From be097ca15534d3f197c2068cd302fd8d90c459a1 Mon Sep 17 00:00:00 2001 From: Andreas Eversberg Date: Thu, 14 Mar 2013 09:41:18 +0100 Subject: Drop bad speech frames rather than forwarding them via RTP Some RTP endpoints may not check for bad frame indications, so a frame that is marked as bad may be still forwarded, which creates anoying noise. This patch drops these frames. It depends on the other RTP endpoint how dropped frames are handled. (insert silence, extrapolate speech...) --- openbsc/src/libtrau/rtp_proxy.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'openbsc/src/libtrau/rtp_proxy.c') diff --git a/openbsc/src/libtrau/rtp_proxy.c b/openbsc/src/libtrau/rtp_proxy.c index 52abad0ce..0aa325d24 100644 --- a/openbsc/src/libtrau/rtp_proxy.c +++ b/openbsc/src/libtrau/rtp_proxy.c @@ -327,27 +327,36 @@ int rtp_send_frame(struct rtp_socket *rs, struct gsm_data_frame *frame) switch (frame->msg_type) { case GSM_TCHF_FRAME: + if ((frame->data[0] >> 4) != 0xd) + goto bfi; payload_type = RTP_PT_GSM_FULL; payload_len = RTP_LEN_GSM_FULL; duration = RTP_GSM_DURATION; break; case GSM_TCHF_FRAME_EFR: + if ((frame->data[0] >> 4) != 0xc) + goto bfi; payload_type = (dynamic_pt) ? : RTP_PT_GSM_EFR; payload_len = RTP_LEN_GSM_EFR; duration = RTP_GSM_DURATION; break; case GSM_TCHH_FRAME: + if ((frame->data[0] & 0xf0) != 0x00) + goto bfi; payload_type = (dynamic_pt) ? : RTP_PT_GSM_HALF; payload_len = RTP_LEN_GSM_HALF; duration = RTP_GSM_DURATION; break; case GSM_TCH_FRAME_AMR: + if ((frame->data[2] & 0x04) != 0x04) + goto bfi; payload_type = (dynamic_pt) ? : RTP_PT_AMR; payload_len = frame->data[0]; duration = RTP_GSM_DURATION; is_amr = 1; break; case GSM_BAD_FRAME: +bfi: payload_type = 0; payload_len = 0; duration = RTP_GSM_DURATION; -- cgit v1.2.3