Changeset 678 in openpam for trunk/lib/liboath/oath_key.c

Timestamp:

Mar 18, 2013, 9:34:29 PM (8 years ago)

Author:

Dag-Erling Smørgrav

Message:

Set a reasonable, hard limit on label length. This removes the need for
a variable-length key structure (to accommodate a variable-length label)
and vastly simplifies key parsing.

File:

• trunk/lib/liboath/oath_key.c (modified) (7 diffs)

trunk/lib/liboath/oath_key.c

@@ -57 +57 @@
  */
 struct oath_key *
-oath_key_alloc(size_t extra)
+oath_key_alloc(void)
 {
         struct oath_key *key;
 
-        if ((key = calloc(1, sizeof *key + extra)) == NULL) {
+        if ((key = calloc(1, sizeof *key)) == NULL) {
                 openpam_log(PAM_LOG_ERROR, "malloc(): %s", strerror(errno));
                 return (NULL);
         }
-        key->datalen = extra;
         /* XXX should try to wire */
         return (key);
@@ -78 +77 @@
 
         if (key != NULL) {
-                memset(key, 0, sizeof *key + key->datalen);
+                memset(key, 0, sizeof *key);
                 free(key);
         }
@@ -95 +94 @@
         char *e;
 
-        /*
-         * The URI string contains the label, the base32-encoded key and
-         * some fluff, so the combined length of the label and key can
-         * never exceed the length of the URI string.
-         */
-        if ((key = oath_key_alloc(strlen(uri))) == NULL)
+        if ((key = oath_key_alloc()) == NULL)
                 return (NULL);
 
@@ -124 +118 @@
         if ((q = strchr(p, '?')) == NULL)
                 goto invalid;
-        key->label = (char *)key->data;
-        key->labellen = (q - p) + 1;
+        if ((key->labellen = q - p + 1) > sizeof key->label)
+                goto invalid;
         memcpy(key->label, p, q - p);
         key->label[q - p] = '\0';
@@ -146 +140 @@
                                 /* dupe */
                                 goto invalid;
-                        /* base32-encoded key - multiple of 40 bits */
-                        if ((r - q) % 8 != 0 ||
-                            base32_declen(r - q) > OATH_MAX_KEYLEN)
-                                goto invalid;
-                        key->key = key->data + key->labellen;
-                        key->keylen = key->datalen - key->labellen;
+                        key->keylen = sizeof key->key;
                         if (base32_dec(q, r - q, key->key, &key->keylen) != 0)
                                 goto invalid;
@@ -315 +304 @@
         struct oath_key *key;
 
-        if ((key = oath_key_alloc(DUMMY_LABELLEN + DUMMY_KEYLEN)) == NULL)
+        if ((key = oath_key_alloc()) == NULL)
                 return (NULL);
         key->mode = mode;
@@ -322 +311 @@
         key->timestep = 30;
         key->hash = hash;
-        key->label = (char *)key->data;
         memcpy(key->label, DUMMY_LABEL, DUMMY_LABELLEN);
-        key->key = key->data + DUMMY_LABELLEN;
+        key->labellen = DUMMY_LABELLEN;
         key->keylen = DUMMY_KEYLEN;
         return (key);