[asterisk-users] SRTP unprotect failed ...

[hw]

On Thursday, January 16, 2020 4:44:23 PM CET Joshua C. Colp wrote:
> On Thu, Jan 16, 2020 at 11:35 AM hw <hw at gc-24.de> wrote:
> > On Tuesday, January 14, 2020 5:29:04 PM CET hw wrote:
> > > Hi,
> > > 
> > > I'm getting messages like
> > > 
> > > 
> > > res_srtp.c:395 ast_srtp_unprotect: SRTP unprotect failed with replay
> > 
> > check
> > 
> > > failed (index too old), retrying == SRTP unprotect failed on SSRC
> > 
> > 576693764
> > 
> > > because of authentication failure 10 == SRTP unprotect failed on SSRC
> > > 576693764 because of authentication failure 160 [...]
> > > 
> > > 
> > > ... after a couple minutes during voice calls after which the connection
> > 
> > is
> > 
> > > being aborted.  It seems that not all connections are affected but only
> > > a
> > > few, though that would need further verification.
> > > 
> > > Is this a bug, or due to a bad internet connection (maybe packet loss?)?
> > > Can I do something to look into this?
> > > 
> > > asterisk -V
> > > Asterisk 16.4.0
> > 
> > I've upgraded asterisk to version 17 from git, and the problem remains.
> 
> What is the remote endpoint?

That's the VOIP provider.  I've contacted their support and am still waiting 
for an answer.

> The message itself is occurring because we are receiving encrypted traffic
> and failing to decrypt. I've seen this in recent times but it's been
> because of the remote endpoint and not Asterisk itself. Since it's
> encrypted and visibility into things isn't great, it's hard to point to
> precisely what is going on though.

Thanks, that's what I've been thinking after all the testing and after seeing 
a comment to that end in the source.  Perhaps encryption is finally becoming 
more widespread and brings about issues which haven't been noticeable before.