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- /*
- * Implementation of the security services.
- *
- * Authors : Stephen Smalley, <sds@epoch.ncsc.mil>
- * James Morris <jmorris@redhat.com>
- *
- * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
- *
- * Support for enhanced MLS infrastructure.
- *
- * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
- *
- * Added conditional policy language extensions
- *
- * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
- * Copyright (C) 2003 - 2004 Tresys Technology, LLC
- * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, version 2.
- */
- #include <linux/kernel.h>
- #include <linux/slab.h>
- #include <linux/string.h>
- #include <linux/spinlock.h>
- #include <linux/errno.h>
- #include <linux/in.h>
- #include <linux/sched.h>
- #include <linux/audit.h>
- #include <linux/mutex.h>
- #include "flask.h"
- #include "avc.h"
- #include "avc_ss.h"
- #include "security.h"
- #include "context.h"
- #include "policydb.h"
- #include "sidtab.h"
- #include "services.h"
- #include "conditional.h"
- #include "mls.h"
- extern void selnl_notify_policyload(u32 seqno);
- unsigned int policydb_loaded_version;
- static DEFINE_RWLOCK(policy_rwlock);
- #define POLICY_RDLOCK read_lock(&policy_rwlock)
- #define POLICY_WRLOCK write_lock_irq(&policy_rwlock)
- #define POLICY_RDUNLOCK read_unlock(&policy_rwlock)
- #define POLICY_WRUNLOCK write_unlock_irq(&policy_rwlock)
- static DEFINE_MUTEX(load_mutex);
- #define LOAD_LOCK mutex_lock(&load_mutex)
- #define LOAD_UNLOCK mutex_unlock(&load_mutex)
- static struct sidtab sidtab;
- struct policydb policydb;
- int ss_initialized = 0;
- /*
- * The largest sequence number that has been used when
- * providing an access decision to the access vector cache.
- * The sequence number only changes when a policy change
- * occurs.
- */
- static u32 latest_granting = 0;
- /* Forward declaration. */
- static int context_struct_to_string(struct context *context, char **scontext,
- u32 *scontext_len);
- /*
- * Return the boolean value of a constraint expression
- * when it is applied to the specified source and target
- * security contexts.
- *
- * xcontext is a special beast... It is used by the validatetrans rules
- * only. For these rules, scontext is the context before the transition,
- * tcontext is the context after the transition, and xcontext is the context
- * of the process performing the transition. All other callers of
- * constraint_expr_eval should pass in NULL for xcontext.
- */
- static int constraint_expr_eval(struct context *scontext,
- struct context *tcontext,
- struct context *xcontext,
- struct constraint_expr *cexpr)
- {
- u32 val1, val2;
- struct context *c;
- struct role_datum *r1, *r2;
- struct mls_level *l1, *l2;
- struct constraint_expr *e;
- int s[CEXPR_MAXDEPTH];
- int sp = -1;
- for (e = cexpr; e; e = e->next) {
- switch (e->expr_type) {
- case CEXPR_NOT:
- BUG_ON(sp < 0);
- s[sp] = !s[sp];
- break;
- case CEXPR_AND:
- BUG_ON(sp < 1);
- sp--;
- s[sp] &= s[sp+1];
- break;
- case CEXPR_OR:
- BUG_ON(sp < 1);
- sp--;
- s[sp] |= s[sp+1];
- break;
- case CEXPR_ATTR:
- if (sp == (CEXPR_MAXDEPTH-1))
- return 0;
- switch (e->attr) {
- case CEXPR_USER:
- val1 = scontext->user;
- val2 = tcontext->user;
- break;
- case CEXPR_TYPE:
- val1 = scontext->type;
- val2 = tcontext->type;
- break;
- case CEXPR_ROLE:
- val1 = scontext->role;
- val2 = tcontext->role;
- r1 = policydb.role_val_to_struct[val1 - 1];
- r2 = policydb.role_val_to_struct[val2 - 1];
- switch (e->op) {
- case CEXPR_DOM:
- s[++sp] = ebitmap_get_bit(&r1->dominates,
- val2 - 1);
- continue;
- case CEXPR_DOMBY:
- s[++sp] = ebitmap_get_bit(&r2->dominates,
- val1 - 1);
- continue;
- case CEXPR_INCOMP:
- s[++sp] = ( !ebitmap_get_bit(&r1->dominates,
- val2 - 1) &&
- !ebitmap_get_bit(&r2->dominates,
- val1 - 1) );
- continue;
- default:
- break;
- }
- break;
- case CEXPR_L1L2:
- l1 = &(scontext->range.level[0]);
- l2 = &(tcontext->range.level[0]);
- goto mls_ops;
- case CEXPR_L1H2:
- l1 = &(scontext->range.level[0]);
- l2 = &(tcontext->range.level[1]);
- goto mls_ops;
- case CEXPR_H1L2:
- l1 = &(scontext->range.level[1]);
- l2 = &(tcontext->range.level[0]);
- goto mls_ops;
- case CEXPR_H1H2:
- l1 = &(scontext->range.level[1]);
- l2 = &(tcontext->range.level[1]);
- goto mls_ops;
- case CEXPR_L1H1:
- l1 = &(scontext->range.level[0]);
- l2 = &(scontext->range.level[1]);
- goto mls_ops;
- case CEXPR_L2H2:
- l1 = &(tcontext->range.level[0]);
- l2 = &(tcontext->range.level[1]);
- goto mls_ops;
- mls_ops:
- switch (e->op) {
- case CEXPR_EQ:
- s[++sp] = mls_level_eq(l1, l2);
- continue;
- case CEXPR_NEQ:
- s[++sp] = !mls_level_eq(l1, l2);
- continue;
- case CEXPR_DOM:
- s[++sp] = mls_level_dom(l1, l2);
- continue;
- case CEXPR_DOMBY:
- s[++sp] = mls_level_dom(l2, l1);
- continue;
- case CEXPR_INCOMP:
- s[++sp] = mls_level_incomp(l2, l1);
- continue;
- default:
- BUG();
- return 0;
- }
- break;
- default:
- BUG();
- return 0;
- }
- switch (e->op) {
- case CEXPR_EQ:
- s[++sp] = (val1 == val2);
- break;
- case CEXPR_NEQ:
- s[++sp] = (val1 != val2);
- break;
- default:
- BUG();
- return 0;
- }
- break;
- case CEXPR_NAMES:
- if (sp == (CEXPR_MAXDEPTH-1))
- return 0;
- c = scontext;
- if (e->attr & CEXPR_TARGET)
- c = tcontext;
- else if (e->attr & CEXPR_XTARGET) {
- c = xcontext;
- if (!c) {
- BUG();
- return 0;
- }
- }
- if (e->attr & CEXPR_USER)
- val1 = c->user;
- else if (e->attr & CEXPR_ROLE)
- val1 = c->role;
- else if (e->attr & CEXPR_TYPE)
- val1 = c->type;
- else {
- BUG();
- return 0;
- }
- switch (e->op) {
- case CEXPR_EQ:
- s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
- break;
- case CEXPR_NEQ:
- s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
- break;
- default:
- BUG();
- return 0;
- }
- break;
- default:
- BUG();
- return 0;
- }
- }
- BUG_ON(sp != 0);
- return s[0];
- }
- /*
- * Compute access vectors based on a context structure pair for
- * the permissions in a particular class.
- */
- static int context_struct_compute_av(struct context *scontext,
- struct context *tcontext,
- u16 tclass,
- u32 requested,
- struct av_decision *avd)
- {
- struct constraint_node *constraint;
- struct role_allow *ra;
- struct avtab_key avkey;
- struct avtab_node *node;
- struct class_datum *tclass_datum;
- struct ebitmap *sattr, *tattr;
- struct ebitmap_node *snode, *tnode;
- unsigned int i, j;
- /*
- * Remap extended Netlink classes for old policy versions.
- * Do this here rather than socket_type_to_security_class()
- * in case a newer policy version is loaded, allowing sockets
- * to remain in the correct class.
- */
- if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
- if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
- tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
- tclass = SECCLASS_NETLINK_SOCKET;
- if (!tclass || tclass > policydb.p_classes.nprim) {
- printk(KERN_ERR "security_compute_av: unrecognized class %d\n",
- tclass);
- return -EINVAL;
- }
- tclass_datum = policydb.class_val_to_struct[tclass - 1];
- /*
- * Initialize the access vectors to the default values.
- */
- avd->allowed = 0;
- avd->decided = 0xffffffff;
- avd->auditallow = 0;
- avd->auditdeny = 0xffffffff;
- avd->seqno = latest_granting;
- /*
- * If a specific type enforcement rule was defined for
- * this permission check, then use it.
- */
- avkey.target_class = tclass;
- avkey.specified = AVTAB_AV;
- sattr = &policydb.type_attr_map[scontext->type - 1];
- tattr = &policydb.type_attr_map[tcontext->type - 1];
- ebitmap_for_each_bit(sattr, snode, i) {
- if (!ebitmap_node_get_bit(snode, i))
- continue;
- ebitmap_for_each_bit(tattr, tnode, j) {
- if (!ebitmap_node_get_bit(tnode, j))
- continue;
- avkey.source_type = i + 1;
- avkey.target_type = j + 1;
- for (node = avtab_search_node(&policydb.te_avtab, &avkey);
- node != NULL;
- node = avtab_search_node_next(node, avkey.specified)) {
- if (node->key.specified == AVTAB_ALLOWED)
- avd->allowed |= node->datum.data;
- else if (node->key.specified == AVTAB_AUDITALLOW)
- avd->auditallow |= node->datum.data;
- else if (node->key.specified == AVTAB_AUDITDENY)
- avd->auditdeny &= node->datum.data;
- }
- /* Check conditional av table for additional permissions */
- cond_compute_av(&policydb.te_cond_avtab, &avkey, avd);
- }
- }
- /*
- * Remove any permissions prohibited by a constraint (this includes
- * the MLS policy).
- */
- constraint = tclass_datum->constraints;
- while (constraint) {
- if ((constraint->permissions & (avd->allowed)) &&
- !constraint_expr_eval(scontext, tcontext, NULL,
- constraint->expr)) {
- avd->allowed = (avd->allowed) & ~(constraint->permissions);
- }
- constraint = constraint->next;
- }
- /*
- * If checking process transition permission and the
- * role is changing, then check the (current_role, new_role)
- * pair.
- */
- if (tclass == SECCLASS_PROCESS &&
- (avd->allowed & (PROCESS__TRANSITION | PROCESS__DYNTRANSITION)) &&
- scontext->role != tcontext->role) {
- for (ra = policydb.role_allow; ra; ra = ra->next) {
- if (scontext->role == ra->role &&
- tcontext->role == ra->new_role)
- break;
- }
- if (!ra)
- avd->allowed = (avd->allowed) & ~(PROCESS__TRANSITION |
- PROCESS__DYNTRANSITION);
- }
- return 0;
- }
- static int security_validtrans_handle_fail(struct context *ocontext,
- struct context *ncontext,
- struct context *tcontext,
- u16 tclass)
- {
- char *o = NULL, *n = NULL, *t = NULL;
- u32 olen, nlen, tlen;
- if (context_struct_to_string(ocontext, &o, &olen) < 0)
- goto out;
- if (context_struct_to_string(ncontext, &n, &nlen) < 0)
- goto out;
- if (context_struct_to_string(tcontext, &t, &tlen) < 0)
- goto out;
- audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
- "security_validate_transition: denied for"
- " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
- o, n, t, policydb.p_class_val_to_name[tclass-1]);
- out:
- kfree(o);
- kfree(n);
- kfree(t);
- if (!selinux_enforcing)
- return 0;
- return -EPERM;
- }
- int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
- u16 tclass)
- {
- struct context *ocontext;
- struct context *ncontext;
- struct context *tcontext;
- struct class_datum *tclass_datum;
- struct constraint_node *constraint;
- int rc = 0;
- if (!ss_initialized)
- return 0;
- POLICY_RDLOCK;
- /*
- * Remap extended Netlink classes for old policy versions.
- * Do this here rather than socket_type_to_security_class()
- * in case a newer policy version is loaded, allowing sockets
- * to remain in the correct class.
- */
- if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
- if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
- tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
- tclass = SECCLASS_NETLINK_SOCKET;
- if (!tclass || tclass > policydb.p_classes.nprim) {
- printk(KERN_ERR "security_validate_transition: "
- "unrecognized class %d\n", tclass);
- rc = -EINVAL;
- goto out;
- }
- tclass_datum = policydb.class_val_to_struct[tclass - 1];
- ocontext = sidtab_search(&sidtab, oldsid);
- if (!ocontext) {
- printk(KERN_ERR "security_validate_transition: "
- " unrecognized SID %d\n", oldsid);
- rc = -EINVAL;
- goto out;
- }
- ncontext = sidtab_search(&sidtab, newsid);
- if (!ncontext) {
- printk(KERN_ERR "security_validate_transition: "
- " unrecognized SID %d\n", newsid);
- rc = -EINVAL;
- goto out;
- }
- tcontext = sidtab_search(&sidtab, tasksid);
- if (!tcontext) {
- printk(KERN_ERR "security_validate_transition: "
- " unrecognized SID %d\n", tasksid);
- rc = -EINVAL;
- goto out;
- }
- constraint = tclass_datum->validatetrans;
- while (constraint) {
- if (!constraint_expr_eval(ocontext, ncontext, tcontext,
- constraint->expr)) {
- rc = security_validtrans_handle_fail(ocontext, ncontext,
- tcontext, tclass);
- goto out;
- }
- constraint = constraint->next;
- }
- out:
- POLICY_RDUNLOCK;
- return rc;
- }
- /**
- * security_compute_av - Compute access vector decisions.
- * @ssid: source security identifier
- * @tsid: target security identifier
- * @tclass: target security class
- * @requested: requested permissions
- * @avd: access vector decisions
- *
- * Compute a set of access vector decisions based on the
- * SID pair (@ssid, @tsid) for the permissions in @tclass.
- * Return -%EINVAL if any of the parameters are invalid or %0
- * if the access vector decisions were computed successfully.
- */
- int security_compute_av(u32 ssid,
- u32 tsid,
- u16 tclass,
- u32 requested,
- struct av_decision *avd)
- {
- struct context *scontext = NULL, *tcontext = NULL;
- int rc = 0;
- if (!ss_initialized) {
- avd->allowed = 0xffffffff;
- avd->decided = 0xffffffff;
- avd->auditallow = 0;
- avd->auditdeny = 0xffffffff;
- avd->seqno = latest_granting;
- return 0;
- }
- POLICY_RDLOCK;
- scontext = sidtab_search(&sidtab, ssid);
- if (!scontext) {
- printk(KERN_ERR "security_compute_av: unrecognized SID %d\n",
- ssid);
- rc = -EINVAL;
- goto out;
- }
- tcontext = sidtab_search(&sidtab, tsid);
- if (!tcontext) {
- printk(KERN_ERR "security_compute_av: unrecognized SID %d\n",
- tsid);
- rc = -EINVAL;
- goto out;
- }
- rc = context_struct_compute_av(scontext, tcontext, tclass,
- requested, avd);
- out:
- POLICY_RDUNLOCK;
- return rc;
- }
- /*
- * Write the security context string representation of
- * the context structure `context' into a dynamically
- * allocated string of the correct size. Set `*scontext'
- * to point to this string and set `*scontext_len' to
- * the length of the string.
- */
- static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
- {
- char *scontextp;
- *scontext = NULL;
- *scontext_len = 0;
- /* Compute the size of the context. */
- *scontext_len += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1;
- *scontext_len += strlen(policydb.p_role_val_to_name[context->role - 1]) + 1;
- *scontext_len += strlen(policydb.p_type_val_to_name[context->type - 1]) + 1;
- *scontext_len += mls_compute_context_len(context);
- /* Allocate space for the context; caller must free this space. */
- scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
- if (!scontextp) {
- return -ENOMEM;
- }
- *scontext = scontextp;
- /*
- * Copy the user name, role name and type name into the context.
- */
- sprintf(scontextp, "%s:%s:%s",
- policydb.p_user_val_to_name[context->user - 1],
- policydb.p_role_val_to_name[context->role - 1],
- policydb.p_type_val_to_name[context->type - 1]);
- scontextp += strlen(policydb.p_user_val_to_name[context->user - 1]) +
- 1 + strlen(policydb.p_role_val_to_name[context->role - 1]) +
- 1 + strlen(policydb.p_type_val_to_name[context->type - 1]);
- mls_sid_to_context(context, &scontextp);
- *scontextp = 0;
- return 0;
- }
- #include "initial_sid_to_string.h"
- /**
- * security_sid_to_context - Obtain a context for a given SID.
- * @sid: security identifier, SID
- * @scontext: security context
- * @scontext_len: length in bytes
- *
- * Write the string representation of the context associated with @sid
- * into a dynamically allocated string of the correct size. Set @scontext
- * to point to this string and set @scontext_len to the length of the string.
- */
- int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
- {
- struct context *context;
- int rc = 0;
- if (!ss_initialized) {
- if (sid <= SECINITSID_NUM) {
- char *scontextp;
- *scontext_len = strlen(initial_sid_to_string[sid]) + 1;
- scontextp = kmalloc(*scontext_len,GFP_ATOMIC);
- strcpy(scontextp, initial_sid_to_string[sid]);
- *scontext = scontextp;
- goto out;
- }
- printk(KERN_ERR "security_sid_to_context: called before initial "
- "load_policy on unknown SID %d\n", sid);
- rc = -EINVAL;
- goto out;
- }
- POLICY_RDLOCK;
- context = sidtab_search(&sidtab, sid);
- if (!context) {
- printk(KERN_ERR "security_sid_to_context: unrecognized SID "
- "%d\n", sid);
- rc = -EINVAL;
- goto out_unlock;
- }
- rc = context_struct_to_string(context, scontext, scontext_len);
- out_unlock:
- POLICY_RDUNLOCK;
- out:
- return rc;
- }
- static int security_context_to_sid_core(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid)
- {
- char *scontext2;
- struct context context;
- struct role_datum *role;
- struct type_datum *typdatum;
- struct user_datum *usrdatum;
- char *scontextp, *p, oldc;
- int rc = 0;
- if (!ss_initialized) {
- int i;
- for (i = 1; i < SECINITSID_NUM; i++) {
- if (!strcmp(initial_sid_to_string[i], scontext)) {
- *sid = i;
- goto out;
- }
- }
- *sid = SECINITSID_KERNEL;
- goto out;
- }
- *sid = SECSID_NULL;
- /* Copy the string so that we can modify the copy as we parse it.
- The string should already by null terminated, but we append a
- null suffix to the copy to avoid problems with the existing
- attr package, which doesn't view the null terminator as part
- of the attribute value. */
- scontext2 = kmalloc(scontext_len+1,GFP_KERNEL);
- if (!scontext2) {
- rc = -ENOMEM;
- goto out;
- }
- memcpy(scontext2, scontext, scontext_len);
- scontext2[scontext_len] = 0;
- context_init(&context);
- *sid = SECSID_NULL;
- POLICY_RDLOCK;
- /* Parse the security context. */
- rc = -EINVAL;
- scontextp = (char *) scontext2;
- /* Extract the user. */
- p = scontextp;
- while (*p && *p != ':')
- p++;
- if (*p == 0)
- goto out_unlock;
- *p++ = 0;
- usrdatum = hashtab_search(policydb.p_users.table, scontextp);
- if (!usrdatum)
- goto out_unlock;
- context.user = usrdatum->value;
- /* Extract role. */
- scontextp = p;
- while (*p && *p != ':')
- p++;
- if (*p == 0)
- goto out_unlock;
- *p++ = 0;
- role = hashtab_search(policydb.p_roles.table, scontextp);
- if (!role)
- goto out_unlock;
- context.role = role->value;
- /* Extract type. */
- scontextp = p;
- while (*p && *p != ':')
- p++;
- oldc = *p;
- *p++ = 0;
- typdatum = hashtab_search(policydb.p_types.table, scontextp);
- if (!typdatum)
- goto out_unlock;
- context.type = typdatum->value;
- rc = mls_context_to_sid(oldc, &p, &context, &sidtab, def_sid);
- if (rc)
- goto out_unlock;
- if ((p - scontext2) < scontext_len) {
- rc = -EINVAL;
- goto out_unlock;
- }
- /* Check the validity of the new context. */
- if (!policydb_context_isvalid(&policydb, &context)) {
- rc = -EINVAL;
- goto out_unlock;
- }
- /* Obtain the new sid. */
- rc = sidtab_context_to_sid(&sidtab, &context, sid);
- out_unlock:
- POLICY_RDUNLOCK;
- context_destroy(&context);
- kfree(scontext2);
- out:
- return rc;
- }
- /**
- * security_context_to_sid - Obtain a SID for a given security context.
- * @scontext: security context
- * @scontext_len: length in bytes
- * @sid: security identifier, SID
- *
- * Obtains a SID associated with the security context that
- * has the string representation specified by @scontext.
- * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
- * memory is available, or 0 on success.
- */
- int security_context_to_sid(char *scontext, u32 scontext_len, u32 *sid)
- {
- return security_context_to_sid_core(scontext, scontext_len,
- sid, SECSID_NULL);
- }
- /**
- * security_context_to_sid_default - Obtain a SID for a given security context,
- * falling back to specified default if needed.
- *
- * @scontext: security context
- * @scontext_len: length in bytes
- * @sid: security identifier, SID
- * @def_sid: default SID to assign on errror
- *
- * Obtains a SID associated with the security context that
- * has the string representation specified by @scontext.
- * The default SID is passed to the MLS layer to be used to allow
- * kernel labeling of the MLS field if the MLS field is not present
- * (for upgrading to MLS without full relabel).
- * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
- * memory is available, or 0 on success.
- */
- int security_context_to_sid_default(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid)
- {
- return security_context_to_sid_core(scontext, scontext_len,
- sid, def_sid);
- }
- static int compute_sid_handle_invalid_context(
- struct context *scontext,
- struct context *tcontext,
- u16 tclass,
- struct context *newcontext)
- {
- char *s = NULL, *t = NULL, *n = NULL;
- u32 slen, tlen, nlen;
- if (context_struct_to_string(scontext, &s, &slen) < 0)
- goto out;
- if (context_struct_to_string(tcontext, &t, &tlen) < 0)
- goto out;
- if (context_struct_to_string(newcontext, &n, &nlen) < 0)
- goto out;
- audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
- "security_compute_sid: invalid context %s"
- " for scontext=%s"
- " tcontext=%s"
- " tclass=%s",
- n, s, t, policydb.p_class_val_to_name[tclass-1]);
- out:
- kfree(s);
- kfree(t);
- kfree(n);
- if (!selinux_enforcing)
- return 0;
- return -EACCES;
- }
- static int security_compute_sid(u32 ssid,
- u32 tsid,
- u16 tclass,
- u32 specified,
- u32 *out_sid)
- {
- struct context *scontext = NULL, *tcontext = NULL, newcontext;
- struct role_trans *roletr = NULL;
- struct avtab_key avkey;
- struct avtab_datum *avdatum;
- struct avtab_node *node;
- int rc = 0;
- if (!ss_initialized) {
- switch (tclass) {
- case SECCLASS_PROCESS:
- *out_sid = ssid;
- break;
- default:
- *out_sid = tsid;
- break;
- }
- goto out;
- }
- POLICY_RDLOCK;
- scontext = sidtab_search(&sidtab, ssid);
- if (!scontext) {
- printk(KERN_ERR "security_compute_sid: unrecognized SID %d\n",
- ssid);
- rc = -EINVAL;
- goto out_unlock;
- }
- tcontext = sidtab_search(&sidtab, tsid);
- if (!tcontext) {
- printk(KERN_ERR "security_compute_sid: unrecognized SID %d\n",
- tsid);
- rc = -EINVAL;
- goto out_unlock;
- }
- context_init(&newcontext);
- /* Set the user identity. */
- switch (specified) {
- case AVTAB_TRANSITION:
- case AVTAB_CHANGE:
- /* Use the process user identity. */
- newcontext.user = scontext->user;
- break;
- case AVTAB_MEMBER:
- /* Use the related object owner. */
- newcontext.user = tcontext->user;
- break;
- }
- /* Set the role and type to default values. */
- switch (tclass) {
- case SECCLASS_PROCESS:
- /* Use the current role and type of process. */
- newcontext.role = scontext->role;
- newcontext.type = scontext->type;
- break;
- default:
- /* Use the well-defined object role. */
- newcontext.role = OBJECT_R_VAL;
- /* Use the type of the related object. */
- newcontext.type = tcontext->type;
- }
- /* Look for a type transition/member/change rule. */
- avkey.source_type = scontext->type;
- avkey.target_type = tcontext->type;
- avkey.target_class = tclass;
- avkey.specified = specified;
- avdatum = avtab_search(&policydb.te_avtab, &avkey);
- /* If no permanent rule, also check for enabled conditional rules */
- if(!avdatum) {
- node = avtab_search_node(&policydb.te_cond_avtab, &avkey);
- for (; node != NULL; node = avtab_search_node_next(node, specified)) {
- if (node->key.specified & AVTAB_ENABLED) {
- avdatum = &node->datum;
- break;
- }
- }
- }
- if (avdatum) {
- /* Use the type from the type transition/member/change rule. */
- newcontext.type = avdatum->data;
- }
- /* Check for class-specific changes. */
- switch (tclass) {
- case SECCLASS_PROCESS:
- if (specified & AVTAB_TRANSITION) {
- /* Look for a role transition rule. */
- for (roletr = policydb.role_tr; roletr;
- roletr = roletr->next) {
- if (roletr->role == scontext->role &&
- roletr->type == tcontext->type) {
- /* Use the role transition rule. */
- newcontext.role = roletr->new_role;
- break;
- }
- }
- }
- break;
- default:
- break;
- }
- /* Set the MLS attributes.
- This is done last because it may allocate memory. */
- rc = mls_compute_sid(scontext, tcontext, tclass, specified, &newcontext);
- if (rc)
- goto out_unlock;
- /* Check the validity of the context. */
- if (!policydb_context_isvalid(&policydb, &newcontext)) {
- rc = compute_sid_handle_invalid_context(scontext,
- tcontext,
- tclass,
- &newcontext);
- if (rc)
- goto out_unlock;
- }
- /* Obtain the sid for the context. */
- rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid);
- out_unlock:
- POLICY_RDUNLOCK;
- context_destroy(&newcontext);
- out:
- return rc;
- }
- /**
- * security_transition_sid - Compute the SID for a new subject/object.
- * @ssid: source security identifier
- * @tsid: target security identifier
- * @tclass: target security class
- * @out_sid: security identifier for new subject/object
- *
- * Compute a SID to use for labeling a new subject or object in the
- * class @tclass based on a SID pair (@ssid, @tsid).
- * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
- * if insufficient memory is available, or %0 if the new SID was
- * computed successfully.
- */
- int security_transition_sid(u32 ssid,
- u32 tsid,
- u16 tclass,
- u32 *out_sid)
- {
- return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, out_sid);
- }
- /**
- * security_member_sid - Compute the SID for member selection.
- * @ssid: source security identifier
- * @tsid: target security identifier
- * @tclass: target security class
- * @out_sid: security identifier for selected member
- *
- * Compute a SID to use when selecting a member of a polyinstantiated
- * object of class @tclass based on a SID pair (@ssid, @tsid).
- * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
- * if insufficient memory is available, or %0 if the SID was
- * computed successfully.
- */
- int security_member_sid(u32 ssid,
- u32 tsid,
- u16 tclass,
- u32 *out_sid)
- {
- return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, out_sid);
- }
- /**
- * security_change_sid - Compute the SID for object relabeling.
- * @ssid: source security identifier
- * @tsid: target security identifier
- * @tclass: target security class
- * @out_sid: security identifier for selected member
- *
- * Compute a SID to use for relabeling an object of class @tclass
- * based on a SID pair (@ssid, @tsid).
- * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
- * if insufficient memory is available, or %0 if the SID was
- * computed successfully.
- */
- int security_change_sid(u32 ssid,
- u32 tsid,
- u16 tclass,
- u32 *out_sid)
- {
- return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, out_sid);
- }
- /*
- * Verify that each permission that is defined under the
- * existing policy is still defined with the same value
- * in the new policy.
- */
- static int validate_perm(void *key, void *datum, void *p)
- {
- struct hashtab *h;
- struct perm_datum *perdatum, *perdatum2;
- int rc = 0;
- h = p;
- perdatum = datum;
- perdatum2 = hashtab_search(h, key);
- if (!perdatum2) {
- printk(KERN_ERR "security: permission %s disappeared",
- (char *)key);
- rc = -ENOENT;
- goto out;
- }
- if (perdatum->value != perdatum2->value) {
- printk(KERN_ERR "security: the value of permission %s changed",
- (char *)key);
- rc = -EINVAL;
- }
- out:
- return rc;
- }
- /*
- * Verify that each class that is defined under the
- * existing policy is still defined with the same
- * attributes in the new policy.
- */
- static int validate_class(void *key, void *datum, void *p)
- {
- struct policydb *newp;
- struct class_datum *cladatum, *cladatum2;
- int rc;
- newp = p;
- cladatum = datum;
- cladatum2 = hashtab_search(newp->p_classes.table, key);
- if (!cladatum2) {
- printk(KERN_ERR "security: class %s disappeared\n",
- (char *)key);
- rc = -ENOENT;
- goto out;
- }
- if (cladatum->value != cladatum2->value) {
- printk(KERN_ERR "security: the value of class %s changed\n",
- (char *)key);
- rc = -EINVAL;
- goto out;
- }
- if ((cladatum->comdatum && !cladatum2->comdatum) ||
- (!cladatum->comdatum && cladatum2->comdatum)) {
- printk(KERN_ERR "security: the inherits clause for the access "
- "vector definition for class %s changed\n", (char *)key);
- rc = -EINVAL;
- goto out;
- }
- if (cladatum->comdatum) {
- rc = hashtab_map(cladatum->comdatum->permissions.table, validate_perm,
- cladatum2->comdatum->permissions.table);
- if (rc) {
- printk(" in the access vector definition for class "
- "%s\n", (char *)key);
- goto out;
- }
- }
- rc = hashtab_map(cladatum->permissions.table, validate_perm,
- cladatum2->permissions.table);
- if (rc)
- printk(" in access vector definition for class %s\n",
- (char *)key);
- out:
- return rc;
- }
- /* Clone the SID into the new SID table. */
- static int clone_sid(u32 sid,
- struct context *context,
- void *arg)
- {
- struct sidtab *s = arg;
- return sidtab_insert(s, sid, context);
- }
- static inline int convert_context_handle_invalid_context(struct context *context)
- {
- int rc = 0;
- if (selinux_enforcing) {
- rc = -EINVAL;
- } else {
- char *s;
- u32 len;
- context_struct_to_string(context, &s, &len);
- printk(KERN_ERR "security: context %s is invalid\n", s);
- kfree(s);
- }
- return rc;
- }
- struct convert_context_args {
- struct policydb *oldp;
- struct policydb *newp;
- };
- /*
- * Convert the values in the security context
- * structure `c' from the values specified
- * in the policy `p->oldp' to the values specified
- * in the policy `p->newp'. Verify that the
- * context is valid under the new policy.
- */
- static int convert_context(u32 key,
- struct context *c,
- void *p)
- {
- struct convert_context_args *args;
- struct context oldc;
- struct role_datum *role;
- struct type_datum *typdatum;
- struct user_datum *usrdatum;
- char *s;
- u32 len;
- int rc;
- args = p;
- rc = context_cpy(&oldc, c);
- if (rc)
- goto out;
- rc = -EINVAL;
- /* Convert the user. */
- usrdatum = hashtab_search(args->newp->p_users.table,
- args->oldp->p_user_val_to_name[c->user - 1]);
- if (!usrdatum) {
- goto bad;
- }
- c->user = usrdatum->value;
- /* Convert the role. */
- role = hashtab_search(args->newp->p_roles.table,
- args->oldp->p_role_val_to_name[c->role - 1]);
- if (!role) {
- goto bad;
- }
- c->role = role->value;
- /* Convert the type. */
- typdatum = hashtab_search(args->newp->p_types.table,
- args->oldp->p_type_val_to_name[c->type - 1]);
- if (!typdatum) {
- goto bad;
- }
- c->type = typdatum->value;
- rc = mls_convert_context(args->oldp, args->newp, c);
- if (rc)
- goto bad;
- /* Check the validity of the new context. */
- if (!policydb_context_isvalid(args->newp, c)) {
- rc = convert_context_handle_invalid_context(&oldc);
- if (rc)
- goto bad;
- }
- context_destroy(&oldc);
- out:
- return rc;
- bad:
- context_struct_to_string(&oldc, &s, &len);
- context_destroy(&oldc);
- printk(KERN_ERR "security: invalidating context %s\n", s);
- kfree(s);
- goto out;
- }
- extern void selinux_complete_init(void);
- /**
- * security_load_policy - Load a security policy configuration.
- * @data: binary policy data
- * @len: length of data in bytes
- *
- * Load a new set of security policy configuration data,
- * validate it and convert the SID table as necessary.
- * This function will flush the access vector cache after
- * loading the new policy.
- */
- int security_load_policy(void *data, size_t len)
- {
- struct policydb oldpolicydb, newpolicydb;
- struct sidtab oldsidtab, newsidtab;
- struct convert_context_args args;
- u32 seqno;
- int rc = 0;
- struct policy_file file = { data, len }, *fp = &file;
- LOAD_LOCK;
- if (!ss_initialized) {
- avtab_cache_init();
- if (policydb_read(&policydb, fp)) {
- LOAD_UNLOCK;
- avtab_cache_destroy();
- return -EINVAL;
- }
- if (policydb_load_isids(&policydb, &sidtab)) {
- LOAD_UNLOCK;
- policydb_destroy(&policydb);
- avtab_cache_destroy();
- return -EINVAL;
- }
- policydb_loaded_version = policydb.policyvers;
- ss_initialized = 1;
- seqno = ++latest_granting;
- LOAD_UNLOCK;
- selinux_complete_init();
- avc_ss_reset(seqno);
- selnl_notify_policyload(seqno);
- return 0;
- }
- #if 0
- sidtab_hash_eval(&sidtab, "sids");
- #endif
- if (policydb_read(&newpolicydb, fp)) {
- LOAD_UNLOCK;
- return -EINVAL;
- }
- sidtab_init(&newsidtab);
- /* Verify that the existing classes did not change. */
- if (hashtab_map(policydb.p_classes.table, validate_class, &newpolicydb)) {
- printk(KERN_ERR "security: the definition of an existing "
- "class changed\n");
- rc = -EINVAL;
- goto err;
- }
- /* Clone the SID table. */
- sidtab_shutdown(&sidtab);
- if (sidtab_map(&sidtab, clone_sid, &newsidtab)) {
- rc = -ENOMEM;
- goto err;
- }
- /* Convert the internal representations of contexts
- in the new SID table and remove invalid SIDs. */
- args.oldp = &policydb;
- args.newp = &newpolicydb;
- sidtab_map_remove_on_error(&newsidtab, convert_context, &args);
- /* Save the old policydb and SID table to free later. */
- memcpy(&oldpolicydb, &policydb, sizeof policydb);
- sidtab_set(&oldsidtab, &sidtab);
- /* Install the new policydb and SID table. */
- POLICY_WRLOCK;
- memcpy(&policydb, &newpolicydb, sizeof policydb);
- sidtab_set(&sidtab, &newsidtab);
- seqno = ++latest_granting;
- policydb_loaded_version = policydb.policyvers;
- POLICY_WRUNLOCK;
- LOAD_UNLOCK;
- /* Free the old policydb and SID table. */
- policydb_destroy(&oldpolicydb);
- sidtab_destroy(&oldsidtab);
- avc_ss_reset(seqno);
- selnl_notify_policyload(seqno);
- return 0;
- err:
- LOAD_UNLOCK;
- sidtab_destroy(&newsidtab);
- policydb_destroy(&newpolicydb);
- return rc;
- }
- /**
- * security_port_sid - Obtain the SID for a port.
- * @domain: communication domain aka address family
- * @type: socket type
- * @protocol: protocol number
- * @port: port number
- * @out_sid: security identifier
- */
- int security_port_sid(u16 domain,
- u16 type,
- u8 protocol,
- u16 port,
- u32 *out_sid)
- {
- struct ocontext *c;
- int rc = 0;
- POLICY_RDLOCK;
- c = policydb.ocontexts[OCON_PORT];
- while (c) {
- if (c->u.port.protocol == protocol &&
- c->u.port.low_port <= port &&
- c->u.port.high_port >= port)
- break;
- c = c->next;
- }
- if (c) {
- if (!c->sid[0]) {
- rc = sidtab_context_to_sid(&sidtab,
- &c->context[0],
- &c->sid[0]);
- if (rc)
- goto out;
- }
- *out_sid = c->sid[0];
- } else {
- *out_sid = SECINITSID_PORT;
- }
- out:
- POLICY_RDUNLOCK;
- return rc;
- }
- /**
- * security_netif_sid - Obtain the SID for a network interface.
- * @name: interface name
- * @if_sid: interface SID
- * @msg_sid: default SID for received packets
- */
- int security_netif_sid(char *name,
- u32 *if_sid,
- u32 *msg_sid)
- {
- int rc = 0;
- struct ocontext *c;
- POLICY_RDLOCK;
- c = policydb.ocontexts[OCON_NETIF];
- while (c) {
- if (strcmp(name, c->u.name) == 0)
- break;
- c = c->next;
- }
- if (c) {
- if (!c->sid[0] || !c->sid[1]) {
- rc = sidtab_context_to_sid(&sidtab,
- &c->context[0],
- &c->sid[0]);
- if (rc)
- goto out;
- rc = sidtab_context_to_sid(&sidtab,
- &c->context[1],
- &c->sid[1]);
- if (rc)
- goto out;
- }
- *if_sid = c->sid[0];
- *msg_sid = c->sid[1];
- } else {
- *if_sid = SECINITSID_NETIF;
- *msg_sid = SECINITSID_NETMSG;
- }
- out:
- POLICY_RDUNLOCK;
- return rc;
- }
- static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
- {
- int i, fail = 0;
- for(i = 0; i < 4; i++)
- if(addr[i] != (input[i] & mask[i])) {
- fail = 1;
- break;
- }
- return !fail;
- }
- /**
- * security_node_sid - Obtain the SID for a node (host).
- * @domain: communication domain aka address family
- * @addrp: address
- * @addrlen: address length in bytes
- * @out_sid: security identifier
- */
- int security_node_sid(u16 domain,
- void *addrp,
- u32 addrlen,
- u32 *out_sid)
- {
- int rc = 0;
- struct ocontext *c;
- POLICY_RDLOCK;
- switch (domain) {
- case AF_INET: {
- u32 addr;
- if (addrlen != sizeof(u32)) {
- rc = -EINVAL;
- goto out;
- }
- addr = *((u32 *)addrp);
- c = policydb.ocontexts[OCON_NODE];
- while (c) {
- if (c->u.node.addr == (addr & c->u.node.mask))
- break;
- c = c->next;
- }
- break;
- }
- case AF_INET6:
- if (addrlen != sizeof(u64) * 2) {
- rc = -EINVAL;
- goto out;
- }
- c = policydb.ocontexts[OCON_NODE6];
- while (c) {
- if (match_ipv6_addrmask(addrp, c->u.node6.addr,
- c->u.node6.mask))
- break;
- c = c->next;
- }
- break;
- default:
- *out_sid = SECINITSID_NODE;
- goto out;
- }
- if (c) {
- if (!c->sid[0]) {
- rc = sidtab_context_to_sid(&sidtab,
- &c->context[0],
- &c->sid[0]);
- if (rc)
- goto out;
- }
- *out_sid = c->sid[0];
- } else {
- *out_sid = SECINITSID_NODE;
- }
- out:
- POLICY_RDUNLOCK;
- return rc;
- }
- #define SIDS_NEL 25
- /**
- * security_get_user_sids - Obtain reachable SIDs for a user.
- * @fromsid: starting SID
- * @username: username
- * @sids: array of reachable SIDs for user
- * @nel: number of elements in @sids
- *
- * Generate the set of SIDs for legal security contexts
- * for a given user that can be reached by @fromsid.
- * Set *@sids to point to a dynamically allocated
- * array containing the set of SIDs. Set *@nel to the
- * number of elements in the array.
- */
- int security_get_user_sids(u32 fromsid,
- char *username,
- u32 **sids,
- u32 *nel)
- {
- struct context *fromcon, usercon;
- u32 *mysids, *mysids2, sid;
- u32 mynel = 0, maxnel = SIDS_NEL;
- struct user_datum *user;
- struct role_datum *role;
- struct av_decision avd;
- struct ebitmap_node *rnode, *tnode;
- int rc = 0, i, j;
- if (!ss_initialized) {
- *sids = NULL;
- *nel = 0;
- goto out;
- }
- POLICY_RDLOCK;
- fromcon = sidtab_search(&sidtab, fromsid);
- if (!fromcon) {
- rc = -EINVAL;
- goto out_unlock;
- }
- user = hashtab_search(policydb.p_users.table, username);
- if (!user) {
- rc = -EINVAL;
- goto out_unlock;
- }
- usercon.user = user->value;
- mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
- if (!mysids) {
- rc = -ENOMEM;
- goto out_unlock;
- }
- ebitmap_for_each_bit(&user->roles, rnode, i) {
- if (!ebitmap_node_get_bit(rnode, i))
- continue;
- role = policydb.role_val_to_struct[i];
- usercon.role = i+1;
- ebitmap_for_each_bit(&role->types, tnode, j) {
- if (!ebitmap_node_get_bit(tnode, j))
- continue;
- usercon.type = j+1;
- if (mls_setup_user_range(fromcon, user, &usercon))
- continue;
- rc = context_struct_compute_av(fromcon, &usercon,
- SECCLASS_PROCESS,
- PROCESS__TRANSITION,
- &avd);
- if (rc || !(avd.allowed & PROCESS__TRANSITION))
- continue;
- rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
- if (rc) {
- kfree(mysids);
- goto out_unlock;
- }
- if (mynel < maxnel) {
- mysids[mynel++] = sid;
- } else {
- maxnel += SIDS_NEL;
- mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
- if (!mysids2) {
- rc = -ENOMEM;
- kfree(mysids);
- goto out_unlock;
- }
- memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
- kfree(mysids);
- mysids = mysids2;
- mysids[mynel++] = sid;
- }
- }
- }
- *sids = mysids;
- *nel = mynel;
- out_unlock:
- POLICY_RDUNLOCK;
- out:
- return rc;
- }
- /**
- * security_genfs_sid - Obtain a SID for a file in a filesystem
- * @fstype: filesystem type
- * @path: path from root of mount
- * @sclass: file security class
- * @sid: SID for path
- *
- * Obtain a SID to use for a file in a filesystem that
- * cannot support xattr or use a fixed labeling behavior like
- * transition SIDs or task SIDs.
- */
- int security_genfs_sid(const char *fstype,
- char *path,
- u16 sclass,
- u32 *sid)
- {
- int len;
- struct genfs *genfs;
- struct ocontext *c;
- int rc = 0, cmp = 0;
- POLICY_RDLOCK;
- for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
- cmp = strcmp(fstype, genfs->fstype);
- if (cmp <= 0)
- break;
- }
- if (!genfs || cmp) {
- *sid = SECINITSID_UNLABELED;
- rc = -ENOENT;
- goto out;
- }
- for (c = genfs->head; c; c = c->next) {
- len = strlen(c->u.name);
- if ((!c->v.sclass || sclass == c->v.sclass) &&
- (strncmp(c->u.name, path, len) == 0))
- break;
- }
- if (!c) {
- *sid = SECINITSID_UNLABELED;
- rc = -ENOENT;
- goto out;
- }
- if (!c->sid[0]) {
- rc = sidtab_context_to_sid(&sidtab,
- &c->context[0],
- &c->sid[0]);
- if (rc)
- goto out;
- }
- *sid = c->sid[0];
- out:
- POLICY_RDUNLOCK;
- return rc;
- }
- /**
- * security_fs_use - Determine how to handle labeling for a filesystem.
- * @fstype: filesystem type
- * @behavior: labeling behavior
- * @sid: SID for filesystem (superblock)
- */
- int security_fs_use(
- const char *fstype,
- unsigned int *behavior,
- u32 *sid)
- {
- int rc = 0;
- struct ocontext *c;
- POLICY_RDLOCK;
- c = policydb.ocontexts[OCON_FSUSE];
- while (c) {
- if (strcmp(fstype, c->u.name) == 0)
- break;
- c = c->next;
- }
- if (c) {
- *behavior = c->v.behavior;
- if (!c->sid[0]) {
- rc = sidtab_context_to_sid(&sidtab,
- &c->context[0],
- &c->sid[0]);
- if (rc)
- goto out;
- }
- *sid = c->sid[0];
- } else {
- rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid);
- if (rc) {
- *behavior = SECURITY_FS_USE_NONE;
- rc = 0;
- } else {
- *behavior = SECURITY_FS_USE_GENFS;
- }
- }
- out:
- POLICY_RDUNLOCK;
- return rc;
- }
- int security_get_bools(int *len, char ***names, int **values)
- {
- int i, rc = -ENOMEM;
- POLICY_RDLOCK;
- *names = NULL;
- *values = NULL;
- *len = policydb.p_bools.nprim;
- if (!*len) {
- rc = 0;
- goto out;
- }
- *names = kcalloc(*len, sizeof(char*), GFP_ATOMIC);
- if (!*names)
- goto err;
- *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
- if (!*values)
- goto err;
- for (i = 0; i < *len; i++) {
- size_t name_len;
- (*values)[i] = policydb.bool_val_to_struct[i]->state;
- name_len = strlen(policydb.p_bool_val_to_name[i]) + 1;
- (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
- if (!(*names)[i])
- goto err;
- strncpy((*names)[i], policydb.p_bool_val_to_name[i], name_len);
- (*names)[i][name_len - 1] = 0;
- }
- rc = 0;
- out:
- POLICY_RDUNLOCK;
- return rc;
- err:
- if (*names) {
- for (i = 0; i < *len; i++)
- kfree((*names)[i]);
- }
- kfree(*values);
- goto out;
- }
- int security_set_bools(int len, int *values)
- {
- int i, rc = 0;
- int lenp, seqno = 0;
- struct cond_node *cur;
- POLICY_WRLOCK;
- lenp = policydb.p_bools.nprim;
- if (len != lenp) {
- rc = -EFAULT;
- goto out;
- }
- for (i = 0; i < len; i++) {
- if (!!values[i] != policydb.bool_val_to_struct[i]->state) {
- audit_log(current->audit_context, GFP_ATOMIC,
- AUDIT_MAC_CONFIG_CHANGE,
- "bool=%s val=%d old_val=%d auid=%u",
- policydb.p_bool_val_to_name[i],
- !!values[i],
- policydb.bool_val_to_struct[i]->state,
- audit_get_loginuid(current->audit_context));
- }
- if (values[i]) {
- policydb.bool_val_to_struct[i]->state = 1;
- } else {
- policydb.bool_val_to_struct[i]->state = 0;
- }
- }
- for (cur = policydb.cond_list; cur != NULL; cur = cur->next) {
- rc = evaluate_cond_node(&policydb, cur);
- if (rc)
- goto out;
- }
- seqno = ++latest_granting;
- out:
- POLICY_WRUNLOCK;
- if (!rc) {
- avc_ss_reset(seqno);
- selnl_notify_policyload(seqno);
- }
- return rc;
- }
- int security_get_bool_value(int bool)
- {
- int rc = 0;
- int len;
- POLICY_RDLOCK;
- len = policydb.p_bools.nprim;
- if (bool >= len) {
- rc = -EFAULT;
- goto out;
- }
- rc = policydb.bool_val_to_struct[bool]->state;
- out:
- POLICY_RDUNLOCK;
- return rc;
- }
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