[OpenSIPS-Users] bad message

[Alex Balashov]

Hello,

It's not clear that OpenSIPS really requires 'protection' from malformed SIP messages. They don't do any obvious harm.

More generally, there's no way to use the parser to validate SIP messages for morphological correctness without... using the parser to validate them. How would you know if they're bad messages "a priori"?

If your goal is to block source IPs which generate a large amount of these invalid messages, that's another matter. A log analysis-triggered automatic firewalling tool such as Fail2ban[1], perhaps in concert with a system like APIBAN, might be your best bet.

-- Alex

[1] https://github.com/fail2ban/fail2ban

> On Dec 8, 2024, at 1:06 pm, APach via Users <users at lists.opensips.org> wrote:
> 
> Dear Team.
> 
> How to protect the server from messages like this & how to block them?
> 
> 
> Dec  8 19:45:40 mx [1279]: INFO:core:parse_first_line: method not followed by SP
> Dec  8 19:45:40 mx [1279]: INFO:core:parse_first_line: bad message
> Dec  8 19:45:40 mx [1279]: ERROR:core:parse_msg: message=<S.#002O#033`\G#031W#003RYRSZTT#014-#020C3#017\#013k\G-X#032SZin:E6T#0349&u#013yO`M[#015^#036 at mzKXW#022#005/,Y#011#025GD[}#007">
> Dec  8 19:45:40 mx /usr/sbin/opensips[1279]: ERROR:core:receive_msg: Unable to parse msg received from [147.45.78.98:11072]
> 
> 
> 
> 
> _______________________________
> Best Regards Andriy Pachkovskyy
> Mob. tel. +48504122924
> Mob. tel. +380679421834
> Sip tel.   220000 at lviv-ua.com
> Email:    apach at lviv-ua.com
> Jabber:  apach at lviv-ua.com
> <ps-error2024-12-08 19-57-31.png>_______________________________________________
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-- 
Alex Balashov
Principal Consultant
Evariste Systems LLC
Web: https://evaristesys.com
Tel: +1-706-510-6800