Denys
ok for 1) and 2) but for regression testing I would like you to provide me a 
pcap file I can use for testing future changes.

You can either provide me the patch or I can provide you SVN write access.

Thanks Luca

On 07 Nov 2013, at 07:07, Denys Fedoryshchenko <[email protected]> 
wrote:

> Hi
> 
> Not sure if it is correct maillist.
> After debugging problem of whatsapp detection (it is now over port 5222 and 
> using TLS handshake), i noticed that program doesn't catch server side 
> certificates at all on openssl s_client simulation, and also doesn't detect 
> whatsapp at all too.
> 
> What i found:
> As i remember we can find certificate or name of server over two ways:
> 1) SNI (optional)
> 2) Server certificate
> 
> For now i concentrated on server certificate:
> 1)We check total_len specified in TLS packet, if it is more than total packet 
> length we intercepted. If it is more than packet - we just don't check 
> anything.
>    if (total_len > packet->payload_packet_len)
>        total_len = packet->payload_packet_len;
> 
>    if(total_len <= packet->payload_packet_len) {
> 
> On my opinion it is wrong, we can truncate total_len, and check "what is 
> available", and it is very common case, certificate often doesn't fit in one 
> packet, but name most probably will be seen, so i add before that lines (and 
> condition can be removed maybe).
>   /* Truncate total len, search at least in incomplete packet */
>    if (total_len > packet->payload_packet_len)
> <------>total_len = packet->payload_packet_len;
> 
> 
> 2)      if(handshake_protocol == 0x02 /* Server Hello */) {
> handshake_protocol probably misleading, at this offset (0x5) usually located 
> "message type", which is for certificate 11 (0xb). So i added "|| 
> handshake_protocol == 0xb" in condition
> 
> After that it successfully detected server certificate of whatsapp.
> 
> Should i supply it as a patch, if this way is ok?
> 
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