_struct_to_string(newcontext, &n, &nlen))
1346 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
1347 "security_compute_sid: invalid context %s"
1351 n, s, t, sym_name(&policydb, SYM_CLASSES, tclass-1));
1356 if (!selinux_enforcing)
1361 static void filename_compute_type(struct policydb *p, struct context *newcontext,
1362 u32 scon, u32 tcon, u16 tclass,
1363 const struct qstr *qstr)
1365 struct filename_trans *ft;
1366 for (ft = p->filename_trans; ft; ft = ft->next) {
1367 if (ft->stype == scon &&
1368 ft->ttype == tcon &&
1369 ft->tclass == tclass &&
1370 !strcmp(ft->name, qstr->name)) {
1371 newcontext->type = ft->otype;
1377 static int security_compute_sid(u32 ssid,
1381 const struct qstr *qstr,
1385 struct context *scontext = NULL, *tcontext = NULL, newcontext;
1386 struct role_trans *roletr = NULL;
1387 struct avtab_key avkey;
1388 struct avtab_datum *avdatum;
1389 struct avtab_node *node;
1394 if (!ss_initialized) {
1395 switch (orig_tclass) {
1396 case SECCLASS_PROCESS: /* kernel value */
1406 context_init(&newcontext);
1408 read_lock(&policy_rwlock);
1411 tclass = unmap_class(orig_tclass);
1412 sock = security_is_socket_class(orig_tclass);
1414 tclass = orig_tclass;
1415 sock = security_is_socket_class(map_class(tclass));
1418 scontext = sidtab_search(&sidtab, ssid);
1420 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1425 tcontext = sidtab_search(&sidtab, tsid);
1427 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
1433 /* Set the user identity. */
1434 switch (specified) {
1435 case AVTAB_TRANSITION:
1437 /* Use the process user identity. */
1438 newcontext.user = scontext->user;
1441 /* Use the related object owner. */
1442 newcontext.user = tcontext->user;
1446 /* Set the role and type to default values. */
1447 if ((tclass == policydb.process_class) || (sock == true)) {
1448 /* Use the current role and type of process. */
1449 newcontext.role = scontext->role;
1450 newcontext.type = scontext->type;
1452 /* Use the well-defined object role. */
1453 newcontext.role = OBJECT_R_VAL;
1454 /* Use the type of the related object. */
1455 newcontext.type = tcontext->type;
1458 /* Look for a type transition/member/change rule. */
1459 avkey.source_type = scontext->type;
1460 avkey.target_type = tcontext->type;
1461 avkey.target_class = tclass;
1462 avkey.specified = specified;
1463 avdatum = avtab_search(&policydb.te_avtab, &avkey);
1465 /* If no permanent rule, also check for enabled conditional rules */
1467 node = avtab_search_node(&policydb.te_cond_avtab, &avkey);
1468 for (; node; node = avtab_search_node_next(node, specified)) {
1469 if (node->key.specified & AVTAB_ENABLED) {
1470 avdatum = &node->datum;
1477 /* Use the type from the type transition/member/change rule. */
1478 newcontext.type = avdatum->data;
1481 /* if we have a qstr this is a file trans check so check those rules */
1483 filename_compute_type(&policydb, &newcontext, scontext->type,
1484 tcontext->type, tclass, qstr);
1486 /* Check for class-specific changes. */
1487 if (tclass == policydb.process_class) {
1488 if (specified & AVTAB_TRANSITION) {
1489 /* Look for a role transition rule. */
1490 for (roletr = policydb.role_tr; roletr;
1491 roletr = roletr->next) {
1492 if (roletr->role == scontext->role &&
1493 roletr->type == tcontext->type) {
1494 /* Use the role transition rule. */
1495 newcontext.role = roletr->new_role;
1502 /* Set the MLS attributes.
1503 This is done last because it may allocate memory. */
1504 rc = mls_compute_sid(scontext, tcontext, tclass, specified,
1509 /* Check the validity of the context. */
1510 if (!policydb_context_isvalid(&policydb, &newcontext)) {
1511 rc = compute_sid_handle_invalid_context(scontext,
1518 /* Obtain the sid for the context. */
1519 rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid);
1521 read_unlock(&policy_rwlock);
1522 context_destroy(&newcontext);
1528 * security_transition_sid - Compute the SID for a new subject/object.
1529 * @ssid: source security identifier
1530 * @tsid: target security identifier
1531 * @tclass: target security class
1532 * @out_sid: security identifier for new subject/object
1534 * Compute a SID to use for labeling a new subject or object in the
1535 * class @tclass based on a SID pair (@ssid, @tsid).
1536 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1537 * if insufficient memory is available, or %0 if the new SID was
1538 * computed successfully.
1540 int security_transition_sid(u32 ssid, u32 tsid, u16 tclass,
1541 const struct qstr *qstr, u32 *out_sid)
1543 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
1544 qstr, out_sid, true);
1547 int security_transition_sid_user(u32 ssid, u32 tsid, u16 tclass, u32 *out_sid)
1549 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
1550 NULL, out_sid, false);
1554 * security_member_sid - Compute the SID for member selection.
1555 * @ssid: source security identifier
1556 * @tsid: target security identifier
1557 * @tclass: target security class
1558 * @out_sid: security identifier for selected member
1560 * Compute a SID to use when selecting a member of a polyinstantiated
1561 * object of class @tclass based on a SID pair (@ssid, @tsid).
1562 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1563 * if insufficient memory is available, or %0 if the SID was
1564 * computed successfully.
1566 int security_member_sid(u32 ssid,
1571 return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, NULL,
1576 * security_change_sid - Compute the SID for object relabeling.
1577 * @ssid: source security identifier
1578 * @tsid: target security identifier
1579 * @tclass: target security class
1580 * @out_sid: security identifier for selected member
1582 * Compute a SID to use for relabeling an object of class @tclass
1583 * based on a SID pair (@ssid, @tsid).
1584 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1585 * if insufficient memory is available, or %0 if the SID was
1586 * computed successfully.
1588 int security_change_sid(u32 ssid,
1593 return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, NULL,
1597 /* Clone the SID into the new SID table. */
1598 static int clone_sid(u32 sid,
1599 struct context *context,
1602 struct sidtab *s = arg;
1604 if (sid > SECINITSID_NUM)
1605 return sidtab_insert(s, sid, context);
1610 static inline int convert_context_handle_invalid_context(struct context *context)
1615 if (selinux_enforcing)
1618 if (!context_struct_to_string(context, &s, &len)) {
1619 printk(KERN_WARNING "SELinux: Context %s would be invalid if enforcing\n", s);
1625 struct convert_context_args {
1626 struct policydb *oldp;
1627 struct policydb *newp;
1631 * Convert the values in the security context
1632 * structure `c' from the values specified
1633 * in the policy `p->oldp' to the values specified
1634 * in the policy `p->newp'. Verify that the
1635 * context is valid under the new policy.
1637 static int convert_context(u32 key,
1641 struct convert_context_args *args;
1642 struct context oldc;
1643 struct ocontext *oc;
1644 struct mls_range *range;
1645 struct role_datum *role;
1646 struct type_datum *typdatum;
1647 struct user_datum *usrdatum;
1652 if (key <= SECINITSID_NUM)
1661 s = kstrdup(c->str, GFP_KERNEL);
1665 rc = string_to_context_struct(args->newp, NULL, s,
1666 c->len, &ctx, SECSID_NULL);
1669 printk(KERN_INFO "SELinux: Context %s became valid (mapped).\n",
1671 /* Replace string with mapped representation. */
1673 memcpy(c, &ctx, sizeof(*c));
1675 } else if (rc == -EINVAL) {
1676 /* Retain string representation for later mapping. */
1680 /* Other error condition, e.g. ENOMEM. */
1681 printk(KERN_ERR "SELinux: Unable to map context %s, rc = %d.\n",
1687 rc = context_cpy(&oldc, c);
1691 /* Convert the user. */
1693 usrdatum = hashtab_search(args->newp->p_users.table,
1694 sym_name(args->oldp, SYM_USERS, c->user - 1));
1697 c->user = usrdatum->value;
1699 /* Convert the role. */
1701 role = hashtab_search(args->newp->p_roles.table,
1702 sym_name(args->oldp, SYM_ROLES, c->role - 1));
1705 c->role = role->value;
1707 /* Convert the type. */
1709 typdatum = hashtab_search(args->newp->p_types.table,
1710 sym_name(args->oldp, SYM_TYPES, c->type - 1));
1713 c->type = typdatum->value;
1715 /* Convert the MLS fields if dealing with MLS policies */
1716 if (args->oldp->mls_enabled && args->newp->mls_enabled) {
1717 rc = mls_convert_context(args->oldp, args->newp, c);
1720 } else if (args->oldp->mls_enabled && !args->newp->mls_enabled) {
1722 * Switching between MLS and non-MLS policy:
1723 * free any storage used by the MLS fields in the
1724 * context for all existing entries in the sidtab.
1726 mls_context_destroy(c);
1727 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) {
1729 * Switching between non-MLS and MLS policy:
1730 * ensure that the MLS fields of the context for all
1731 * existing entries in the sidtab are filled in with a
1732 * suitable default value, likely taken from one of the
1735 oc = args->newp->ocontexts[OCON_ISID];
1736 while (oc && oc->sid[0] != SECINITSID_UNLABELED)
1740 printk(KERN_ERR "SELinux: unable to look up"
1741 " the initial SIDs list\n");
1744 range = &oc->context[0].range;
1745 rc = mls_range_set(c, range);
1750 /* Check the validity of the new context. */
1751 if (!policydb_context_isvalid(args->newp, c)) {
1752 rc = convert_context_handle_invalid_context(&oldc);
1757 context_destroy(&oldc);
1763 /* Map old representation to string and save it. */
1764 rc = context_struct_to_string(&oldc, &s, &len);
1767 context_destroy(&oldc);
1771 printk(KERN_INFO "SELinux: Context %s became invalid (unmapped).\n",
1777 static void security_load_policycaps(void)
1779 selinux_policycap_netpeer = ebitmap_get_bit(&policydb.policycaps,
1780 POLICYDB_CAPABILITY_NETPEER);
1781 selinux_policycap_openperm = ebitmap_get_bit(&policydb.policycaps,
1782 POLICYDB_CAPABILITY_OPENPERM);
1785 extern void selinux_complete_init(void);
1786 static int security_preserve_bools(struct policydb *p);
1789 * security_load_policy - Load a security policy configuration.
1790 * @data: binary policy data
1791 * @len: length of data in bytes
1793 * Load a new set of security policy configuration data,
1794 * validate it and convert the SID table as necessary.
1795 * This function will flush the access vector cache after
1796 * loading the new policy.
1798 int security_load_policy(void *data, size_t len)
1800 struct policydb oldpolicydb, newpolicydb;
1801 struct sidtab oldsidtab, newsidtab;
1802 struct selinux_mapping *oldmap, *map = NULL;
1803 struct convert_context_args args;
1807 struct policy_file file = { data, len }, *fp = &file;
1809 if (!ss_initialized) {
1811 rc = policydb_read(&policydb, fp);
1813 avtab_cache_destroy();
1818 rc = selinux_set_mapping(&policydb, secclass_map,
1820 ¤t_mapping_size);
1822 policydb_destroy(&policydb);
1823 avtab_cache_destroy();
1827 rc = policydb_load_isids(&policydb, &sidtab);
1829 policydb_destroy(&policydb);
1830 avtab_cache_destroy();
1834 security_load_policycaps();
1836 seqno = ++latest_granting;
1837 selinux_complete_init();
1838 avc_ss_reset(seqno);
1839 selnl_notify_policyload(seqno);
1840 selinux_status_update_policyload(seqno);
1841 selinux_netlbl_cache_invalidate();
1842 selinux_xfrm_notify_policyload();
1847 sidtab_hash_eval(&sidtab, "sids");
1850 rc = policydb_read(&newpolicydb, fp);
1854 newpolicydb.len = len;
1855 /* If switching between different policy types, log MLS status */
1856 if (policydb.mls_enabled && !newpolicydb.mls_enabled)
1857 printk(KERN_INFO "SELinux: Disabling MLS support...\n");
1858 else if (!policydb.mls_enabled && newpolicydb.mls_enabled)
1859 printk(KERN_INFO "SELinux: Enabling MLS support...\n");
1861 rc = policydb_load_isids(&newpolicydb, &newsidtab);
1863 printk(KERN_ERR "SELinux: unable to load the initial SIDs\n");
1864 policydb_destroy(&newpolicydb);
1868 rc = selinux_set_mapping(&newpolicydb, secclass_map, &map, &map_size);
1872 rc = security_preserve_bools(&newpolicydb);
1874 printk(KERN_ERR "SELinux: unable to preserve booleans\n");
1878 /* Clone the SID table. */
1879 sidtab_shutdown(&sidtab);
1881 rc = sidtab_map(&sidtab, clone_sid, &newsidtab);
1886 * Convert the internal representations of contexts
1887 * in the new SID table.
1889 args.oldp = &policydb;
1890 args.newp = &newpolicydb;
1891 rc = sidtab_map(&newsidtab, convert_context, &args);
1893 printk(KERN_ERR "SELinux: unable to convert the internal"
1894 " representation of contexts in the new SID"
1899 /* Save the old policydb and SID table to free later. */
1900 memcpy(&oldpolicydb, &policydb, sizeof policydb);
1901 sidtab_set(&oldsidtab, &sidtab);
1903 /* Install the new policydb and SID table. */
1904 write_lock_irq(&policy_rwlock);
1905 memcpy(&policydb, &newpolicydb, sizeof policydb);
1906 sidtab_set(&sidtab, &newsidtab);
1907 security_load_policycaps();
1908 oldmap = current_mapping;
1909 current_mapping = map;
1910 current_mapping_size = map_size;
1911 seqno = ++latest_granting;
1912 write_unlock_irq(&policy_rwlock);
1914 /* Free the old policydb and SID table. */
1915 policydb_destroy(&oldpolicydb);
1916 sidtab_destroy(&oldsidtab);
1919 avc_ss_reset(seqno);
1920 selnl_notify_policyload(seqno);
1921 selinux_status_update_policyload(seqno);
1922 selinux_netlbl_cache_invalidate();
1923 selinux_xfrm_notify_policyload();
1929 sidtab_destroy(&newsidtab);
1930 policydb_destroy(&newpolicydb);
1935 size_t security_policydb_len(void)
1939 read_lock(&policy_rwlock);
1941 read_unlock(&policy_rwlock);
1947 * security_port_sid - Obtain the SID for a port.
1948 * @protocol: protocol number
1949 * @port: port number
1950 * @out_sid: security identifier
1952 int security_port_sid(u8 protocol, u16 port, u32 *out_sid)
1957 read_lock(&policy_rwlock);
1959 c = policydb.ocontexts[OCON_PORT];
1961 if (c->u.port.protocol == protocol &&
1962 c->u.port.low_port <= port &&
1963 c->u.port.high_port >= port)
1970 rc = sidtab_context_to_sid(&sidtab,
1976 *out_sid = c->sid[0];
1978 *out_sid = SECINITSID_PORT;
1982 read_unlock(&policy_rwlock);
1987 * security_netif_sid - Obtain the SID for a network interface.
1988 * @name: interface name
1989 * @if_sid: interface SID
1991 int security_netif_sid(char *name, u32 *if_sid)
1996 read_lock(&policy_rwlock);
1998 c = policydb.ocontexts[OCON_NETIF];
2000 if (strcmp(name, c->u.name) == 0)
2006 if (!c->sid[0] || !c->sid[1]) {
2007 rc = sidtab_context_to_sid(&sidtab,
2012 rc = sidtab_context_to_sid(&sidtab,
2018 *if_sid = c->sid[0];
2020 *if_sid = SECINITSID_NETIF;
2023 read_unlock(&policy_rwlock);
2027 static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
2031 for (i = 0; i < 4; i++)
2032 if (addr[i] != (input[i] & mask[i])) {
2041 * security_node_sid - Obtain the SID for a node (host).
2042 * @domain: communication domain aka address family
2044 * @addrlen: address length in bytes
2045 * @out_sid: security identifier
2047 int security_node_sid(u16 domain,
2055 read_lock(&policy_rwlock);
2062 if (addrlen != sizeof(u32))
2065 addr = *((u32 *)addrp);
2067 c = policydb.ocontexts[OCON_NODE];
2069 if (c->u.node.addr == (addr & c->u.node.mask))
2078 if (addrlen != sizeof(u64) * 2)
2080 c = policydb.ocontexts[OCON_NODE6];
2082 if (match_ipv6_addrmask(addrp, c->u.node6.addr,
2091 *out_sid = SECINITSID_NODE;
2097 rc = sidtab_context_to_sid(&sidtab,
2103 *out_sid = c->sid[0];
2105 *out_sid = SECINITSID_NODE;
2110 read_unlock(&policy_rwlock);
2117 * security_get_user_sids - Obtain reachable SIDs for a user.
2118 * @fromsid: starting SID
2119 * @username: username
2120 * @sids: array of reachable SIDs for user
2121 * @nel: number of elements in @sids
2123 * Generate the set of SIDs for legal security contexts
2124 * for a given user that can be reached by @fromsid.
2125 * Set *@sids to point to a dynamically allocated
2126 * array containing the set of SIDs. Set *@nel to the
2127 * number of elements in the array.
2130 int security_get_user_sids(u32 fromsid,
2135 struct context *fromcon, usercon;
2136 u32 *mysids = NULL, *mysids2, sid;
2137 u32 mynel = 0, maxnel = SIDS_NEL;
2138 struct user_datum *user;
2139 struct role_datum *role;
2140 struct ebitmap_node *rnode, *tnode;
2146 if (!ss_initialized)
2149 read_lock(&policy_rwlock);
2151 context_init(&usercon);
2154 fromcon = sidtab_search(&sidtab, fromsid);
2159 user = hashtab_search(policydb.p_users.table, username);
2163 usercon.user = user->value;
2166 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
2170 ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
2171 role = policydb.role_val_to_struct[i];
2172 usercon.role = i + 1;
2173 ebitmap_for_each_positive_bit(&role->types, tnode, j) {
2174 usercon.type = j + 1;
2176 if (mls_setup_user_range(fromcon, user, &usercon))
2179 rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
2182 if (mynel < maxnel) {
2183 mysids[mynel++] = sid;
2187 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
2190 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
2193 mysids[mynel++] = sid;
2199 read_unlock(&policy_rwlock);
2206 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
2211 for (i = 0, j = 0; i < mynel; i++) {
2212 rc = avc_has_perm_noaudit(fromsid, mysids[i],
2213 SECCLASS_PROCESS, /* kernel value */
2214 PROCESS__TRANSITION, AVC_STRICT,
2217 mysids2[j++] = mysids[i];
2229 * security_genfs_sid - Obtain a SID for a file in a filesystem
2230 * @fstype: filesystem type
2231 * @path: path from root of mount
2232 * @sclass: file security class
2233 * @sid: SID for path
2235 * Obtain a SID to use for a file in a filesystem that
2236 * cannot support xattr or use a fixed labeling behavior like
2237 * transition SIDs or task SIDs.
2239 int security_genfs_sid(const char *fstype,
2246 struct genfs *genfs;
2250 while (path[0] == '/' && path[1] == '/')
2253 read_lock(&policy_rwlock);
2255 sclass = unmap_class(orig_sclass);
2256 *sid = SECINITSID_UNLABELED;
2258 for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
2259 cmp = strcmp(fstype, genfs->fstype);
2268 for (c = genfs->head; c; c = c->next) {
2269 len = strlen(c->u.name);
2270 if ((!c->v.sclass || sclass == c->v.sclass) &&
2271 (strncmp(c->u.name, path, len) == 0))
2280 rc = sidtab_context_to_sid(&sidtab, &c->context[0], &c->sid[0]);
2288 read_unlock(&policy_rwlock);
2293 * security_fs_use - Determine how to handle labeling for a filesystem.
2294 * @fstype: filesystem type
2295 * @behavior: labeling behavior
2296 * @sid: SID for filesystem (superblock)
2298 int security_fs_use(
2300 unsigned int *behavior,
2306 read_lock(&policy_rwlock);
2308 c = policydb.ocontexts[OCON_FSUSE];
2310 if (strcmp(fstype, c->u.name) == 0)
2316 *behavior = c->v.behavior;
2318 rc = sidtab_context_to_sid(&sidtab, &c->context[0],
2325 rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid);
2327 *behavior = SECURITY_FS_USE_NONE;
2330 *behavior = SECURITY_FS_USE_GENFS;
2335 read_unlock(&policy_rwlock);
2339 int security_get_bools(int *len, char ***names, int **values)
2343 read_lock(&policy_rwlock);
2348 *len = policydb.p_bools.nprim;
2353 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
2358 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
2362 for (i = 0; i < *len; i++) {
2365 (*values)[i] = policydb.bool_val_to_struct[i]->state;
2366 name_len = strlen(sym_name(&policydb, SYM_BOOLS, i)) + 1;
2369 (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
2373 strncpy((*names)[i], sym_name(&policydb, SYM_BOOLS, i), name_len);
2374 (*names)[i][name_len - 1] = 0;
2378 read_unlock(&policy_rwlock);
2382 for (i = 0; i < *len; i++)
2390 int security_set_bools(int len, int *values)
2393 int lenp, seqno = 0;
2394 struct cond_node *cur;
2396 write_lock_irq(&policy_rwlock);
2399 lenp = policydb.p_bools.nprim;
2403 for (i = 0; i < len; i++) {
2404 if (!!values[i] != policydb.bool_val_to_struct[i]->state) {
2405 audit_log(current->audit_context, GFP_ATOMIC,
2406 AUDIT_MAC_CONFIG_CHANGE,
2407 "bool=%s val=%d old_val=%d auid=%u ses=%u",
2408 sym_name(&policydb, SYM_BOOLS, i),
2410 policydb.bool_val_to_struct[i]->state,
2411 audit_get_loginuid(current),
2412 audit_get_sessionid(current));
2415 policydb.bool_val_to_struct[i]->state = 1;
2417 policydb.bool_val_to_struct[i]->state = 0;
2420 for (cur = policydb.cond_list; cur; cur = cur->next) {
2421 rc = evaluate_cond_node(&policydb, cur);
2426 seqno = ++latest_granting;
2429 write_unlock_irq(&policy_rwlock);
2431 avc_ss_reset(seqno);
2432 selnl_notify_policyload(seqno);
2433 selinux_status_update_policyload(seqno);
2434 selinux_xfrm_notify_policyload();
2439 int security_get_bool_value(int bool)
2444 read_lock(&policy_rwlock);
2447 len = policydb.p_bools.nprim;
2451 rc = policydb.bool_val_to_struct[bool]->state;
2453 read_unlock(&policy_rwlock);
2457 static int security_preserve_bools(struct policydb *p)
2459 int rc, nbools = 0, *bvalues = NULL, i;
2460 char **bnames = NULL;
2461 struct cond_bool_datum *booldatum;
2462 struct cond_node *cur;
2464 rc = security_get_bools(&nbools, &bnames, &bvalues);
2467 for (i = 0; i < nbools; i++) {
2468 booldatum = hashtab_search(p->p_bools.table, bnames[i]);
2470 booldatum->state = bvalues[i];
2472 for (cur = p->cond_list; cur; cur = cur->next) {
2473 rc = evaluate_cond_node(p, cur);
2480 for (i = 0; i < nbools; i++)
2489 * security_sid_mls_copy() - computes a new sid based on the given
2490 * sid and the mls portion of mls_sid.
2492 int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
2494 struct context *context1;
2495 struct context *context2;
2496 struct context newcon;
2502 if (!ss_initialized || !policydb.mls_enabled) {
2507 context_init(&newcon);
2509 read_lock(&policy_rwlock);
2512 context1 = sidtab_search(&sidtab, sid);
2514 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2520 context2 = sidtab_search(&sidtab, mls_sid);
2522 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2527 newcon.user = context1->user;
2528 newcon.role = context1->role;
2529 newcon.type = context1->type;
2530 rc = mls_context_cpy(&newcon, context2);
2534 /* Check the validity of the new context. */
2535 if (!policydb_context_isvalid(&policydb, &newcon)) {
2536 rc = convert_context_handle_invalid_context(&newcon);
2538 if (!context_struct_to_string(&newcon, &s, &len)) {
2539 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2540 "security_sid_mls_copy: invalid context %s", s);
2547 rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid);
2549 read_unlock(&policy_rwlock);
2550 context_destroy(&newcon);
2556 * security_net_peersid_resolve - Compare and resolve two network peer SIDs
2557 * @nlbl_sid: NetLabel SID
2558 * @nlbl_type: NetLabel labeling protocol type
2559 * @xfrm_sid: XFRM SID
2562 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
2563 * resolved into a single SID it is returned via @peer_sid and the function
2564 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function
2565 * returns a negative value. A table summarizing the behavior is below:
2567 * | function return | @sid
2568 * ------------------------------+-----------------+-----------------
2569 * no peer labels | 0 | SECSID_NULL
2570 * single peer label | 0 | <peer_label>
2571 * multiple, consistent labels | 0 | <peer_label>
2572 * multiple, inconsistent labels | -<errno> | SECSID_NULL
2575 int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type,
2580 struct context *nlbl_ctx;
2581 struct context *xfrm_ctx;
2583 *peer_sid = SECSID_NULL;
2585 /* handle the common (which also happens to be the set of easy) cases
2586 * right away, these two if statements catch everything involving a
2587 * single or absent peer SID/label */
2588 if (xfrm_sid == SECSID_NULL) {
2589 *peer_sid = nlbl_sid;
2592 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
2593 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
2595 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
2596 *peer_sid = xfrm_sid;
2600 /* we don't need to check ss_initialized here since the only way both
2601 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
2602 * security server was initialized and ss_initialized was true */
2603 if (!policydb.mls_enabled)
2606 read_lock(&policy_rwlock);
2609 nlbl_ctx = sidtab_search(&sidtab, nlbl_sid);
2611 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2612 __func__, nlbl_sid);
2616 xfrm_ctx = sidtab_search(&sidtab, xfrm_sid);
2618 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n",
2619 __func__, xfrm_sid);
2622 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
2626 /* at present NetLabel SIDs/labels really only carry MLS
2627 * information so if the MLS portion of the NetLabel SID
2628 * matches the MLS portion of the labeled XFRM SID/label
2629 * then pass along the XFRM SID as it is the most
2631 *peer_sid = xfrm_sid;
2633 read_unlock(&policy_rwlock);
2637 static int get_classes_callback(void *k, void *d, void *args)
2639 struct class_datum *datum = d;
2640 char *name = k, **classes = args;
2641 int value = datum->value - 1;
2643 classes[value] = kstrdup(name, GFP_ATOMIC);
2644 if (!classes[value])
2650 int security_get_classes(char ***classes, int *nclasses)
2654 read_lock(&policy_rwlock);
2657 *nclasses = policydb.p_classes.nprim;
2658 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC);
2662 rc = hashtab_map(policydb.p_classes.table, get_classes_callback,
2666 for (i = 0; i < *nclasses; i++)
2667 kfree((*classes)[i]);
2672 read_unlock(&policy_rwlock);
2676 static int get_permissions_callback(void *k, void *d, void *args)
2678 struct perm_datum *datum = d;
2679 char *name = k, **perms = args;
2680 int value = datum->value - 1;
2682 perms[value] = kstrdup(name, GFP_ATOMIC);
2689 int security_get_permissions(char *class, char ***perms, int *nperms)
2692 struct class_datum *match;
2694 read_lock(&policy_rwlock);
2697 match = hashtab_search(policydb.p_classes.table, class);
2699 printk(KERN_ERR "SELinux: %s: unrecognized class %s\n",
2705 *nperms = match->permissions.nprim;
2706 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC);
2710 if (match->comdatum) {
2711 rc = hashtab_map(match->comdatum->permissions.table,
2712 get_permissions_callback, *perms);
2717 rc = hashtab_map(match->permissions.table, get_permissions_callback,
2723 read_unlock(&policy_rwlock);
2727 read_unlock(&policy_rwlock);
2728 for (i = 0; i < *nperms; i++)
2734 int security_get_reject_unknown(void)
2736 return policydb.reject_unknown;
2739 int security_get_allow_unknown(void)
2741 return policydb.allow_unknown;
2745 * security_policycap_supported - Check for a specific policy capability
2746 * @req_cap: capability
2749 * This function queries the currently loaded policy to see if it supports the
2750 * capability specified by @req_cap. Returns true (1) if the capability is
2751 * supported, false (0) if it isn't supported.
2754 int security_policycap_supported(unsigned int req_cap)
2758 read_lock(&policy_rwlock);
2759 rc = ebitmap_get_bit(&policydb.policycaps, req_cap);
2760 read_unlock(&policy_rwlock);
2765 struct selinux_audit_rule {
2767 struct context au_ctxt;
2770 void selinux_audit_rule_free(void *vrule)
2772 struct selinux_audit_rule *rule = vrule;
2775 context_destroy(&rule->au_ctxt);
2780 int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
2782 struct selinux_audit_rule *tmprule;
2783 struct role_datum *roledatum;
2784 struct type_datum *typedatum;
2785 struct user_datum *userdatum;
2786 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
2791 if (!ss_initialized)
2795 case AUDIT_SUBJ_USER:
2796 case AUDIT_SUBJ_ROLE:
2797 case AUDIT_SUBJ_TYPE:
2798 case AUDIT_OBJ_USER:
2799 case AUDIT_OBJ_ROLE:
2800 case AUDIT_OBJ_TYPE:
2801 /* only 'equals' and 'not equals' fit user, role, and type */
2802 if (op != Audit_equal && op != Audit_not_equal)
2805 case AUDIT_SUBJ_SEN:
2806 case AUDIT_SUBJ_CLR:
2807 case AUDIT_OBJ_LEV_LOW:
2808 case AUDIT_OBJ_LEV_HIGH:
2809 /* we do not allow a range, indicated by the presense of '-' */
2810 if (strchr(rulestr, '-'))
2814 /* only the above fields are valid */
2818 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
2822 context_init(&tmprule->au_ctxt);
2824 read_lock(&policy_rwlock);
2826 tmprule->au_seqno = latest_granting;
2829 case AUDIT_SUBJ_USER:
2830 case AUDIT_OBJ_USER:
2832 userdatum = hashtab_search(policydb.p_users.table, rulestr);
2835 tmprule->au_ctxt.user = userdatum->value;
2837 case AUDIT_SUBJ_ROLE:
2838 case AUDIT_OBJ_ROLE:
2840 roledatum = hashtab_search(policydb.p_roles.table, rulestr);
2843 tmprule->au_ctxt.role = roledatum->value;
2845 case AUDIT_SUBJ_TYPE:
2846 case AUDIT_OBJ_TYPE:
2848 typedatum = hashtab_search(policydb.p_types.table, rulestr);
2851 tmprule->au_ctxt.type = typedatum->value;
2853 case AUDIT_SUBJ_SEN:
2854 case AUDIT_SUBJ_CLR:
2855 case AUDIT_OBJ_LEV_LOW:
2856 case AUDIT_OBJ_LEV_HIGH:
2857 rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC);
2864 read_unlock(&policy_rwlock);
2867 selinux_audit_rule_free(tmprule);
2876 /* Check to see if the rule contains any selinux fields */
2877 int selinux_audit_rule_known(struct audit_krule *rule)
2881 for (i = 0; i < rule->field_count; i++) {
2882 struct audit_field *f = &rule->fields[i];
2884 case AUDIT_SUBJ_USER:
2885 case AUDIT_SUBJ_ROLE:
2886 case AUDIT_SUBJ_TYPE:
2887 case AUDIT_SUBJ_SEN:
2888 case AUDIT_SUBJ_CLR:
2889 case AUDIT_OBJ_USER:
2890 case AUDIT_OBJ_ROLE:
2891 case AUDIT_OBJ_TYPE:
2892 case AUDIT_OBJ_LEV_LOW:
2893 case AUDIT_OBJ_LEV_HIGH:
2901 int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule,
2902 struct audit_context *actx)
2904 struct context *ctxt;
2905 struct mls_level *level;
2906 struct selinux_audit_rule *rule = vrule;
2910 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2911 "selinux_audit_rule_match: missing rule\n");
2915 read_lock(&policy_rwlock);
2917 if (rule->au_seqno < latest_granting) {
2918 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2919 "selinux_audit_rule_match: stale rule\n");
2924 ctxt = sidtab_search(&sidtab, sid);
2926 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2927 "selinux_audit_rule_match: unrecognized SID %d\n",
2933 /* a field/op pair that is not caught here will simply fall through
2936 case AUDIT_SUBJ_USER:
2937 case AUDIT_OBJ_USER:
2940 match = (ctxt->user == rule->au_ctxt.user);
2942 case Audit_not_equal:
2943 match = (ctxt->user != rule->au_ctxt.user);
2947 case AUDIT_SUBJ_ROLE:
2948 case AUDIT_OBJ_ROLE:
2951 match = (ctxt->role == rule->au_ctxt.role);
2953 case Audit_not_equal:
2954 match = (ctxt->role != rule->au_ctxt.role);
2958 case AUDIT_SUBJ_TYPE:
2959 case AUDIT_OBJ_TYPE:
2962 match = (ctxt->type == rule->au_ctxt.type);
2964 case Audit_not_equal:
2965 match = (ctxt->type != rule->au_ctxt.type);
2969 case AUDIT_SUBJ_SEN:
2970 case AUDIT_SUBJ_CLR:
2971 case AUDIT_OBJ_LEV_LOW:
2972 case AUDIT_OBJ_LEV_HIGH:
2973 level = ((field == AUDIT_SUBJ_SEN ||
2974 field == AUDIT_OBJ_LEV_LOW) ?
2975 &ctxt->range.level[0] : &ctxt->range.level[1]);
2978 match = mls_level_eq(&rule->au_ctxt.range.level[0],
2981 case Audit_not_equal:
2982 match = !mls_level_eq(&rule->au_ctxt.range.level[0],
2986 match = (mls_level_dom(&rule->au_ctxt.range.level[0],
2988 !mls_level_eq(&rule->au_ctxt.range.level[0],
2992 match = mls_level_dom(&rule->au_ctxt.range.level[0],
2996 match = (mls_level_dom(level,
2997 &rule->au_ctxt.range.level[0]) &&
2998 !mls_level_eq(level,
2999 &rule->au_ctxt.range.level[0]));
3002 match = mls_level_dom(level,
3003 &rule->au_ctxt.range.level[0]);
3009 read_unlock(&policy_rwlock);
3013 static int (*aurule_callback)(void) = audit_update_lsm_rules;
3015 static int aurule_avc_callback(u32 event, u32 ssid, u32 tsid,
3016 u16 class, u32 perms, u32 *retained)
3020 if (event == AVC_CALLBACK_RESET && aurule_callback)
3021 err = aurule_callback();
3025 static int __init aurule_init(void)
3029 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET,
3030 SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0);
3032 panic("avc_add_callback() failed, error %d\n", err);
3036 __initcall(aurule_init);
3038 #ifdef CONFIG_NETLABEL
3040 * security_netlbl_cache_add - Add an entry to the NetLabel cache
3041 * @secattr: the NetLabel packet security attributes
3042 * @sid: the SELinux SID
3045 * Attempt to cache the context in @ctx, which was derived from the packet in
3046 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has
3047 * already been initialized.
3050 static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
3055 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
3056 if (sid_cache == NULL)
3058 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
3059 if (secattr->cache == NULL) {
3065 secattr->cache->free = kfree;
3066 secattr->cache->data = sid_cache;
3067 secattr->flags |= NETLBL_SECATTR_CACHE;
3071 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
3072 * @secattr: the NetLabel packet security attributes
3073 * @sid: the SELinux SID
3076 * Convert the given NetLabel security attributes in @secattr into a
3077 * SELinux SID. If the @secattr field does not contain a full SELinux
3078 * SID/context then use SECINITSID_NETMSG as the foundation. If possibile the
3079 * 'cache' field of @secattr is set and the CACHE flag is set; this is to
3080 * allow the @secattr to be used by NetLabel to cache the secattr to SID
3081 * conversion for future lookups. Returns zero on success, negative values on
3085 int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
3089 struct context *ctx;
3090 struct context ctx_new;
3092 if (!ss_initialized) {
3097 read_lock(&policy_rwlock);
3099 if (secattr->flags & NETLBL_SECATTR_CACHE)
3100 *sid = *(u32 *)secattr->cache->data;
3101 else if (secattr->flags & NETLBL_SECATTR_SECID)
3102 *sid = secattr->attr.secid;
3103 else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
3105 ctx = sidtab_search(&sidtab, SECINITSID_NETMSG);
3109 context_init(&ctx_new);
3110 ctx_new.user = ctx->user;
3111 ctx_new.role = ctx->role;
3112 ctx_new.type = ctx->type;
3113 mls_import_netlbl_lvl(&ctx_new, secattr);
3114 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
3115 rc = ebitmap_netlbl_import(&ctx_new.range.level[0].cat,
3116 secattr->attr.mls.cat);
3119 memcpy(&ctx_new.range.level[1].cat,
3120 &ctx_new.range.level[0].cat,
3121 sizeof(ctx_new.range.level[0].cat));
3124 if (!mls_context_isvalid(&policydb, &ctx_new))
3127 rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
3131 security_netlbl_cache_add(secattr, *sid);
3133 ebitmap_destroy(&ctx_new.range.level[0].cat);
3137 read_unlock(&policy_rwlock);
3140 ebitmap_destroy(&ctx_new.range.level[0].cat);
3142 read_unlock(&policy_rwlock);
3147 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
3148 * @sid: the SELinux SID
3149 * @secattr: the NetLabel packet security attributes
3152 * Convert the given SELinux SID in @sid into a NetLabel security attribute.
3153 * Returns zero on success, negative values on failure.
3156 int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr)
3159 struct context *ctx;
3161 if (!ss_initialized)
3164 read_lock(&policy_rwlock);
3167 ctx = sidtab_search(&sidtab, sid);
3172 secattr->domain = kstrdup(sym_name(&policydb, SYM_TYPES, ctx->type - 1),
3174 if (secattr->domain == NULL)
3177 secattr->attr.secid = sid;
3178 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
3179 mls_export_netlbl_lvl(ctx, secattr);
3180 rc = mls_export_netlbl_cat(ctx, secattr);
3182 read_unlock(&policy_rwlock);
3185 #endif /* CONFIG_NETLABEL */
3188 * security_read_policy - read the policy.
3189 * @data: binary policy data
3190 * @len: length of data in bytes
3193 int security_read_policy(void **data, ssize_t *len)
3196 struct policy_file fp;
3198 if (!ss_initialized)
3201 *len = security_policydb_len();
3203 *data = vmalloc_user(*len);
3210 read_lock(&policy_rwlock);
3211 rc = policydb_write(&policydb, &fp);
3212 read_unlock(&policy_rwlock);
3217 *len = (unsigned long)fp.data - (unsigned long)*data;