diff options
Diffstat (limited to 'security/smack/smack_access.c')
| -rw-r--r-- | security/smack/smack_access.c | 77 |
1 files changed, 66 insertions, 11 deletions
diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c index 6a0377f3862..c062e9467b6 100644 --- a/security/smack/smack_access.c +++ b/security/smack/smack_access.c @@ -84,6 +84,8 @@ int log_policy = SMACK_AUDIT_DENIED; * * Do the object check first because that is more * likely to differ. + * + * Allowing write access implies allowing locking. */ int smk_access_entry(char *subject_label, char *object_label, struct list_head *rule_list) @@ -99,6 +101,11 @@ int smk_access_entry(char *subject_label, char *object_label, } } + /* + * MAY_WRITE implies MAY_LOCK. + */ + if ((may & MAY_WRITE) == MAY_WRITE) + may |= MAY_LOCK; return may; } @@ -185,20 +192,21 @@ out_audit: } /** - * smk_curacc - determine if current has a specific access to an object + * smk_tskacc - determine if a task has a specific access to an object + * @tsp: a pointer to the subject task * @obj_label: a pointer to the object's Smack label * @mode: the access requested, in "MAY" format * @a : common audit data * - * This function checks the current subject label/object label pair + * This function checks the subject task's label/object label pair * in the access rule list and returns 0 if the access is permitted, - * non zero otherwise. It allows that current may have the capability + * non zero otherwise. It allows that the task may have the capability * to override the rules. */ -int smk_curacc(char *obj_label, u32 mode, struct smk_audit_info *a) +int smk_tskacc(struct task_smack *subject, char *obj_label, + u32 mode, struct smk_audit_info *a) { - struct task_smack *tsp = current_security(); - struct smack_known *skp = smk_of_task(tsp); + struct smack_known *skp = smk_of_task(subject); int may; int rc; @@ -212,7 +220,7 @@ int smk_curacc(char *obj_label, u32 mode, struct smk_audit_info *a) * it can further restrict access. */ may = smk_access_entry(skp->smk_known, obj_label, - &tsp->smk_rules); + &subject->smk_rules); if (may < 0) goto out_audit; if ((mode & may) == mode) @@ -234,6 +242,24 @@ out_audit: return rc; } +/** + * smk_curacc - determine if current has a specific access to an object + * @obj_label: a pointer to the object's Smack label + * @mode: the access requested, in "MAY" format + * @a : common audit data + * + * This function checks the current subject label/object label pair + * in the access rule list and returns 0 if the access is permitted, + * non zero otherwise. It allows that current may have the capability + * to override the rules. + */ +int smk_curacc(char *obj_label, u32 mode, struct smk_audit_info *a) +{ + struct task_smack *tsp = current_security(); + + return smk_tskacc(tsp, obj_label, mode, a); +} + #ifdef CONFIG_AUDIT /** * smack_str_from_perm : helper to transalate an int to a @@ -245,6 +271,7 @@ out_audit: static inline void smack_str_from_perm(char *string, int access) { int i = 0; + if (access & MAY_READ) string[i++] = 'r'; if (access & MAY_WRITE) @@ -255,6 +282,8 @@ static inline void smack_str_from_perm(char *string, int access) string[i++] = 'a'; if (access & MAY_TRANSMUTE) string[i++] = 't'; + if (access & MAY_LOCK) + string[i++] = 'l'; string[i] = '\0'; } /** @@ -275,7 +304,10 @@ static void smack_log_callback(struct audit_buffer *ab, void *a) audit_log_untrustedstring(ab, sad->subject); audit_log_format(ab, " object="); audit_log_untrustedstring(ab, sad->object); - audit_log_format(ab, " requested=%s", sad->request); + if (sad->request[0] == '\0') + audit_log_format(ab, " labels_differ"); + else + audit_log_format(ab, " requested=%s", sad->request); } /** @@ -325,6 +357,25 @@ void smack_log(char *subject_label, char *object_label, int request, DEFINE_MUTEX(smack_known_lock); +struct hlist_head smack_known_hash[SMACK_HASH_SLOTS]; + +/** + * smk_insert_entry - insert a smack label into a hash map, + * + * this function must be called under smack_known_lock + */ +void smk_insert_entry(struct smack_known *skp) +{ + unsigned int hash; + struct hlist_head *head; + + hash = full_name_hash(skp->smk_known, strlen(skp->smk_known)); + head = &smack_known_hash[hash & (SMACK_HASH_SLOTS - 1)]; + + hlist_add_head_rcu(&skp->smk_hashed, head); + list_add_rcu(&skp->list, &smack_known_list); +} + /** * smk_find_entry - find a label on the list, return the list entry * @string: a text string that might be a Smack label @@ -334,12 +385,16 @@ DEFINE_MUTEX(smack_known_lock); */ struct smack_known *smk_find_entry(const char *string) { + unsigned int hash; + struct hlist_head *head; struct smack_known *skp; - list_for_each_entry_rcu(skp, &smack_known_list, list) { + hash = full_name_hash(string, strlen(string)); + head = &smack_known_hash[hash & (SMACK_HASH_SLOTS - 1)]; + + hlist_for_each_entry_rcu(skp, head, smk_hashed) if (strcmp(skp->smk_known, string) == 0) return skp; - } return NULL; } @@ -475,7 +530,7 @@ struct smack_known *smk_import_entry(const char *string, int len) * Make sure that the entry is actually * filled before putting it on the list. */ - list_add_rcu(&skp->list, &smack_known_list); + smk_insert_entry(skp); goto unlockout; } /* |