struct smack_known smack_known_huh = {
.smk_known = "?",
.smk_secid = 2,
- .smk_cipso = NULL,
};
struct smack_known smack_known_hat = {
.smk_known = "^",
.smk_secid = 3,
- .smk_cipso = NULL,
};
struct smack_known smack_known_star = {
.smk_known = "*",
.smk_secid = 4,
- .smk_cipso = NULL,
};
struct smack_known smack_known_floor = {
.smk_known = "_",
.smk_secid = 5,
- .smk_cipso = NULL,
};
struct smack_known smack_known_invalid = {
.smk_known = "",
.smk_secid = 6,
- .smk_cipso = NULL,
};
struct smack_known smack_known_web = {
.smk_known = "@",
.smk_secid = 7,
- .smk_cipso = NULL,
};
LIST_HEAD(smack_known_list);
* entry is found returns -ENOENT.
*
* NOTE:
- * Even though Smack labels are usually shared on smack_list
- * labels that come in off the network can't be imported
- * and added to the list for locking reasons.
*
- * Therefore, it is necessary to check the contents of the labels,
- * not just the pointer values. Of course, in most cases the labels
- * will be on the list, so checking the pointers may be a worthwhile
- * optimization.
+ * Earlier versions of this function allowed for labels that
+ * were not on the label list. This was done to allow for
+ * labels to come over the network that had never been seen
+ * before on this host. Unless the receiving socket has the
+ * star label this will always result in a failure check. The
+ * star labeled socket case is now handled in the networking
+ * hooks so there is no case where the label is not on the
+ * label list. Checking to see if the address of two labels
+ * is the same is now a reliable test.
+ *
+ * Do the object check first because that is more
+ * likely to differ.
*/
int smk_access_entry(char *subject_label, char *object_label,
struct list_head *rule_list)
struct smack_rule *srp;
list_for_each_entry_rcu(srp, rule_list, list) {
- if (srp->smk_subject == subject_label ||
- strcmp(srp->smk_subject, subject_label) == 0) {
- if (srp->smk_object == object_label ||
- strcmp(srp->smk_object, object_label) == 0) {
- may = srp->smk_access;
- break;
- }
+ if (srp->smk_object == object_label &&
+ srp->smk_subject == subject_label) {
+ may = srp->smk_access;
+ break;
}
}
* access rule list and returns 0 if the access is permitted,
* non zero otherwise.
*
- * Even though Smack labels are usually shared on smack_list
- * labels that come in off the network can't be imported
- * and added to the list for locking reasons.
- *
- * Therefore, it is necessary to check the contents of the labels,
- * not just the pointer values. Of course, in most cases the labels
- * will be on the list, so checking the pointers may be a worthwhile
- * optimization.
+ * Smack labels are shared on smack_list
*/
int smk_access(char *subject_label, char *object_label, int request,
struct smk_audit_info *a)
{
+ struct smack_known *skp;
int may = MAY_NOT;
int rc = 0;
*
* A star subject can't access any object.
*/
- if (subject_label == smack_known_star.smk_known ||
- strcmp(subject_label, smack_known_star.smk_known) == 0) {
+ if (subject_label == smack_known_star.smk_known) {
rc = -EACCES;
goto out_audit;
}
* An internet subject can access any object.
*/
if (object_label == smack_known_web.smk_known ||
- subject_label == smack_known_web.smk_known ||
- strcmp(object_label, smack_known_web.smk_known) == 0 ||
- strcmp(subject_label, smack_known_web.smk_known) == 0)
+ subject_label == smack_known_web.smk_known)
goto out_audit;
/*
* A star object can be accessed by any subject.
*/
- if (object_label == smack_known_star.smk_known ||
- strcmp(object_label, smack_known_star.smk_known) == 0)
+ if (object_label == smack_known_star.smk_known)
goto out_audit;
/*
* An object can be accessed in any way by a subject
* with the same label.
*/
- if (subject_label == object_label ||
- strcmp(subject_label, object_label) == 0)
+ if (subject_label == object_label)
goto out_audit;
/*
* A hat subject can read any object.
* A floor object can be read by any subject.
*/
if ((request & MAY_ANYREAD) == request) {
- if (object_label == smack_known_floor.smk_known ||
- strcmp(object_label, smack_known_floor.smk_known) == 0)
+ if (object_label == smack_known_floor.smk_known)
goto out_audit;
- if (subject_label == smack_known_hat.smk_known ||
- strcmp(subject_label, smack_known_hat.smk_known) == 0)
+ if (subject_label == smack_known_hat.smk_known)
goto out_audit;
}
/*
* good. A negative response from smk_access_entry()
* indicates there is no entry for this pair.
*/
+ skp = smk_find_entry(subject_label);
rcu_read_lock();
- may = smk_access_entry(subject_label, object_label, &smack_rule_list);
+ may = smk_access_entry(subject_label, object_label, &skp->smk_rules);
rcu_read_unlock();
if (may > 0 && (request & may) == request)
}
/*
- * Return if a specific label has been designated as the
- * only one that gets privilege and current does not
- * have that label.
+ * Allow for priviliged to override policy.
*/
- if (smack_onlycap != NULL && smack_onlycap != sp)
- goto out_audit;
-
- if (capable(CAP_MAC_OVERRIDE))
+ if (rc != 0 && smack_privileged(CAP_MAC_OVERRIDE))
rc = 0;
out_audit:
string[i++] = 'x';
if (access & MAY_APPEND)
string[i++] = 'a';
+ if (access & MAY_TRANSMUTE)
+ string[i++] = 't';
string[i] = '\0';
}
/**
}
#endif
-static DEFINE_MUTEX(smack_known_lock);
+DEFINE_MUTEX(smack_known_lock);
+
+/**
+ * smk_find_entry - find a label on the list, return the list entry
+ * @string: a text string that might be a Smack label
+ *
+ * Returns a pointer to the entry in the label list that
+ * matches the passed string.
+ */
+struct smack_known *smk_find_entry(const char *string)
+{
+ struct smack_known *skp;
+
+ list_for_each_entry_rcu(skp, &smack_known_list, list) {
+ if (strcmp(skp->smk_known, string) == 0)
+ return skp;
+ }
+
+ return NULL;
+}
+
+/**
+ * smk_parse_smack - parse smack label from a text string
+ * @string: a text string that might contain a Smack label
+ * @len: the maximum size, or zero if it is NULL terminated.
+ *
+ * Returns a pointer to the clean label, or NULL
+ */
+char *smk_parse_smack(const char *string, int len)
+{
+ char *smack;
+ int i;
+
+ if (len <= 0)
+ len = strlen(string) + 1;
+
+ /*
+ * Reserve a leading '-' as an indicator that
+ * this isn't a label, but an option to interfaces
+ * including /smack/cipso and /smack/cipso2
+ */
+ if (string[0] == '-')
+ return NULL;
+
+ for (i = 0; i < len; i++)
+ if (string[i] > '~' || string[i] <= ' ' || string[i] == '/' ||
+ string[i] == '"' || string[i] == '\\' || string[i] == '\'')
+ break;
+
+ if (i == 0 || i >= SMK_LONGLABEL)
+ return NULL;
+
+ smack = kzalloc(i + 1, GFP_KERNEL);
+ if (smack != NULL) {
+ strncpy(smack, string, i + 1);
+ smack[i] = '\0';
+ }
+ return smack;
+}
+
+/**
+ * smk_netlbl_mls - convert a catset to netlabel mls categories
+ * @catset: the Smack categories
+ * @sap: where to put the netlabel categories
+ *
+ * Allocates and fills attr.mls
+ * Returns 0 on success, error code on failure.
+ */
+int smk_netlbl_mls(int level, char *catset, struct netlbl_lsm_secattr *sap,
+ int len)
+{
+ unsigned char *cp;
+ unsigned char m;
+ int cat;
+ int rc;
+ int byte;
+
+ sap->flags |= NETLBL_SECATTR_MLS_CAT;
+ sap->attr.mls.lvl = level;
+ sap->attr.mls.cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC);
+ if (!sap->attr.mls.cat)
+ return -ENOMEM;
+ sap->attr.mls.cat->startbit = 0;
+
+ for (cat = 1, cp = catset, byte = 0; byte < len; cp++, byte++)
+ for (m = 0x80; m != 0; m >>= 1, cat++) {
+ if ((m & *cp) == 0)
+ continue;
+ rc = netlbl_secattr_catmap_setbit(sap->attr.mls.cat,
+ cat, GFP_ATOMIC);
+ if (rc < 0) {
+ netlbl_secattr_catmap_free(sap->attr.mls.cat);
+ return rc;
+ }
+ }
+
+ return 0;
+}
/**
* smk_import_entry - import a label, return the list entry
struct smack_known *smk_import_entry(const char *string, int len)
{
struct smack_known *skp;
- char smack[SMK_LABELLEN];
- int found;
- int i;
-
- if (len <= 0 || len > SMK_MAXLEN)
- len = SMK_MAXLEN;
-
- for (i = 0, found = 0; i < SMK_LABELLEN; i++) {
- if (found)
- smack[i] = '\0';
- else if (i >= len || string[i] > '~' || string[i] <= ' ' ||
- string[i] == '/' || string[i] == '"' ||
- string[i] == '\\' || string[i] == '\'') {
- smack[i] = '\0';
- found = 1;
- } else
- smack[i] = string[i];
- }
+ char *smack;
+ int slen;
+ int rc;
- if (smack[0] == '\0')
+ smack = smk_parse_smack(string, len);
+ if (smack == NULL)
return NULL;
mutex_lock(&smack_known_lock);
- found = 0;
- list_for_each_entry_rcu(skp, &smack_known_list, list) {
- if (strncmp(skp->smk_known, smack, SMK_MAXLEN) == 0) {
- found = 1;
- break;
- }
- }
+ skp = smk_find_entry(smack);
+ if (skp != NULL)
+ goto freeout;
- if (found == 0) {
- skp = kzalloc(sizeof(struct smack_known), GFP_KERNEL);
- if (skp != NULL) {
- strncpy(skp->smk_known, smack, SMK_MAXLEN);
- skp->smk_secid = smack_next_secid++;
- skp->smk_cipso = NULL;
- spin_lock_init(&skp->smk_cipsolock);
- /*
- * Make sure that the entry is actually
- * filled before putting it on the list.
- */
- list_add_rcu(&skp->list, &smack_known_list);
- }
- }
+ skp = kzalloc(sizeof(*skp), GFP_KERNEL);
+ if (skp == NULL)
+ goto freeout;
+ skp->smk_known = smack;
+ skp->smk_secid = smack_next_secid++;
+ skp->smk_netlabel.domain = skp->smk_known;
+ skp->smk_netlabel.flags =
+ NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL;
+ /*
+ * If direct labeling works use it.
+ * Otherwise use mapped labeling.
+ */
+ slen = strlen(smack);
+ if (slen < SMK_CIPSOLEN)
+ rc = smk_netlbl_mls(smack_cipso_direct, skp->smk_known,
+ &skp->smk_netlabel, slen);
+ else
+ rc = smk_netlbl_mls(smack_cipso_mapped, (char *)&skp->smk_secid,
+ &skp->smk_netlabel, sizeof(skp->smk_secid));
+
+ if (rc >= 0) {
+ INIT_LIST_HEAD(&skp->smk_rules);
+ mutex_init(&skp->smk_rules_lock);
+ /*
+ * Make sure that the entry is actually
+ * filled before putting it on the list.
+ */
+ list_add_rcu(&skp->list, &smack_known_list);
+ goto unlockout;
+ }
+ /*
+ * smk_netlbl_mls failed.
+ */
+ kfree(skp);
+ skp = NULL;
+freeout:
+ kfree(smack);
+unlockout:
mutex_unlock(&smack_known_lock);
return skp;
*/
u32 smack_to_secid(const char *smack)
{
- struct smack_known *skp;
+ struct smack_known *skp = smk_find_entry(smack);
- rcu_read_lock();
- list_for_each_entry_rcu(skp, &smack_known_list, list) {
- if (strncmp(skp->smk_known, smack, SMK_MAXLEN) == 0) {
- rcu_read_unlock();
- return skp->smk_secid;
- }
- }
- rcu_read_unlock();
- return 0;
-}
-
-/**
- * smack_from_cipso - find the Smack label associated with a CIPSO option
- * @level: Bell & LaPadula level from the network
- * @cp: Bell & LaPadula categories from the network
- * @result: where to put the Smack value
- *
- * This is a simple lookup in the label table.
- *
- * This is an odd duck as far as smack handling goes in that
- * it sends back a copy of the smack label rather than a pointer
- * to the master list. This is done because it is possible for
- * a foreign host to send a smack label that is new to this
- * machine and hence not on the list. That would not be an
- * issue except that adding an entry to the master list can't
- * be done at that point.
- */
-void smack_from_cipso(u32 level, char *cp, char *result)
-{
- struct smack_known *kp;
- char *final = NULL;
-
- rcu_read_lock();
- list_for_each_entry(kp, &smack_known_list, list) {
- if (kp->smk_cipso == NULL)
- continue;
-
- spin_lock_bh(&kp->smk_cipsolock);
-
- if (kp->smk_cipso->smk_level == level &&
- memcmp(kp->smk_cipso->smk_catset, cp, SMK_LABELLEN) == 0)
- final = kp->smk_known;
-
- spin_unlock_bh(&kp->smk_cipsolock);
- }
- rcu_read_unlock();
- if (final == NULL)
- final = smack_known_huh.smk_known;
- strncpy(result, final, SMK_MAXLEN);
- return;
-}
-
-/**
- * smack_to_cipso - find the CIPSO option to go with a Smack label
- * @smack: a pointer to the smack label in question
- * @cp: where to put the result
- *
- * Returns zero if a value is available, non-zero otherwise.
- */
-int smack_to_cipso(const char *smack, struct smack_cipso *cp)
-{
- struct smack_known *kp;
- int found = 0;
-
- rcu_read_lock();
- list_for_each_entry_rcu(kp, &smack_known_list, list) {
- if (kp->smk_known == smack ||
- strcmp(kp->smk_known, smack) == 0) {
- found = 1;
- break;
- }
- }
- rcu_read_unlock();
-
- if (found == 0 || kp->smk_cipso == NULL)
- return -ENOENT;
-
- memcpy(cp, kp->smk_cipso, sizeof(struct smack_cipso));
- return 0;
+ if (skp == NULL)
+ return 0;
+ return skp->smk_secid;
}
projects / platform / kernel / kernel-mfld-blackbay.git / blobdiff