Merge branch 'smack-for-3.12' of git://git.gitorious.org/smack-next/kernel into ra...
authorJames Morris <james.l.morris@oracle.com>
Thu, 22 Aug 2013 16:50:12 +0000 (02:50 +1000)
committerJames Morris <james.l.morris@oracle.com>
Thu, 22 Aug 2013 16:50:12 +0000 (02:50 +1000)
security/smack/smack.h
security/smack/smack_access.c
security/smack/smack_lsm.c
security/smack/smackfs.c

index 339614c..076b8e8 100644 (file)
@@ -53,6 +53,7 @@
  */
 struct smack_known {
        struct list_head                list;
+       struct hlist_node               smk_hashed;
        char                            *smk_known;
        u32                             smk_secid;
        struct netlbl_lsm_secattr       smk_netlabel;   /* on wire labels */
@@ -167,9 +168,13 @@ struct smk_port_label {
 #define SMACK_CIPSO_DOI_INVALID                -1      /* Not a DOI */
 #define SMACK_CIPSO_DIRECT_DEFAULT     250     /* Arbitrary */
 #define SMACK_CIPSO_MAPPED_DEFAULT     251     /* Also arbitrary */
-#define SMACK_CIPSO_MAXCATVAL          63      /* Bigger gets harder */
 #define SMACK_CIPSO_MAXLEVEL            255     /* CIPSO 2.2 standard */
-#define SMACK_CIPSO_MAXCATNUM           239     /* CIPSO 2.2 standard */
+/*
+ * CIPSO 2.2 standard is 239, but Smack wants to use the
+ * categories in a structured way that limits the value to
+ * the bits in 23 bytes, hence the unusual number.
+ */
+#define SMACK_CIPSO_MAXCATNUM           184     /* 23 * 8 */
 
 /*
  * Flag for transmute access
@@ -222,6 +227,7 @@ char *smk_parse_smack(const char *string, int len);
 int smk_netlbl_mls(int, char *, struct netlbl_lsm_secattr *, int);
 char *smk_import(const char *, int);
 struct smack_known *smk_import_entry(const char *, int);
+void smk_insert_entry(struct smack_known *skp);
 struct smack_known *smk_find_entry(const char *);
 u32 smack_to_secid(const char *);
 
@@ -247,6 +253,9 @@ extern struct list_head smk_netlbladdr_list;
 
 extern struct security_operations smack_ops;
 
+#define SMACK_HASH_SLOTS 16
+extern struct hlist_head smack_known_hash[SMACK_HASH_SLOTS];
+
 /*
  * Is the directory transmuting?
  */
index 6a0377f..b3b59b1 100644 (file)
@@ -325,6 +325,25 @@ 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 +353,16 @@ 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 +498,7 @@ 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;
        }
        /*
index a113a77..19de5e2 100644 (file)
@@ -3063,6 +3063,8 @@ static struct smack_known *smack_from_secattr(struct netlbl_lsm_secattr *sap,
 {
        struct smack_known *skp;
        int found = 0;
+       int acat;
+       int kcat;
 
        if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) {
                /*
@@ -3079,12 +3081,28 @@ static struct smack_known *smack_from_secattr(struct netlbl_lsm_secattr *sap,
                list_for_each_entry(skp, &smack_known_list, list) {
                        if (sap->attr.mls.lvl != skp->smk_netlabel.attr.mls.lvl)
                                continue;
-                       if (memcmp(sap->attr.mls.cat,
-                               skp->smk_netlabel.attr.mls.cat,
-                               SMK_CIPSOLEN) != 0)
-                               continue;
-                       found = 1;
-                       break;
+                       /*
+                        * Compare the catsets. Use the netlbl APIs.
+                        */
+                       if ((sap->flags & NETLBL_SECATTR_MLS_CAT) == 0) {
+                               if ((skp->smk_netlabel.flags &
+                                    NETLBL_SECATTR_MLS_CAT) == 0)
+                                       found = 1;
+                               break;
+                       }
+                       for (acat = -1, kcat = -1; acat == kcat; ) {
+                               acat = netlbl_secattr_catmap_walk(
+                                       sap->attr.mls.cat, acat + 1);
+                               kcat = netlbl_secattr_catmap_walk(
+                                       skp->smk_netlabel.attr.mls.cat,
+                                       kcat + 1);
+                               if (acat < 0 || kcat < 0)
+                                       break;
+                       }
+                       if (acat == kcat) {
+                               found = 1;
+                               break;
+                       }
                }
                rcu_read_unlock();
 
@@ -3876,12 +3894,12 @@ static __init void init_smack_known_list(void)
        /*
         * Create the known labels list
         */
-       list_add(&smack_known_huh.list, &smack_known_list);
-       list_add(&smack_known_hat.list, &smack_known_list);
-       list_add(&smack_known_star.list, &smack_known_list);
-       list_add(&smack_known_floor.list, &smack_known_list);
-       list_add(&smack_known_invalid.list, &smack_known_list);
-       list_add(&smack_known_web.list, &smack_known_list);
+       smk_insert_entry(&smack_known_huh);
+       smk_insert_entry(&smack_known_hat);
+       smk_insert_entry(&smack_known_star);
+       smk_insert_entry(&smack_known_floor);
+       smk_insert_entry(&smack_known_invalid);
+       smk_insert_entry(&smack_known_web);
 }
 
 /**
index ab16703..80f4b4a 100644 (file)
@@ -368,56 +368,43 @@ static int smk_parse_rule(const char *data, struct smack_parsed_rule *rule,
  * @data: string to be parsed, null terminated
  * @rule: Will be filled with Smack parsed rule
  * @import: if non-zero, import labels
- * @change: if non-zero, data is from /smack/change-rule
+ * @tokens: numer of substrings expected in data
  *
- * Returns 0 on success, -1 on failure
+ * Returns number of processed bytes on success, -1 on failure.
  */
-static int smk_parse_long_rule(const char *data, struct smack_parsed_rule *rule,
-                               int import, int change)
+static ssize_t smk_parse_long_rule(char *data, struct smack_parsed_rule *rule,
+                               int import, int tokens)
 {
-       char *subject;
-       char *object;
-       char *access1;
-       char *access2;
-       int datalen;
-       int rc = -1;
+       ssize_t cnt = 0;
+       char *tok[4];
+       int i;
 
-       /* This is inefficient */
-       datalen = strlen(data);
+       /*
+        * Parsing the rule in-place, filling all white-spaces with '\0'
+        */
+       for (i = 0; i < tokens; ++i) {
+               while (isspace(data[cnt]))
+                       data[cnt++] = '\0';
 
-       /* Our first element can be 64 + \0 with no spaces */
-       subject = kzalloc(datalen + 1, GFP_KERNEL);
-       if (subject == NULL)
-               return -1;
-       object = kzalloc(datalen, GFP_KERNEL);
-       if (object == NULL)
-               goto free_out_s;
-       access1 = kzalloc(datalen, GFP_KERNEL);
-       if (access1 == NULL)
-               goto free_out_o;
-       access2 = kzalloc(datalen, GFP_KERNEL);
-       if (access2 == NULL)
-               goto free_out_a;
-
-       if (change) {
-               if (sscanf(data, "%s %s %s %s",
-                       subject, object, access1, access2) == 4)
-                       rc = smk_fill_rule(subject, object, access1, access2,
-                               rule, import, 0);
-       } else {
-               if (sscanf(data, "%s %s %s", subject, object, access1) == 3)
-                       rc = smk_fill_rule(subject, object, access1, NULL,
-                               rule, import, 0);
+               if (data[cnt] == '\0')
+                       /* Unexpected end of data */
+                       return -1;
+
+               tok[i] = data + cnt;
+
+               while (data[cnt] && !isspace(data[cnt]))
+                       ++cnt;
        }
+       while (isspace(data[cnt]))
+               data[cnt++] = '\0';
 
-       kfree(access2);
-free_out_a:
-       kfree(access1);
-free_out_o:
-       kfree(object);
-free_out_s:
-       kfree(subject);
-       return rc;
+       while (i < 4)
+               tok[i++] = NULL;
+
+       if (smk_fill_rule(tok[0], tok[1], tok[2], tok[3], rule, import, 0))
+               return -1;
+
+       return cnt;
 }
 
 #define SMK_FIXED24_FMT        0       /* Fixed 24byte label format */
@@ -447,11 +434,12 @@ static ssize_t smk_write_rules_list(struct file *file, const char __user *buf,
                                        struct list_head *rule_list,
                                        struct mutex *rule_lock, int format)
 {
-       struct smack_parsed_rule *rule;
+       struct smack_parsed_rule rule;
        char *data;
-       int datalen;
-       int rc = -EINVAL;
-       int load = 0;
+       int rc;
+       int trunc = 0;
+       int tokens;
+       ssize_t cnt = 0;
 
        /*
         * No partial writes.
@@ -466,11 +454,14 @@ static ssize_t smk_write_rules_list(struct file *file, const char __user *buf,
                 */
                if (count != SMK_OLOADLEN && count != SMK_LOADLEN)
                        return -EINVAL;
-               datalen = SMK_LOADLEN;
-       } else
-               datalen = count + 1;
+       } else {
+               if (count >= PAGE_SIZE) {
+                       count = PAGE_SIZE - 1;
+                       trunc = 1;
+               }
+       }
 
-       data = kzalloc(datalen, GFP_KERNEL);
+       data = kmalloc(count + 1, GFP_KERNEL);
        if (data == NULL)
                return -ENOMEM;
 
@@ -479,47 +470,49 @@ static ssize_t smk_write_rules_list(struct file *file, const char __user *buf,
                goto out;
        }
 
-       rule = kzalloc(sizeof(*rule), GFP_KERNEL);
-       if (rule == NULL) {
-               rc = -ENOMEM;
-               goto out;
+       /*
+        * In case of parsing only part of user buf,
+        * avoid having partial rule at the data buffer
+        */
+       if (trunc) {
+               while (count > 0 && (data[count - 1] != '\n'))
+                       --count;
+               if (count == 0) {
+                       rc = -EINVAL;
+                       goto out;
+               }
        }
 
-       if (format == SMK_LONG_FMT) {
-               /*
-                * Be sure the data string is terminated.
-                */
-               data[count] = '\0';
-               if (smk_parse_long_rule(data, rule, 1, 0))
-                       goto out_free_rule;
-       } else if (format == SMK_CHANGE_FMT) {
-               data[count] = '\0';
-               if (smk_parse_long_rule(data, rule, 1, 1))
-                       goto out_free_rule;
-       } else {
-               /*
-                * More on the minor hack for backward compatibility
-                */
-               if (count == (SMK_OLOADLEN))
-                       data[SMK_OLOADLEN] = '-';
-               if (smk_parse_rule(data, rule, 1))
-                       goto out_free_rule;
-       }
+       data[count] = '\0';
+       tokens = (format == SMK_CHANGE_FMT ? 4 : 3);
+       while (cnt < count) {
+               if (format == SMK_FIXED24_FMT) {
+                       rc = smk_parse_rule(data, &rule, 1);
+                       if (rc != 0) {
+                               rc = -EINVAL;
+                               goto out;
+                       }
+                       cnt = count;
+               } else {
+                       rc = smk_parse_long_rule(data + cnt, &rule, 1, tokens);
+                       if (rc <= 0) {
+                               rc = -EINVAL;
+                               goto out;
+                       }
+                       cnt += rc;
+               }
 
-       if (rule_list == NULL) {
-               load = 1;
-               rule_list = &rule->smk_subject->smk_rules;
-               rule_lock = &rule->smk_subject->smk_rules_lock;
-       }
+               if (rule_list == NULL)
+                       rc = smk_set_access(&rule, &rule.smk_subject->smk_rules,
+                               &rule.smk_subject->smk_rules_lock, 1);
+               else
+                       rc = smk_set_access(&rule, rule_list, rule_lock, 0);
 
-       rc = smk_set_access(rule, rule_list, rule_lock, load);
-       if (rc == 0) {
-               rc = count;
-               goto out;
+               if (rc)
+                       goto out;
        }
 
-out_free_rule:
-       kfree(rule);
+       rc = cnt;
 out:
        kfree(data);
        return rc;
@@ -901,7 +894,7 @@ static ssize_t smk_set_cipso(struct file *file, const char __user *buf,
        for (i = 0; i < catlen; i++) {
                rule += SMK_DIGITLEN;
                ret = sscanf(rule, "%u", &cat);
-               if (ret != 1 || cat > SMACK_CIPSO_MAXCATVAL)
+               if (ret != 1 || cat > SMACK_CIPSO_MAXCATNUM)
                        goto out;
 
                smack_catset_bit(cat, mapcatset);
@@ -1840,7 +1833,6 @@ static ssize_t smk_user_access(struct file *file, const char __user *buf,
 {
        struct smack_parsed_rule rule;
        char *data;
-       char *cod;
        int res;
 
        data = simple_transaction_get(file, buf, count);
@@ -1853,18 +1845,12 @@ static ssize_t smk_user_access(struct file *file, const char __user *buf,
                res = smk_parse_rule(data, &rule, 0);
        } else {
                /*
-                * Copy the data to make sure the string is terminated.
+                * simple_transaction_get() returns null-terminated data
                 */
-               cod = kzalloc(count + 1, GFP_KERNEL);
-               if (cod == NULL)
-                       return -ENOMEM;
-               memcpy(cod, data, count);
-               cod[count] = '\0';
-               res = smk_parse_long_rule(cod, &rule, 0, 0);
-               kfree(cod);
+               res = smk_parse_long_rule(data, &rule, 0, 3);
        }
 
-       if (res)
+       if (res < 0)
                return -EINVAL;
 
        res = smk_access(rule.smk_subject, rule.smk_object,