mgcp: Separate recv from net/bts and remove autodetection
This allows a more strict check on the source of RTP messages
and we can more easily reject those. For the BTS without an ip
address we will also update the ip address.
diff --git a/openbsc/src/mgcp/mgcp_network.c b/openbsc/src/mgcp/mgcp_network.c
index 107d2fd..729a89c 100644
--- a/openbsc/src/mgcp/mgcp_network.c
+++ b/openbsc/src/mgcp/mgcp_network.c
@@ -211,13 +211,54 @@
return rc;
}
-static int rtp_data_cb(struct bsc_fd *fd, unsigned int what)
+static int rtp_data_net(struct bsc_fd *fd, unsigned int what)
+{
+ char buf[4096];
+ struct sockaddr_in addr;
+ struct mgcp_endpoint *endp;
+ int rc, proto;
+
+ endp = (struct mgcp_endpoint *) fd->data;
+
+ rc = recevice_from(endp, fd->fd, &addr, buf, sizeof(buf));
+ if (rc <= 0)
+ return -1;
+
+ if (memcmp(&addr.sin_addr, &endp->net_end.addr, sizeof(addr.sin_addr)) != 0) {
+ LOGP(DMGCP, LOGL_ERROR,
+ "Data from wrong address %s on 0x%x\n",
+ inet_ntoa(addr.sin_addr), ENDPOINT_NUMBER(endp));
+ return -1;
+ }
+
+ if (endp->net_end.rtp_port != addr.sin_port &&
+ endp->net_end.rtcp_port != addr.sin_port) {
+ LOGP(DMGCP, LOGL_ERROR,
+ "Data from wrong source port %d on 0x%x\n",
+ ntohs(addr.sin_port), ENDPOINT_NUMBER(endp));
+ return -1;
+ }
+
+ /* throw away the dummy message */
+ if (rc == 1 && buf[0] == DUMMY_LOAD) {
+ LOGP(DMGCP, LOGL_NOTICE, "Filtered dummy from network on 0x%x\n",
+ ENDPOINT_NUMBER(endp));
+ return 0;
+ }
+
+ proto = fd == &endp->net_end.rtp ? PROTO_RTP : PROTO_RTCP;
+ endp->net_end.packets += 1;
+ return send_to(endp, DEST_BTS, proto == PROTO_RTP, &addr, &buf[0], rc);
+}
+
+
+static int rtp_data_bts(struct bsc_fd *fd, unsigned int what)
{
char buf[4096];
struct sockaddr_in addr;
struct mgcp_endpoint *endp;
struct mgcp_config *cfg;
- int rc, dest, proto;
+ int rc, proto;
endp = (struct mgcp_endpoint *) fd->data;
cfg = endp->cfg;
@@ -226,53 +267,35 @@
if (rc <= 0)
return -1;
-
- /*
- * Figure out where to forward it to. This code assumes that we
- * have received the Connection Modify and know who is a legitimate
- * partner. According to the spec we could attempt to forward even
- * after the Create Connection but we will not as we are not really
- * able to tell if this is legitimate.
- */
- dest = memcmp(&addr.sin_addr, &endp->net_end.addr, sizeof(addr.sin_addr)) == 0 &&
- (endp->net_end.rtp_port == addr.sin_port || endp->net_end.rtcp_port == addr.sin_port)
- ? DEST_BTS : DEST_NETWORK;
- proto = (fd == &endp->net_end.rtp || fd == &endp->bts_end.rtp) ? PROTO_RTP : PROTO_RTCP;
+ proto = &endp->bts_end.rtp ? PROTO_RTP : PROTO_RTCP;
/* We have no idea who called us, maybe it is the BTS. */
- if (dest == DEST_NETWORK && endp->bts_end.rtp_port == 0) {
- /* it was the BTS... */
- if (!cfg->bts_ip
- || memcmp(&addr.sin_addr, &cfg->bts_in, sizeof(cfg->bts_in)) == 0
- || memcmp(&addr.sin_addr, &endp->bts_end.addr, sizeof(endp->bts_end.addr)) == 0) {
- if (proto == PROTO_RTP) {
- endp->bts_end.rtp_port = addr.sin_port;
- } else {
- endp->bts_end.rtcp_port = addr.sin_port;
- }
+ /* it was the BTS... */
+ if (!cfg->bts_ip
+ || memcmp(&addr.sin_addr, &cfg->bts_in, sizeof(cfg->bts_in)) == 0
+ || memcmp(&addr.sin_addr, &endp->bts_end.addr, sizeof(endp->bts_end.addr)) == 0) {
+ if (proto == PROTO_RTP)
+ endp->bts_end.rtp_port = addr.sin_port;
+ else
+ endp->bts_end.rtcp_port = addr.sin_port;
- endp->bts_end.addr = addr.sin_addr;
- LOGP(DMGCP, LOGL_NOTICE, "Found BTS for endpoint: 0x%x on port: %d/%d of %s\n",
- ENDPOINT_NUMBER(endp), ntohs(endp->bts_end.rtp_port), ntohs(endp->bts_end.rtcp_port),
- inet_ntoa(addr.sin_addr));
-
- }
+ endp->bts_end.addr = addr.sin_addr;
+ LOGP(DMGCP, LOGL_NOTICE, "Found BTS for endpoint: 0x%x on port: %d/%d of %s\n",
+ ENDPOINT_NUMBER(endp), ntohs(endp->bts_end.rtp_port), ntohs(endp->bts_end.rtcp_port),
+ inet_ntoa(addr.sin_addr));
}
/* throw away the dummy message */
if (rc == 1 && buf[0] == DUMMY_LOAD) {
- LOGP(DMGCP, LOGL_NOTICE, "Filtered dummy on 0x%x\n",
+ LOGP(DMGCP, LOGL_NOTICE, "Filtered dummy from bts on 0x%x\n",
ENDPOINT_NUMBER(endp));
return 0;
}
/* do this before the loop handling */
- if (dest == DEST_NETWORK)
- ++endp->bts_end.packets;
- else
- ++endp->net_end.packets;
+ endp->bts_end.packets += 1;
- return send_to(endp, dest, proto == PROTO_RTP, &addr, &buf[0], rc);
+ return send_to(endp, DEST_NETWORK, proto == PROTO_RTP, &addr, &buf[0], rc);
}
static int create_bind(const char *source_addr, struct bsc_fd *fd, int port)
@@ -355,19 +378,19 @@
int mgcp_bind_bts_rtp_port(struct mgcp_endpoint *endp, int rtp_port)
{
endp->bts_end.local_port = rtp_port;
- endp->bts_end.rtp.cb = rtp_data_cb;
+ endp->bts_end.rtp.cb = rtp_data_bts;
endp->bts_end.rtp.data = endp;
endp->bts_end.rtcp.data = endp;
- endp->bts_end.rtcp.cb = rtp_data_cb;
+ endp->bts_end.rtcp.cb = rtp_data_bts;
return bind_rtp(endp->cfg, &endp->bts_end, ENDPOINT_NUMBER(endp));
}
int mgcp_bind_net_rtp_port(struct mgcp_endpoint *endp, int rtp_port)
{
endp->net_end.local_port = rtp_port;
- endp->net_end.rtp.cb = rtp_data_cb;
+ endp->net_end.rtp.cb = rtp_data_net;
endp->net_end.rtp.data = endp;
endp->net_end.rtcp.data = endp;
- endp->net_end.rtcp.cb = rtp_data_cb;
+ endp->net_end.rtcp.cb = rtp_data_net;
return bind_rtp(endp->cfg, &endp->net_end, ENDPOINT_NUMBER(endp));
}