I am facing an issue in understanding how the min_se should be working in kamailio. As per the SST documentation, it seems like if the min_se is configured as 500, then any value of Session-Expires OR MIN-SE if lower than 500, can be responded to by a 422.

However, I strangely see the reverse happening. To investigate further, I looked in to the ki_sst_check_min() code in the master, and these seems like a potential issue.

Ref Code: Inside ki_sst_check_min(), there is an if condition like below:

if (sst_min_se < MIN(minse, se.interval)) { 

However, shouldn't it be the other way around? ie 

if (sst_min_se > MIN(minse, se.interval)) { 

because we need to send 422 if the received value(in INVITE etc) is smaller than the sst configure min_se value? 

I also found a different documentation, at https://git.sgu.ru/oldssu/ex-opensips/blob/cb9df8d59dbb254a9d862569fd5d11f6656c597d/modules/sst/sst_handlers.c where the check is as below?

if (sst_min_se > MIN(minse, se.interval)) { 

Can someone confirm if this is broken, or my understanding is incorrect?

Regards,

Harneet 

 
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