+++ /dev/null
-/*
-
- silchmac.c
-
- Author: Pekka Riikonen <priikone@silcnet.org>
-
- Copyright (C) 1999 - 2008 Pekka Riikonen
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; version 2 of the License.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
-*/
-
-#include "silccrypto.h"
-
-/* HMAC context */
-struct SilcHmacStruct {
- SilcHmacObject *hmac;
- SilcHash hash;
- unsigned char inner_pad[64];
- unsigned char outer_pad[64];
- unsigned char *key;
- unsigned int key_len : 31;
- unsigned int allocated_hash : 1; /* TRUE if the hash was allocated */
-};
-
-#ifndef SILC_SYMBIAN
-/* List of dynamically registered HMACs. */
-SilcDList silc_hmac_list = NULL;
-#endif /* SILC_SYMBIAN */
-
-/* Default hmacs for silc_hmac_register_default(). */
-const SilcHmacObject silc_default_hmacs[] =
-{
- { "hmac-sha256-96", 12 },
- { "hmac-sha512-96", 12 },
- { "hmac-sha1-96", 12 },
- { "hmac-md5-96", 12 },
- { "hmac-sha256", 32 },
- { "hmac-sha512", 64 },
- { "hmac-sha1", 20 },
- { "hmac-md5", 16 },
-
- { NULL, 0 }
-};
-
-static void silc_hmac_init_internal(SilcHmac hmac, unsigned char *key,
- SilcUInt32 key_len)
-{
- SilcHash hash = hmac->hash;
- SilcUInt32 block_len;
- unsigned char hvalue[SILC_HASH_MAXLEN];
- int i;
-
- memset(hmac->inner_pad, 0, sizeof(hmac->inner_pad));
- memset(hmac->outer_pad, 0, sizeof(hmac->outer_pad));
-
- block_len = silc_hash_block_len(hash);
-
- /* If the key length is more than block size of the hash function, the
- key is hashed. */
- if (key_len > block_len) {
- silc_hash_make(hash, key, key_len, hvalue);
- key = hvalue;
- key_len = silc_hash_len(hash);
- }
-
- /* Copy the key into the pads */
- memcpy(hmac->inner_pad, key, key_len);
- memcpy(hmac->outer_pad, key, key_len);
-
- /* XOR the key with pads */
- for (i = 0; i < block_len; i++) {
- hmac->inner_pad[i] ^= 0x36;
- hmac->outer_pad[i] ^= 0x5c;
- }
-}
-
-/* Registers a new HMAC */
-
-SilcBool silc_hmac_register(const SilcHmacObject *hmac)
-{
-#ifndef SILC_SYMBIAN
- SilcHmacObject *new;
-
- SILC_LOG_DEBUG(("Registering new HMAC `%s'", hmac->name));
-
- /* Check for existing */
- if (silc_hmac_list) {
- SilcHmacObject *entry;
- silc_dlist_start(silc_hmac_list);
- while ((entry = silc_dlist_get(silc_hmac_list)) != SILC_LIST_END) {
- if (!strcmp(entry->name, hmac->name))
- return FALSE;
- }
- }
-
- new = silc_calloc(1, sizeof(*new));
- if (!new)
- return FALSE;
- 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);
-
-#endif /* SILC_SYMBIAN */
- return TRUE;
-}
-
-/* Unregister a HMAC */
-
-SilcBool silc_hmac_unregister(SilcHmacObject *hmac)
-{
-#ifndef SILC_SYMBIAN
- 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 (hmac == SILC_ALL_HMACS || entry == hmac) {
- silc_dlist_del(silc_hmac_list, entry);
- silc_free(entry->name);
- silc_free(entry);
-
- if (silc_dlist_count(silc_hmac_list) == 0) {
- silc_dlist_uninit(silc_hmac_list);
- silc_hmac_list = NULL;
- }
-
- return TRUE;
- }
- }
-
-#endif /* SILC_SYMBIAN */
- return FALSE;
-}
-
-/* Register default HMACs */
-
-SilcBool silc_hmac_register_default(void)
-{
- /* We use builtin HMACs */
- return TRUE;
-}
-
-/* Unregister all HMACs */
-
-SilcBool silc_hmac_unregister_all(void)
-{
-#ifndef SILC_SYMBIAN
- SilcHmacObject *entry;
-
- if (!silc_hmac_list)
- return FALSE;
-
- silc_dlist_start(silc_hmac_list);
- while ((entry = silc_dlist_get(silc_hmac_list)) != SILC_LIST_END) {
- silc_hmac_unregister(entry);
- if (!silc_hmac_list)
- break;
- }
-#endif /* SILC_SYMBIAN */
- return TRUE;
-}
-
-/* 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'. */
-
-SilcBool silc_hmac_alloc(const char *name, SilcHash hash, SilcHmac *new_hmac)
-{
- SilcHmacObject *entry = NULL;
- int i;
-
- SILC_LOG_DEBUG(("Allocating new HMAC"));
-
- /* Allocate the new object */
- *new_hmac = silc_calloc(1, sizeof(**new_hmac));
- if (!(*new_hmac))
- return FALSE;
-
- 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);
- silc_free(*new_hmac);
- *new_hmac = NULL;
- return FALSE;
- }
-
- (*new_hmac)->allocated_hash = TRUE;
- silc_free(tmp);
- }
-
- (*new_hmac)->hash = hash;
-
-#ifndef SILC_SYMBIAN
- /* Check registered list of HMACs */
- 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;
- }
- }
- }
-#endif /* SILC_SYMBIAN */
-
- if (!entry) {
- /* Check builtin list of HMACs */
- for (i = 0; silc_default_hmacs[i].name; i++) {
- if (!strcmp(silc_default_hmacs[i].name, name)) {
- (*new_hmac)->hmac = (SilcHmacObject *)&(silc_default_hmacs[i]);
- return TRUE;
- }
- }
- }
-
- silc_free(*new_hmac);
- *new_hmac = NULL;
- return FALSE;
-}
-
-/* Free's the SilcHmac object. */
-
-void silc_hmac_free(SilcHmac hmac)
-{
- if (hmac) {
- if (hmac->allocated_hash)
- silc_hash_free(hmac->hash);
-
- if (hmac->key) {
- memset(hmac->key, 0, hmac->key_len);
- silc_free(hmac->key);
- }
-
- silc_free(hmac);
- }
-}
-
-/* Returns the length of the MAC that the HMAC will produce. */
-
-SilcUInt32 silc_hmac_len(SilcHmac hmac)
-{
- return hmac->hmac->len;
-}
-
-/* Get hash context */
-
-SilcHash silc_hmac_get_hash(SilcHmac hmac)
-{
- return hmac->hash;
-}
-
-/* Return name of hmac */
-
-const char *silc_hmac_get_name(SilcHmac hmac)
-{
- return hmac->hmac->name;
-}
-
-/* Returns TRUE if HMAC `name' is supported. */
-
-SilcBool silc_hmac_is_supported(const char *name)
-{
- SilcHmacObject *entry;
- int i;
-
- if (!name)
- return FALSE;
-
-#ifndef SILC_SYMBIAN
- 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;
- }
- }
-#endif /* SILC_SYMBIAN */
-
- for (i = 0; silc_default_hmacs[i].name; i++)
- if (!strcmp(silc_default_hmacs[i].name, name))
- return TRUE;
-
- return FALSE;
-}
-
-/* Returns comma separated list of supported HMACs. */
-
-char *silc_hmac_get_supported()
-{
- SilcHmacObject *entry, *entry2;
- char *list = NULL;
- int len = 0, i;
-
-#ifndef SILC_SYMBIAN
- 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++;
- }
- }
-#endif /* SILC_SYMBIAN */
-
-
- for (i = 0; silc_default_hmacs[i].name; i++) {
- entry = (SilcHmacObject *)&(silc_default_hmacs[i]);
-
- if (silc_hmac_list) {
- silc_dlist_start(silc_hmac_list);
- while ((entry2 = silc_dlist_get(silc_hmac_list)) != SILC_LIST_END) {
- if (!strcmp(entry2->name, entry->name))
- break;
- }
- if (entry2)
- continue;
- }
-
- 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,
- SilcUInt32 key_len)
-{
- if (hmac->key) {
- memset(hmac->key, 0, hmac->key_len);
- silc_free(hmac->key);
- }
- hmac->key = silc_malloc(key_len);
- if (!hmac->key)
- return;
- hmac->key_len = key_len;
- memcpy(hmac->key, key, key_len);
-}
-
-/* Return HMAC key */
-
-const unsigned char *silc_hmac_get_key(SilcHmac hmac, SilcUInt32 *key_len)
-{
- if (key_len)
- *key_len = hmac->key_len;
- return (const unsigned char *)hmac->key;
-}
-
-/* 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,
- SilcUInt32 data_len, unsigned char *return_hash,
- SilcUInt32 *return_len)
-{
- SILC_LOG_DEBUG(("Making HMAC for message"));
-
- silc_hmac_init(hmac);
- silc_hmac_update(hmac, data, data_len);
- silc_hmac_final(hmac, return_hash, return_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,
- SilcUInt32 data_len,
- unsigned char *key, SilcUInt32 key_len,
- unsigned char *return_hash,
- SilcUInt32 *return_len)
-{
- SILC_LOG_DEBUG(("Making HMAC for message"));
-
- silc_hmac_init_with_key(hmac, key, key_len);
- silc_hmac_update(hmac, data, data_len);
- silc_hmac_final(hmac, return_hash, return_len);
-}
-
-/* Creates the HMAC just as above except that the hash value is truncated
- to the truncated_len sent as argument. NOTE: One should not truncate to
- less than half of the length of original hash value. However, this
- routine allows these dangerous truncations. */
-
-void silc_hmac_make_truncated(SilcHmac hmac, unsigned char *data,
- SilcUInt32 data_len,
- SilcUInt32 truncated_len,
- unsigned char *return_hash)
-{
- unsigned char hvalue[SILC_HASH_MAXLEN];
-
- SILC_LOG_DEBUG(("Making HMAC for message"));
-
- silc_hmac_init(hmac);
- silc_hmac_update(hmac, data, data_len);
- silc_hmac_final(hmac, return_hash, NULL);
- memcpy(return_hash, hvalue, truncated_len);
- memset(hvalue, 0, sizeof(hvalue));
-}
-
-/* Init HMAC for silc_hmac_update and silc_hmac_final. */
-
-void silc_hmac_init(SilcHmac hmac)
-{
- silc_hmac_init_with_key(hmac, hmac->key, hmac->key_len);
-}
-
-/* Same as above but with specific key */
-
-void silc_hmac_init_with_key(SilcHmac hmac, const unsigned char *key,
- SilcUInt32 key_len)
-{
- SilcHash hash = hmac->hash;
- silc_hmac_init_internal(hmac, (unsigned char *)key, key_len);
- silc_hash_init(hash);
- silc_hash_update(hash, hmac->inner_pad, silc_hash_block_len(hash));
-}
-
-/* Add data to be used in the MAC computation. */
-
-void silc_hmac_update(SilcHmac hmac, const unsigned char *data,
- SilcUInt32 data_len)
-{
- SilcHash hash = hmac->hash;
- silc_hash_update(hash, data, data_len);
-}
-
-/* Compute the final MAC. */
-
-void silc_hmac_final(SilcHmac hmac, unsigned char *return_hash,
- SilcUInt32 *return_len)
-{
- SilcHash hash = hmac->hash;
- unsigned char mac[SILC_HASH_MAXLEN];
-
- silc_hash_final(hash, mac);
- silc_hash_init(hash);
- silc_hash_update(hash, hmac->outer_pad, silc_hash_block_len(hash));
- silc_hash_update(hash, mac, silc_hash_len(hash));
- silc_hash_final(hash, mac);
- memcpy(return_hash, mac, hmac->hmac->len);
- memset(mac, 0, sizeof(mac));
-
- if (return_len)
- *return_len = hmac->hmac->len;
-}
projects / crypto.git / blobdiff