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-rw-r--r--ANDROID_3.4.5/security/selinux/ss/conditional.c648
1 files changed, 0 insertions, 648 deletions
diff --git a/ANDROID_3.4.5/security/selinux/ss/conditional.c b/ANDROID_3.4.5/security/selinux/ss/conditional.c
deleted file mode 100644
index 377d148e..00000000
--- a/ANDROID_3.4.5/security/selinux/ss/conditional.c
+++ /dev/null
@@ -1,648 +0,0 @@
-/* Authors: Karl MacMillan <kmacmillan@tresys.com>
- * Frank Mayer <mayerf@tresys.com>
- *
- * Copyright (C) 2003 - 2004 Tresys Technology, LLC
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, version 2.
- */
-
-#include <linux/kernel.h>
-#include <linux/errno.h>
-#include <linux/string.h>
-#include <linux/spinlock.h>
-#include <linux/slab.h>
-
-#include "security.h"
-#include "conditional.h"
-
-/*
- * cond_evaluate_expr evaluates a conditional expr
- * in reverse polish notation. It returns true (1), false (0),
- * or undefined (-1). Undefined occurs when the expression
- * exceeds the stack depth of COND_EXPR_MAXDEPTH.
- */
-static int cond_evaluate_expr(struct policydb *p, struct cond_expr *expr)
-{
-
- struct cond_expr *cur;
- int s[COND_EXPR_MAXDEPTH];
- int sp = -1;
-
- for (cur = expr; cur; cur = cur->next) {
- switch (cur->expr_type) {
- case COND_BOOL:
- if (sp == (COND_EXPR_MAXDEPTH - 1))
- return -1;
- sp++;
- s[sp] = p->bool_val_to_struct[cur->bool - 1]->state;
- break;
- case COND_NOT:
- if (sp < 0)
- return -1;
- s[sp] = !s[sp];
- break;
- case COND_OR:
- if (sp < 1)
- return -1;
- sp--;
- s[sp] |= s[sp + 1];
- break;
- case COND_AND:
- if (sp < 1)
- return -1;
- sp--;
- s[sp] &= s[sp + 1];
- break;
- case COND_XOR:
- if (sp < 1)
- return -1;
- sp--;
- s[sp] ^= s[sp + 1];
- break;
- case COND_EQ:
- if (sp < 1)
- return -1;
- sp--;
- s[sp] = (s[sp] == s[sp + 1]);
- break;
- case COND_NEQ:
- if (sp < 1)
- return -1;
- sp--;
- s[sp] = (s[sp] != s[sp + 1]);
- break;
- default:
- return -1;
- }
- }
- return s[0];
-}
-
-/*
- * evaluate_cond_node evaluates the conditional stored in
- * a struct cond_node and if the result is different than the
- * current state of the node it sets the rules in the true/false
- * list appropriately. If the result of the expression is undefined
- * all of the rules are disabled for safety.
- */
-int evaluate_cond_node(struct policydb *p, struct cond_node *node)
-{
- int new_state;
- struct cond_av_list *cur;
-
- new_state = cond_evaluate_expr(p, node->expr);
- if (new_state != node->cur_state) {
- node->cur_state = new_state;
- if (new_state == -1)
- printk(KERN_ERR "SELinux: expression result was undefined - disabling all rules.\n");
- /* turn the rules on or off */
- for (cur = node->true_list; cur; cur = cur->next) {
- if (new_state <= 0)
- cur->node->key.specified &= ~AVTAB_ENABLED;
- else
- cur->node->key.specified |= AVTAB_ENABLED;
- }
-
- for (cur = node->false_list; cur; cur = cur->next) {
- /* -1 or 1 */
- if (new_state)
- cur->node->key.specified &= ~AVTAB_ENABLED;
- else
- cur->node->key.specified |= AVTAB_ENABLED;
- }
- }
- return 0;
-}
-
-int cond_policydb_init(struct policydb *p)
-{
- int rc;
-
- p->bool_val_to_struct = NULL;
- p->cond_list = NULL;
-
- rc = avtab_init(&p->te_cond_avtab);
- if (rc)
- return rc;
-
- return 0;
-}
-
-static void cond_av_list_destroy(struct cond_av_list *list)
-{
- struct cond_av_list *cur, *next;
- for (cur = list; cur; cur = next) {
- next = cur->next;
- /* the avtab_ptr_t node is destroy by the avtab */
- kfree(cur);
- }
-}
-
-static void cond_node_destroy(struct cond_node *node)
-{
- struct cond_expr *cur_expr, *next_expr;
-
- for (cur_expr = node->expr; cur_expr; cur_expr = next_expr) {
- next_expr = cur_expr->next;
- kfree(cur_expr);
- }
- cond_av_list_destroy(node->true_list);
- cond_av_list_destroy(node->false_list);
- kfree(node);
-}
-
-static void cond_list_destroy(struct cond_node *list)
-{
- struct cond_node *next, *cur;
-
- if (list == NULL)
- return;
-
- for (cur = list; cur; cur = next) {
- next = cur->next;
- cond_node_destroy(cur);
- }
-}
-
-void cond_policydb_destroy(struct policydb *p)
-{
- kfree(p->bool_val_to_struct);
- avtab_destroy(&p->te_cond_avtab);
- cond_list_destroy(p->cond_list);
-}
-
-int cond_init_bool_indexes(struct policydb *p)
-{
- kfree(p->bool_val_to_struct);
- p->bool_val_to_struct =
- kmalloc(p->p_bools.nprim * sizeof(struct cond_bool_datum *), GFP_KERNEL);
- if (!p->bool_val_to_struct)
- return -ENOMEM;
- return 0;
-}
-
-int cond_destroy_bool(void *key, void *datum, void *p)
-{
- kfree(key);
- kfree(datum);
- return 0;
-}
-
-int cond_index_bool(void *key, void *datum, void *datap)
-{
- struct policydb *p;
- struct cond_bool_datum *booldatum;
- struct flex_array *fa;
-
- booldatum = datum;
- p = datap;
-
- if (!booldatum->value || booldatum->value > p->p_bools.nprim)
- return -EINVAL;
-
- fa = p->sym_val_to_name[SYM_BOOLS];
- if (flex_array_put_ptr(fa, booldatum->value - 1, key,
- GFP_KERNEL | __GFP_ZERO))
- BUG();
- p->bool_val_to_struct[booldatum->value - 1] = booldatum;
-
- return 0;
-}
-
-static int bool_isvalid(struct cond_bool_datum *b)
-{
- if (!(b->state == 0 || b->state == 1))
- return 0;
- return 1;
-}
-
-int cond_read_bool(struct policydb *p, struct hashtab *h, void *fp)
-{
- char *key = NULL;
- struct cond_bool_datum *booldatum;
- __le32 buf[3];
- u32 len;
- int rc;
-
- booldatum = kzalloc(sizeof(struct cond_bool_datum), GFP_KERNEL);
- if (!booldatum)
- return -ENOMEM;
-
- rc = next_entry(buf, fp, sizeof buf);
- if (rc)
- goto err;
-
- booldatum->value = le32_to_cpu(buf[0]);
- booldatum->state = le32_to_cpu(buf[1]);
-
- rc = -EINVAL;
- if (!bool_isvalid(booldatum))
- goto err;
-
- len = le32_to_cpu(buf[2]);
-
- rc = -ENOMEM;
- key = kmalloc(len + 1, GFP_KERNEL);
- if (!key)
- goto err;
- rc = next_entry(key, fp, len);
- if (rc)
- goto err;
- key[len] = '\0';
- rc = hashtab_insert(h, key, booldatum);
- if (rc)
- goto err;
-
- return 0;
-err:
- cond_destroy_bool(key, booldatum, NULL);
- return rc;
-}
-
-struct cond_insertf_data {
- struct policydb *p;
- struct cond_av_list *other;
- struct cond_av_list *head;
- struct cond_av_list *tail;
-};
-
-static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum *d, void *ptr)
-{
- struct cond_insertf_data *data = ptr;
- struct policydb *p = data->p;
- struct cond_av_list *other = data->other, *list, *cur;
- struct avtab_node *node_ptr;
- u8 found;
- int rc = -EINVAL;
-
- /*
- * For type rules we have to make certain there aren't any
- * conflicting rules by searching the te_avtab and the
- * cond_te_avtab.
- */
- if (k->specified & AVTAB_TYPE) {
- if (avtab_search(&p->te_avtab, k)) {
- printk(KERN_ERR "SELinux: type rule already exists outside of a conditional.\n");
- goto err;
- }
- /*
- * If we are reading the false list other will be a pointer to
- * the true list. We can have duplicate entries if there is only
- * 1 other entry and it is in our true list.
- *
- * If we are reading the true list (other == NULL) there shouldn't
- * be any other entries.
- */
- if (other) {
- node_ptr = avtab_search_node(&p->te_cond_avtab, k);
- if (node_ptr) {
- if (avtab_search_node_next(node_ptr, k->specified)) {
- printk(KERN_ERR "SELinux: too many conflicting type rules.\n");
- goto err;
- }
- found = 0;
- for (cur = other; cur; cur = cur->next) {
- if (cur->node == node_ptr) {
- found = 1;
- break;
- }
- }
- if (!found) {
- printk(KERN_ERR "SELinux: conflicting type rules.\n");
- goto err;
- }
- }
- } else {
- if (avtab_search(&p->te_cond_avtab, k)) {
- printk(KERN_ERR "SELinux: conflicting type rules when adding type rule for true.\n");
- goto err;
- }
- }
- }
-
- node_ptr = avtab_insert_nonunique(&p->te_cond_avtab, k, d);
- if (!node_ptr) {
- printk(KERN_ERR "SELinux: could not insert rule.\n");
- rc = -ENOMEM;
- goto err;
- }
-
- list = kzalloc(sizeof(struct cond_av_list), GFP_KERNEL);
- if (!list) {
- rc = -ENOMEM;
- goto err;
- }
-
- list->node = node_ptr;
- if (!data->head)
- data->head = list;
- else
- data->tail->next = list;
- data->tail = list;
- return 0;
-
-err:
- cond_av_list_destroy(data->head);
- data->head = NULL;
- return rc;
-}
-
-static int cond_read_av_list(struct policydb *p, void *fp, struct cond_av_list **ret_list, struct cond_av_list *other)
-{
- int i, rc;
- __le32 buf[1];
- u32 len;
- struct cond_insertf_data data;
-
- *ret_list = NULL;
-
- len = 0;
- rc = next_entry(buf, fp, sizeof(u32));
- if (rc)
- return rc;
-
- len = le32_to_cpu(buf[0]);
- if (len == 0)
- return 0;
-
- data.p = p;
- data.other = other;
- data.head = NULL;
- data.tail = NULL;
- for (i = 0; i < len; i++) {
- rc = avtab_read_item(&p->te_cond_avtab, fp, p, cond_insertf,
- &data);
- if (rc)
- return rc;
- }
-
- *ret_list = data.head;
- return 0;
-}
-
-static int expr_isvalid(struct policydb *p, struct cond_expr *expr)
-{
- if (expr->expr_type <= 0 || expr->expr_type > COND_LAST) {
- printk(KERN_ERR "SELinux: conditional expressions uses unknown operator.\n");
- return 0;
- }
-
- if (expr->bool > p->p_bools.nprim) {
- printk(KERN_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)
-{
- __le32 buf[2];
- u32 len, i;
- int rc;
- struct cond_expr *expr = NULL, *last = NULL;
-
- rc = next_entry(buf, fp, sizeof(u32));
- if (rc)
- return rc;
-
- node->cur_state = le32_to_cpu(buf[0]);
-
- len = 0;
- rc = next_entry(buf, fp, sizeof(u32));
- if (rc)
- return rc;
-
- /* expr */
- len = le32_to_cpu(buf[0]);
-
- for (i = 0; i < len; i++) {
- rc = next_entry(buf, fp, sizeof(u32) * 2);
- if (rc)
- goto err;
-
- rc = -ENOMEM;
- expr = kzalloc(sizeof(struct cond_expr), GFP_KERNEL);
- if (!expr)
- goto err;
-
- expr->expr_type = le32_to_cpu(buf[0]);
- expr->bool = le32_to_cpu(buf[1]);
-
- if (!expr_isvalid(p, expr)) {
- rc = -EINVAL;
- kfree(expr);
- goto err;
- }
-
- if (i == 0)
- node->expr = expr;
- else
- last->next = expr;
- last = expr;
- }
-
- 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;
-}
-
-int cond_read_list(struct policydb *p, void *fp)
-{
- struct cond_node *node, *last = NULL;
- __le32 buf[1];
- u32 i, len;
- int rc;
-
- rc = next_entry(buf, fp, sizeof buf);
- if (rc)
- return rc;
-
- len = le32_to_cpu(buf[0]);
-
- rc = avtab_alloc(&(p->te_cond_avtab), p->te_avtab.nel);
- if (rc)
- goto err;
-
- for (i = 0; i < len; i++) {
- rc = -ENOMEM;
- node = kzalloc(sizeof(struct cond_node), GFP_KERNEL);
- if (!node)
- goto err;
-
- rc = cond_read_node(p, node, fp);
- if (rc)
- goto err;
-
- if (i == 0)
- p->cond_list = node;
- else
- last->next = node;
- last = node;
- }
- return 0;
-err:
- cond_list_destroy(p->cond_list);
- p->cond_list = NULL;
- return rc;
-}
-
-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;
- __le32 buf[3];
- u32 len;
- int rc;
-
- len = strlen(key);
- buf[0] = cpu_to_le32(booldatum->value);
- buf[1] = cpu_to_le32(booldatum->state);
- buf[2] = cpu_to_le32(len);
- rc = put_entry(buf, sizeof(u32), 3, fp);
- if (rc)
- return rc;
- rc = put_entry(key, 1, len, fp);
- if (rc)
- return rc;
- return 0;
-}
-
-/*
- * cond_write_cond_av_list doesn't write out the av_list nodes.
- * Instead it writes out the key/value pairs from the avtab. This
- * is necessary because there is no way to uniquely identifying rules
- * in the avtab so it is not possible to associate individual rules
- * in the avtab with a conditional without saving them as part of
- * 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)
-{
- __le32 buf[1];
- struct cond_av_list *cur_list;
- u32 len;
- int rc;
-
- len = 0;
- for (cur_list = list; cur_list != NULL; cur_list = cur_list->next)
- len++;
-
- buf[0] = cpu_to_le32(len);
- rc = put_entry(buf, sizeof(u32), 1, fp);
- if (rc)
- return rc;
-
- if (len == 0)
- return 0;
-
- for (cur_list = list; cur_list != NULL; cur_list = cur_list->next) {
- rc = avtab_write_item(p, cur_list->node, fp);
- if (rc)
- return rc;
- }
-
- return 0;
-}
-
-static int cond_write_node(struct policydb *p, struct cond_node *node,
- struct policy_file *fp)
-{
- struct cond_expr *cur_expr;
- __le32 buf[2];
- int rc;
- u32 len = 0;
-
- buf[0] = cpu_to_le32(node->cur_state);
- rc = put_entry(buf, sizeof(u32), 1, fp);
- if (rc)
- return rc;
-
- for (cur_expr = node->expr; cur_expr != NULL; cur_expr = cur_expr->next)
- len++;
-
- buf[0] = cpu_to_le32(len);
- rc = put_entry(buf, sizeof(u32), 1, fp);
- if (rc)
- return rc;
-
- for (cur_expr = node->expr; cur_expr != NULL; cur_expr = cur_expr->next) {
- buf[0] = cpu_to_le32(cur_expr->expr_type);
- buf[1] = cpu_to_le32(cur_expr->bool);
- rc = put_entry(buf, sizeof(u32), 2, fp);
- if (rc)
- return rc;
- }
-
- rc = cond_write_av_list(p, node->true_list, fp);
- if (rc)
- return rc;
- rc = cond_write_av_list(p, node->false_list, fp);
- if (rc)
- return rc;
-
- return 0;
-}
-
-int cond_write_list(struct policydb *p, struct cond_node *list, void *fp)
-{
- struct cond_node *cur;
- u32 len;
- __le32 buf[1];
- int rc;
-
- len = 0;
- for (cur = list; cur != NULL; cur = cur->next)
- len++;
- buf[0] = cpu_to_le32(len);
- rc = put_entry(buf, sizeof(u32), 1, fp);
- if (rc)
- return rc;
-
- for (cur = list; cur != NULL; cur = cur->next) {
- rc = cond_write_node(p, cur, fp);
- if (rc)
- return rc;
- }
-
- return 0;
-}
-/* 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 avtab_node *node;
-
- if (!ctab || !key || !avd)
- 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)))
- avd->allowed |= node->datum.data;
- 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.data;
- if ((u16)(AVTAB_AUDITALLOW|AVTAB_ENABLED) ==
- (node->key.specified & (AVTAB_AUDITALLOW|AVTAB_ENABLED)))
- avd->auditallow |= node->datum.data;
- }
- return;
-}