#include "silcincludes.h"
-/* Allocates a new SilcHmac object. First argument is the hash function
- object to tell the hmac which hash function should be used when creating
- HMAC's. The new SilcHmac object is returned to new_hmac argument. */
+/* List of dynamically registered HMACs. */
+SilcDList silc_hmac_list = NULL;
-int silc_hmac_alloc(SilcHash hash, SilcHmac *new_hmac)
+/* Registers a new HMAC into the SILC. This function is used at the
+ initialization of the SILC. */
+
+int silc_hmac_register(SilcHmacObject *hmac)
+{
+ SilcHmacObject *new;
+
+ SILC_LOG_DEBUG(("Registering new HMAC `%s'", hmac->name));
+
+ new = silc_calloc(1, sizeof(*new));
+ new->name = strdup(hmac->name);
+ new->len = hmac->len;
+
+ /* Add to list */
+ if (silc_hmac_list == NULL)
+ silc_hmac_list = silc_dlist_init();
+ silc_dlist_add(silc_hmac_list, new);
+
+ return TRUE;
+}
+
+/* Unregister a HMAC from the SILC. */
+
+int silc_hmac_unregister(SilcHmacObject *hmac)
{
- SILC_LOG_DEBUG(("Allocating new hmac object"));
+ SilcHmacObject *entry;
+
+ SILC_LOG_DEBUG(("Unregistering HMAC"));
+
+ if (!silc_hmac_list)
+ return FALSE;
+ silc_dlist_start(silc_hmac_list);
+ while ((entry = silc_dlist_get(silc_hmac_list)) != SILC_LIST_END) {
+ if (entry == hmac) {
+ silc_dlist_del(silc_hmac_list, entry);
+
+ if (silc_dlist_count(silc_hmac_list) == 0) {
+ silc_dlist_uninit(silc_hmac_list);
+ silc_hmac_list = NULL;
+ }
+
+ return TRUE;
+ }
+ }
+
+ return FALSE;
+}
+
+/* Allocates a new SilcHmac object of name of `name'. The `hash' may
+ be provided as argument. If provided it is used as the hash function
+ of the HMAC. If it is NULL then the hash function is allocated and
+ the name of the hash algorithm is derived from the `name'. */
+
+int silc_hmac_alloc(char *name, SilcHash hash, SilcHmac *new_hmac)
+{
+ SilcHmacObject *entry;
+
+ SILC_LOG_DEBUG(("Allocating new HMAC"));
+
+ /* Allocate the new object */
*new_hmac = silc_calloc(1, sizeof(**new_hmac));
+
+ if (!hash) {
+ char *tmp = strdup(name), *hname;
+
+ hname = tmp;
+ if (strchr(hname, '-'))
+ hname = strchr(hname, '-') + 1;
+ if (strchr(hname, '-'))
+ *strchr(hname, '-') = '\0';
+
+ if (!silc_hash_alloc(hname, &hash)) {
+ silc_free(tmp);
+ return FALSE;
+ }
+
+ (*new_hmac)->allocated_hash = TRUE;
+ silc_free(tmp);
+ }
+
(*new_hmac)->hash = hash;
- (*new_hmac)->set_key = silc_hmac_set_key;
- (*new_hmac)->make_hmac = silc_hmac_make;
- (*new_hmac)->make_hmac_with_key = silc_hmac_make_with_key;
- (*new_hmac)->make_hmac_truncated = silc_hmac_make_truncated;
- return TRUE;
+ if (silc_hmac_list) {
+ silc_dlist_start(silc_hmac_list);
+ while ((entry = silc_dlist_get(silc_hmac_list)) != SILC_LIST_END) {
+ if (!strcmp(entry->name, name)) {
+ (*new_hmac)->hmac = entry;
+ return TRUE;
+ }
+ }
+ }
+
+ return FALSE;
}
/* Free's the SilcHmac object. */
void silc_hmac_free(SilcHmac hmac)
{
- if (hmac)
+ if (hmac) {
+ if (hmac->allocated_hash)
+ silc_hash_free(hmac->hash);
silc_free(hmac);
+ }
+}
+
+/* Returns the length of the MAC that the HMAC will produce. */
+
+unsigned int silc_hmac_len(SilcHmac hmac)
+{
+ return hmac->hmac->len;
+}
+
+/* Returns TRUE if HMAC `name' is supported. */
+
+int silc_hmac_is_supported(const char *name)
+{
+ SilcHmacObject *entry;
+
+ if (!name)
+ return FALSE;
+
+ if (silc_hmac_list) {
+ silc_dlist_start(silc_hmac_list);
+ while ((entry = silc_dlist_get(silc_hmac_list)) != SILC_LIST_END) {
+ if (!strcmp(entry->name, name))
+ return TRUE;
+ }
+ }
+
+ return FALSE;
+}
+
+/* Returns comma separated list of supported HMACs. */
+
+char *silc_hmac_get_supported()
+{
+ SilcHmacObject *entry;
+ char *list = NULL;
+ int len;
+
+ len = 0;
+ if (silc_hmac_list) {
+ silc_dlist_start(silc_hmac_list);
+ while ((entry = silc_dlist_get(silc_hmac_list)) != SILC_LIST_END) {
+ len += strlen(entry->name);
+ list = silc_realloc(list, len + 1);
+
+ memcpy(list + (len - strlen(entry->name)),
+ entry->name, strlen(entry->name));
+ memcpy(list + len, ",", 1);
+ len++;
+ }
+ }
+
+ list[len - 1] = 0;
+
+ return list;
+}
+
+/* Sets the HMAC key used in the HMAC creation */
+
+void silc_hmac_set_key(SilcHmac hmac, const unsigned char *key,
+ unsigned int key_len)
+{
+ hmac->key = silc_calloc(key_len, sizeof(unsigned char));
+ hmac->key_len = key_len;
+ memcpy(hmac->key, key, key_len);
}
/* Creates the HMAC. The created keyed hash value is returned to
unsigned char inner_pad[hash->hash->block_len + 1];
unsigned char outer_pad[hash->hash->block_len + 1];
unsigned char hvalue[hash->hash->hash_len];
+ unsigned char mac[128];
void *hash_context;
int i;
/* If the key length is more than block size of the hash function, the
key is hashed. */
if (key_len > hash->hash->block_len) {
- hash->make_hash(hash, key, key_len, hvalue);
+ silc_hash_make(hash, key, key_len, hvalue);
key = hvalue;
key_len = hash->hash->hash_len;
}
hash->hash->init(hash_context);
hash->hash->update(hash_context, inner_pad, hash->hash->block_len);
hash->hash->update(hash_context, data, data_len);
- hash->hash->final(hash_context, return_hash);
+ hash->hash->final(hash_context, mac);
hash->hash->init(hash_context);
hash->hash->update(hash_context, outer_pad, hash->hash->block_len);
- hash->hash->update(hash_context, return_hash, hash->hash->hash_len);
- hash->hash->final(hash_context, return_hash);
+ hash->hash->update(hash_context, mac, hash->hash->hash_len);
+ hash->hash->final(hash_context, mac);
+ memcpy(return_hash, mac, hmac->hmac->len);
+ memset(mac, 0, sizeof(mac));
}
/* Create the HMAC. This is thee make_hmac function pointer. This
uses the internal key set with silc_hmac_set_key. */
void silc_hmac_make(SilcHmac hmac, unsigned char *data,
- unsigned int data_len, unsigned char *return_hash)
+ unsigned int data_len, unsigned char *return_hash,
+ unsigned int *return_len)
{
silc_hmac_make_internal(hmac, data, data_len, hmac->key,
hmac->key_len, return_hash);
+ if (return_len)
+ *return_len = hmac->hmac->len;
+}
+
+/* Creates HMAC just as above except that this doesn't use the internal
+ key. The key is sent as argument to the function. */
+
+void silc_hmac_make_with_key(SilcHmac hmac, unsigned char *data,
+ unsigned int data_len,
+ unsigned char *key, unsigned int key_len,
+ unsigned char *return_hash,
+ unsigned int *return_len)
+{
+ silc_hmac_make_internal(hmac, data, data_len, key, key_len, return_hash);
+ if (return_len)
+ *return_len = hmac->hmac->len;
}
/* Creates the HMAC just as above except that the hash value is truncated
memcpy(return_hash, hvalue, truncated_len);
memset(hvalue, 0, sizeof(hvalue));
}
-
-/* Creates HMAC just as above except that this doesn't use the internal
- key. The key is sent as argument to the function. */
-
-void silc_hmac_make_with_key(SilcHmac hmac, unsigned char *data,
- unsigned int data_len,
- unsigned char *key, unsigned int key_len,
- unsigned char *return_hash)
-{
- silc_hmac_make_internal(hmac, data, data_len, key, key_len, return_hash);
-}
-
-/* Sets the HMAC key used in the HMAC creation */
-
-void silc_hmac_set_key(SilcHmac hmac, const unsigned char *key,
- unsigned int key_len)
-{
- hmac->key = silc_calloc(key_len, sizeof(unsigned char));
- hmac->key_len = key_len;
- memcpy(hmac->key, key, key_len);
-}