[OpenSIPS-Users] Preventing invalid packet parsing

[Alex Balashov]

On 06/28/2016 11:06 AM, Owais Ahmad wrote:

> Thats not the case Alex. But I am expecting a large number of UDP
> messages arriving on the same port as my udp listening socket.
> Just want to be sure there is no wasteful work done parsing such packets.

You can be reasonably sure that OpenSIPS "fingerprints" such packets 
quite efficiently and, if it doesn't type as a SIP packet, it won't be 
parsed.

For more details, see:

https://github.com/OpenSIPS/opensips/blob/master/parser/msg_parser.c#L543

As you can see, it parses the first line of the message first, and 
doesn't do any unnecessary work to parse the whole message if the first 
line doesn't suggest it's SIP.

I wouldn't worry about this "premature optimisation". :-)

-- 
Alex Balashov | Principal | Evariste Systems LLC
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