#include <asm/bug.h>
#include <asm/unaligned.h>
-struct cipso_v4_domhsh_entry {
- char *domain;
- u32 valid;
- struct list_head list;
- struct rcu_head rcu;
-};
-
/* List of available DOI definitions */
-/* XXX - Updates should be minimal so having a single lock for the
- * cipso_v4_doi_list and the cipso_v4_doi_list->dom_list should be
- * okay. */
/* XXX - This currently assumes a minimal number of different DOIs in use,
* if in practice there are a lot of different DOIs this list should
* probably be turned into a hash table or something similar so we
bitmap[byte_spot] &= ~bitmask;
}
-/**
- * cipso_v4_doi_domhsh_free - Frees a domain list entry
- * @entry: the entry's RCU field
- *
- * Description:
- * This function is designed to be used as a callback to the call_rcu()
- * function so that the memory allocated to a domain list entry can be released
- * safely.
- *
- */
-static void cipso_v4_doi_domhsh_free(struct rcu_head *entry)
-{
- struct cipso_v4_domhsh_entry *ptr;
-
- ptr = container_of(entry, struct cipso_v4_domhsh_entry, rcu);
- kfree(ptr->domain);
- kfree(ptr);
-}
-
/**
* cipso_v4_cache_entry_free - Frees a cache entry
* @entry: the entry to free
struct cipso_v4_doi *iter;
list_for_each_entry_rcu(iter, &cipso_v4_doi_list, list)
- if (iter->doi == doi && iter->valid)
+ if (iter->doi == doi && atomic_read(&iter->refcount))
return iter;
return NULL;
}
}
}
- doi_def->valid = 1;
+ atomic_set(&doi_def->refcount, 1);
INIT_RCU_HEAD(&doi_def->rcu);
- INIT_LIST_HEAD(&doi_def->dom_list);
spin_lock(&cipso_v4_doi_list_lock);
if (cipso_v4_doi_search(doi_def->doi) != NULL)
return -EEXIST;
}
+/**
+ * cipso_v4_doi_free - Frees a DOI definition
+ * @entry: the entry's RCU field
+ *
+ * Description:
+ * This function frees all of the memory associated with a DOI definition.
+ *
+ */
+void cipso_v4_doi_free(struct cipso_v4_doi *doi_def)
+{
+ if (doi_def == NULL)
+ return;
+
+ switch (doi_def->type) {
+ case CIPSO_V4_MAP_STD:
+ kfree(doi_def->map.std->lvl.cipso);
+ kfree(doi_def->map.std->lvl.local);
+ kfree(doi_def->map.std->cat.cipso);
+ kfree(doi_def->map.std->cat.local);
+ break;
+ }
+ kfree(doi_def);
+}
+
+/**
+ * cipso_v4_doi_free_rcu - Frees a DOI definition via the RCU pointer
+ * @entry: the entry's RCU field
+ *
+ * Description:
+ * This function is designed to be used as a callback to the call_rcu()
+ * function so that the memory allocated to the DOI definition can be released
+ * safely.
+ *
+ */
+static void cipso_v4_doi_free_rcu(struct rcu_head *entry)
+{
+ struct cipso_v4_doi *doi_def;
+
+ doi_def = container_of(entry, struct cipso_v4_doi, rcu);
+ cipso_v4_doi_free(doi_def);
+}
+
/**
* cipso_v4_doi_remove - Remove an existing DOI from the CIPSO protocol engine
* @doi: the DOI value
* @audit_secid: the LSM secid to use in the audit message
- * @callback: the DOI cleanup/free callback
*
* Description:
- * Removes a DOI definition from the CIPSO engine, @callback is called to
- * free any memory. The NetLabel routines will be called to release their own
- * LSM domain mappings as well as our own domain list. Returns zero on
- * success and negative values on failure.
+ * Removes a DOI definition from the CIPSO engine. The NetLabel routines will
+ * be called to release their own LSM domain mappings as well as our own
+ * domain list. Returns zero on success and negative values on failure.
*
*/
-int cipso_v4_doi_remove(u32 doi,
- struct netlbl_audit *audit_info,
- void (*callback) (struct rcu_head * head))
+int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info)
{
struct cipso_v4_doi *doi_def;
- struct cipso_v4_domhsh_entry *dom_iter;
spin_lock(&cipso_v4_doi_list_lock);
doi_def = cipso_v4_doi_search(doi);
- if (doi_def != NULL) {
- doi_def->valid = 0;
- list_del_rcu(&doi_def->list);
+ if (doi_def == NULL) {
spin_unlock(&cipso_v4_doi_list_lock);
- rcu_read_lock();
- list_for_each_entry_rcu(dom_iter, &doi_def->dom_list, list)
- if (dom_iter->valid)
- netlbl_cfg_map_del(dom_iter->domain,
- audit_info);
- rcu_read_unlock();
- cipso_v4_cache_invalidate();
- call_rcu(&doi_def->rcu, callback);
- return 0;
+ return -ENOENT;
+ }
+ if (!atomic_dec_and_test(&doi_def->refcount)) {
+ spin_unlock(&cipso_v4_doi_list_lock);
+ return -EBUSY;
}
+ list_del_rcu(&doi_def->list);
spin_unlock(&cipso_v4_doi_list_lock);
- return -ENOENT;
+ cipso_v4_cache_invalidate();
+ call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu);
+
+ return 0;
}
/**
- * cipso_v4_doi_getdef - Returns a pointer to a valid DOI definition
+ * cipso_v4_doi_getdef - Returns a reference to a valid DOI definition
* @doi: the DOI value
*
* Description:
* Searches for a valid DOI definition and if one is found it is returned to
* the caller. Otherwise NULL is returned. The caller must ensure that
- * rcu_read_lock() is held while accessing the returned definition.
+ * rcu_read_lock() is held while accessing the returned definition and the DOI
+ * definition reference count is decremented when the caller is done.
*
*/
struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi)
{
- return cipso_v4_doi_search(doi);
+ struct cipso_v4_doi *doi_def;
+
+ rcu_read_lock();
+ doi_def = cipso_v4_doi_search(doi);
+ if (doi_def == NULL)
+ goto doi_getdef_return;
+ if (!atomic_inc_not_zero(&doi_def->refcount))
+ doi_def = NULL;
+
+doi_getdef_return:
+ rcu_read_unlock();
+ return doi_def;
+}
+
+/**
+ * cipso_v4_doi_putdef - Releases a reference for the given DOI definition
+ * @doi_def: the DOI definition
+ *
+ * Description:
+ * Releases a DOI definition reference obtained from cipso_v4_doi_getdef().
+ *
+ */
+void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def)
+{
+ if (doi_def == NULL)
+ return;
+
+ if (!atomic_dec_and_test(&doi_def->refcount))
+ return;
+ spin_lock(&cipso_v4_doi_list_lock);
+ list_del_rcu(&doi_def->list);
+ spin_unlock(&cipso_v4_doi_list_lock);
+
+ cipso_v4_cache_invalidate();
+ call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu);
}
/**
rcu_read_lock();
list_for_each_entry_rcu(iter_doi, &cipso_v4_doi_list, list)
- if (iter_doi->valid) {
+ if (atomic_read(&iter_doi->refcount) > 0) {
if (doi_cnt++ < *skip_cnt)
continue;
ret_val = callback(iter_doi, cb_arg);
return ret_val;
}
-/**
- * cipso_v4_doi_domhsh_add - Adds a domain entry to a DOI definition
- * @doi_def: the DOI definition
- * @domain: the domain to add
- *
- * Description:
- * Adds the @domain to the DOI specified by @doi_def, this function
- * should only be called by external functions (i.e. NetLabel). This function
- * does allocate memory. Returns zero on success, negative values on failure.
- *
- */
-int cipso_v4_doi_domhsh_add(struct cipso_v4_doi *doi_def, const char *domain)
-{
- struct cipso_v4_domhsh_entry *iter;
- struct cipso_v4_domhsh_entry *new_dom;
-
- new_dom = kzalloc(sizeof(*new_dom), GFP_KERNEL);
- if (new_dom == NULL)
- return -ENOMEM;
- if (domain) {
- new_dom->domain = kstrdup(domain, GFP_KERNEL);
- if (new_dom->domain == NULL) {
- kfree(new_dom);
- return -ENOMEM;
- }
- }
- new_dom->valid = 1;
- INIT_RCU_HEAD(&new_dom->rcu);
-
- spin_lock(&cipso_v4_doi_list_lock);
- list_for_each_entry(iter, &doi_def->dom_list, list)
- if (iter->valid &&
- ((domain != NULL && iter->domain != NULL &&
- strcmp(iter->domain, domain) == 0) ||
- (domain == NULL && iter->domain == NULL))) {
- spin_unlock(&cipso_v4_doi_list_lock);
- kfree(new_dom->domain);
- kfree(new_dom);
- return -EEXIST;
- }
- list_add_tail_rcu(&new_dom->list, &doi_def->dom_list);
- spin_unlock(&cipso_v4_doi_list_lock);
-
- return 0;
-}
-
-/**
- * cipso_v4_doi_domhsh_remove - Removes a domain entry from a DOI definition
- * @doi_def: the DOI definition
- * @domain: the domain to remove
- *
- * Description:
- * Removes the @domain from the DOI specified by @doi_def, this function
- * should only be called by external functions (i.e. NetLabel). Returns zero
- * on success and negative values on error.
- *
- */
-int cipso_v4_doi_domhsh_remove(struct cipso_v4_doi *doi_def,
- const char *domain)
-{
- struct cipso_v4_domhsh_entry *iter;
-
- spin_lock(&cipso_v4_doi_list_lock);
- list_for_each_entry(iter, &doi_def->dom_list, list)
- if (iter->valid &&
- ((domain != NULL && iter->domain != NULL &&
- strcmp(iter->domain, domain) == 0) ||
- (domain == NULL && iter->domain == NULL))) {
- iter->valid = 0;
- list_del_rcu(&iter->list);
- spin_unlock(&cipso_v4_doi_list_lock);
- call_rcu(&iter->rcu, cipso_v4_doi_domhsh_free);
- return 0;
- }
- spin_unlock(&cipso_v4_doi_list_lock);
-
- return -ENOENT;
-}
-
/*
* Label Mapping Functions
*/
projects / ~andy / linux / blobdiff