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--></style></head><body lang=RU link=blue vlink="#954F72"><div class=WordSection1><div><p style='margin:0cm'><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'>Hello!</span></p><p class=MsoNormal><o:p> </o:p></p><p style='margin:0cm'><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'>Decrypting SRTP with Kamailio + rtpengine.</span><o:p></o:p></p><p style='margin:0cm'><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'>Hello! I have a task to decrypt SRTP for a legacy switch which doesn’t support it.</span><o:p></o:p></p><p style='margin:0cm'><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'>Simply adding rtpengine_manage("RTP/AVP") didn’t help. SDP converted from SRTP to RTP while proxying INVITE to legacy switch, but 180 Ringing wasn’t converted back to SRTP.</span><o:p></o:p></p><p style='margin:0cm'><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'>Little more detailed config snippet:</span></p><p class=MsoNormal><o:p> </o:p></p><p style='margin:0cm'><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'>route[RELAY] {</span><o:p></o:p></p><p style='margin:0cm'><span class=apple-tab-span><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'> </span></span><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'>...</span><o:p></o:p></p><p style='margin:0cm'><span class=apple-tab-span><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'> </span></span><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'>if (is_method("INVITE")) {</span></p><p class=MsoNormal><o:p> </o:p></p><p style='margin:0cm'><span class=apple-tab-span><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'> </span></span><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'>if ($rd=~$var(switch_ip_mask)) {</span><o:p></o:p></p><p style='margin:0cm'><span class=apple-tab-span><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'> </span></span><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'>rtpengine_manage("RTP/AVP");</span><o:p></o:p></p><p style='margin:0cm'><span class=apple-tab-span><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'> </span></span><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'>} else {</span><o:p></o:p></p><p style='margin:0cm'><span class=apple-tab-span><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'> </span></span><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'>rtpengine_manage();</span><o:p></o:p></p><p style='margin:0cm'><span class=apple-tab-span><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'> </span></span><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'>}</span><o:p></o:p></p><p style='margin:0cm'><span class=apple-tab-span><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'> </span></span><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'>...</span><o:p></o:p></p><p style='margin:0cm'><span class=apple-tab-span><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'> </span></span><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'>}</span></p><p class=MsoNormal><o:p> </o:p></p><p style='margin:0cm'><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'>Could someone please advise typical scenarios to achieve it, I suppose the task is pretty standard.</span></p><p class=MsoNormal><o:p> </o:p></p><p style='margin:0cm'><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222;background:white'>Thank you in advance!</span></p></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>