void silc_client_send_channel_message(SilcClient client,
SilcClientConnection conn,
SilcChannelEntry channel,
+ SilcChannelPrivateKey key,
+ SilcMessageFlags flags,
unsigned char *data,
- unsigned int data_len,
+ uint32 data_len,
int force_send)
{
int i;
SilcCipher cipher;
SilcHmac hmac;
unsigned char *id_string;
- unsigned int iv_len;
+ uint32 iv_len;
SILC_LOG_DEBUG(("Sending packet to channel"));
- if (!channel || !channel->key || !channel->hmac) {
- client->ops->say(client, conn,
- "Cannot talk to channel: key does not exist");
- return;
+ /* Take the key to be used */
+ if (channel->mode & SILC_CHANNEL_MODE_PRIVKEY) {
+ if (key) {
+ /* Use key application specified */
+ cipher = key->cipher;
+ hmac = key->hmac;
+ } else if (channel->curr_key) {
+ /* Use current private key */
+ cipher = channel->curr_key->cipher;
+ hmac = channel->curr_key->hmac;
+ } else if (!channel->curr_key && channel->private_keys) {
+ /* Use just some private key since we don't know what to use
+ and private keys are set. */
+ silc_dlist_start(channel->private_keys);
+ key = silc_dlist_get(channel->private_keys);
+ cipher = key->cipher;
+ hmac = key->hmac;
+
+ /* Use this key as current private key */
+ channel->curr_key = key;
+ } else {
+ /* Use normal channel key generated by the server */
+ cipher = channel->channel_key;
+ hmac = channel->hmac;
+ }
+ } else {
+ /* Use normal channel key generated by the server */
+ cipher = channel->channel_key;
+ hmac = channel->hmac;
}
+ if (!cipher || !hmac)
+ return;
+
/* Generate IV */
- iv_len = silc_cipher_get_block_len(channel->channel_key);
+ iv_len = silc_cipher_get_block_len(cipher);
if (channel->iv[0] == '\0')
for (i = 0; i < iv_len; i++) channel->iv[i] =
silc_rng_get_byte(client->rng);
silc_hash_make(client->md5hash, channel->iv, iv_len, channel->iv);
/* Encode the channel payload. This also encrypts the message payload. */
- payload = silc_channel_payload_encode(data_len, data, iv_len,
- channel->iv, channel->channel_key,
- channel->hmac, client->rng);
+ payload = silc_channel_message_payload_encode(flags, data_len, data, iv_len,
+ channel->iv, cipher, hmac);
/* Get data used in packet header encryption, keys and stuff. */
cipher = conn->send_key;
- hmac = conn->hmac;
+ hmac = conn->hmac_send;
id_string = silc_id_id2str(channel->id, SILC_ID_CHANNEL);
/* Set the packet context pointers. The destination ID is always
packetdata.flags = 0;
packetdata.type = SILC_PACKET_CHANNEL_MESSAGE;
packetdata.src_id = conn->local_id_data;
- packetdata.src_id_len = SILC_ID_CLIENT_LEN;
+ packetdata.src_id_len = silc_id_get_len(conn->local_id, SILC_ID_CLIENT);
packetdata.src_id_type = SILC_ID_CLIENT;
packetdata.dst_id = id_string;
- packetdata.dst_id_len = SILC_ID_CHANNEL_LEN;
+ packetdata.dst_id_len = silc_id_get_len(channel->id, SILC_ID_CHANNEL);
packetdata.dst_id_type = SILC_ID_CHANNEL;
packetdata.truelen = payload->len + SILC_PACKET_HEADER_LEN +
packetdata.src_id_len + packetdata.dst_id_len;
silc_free(id_string);
}
+static void silc_client_channel_message_cb(SilcClient client,
+ SilcClientConnection conn,
+ SilcClientEntry *clients,
+ uint32 clients_count,
+ void *context)
+{
+ SilcPacketContext *packet = (SilcPacketContext *)context;
+
+ if (clients)
+ silc_client_channel_message(client, conn->sock, packet);
+ silc_packet_context_free(packet);
+}
+
/* Process received message to a channel (or from a channel, really). This
decrypts the channel message with channel specific key and parses the
channel payload. Finally it displays the message on the screen. */
{
SilcClientConnection conn = (SilcClientConnection)sock->user_data;
SilcBuffer buffer = packet->buffer;
- SilcChannelPayload payload = NULL;
+ SilcChannelMessagePayload payload = NULL;
SilcChannelID *id = NULL;
SilcChannelEntry channel;
SilcChannelUser chu;
SilcIDCacheEntry id_cache = NULL;
SilcClientID *client_id = NULL;
- int found = FALSE;
+ bool found = FALSE;
unsigned char *message;
SILC_LOG_DEBUG(("Start"));
goto out;
/* Find the channel entry from channels on this connection */
- if (!silc_idcache_find_by_id_one(conn->channel_cache, (void *)id,
- SILC_ID_CHANNEL, &id_cache))
+ if (!silc_idcache_find_by_id_one(conn->channel_cache, (void *)id, &id_cache))
goto out;
channel = (SilcChannelEntry)id_cache->context;
- /* Parse the channel message payload. This also decrypts the payload */
- payload = silc_channel_payload_parse(buffer, channel->channel_key,
- channel->hmac);
- if (!payload)
+ /* If there is no channel private key then just decrypt the message
+ with the channel key. If private keys are set then just go through
+ all private keys and check what decrypts correctly. */
+ if (!(channel->mode & SILC_CHANNEL_MODE_PRIVKEY)) {
+ /* Parse the channel message payload. This also decrypts the payload */
+ payload = silc_channel_message_payload_parse(buffer, channel->channel_key,
+ channel->hmac);
+
+ /* If decryption failed and we have just performed channel key rekey
+ we will use the old key in decryption. If that fails too then we
+ cannot do more and will drop the packet. */
+ if (!payload) {
+ if (!channel->old_channel_key)
+ goto out;
+
+ payload = silc_channel_message_payload_parse(buffer,
+ channel->old_channel_key,
+ channel->old_hmac);
+ if (!payload)
+ goto out;
+ }
+ } else if (channel->private_keys) {
+ SilcChannelPrivateKey entry;
+
+ silc_dlist_start(channel->private_keys);
+ while ((entry = silc_dlist_get(channel->private_keys)) != SILC_LIST_END) {
+ /* Parse the channel message payload. This also decrypts the payload */
+ payload = silc_channel_message_payload_parse(buffer, entry->cipher,
+ entry->hmac);
+ if (payload)
+ break;
+ }
+ if (entry == SILC_LIST_END)
+ goto out;
+ } else {
goto out;
-
- message = silc_channel_get_data(payload, NULL);
+ }
/* Find client entry */
silc_list_start(channel->clients);
while ((chu = silc_list_get(channel->clients)) != SILC_LIST_END) {
- if (!SILC_ID_CLIENT_COMPARE(chu->client->id, client_id)) {
+ if (SILC_ID_CLIENT_COMPARE(chu->client->id, client_id)) {
found = TRUE;
break;
}
}
+ if (!found) {
+ /* Resolve the client info */
+ silc_client_get_client_by_id_resolve(client, conn, client_id,
+ silc_client_channel_message_cb,
+ silc_packet_context_dup(packet));
+ goto out;
+ }
+
+ message = silc_channel_message_get_data(payload, NULL);
+
/* Pass the message to application */
- client->ops->channel_message(client, conn, found ? chu->client : NULL,
- channel, message);
+ client->ops->channel_message(client, conn, chu->client, channel,
+ silc_channel_message_get_flags(payload),
+ message);
out:
if (id)
if (client_id)
silc_free(client_id);
if (payload)
- silc_channel_payload_free(payload);
+ silc_channel_message_payload_free(payload);
+}
+
+/* Timeout callback that is called after a short period of time after the
+ new channel key has been created. This removes the old channel key all
+ together. */
+
+SILC_TASK_CALLBACK(silc_client_save_channel_key_rekey)
+{
+ SilcChannelEntry channel = (SilcChannelEntry)context;
+
+ if (channel->old_channel_key)
+ silc_cipher_free(channel->old_channel_key);
+ if (channel->old_hmac)
+ silc_hmac_free(channel->old_hmac);
+ channel->old_channel_key = NULL;
+ channel->old_hmac = NULL;
+ channel->rekey_task = NULL;
}
/* Saves channel key from encoded `key_payload'. This is used when we
SilcBuffer key_payload,
SilcChannelEntry channel)
{
- unsigned char *id_string, *key, *cipher, hash[32];
- unsigned int tmp_len;
+ unsigned char *id_string, *key, *cipher, *hmac, hash[32];
+ uint32 tmp_len;
SilcChannelID *id;
SilcIDCacheEntry id_cache = NULL;
SilcChannelKeyPayload payload;
/* Find channel. */
if (!channel) {
- if (!silc_idcache_find_by_id_one(conn->channel_cache, (void *)id,
- SILC_ID_CHANNEL, &id_cache))
+ if (!silc_idcache_find_by_id_one(conn->channel_cache,
+ (void *)id, &id_cache))
goto out;
/* Get channel entry */
channel = (SilcChannelEntry)id_cache->context;
}
+ hmac = channel->hmac ? channel->hmac->hmac->name : SILC_DEFAULT_HMAC;
+
+ /* Save the old key for a short period of time so that we can decrypt
+ channel message even after the rekey if some client would be sending
+ messages with the old key after the rekey. */
+ if (channel->old_channel_key)
+ silc_cipher_free(channel->old_channel_key);
+ if (channel->old_hmac)
+ silc_hmac_free(channel->old_hmac);
+ if (channel->rekey_task)
+ silc_schedule_task_del(conn->client->schedule, channel->rekey_task);
+ channel->old_channel_key = channel->channel_key;
+ channel->old_hmac = channel->hmac;
+ channel->rekey_task =
+ silc_schedule_task_add(conn->client->schedule, 0,
+ silc_client_save_channel_key_rekey, channel,
+ 10, 0, SILC_TASK_TIMEOUT, SILC_TASK_PRI_NORMAL);
+
+ /* Free the old channel key data */
+ silc_free(channel->key);
+
/* Save the key */
key = silc_channel_key_get_key(payload, &tmp_len);
cipher = silc_channel_key_get_cipher(payload, NULL);
memcpy(channel->key, key, tmp_len);
if (!silc_cipher_alloc(cipher, &channel->channel_key)) {
- conn->client->ops->say(conn->client, conn,
- "Cannot talk to channel: unsupported cipher %s", cipher);
+ conn->client->ops->say(conn->client, conn, SILC_CLIENT_MESSAGE_AUDIT,
+ "Cannot talk to channel: unsupported cipher %s",
+ cipher);
goto out;
}
silc_cipher_set_key(channel->channel_key, key, channel->key_len);
/* Generate HMAC key from the channel key data and set it */
- if (!channel->hmac)
- silc_hmac_alloc("hmac-sha1-96", NULL, &channel->hmac);
+ silc_hmac_alloc(hmac, NULL, &channel->hmac);
silc_hash_make(channel->hmac->hash, key, tmp_len, hash);
silc_hmac_set_key(channel->hmac, hash, silc_hash_len(channel->hmac->hash));
memset(hash, 0, sizeof(hash));
- /* Client is now joined to the channel */
- channel->on_channel = TRUE;
-
out:
silc_free(id);
silc_channel_key_payload_free(payload);
encrypted using that key. All clients on the channel must also know the
key in order to decrypt the messages. However, it is possible to have
several private keys per one channel. In this case only some of the
- clients on the channel may now the one key and only some the other key.
+ clients on the channel may know the one key and only some the other key.
+
+ If `cipher' and/or `hmac' is NULL then default values will be used
+ (aes-256-cbc for cipher and hmac-sha1-96 for hmac).
The private key for channel is optional. If it is not set then the
channel messages are encrypted using the channel key generated by the
SilcClientConnection conn,
SilcChannelEntry channel,
char *cipher,
+ char *hmac,
unsigned char *key,
- unsigned int key_len)
+ uint32 key_len)
{
+ SilcChannelPrivateKey entry;
+ unsigned char hash[32];
+ SilcSKEKeyMaterial *keymat;
+
+ if (!(channel->mode & SILC_CHANNEL_MODE_PRIVKEY))
+ return FALSE;
+
+ if (!cipher)
+ cipher = SILC_DEFAULT_CIPHER;
+ if (!hmac)
+ hmac = SILC_DEFAULT_HMAC;
+
+ if (!silc_cipher_is_supported(cipher))
+ return FALSE;
+
+ if (!silc_hmac_is_supported(hmac))
+ return FALSE;
+
+ /* Produce the key material */
+ keymat = silc_calloc(1, sizeof(*keymat));
+ if (silc_ske_process_key_material_data(key, key_len, 16, 256, 16,
+ client->md5hash, keymat)
+ != SILC_SKE_STATUS_OK)
+ return FALSE;
+
+ /* Remove the current key, if it exists. */
+ if (channel->channel_key) {
+ silc_cipher_free(channel->channel_key);
+ memset(channel->key, 0, channel->key_len / 8);
+ silc_free(channel->key);
+ channel->channel_key = NULL;
+ channel->key = NULL;
+ channel->key_len = 0;
+ }
+ if (channel->hmac) {
+ silc_hmac_free(channel->hmac);
+ channel->hmac = NULL;
+ }
+
+ if (!channel->private_keys)
+ channel->private_keys = silc_dlist_init();
+
+ /* Save the key */
+ entry = silc_calloc(1, sizeof(*entry));
+ entry->key = silc_calloc(keymat->enc_key_len / 8, sizeof(*entry->key));
+ memcpy(entry->key, keymat->send_enc_key, keymat->enc_key_len / 8);
+ entry->key_len = keymat->enc_key_len / 8;
+
+ /* Allocate the cipher and set the key*/
+ silc_cipher_alloc(cipher, &entry->cipher);
+ silc_cipher_set_key(entry->cipher, entry->key, keymat->enc_key_len);
+
+ /* Generate HMAC key from the channel key data and set it */
+ silc_hmac_alloc(hmac, NULL, &entry->hmac);
+ silc_hash_make(entry->hmac->hash, entry->key, entry->key_len, hash);
+ silc_hmac_set_key(entry->hmac, hash, silc_hash_len(entry->hmac->hash));
+ memset(hash, 0, sizeof(hash));
+
+ /* Add to the private keys list */
+ silc_dlist_add(channel->private_keys, entry);
+
+ if (!channel->curr_key)
+ channel->curr_key = entry;
+
+ /* Free the key material */
+ silc_ske_free_key_material(keymat);
return TRUE;
}
SilcClientConnection conn,
SilcChannelEntry channel)
{
+ SilcChannelPrivateKey entry;
+
+ if (!channel->private_keys)
+ return FALSE;
+
+ silc_dlist_start(channel->private_keys);
+ while ((entry = silc_dlist_get(channel->private_keys)) != SILC_LIST_END) {
+ silc_dlist_del(channel->private_keys, entry);
+ memset(entry->key, 0, entry->key_len);
+ silc_free(entry->key);
+ silc_cipher_free(entry->cipher);
+ silc_hmac_free(entry->hmac);
+ silc_free(entry);
+ }
+
+ channel->curr_key = NULL;
+
+ silc_dlist_uninit(channel->private_keys);
+ channel->private_keys = NULL;
return TRUE;
}
SilcChannelEntry channel,
SilcChannelPrivateKey key)
{
+ SilcChannelPrivateKey entry;
+
+ if (!channel->private_keys)
+ return FALSE;
+
+ silc_dlist_start(channel->private_keys);
+ while ((entry = silc_dlist_get(channel->private_keys)) != SILC_LIST_END) {
+ if (entry == key) {
+ if (channel->curr_key == entry)
+ channel->curr_key = NULL;
+
+ silc_dlist_del(channel->private_keys, entry);
+ memset(entry->key, 0, entry->key_len);
+ silc_free(entry->key);
+ silc_cipher_free(entry->cipher);
+ silc_hmac_free(entry->hmac);
+ silc_free(entry);
+
+ if (silc_dlist_count(channel->private_keys) == 0) {
+ silc_dlist_uninit(channel->private_keys);
+ channel->private_keys = NULL;
+ }
+
+ return TRUE;
+ }
+ }
- return TRUE;
+ return FALSE;
}
/* Returns array (pointers) of private keys associated to the `channel'.
silc_client_list_channel_private_keys(SilcClient client,
SilcClientConnection conn,
SilcChannelEntry channel,
- unsigned int *key_count)
+ uint32 *key_count)
{
+ SilcChannelPrivateKey *keys = NULL, entry;
+ uint32 count = 0;
+
+ if (!channel->private_keys)
+ return NULL;
+
+ silc_dlist_start(channel->private_keys);
+ while ((entry = silc_dlist_get(channel->private_keys)) != SILC_LIST_END) {
+ keys = silc_realloc(keys, sizeof(*keys) * (count + 1));
+ keys[count] = entry;
+ count++;
+ }
+
+ if (key_count)
+ *key_count = count;
- return NULL;
+ return keys;
}
/* Frees the SilcChannelPrivateKey array. */
void silc_client_free_channel_private_keys(SilcChannelPrivateKey *keys,
- unsigned int key_count)
+ uint32 key_count)
{
-
+ silc_free(keys);
}
projects / silc.git / blobdiff