Added checking for maximum packet length.

[silc.git] / lib / silccore / silcpacket.c

diff --git a/lib/silccore/silcpacket.c b/lib/silccore/silcpacket.c
index 76c36ff886c23bf95448b85eda1dc6d9d8de568d..16124e29ea75bd9224ca9347b93968ddfe1844ca 100644 (file)
--- a/lib/silccore/silcpacket.c
+++ b/lib/silccore/silcpacket.c
@@ -77,11 +77,11 @@ int silc_packet_send(SilcSocketConnection sock, bool force_send)
    other process of HMAC computing and encryption is needed this function
    cannot be used. */
 
-void silc_packet_encrypt(SilcCipher cipher, SilcHmac hmac, uint32 sequence,
-                        SilcBuffer buffer, uint32 len)
+void silc_packet_encrypt(SilcCipher cipher, SilcHmac hmac, SilcUInt32 sequence,
+                        SilcBuffer buffer, SilcUInt32 len)
 {
   unsigned char mac[32];
-  uint32 mac_len;
+  SilcUInt32 mac_len;
 
   /* Compute HMAC. This assumes that HMAC is created from the entire
      data area thus this uses the length found in buffer, not the length
@@ -169,9 +169,14 @@ void silc_packet_assemble(SilcPacketContext *ctx, SilcCipher cipher)
   /* Get the true length of the packet. This is saved as payload length
      into the packet header. This does not include the length of the
      padding. */
-  if (!ctx->truelen)
+  if (!ctx->truelen) {
     ctx->truelen = ctx->buffer->len + SILC_PACKET_HEADER_LEN + 
       ctx->src_id_len + ctx->dst_id_len;
+    if (ctx->truelen > SILC_PACKET_MAX_LEN) {
+      ctx->truelen -= (SILC_PACKET_MAX_LEN - ctx->truelen);
+      silc_buffer_push_tail(ctx->buffer, (SILC_PACKET_MAX_LEN - ctx->truelen));
+    }
+  }
 
   /* Calculate the length of the padding. The padding is calculated from
      the data that will be encrypted. */
@@ -224,9 +229,9 @@ void silc_packet_assemble(SilcPacketContext *ctx, SilcCipher cipher)
    outgoing buffer in SilcSocketConnection object. */
 
 void silc_packet_send_prepare(SilcSocketConnection sock,
-                             uint32 header_len,
-                             uint32 padlen,
-                             uint32 data_len)
+                             SilcUInt32 header_len,
+                             SilcUInt32 padlen,
+                             SilcUInt32 data_len)
 {
   int totlen, oldlen;
 
@@ -284,7 +289,7 @@ void silc_packet_send_prepare(SilcSocketConnection sock,
 ******************************************************************************/
 
 static int silc_packet_decrypt(SilcCipher cipher, SilcHmac hmac, 
-                              uint32 sequence, SilcBuffer buffer, 
+                              SilcUInt32 sequence, SilcBuffer buffer, 
                               bool normal);
 
 /* Receives packet from network and reads the data into connection's
@@ -327,7 +332,7 @@ int silc_packet_receive(SilcSocketConnection sock)
 bool silc_packet_receive_process(SilcSocketConnection sock,
                                 bool local_is_router,
                                 SilcCipher cipher, SilcHmac hmac,
-                                uint32 sequence,
+                                SilcUInt32 sequence,
                                 SilcPacketParserCallback parser,
                                 void *parser_context)
 {
@@ -377,6 +382,8 @@ bool silc_packet_receive_process(SilcSocketConnection sock,
 
     SILC_UNSET_INBUF_PENDING(sock);
     parse_ctx = silc_calloc(1, sizeof(*parse_ctx));
+    if (!parse_ctx)
+      return FALSE;
     parse_ctx->packet = silc_packet_context_alloc();
     parse_ctx->packet->buffer = silc_buffer_alloc(paddedlen + mac_len);
     parse_ctx->packet->type = sock->inbuf->data[3];
@@ -445,12 +452,12 @@ bool silc_packet_receive_process(SilcSocketConnection sock,
    after packet has been totally decrypted and parsed. */
 
 static int silc_packet_check_mac(SilcHmac hmac, SilcBuffer buffer,
-                                uint32 sequence)
+                                SilcUInt32 sequence)
 {
   /* Check MAC */
   if (hmac) {
     unsigned char mac[32], psn[4];
-    uint32 mac_len;
+    SilcUInt32 mac_len;
     
     SILC_LOG_DEBUG(("Verifying MAC"));
 
@@ -523,7 +530,7 @@ static int silc_packet_decrypt_rest_special(SilcCipher cipher,
 {
   /* Decrypt rest of the header plus padding */
   if (cipher) {
-    uint16 len;
+    SilcUInt16 len;
 
     /* Pull MAC from packet before decryption */
     if (hmac) {
@@ -539,8 +546,8 @@ static int silc_packet_decrypt_rest_special(SilcCipher cipher,
 
     /* padding length + src id len + dst id len + header length - 16
        bytes already decrypted, gives the rest of the encrypted packet */
-    len = (((uint8)buffer->data[4] + (uint8)buffer->data[6] + 
-          (uint8)buffer->data[7] + SILC_PACKET_HEADER_LEN) -
+    len = (((SilcUInt8)buffer->data[4] + (SilcUInt8)buffer->data[6] + 
+          (SilcUInt8)buffer->data[7] + SILC_PACKET_HEADER_LEN) -
           SILC_PACKET_MIN_HEADER_LEN);
 
     silc_buffer_pull(buffer, SILC_PACKET_MIN_HEADER_LEN);
@@ -573,7 +580,7 @@ static int silc_packet_decrypt_rest_special(SilcCipher cipher,
    is special and requires special procesing. */
 
 static int silc_packet_decrypt(SilcCipher cipher, SilcHmac hmac,
-                              uint32 sequence, SilcBuffer buffer, 
+                              SilcUInt32 sequence, SilcBuffer buffer, 
                               bool normal)
 {
   /* If the packet type is not any special type lets decrypt rest
@@ -611,7 +618,7 @@ static int silc_packet_decrypt(SilcCipher cipher, SilcHmac hmac,
 SilcPacketType silc_packet_parse(SilcPacketContext *ctx, SilcCipher cipher)
 {
   SilcBuffer buffer = ctx->buffer;
-  uint8 tmp;
+  SilcUInt8 tmp;
   int len, ret;
 
   SILC_LOG_DEBUG(("Parsing incoming packet"));
@@ -679,7 +686,7 @@ SilcPacketType silc_packet_parse_special(SilcPacketContext *ctx,
                                         SilcCipher cipher)
 {
   SilcBuffer buffer = ctx->buffer;
-  uint8 tmp;
+  SilcUInt8 tmp;
   int len, ret;
 
   SILC_LOG_DEBUG(("Parsing incoming packet"));
@@ -746,6 +753,8 @@ SilcPacketType silc_packet_parse_special(SilcPacketContext *ctx,
 SilcPacketContext *silc_packet_context_alloc(void)
 {
   SilcPacketContext *ctx = silc_calloc(1, sizeof(*ctx));
+  if (!ctx)
+    return NULL;
   ctx->users++;
   return ctx;
 }