diff options
-rw-r--r-- | security/smack/smack.h | 13 | ||||
-rw-r--r-- | security/smack/smack_access.c | 29 | ||||
-rw-r--r-- | security/smack/smack_lsm.c | 42 | ||||
-rw-r--r-- | security/smack/smackfs.c | 180 |
4 files changed, 150 insertions, 114 deletions
diff --git a/security/smack/smack.h b/security/smack/smack.h index 339614c76e6..076b8e8a51a 100644 --- a/security/smack/smack.h +++ b/security/smack/smack.h @@ -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? */ diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c index 6a0377f3862..b3b59b1e93d 100644 --- a/security/smack/smack_access.c +++ b/security/smack/smack_access.c @@ -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; } /* diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index a113a779f00..19de5e23768 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -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); } /** diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c index ab167037b2d..80f4b4a4572 100644 --- a/security/smack/smackfs.c +++ b/security/smack/smackfs.c @@ -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, |