From 5f443298fea58d047f7f7b32e5bccad259e364b9 Mon Sep 17 00:00:00 2001 From: Neels Hofmeyr Date: Fri, 21 Oct 2016 01:35:57 +0200 Subject: mgcp: hack RAB success from nano3G: patch first RTP payload The ip.access nano3G needs the first RTP payload's first two bytes to read hex 'e400', or it will reject the RAB assignment. Add flag patched_first_rtp_payload to mgcp_rtp_state to detect the first RTP payload on a stream, and overwrite its first bytes with e400. This should probably be configurable, but seems to not harm other femto cells (as long as we patch only the first RTP payload in each stream). Only do this when sending to the BTS side. Change-Id: If0887b0b7714fc204f2addab2d43d44bb283ba21 --- openbsc/src/libmgcp/mgcp_network.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'openbsc/src') diff --git a/openbsc/src/libmgcp/mgcp_network.c b/openbsc/src/libmgcp/mgcp_network.c index 5686e5944..b64e25dd7 100644 --- a/openbsc/src/libmgcp/mgcp_network.c +++ b/openbsc/src/libmgcp/mgcp_network.c @@ -666,6 +666,14 @@ int mgcp_send(struct mgcp_endpoint *endp, int dest, int is_rtp, ); forward_data(rtp_end->rtp.fd, &endp->taps[tap_idx], buf, len); + + if (tap_idx == MGCP_TAP_BTS_OUT + && !rtp_state->patched_first_rtp_payload) { + uint8_t *data = &buf[12]; + osmo_hexparse("e400", data, 2); + rtp_state->patched_first_rtp_payload = true; + } + rc = mgcp_udp_send(rtp_end->rtp.fd, &rtp_end->addr, rtp_end->rtp_port, buf, len); @@ -685,6 +693,7 @@ int mgcp_send(struct mgcp_endpoint *endp, int dest, int is_rtp, ntohs(rtp_end->rtp_port), ntohs(rtp_end->rtcp_port) ); + return mgcp_udp_send(rtp_end->rtcp.fd, &rtp_end->addr, rtp_end->rtcp_port, buf, rc); -- cgit v1.2.3