diff options
Diffstat (limited to 'security/selinux/ss/conditional.c')
| -rw-r--r-- | security/selinux/ss/conditional.c | 271 |
1 files changed, 209 insertions, 62 deletions
diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c index da94a1b4bfda..1bebfcb9c6a1 100644 --- a/security/selinux/ss/conditional.c +++ b/security/selinux/ss/conditional.c @@ -1,8 +1,7 @@ -// SPDX-License-Identifier: GPL-2.0-only +/* SPDX-License-Identifier: GPL-2.0-only */ /* Authors: Karl MacMillan <kmacmillan@tresys.com> * Frank Mayer <mayerf@tresys.com> - * - * Copyright (C) 2003 - 2004 Tresys Technology, LLC + * Copyright (C) 2003 - 2004 Tresys Technology, LLC */ #include <linux/kernel.h> @@ -27,6 +26,9 @@ static int cond_evaluate_expr(struct policydb *p, struct cond_expr *expr) int s[COND_EXPR_MAXDEPTH]; int sp = -1; + if (expr->len == 0) + return -1; + for (i = 0; i < expr->len; i++) { struct cond_expr_node *node = &expr->nodes[i]; @@ -35,7 +37,7 @@ static int cond_evaluate_expr(struct policydb *p, struct cond_expr *expr) if (sp == (COND_EXPR_MAXDEPTH - 1)) return -1; sp++; - s[sp] = p->bool_val_to_struct[node->bool - 1]->state; + s[sp] = p->bool_val_to_struct[node->boolean - 1]->state; break; case COND_NOT: if (sp < 0) @@ -149,6 +151,8 @@ static void cond_list_destroy(struct policydb *p) for (i = 0; i < p->cond_list_len; i++) cond_node_destroy(&p->cond_list[i]); kfree(p->cond_list); + p->cond_list = NULL; + p->cond_list_len = 0; } void cond_policydb_destroy(struct policydb *p) @@ -161,11 +165,13 @@ void cond_policydb_destroy(struct policydb *p) int cond_init_bool_indexes(struct policydb *p) { kfree(p->bool_val_to_struct); - p->bool_val_to_struct = kmalloc_array(p->p_bools.nprim, - sizeof(*p->bool_val_to_struct), - GFP_KERNEL); + p->bool_val_to_struct = kmalloc_array( + p->p_bools.nprim, sizeof(*p->bool_val_to_struct), GFP_KERNEL); if (!p->bool_val_to_struct) return -ENOMEM; + + avtab_hash_eval(&p->te_cond_avtab, "conditional_rules"); + return 0; } @@ -200,7 +206,7 @@ static int bool_isvalid(struct cond_bool_datum *b) return 1; } -int cond_read_bool(struct policydb *p, struct hashtab *h, void *fp) +int cond_read_bool(struct policydb *p, struct symtab *s, struct policy_file *fp) { char *key = NULL; struct cond_bool_datum *booldatum; @@ -212,7 +218,7 @@ int cond_read_bool(struct policydb *p, struct hashtab *h, void *fp) if (!booldatum) return -ENOMEM; - rc = next_entry(buf, fp, sizeof buf); + rc = next_entry(buf, fp, sizeof(buf)); if (rc) goto err; @@ -224,18 +230,12 @@ int cond_read_bool(struct policydb *p, struct hashtab *h, void *fp) goto err; len = le32_to_cpu(buf[2]); - if (((len == 0) || (len == (u32)-1))) - goto err; - rc = -ENOMEM; - key = kmalloc(len + 1, GFP_KERNEL); - if (!key) - goto err; - rc = next_entry(key, fp, len); + rc = str_read(&key, GFP_KERNEL, fp, len); if (rc) goto err; - key[len] = '\0'; - rc = hashtab_insert(h, key, booldatum); + + rc = symtab_insert(s, key, booldatum); if (rc) goto err; @@ -251,7 +251,8 @@ struct cond_insertf_data { struct cond_av_list *other; }; -static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum *d, void *ptr) +static int cond_insertf(struct avtab *a, const struct avtab_key *k, + const struct avtab_datum *d, void *ptr) { struct cond_insertf_data *data = ptr; struct policydb *p = data->p; @@ -266,7 +267,7 @@ static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum * cond_te_avtab. */ if (k->specified & AVTAB_TYPE) { - if (avtab_search(&p->te_avtab, k)) { + if (avtab_search_node(&p->te_avtab, k)) { pr_err("SELinux: type rule already exists outside of a conditional.\n"); return -EINVAL; } @@ -281,7 +282,8 @@ static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum if (other) { node_ptr = avtab_search_node(&p->te_cond_avtab, k); if (node_ptr) { - if (avtab_search_node_next(node_ptr, k->specified)) { + if (avtab_search_node_next(node_ptr, + k->specified)) { pr_err("SELinux: too many conflicting type rules.\n"); return -EINVAL; } @@ -298,7 +300,7 @@ static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum } } } else { - if (avtab_search(&p->te_cond_avtab, k)) { + if (avtab_search_node(&p->te_cond_avtab, k)) { pr_err("SELinux: conflicting type rules when adding type rule for true.\n"); return -EINVAL; } @@ -315,7 +317,7 @@ static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum return 0; } -static int cond_read_av_list(struct policydb *p, void *fp, +static int cond_read_av_list(struct policydb *p, struct policy_file *fp, struct cond_av_list *list, struct cond_av_list *other) { @@ -341,7 +343,7 @@ static int cond_read_av_list(struct policydb *p, void *fp, for (i = 0; i < len; i++) { data.dst = &list->nodes[i]; rc = avtab_read_item(&p->te_cond_avtab, fp, p, cond_insertf, - &data); + &data, true); if (rc) { kfree(list->nodes); list->nodes = NULL; @@ -360,14 +362,14 @@ static int expr_node_isvalid(struct policydb *p, struct cond_expr_node *expr) return 0; } - if (expr->bool > p->p_bools.nprim) { + if (expr->boolean > p->p_bools.nprim) { pr_err("SELinux: conditional expressions uses unknown bool.\n"); return 0; } return 1; } -static int cond_read_node(struct policydb *p, struct cond_node *node, void *fp) +static int cond_read_node(struct policydb *p, struct cond_node *node, struct policy_file *fp) { __le32 buf[2]; u32 i, len; @@ -392,36 +394,28 @@ static int cond_read_node(struct policydb *p, struct cond_node *node, void *fp) rc = next_entry(buf, fp, sizeof(u32) * 2); if (rc) - goto err; + return rc; expr->expr_type = le32_to_cpu(buf[0]); - expr->bool = le32_to_cpu(buf[1]); + expr->boolean = le32_to_cpu(buf[1]); - if (!expr_node_isvalid(p, expr)) { - rc = -EINVAL; - goto err; - } + if (!expr_node_isvalid(p, expr)) + return -EINVAL; } rc = cond_read_av_list(p, fp, &node->true_list, NULL); if (rc) - goto err; - rc = cond_read_av_list(p, fp, &node->false_list, &node->true_list); - if (rc) - goto err; - return 0; -err: - cond_node_destroy(node); - return rc; + return rc; + return cond_read_av_list(p, fp, &node->false_list, &node->true_list); } -int cond_read_list(struct policydb *p, void *fp) +int cond_read_list(struct policydb *p, struct policy_file *fp) { __le32 buf[1]; u32 i, len; int rc; - rc = next_entry(buf, fp, sizeof buf); + rc = next_entry(buf, fp, sizeof(buf)); if (rc) return rc; @@ -445,7 +439,6 @@ int cond_read_list(struct policydb *p, void *fp) return 0; err: cond_list_destroy(p); - p->cond_list = NULL; return rc; } @@ -454,7 +447,7 @@ int cond_write_bool(void *vkey, void *datum, void *ptr) char *key = vkey; struct cond_bool_datum *booldatum = datum; struct policy_data *pd = ptr; - void *fp = pd->fp; + struct policy_file *fp = pd->fp; __le32 buf[3]; u32 len; int rc; @@ -481,8 +474,8 @@ int cond_write_bool(void *vkey, void *datum, void *ptr) * the conditional. This means that the avtab with the conditional * rules will not be saved but will be rebuilt on policy load. */ -static int cond_write_av_list(struct policydb *p, - struct cond_av_list *list, struct policy_file *fp) +static int cond_write_av_list(struct policydb *p, struct cond_av_list *list, + struct policy_file *fp) { __le32 buf[1]; u32 i; @@ -503,7 +496,7 @@ static int cond_write_av_list(struct policydb *p, } static int cond_write_node(struct policydb *p, struct cond_node *node, - struct policy_file *fp) + struct policy_file *fp) { __le32 buf[2]; int rc; @@ -521,7 +514,7 @@ static int cond_write_node(struct policydb *p, struct cond_node *node, for (i = 0; i < node->expr.len; i++) { buf[0] = cpu_to_le32(node->expr.nodes[i].expr_type); - buf[1] = cpu_to_le32(node->expr.nodes[i].bool); + buf[1] = cpu_to_le32(node->expr.nodes[i].boolean); rc = put_entry(buf, sizeof(u32), 2, fp); if (rc) return rc; @@ -537,7 +530,7 @@ static int cond_write_node(struct policydb *p, struct cond_node *node, return 0; } -int cond_write_list(struct policydb *p, void *fp) +int cond_write_list(struct policydb *p, struct policy_file *fp) { u32 i; __le32 buf[1]; @@ -558,7 +551,7 @@ int cond_write_list(struct policydb *p, void *fp) } void cond_compute_xperms(struct avtab *ctab, struct avtab_key *key, - struct extended_perms_decision *xpermd) + struct extended_perms_decision *xpermd) { struct avtab_node *node; @@ -566,18 +559,16 @@ void cond_compute_xperms(struct avtab *ctab, struct avtab_key *key, return; for (node = avtab_search_node(ctab, key); node; - node = avtab_search_node_next(node, key->specified)) { + node = avtab_search_node_next(node, key->specified)) { if (node->key.specified & AVTAB_ENABLED) services_compute_xperms_decision(xpermd, node); } - return; - } /* Determine whether additional permissions are granted by the conditional * av table, and if so, add them to the result */ void cond_compute_av(struct avtab *ctab, struct avtab_key *key, - struct av_decision *avd, struct extended_perms *xperms) + struct av_decision *avd, struct extended_perms *xperms) { struct avtab_node *node; @@ -585,23 +576,179 @@ void cond_compute_av(struct avtab *ctab, struct avtab_key *key, return; for (node = avtab_search_node(ctab, key); node; - node = avtab_search_node_next(node, key->specified)) { - if ((u16)(AVTAB_ALLOWED|AVTAB_ENABLED) == - (node->key.specified & (AVTAB_ALLOWED|AVTAB_ENABLED))) + node = avtab_search_node_next(node, key->specified)) { + if ((u16)(AVTAB_ALLOWED | AVTAB_ENABLED) == + (node->key.specified & (AVTAB_ALLOWED | AVTAB_ENABLED))) avd->allowed |= node->datum.u.data; - if ((u16)(AVTAB_AUDITDENY|AVTAB_ENABLED) == - (node->key.specified & (AVTAB_AUDITDENY|AVTAB_ENABLED))) + if ((u16)(AVTAB_AUDITDENY | AVTAB_ENABLED) == + (node->key.specified & (AVTAB_AUDITDENY | AVTAB_ENABLED))) /* Since a '0' in an auditdeny mask represents a * permission we do NOT want to audit (dontaudit), we use * the '&' operand to ensure that all '0's in the mask * are retained (much unlike the allow and auditallow cases). */ avd->auditdeny &= node->datum.u.data; - if ((u16)(AVTAB_AUDITALLOW|AVTAB_ENABLED) == - (node->key.specified & (AVTAB_AUDITALLOW|AVTAB_ENABLED))) + if ((u16)(AVTAB_AUDITALLOW | AVTAB_ENABLED) == + (node->key.specified & (AVTAB_AUDITALLOW | AVTAB_ENABLED))) avd->auditallow |= node->datum.u.data; if (xperms && (node->key.specified & AVTAB_ENABLED) && - (node->key.specified & AVTAB_XPERMS)) + (node->key.specified & AVTAB_XPERMS)) services_compute_xperms_drivers(xperms, node); } } + +static int cond_dup_av_list(struct cond_av_list *new, + const struct cond_av_list *orig, + struct avtab *avtab) +{ + u32 i; + + memset(new, 0, sizeof(*new)); + + new->nodes = kcalloc(orig->len, sizeof(*new->nodes), GFP_KERNEL); + if (!new->nodes) + return -ENOMEM; + + for (i = 0; i < orig->len; i++) { + new->nodes[i] = avtab_insert_nonunique( + avtab, &orig->nodes[i]->key, &orig->nodes[i]->datum); + if (!new->nodes[i]) + return -ENOMEM; + new->len++; + } + + return 0; +} + +static int duplicate_policydb_cond_list(struct policydb *newp, + const struct policydb *origp) +{ + int rc; + u32 i; + + rc = avtab_alloc_dup(&newp->te_cond_avtab, &origp->te_cond_avtab); + if (rc) + return rc; + + newp->cond_list_len = 0; + newp->cond_list = kcalloc(origp->cond_list_len, + sizeof(*newp->cond_list), GFP_KERNEL); + if (!newp->cond_list) + goto error; + + for (i = 0; i < origp->cond_list_len; i++) { + struct cond_node *newn = &newp->cond_list[i]; + const struct cond_node *orign = &origp->cond_list[i]; + + newp->cond_list_len++; + + newn->cur_state = orign->cur_state; + newn->expr.nodes = + kmemdup(orign->expr.nodes, + orign->expr.len * sizeof(*orign->expr.nodes), + GFP_KERNEL); + if (!newn->expr.nodes) + goto error; + + newn->expr.len = orign->expr.len; + + rc = cond_dup_av_list(&newn->true_list, &orign->true_list, + &newp->te_cond_avtab); + if (rc) + goto error; + + rc = cond_dup_av_list(&newn->false_list, &orign->false_list, + &newp->te_cond_avtab); + if (rc) + goto error; + } + + return 0; + +error: + avtab_destroy(&newp->te_cond_avtab); + cond_list_destroy(newp); + return -ENOMEM; +} + +static int cond_bools_destroy(void *key, void *datum, void *args) +{ + /* key was not copied so no need to free here */ + kfree(datum); + return 0; +} + +static int cond_bools_copy(struct hashtab_node *new, + const struct hashtab_node *orig, void *args) +{ + struct cond_bool_datum *datum; + + datum = kmemdup(orig->datum, sizeof(struct cond_bool_datum), + GFP_KERNEL); + if (!datum) + return -ENOMEM; + + new->key = orig->key; /* No need to copy, never modified */ + new->datum = datum; + return 0; +} + +static int cond_bools_index(void *key, void *datum, void *args) +{ + struct cond_bool_datum *booldatum, **cond_bool_array; + + booldatum = datum; + cond_bool_array = args; + cond_bool_array[booldatum->value - 1] = booldatum; + + return 0; +} + +static int duplicate_policydb_bools(struct policydb *newdb, + const struct policydb *orig) +{ + struct cond_bool_datum **cond_bool_array; + int rc; + + cond_bool_array = kmalloc_array(orig->p_bools.nprim, + sizeof(*orig->bool_val_to_struct), + GFP_KERNEL); + if (!cond_bool_array) + return -ENOMEM; + + rc = hashtab_duplicate(&newdb->p_bools.table, &orig->p_bools.table, + cond_bools_copy, cond_bools_destroy, NULL); + if (rc) { + kfree(cond_bool_array); + return -ENOMEM; + } + + hashtab_map(&newdb->p_bools.table, cond_bools_index, cond_bool_array); + newdb->bool_val_to_struct = cond_bool_array; + + newdb->p_bools.nprim = orig->p_bools.nprim; + + return 0; +} + +void cond_policydb_destroy_dup(struct policydb *p) +{ + hashtab_map(&p->p_bools.table, cond_bools_destroy, NULL); + hashtab_destroy(&p->p_bools.table); + cond_policydb_destroy(p); +} + +int cond_policydb_dup(struct policydb *new, const struct policydb *orig) +{ + cond_policydb_init(new); + + if (duplicate_policydb_bools(new, orig)) + return -ENOMEM; + + if (duplicate_policydb_cond_list(new, orig)) { + cond_policydb_destroy_dup(new); + return -ENOMEM; + } + + return 0; +} |
