| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Implementation of the security services. |
| * |
| * Authors : Stephen Smalley, <sds@tycho.nsa.gov> |
| * 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> |
| */ |
| #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/vmalloc.h> |
| #include <linux/lsm_hooks.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" |
| #include "policycap_names.h" |
| #include "ima.h" |
| |
| struct selinux_policy_convert_data { |
| struct convert_context_args args; |
| struct sidtab_convert_params sidtab_params; |
| }; |
| |
| /* Forward declaration. */ |
| static int context_struct_to_string(struct policydb *policydb, |
| struct context *context, |
| char **scontext, |
| u32 *scontext_len); |
| |
| static int sidtab_entry_to_string(struct policydb *policydb, |
| struct sidtab *sidtab, |
| struct sidtab_entry *entry, |
| char **scontext, |
| u32 *scontext_len); |
| |
| static void context_struct_compute_av(struct policydb *policydb, |
| struct context *scontext, |
| struct context *tcontext, |
| u16 tclass, |
| struct av_decision *avd, |
| struct extended_perms *xperms); |
| |
| static int selinux_set_mapping(struct policydb *pol, |
| const struct security_class_mapping *map, |
| struct selinux_map *out_map) |
| { |
| 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->mapping = kcalloc(++i, sizeof(*out_map->mapping), GFP_ATOMIC); |
| if (!out_map->mapping) |
| return -ENOMEM; |
| |
| /* Store the raw class and permission values */ |
| j = 0; |
| while (map[j].name) { |
| const struct security_class_mapping *p_in = map + (j++); |
| struct selinux_mapping *p_out = out_map->mapping + 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) { |
| pr_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[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]) { |
| pr_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) |
| pr_info("SELinux: the above unknown classes and permissions will be %s\n", |
| pol->allow_unknown ? "allowed" : "denied"); |
| |
| out_map->size = i; |
| return 0; |
| err: |
| kfree(out_map->mapping); |
| out_map->mapping = NULL; |
| return -EINVAL; |
| } |
| |
| /* |
| * Get real, policy values from mapped values |
| */ |
| |
| static u16 unmap_class(struct selinux_map *map, u16 tclass) |
| { |
| if (tclass < map->size) |
| return map->mapping[tclass].value; |
| |
| return tclass; |
| } |
| |
| /* |
| * Get kernel value for class from its policy value |
| */ |
| static u16 map_class(struct selinux_map *map, u16 pol_value) |
| { |
| u16 i; |
| |
| for (i = 1; i < map->size; i++) { |
| if (map->mapping[i].value == pol_value) |
| return i; |
| } |
| |
| return SECCLASS_NULL; |
| } |
| |
| static void map_decision(struct selinux_map *map, |
| u16 tclass, struct av_decision *avd, |
| int allow_unknown) |
| { |
| if (tclass < map->size) { |
| struct selinux_mapping *mapping = &map->mapping[tclass]; |
| unsigned int i, n = mapping->num_perms; |
| u32 result; |
| |
| for (i = 0, result = 0; i < n; i++) { |
| if (avd->allowed & mapping->perms[i]) |
| result |= 1<<i; |
| if (allow_unknown && !mapping->perms[i]) |
| result |= 1<<i; |
| } |
| avd->allowed = result; |
| |
| for (i = 0, result = 0; i < n; i++) |
| if (avd->auditallow & mapping->perms[i]) |
| result |= 1<<i; |
| avd->auditallow = result; |
| |
| for (i = 0, result = 0; i < n; i++) { |
| if (avd->auditdeny & mapping->perms[i]) |
| result |= 1<<i; |
| if (!allow_unknown && !mapping->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) |
| { |
| int mls_enabled; |
| struct selinux_policy *policy; |
| |
| if (!selinux_initialized()) |
| return 0; |
| |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| mls_enabled = policy->policydb.mls_enabled; |
| rcu_read_unlock(); |
| return 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 policydb *policydb, |
| 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 policydb *policydb, |
| 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(policydb, scontext, |
| &scontext_name, &length) < 0) |
| goto out; |
| |
| if (context_struct_to_string(policydb, tcontext, |
| &tcontext_name, &length) < 0) |
| goto out; |
| |
| /* audit a message */ |
| ab = audit_log_start(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); |
| } |
| |
| /* |
| * security_boundary_permission - drops violated permissions |
| * on boundary constraint. |
| */ |
| static void type_attribute_bounds_av(struct policydb *policydb, |
| struct context *scontext, |
| struct context *tcontext, |
| u16 tclass, |
| struct av_decision *avd) |
| { |
| struct context lo_scontext; |
| struct context lo_tcontext, *tcontextp = tcontext; |
| struct av_decision lo_avd; |
| struct type_datum *source; |
| struct type_datum *target; |
| u32 masked = 0; |
| |
| source = policydb->type_val_to_struct[scontext->type - 1]; |
| BUG_ON(!source); |
| |
| if (!source->bounds) |
| return; |
| |
| target = policydb->type_val_to_struct[tcontext->type - 1]; |
| BUG_ON(!target); |
| |
| memset(&lo_avd, 0, sizeof(lo_avd)); |
| |
| memcpy(&lo_scontext, scontext, sizeof(lo_scontext)); |
| lo_scontext.type = source->bounds; |
| |
| if (target->bounds) { |
| memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext)); |
| lo_tcontext.type = target->bounds; |
| tcontextp = &lo_tcontext; |
| } |
| |
| context_struct_compute_av(policydb, &lo_scontext, |
| tcontextp, |
| tclass, |
| &lo_avd, |
| NULL); |
| |
| masked = ~lo_avd.allowed & avd->allowed; |
| |
| if (likely(!masked)) |
| return; /* no masked permission */ |
| |
| /* mask violated permissions */ |
| avd->allowed &= ~masked; |
| |
| /* audit masked permissions */ |
| security_dump_masked_av(policydb, scontext, tcontext, |
| tclass, masked, "bounds"); |
| } |
| |
| /* |
| * flag which drivers have permissions |
| * only looking for ioctl based extended permssions |
| */ |
| void services_compute_xperms_drivers( |
| struct extended_perms *xperms, |
| struct avtab_node *node) |
| { |
| unsigned int i; |
| |
| if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { |
| /* if one or more driver has all permissions allowed */ |
| for (i = 0; i < ARRAY_SIZE(xperms->drivers.p); i++) |
| xperms->drivers.p[i] |= node->datum.u.xperms->perms.p[i]; |
| } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { |
| /* if allowing permissions within a driver */ |
| security_xperm_set(xperms->drivers.p, |
| node->datum.u.xperms->driver); |
| } |
| |
| xperms->len = 1; |
| } |
| |
| /* |
| * Compute access vectors and extended permissions based on a context |
| * structure pair for the permissions in a particular class. |
| */ |
| static void context_struct_compute_av(struct policydb *policydb, |
| struct context *scontext, |
| struct context *tcontext, |
| u16 tclass, |
| struct av_decision *avd, |
| struct extended_perms *xperms) |
| { |
| 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 (xperms) { |
| memset(&xperms->drivers, 0, sizeof(xperms->drivers)); |
| xperms->len = 0; |
| } |
| |
| if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) { |
| if (printk_ratelimit()) |
| pr_warn("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 | AVTAB_XPERMS; |
| sattr = &policydb->type_attr_map_array[scontext->type - 1]; |
| tattr = &policydb->type_attr_map_array[tcontext->type - 1]; |
| 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.u.data; |
| else if (node->key.specified == AVTAB_AUDITALLOW) |
| avd->auditallow |= node->datum.u.data; |
| else if (node->key.specified == AVTAB_AUDITDENY) |
| avd->auditdeny &= node->datum.u.data; |
| else if (xperms && (node->key.specified & AVTAB_XPERMS)) |
| services_compute_xperms_drivers(xperms, node); |
| } |
| |
| /* Check conditional av table for additional permissions */ |
| cond_compute_av(&policydb->te_cond_avtab, &avkey, |
| avd, xperms); |
| |
| } |
| } |
| |
| /* |
| * 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(policydb, 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(policydb, scontext, tcontext, |
| tclass, avd); |
| } |
| |
| static int security_validtrans_handle_fail(struct selinux_policy *policy, |
| struct sidtab_entry *oentry, |
| struct sidtab_entry *nentry, |
| struct sidtab_entry *tentry, |
| u16 tclass) |
| { |
| struct policydb *p = &policy->policydb; |
| struct sidtab *sidtab = policy->sidtab; |
| char *o = NULL, *n = NULL, *t = NULL; |
| u32 olen, nlen, tlen; |
| |
| if (sidtab_entry_to_string(p, sidtab, oentry, &o, &olen)) |
| goto out; |
| if (sidtab_entry_to_string(p, sidtab, nentry, &n, &nlen)) |
| goto out; |
| if (sidtab_entry_to_string(p, sidtab, tentry, &t, &tlen)) |
| goto out; |
| audit_log(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR, |
| "op=security_validate_transition seresult=denied" |
| " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s", |
| o, n, t, sym_name(p, SYM_CLASSES, tclass-1)); |
| out: |
| kfree(o); |
| kfree(n); |
| kfree(t); |
| |
| if (!enforcing_enabled()) |
| return 0; |
| return -EPERM; |
| } |
| |
| static int security_compute_validatetrans(u32 oldsid, u32 newsid, u32 tasksid, |
| u16 orig_tclass, bool user) |
| { |
| struct selinux_policy *policy; |
| struct policydb *policydb; |
| struct sidtab *sidtab; |
| struct sidtab_entry *oentry; |
| struct sidtab_entry *nentry; |
| struct sidtab_entry *tentry; |
| struct class_datum *tclass_datum; |
| struct constraint_node *constraint; |
| u16 tclass; |
| int rc = 0; |
| |
| |
| if (!selinux_initialized()) |
| return 0; |
| |
| rcu_read_lock(); |
| |
| policy = rcu_dereference(selinux_state.policy); |
| policydb = &policy->policydb; |
| sidtab = policy->sidtab; |
| |
| if (!user) |
| tclass = unmap_class(&policy->map, orig_tclass); |
| else |
| tclass = orig_tclass; |
| |
| if (!tclass || tclass > policydb->p_classes.nprim) { |
| rc = -EINVAL; |
| goto out; |
| } |
| tclass_datum = policydb->class_val_to_struct[tclass - 1]; |
| |
| oentry = sidtab_search_entry(sidtab, oldsid); |
| if (!oentry) { |
| pr_err("SELinux: %s: unrecognized SID %d\n", |
| __func__, oldsid); |
| rc = -EINVAL; |
| goto out; |
| } |
| |
| nentry = sidtab_search_entry(sidtab, newsid); |
| if (!nentry) { |
| pr_err("SELinux: %s: unrecognized SID %d\n", |
| __func__, newsid); |
| rc = -EINVAL; |
| goto out; |
| } |
| |
| tentry = sidtab_search_entry(sidtab, tasksid); |
| if (!tentry) { |
| pr_err("SELinux: %s: unrecognized SID %d\n", |
| __func__, tasksid); |
| rc = -EINVAL; |
| goto out; |
| } |
| |
| constraint = tclass_datum->validatetrans; |
| while (constraint) { |
| if (!constraint_expr_eval(policydb, &oentry->context, |
| &nentry->context, &tentry->context, |
| constraint->expr)) { |
| if (user) |
| rc = -EPERM; |
| else |
| rc = security_validtrans_handle_fail(policy, |
| oentry, |
| nentry, |
| tentry, |
| tclass); |
| goto out; |
| } |
| constraint = constraint->next; |
| } |
| |
| out: |
| rcu_read_unlock(); |
| return rc; |
| } |
| |
| int security_validate_transition_user(u32 oldsid, u32 newsid, u32 tasksid, |
| u16 tclass) |
| { |
| return security_compute_validatetrans(oldsid, newsid, tasksid, |
| tclass, true); |
| } |
| |
| int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid, |
| u16 orig_tclass) |
| { |
| return security_compute_validatetrans(oldsid, newsid, tasksid, |
| orig_tclass, false); |
| } |
| |
| /* |
| * 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 selinux_policy *policy; |
| struct policydb *policydb; |
| struct sidtab *sidtab; |
| struct sidtab_entry *old_entry, *new_entry; |
| struct type_datum *type; |
| int index; |
| int rc; |
| |
| if (!selinux_initialized()) |
| return 0; |
| |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| policydb = &policy->policydb; |
| sidtab = policy->sidtab; |
| |
| rc = -EINVAL; |
| old_entry = sidtab_search_entry(sidtab, old_sid); |
| if (!old_entry) { |
| pr_err("SELinux: %s: unrecognized SID %u\n", |
| __func__, old_sid); |
| goto out; |
| } |
| |
| rc = -EINVAL; |
| new_entry = sidtab_search_entry(sidtab, new_sid); |
| if (!new_entry) { |
| pr_err("SELinux: %s: unrecognized SID %u\n", |
| __func__, new_sid); |
| goto out; |
| } |
| |
| rc = 0; |
| /* type/domain unchanged */ |
| if (old_entry->context.type == new_entry->context.type) |
| goto out; |
| |
| index = new_entry->context.type; |
| while (true) { |
| type = policydb->type_val_to_struct[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_entry->context.type) |
| break; |
| |
| index = type->bounds; |
| } |
| |
| if (rc) { |
| char *old_name = NULL; |
| char *new_name = NULL; |
| u32 length; |
| |
| if (!sidtab_entry_to_string(policydb, sidtab, old_entry, |
| &old_name, &length) && |
| !sidtab_entry_to_string(policydb, sidtab, new_entry, |
| &new_name, &length)) { |
| audit_log(audit_context(), |
| GFP_ATOMIC, AUDIT_SELINUX_ERR, |
| "op=security_bounded_transition " |
| "seresult=denied " |
| "oldcontext=%s newcontext=%s", |
| old_name, new_name); |
| } |
| kfree(new_name); |
| kfree(old_name); |
| } |
| out: |
| rcu_read_unlock(); |
| |
| return rc; |
| } |
| |
| static void avd_init(struct selinux_policy *policy, struct av_decision *avd) |
| { |
| avd->allowed = 0; |
| avd->auditallow = 0; |
| avd->auditdeny = 0xffffffff; |
| if (policy) |
| avd->seqno = policy->latest_granting; |
| else |
| avd->seqno = 0; |
| avd->flags = 0; |
| } |
| |
| void services_compute_xperms_decision(struct extended_perms_decision *xpermd, |
| struct avtab_node *node) |
| { |
| unsigned int i; |
| |
| if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { |
| if (xpermd->driver != node->datum.u.xperms->driver) |
| return; |
| } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { |
| if (!security_xperm_test(node->datum.u.xperms->perms.p, |
| xpermd->driver)) |
| return; |
| } else { |
| BUG(); |
| } |
| |
| if (node->key.specified == AVTAB_XPERMS_ALLOWED) { |
| xpermd->used |= XPERMS_ALLOWED; |
| if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { |
| memset(xpermd->allowed->p, 0xff, |
| sizeof(xpermd->allowed->p)); |
| } |
| if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { |
| for (i = 0; i < ARRAY_SIZE(xpermd->allowed->p); i++) |
| xpermd->allowed->p[i] |= |
| node->datum.u.xperms->perms.p[i]; |
| } |
| } else if (node->key.specified == AVTAB_XPERMS_AUDITALLOW) { |
| xpermd->used |= XPERMS_AUDITALLOW; |
| if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { |
| memset(xpermd->auditallow->p, 0xff, |
| sizeof(xpermd->auditallow->p)); |
| } |
| if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { |
| for (i = 0; i < ARRAY_SIZE(xpermd->auditallow->p); i++) |
| xpermd->auditallow->p[i] |= |
| node->datum.u.xperms->perms.p[i]; |
| } |
| } else if (node->key.specified == AVTAB_XPERMS_DONTAUDIT) { |
| xpermd->used |= XPERMS_DONTAUDIT; |
| if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { |
| memset(xpermd->dontaudit->p, 0xff, |
| sizeof(xpermd->dontaudit->p)); |
| } |
| if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { |
| for (i = 0; i < ARRAY_SIZE(xpermd->dontaudit->p); i++) |
| xpermd->dontaudit->p[i] |= |
| node->datum.u.xperms->perms.p[i]; |
| } |
| } else { |
| BUG(); |
| } |
| } |
| |
| void security_compute_xperms_decision(u32 ssid, |
| u32 tsid, |
| u16 orig_tclass, |
| u8 driver, |
| struct extended_perms_decision *xpermd) |
| { |
| struct selinux_policy *policy; |
| struct policydb *policydb; |
| struct sidtab *sidtab; |
| u16 tclass; |
| struct context *scontext, *tcontext; |
| struct avtab_key avkey; |
| struct avtab_node *node; |
| struct ebitmap *sattr, *tattr; |
| struct ebitmap_node *snode, *tnode; |
| unsigned int i, j; |
| |
| xpermd->driver = driver; |
| xpermd->used = 0; |
| memset(xpermd->allowed->p, 0, sizeof(xpermd->allowed->p)); |
| memset(xpermd->auditallow->p, 0, sizeof(xpermd->auditallow->p)); |
| memset(xpermd->dontaudit->p, 0, sizeof(xpermd->dontaudit->p)); |
| |
| rcu_read_lock(); |
| if (!selinux_initialized()) |
| goto allow; |
| |
| policy = rcu_dereference(selinux_state.policy); |
| policydb = &policy->policydb; |
| sidtab = policy->sidtab; |
| |
| scontext = sidtab_search(sidtab, ssid); |
| if (!scontext) { |
| pr_err("SELinux: %s: unrecognized SID %d\n", |
| __func__, ssid); |
| goto out; |
| } |
| |
| tcontext = sidtab_search(sidtab, tsid); |
| if (!tcontext) { |
| pr_err("SELinux: %s: unrecognized SID %d\n", |
| __func__, tsid); |
| goto out; |
| } |
| |
| tclass = unmap_class(&policy->map, orig_tclass); |
| if (unlikely(orig_tclass && !tclass)) { |
| if (policydb->allow_unknown) |
| goto allow; |
| goto out; |
| } |
| |
| |
| if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) { |
| pr_warn_ratelimited("SELinux: Invalid class %hu\n", tclass); |
| goto out; |
| } |
| |
| avkey.target_class = tclass; |
| avkey.specified = AVTAB_XPERMS; |
| sattr = &policydb->type_attr_map_array[scontext->type - 1]; |
| tattr = &policydb->type_attr_map_array[tcontext->type - 1]; |
| 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)) |
| services_compute_xperms_decision(xpermd, node); |
| |
| cond_compute_xperms(&policydb->te_cond_avtab, |
| &avkey, xpermd); |
| } |
| } |
| out: |
| rcu_read_unlock(); |
| return; |
| allow: |
| memset(xpermd->allowed->p, 0xff, sizeof(xpermd->allowed->p)); |
| goto out; |
| } |
| |
| /** |
| * security_compute_av - Compute access vector decisions. |
| * @ssid: source security identifier |
| * @tsid: target security identifier |
| * @orig_tclass: target security class |
| * @avd: access vector decisions |
| * @xperms: extended permissions |
| * |
| * 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, |
| struct extended_perms *xperms) |
| { |
| struct selinux_policy *policy; |
| struct policydb *policydb; |
| struct sidtab *sidtab; |
| u16 tclass; |
| struct context *scontext = NULL, *tcontext = NULL; |
| |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| avd_init(policy, avd); |
| xperms->len = 0; |
| if (!selinux_initialized()) |
| goto allow; |
| |
| policydb = &policy->policydb; |
| sidtab = policy->sidtab; |
| |
| scontext = sidtab_search(sidtab, ssid); |
| if (!scontext) { |
| pr_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) { |
| pr_err("SELinux: %s: unrecognized SID %d\n", |
| __func__, tsid); |
| goto out; |
| } |
| |
| tclass = unmap_class(&policy->map, orig_tclass); |
| if (unlikely(orig_tclass && !tclass)) { |
| if (policydb->allow_unknown) |
| goto allow; |
| goto out; |
| } |
| context_struct_compute_av(policydb, scontext, tcontext, tclass, avd, |
| xperms); |
| map_decision(&policy->map, orig_tclass, avd, |
| policydb->allow_unknown); |
| out: |
| rcu_read_unlock(); |
| return; |
| allow: |
| avd->allowed = 0xffffffff; |
| goto out; |
| } |
| |
| void security_compute_av_user(u32 ssid, |
| u32 tsid, |
| u16 tclass, |
| struct av_decision *avd) |
| { |
| struct selinux_policy *policy; |
| struct policydb *policydb; |
| struct sidtab *sidtab; |
| struct context *scontext = NULL, *tcontext = NULL; |
| |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| avd_init(policy, avd); |
| if (!selinux_initialized()) |
| goto allow; |
| |
| policydb = &policy->policydb; |
| sidtab = policy->sidtab; |
| |
| scontext = sidtab_search(sidtab, ssid); |
| if (!scontext) { |
| pr_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) { |
| pr_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(policydb, scontext, tcontext, tclass, avd, |
| NULL); |
| out: |
| rcu_read_unlock(); |
| 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 policydb *p, |
| struct context *context, |
| char **scontext, u32 *scontext_len) |
| { |
| char *scontextp; |
| |
| if (scontext) |
| *scontext = NULL; |
| *scontext_len = 0; |
| |
| if (context->len) { |
| *scontext_len = context->len; |
| if (scontext) { |
| *scontext = kstrdup(context->str, GFP_ATOMIC); |
| if (!(*scontext)) |
| return -ENOMEM; |
| } |
| return 0; |
| } |
| |
| /* Compute the size of the context. */ |
| *scontext_len += strlen(sym_name(p, SYM_USERS, context->user - 1)) + 1; |
| *scontext_len += strlen(sym_name(p, SYM_ROLES, context->role - 1)) + 1; |
| *scontext_len += strlen(sym_name(p, SYM_TYPES, context->type - 1)) + 1; |
| *scontext_len += mls_compute_context_len(p, 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. |
| */ |
| scontextp += sprintf(scontextp, "%s:%s:%s", |
| sym_name(p, SYM_USERS, context->user - 1), |
| sym_name(p, SYM_ROLES, context->role - 1), |
| sym_name(p, SYM_TYPES, context->type - 1)); |
| |
| mls_sid_to_context(p, context, &scontextp); |
| |
| *scontextp = 0; |
| |
| return 0; |
| } |
| |
| static int sidtab_entry_to_string(struct policydb *p, |
| struct sidtab *sidtab, |
| struct sidtab_entry *entry, |
| char **scontext, u32 *scontext_len) |
| { |
| int rc = sidtab_sid2str_get(sidtab, entry, scontext, scontext_len); |
| |
| if (rc != -ENOENT) |
| return rc; |
| |
| rc = context_struct_to_string(p, &entry->context, scontext, |
| scontext_len); |
| if (!rc && scontext) |
| sidtab_sid2str_put(sidtab, entry, *scontext, *scontext_len); |
| return rc; |
| } |
| |
| #include "initial_sid_to_string.h" |
| |
| int security_sidtab_hash_stats(char *page) |
| { |
| struct selinux_policy *policy; |
| int rc; |
| |
| if (!selinux_initialized()) { |
| pr_err("SELinux: %s: called before initial load_policy\n", |
| __func__); |
| return -EINVAL; |
| } |
| |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| rc = sidtab_hash_stats(policy->sidtab, page); |
| rcu_read_unlock(); |
| |
| return rc; |
| } |
| |
| 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, |
| int only_invalid) |
| { |
| struct selinux_policy *policy; |
| struct policydb *policydb; |
| struct sidtab *sidtab; |
| struct sidtab_entry *entry; |
| int rc = 0; |
| |
| if (scontext) |
| *scontext = NULL; |
| *scontext_len = 0; |
| |
| if (!selinux_initialized()) { |
| if (sid <= SECINITSID_NUM) { |
| char *scontextp; |
| const char *s = initial_sid_to_string[sid]; |
| |
| if (!s) |
| return -EINVAL; |
| *scontext_len = strlen(s) + 1; |
| if (!scontext) |
| return 0; |
| scontextp = kmemdup(s, *scontext_len, GFP_ATOMIC); |
| if (!scontextp) |
| return -ENOMEM; |
| *scontext = scontextp; |
| return 0; |
| } |
| pr_err("SELinux: %s: called before initial " |
| "load_policy on unknown SID %d\n", __func__, sid); |
| return -EINVAL; |
| } |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| policydb = &policy->policydb; |
| sidtab = policy->sidtab; |
| |
| if (force) |
| entry = sidtab_search_entry_force(sidtab, sid); |
| else |
| entry = sidtab_search_entry(sidtab, sid); |
| if (!entry) { |
| pr_err("SELinux: %s: unrecognized SID %d\n", |
| __func__, sid); |
| rc = -EINVAL; |
| goto out_unlock; |
| } |
| if (only_invalid && !entry->context.len) |
| goto out_unlock; |
| |
| rc = sidtab_entry_to_string(policydb, sidtab, entry, scontext, |
| scontext_len); |
| |
| out_unlock: |
| rcu_read_unlock(); |
| 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, 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, 0); |
| } |
| |
| /** |
| * security_sid_to_context_inval - Obtain a context for a given SID if it |
| * is invalid. |
| * @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, but only if the |
| * context is invalid in the current policy. Set @scontext to point to |
| * this string (or NULL if the context is valid) and set @scontext_len to |
| * the length of the string (or 0 if the context is valid). |
| */ |
| int security_sid_to_context_inval(u32 sid, |
| char **scontext, u32 *scontext_len) |
| { |
| return security_sid_to_context_core(sid, scontext, |
| scontext_len, 1, 1); |
| } |
| |
| /* |
| * Caveat: Mutates scontext. |
| */ |
| static int string_to_context_struct(struct policydb *pol, |
| struct sidtab *sidtabp, |
| char *scontext, |
| 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 = scontext; |
| |
| /* Extract the user. */ |
| p = scontextp; |
| while (*p && *p != ':') |
| p++; |
| |
| if (*p == 0) |
| goto out; |
| |
| *p++ = 0; |
| |
| usrdatum = symtab_search(&pol->p_users, 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 = symtab_search(&pol->p_roles, scontextp); |
| if (!role) |
| goto out; |
| ctx->role = role->value; |
| |
| /* Extract type. */ |
| scontextp = p; |
| while (*p && *p != ':') |
| p++; |
| oldc = *p; |
| *p++ = 0; |
| |
| typdatum = symtab_search(&pol->p_types, 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; |
| |
| /* Check the validity of the new context. */ |
| rc = -EINVAL; |
| 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) |
| { |
| struct selinux_policy *policy; |
| struct policydb *policydb; |
| struct sidtab *sidtab; |
| char *scontext2, *str = NULL; |
| struct context context; |
| int rc = 0; |
| |
| /* An empty security context is never valid. */ |
| if (!scontext_len) |
| return -EINVAL; |
| |
| /* Copy the string to allow changes and ensure a NUL terminator */ |
| scontext2 = kmemdup_nul(scontext, scontext_len, gfp_flags); |
| if (!scontext2) |
| return -ENOMEM; |
| |
| if (!selinux_initialized()) { |
| int i; |
| |
| for (i = 1; i < SECINITSID_NUM; i++) { |
| const char *s = initial_sid_to_string[i]; |
| |
| if (s && !strcmp(s, scontext2)) { |
| *sid = i; |
| goto out; |
| } |
| } |
| *sid = SECINITSID_KERNEL; |
| goto out; |
| } |
| *sid = SECSID_NULL; |
| |
| if (force) { |
| /* Save another copy for storing in uninterpreted form */ |
| rc = -ENOMEM; |
| str = kstrdup(scontext2, gfp_flags); |
| if (!str) |
| goto out; |
| } |
| retry: |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| policydb = &policy->policydb; |
| sidtab = policy->sidtab; |
| rc = string_to_context_struct(policydb, sidtab, scontext2, |
| &context, def_sid); |
| if (rc == -EINVAL && force) { |
| context.str = str; |
| context.len = strlen(str) + 1; |
| str = NULL; |
| } else if (rc) |
| goto out_unlock; |
| rc = sidtab_context_to_sid(sidtab, &context, sid); |
| if (rc == -ESTALE) { |
| rcu_read_unlock(); |
| if (context.str) { |
| str = context.str; |
| context.str = NULL; |
| } |
| context_destroy(&context); |
| goto retry; |
| } |
| context_destroy(&context); |
| out_unlock: |
| rcu_read_unlock(); |
| 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 |
| * @gfp: context for the allocation |
| * |
| * 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, |
| gfp_t gfp) |
| { |
| return security_context_to_sid_core(scontext, scontext_len, |
| sid, SECSID_NULL, gfp, 0); |
| } |
| |
| int security_context_str_to_sid(const char *scontext, u32 *sid, gfp_t gfp) |
| { |
| return security_context_to_sid(scontext, strlen(scontext), |
| sid, gfp); |
| } |
| |
| /** |
| * 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 |
| * @gfp_flags: the allocator get-free-page (GFP) flags |
| * |
| * 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 selinux_policy *policy, |
| struct sidtab_entry *sentry, |
| struct sidtab_entry *tentry, |
| u16 tclass, |
| struct context *newcontext) |
| { |
| struct policydb *policydb = &policy->policydb; |
| struct sidtab *sidtab = policy->sidtab; |
| char *s = NULL, *t = NULL, *n = NULL; |
| u32 slen, tlen, nlen; |
| struct audit_buffer *ab; |
| |
| if (sidtab_entry_to_string(policydb, sidtab, sentry, &s, &slen)) |
| goto out; |
| if (sidtab_entry_to_string(policydb, sidtab, tentry, &t, &tlen)) |
| goto out; |
| if (context_struct_to_string(policydb, newcontext, &n, &nlen)) |
| goto out; |
| ab = audit_log_start(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR); |
| if (!ab) |
| goto out; |
| audit_log_format(ab, |
| "op=security_compute_sid invalid_context="); |
| /* no need to record the NUL with untrusted strings */ |
| audit_log_n_untrustedstring(ab, n, nlen - 1); |
| audit_log_format(ab, " scontext=%s tcontext=%s tclass=%s", |
| s, t, sym_name(policydb, SYM_CLASSES, tclass-1)); |
| audit_log_end(ab); |
| out: |
| kfree(s); |
| kfree(t); |
| kfree(n); |
| if (!enforcing_enabled()) |
| return 0; |
| return -EACCES; |
| } |
| |
| static void filename_compute_type(struct policydb *policydb, |
| struct context *newcontext, |
| u32 stype, u32 ttype, u16 tclass, |
| const char *objname) |
| { |
| struct filename_trans_key ft; |
| struct filename_trans_datum *datum; |
| |
| /* |
| * 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(&policydb->filename_trans_ttypes, ttype)) |
| return; |
| |
| ft.ttype = ttype; |
| ft.tclass = tclass; |
| ft.name = objname; |
| |
| datum = policydb_filenametr_search(policydb, &ft); |
| while (datum) { |
| if (ebitmap_get_bit(&datum->stypes, stype - 1)) { |
| newcontext->type = datum->otype; |
| return; |
| } |
| datum = datum->next; |
| } |
| } |
| |
| static int security_compute_sid(u32 ssid, |
| u32 tsid, |
| u16 orig_tclass, |
| u32 specified, |
| const char *objname, |
| u32 *out_sid, |
| bool kern) |
| { |
| struct selinux_policy *policy; |
| struct policydb *policydb; |
| struct sidtab *sidtab; |
| struct class_datum *cladatum; |
| struct context *scontext, *tcontext, newcontext; |
| struct sidtab_entry *sentry, *tentry; |
| struct avtab_key avkey; |
| struct avtab_datum *avdatum; |
| struct avtab_node *node; |
| u16 tclass; |
| int rc = 0; |
| bool sock; |
| |
| if (!selinux_initialized()) { |
| switch (orig_tclass) { |
| case SECCLASS_PROCESS: /* kernel value */ |
| *out_sid = ssid; |
| break; |
| default: |
| *out_sid = tsid; |
| break; |
| } |
| goto out; |
| } |
| |
| retry: |
| cladatum = NULL; |
| context_init(&newcontext); |
| |
| rcu_read_lock(); |
| |
| policy = rcu_dereference(selinux_state.policy); |
| |
| if (kern) { |
| tclass = unmap_class(&policy->map, orig_tclass); |
| sock = security_is_socket_class(orig_tclass); |
| } else { |
| tclass = orig_tclass; |
| sock = security_is_socket_class(map_class(&policy->map, |
| tclass)); |
| } |
| |
| policydb = &policy->policydb; |
| sidtab = policy->sidtab; |
| |
| sentry = sidtab_search_entry(sidtab, ssid); |
| if (!sentry) { |
| pr_err("SELinux: %s: unrecognized SID %d\n", |
| __func__, ssid); |
| rc = -EINVAL; |
| goto out_unlock; |
| } |
| tentry = sidtab_search_entry(sidtab, tsid); |
| if (!tentry) { |
| pr_err("SELinux: %s: unrecognized SID %d\n", |
| __func__, tsid); |
| rc = -EINVAL; |
| goto out_unlock; |
| } |
| |
| scontext = &sentry->context; |
| tcontext = &tentry->context; |
| |
| if (tclass && tclass <= policydb->p_classes.nprim) |
| cladatum = policydb->class_val_to_struct[tclass - 1]; |
| |
| /* Set the user identity. */ |
| switch (specified) { |
| case AVTAB_TRANSITION: |
| case AVTAB_CHANGE: |
| if (cladatum && cladatum->default_user == DEFAULT_TARGET) { |
| newcontext.user = tcontext->user; |
| } else { |
| /* notice this gets both DEFAULT_SOURCE and unset */ |
| /* 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 to default values. */ |
| if (cladatum && cladatum->default_role == DEFAULT_SOURCE) { |
| newcontext.role = scontext->role; |
| } else if (cladatum && cladatum->default_role == DEFAULT_TARGET) { |
| newcontext.role = tcontext->role; |
| } else { |
| if ((tclass == policydb->process_class) || sock) |
| newcontext.role = scontext->role; |
| else |
| newcontext.role = OBJECT_R_VAL; |
| } |
| |
| /* Set the type to default values. */ |
| if (cladatum && cladatum->default_type == DEFAULT_SOURCE) { |
| newcontext.type = scontext->type; |
| } else if (cladatum && cladatum->default_type == DEFAULT_TARGET) { |
| newcontext.type = tcontext->type; |
| } else { |
| if ((tclass == policydb->process_class) || sock) { |
| /* Use the type of process. */ |
| newcontext.type = scontext->type; |
| } else { |
| /* 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->u.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. */ |
| struct role_trans_datum *rtd; |
| struct role_trans_key rtk = { |
| .role = scontext->role, |
| .type = tcontext->type, |
| .tclass = tclass, |
| }; |
| |
| rtd = policydb_roletr_search(policydb, &rtk); |
| if (rtd) |
| newcontext.role = rtd->new_role; |
| } |
| |
| /* Set the MLS attributes. |
| This is done last because it may allocate memory. */ |
| rc = mls_compute_sid(policydb, 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(policy, sentry, |
| tentry, tclass, |
| &newcontext); |
| if (rc) |
| goto out_unlock; |
| } |
| /* Obtain the sid for the context. */ |
| rc = sidtab_context_to_sid(sidtab, &newcontext, out_sid); |
| if (rc == -ESTALE) { |
| rcu_read_unlock(); |
| context_destroy(&newcontext); |
| goto retry; |
| } |
| out_unlock: |
| rcu_read_unlock(); |
| 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 |
| * @qstr: object name |
| * @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); |
| } |
| |
| static inline int convert_context_handle_invalid_context( |
| struct policydb *policydb, |
| struct context *context) |
| { |
| char *s; |
| u32 len; |
| |
| if (enforcing_enabled()) |
| return -EINVAL; |
| |
| if (!context_struct_to_string(policydb, context, &s, &len)) { |
| pr_warn("SELinux: Context %s would be invalid if enforcing\n", |
| s); |
| kfree(s); |
| } |
| return 0; |
| } |
| |
| /** |
| * services_convert_context - Convert a security context across policies. |
| * @args: populated convert_context_args struct |
| * @oldc: original context |
| * @newc: converted context |
| * @gfp_flags: allocation flags |
| * |
| * Convert the values in the security context structure @oldc from the values |
| * specified in the policy @args->oldp to the values specified in the policy |
| * @args->newp, storing the new context in @newc, and verifying that the |
| * context is valid under the new policy. |
| */ |
| int services_convert_context(struct convert_context_args *args, |
| struct context *oldc, struct context *newc, |
| gfp_t gfp_flags) |
| { |
| struct ocontext *oc; |
| struct role_datum *role; |
| struct type_datum *typdatum; |
| struct user_datum *usrdatum; |
| char *s; |
| u32 len; |
| int rc; |
| |
| if (oldc->str) { |
| s = kstrdup(oldc->str, gfp_flags); |
| if (!s) |
| return -ENOMEM; |
| |
| rc = string_to_context_struct(args->newp, NULL, s, newc, SECSID_NULL); |
| if (rc == -EINVAL) { |
| /* |
| * Retain string representation for later mapping. |
| * |
| * IMPORTANT: We need to copy the contents of oldc->str |
| * back into s again because string_to_context_struct() |
| * may have garbled it. |
| */ |
| memcpy(s, oldc->str, oldc->len); |
| context_init(newc); |
| newc->str = s; |
| newc->len = oldc->len; |
| return 0; |
| } |
| kfree(s); |
| if (rc) { |
| /* Other error condition, e.g. ENOMEM. */ |
| pr_err("SELinux: Unable to map context %s, rc = %d.\n", |
| oldc->str, -rc); |
| return rc; |
| } |
| pr_info("SELinux: Context %s became valid (mapped).\n", |
| oldc->str); |
| return 0; |
| } |
| |
| context_init(newc); |
| |
| /* Convert the user. */ |
| usrdatum = symtab_search(&args->newp->p_users, |
| sym_name(args->oldp, SYM_USERS, oldc->user - 1)); |
| if (!usrdatum) |
| goto bad; |
| newc->user = usrdatum->value; |
| |
| /* Convert the role. */ |
| role = symtab_search(&args->newp->p_roles, |
| sym_name(args->oldp, SYM_ROLES, oldc->role - 1)); |
| if (!role) |
| goto bad; |
| newc->role = role->value; |
| |
| /* Convert the type. */ |
| typdatum = symtab_search(&args->newp->p_types, |
| sym_name(args->oldp, SYM_TYPES, oldc->type - 1)); |
| if (!typdatum) |
| goto bad; |
| newc->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, oldc, newc); |
| if (rc) |
| goto bad; |
| } 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; |
| if (!oc) { |
| pr_err("SELinux: unable to look up" |
| " the initial SIDs list\n"); |
| goto bad; |
| } |
| rc = mls_range_set(newc, &oc->context[0].range); |
| if (rc) |
| goto bad; |
| } |
| |
| /* Check the validity of the new context. */ |
| if (!policydb_context_isvalid(args->newp, newc)) { |
| rc = convert_context_handle_invalid_context(args->oldp, oldc); |
| if (rc) |
| goto bad; |
| } |
| |
| return 0; |
| bad: |
| /* Map old representation to string and save it. */ |
| rc = context_struct_to_string(args->oldp, oldc, &s, &len); |
| if (rc) |
| return rc; |
| context_destroy(newc); |
| newc->str = s; |
| newc->len = len; |
| pr_info("SELinux: Context %s became invalid (unmapped).\n", |
| newc->str); |
| return 0; |
| } |
| |
| static void security_load_policycaps(struct selinux_policy *policy) |
| { |
| struct policydb *p; |
| unsigned int i; |
| struct ebitmap_node *node; |
| |
| p = &policy->policydb; |
| |
| for (i = 0; i < ARRAY_SIZE(selinux_state.policycap); i++) |
| WRITE_ONCE(selinux_state.policycap[i], |
| ebitmap_get_bit(&p->policycaps, i)); |
| |
| for (i = 0; i < ARRAY_SIZE(selinux_policycap_names); i++) |
| pr_info("SELinux: policy capability %s=%d\n", |
| selinux_policycap_names[i], |
| ebitmap_get_bit(&p->policycaps, i)); |
| |
| ebitmap_for_each_positive_bit(&p->policycaps, node, i) { |
| if (i >= ARRAY_SIZE(selinux_policycap_names)) |
| pr_info("SELinux: unknown policy capability %u\n", |
| i); |
| } |
| } |
| |
| static int security_preserve_bools(struct selinux_policy *oldpolicy, |
| struct selinux_policy *newpolicy); |
| |
| static void selinux_policy_free(struct selinux_policy *policy) |
| { |
| if (!policy) |
| return; |
| |
| sidtab_destroy(policy->sidtab); |
| kfree(policy->map.mapping); |
| policydb_destroy(&policy->policydb); |
| kfree(policy->sidtab); |
| kfree(policy); |
| } |
| |
| static void selinux_policy_cond_free(struct selinux_policy *policy) |
| { |
| cond_policydb_destroy_dup(&policy->policydb); |
| kfree(policy); |
| } |
| |
| void selinux_policy_cancel(struct selinux_load_state *load_state) |
| { |
| struct selinux_state *state = &selinux_state; |
| struct selinux_policy *oldpolicy; |
| |
| oldpolicy = rcu_dereference_protected(state->policy, |
| lockdep_is_held(&state->policy_mutex)); |
| |
| sidtab_cancel_convert(oldpolicy->sidtab); |
| selinux_policy_free(load_state->policy); |
| kfree(load_state->convert_data); |
| } |
| |
| static void selinux_notify_policy_change(u32 seqno) |
| { |
| /* Flush external caches and notify userspace of policy load */ |
| avc_ss_reset(seqno); |
| selnl_notify_policyload(seqno); |
| selinux_status_update_policyload(seqno); |
| selinux_netlbl_cache_invalidate(); |
| selinux_xfrm_notify_policyload(); |
| selinux_ima_measure_state_locked(); |
| } |
| |
| void selinux_policy_commit(struct selinux_load_state *load_state) |
| { |
| struct selinux_state *state = &selinux_state; |
| struct selinux_policy *oldpolicy, *newpolicy = load_state->policy; |
| unsigned long flags; |
| u32 seqno; |
| |
| oldpolicy = rcu_dereference_protected(state->policy, |
| lockdep_is_held(&state->policy_mutex)); |
| |
| /* If switching between different policy types, log MLS status */ |
| if (oldpolicy) { |
| if (oldpolicy->policydb.mls_enabled && !newpolicy->policydb.mls_enabled) |
| pr_info("SELinux: Disabling MLS support...\n"); |
| else if (!oldpolicy->policydb.mls_enabled && newpolicy->policydb.mls_enabled) |
| pr_info("SELinux: Enabling MLS support...\n"); |
| } |
| |
| /* Set latest granting seqno for new policy. */ |
| if (oldpolicy) |
| newpolicy->latest_granting = oldpolicy->latest_granting + 1; |
| else |
| newpolicy->latest_granting = 1; |
| seqno = newpolicy->latest_granting; |
| |
| /* Install the new policy. */ |
| if (oldpolicy) { |
| sidtab_freeze_begin(oldpolicy->sidtab, &flags); |
| rcu_assign_pointer(state->policy, newpolicy); |
| sidtab_freeze_end(oldpolicy->sidtab, &flags); |
| } else { |
| rcu_assign_pointer(state->policy, newpolicy); |
| } |
| |
| /* Load the policycaps from the new policy */ |
| security_load_policycaps(newpolicy); |
| |
| if (!selinux_initialized()) { |
| /* |
| * After first policy load, the security server is |
| * marked as initialized and ready to handle requests and |
| * any objects created prior to policy load are then labeled. |
| */ |
| selinux_mark_initialized(); |
| selinux_complete_init(); |
| } |
| |
| /* Free the old policy */ |
| synchronize_rcu(); |
| selinux_policy_free(oldpolicy); |
| kfree(load_state->convert_data); |
| |
| /* Notify others of the policy change */ |
| selinux_notify_policy_change(seqno); |
| } |
| |
| /** |
| * security_load_policy - Load a security policy configuration. |
| * @data: binary policy data |
| * @len: length of data in bytes |
| * @load_state: policy load state |
| * |
| * 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 selinux_load_state *load_state) |
| { |
| struct selinux_state *state = &selinux_state; |
| struct selinux_policy *newpolicy, *oldpolicy; |
| struct selinux_policy_convert_data *convert_data; |
| int rc = 0; |
| struct policy_file file = { data, len }, *fp = &file; |
| |
| newpolicy = kzalloc(sizeof(*newpolicy), GFP_KERNEL); |
| if (!newpolicy) |
| return -ENOMEM; |
| |
| newpolicy->sidtab = kzalloc(sizeof(*newpolicy->sidtab), GFP_KERNEL); |
| if (!newpolicy->sidtab) { |
| rc = -ENOMEM; |
| goto err_policy; |
| } |
| |
| rc = policydb_read(&newpolicy->policydb, fp); |
| if (rc) |
| goto err_sidtab; |
| |
| newpolicy->policydb.len = len; |
| rc = selinux_set_mapping(&newpolicy->policydb, secclass_map, |
| &newpolicy->map); |
| if (rc) |
| goto err_policydb; |
| |
| rc = policydb_load_isids(&newpolicy->policydb, newpolicy->sidtab); |
| if (rc) { |
| pr_err("SELinux: unable to load the initial SIDs\n"); |
| goto err_mapping; |
| } |
| |
| if (!selinux_initialized()) { |
| /* First policy load, so no need to preserve state from old policy */ |
| load_state->policy = newpolicy; |
| load_state->convert_data = NULL; |
| return 0; |
| } |
| |
| oldpolicy = rcu_dereference_protected(state->policy, |
| lockdep_is_held(&state->policy_mutex)); |
| |
| /* Preserve active boolean values from the old policy */ |
| rc = security_preserve_bools(oldpolicy, newpolicy); |
| if (rc) { |
| pr_err("SELinux: unable to preserve booleans\n"); |
| goto err_free_isids; |
| } |
| |
| /* |
| * Convert the internal representations of contexts |
| * in the new SID table. |
| */ |
| |
| convert_data = kmalloc(sizeof(*convert_data), GFP_KERNEL); |
| if (!convert_data) { |
| rc = -ENOMEM; |
| goto err_free_isids; |
| } |
| |
| convert_data->args.oldp = &oldpolicy->policydb; |
| convert_data->args.newp = &newpolicy->policydb; |
| |
| convert_data->sidtab_params.args = &convert_data->args; |
| convert_data->sidtab_params.target = newpolicy->sidtab; |
| |
| rc = sidtab_convert(oldpolicy->sidtab, &convert_data->sidtab_params); |
| if (rc) { |
| pr_err("SELinux: unable to convert the internal" |
| " representation of contexts in the new SID" |
| " table\n"); |
| goto err_free_convert_data; |
| } |
| |
| load_state->policy = newpolicy; |
| load_state->convert_data = convert_data; |
| return 0; |
| |
| err_free_convert_data: |
| kfree(convert_data); |
| err_free_isids: |
| sidtab_destroy(newpolicy->sidtab); |
| err_mapping: |
| kfree(newpolicy->map.mapping); |
| err_policydb: |
| policydb_destroy(&newpolicy->policydb); |
| err_sidtab: |
| kfree(newpolicy->sidtab); |
| err_policy: |
| kfree(newpolicy); |
| |
| return rc; |
| } |
| |
| /** |
| * ocontext_to_sid - Helper to safely get sid for an ocontext |
| * @sidtab: SID table |
| * @c: ocontext structure |
| * @index: index of the context entry (0 or 1) |
| * @out_sid: pointer to the resulting SID value |
| * |
| * For all ocontexts except OCON_ISID the SID fields are populated |
| * on-demand when needed. Since updating the SID value is an SMP-sensitive |
| * operation, this helper must be used to do that safely. |
| * |
| * WARNING: This function may return -ESTALE, indicating that the caller |
| * must retry the operation after re-acquiring the policy pointer! |
| */ |
| static int ocontext_to_sid(struct sidtab *sidtab, struct ocontext *c, |
| size_t index, u32 *out_sid) |
| { |
| int rc; |
| u32 sid; |
| |
| /* Ensure the associated sidtab entry is visible to this thread. */ |
| sid = smp_load_acquire(&c->sid[index]); |
| if (!sid) { |
| rc = sidtab_context_to_sid(sidtab, &c->context[index], &sid); |
| if (rc) |
| return rc; |
| |
| /* |
| * Ensure the new sidtab entry is visible to other threads |
| * when they see the SID. |
| */ |
| smp_store_release(&c->sid[index], sid); |
| } |
| *out_sid = sid; |
| return 0; |
| } |
| |
| /** |
| * 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 selinux_policy *policy; |
| struct policydb *policydb; |
| struct sidtab *sidtab; |
| struct ocontext *c; |
| int rc; |
| |
| if (!selinux_initialized()) { |
| *out_sid = SECINITSID_PORT; |
| return 0; |
| } |
| |
| retry: |
| rc = 0; |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| policydb = &policy->policydb; |
| sidtab = policy->sidtab; |
| |
| 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) { |
| rc = ocontext_to_sid(sidtab, c, 0, out_sid); |
| if (rc == -ESTALE) { |
| rcu_read_unlock(); |
| goto retry; |
| } |
| if (rc) |
| goto out; |
| } else { |
| *out_sid = SECINITSID_PORT; |
| } |
| |
| out: |
| rcu_read_unlock(); |
| return rc; |
| } |
| |
| /** |
| * security_ib_pkey_sid - Obtain the SID for a pkey. |
| * @subnet_prefix: Subnet Prefix |
| * @pkey_num: pkey number |
| * @out_sid: security identifier |
| */ |
| int security_ib_pkey_sid(u64 subnet_prefix, u16 pkey_num, u32 *out_sid) |
| { |
| struct selinux_policy *policy; |
| struct policydb *policydb; |
| struct sidtab *sidtab; |
| struct ocontext *c; |
| int rc; |
| |
| if (!selinux_initialized()) { |
| *out_sid = SECINITSID_UNLABELED; |
| return 0; |
| } |
| |
| retry: |
| rc = 0; |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| policydb = &policy->policydb; |
| sidtab = policy->sidtab; |
| |
| c = policydb->ocontexts[OCON_IBPKEY]; |
| while (c) { |
| if (c->u.ibpkey.low_pkey <= pkey_num && |
| c->u.ibpkey.high_pkey >= pkey_num && |
| c->u.ibpkey.subnet_prefix == subnet_prefix) |
| break; |
| |
| c = c->next; |
| } |
| |
| if (c) { |
| rc = ocontext_to_sid(sidtab, c, 0, out_sid); |
| if (rc == -ESTALE) { |
| rcu_read_unlock(); |
| goto retry; |
| } |
| if (rc) |
| goto out; |
| } else |
| *out_sid = SECINITSID_UNLABELED; |
| |
| out: |
| rcu_read_unlock(); |
| return rc; |
| } |
| |
| /** |
| * security_ib_endport_sid - Obtain the SID for a subnet management interface. |
| * @dev_name: device name |
| * @port_num: port number |
| * @out_sid: security identifier |
| */ |
| int security_ib_endport_sid(const char *dev_name, u8 port_num, u32 *out_sid) |
| { |
| struct selinux_policy *policy; |
| struct policydb *policydb; |
| struct sidtab *sidtab; |
| struct ocontext *c; |
| int rc; |
| |
| if (!selinux_initialized()) { |
| *out_sid = SECINITSID_UNLABELED; |
| return 0; |
| } |
| |
| retry: |
| rc = 0; |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| policydb = &policy->policydb; |
| sidtab = policy->sidtab; |
| |
| c = policydb->ocontexts[OCON_IBENDPORT]; |
| while (c) { |
| if (c->u.ibendport.port == port_num && |
| !strncmp(c->u.ibendport.dev_name, |
| dev_name, |
| IB_DEVICE_NAME_MAX)) |
| break; |
| |
| c = c->next; |
| } |
| |
| if (c) { |
| rc = ocontext_to_sid(sidtab, c, 0, out_sid); |
| if (rc == -ESTALE) { |
| rcu_read_unlock(); |
| goto retry; |
| } |
| if (rc) |
| goto out; |
| } else |
| *out_sid = SECINITSID_UNLABELED; |
| |
| out: |
| rcu_read_unlock(); |
| 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) |
| { |
| struct selinux_policy *policy; |
| struct policydb *policydb; |
| struct sidtab *sidtab; |
| int rc; |
| struct ocontext *c; |
| |
| if (!selinux_initialized()) { |
| *if_sid = SECINITSID_NETIF; |
| return 0; |
| } |
| |
| retry: |
| rc = 0; |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| policydb = &policy->policydb; |
| sidtab = policy->sidtab; |
| |
| c = policydb->ocontexts[OCON_NETIF]; |
| while (c) { |
| if (strcmp(name, c->u.name) == 0) |
| break; |
| c = c->next; |
| } |
| |
| if (c) { |
| rc = ocontext_to_sid(sidtab, c, 0, if_sid); |
| if (rc == -ESTALE) { |
| rcu_read_unlock(); |
| goto retry; |
| } |
| if (rc) |
| goto out; |
| } else |
| *if_sid = SECINITSID_NETIF; |
| |
| out: |
| rcu_read_unlock(); |
| 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) |
| { |
| struct selinux_policy *policy; |
| struct policydb *policydb; |
| struct sidtab *sidtab; |
| int rc; |
| struct ocontext *c; |
| |
| if (!selinux_initialized()) { |
| *out_sid = SECINITSID_NODE; |
| return 0; |
| } |
| |
| retry: |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| policydb = &policy->policydb; |
| sidtab = policy->sidtab; |
| |
| 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) { |
| rc = ocontext_to_sid(sidtab, c, 0, out_sid); |
| if (rc == -ESTALE) { |
| rcu_read_unlock(); |
| goto retry; |
| } |
| if (rc) |
| goto out; |
| } else { |
| *out_sid = SECINITSID_NODE; |
| } |
| |
| rc = 0; |
| out: |
| rcu_read_unlock(); |
| 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 selinux_policy *policy; |
| struct policydb *policydb; |
| struct sidtab *sidtab; |
| struct context *fromcon, usercon; |
| u32 *mysids = NULL, *mysids2, sid; |
| u32 i, j, mynel, maxnel = SIDS_NEL; |
| struct user_datum *user; |
| struct role_datum *role; |
| struct ebitmap_node *rnode, *tnode; |
| int rc; |
| |
| *sids = NULL; |
| *nel = 0; |
| |
| if (!selinux_initialized()) |
| return 0; |
| |
| mysids = kcalloc(maxnel, sizeof(*mysids), GFP_KERNEL); |
| if (!mysids) |
| return -ENOMEM; |
| |
| retry: |
| mynel = 0; |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| policydb = &policy->policydb; |
| sidtab = policy->sidtab; |
| |
| context_init(&usercon); |
| |
| rc = -EINVAL; |
| fromcon = sidtab_search(sidtab, fromsid); |
| if (!fromcon) |
| goto out_unlock; |
| |
| rc = -EINVAL; |
| user = symtab_search(&policydb->p_users, username); |
| if (!user) |
| goto out_unlock; |
| |
| usercon.user = user->value; |
| |
| 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(policydb, fromcon, user, |
| &usercon)) |
| continue; |
| |
| rc = sidtab_context_to_sid(sidtab, &usercon, &sid); |
| if (rc == -ESTALE) { |
| rcu_read_unlock(); |
| goto retry; |
| } |
| 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: |
| rcu_read_unlock(); |
| if (rc || !mynel) { |
| kfree(mysids); |
| return rc; |
| } |
| |
| rc = -ENOMEM; |
| mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL); |
| if (!mysids2) { |
| kfree(mysids); |
| return rc; |
| } |
| 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(); |
| } |
| kfree(mysids); |
| *sids = mysids2; |
| *nel = j; |
| return 0; |
| } |
| |
| /** |
| * __security_genfs_sid - Helper to obtain a SID for a file in a filesystem |
| * @policy: policy |
| * @fstype: filesystem type |
| * @path: path from root of mount |
| * @orig_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. |
| * |
| * WARNING: This function may return -ESTALE, indicating that the caller |
| * must retry the operation after re-acquiring the policy pointer! |
| */ |
| static inline int __security_genfs_sid(struct selinux_policy *policy, |
| const char *fstype, |
| const char *path, |
| u16 orig_sclass, |
| u32 *sid) |
| { |
| struct policydb *policydb = &policy->policydb; |
| struct sidtab *sidtab = policy->sidtab; |
| int len; |
| u16 sclass; |
| struct genfs *genfs; |
| struct ocontext *c; |
| int cmp = 0; |
| |
| while (path[0] == '/' && path[1] == '/') |
| path++; |
| |
| sclass = unmap_class(&policy->map, orig_sclass); |
| *sid = SECINITSID_UNLABELED; |
| |
| for (genfs = policydb->genfs; genfs; genfs = genfs->next) { |
| cmp = strcmp(fstype, genfs->fstype); |
| if (cmp <= 0) |
| break; |
| } |
| |
| if (!genfs || cmp) |
| return -ENOENT; |
| |
| 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) |
| return -ENOENT; |
| |
| return ocontext_to_sid(sidtab, c, 0, sid); |
| } |
| |
| /** |
| * security_genfs_sid - Obtain a SID for a file in a filesystem |
| * @fstype: filesystem type |
| * @path: path from root of mount |
| * @orig_sclass: file security class |
| * @sid: SID for path |
| * |
| * Acquire policy_rwlock before calling __security_genfs_sid() and release |
| * it afterward. |
| */ |
| int security_genfs_sid(const char *fstype, |
| const char *path, |
| u16 orig_sclass, |
| u32 *sid) |
| { |
| struct selinux_policy *policy; |
| int retval; |
| |
| if (!selinux_initialized()) { |
| *sid = SECINITSID_UNLABELED; |
| return 0; |
| } |
| |
| do { |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| retval = __security_genfs_sid(policy, fstype, path, |
| orig_sclass, sid); |
| rcu_read_unlock(); |
| } while (retval == -ESTALE); |
| return retval; |
| } |
| |
| int selinux_policy_genfs_sid(struct selinux_policy *policy, |
| const char *fstype, |
| const char *path, |
| u16 orig_sclass, |
| u32 *sid) |
| { |
| /* no lock required, policy is not yet accessible by other threads */ |
| return __security_genfs_sid(policy, fstype, path, orig_sclass, sid); |
| } |
| |
| /** |
| * security_fs_use - Determine how to handle labeling for a filesystem. |
| * @sb: superblock in question |
| */ |
| int security_fs_use(struct super_block *sb) |
| { |
| struct selinux_policy *policy; |
| struct policydb *policydb; |
| struct sidtab *sidtab; |
| int rc; |
| struct ocontext *c; |
| struct superblock_security_struct *sbsec = selinux_superblock(sb); |
| const char *fstype = sb->s_type->name; |
| |
| if (!selinux_initialized()) { |
| sbsec->behavior = SECURITY_FS_USE_NONE; |
| sbsec->sid = SECINITSID_UNLABELED; |
| return 0; |
| } |
| |
| retry: |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| policydb = &policy->policydb; |
| sidtab = policy->sidtab; |
| |
| c = policydb->ocontexts[OCON_FSUSE]; |
| while (c) { |
| if (strcmp(fstype, c->u.name) == 0) |
| break; |
| c = c->next; |
| } |
| |
| if (c) { |
| sbsec->behavior = c->v.behavior; |
| rc = ocontext_to_sid(sidtab, c, 0, &sbsec->sid); |
| if (rc == -ESTALE) { |
| rcu_read_unlock(); |
| goto retry; |
| } |
| if (rc) |
| goto out; |
| } else { |
| rc = __security_genfs_sid(policy, fstype, "/", |
| SECCLASS_DIR, &sbsec->sid); |
| if (rc == -ESTALE) { |
| rcu_read_unlock(); |
| goto retry; |
| } |
| if (rc) { |
| sbsec->behavior = SECURITY_FS_USE_NONE; |
| rc = 0; |
| } else { |
| sbsec->behavior = SECURITY_FS_USE_GENFS; |
| } |
| } |
| |
| out: |
| rcu_read_unlock(); |
| return rc; |
| } |
| |
| int security_get_bools(struct selinux_policy *policy, |
| u32 *len, char ***names, int **values) |
| { |
| struct policydb *policydb; |
| u32 i; |
| int rc; |
| |
| policydb = &policy->policydb; |
| |
| *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++) { |
| (*values)[i] = policydb->bool_val_to_struct[i]->state; |
| |
| rc = -ENOMEM; |
| (*names)[i] = kstrdup(sym_name(policydb, SYM_BOOLS, i), |
| GFP_ATOMIC); |
| if (!(*names)[i]) |
| goto err; |
| } |
| rc = 0; |
| out: |
| return rc; |
| err: |
| if (*names) { |
| for (i = 0; i < *len; i++) |
| kfree((*names)[i]); |
| kfree(*names); |
| } |
| kfree(*values); |
| *len = 0; |
| *names = NULL; |
| *values = NULL; |
| goto out; |
| } |
| |
| |
| int security_set_bools(u32 len, int *values) |
| { |
| struct selinux_state *state = &selinux_state; |
| struct selinux_policy *newpolicy, *oldpolicy; |
| int rc; |
| u32 i, seqno = 0; |
| |
| if (!selinux_initialized()) |
| return -EINVAL; |
| |
| oldpolicy = rcu_dereference_protected(state->policy, |
| lockdep_is_held(&state->policy_mutex)); |
| |
| /* Consistency check on number of booleans, should never fail */ |
| if (WARN_ON(len != oldpolicy->policydb.p_bools.nprim)) |
| return -EINVAL; |
| |
| newpolicy = kmemdup(oldpolicy, sizeof(*newpolicy), GFP_KERNEL); |
| if (!newpolicy) |
| return -ENOMEM; |
| |
| /* |
| * Deep copy only the parts of the policydb that might be |
| * modified as a result of changing booleans. |
| */ |
| rc = cond_policydb_dup(&newpolicy->policydb, &oldpolicy->policydb); |
| if (rc) { |
| kfree(newpolicy); |
| return -ENOMEM; |
| } |
| |
| /* Update the boolean states in the copy */ |
| for (i = 0; i < len; i++) { |
| int new_state = !!values[i]; |
| int old_state = newpolicy->policydb.bool_val_to_struct[i]->state; |
| |
| if (new_state != old_state) { |
| audit_log(audit_context(), GFP_ATOMIC, |
| AUDIT_MAC_CONFIG_CHANGE, |
| "bool=%s val=%d old_val=%d auid=%u ses=%u", |
| sym_name(&newpolicy->policydb, SYM_BOOLS, i), |
| new_state, |
| old_state, |
| from_kuid(&init_user_ns, audit_get_loginuid(current)), |
| audit_get_sessionid(current)); |
| newpolicy->policydb.bool_val_to_struct[i]->state = new_state; |
| } |
| } |
| |
| /* Re-evaluate the conditional rules in the copy */ |
| evaluate_cond_nodes(&newpolicy->policydb); |
| |
| /* Set latest granting seqno for new policy */ |
| newpolicy->latest_granting = oldpolicy->latest_granting + 1; |
| seqno = newpolicy->latest_granting; |
| |
| /* Install the new policy */ |
| rcu_assign_pointer(state->policy, newpolicy); |
| |
| /* |
| * Free the conditional portions of the old policydb |
| * that were copied for the new policy, and the oldpolicy |
| * structure itself but not what it references. |
| */ |
| synchronize_rcu(); |
| selinux_policy_cond_free(oldpolicy); |
| |
| /* Notify others of the policy change */ |
| selinux_notify_policy_change(seqno); |
| return 0; |
| } |
| |
| int security_get_bool_value(u32 index) |
| { |
| struct selinux_policy *policy; |
| struct policydb *policydb; |
| int rc; |
| u32 len; |
| |
| if (!selinux_initialized()) |
| return 0; |
| |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| policydb = &policy->policydb; |
| |
| rc = -EFAULT; |
| len = policydb->p_bools.nprim; |
| if (index >= len) |
| goto out; |
| |
| rc = policydb->bool_val_to_struct[index]->state; |
| out: |
| rcu_read_unlock(); |
| return rc; |
| } |
| |
| static int security_preserve_bools(struct selinux_policy *oldpolicy, |
| struct selinux_policy *newpolicy) |
| { |
| int rc, *bvalues = NULL; |
| char **bnames = NULL; |
| struct cond_bool_datum *booldatum; |
| u32 i, nbools = 0; |
| |
| rc = security_get_bools(oldpolicy, &nbools, &bnames, &bvalues); |
| if (rc) |
| goto out; |
| for (i = 0; i < nbools; i++) { |
| booldatum = symtab_search(&newpolicy->policydb.p_bools, |
| bnames[i]); |
| if (booldatum) |
| booldatum->state = bvalues[i]; |
| } |
| evaluate_cond_nodes(&newpolicy->policydb); |
| |
| 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 selinux_policy *policy; |
| struct policydb *policydb; |
| struct sidtab *sidtab; |
| struct context *context1; |
| struct context *context2; |
| struct context newcon; |
| char *s; |
| u32 len; |
| int rc; |
| |
| if (!selinux_initialized()) { |
| *new_sid = sid; |
| return 0; |
| } |
| |
| retry: |
| rc = 0; |
| context_init(&newcon); |
| |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| policydb = &policy->policydb; |
| sidtab = policy->sidtab; |
| |
| if (!policydb->mls_enabled) { |
| *new_sid = sid; |
| goto out_unlock; |
| } |
| |
| rc = -EINVAL; |
| context1 = sidtab_search(sidtab, sid); |
| if (!context1) { |
| pr_err("SELinux: %s: unrecognized SID %d\n", |
| __func__, sid); |
| goto out_unlock; |
| } |
| |
| rc = -EINVAL; |
| context2 = sidtab_search(sidtab, mls_sid); |
| if (!context2) { |
| pr_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(policydb, |
| &newcon); |
| if (rc) { |
| if (!context_struct_to_string(policydb, &newcon, &s, |
| &len)) { |
| struct audit_buffer *ab; |
| |
| ab = audit_log_start(audit_context(), |
| GFP_ATOMIC, |
| AUDIT_SELINUX_ERR); |
| audit_log_format(ab, |
| "op=security_sid_mls_copy invalid_context="); |
| /* don't record NUL with untrusted strings */ |
| audit_log_n_untrustedstring(ab, s, len - 1); |
| audit_log_end(ab); |
| kfree(s); |
| } |
| goto out_unlock; |
| } |
| } |
| rc = sidtab_context_to_sid(sidtab, &newcon, new_sid); |
| if (rc == -ESTALE) { |
| rcu_read_unlock(); |
| context_destroy(&newcon); |
| goto retry; |
| } |
| out_unlock: |
| rcu_read_unlock(); |
| context_destroy(&newcon); |
| 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 |
| * @peer_sid: network peer 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) |
| { |
| struct selinux_policy *policy; |
| struct policydb *policydb; |
| struct sidtab *sidtab; |
| 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; |
| } |
| |
| if (!selinux_initialized()) |
| return 0; |
| |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| policydb = &policy->policydb; |
| sidtab = policy->sidtab; |
| |
| /* |
| * We don't need to check 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 state->initialized was true. |
| */ |
| if (!policydb->mls_enabled) { |
| rc = 0; |
| goto out; |
| } |
| |
| rc = -EINVAL; |
| nlbl_ctx = sidtab_search(sidtab, nlbl_sid); |
| if (!nlbl_ctx) { |
| pr_err("SELinux: %s: unrecognized SID %d\n", |
| __func__, nlbl_sid); |
| goto out; |
| } |
| rc = -EINVAL; |
| xfrm_ctx = sidtab_search(sidtab, xfrm_sid); |
| if (!xfrm_ctx) { |
| pr_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: |
| rcu_read_unlock(); |
| 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(struct selinux_policy *policy, |
| char ***classes, int *nclasses) |
| { |
| struct policydb *policydb; |
| int rc; |
| |
| policydb = &policy->policydb; |
| |
| 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: |
| 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(struct selinux_policy *policy, |
| char *class, char ***perms, int *nperms) |
| { |
| struct policydb *policydb; |
| int rc, i; |
| struct class_datum *match; |
| |
| policydb = &policy->policydb; |
| |
| rc = -EINVAL; |
| match = symtab_search(&policydb->p_classes, class); |
| if (!match) { |
| pr_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: |
| return rc; |
| |
| err: |
| for (i = 0; i < *nperms; i++) |
| kfree((*perms)[i]); |
| kfree(*perms); |
| return rc; |
| } |
| |
| int security_get_reject_unknown(void) |
| { |
| struct selinux_policy *policy; |
| int value; |
| |
| if (!selinux_initialized()) |
| return 0; |
| |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| value = policy->policydb.reject_unknown; |
| rcu_read_unlock(); |
| return value; |
| } |
| |
| int security_get_allow_unknown(void) |
| { |
| struct selinux_policy *policy; |
| int value; |
| |
| if (!selinux_initialized()) |
| return 0; |
| |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| value = policy->policydb.allow_unknown; |
| rcu_read_unlock(); |
| return value; |
| } |
| |
| /** |
| * 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) |
| { |
| struct selinux_policy *policy; |
| int rc; |
| |
| if (!selinux_initialized()) |
| return 0; |
| |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| rc = ebitmap_get_bit(&policy->policydb.policycaps, req_cap); |
| rcu_read_unlock(); |
| |
| 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_state *state = &selinux_state; |
| struct selinux_policy *policy; |
| struct policydb *policydb; |
| 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 (!selinux_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); |
| |
| rcu_read_lock(); |
| policy = rcu_dereference(state->policy); |
| policydb = &policy->policydb; |
| |
| tmprule->au_seqno = policy->latest_granting; |
| |
| switch (field) { |
| case AUDIT_SUBJ_USER: |
| case AUDIT_OBJ_USER: |
| rc = -EINVAL; |
| userdatum = symtab_search(&policydb->p_users, rulestr); |
| if (!userdatum) |
| goto out; |
| tmprule->au_ctxt.user = userdatum->value; |
| break; |
| case AUDIT_SUBJ_ROLE: |
| case AUDIT_OBJ_ROLE: |
| rc = -EINVAL; |
| roledatum = symtab_search(&policydb->p_roles, rulestr); |
| if (!roledatum) |
| goto out; |
| tmprule->au_ctxt.role = roledatum->value; |
| break; |
| case AUDIT_SUBJ_TYPE: |
| case AUDIT_OBJ_TYPE: |
| rc = -EINVAL; |
| typedatum = symtab_search(&policydb->p_types, 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(policydb, rulestr, &tmprule->au_ctxt, |
| GFP_ATOMIC); |
| if (rc) |
| goto out; |
| break; |
| } |
| rc = 0; |
| out: |
| rcu_read_unlock(); |
| |
| 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 selinux_state *state = &selinux_state; |
| struct selinux_policy *policy; |
| struct context *ctxt; |
| struct mls_level *level; |
| struct selinux_audit_rule *rule = vrule; |
| int match = 0; |
| |
| if (unlikely(!rule)) { |
| WARN_ONCE(1, "selinux_audit_rule_match: missing rule\n"); |
| return -ENOENT; |
| } |
| |
| if (!selinux_initialized()) |
| return 0; |
| |
| rcu_read_lock(); |
| |
| policy = rcu_dereference(state->policy); |
| |
| if (rule->au_seqno < policy->latest_granting) { |
| match = -ESTALE; |
| goto out; |
| } |
| |
| ctxt = sidtab_search(policy->sidtab, sid); |
| if (unlikely(!ctxt)) { |
| WARN_ONCE(1, "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: |
| rcu_read_unlock(); |
| return match; |
| } |
| |
| static int aurule_avc_callback(u32 event) |
| { |
| if (event == AVC_CALLBACK_RESET) |
| return audit_update_lsm_rules(); |
| return 0; |
| } |
| |
| static int __init aurule_init(void) |
| { |
| int err; |
| |
| err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET); |
| 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) |
| { |
| struct selinux_policy *policy; |
| struct policydb *policydb; |
| struct sidtab *sidtab; |
| int rc; |
| struct context *ctx; |
| struct context ctx_new; |
| |
| if (!selinux_initialized()) { |
| *sid = SECSID_NULL; |
| return 0; |
| } |
| |
| retry: |
| rc = 0; |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| policydb = &policy->policydb; |
| sidtab = policy->sidtab; |
| |
| 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(policydb, &ctx_new, secattr); |
| if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { |
| rc = mls_import_netlbl_cat(policydb, &ctx_new, secattr); |
| if (rc) |
| goto out; |
| } |
| rc = -EIDRM; |
| if (!mls_context_isvalid(policydb, &ctx_new)) { |
| ebitmap_destroy(&ctx_new.range.level[0].cat); |
| goto out; |
| } |
| |
| rc = sidtab_context_to_sid(sidtab, &ctx_new, sid); |
| ebitmap_destroy(&ctx_new.range.level[0].cat); |
| if (rc == -ESTALE) { |
| rcu_read_unlock(); |
| goto retry; |
| } |
| if (rc) |
| goto out; |
| |
| security_netlbl_cache_add(secattr, *sid); |
| } else |
| *sid = SECSID_NULL; |
| |
| out: |
| rcu_read_unlock(); |
| 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) |
| { |
| struct selinux_policy *policy; |
| struct policydb *policydb; |
| int rc; |
| struct context *ctx; |
| |
| if (!selinux_initialized()) |
| return 0; |
| |
| rcu_read_lock(); |
| policy = rcu_dereference(selinux_state.policy); |
| policydb = &policy->policydb; |
| |
| rc = -ENOENT; |
| ctx = sidtab_search(policy->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(policydb, ctx, secattr); |
| rc = mls_export_netlbl_cat(policydb, ctx, secattr); |
| out: |
| rcu_read_unlock(); |
| return rc; |
| } |
| #endif /* CONFIG_NETLABEL */ |
| |
| /** |
| * __security_read_policy - read the policy. |
| * @policy: SELinux policy |
| * @data: binary policy data |
| * @len: length of data in bytes |
| * |
| */ |
| static int __security_read_policy(struct selinux_policy *policy, |
| void *data, size_t *len) |
| { |
| int rc; |
| struct policy_file fp; |
| |
| fp.data = data; |
| fp.len = *len; |
| |
| rc = policydb_write(&policy->policydb, &fp); |
| if (rc) |
| return rc; |
| |
| *len = (unsigned long)fp.data - (unsigned long)data; |
| return 0; |
| } |
| |
| /** |
| * 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) |
| { |
| struct selinux_state *state = &selinux_state; |
| struct selinux_policy *policy; |
| |
| policy = rcu_dereference_protected( |
| state->policy, lockdep_is_held(&state->policy_mutex)); |
| if (!policy) |
| return -EINVAL; |
| |
| *len = policy->policydb.len; |
| *data = vmalloc_user(*len); |
| if (!*data) |
| return -ENOMEM; |
| |
| return __security_read_policy(policy, *data, len); |
| } |
| |
| /** |
| * security_read_state_kernel - read the policy. |
| * @data: binary policy data |
| * @len: length of data in bytes |
| * |
| * Allocates kernel memory for reading SELinux policy. |
| * This function is for internal use only and should not |
| * be used for returning data to user space. |
| * |
| * This function must be called with policy_mutex held. |
| */ |
| int security_read_state_kernel(void **data, size_t *len) |
| { |
| int err; |
| struct selinux_state *state = &selinux_state; |
| struct selinux_policy *policy; |
| |
| policy = rcu_dereference_protected( |
| state->policy, lockdep_is_held(&state->policy_mutex)); |
| if (!policy) |
| return -EINVAL; |
| |
| *len = policy->policydb.len; |
| *data = vmalloc(*len); |
| if (!*data) |
| return -ENOMEM; |
| |
| err = __security_read_policy(policy, *data, len); |
| if (err) { |
| vfree(*data); |
| *data = NULL; |
| *len = 0; |
| } |
| return err; |
| } |