diff options
Diffstat (limited to 'ANDROID_3.4.5/security/selinux/ss/services.c')
| -rw-r--r-- | ANDROID_3.4.5/security/selinux/ss/services.c | 3226 |
1 files changed, 0 insertions, 3226 deletions
diff --git a/ANDROID_3.4.5/security/selinux/ss/services.c b/ANDROID_3.4.5/security/selinux/ss/services.c deleted file mode 100644 index 185f849a..00000000 --- a/ANDROID_3.4.5/security/selinux/ss/services.c +++ /dev/null @@ -1,3226 +0,0 @@ -/* - * 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. - * Support for context based audit filters. - * - * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com> - * - * Added conditional policy language extensions - * - * Updated: Hewlett-Packard <paul@paul-moore.com> - * - * Added support for NetLabel - * Added support for the policy capability bitmap - * - * Updated: Chad Sellers <csellers@tresys.com> - * - * Added validation of kernel classes and permissions - * - * Updated: KaiGai Kohei <kaigai@ak.jp.nec.com> - * - * Added support for bounds domain and audit messaged on masked permissions - * - * Updated: Guido Trentalancia <guido@trentalancia.com> - * - * Added support for runtime switching of the policy type - * - * Copyright (C) 2008, 2009 NEC Corporation - * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P. - * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc. - * Copyright (C) 2003 - 2004, 2006 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/rcupdate.h> -#include <linux/errno.h> -#include <linux/in.h> -#include <linux/sched.h> -#include <linux/audit.h> -#include <linux/mutex.h> -#include <linux/selinux.h> -#include <linux/flex_array.h> -#include <linux/vmalloc.h> -#include <net/netlabel.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" -#include "objsec.h" -#include "netlabel.h" -#include "xfrm.h" -#include "ebitmap.h" -#include "audit.h" - -int selinux_policycap_netpeer; -int selinux_policycap_openperm; - -static DEFINE_RWLOCK(policy_rwlock); - -static struct sidtab sidtab; -struct policydb policydb; -int ss_initialized; - -/* - * 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; - -/* Forward declaration. */ -static int context_struct_to_string(struct context *context, char **scontext, - u32 *scontext_len); - -static void context_struct_compute_av(struct context *scontext, - struct context *tcontext, - u16 tclass, - struct av_decision *avd); - -struct selinux_mapping { - u16 value; /* policy value */ - unsigned num_perms; - u32 perms[sizeof(u32) * 8]; -}; - -static struct selinux_mapping *current_mapping; -static u16 current_mapping_size; - -static int selinux_set_mapping(struct policydb *pol, - struct security_class_mapping *map, - struct selinux_mapping **out_map_p, - u16 *out_map_size) -{ - struct selinux_mapping *out_map = NULL; - size_t size = sizeof(struct selinux_mapping); - u16 i, j; - unsigned k; - bool print_unknown_handle = false; - - /* Find number of classes in the input mapping */ - if (!map) - return -EINVAL; - i = 0; - while (map[i].name) - i++; - - /* Allocate space for the class records, plus one for class zero */ - out_map = kcalloc(++i, size, GFP_ATOMIC); - if (!out_map) - return -ENOMEM; - - /* Store the raw class and permission values */ - j = 0; - while (map[j].name) { - struct security_class_mapping *p_in = map + (j++); - struct selinux_mapping *p_out = out_map + j; - - /* An empty class string skips ahead */ - if (!strcmp(p_in->name, "")) { - p_out->num_perms = 0; - continue; - } - - p_out->value = string_to_security_class(pol, p_in->name); - if (!p_out->value) { - printk(KERN_INFO - "SELinux: Class %s not defined in policy.\n", - p_in->name); - if (pol->reject_unknown) - goto err; - p_out->num_perms = 0; - print_unknown_handle = true; - continue; - } - - k = 0; - while (p_in->perms && p_in->perms[k]) { - /* An empty permission string skips ahead */ - if (!*p_in->perms[k]) { - k++; - continue; - } - p_out->perms[k] = string_to_av_perm(pol, p_out->value, - p_in->perms[k]); - if (!p_out->perms[k]) { - printk(KERN_INFO - "SELinux: Permission %s in class %s not defined in policy.\n", - p_in->perms[k], p_in->name); - if (pol->reject_unknown) - goto err; - print_unknown_handle = true; - } - - k++; - } - p_out->num_perms = k; - } - - if (print_unknown_handle) - printk(KERN_INFO "SELinux: the above unknown classes and permissions will be %s\n", - pol->allow_unknown ? "allowed" : "denied"); - - *out_map_p = out_map; - *out_map_size = i; - return 0; -err: - kfree(out_map); - return -EINVAL; -} - -/* - * Get real, policy values from mapped values - */ - -static u16 unmap_class(u16 tclass) -{ - if (tclass < current_mapping_size) - return current_mapping[tclass].value; - - return tclass; -} - -/* - * Get kernel value for class from its policy value - */ -static u16 map_class(u16 pol_value) -{ - u16 i; - - for (i = 1; i < current_mapping_size; i++) { - if (current_mapping[i].value == pol_value) - return i; - } - - return SECCLASS_NULL; -} - -static void map_decision(u16 tclass, struct av_decision *avd, - int allow_unknown) -{ - if (tclass < current_mapping_size) { - unsigned i, n = current_mapping[tclass].num_perms; - u32 result; - - for (i = 0, result = 0; i < n; i++) { - if (avd->allowed & current_mapping[tclass].perms[i]) - result |= 1<<i; - if (allow_unknown && !current_mapping[tclass].perms[i]) - result |= 1<<i; - } - avd->allowed = result; - - for (i = 0, result = 0; i < n; i++) - if (avd->auditallow & current_mapping[tclass].perms[i]) - result |= 1<<i; - avd->auditallow = result; - - for (i = 0, result = 0; i < n; i++) { - if (avd->auditdeny & current_mapping[tclass].perms[i]) - result |= 1<<i; - if (!allow_unknown && !current_mapping[tclass].perms[i]) - result |= 1<<i; - } - /* - * In case the kernel has a bug and requests a permission - * between num_perms and the maximum permission number, we - * should audit that denial - */ - for (; i < (sizeof(u32)*8); i++) - result |= 1<<i; - avd->auditdeny = result; - } -} - -int security_mls_enabled(void) -{ - return policydb.mls_enabled; -} - -/* - * 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]; -} - -/* - * security_dump_masked_av - dumps masked permissions during - * security_compute_av due to RBAC, MLS/Constraint and Type bounds. - */ -static int dump_masked_av_helper(void *k, void *d, void *args) -{ - struct perm_datum *pdatum = d; - char **permission_names = args; - - BUG_ON(pdatum->value < 1 || pdatum->value > 32); - - permission_names[pdatum->value - 1] = (char *)k; - - return 0; -} - -static void security_dump_masked_av(struct context *scontext, - struct context *tcontext, - u16 tclass, - u32 permissions, - const char *reason) -{ - struct common_datum *common_dat; - struct class_datum *tclass_dat; - struct audit_buffer *ab; - char *tclass_name; - char *scontext_name = NULL; - char *tcontext_name = NULL; - char *permission_names[32]; - int index; - u32 length; - bool need_comma = false; - - if (!permissions) - return; - - tclass_name = sym_name(&policydb, SYM_CLASSES, tclass - 1); - tclass_dat = policydb.class_val_to_struct[tclass - 1]; - common_dat = tclass_dat->comdatum; - - /* init permission_names */ - if (common_dat && - hashtab_map(common_dat->permissions.table, - dump_masked_av_helper, permission_names) < 0) - goto out; - - if (hashtab_map(tclass_dat->permissions.table, - dump_masked_av_helper, permission_names) < 0) - goto out; - - /* get scontext/tcontext in text form */ - if (context_struct_to_string(scontext, - &scontext_name, &length) < 0) - goto out; - - if (context_struct_to_string(tcontext, - &tcontext_name, &length) < 0) - goto out; - - /* audit a message */ - ab = audit_log_start(current->audit_context, - GFP_ATOMIC, AUDIT_SELINUX_ERR); - if (!ab) - goto out; - - audit_log_format(ab, "op=security_compute_av reason=%s " - "scontext=%s tcontext=%s tclass=%s perms=", - reason, scontext_name, tcontext_name, tclass_name); - - for (index = 0; index < 32; index++) { - u32 mask = (1 << index); - - if ((mask & permissions) == 0) - continue; - - audit_log_format(ab, "%s%s", - need_comma ? "," : "", - permission_names[index] - ? permission_names[index] : "????"); - need_comma = true; - } - audit_log_end(ab); -out: - /* release scontext/tcontext */ - kfree(tcontext_name); - kfree(scontext_name); - - return; -} - -/* - * security_boundary_permission - drops violated permissions - * on boundary constraint. - */ -static void type_attribute_bounds_av(struct context *scontext, - struct context *tcontext, - u16 tclass, - struct av_decision *avd) -{ - struct context lo_scontext; - struct context lo_tcontext; - struct av_decision lo_avd; - struct type_datum *source; - struct type_datum *target; - u32 masked = 0; - - source = flex_array_get_ptr(policydb.type_val_to_struct_array, - scontext->type - 1); - BUG_ON(!source); - - target = flex_array_get_ptr(policydb.type_val_to_struct_array, - tcontext->type - 1); - BUG_ON(!target); - - if (source->bounds) { - memset(&lo_avd, 0, sizeof(lo_avd)); - - memcpy(&lo_scontext, scontext, sizeof(lo_scontext)); - lo_scontext.type = source->bounds; - - context_struct_compute_av(&lo_scontext, - tcontext, - tclass, - &lo_avd); - if ((lo_avd.allowed & avd->allowed) == avd->allowed) - return; /* no masked permission */ - masked = ~lo_avd.allowed & avd->allowed; - } - - if (target->bounds) { - memset(&lo_avd, 0, sizeof(lo_avd)); - - memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext)); - lo_tcontext.type = target->bounds; - - context_struct_compute_av(scontext, - &lo_tcontext, - tclass, - &lo_avd); - if ((lo_avd.allowed & avd->allowed) == avd->allowed) - return; /* no masked permission */ - masked = ~lo_avd.allowed & avd->allowed; - } - - if (source->bounds && target->bounds) { - memset(&lo_avd, 0, sizeof(lo_avd)); - /* - * lo_scontext and lo_tcontext are already - * set up. - */ - - context_struct_compute_av(&lo_scontext, - &lo_tcontext, - tclass, - &lo_avd); - if ((lo_avd.allowed & avd->allowed) == avd->allowed) - return; /* no masked permission */ - masked = ~lo_avd.allowed & avd->allowed; - } - - if (masked) { - /* mask violated permissions */ - avd->allowed &= ~masked; - - /* audit masked permissions */ - security_dump_masked_av(scontext, tcontext, - tclass, masked, "bounds"); - } -} - -/* - * Compute access vectors based on a context structure pair for - * the permissions in a particular class. - */ -static void context_struct_compute_av(struct context *scontext, - struct context *tcontext, - u16 tclass, - 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; - - avd->allowed = 0; - avd->auditallow = 0; - avd->auditdeny = 0xffffffff; - - if (unlikely(!tclass || tclass > policydb.p_classes.nprim)) { - if (printk_ratelimit()) - printk(KERN_WARNING "SELinux: Invalid class %hu\n", tclass); - return; - } - - tclass_datum = policydb.class_val_to_struct[tclass - 1]; - - /* - * If a specific type enforcement rule was defined for - * this permission check, then use it. - */ - avkey.target_class = tclass; - avkey.specified = AVTAB_AV; - sattr = flex_array_get(policydb.type_attr_map_array, scontext->type - 1); - BUG_ON(!sattr); - tattr = flex_array_get(policydb.type_attr_map_array, tcontext->type - 1); - BUG_ON(!tattr); - ebitmap_for_each_positive_bit(sattr, snode, i) { - ebitmap_for_each_positive_bit(tattr, tnode, j) { - avkey.source_type = i + 1; - avkey.target_type = j + 1; - for (node = avtab_search_node(&policydb.te_avtab, &avkey); - node; - 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 &= ~(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 == policydb.process_class && - (avd->allowed & policydb.process_trans_perms) && - 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 &= ~policydb.process_trans_perms; - } - - /* - * If the given source and target types have boundary - * constraint, lazy checks have to mask any violated - * permission and notice it to userspace via audit. - */ - type_attribute_bounds_av(scontext, tcontext, - tclass, avd); -} - -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)) - goto out; - if (context_struct_to_string(ncontext, &n, &nlen)) - goto out; - if (context_struct_to_string(tcontext, &t, &tlen)) - 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, sym_name(&policydb, SYM_CLASSES, 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 orig_tclass) -{ - struct context *ocontext; - struct context *ncontext; - struct context *tcontext; - struct class_datum *tclass_datum; - struct constraint_node *constraint; - u16 tclass; - int rc = 0; - - if (!ss_initialized) - return 0; - - read_lock(&policy_rwlock); - - tclass = unmap_class(orig_tclass); - - if (!tclass || tclass > policydb.p_classes.nprim) { - printk(KERN_ERR "SELinux: %s: unrecognized class %d\n", - __func__, tclass); - rc = -EINVAL; - goto out; - } - tclass_datum = policydb.class_val_to_struct[tclass - 1]; - - ocontext = sidtab_search(&sidtab, oldsid); - if (!ocontext) { - printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", - __func__, oldsid); - rc = -EINVAL; - goto out; - } - - ncontext = sidtab_search(&sidtab, newsid); - if (!ncontext) { - printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", - __func__, newsid); - rc = -EINVAL; - goto out; - } - - tcontext = sidtab_search(&sidtab, tasksid); - if (!tcontext) { - printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", - __func__, 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: - read_unlock(&policy_rwlock); - return rc; -} - -/* - * security_bounded_transition - check whether the given - * transition is directed to bounded, or not. - * It returns 0, if @newsid is bounded by @oldsid. - * Otherwise, it returns error code. - * - * @oldsid : current security identifier - * @newsid : destinated security identifier - */ -int security_bounded_transition(u32 old_sid, u32 new_sid) -{ - struct context *old_context, *new_context; - struct type_datum *type; - int index; - int rc; - - read_lock(&policy_rwlock); - - rc = -EINVAL; - old_context = sidtab_search(&sidtab, old_sid); - if (!old_context) { - printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n", - __func__, old_sid); - goto out; - } - - rc = -EINVAL; - new_context = sidtab_search(&sidtab, new_sid); - if (!new_context) { - printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n", - __func__, new_sid); - goto out; - } - - rc = 0; - /* type/domain unchanged */ - if (old_context->type == new_context->type) - goto out; - - index = new_context->type; - while (true) { - type = flex_array_get_ptr(policydb.type_val_to_struct_array, - index - 1); - BUG_ON(!type); - - /* not bounded anymore */ - rc = -EPERM; - if (!type->bounds) - break; - - /* @newsid is bounded by @oldsid */ - rc = 0; - if (type->bounds == old_context->type) - break; - - index = type->bounds; - } - - if (rc) { - char *old_name = NULL; - char *new_name = NULL; - u32 length; - - if (!context_struct_to_string(old_context, - &old_name, &length) && - !context_struct_to_string(new_context, - &new_name, &length)) { - audit_log(current->audit_context, - GFP_ATOMIC, AUDIT_SELINUX_ERR, - "op=security_bounded_transition " - "result=denied " - "oldcontext=%s newcontext=%s", - old_name, new_name); - } - kfree(new_name); - kfree(old_name); - } -out: - read_unlock(&policy_rwlock); - - return rc; -} - -static void avd_init(struct av_decision *avd) -{ - avd->allowed = 0; - avd->auditallow = 0; - avd->auditdeny = 0xffffffff; - avd->seqno = latest_granting; - avd->flags = 0; -} - - -/** - * security_compute_av - Compute access vector decisions. - * @ssid: source security identifier - * @tsid: target security identifier - * @tclass: target security class - * @avd: access vector decisions - * - * Compute a set of access vector decisions based on the - * SID pair (@ssid, @tsid) for the permissions in @tclass. - */ -void security_compute_av(u32 ssid, - u32 tsid, - u16 orig_tclass, - struct av_decision *avd) -{ - u16 tclass; - struct context *scontext = NULL, *tcontext = NULL; - - read_lock(&policy_rwlock); - avd_init(avd); - if (!ss_initialized) - goto allow; - - scontext = sidtab_search(&sidtab, ssid); - if (!scontext) { - printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", - __func__, ssid); - goto out; - } - - /* permissive domain? */ - if (ebitmap_get_bit(&policydb.permissive_map, scontext->type)) - avd->flags |= AVD_FLAGS_PERMISSIVE; - - tcontext = sidtab_search(&sidtab, tsid); - if (!tcontext) { - printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", - __func__, tsid); - goto out; - } - - tclass = unmap_class(orig_tclass); - if (unlikely(orig_tclass && !tclass)) { - if (policydb.allow_unknown) - goto allow; - goto out; - } - context_struct_compute_av(scontext, tcontext, tclass, avd); - map_decision(orig_tclass, avd, policydb.allow_unknown); -out: - read_unlock(&policy_rwlock); - return; -allow: - avd->allowed = 0xffffffff; - goto out; -} - -void security_compute_av_user(u32 ssid, - u32 tsid, - u16 tclass, - struct av_decision *avd) -{ - struct context *scontext = NULL, *tcontext = NULL; - - read_lock(&policy_rwlock); - avd_init(avd); - if (!ss_initialized) - goto allow; - - scontext = sidtab_search(&sidtab, ssid); - if (!scontext) { - printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", - __func__, ssid); - goto out; - } - - /* permissive domain? */ - if (ebitmap_get_bit(&policydb.permissive_map, scontext->type)) - avd->flags |= AVD_FLAGS_PERMISSIVE; - - tcontext = sidtab_search(&sidtab, tsid); - if (!tcontext) { - printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", - __func__, tsid); - goto out; - } - - if (unlikely(!tclass)) { - if (policydb.allow_unknown) - goto allow; - goto out; - } - - context_struct_compute_av(scontext, tcontext, tclass, avd); - out: - read_unlock(&policy_rwlock); - return; -allow: - avd->allowed = 0xffffffff; - goto out; -} - -/* - * 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; - - if (scontext) - *scontext = NULL; - *scontext_len = 0; - - if (context->len) { - *scontext_len = context->len; - *scontext = kstrdup(context->str, GFP_ATOMIC); - if (!(*scontext)) - return -ENOMEM; - return 0; - } - - /* Compute the size of the context. */ - *scontext_len += strlen(sym_name(&policydb, SYM_USERS, context->user - 1)) + 1; - *scontext_len += strlen(sym_name(&policydb, SYM_ROLES, context->role - 1)) + 1; - *scontext_len += strlen(sym_name(&policydb, SYM_TYPES, context->type - 1)) + 1; - *scontext_len += mls_compute_context_len(context); - - if (!scontext) - return 0; - - /* 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", - sym_name(&policydb, SYM_USERS, context->user - 1), - sym_name(&policydb, SYM_ROLES, context->role - 1), - sym_name(&policydb, SYM_TYPES, context->type - 1)); - scontextp += strlen(sym_name(&policydb, SYM_USERS, context->user - 1)) + - 1 + strlen(sym_name(&policydb, SYM_ROLES, context->role - 1)) + - 1 + strlen(sym_name(&policydb, SYM_TYPES, context->type - 1)); - - mls_sid_to_context(context, &scontextp); - - *scontextp = 0; - - return 0; -} - -#include "initial_sid_to_string.h" - -const char *security_get_initial_sid_context(u32 sid) -{ - if (unlikely(sid > SECINITSID_NUM)) - return NULL; - return initial_sid_to_string[sid]; -} - -static int security_sid_to_context_core(u32 sid, char **scontext, - u32 *scontext_len, int force) -{ - struct context *context; - int rc = 0; - - if (scontext) - *scontext = NULL; - *scontext_len = 0; - - if (!ss_initialized) { - if (sid <= SECINITSID_NUM) { - char *scontextp; - - *scontext_len = strlen(initial_sid_to_string[sid]) + 1; - if (!scontext) - goto out; - scontextp = kmalloc(*scontext_len, GFP_ATOMIC); - if (!scontextp) { - rc = -ENOMEM; - goto out; - } - strcpy(scontextp, initial_sid_to_string[sid]); - *scontext = scontextp; - goto out; - } - printk(KERN_ERR "SELinux: %s: called before initial " - "load_policy on unknown SID %d\n", __func__, sid); - rc = -EINVAL; - goto out; - } - read_lock(&policy_rwlock); - if (force) - context = sidtab_search_force(&sidtab, sid); - else - context = sidtab_search(&sidtab, sid); - if (!context) { - printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", - __func__, sid); - rc = -EINVAL; - goto out_unlock; - } - rc = context_struct_to_string(context, scontext, scontext_len); -out_unlock: - read_unlock(&policy_rwlock); -out: - return rc; - -} - -/** - * 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) -{ - return security_sid_to_context_core(sid, scontext, scontext_len, 0); -} - -int security_sid_to_context_force(u32 sid, char **scontext, u32 *scontext_len) -{ - return security_sid_to_context_core(sid, scontext, scontext_len, 1); -} - -/* - * Caveat: Mutates scontext. - */ -static int string_to_context_struct(struct policydb *pol, - struct sidtab *sidtabp, - char *scontext, - u32 scontext_len, - struct context *ctx, - u32 def_sid) -{ - struct role_datum *role; - struct type_datum *typdatum; - struct user_datum *usrdatum; - char *scontextp, *p, oldc; - int rc = 0; - - context_init(ctx); - - /* Parse the security context. */ - - rc = -EINVAL; - scontextp = (char *) scontext; - - /* Extract the user. */ - p = scontextp; - while (*p && *p != ':') - p++; - - if (*p == 0) - goto out; - - *p++ = 0; - - usrdatum = hashtab_search(pol->p_users.table, scontextp); - if (!usrdatum) - goto out; - - ctx->user = usrdatum->value; - - /* Extract role. */ - scontextp = p; - while (*p && *p != ':') - p++; - - if (*p == 0) - goto out; - - *p++ = 0; - - role = hashtab_search(pol->p_roles.table, scontextp); - if (!role) - goto out; - ctx->role = role->value; - - /* Extract type. */ - scontextp = p; - while (*p && *p != ':') - p++; - oldc = *p; - *p++ = 0; - - typdatum = hashtab_search(pol->p_types.table, scontextp); - if (!typdatum || typdatum->attribute) - goto out; - - ctx->type = typdatum->value; - - rc = mls_context_to_sid(pol, oldc, &p, ctx, sidtabp, def_sid); - if (rc) - goto out; - - rc = -EINVAL; - if ((p - scontext) < scontext_len) - goto out; - - /* Check the validity of the new context. */ - if (!policydb_context_isvalid(pol, ctx)) - goto out; - rc = 0; -out: - if (rc) - context_destroy(ctx); - return rc; -} - -static int security_context_to_sid_core(const char *scontext, u32 scontext_len, - u32 *sid, u32 def_sid, gfp_t gfp_flags, - int force) -{ - char *scontext2, *str = NULL; - struct context context; - 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; - return 0; - } - } - *sid = SECINITSID_KERNEL; - return 0; - } - *sid = SECSID_NULL; - - /* Copy the string so that we can modify the copy as we parse it. */ - scontext2 = kmalloc(scontext_len + 1, gfp_flags); - if (!scontext2) - return -ENOMEM; - memcpy(scontext2, scontext, scontext_len); - scontext2[scontext_len] = 0; - - if (force) { - /* Save another copy for storing in uninterpreted form */ - rc = -ENOMEM; - str = kstrdup(scontext2, gfp_flags); - if (!str) - goto out; - } - - read_lock(&policy_rwlock); - rc = string_to_context_struct(&policydb, &sidtab, scontext2, - scontext_len, &context, def_sid); - if (rc == -EINVAL && force) { - context.str = str; - context.len = scontext_len; - str = NULL; - } else if (rc) - goto out_unlock; - rc = sidtab_context_to_sid(&sidtab, &context, sid); - context_destroy(&context); -out_unlock: - read_unlock(&policy_rwlock); -out: - kfree(scontext2); - kfree(str); - 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(const char *scontext, u32 scontext_len, u32 *sid) -{ - return security_context_to_sid_core(scontext, scontext_len, - sid, SECSID_NULL, GFP_KERNEL, 0); -} - -/** - * 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 error - * - * 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). - * Implicitly forces adding of the context even if it cannot be mapped yet. - * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient - * memory is available, or 0 on success. - */ -int security_context_to_sid_default(const char *scontext, u32 scontext_len, - u32 *sid, u32 def_sid, gfp_t gfp_flags) -{ - return security_context_to_sid_core(scontext, scontext_len, - sid, def_sid, gfp_flags, 1); -} - -int security_context_to_sid_force(const char *scontext, u32 scontext_len, - u32 *sid) -{ - return security_context_to_sid_core(scontext, scontext_len, - sid, SECSID_NULL, GFP_KERNEL, 1); -} - -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)) - goto out; - if (context_struct_to_string(tcontext, &t, &tlen)) - goto out; - if (context_struct_to_string(newcontext, &n, &nlen)) - 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, sym_name(&policydb, SYM_CLASSES, tclass-1)); -out: - kfree(s); - kfree(t); - kfree(n); - if (!selinux_enforcing) - return 0; - return -EACCES; -} - -static void filename_compute_type(struct policydb *p, struct context *newcontext, - u32 stype, u32 ttype, u16 tclass, - const char *objname) -{ - struct filename_trans ft; - struct filename_trans_datum *otype; - - /* - * Most filename trans rules are going to live in specific directories - * like /dev or /var/run. This bitmap will quickly skip rule searches - * if the ttype does not contain any rules. - */ - if (!ebitmap_get_bit(&p->filename_trans_ttypes, ttype)) - return; - - ft.stype = stype; - ft.ttype = ttype; - ft.tclass = tclass; - ft.name = objname; - - otype = hashtab_search(p->filename_trans, &ft); - if (otype) - newcontext->type = otype->otype; -} - -static int security_compute_sid(u32 ssid, - u32 tsid, - u16 orig_tclass, - u32 specified, - const char *objname, - u32 *out_sid, - bool kern) -{ - struct context *scontext = NULL, *tcontext = NULL, newcontext; - struct role_trans *roletr = NULL; - struct avtab_key avkey; - struct avtab_datum *avdatum; - struct avtab_node *node; - u16 tclass; - int rc = 0; - bool sock; - - if (!ss_initialized) { - switch (orig_tclass) { - case SECCLASS_PROCESS: /* kernel value */ - *out_sid = ssid; - break; - default: - *out_sid = tsid; - break; - } - goto out; - } - - context_init(&newcontext); - - read_lock(&policy_rwlock); - - if (kern) { - tclass = unmap_class(orig_tclass); - sock = security_is_socket_class(orig_tclass); - } else { - tclass = orig_tclass; - sock = security_is_socket_class(map_class(tclass)); - } - - scontext = sidtab_search(&sidtab, ssid); - if (!scontext) { - printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", - __func__, ssid); - rc = -EINVAL; - goto out_unlock; - } - tcontext = sidtab_search(&sidtab, tsid); - if (!tcontext) { - printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", - __func__, tsid); - rc = -EINVAL; - goto out_unlock; - } - - /* 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. */ - if ((tclass == policydb.process_class) || (sock == true)) { - /* Use the current role and type of process. */ - newcontext.role = scontext->role; - newcontext.type = scontext->type; - } else { - /* 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; 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; - } - - /* if we have a objname this is a file trans check so check those rules */ - if (objname) - filename_compute_type(&policydb, &newcontext, scontext->type, - tcontext->type, tclass, objname); - - /* Check for class-specific changes. */ - 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) && - (roletr->tclass == tclass)) { - /* Use the role transition rule. */ - newcontext.role = roletr->new_role; - break; - } - } - } - - /* Set the MLS attributes. - This is done last because it may allocate memory. */ - rc = mls_compute_sid(scontext, tcontext, tclass, specified, - &newcontext, sock); - 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: - read_unlock(&policy_rwlock); - 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, - const struct qstr *qstr, u32 *out_sid) -{ - return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, - qstr ? qstr->name : NULL, out_sid, true); -} - -int security_transition_sid_user(u32 ssid, u32 tsid, u16 tclass, - const char *objname, u32 *out_sid) -{ - return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, - objname, out_sid, false); -} - -/** - * 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, NULL, - out_sid, false); -} - -/** - * 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, NULL, - out_sid, false); -} - -/* Clone the SID into the new SID table. */ -static int clone_sid(u32 sid, - struct context *context, - void *arg) -{ - struct sidtab *s = arg; - - if (sid > SECINITSID_NUM) - return sidtab_insert(s, sid, context); - else - return 0; -} - -static inline int convert_context_handle_invalid_context(struct context *context) -{ - char *s; - u32 len; - - if (selinux_enforcing) - return -EINVAL; - - if (!context_struct_to_string(context, &s, &len)) { - printk(KERN_WARNING "SELinux: Context %s would be invalid if enforcing\n", s); - kfree(s); - } - return 0; -} - -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 ocontext *oc; - struct mls_range *range; - struct role_datum *role; - struct type_datum *typdatum; - struct user_datum *usrdatum; - char *s; - u32 len; - int rc = 0; - - if (key <= SECINITSID_NUM) - goto out; - - args = p; - - if (c->str) { - struct context ctx; - - rc = -ENOMEM; - s = kstrdup(c->str, GFP_KERNEL); - if (!s) - goto out; - - rc = string_to_context_struct(args->newp, NULL, s, - c->len, &ctx, SECSID_NULL); - kfree(s); - if (!rc) { - printk(KERN_INFO "SELinux: Context %s became valid (mapped).\n", - c->str); - /* Replace string with mapped representation. */ - kfree(c->str); - memcpy(c, &ctx, sizeof(*c)); - goto out; - } else if (rc == -EINVAL) { - /* Retain string representation for later mapping. */ - rc = 0; - goto out; - } else { - /* Other error condition, e.g. ENOMEM. */ - printk(KERN_ERR "SELinux: Unable to map context %s, rc = %d.\n", - c->str, -rc); - goto out; - } - } - - rc = context_cpy(&oldc, c); - if (rc) - goto out; - - /* Convert the user. */ - rc = -EINVAL; - usrdatum = hashtab_search(args->newp->p_users.table, - sym_name(args->oldp, SYM_USERS, c->user - 1)); - if (!usrdatum) - goto bad; - c->user = usrdatum->value; - - /* Convert the role. */ - rc = -EINVAL; - role = hashtab_search(args->newp->p_roles.table, - sym_name(args->oldp, SYM_ROLES, c->role - 1)); - if (!role) - goto bad; - c->role = role->value; - - /* Convert the type. */ - rc = -EINVAL; - typdatum = hashtab_search(args->newp->p_types.table, - sym_name(args->oldp, SYM_TYPES, c->type - 1)); - if (!typdatum) - goto bad; - c->type = typdatum->value; - - /* Convert the MLS fields if dealing with MLS policies */ - if (args->oldp->mls_enabled && args->newp->mls_enabled) { - rc = mls_convert_context(args->oldp, args->newp, c); - if (rc) - goto bad; - } else if (args->oldp->mls_enabled && !args->newp->mls_enabled) { - /* - * Switching between MLS and non-MLS policy: - * free any storage used by the MLS fields in the - * context for all existing entries in the sidtab. - */ - mls_context_destroy(c); - } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) { - /* - * Switching between non-MLS and MLS policy: - * ensure that the MLS fields of the context for all - * existing entries in the sidtab are filled in with a - * suitable default value, likely taken from one of the - * initial SIDs. - */ - oc = args->newp->ocontexts[OCON_ISID]; - while (oc && oc->sid[0] != SECINITSID_UNLABELED) - oc = oc->next; - rc = -EINVAL; - if (!oc) { - printk(KERN_ERR "SELinux: unable to look up" - " the initial SIDs list\n"); - goto bad; - } - range = &oc->context[0].range; - rc = mls_range_set(c, range); - 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); - - rc = 0; -out: - return rc; -bad: - /* Map old representation to string and save it. */ - rc = context_struct_to_string(&oldc, &s, &len); - if (rc) - return rc; - context_destroy(&oldc); - context_destroy(c); - c->str = s; - c->len = len; - printk(KERN_INFO "SELinux: Context %s became invalid (unmapped).\n", - c->str); - rc = 0; - goto out; -} - -static void security_load_policycaps(void) -{ - selinux_policycap_netpeer = ebitmap_get_bit(&policydb.policycaps, - POLICYDB_CAPABILITY_NETPEER); - selinux_policycap_openperm = ebitmap_get_bit(&policydb.policycaps, - POLICYDB_CAPABILITY_OPENPERM); -} - -static int security_preserve_bools(struct policydb *p); - -/** - * 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 selinux_mapping *oldmap, *map = NULL; - struct convert_context_args args; - u32 seqno; - u16 map_size; - int rc = 0; - struct policy_file file = { data, len }, *fp = &file; - - if (!ss_initialized) { - avtab_cache_init(); - rc = policydb_read(&policydb, fp); - if (rc) { - avtab_cache_destroy(); - return rc; - } - - policydb.len = len; - rc = selinux_set_mapping(&policydb, secclass_map, - ¤t_mapping, - ¤t_mapping_size); - if (rc) { - policydb_destroy(&policydb); - avtab_cache_destroy(); - return rc; - } - - rc = policydb_load_isids(&policydb, &sidtab); - if (rc) { - policydb_destroy(&policydb); - avtab_cache_destroy(); - return rc; - } - - security_load_policycaps(); - ss_initialized = 1; - seqno = ++latest_granting; - selinux_complete_init(); - avc_ss_reset(seqno); - selnl_notify_policyload(seqno); - selinux_status_update_policyload(seqno); - selinux_netlbl_cache_invalidate(); - selinux_xfrm_notify_policyload(); - return 0; - } - -#if 0 - sidtab_hash_eval(&sidtab, "sids"); -#endif - - rc = policydb_read(&newpolicydb, fp); - if (rc) - return rc; - - newpolicydb.len = len; - /* If switching between different policy types, log MLS status */ - if (policydb.mls_enabled && !newpolicydb.mls_enabled) - printk(KERN_INFO "SELinux: Disabling MLS support...\n"); - else if (!policydb.mls_enabled && newpolicydb.mls_enabled) - printk(KERN_INFO "SELinux: Enabling MLS support...\n"); - - rc = policydb_load_isids(&newpolicydb, &newsidtab); - if (rc) { - printk(KERN_ERR "SELinux: unable to load the initial SIDs\n"); - policydb_destroy(&newpolicydb); - return rc; - } - - rc = selinux_set_mapping(&newpolicydb, secclass_map, &map, &map_size); - if (rc) - goto err; - - rc = security_preserve_bools(&newpolicydb); - if (rc) { - printk(KERN_ERR "SELinux: unable to preserve booleans\n"); - goto err; - } - - /* Clone the SID table. */ - sidtab_shutdown(&sidtab); - - rc = sidtab_map(&sidtab, clone_sid, &newsidtab); - if (rc) - goto err; - - /* - * Convert the internal representations of contexts - * in the new SID table. - */ - args.oldp = &policydb; - args.newp = &newpolicydb; - rc = sidtab_map(&newsidtab, convert_context, &args); - if (rc) { - printk(KERN_ERR "SELinux: unable to convert the internal" - " representation of contexts in the new SID" - " table\n"); - goto err; - } - - /* 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. */ - write_lock_irq(&policy_rwlock); - memcpy(&policydb, &newpolicydb, sizeof policydb); - sidtab_set(&sidtab, &newsidtab); - security_load_policycaps(); - oldmap = current_mapping; - current_mapping = map; - current_mapping_size = map_size; - seqno = ++latest_granting; - write_unlock_irq(&policy_rwlock); - - /* Free the old policydb and SID table. */ - policydb_destroy(&oldpolicydb); - sidtab_destroy(&oldsidtab); - kfree(oldmap); - - avc_ss_reset(seqno); - selnl_notify_policyload(seqno); - selinux_status_update_policyload(seqno); - selinux_netlbl_cache_invalidate(); - selinux_xfrm_notify_policyload(); - - return 0; - -err: - kfree(map); - sidtab_destroy(&newsidtab); - policydb_destroy(&newpolicydb); - return rc; - -} - -size_t security_policydb_len(void) -{ - size_t len; - - read_lock(&policy_rwlock); - len = policydb.len; - read_unlock(&policy_rwlock); - - return len; -} - -/** - * security_port_sid - Obtain the SID for a port. - * @protocol: protocol number - * @port: port number - * @out_sid: security identifier - */ -int security_port_sid(u8 protocol, u16 port, u32 *out_sid) -{ - struct ocontext *c; - int rc = 0; - - read_lock(&policy_rwlock); - - 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: - read_unlock(&policy_rwlock); - return rc; -} - -/** - * security_netif_sid - Obtain the SID for a network interface. - * @name: interface name - * @if_sid: interface SID - */ -int security_netif_sid(char *name, u32 *if_sid) -{ - int rc = 0; - struct ocontext *c; - - read_lock(&policy_rwlock); - - 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]; - } else - *if_sid = SECINITSID_NETIF; - -out: - read_unlock(&policy_rwlock); - 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; - struct ocontext *c; - - read_lock(&policy_rwlock); - - switch (domain) { - case AF_INET: { - u32 addr; - - rc = -EINVAL; - if (addrlen != sizeof(u32)) - 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: - rc = -EINVAL; - if (addrlen != sizeof(u64) * 2) - 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: - rc = 0; - *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; - } - - rc = 0; -out: - read_unlock(&policy_rwlock); - 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 = NULL, *mysids2, sid; - u32 mynel = 0, maxnel = SIDS_NEL; - struct user_datum *user; - struct role_datum *role; - struct ebitmap_node *rnode, *tnode; - int rc = 0, i, j; - - *sids = NULL; - *nel = 0; - - if (!ss_initialized) - goto out; - - read_lock(&policy_rwlock); - - context_init(&usercon); - - rc = -EINVAL; - fromcon = sidtab_search(&sidtab, fromsid); - if (!fromcon) - goto out_unlock; - - rc = -EINVAL; - user = hashtab_search(policydb.p_users.table, username); - if (!user) - goto out_unlock; - - usercon.user = user->value; - - rc = -ENOMEM; - mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC); - if (!mysids) - goto out_unlock; - - ebitmap_for_each_positive_bit(&user->roles, rnode, i) { - role = policydb.role_val_to_struct[i]; - usercon.role = i + 1; - ebitmap_for_each_positive_bit(&role->types, tnode, j) { - usercon.type = j + 1; - - if (mls_setup_user_range(fromcon, user, &usercon)) - continue; - - rc = sidtab_context_to_sid(&sidtab, &usercon, &sid); - if (rc) - goto out_unlock; - if (mynel < maxnel) { - mysids[mynel++] = sid; - } else { - rc = -ENOMEM; - maxnel += SIDS_NEL; - mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC); - if (!mysids2) - goto out_unlock; - memcpy(mysids2, mysids, mynel * sizeof(*mysids2)); - kfree(mysids); - mysids = mysids2; - mysids[mynel++] = sid; - } - } - } - rc = 0; -out_unlock: - read_unlock(&policy_rwlock); - if (rc || !mynel) { - kfree(mysids); - goto out; - } - - rc = -ENOMEM; - mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL); - if (!mysids2) { - kfree(mysids); - goto out; - } - for (i = 0, j = 0; i < mynel; i++) { - struct av_decision dummy_avd; - rc = avc_has_perm_noaudit(fromsid, mysids[i], - SECCLASS_PROCESS, /* kernel value */ - PROCESS__TRANSITION, AVC_STRICT, - &dummy_avd); - if (!rc) - mysids2[j++] = mysids[i]; - cond_resched(); - } - rc = 0; - kfree(mysids); - *sids = mysids2; - *nel = j; -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 orig_sclass, - u32 *sid) -{ - int len; - u16 sclass; - struct genfs *genfs; - struct ocontext *c; - int rc, cmp = 0; - - while (path[0] == '/' && path[1] == '/') - path++; - - read_lock(&policy_rwlock); - - sclass = unmap_class(orig_sclass); - *sid = SECINITSID_UNLABELED; - - for (genfs = policydb.genfs; genfs; genfs = genfs->next) { - cmp = strcmp(fstype, genfs->fstype); - if (cmp <= 0) - break; - } - - rc = -ENOENT; - if (!genfs || cmp) - 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; - } - - rc = -ENOENT; - if (!c) - 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]; - rc = 0; -out: - read_unlock(&policy_rwlock); - 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; - - read_lock(&policy_rwlock); - - 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: - read_unlock(&policy_rwlock); - return rc; -} - -int security_get_bools(int *len, char ***names, int **values) -{ - int i, rc; - - read_lock(&policy_rwlock); - *names = NULL; - *values = NULL; - - rc = 0; - *len = policydb.p_bools.nprim; - if (!*len) - goto out; - - rc = -ENOMEM; - *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC); - if (!*names) - goto err; - - rc = -ENOMEM; - *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(sym_name(&policydb, SYM_BOOLS, i)) + 1; - - rc = -ENOMEM; - (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC); - if (!(*names)[i]) - goto err; - - strncpy((*names)[i], sym_name(&policydb, SYM_BOOLS, i), name_len); - (*names)[i][name_len - 1] = 0; - } - rc = 0; -out: - read_unlock(&policy_rwlock); - 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; - int lenp, seqno = 0; - struct cond_node *cur; - - write_lock_irq(&policy_rwlock); - - rc = -EFAULT; - lenp = policydb.p_bools.nprim; - if (len != lenp) - 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 ses=%u", - sym_name(&policydb, SYM_BOOLS, i), - !!values[i], - policydb.bool_val_to_struct[i]->state, - audit_get_loginuid(current), - audit_get_sessionid(current)); - } - 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; cur = cur->next) { - rc = evaluate_cond_node(&policydb, cur); - if (rc) - goto out; - } - - seqno = ++latest_granting; - rc = 0; -out: - write_unlock_irq(&policy_rwlock); - if (!rc) { - avc_ss_reset(seqno); - selnl_notify_policyload(seqno); - selinux_status_update_policyload(seqno); - selinux_xfrm_notify_policyload(); - } - return rc; -} - -int security_get_bool_value(int bool) -{ - int rc; - int len; - - read_lock(&policy_rwlock); - - rc = -EFAULT; - len = policydb.p_bools.nprim; - if (bool >= len) - goto out; - - rc = policydb.bool_val_to_struct[bool]->state; -out: - read_unlock(&policy_rwlock); - return rc; -} - -static int security_preserve_bools(struct policydb *p) -{ - int rc, nbools = 0, *bvalues = NULL, i; - char **bnames = NULL; - struct cond_bool_datum *booldatum; - struct cond_node *cur; - - rc = security_get_bools(&nbools, &bnames, &bvalues); - if (rc) - goto out; - for (i = 0; i < nbools; i++) { - booldatum = hashtab_search(p->p_bools.table, bnames[i]); - if (booldatum) - booldatum->state = bvalues[i]; - } - for (cur = p->cond_list; cur; cur = cur->next) { - rc = evaluate_cond_node(p, cur); - if (rc) - goto out; - } - -out: - if (bnames) { - for (i = 0; i < nbools; i++) - kfree(bnames[i]); - } - kfree(bnames); - kfree(bvalues); - return rc; -} - -/* - * security_sid_mls_copy() - computes a new sid based on the given - * sid and the mls portion of mls_sid. - */ -int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid) -{ - struct context *context1; - struct context *context2; - struct context newcon; - char *s; - u32 len; - int rc; - - rc = 0; - if (!ss_initialized || !policydb.mls_enabled) { - *new_sid = sid; - goto out; - } - - context_init(&newcon); - - read_lock(&policy_rwlock); - - rc = -EINVAL; - context1 = sidtab_search(&sidtab, sid); - if (!context1) { - printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", - __func__, sid); - goto out_unlock; - } - - rc = -EINVAL; - context2 = sidtab_search(&sidtab, mls_sid); - if (!context2) { - printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", - __func__, mls_sid); - goto out_unlock; - } - - newcon.user = context1->user; - newcon.role = context1->role; - newcon.type = context1->type; - rc = mls_context_cpy(&newcon, context2); - if (rc) - goto out_unlock; - - /* Check the validity of the new context. */ - if (!policydb_context_isvalid(&policydb, &newcon)) { - rc = convert_context_handle_invalid_context(&newcon); - if (rc) { - if (!context_struct_to_string(&newcon, &s, &len)) { - audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR, - "security_sid_mls_copy: invalid context %s", s); - kfree(s); - } - goto out_unlock; - } - } - - rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid); -out_unlock: - read_unlock(&policy_rwlock); - context_destroy(&newcon); -out: - return rc; -} - -/** - * security_net_peersid_resolve - Compare and resolve two network peer SIDs - * @nlbl_sid: NetLabel SID - * @nlbl_type: NetLabel labeling protocol type - * @xfrm_sid: XFRM SID - * - * Description: - * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be - * resolved into a single SID it is returned via @peer_sid and the function - * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function - * returns a negative value. A table summarizing the behavior is below: - * - * | function return | @sid - * ------------------------------+-----------------+----------------- - * no peer labels | 0 | SECSID_NULL - * single peer label | 0 | <peer_label> - * multiple, consistent labels | 0 | <peer_label> - * multiple, inconsistent labels | -<errno> | SECSID_NULL - * - */ -int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type, - u32 xfrm_sid, - u32 *peer_sid) -{ - int rc; - struct context *nlbl_ctx; - struct context *xfrm_ctx; - - *peer_sid = SECSID_NULL; - - /* handle the common (which also happens to be the set of easy) cases - * right away, these two if statements catch everything involving a - * single or absent peer SID/label */ - if (xfrm_sid == SECSID_NULL) { - *peer_sid = nlbl_sid; - return 0; - } - /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label - * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label - * is present */ - if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) { - *peer_sid = xfrm_sid; - return 0; - } - - /* we don't need to check ss_initialized here since the only way both - * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the - * security server was initialized and ss_initialized was true */ - if (!policydb.mls_enabled) - return 0; - - read_lock(&policy_rwlock); - - rc = -EINVAL; - nlbl_ctx = sidtab_search(&sidtab, nlbl_sid); - if (!nlbl_ctx) { - printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", - __func__, nlbl_sid); - goto out; - } - rc = -EINVAL; - xfrm_ctx = sidtab_search(&sidtab, xfrm_sid); - if (!xfrm_ctx) { - printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", - __func__, xfrm_sid); - goto out; - } - rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES); - if (rc) - goto out; - - /* at present NetLabel SIDs/labels really only carry MLS - * information so if the MLS portion of the NetLabel SID - * matches the MLS portion of the labeled XFRM SID/label - * then pass along the XFRM SID as it is the most - * expressive */ - *peer_sid = xfrm_sid; -out: - read_unlock(&policy_rwlock); - return rc; -} - -static int get_classes_callback(void *k, void *d, void *args) -{ - struct class_datum *datum = d; - char *name = k, **classes = args; - int value = datum->value - 1; - - classes[value] = kstrdup(name, GFP_ATOMIC); - if (!classes[value]) - return -ENOMEM; - - return 0; -} - -int security_get_classes(char ***classes, int *nclasses) -{ - int rc; - - read_lock(&policy_rwlock); - - rc = -ENOMEM; - *nclasses = policydb.p_classes.nprim; - *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC); - if (!*classes) - goto out; - - rc = hashtab_map(policydb.p_classes.table, get_classes_callback, - *classes); - if (rc) { - int i; - for (i = 0; i < *nclasses; i++) - kfree((*classes)[i]); - kfree(*classes); - } - -out: - read_unlock(&policy_rwlock); - return rc; -} - -static int get_permissions_callback(void *k, void *d, void *args) -{ - struct perm_datum *datum = d; - char *name = k, **perms = args; - int value = datum->value - 1; - - perms[value] = kstrdup(name, GFP_ATOMIC); - if (!perms[value]) - return -ENOMEM; - - return 0; -} - -int security_get_permissions(char *class, char ***perms, int *nperms) -{ - int rc, i; - struct class_datum *match; - - read_lock(&policy_rwlock); - - rc = -EINVAL; - match = hashtab_search(policydb.p_classes.table, class); - if (!match) { - printk(KERN_ERR "SELinux: %s: unrecognized class %s\n", - __func__, class); - goto out; - } - - rc = -ENOMEM; - *nperms = match->permissions.nprim; - *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC); - if (!*perms) - goto out; - - if (match->comdatum) { - rc = hashtab_map(match->comdatum->permissions.table, - get_permissions_callback, *perms); - if (rc) - goto err; - } - - rc = hashtab_map(match->permissions.table, get_permissions_callback, - *perms); - if (rc) - goto err; - -out: - read_unlock(&policy_rwlock); - return rc; - -err: - read_unlock(&policy_rwlock); - for (i = 0; i < *nperms; i++) - kfree((*perms)[i]); - kfree(*perms); - return rc; -} - -int security_get_reject_unknown(void) -{ - return policydb.reject_unknown; -} - -int security_get_allow_unknown(void) -{ - return policydb.allow_unknown; -} - -/** - * security_policycap_supported - Check for a specific policy capability - * @req_cap: capability - * - * Description: - * This function queries the currently loaded policy to see if it supports the - * capability specified by @req_cap. Returns true (1) if the capability is - * supported, false (0) if it isn't supported. - * - */ -int security_policycap_supported(unsigned int req_cap) -{ - int rc; - - read_lock(&policy_rwlock); - rc = ebitmap_get_bit(&policydb.policycaps, req_cap); - read_unlock(&policy_rwlock); - - return rc; -} - -struct selinux_audit_rule { - u32 au_seqno; - struct context au_ctxt; -}; - -void selinux_audit_rule_free(void *vrule) -{ - struct selinux_audit_rule *rule = vrule; - - if (rule) { - context_destroy(&rule->au_ctxt); - kfree(rule); - } -} - -int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule) -{ - struct selinux_audit_rule *tmprule; - struct role_datum *roledatum; - struct type_datum *typedatum; - struct user_datum *userdatum; - struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule; - int rc = 0; - - *rule = NULL; - - if (!ss_initialized) - return -EOPNOTSUPP; - - switch (field) { - case AUDIT_SUBJ_USER: - case AUDIT_SUBJ_ROLE: - case AUDIT_SUBJ_TYPE: - case AUDIT_OBJ_USER: - case AUDIT_OBJ_ROLE: - case AUDIT_OBJ_TYPE: - /* only 'equals' and 'not equals' fit user, role, and type */ - if (op != Audit_equal && op != Audit_not_equal) - return -EINVAL; - break; - case AUDIT_SUBJ_SEN: - case AUDIT_SUBJ_CLR: - case AUDIT_OBJ_LEV_LOW: - case AUDIT_OBJ_LEV_HIGH: - /* we do not allow a range, indicated by the presence of '-' */ - if (strchr(rulestr, '-')) - return -EINVAL; - break; - default: - /* only the above fields are valid */ - return -EINVAL; - } - - tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL); - if (!tmprule) - return -ENOMEM; - - context_init(&tmprule->au_ctxt); - - read_lock(&policy_rwlock); - - tmprule->au_seqno = latest_granting; - - switch (field) { - case AUDIT_SUBJ_USER: - case AUDIT_OBJ_USER: - rc = -EINVAL; - userdatum = hashtab_search(policydb.p_users.table, rulestr); - if (!userdatum) - goto out; - tmprule->au_ctxt.user = userdatum->value; - break; - case AUDIT_SUBJ_ROLE: - case AUDIT_OBJ_ROLE: - rc = -EINVAL; - roledatum = hashtab_search(policydb.p_roles.table, rulestr); - if (!roledatum) - goto out; - tmprule->au_ctxt.role = roledatum->value; - break; - case AUDIT_SUBJ_TYPE: - case AUDIT_OBJ_TYPE: - rc = -EINVAL; - typedatum = hashtab_search(policydb.p_types.table, rulestr); - if (!typedatum) - goto out; - tmprule->au_ctxt.type = typedatum->value; - break; - case AUDIT_SUBJ_SEN: - case AUDIT_SUBJ_CLR: - case AUDIT_OBJ_LEV_LOW: - case AUDIT_OBJ_LEV_HIGH: - rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC); - if (rc) - goto out; - break; - } - rc = 0; -out: - read_unlock(&policy_rwlock); - - if (rc) { - selinux_audit_rule_free(tmprule); - tmprule = NULL; - } - - *rule = tmprule; - - return rc; -} - -/* Check to see if the rule contains any selinux fields */ -int selinux_audit_rule_known(struct audit_krule *rule) -{ - int i; - - for (i = 0; i < rule->field_count; i++) { - struct audit_field *f = &rule->fields[i]; - switch (f->type) { - case AUDIT_SUBJ_USER: - case AUDIT_SUBJ_ROLE: - case AUDIT_SUBJ_TYPE: - case AUDIT_SUBJ_SEN: - case AUDIT_SUBJ_CLR: - case AUDIT_OBJ_USER: - case AUDIT_OBJ_ROLE: - case AUDIT_OBJ_TYPE: - case AUDIT_OBJ_LEV_LOW: - case AUDIT_OBJ_LEV_HIGH: - return 1; - } - } - - return 0; -} - -int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule, - struct audit_context *actx) -{ - struct context *ctxt; - struct mls_level *level; - struct selinux_audit_rule *rule = vrule; - int match = 0; - - if (!rule) { - audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR, - "selinux_audit_rule_match: missing rule\n"); - return -ENOENT; - } - - read_lock(&policy_rwlock); - - if (rule->au_seqno < latest_granting) { - audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR, - "selinux_audit_rule_match: stale rule\n"); - match = -ESTALE; - goto out; - } - - ctxt = sidtab_search(&sidtab, sid); - if (!ctxt) { - audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR, - "selinux_audit_rule_match: unrecognized SID %d\n", - sid); - match = -ENOENT; - goto out; - } - - /* a field/op pair that is not caught here will simply fall through - without a match */ - switch (field) { - case AUDIT_SUBJ_USER: - case AUDIT_OBJ_USER: - switch (op) { - case Audit_equal: - match = (ctxt->user == rule->au_ctxt.user); - break; - case Audit_not_equal: - match = (ctxt->user != rule->au_ctxt.user); - break; - } - break; - case AUDIT_SUBJ_ROLE: - case AUDIT_OBJ_ROLE: - switch (op) { - case Audit_equal: - match = (ctxt->role == rule->au_ctxt.role); - break; - case Audit_not_equal: - match = (ctxt->role != rule->au_ctxt.role); - break; - } - break; - case AUDIT_SUBJ_TYPE: - case AUDIT_OBJ_TYPE: - switch (op) { - case Audit_equal: - match = (ctxt->type == rule->au_ctxt.type); - break; - case Audit_not_equal: - match = (ctxt->type != rule->au_ctxt.type); - break; - } - break; - case AUDIT_SUBJ_SEN: - case AUDIT_SUBJ_CLR: - case AUDIT_OBJ_LEV_LOW: - case AUDIT_OBJ_LEV_HIGH: - level = ((field == AUDIT_SUBJ_SEN || - field == AUDIT_OBJ_LEV_LOW) ? - &ctxt->range.level[0] : &ctxt->range.level[1]); - switch (op) { - case Audit_equal: - match = mls_level_eq(&rule->au_ctxt.range.level[0], - level); - break; - case Audit_not_equal: - match = !mls_level_eq(&rule->au_ctxt.range.level[0], - level); - break; - case Audit_lt: - match = (mls_level_dom(&rule->au_ctxt.range.level[0], - level) && - !mls_level_eq(&rule->au_ctxt.range.level[0], - level)); - break; - case Audit_le: - match = mls_level_dom(&rule->au_ctxt.range.level[0], - level); - break; - case Audit_gt: - match = (mls_level_dom(level, - &rule->au_ctxt.range.level[0]) && - !mls_level_eq(level, - &rule->au_ctxt.range.level[0])); - break; - case Audit_ge: - match = mls_level_dom(level, - &rule->au_ctxt.range.level[0]); - break; - } - } - -out: - read_unlock(&policy_rwlock); - return match; -} - -static int (*aurule_callback)(void) = audit_update_lsm_rules; - -static int aurule_avc_callback(u32 event, u32 ssid, u32 tsid, - u16 class, u32 perms, u32 *retained) -{ - int err = 0; - - if (event == AVC_CALLBACK_RESET && aurule_callback) - err = aurule_callback(); - return err; -} - -static int __init aurule_init(void) -{ - int err; - - err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET, - SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0); - if (err) - panic("avc_add_callback() failed, error %d\n", err); - - return err; -} -__initcall(aurule_init); - -#ifdef CONFIG_NETLABEL -/** - * security_netlbl_cache_add - Add an entry to the NetLabel cache - * @secattr: the NetLabel packet security attributes - * @sid: the SELinux SID - * - * Description: - * Attempt to cache the context in @ctx, which was derived from the packet in - * @skb, in the NetLabel subsystem cache. This function assumes @secattr has - * already been initialized. - * - */ -static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr, - u32 sid) -{ - u32 *sid_cache; - - sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC); - if (sid_cache == NULL) - return; - secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC); - if (secattr->cache == NULL) { - kfree(sid_cache); - return; - } - - *sid_cache = sid; - secattr->cache->free = kfree; - secattr->cache->data = sid_cache; - secattr->flags |= NETLBL_SECATTR_CACHE; -} - -/** - * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID - * @secattr: the NetLabel packet security attributes - * @sid: the SELinux SID - * - * Description: - * Convert the given NetLabel security attributes in @secattr into a - * SELinux SID. If the @secattr field does not contain a full SELinux - * SID/context then use SECINITSID_NETMSG as the foundation. If possible the - * 'cache' field of @secattr is set and the CACHE flag is set; this is to - * allow the @secattr to be used by NetLabel to cache the secattr to SID - * conversion for future lookups. Returns zero on success, negative values on - * failure. - * - */ -int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr, - u32 *sid) -{ - int rc; - struct context *ctx; - struct context ctx_new; - - if (!ss_initialized) { - *sid = SECSID_NULL; - return 0; - } - - read_lock(&policy_rwlock); - - if (secattr->flags & NETLBL_SECATTR_CACHE) - *sid = *(u32 *)secattr->cache->data; - else if (secattr->flags & NETLBL_SECATTR_SECID) - *sid = secattr->attr.secid; - else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) { - rc = -EIDRM; - ctx = sidtab_search(&sidtab, SECINITSID_NETMSG); - if (ctx == NULL) - goto out; - - context_init(&ctx_new); - ctx_new.user = ctx->user; - ctx_new.role = ctx->role; - ctx_new.type = ctx->type; - mls_import_netlbl_lvl(&ctx_new, secattr); - if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { - rc = ebitmap_netlbl_import(&ctx_new.range.level[0].cat, - secattr->attr.mls.cat); - if (rc) - goto out; - memcpy(&ctx_new.range.level[1].cat, - &ctx_new.range.level[0].cat, - sizeof(ctx_new.range.level[0].cat)); - } - rc = -EIDRM; - if (!mls_context_isvalid(&policydb, &ctx_new)) - goto out_free; - - rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid); - if (rc) - goto out_free; - - security_netlbl_cache_add(secattr, *sid); - - ebitmap_destroy(&ctx_new.range.level[0].cat); - } else - *sid = SECSID_NULL; - - read_unlock(&policy_rwlock); - return 0; -out_free: - ebitmap_destroy(&ctx_new.range.level[0].cat); -out: - read_unlock(&policy_rwlock); - return rc; -} - -/** - * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr - * @sid: the SELinux SID - * @secattr: the NetLabel packet security attributes - * - * Description: - * Convert the given SELinux SID in @sid into a NetLabel security attribute. - * Returns zero on success, negative values on failure. - * - */ -int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr) -{ - int rc; - struct context *ctx; - - if (!ss_initialized) - return 0; - - read_lock(&policy_rwlock); - - rc = -ENOENT; - ctx = sidtab_search(&sidtab, sid); - if (ctx == NULL) - goto out; - - rc = -ENOMEM; - secattr->domain = kstrdup(sym_name(&policydb, SYM_TYPES, ctx->type - 1), - GFP_ATOMIC); - if (secattr->domain == NULL) - goto out; - - secattr->attr.secid = sid; - secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID; - mls_export_netlbl_lvl(ctx, secattr); - rc = mls_export_netlbl_cat(ctx, secattr); -out: - read_unlock(&policy_rwlock); - return rc; -} -#endif /* CONFIG_NETLABEL */ - -/** - * security_read_policy - read the policy. - * @data: binary policy data - * @len: length of data in bytes - * - */ -int security_read_policy(void **data, size_t *len) -{ - int rc; - struct policy_file fp; - - if (!ss_initialized) - return -EINVAL; - - *len = security_policydb_len(); - - *data = vmalloc_user(*len); - if (!*data) - return -ENOMEM; - - fp.data = *data; - fp.len = *len; - - read_lock(&policy_rwlock); - rc = policydb_write(&policydb, &fp); - read_unlock(&policy_rwlock); - - if (rc) - return rc; - - *len = (unsigned long)fp.data - (unsigned long)*data; - return 0; - -} |