rtsp: Add listen mode

This makes the RTSP demuxer act as a server, listening for an
incoming connection.

Signed-off-by: Martin Storsjö <martin@martin.st>

1 files changed, 544 insertions, 29 deletions

diff --git a/libavformat/rtspdec.c b/libavformat/rtspdec.c
index 6226f41660..a3565557d4 100644
--- a/libavformat/rtspdec.c
+++ b/libavformat/rtspdec.c
@@ -22,6 +22,7 @@
 #include "libavutil/avstring.h"
 #include "libavutil/intreadwrite.h"
 #include "libavutil/mathematics.h"
+#include "libavutil/random_seed.h"
 #include "avformat.h"
 
 #include "internal.h"
@@ -31,11 +32,30 @@
 #include "rdt.h"
 #include "url.h"
 
+static const struct RTSPStatusMessage {
+    enum RTSPStatusCode code;
+    const char *message;
+} status_messages[] = {
+    { RTSP_STATUS_OK,             "OK"                               },
+    { RTSP_STATUS_METHOD,         "Method Not Allowed"               },
+    { RTSP_STATUS_BANDWIDTH,      "Not Enough Bandwidth"             },
+    { RTSP_STATUS_SESSION,        "Session Not Found"                },
+    { RTSP_STATUS_STATE,          "Method Not Valid in This State"   },
+    { RTSP_STATUS_AGGREGATE,      "Aggregate operation not allowed"  },
+    { RTSP_STATUS_ONLY_AGGREGATE, "Only aggregate operation allowed" },
+    { RTSP_STATUS_TRANSPORT,      "Unsupported transport"            },
+    { RTSP_STATUS_INTERNAL,       "Internal Server Error"            },
+    { RTSP_STATUS_SERVICE,        "Service Unavailable"              },
+    { RTSP_STATUS_VERSION,        "RTSP Version not supported"       },
+    { 0,                          "NULL"                             }
+};
+
 static int rtsp_read_close(AVFormatContext *s)
 {
     RTSPState *rt = s->priv_data;
 
-    ff_rtsp_send_cmd_async(s, "TEARDOWN", rt->control_uri, NULL);
+    if (!(rt->rtsp_flags & RTSP_FLAG_LISTEN))
+        ff_rtsp_send_cmd_async(s, "TEARDOWN", rt->control_uri, NULL);
 
     ff_rtsp_close_streams(s);
     ff_rtsp_close_connections(s);
@@ -45,6 +65,429 @@ static int rtsp_read_close(AVFormatContext *s)
     return 0;
 }
 
+static inline int read_line(AVFormatContext *s, char *rbuf, const int rbufsize,
+                            int *rbuflen)
+{
+    RTSPState *rt = s->priv_data;
+    int idx       = 0;
+    int ret       = 0;
+    *rbuflen      = 0;
+
+    do {
+        ret = ffurl_read_complete(rt->rtsp_hd, rbuf + idx, 1);
+        if (ret < 0)
+            return ret;
+        if (rbuf[idx] == '\r') {
+            /* Ignore */
+        } else if (rbuf[idx] == '\n') {
+            rbuf[idx] = '\0';
+            *rbuflen  = idx;
+            return 0;
+        } else
+            idx++;
+    } while (idx < rbufsize);
+    av_log(s, AV_LOG_ERROR, "Message too long\n");
+    return AVERROR(EIO);
+}
+
+static int rtsp_send_reply(AVFormatContext *s, enum RTSPStatusCode code,
+                           const char *extracontent, uint16_t seq)
+{
+    RTSPState *rt = s->priv_data;
+    char message[4096];
+    int index = 0;
+    while (status_messages[index].code) {
+        if (status_messages[index].code == code) {
+            snprintf(message, sizeof(message), "RTSP/1.0 %d %s\r\n",
+                     code, status_messages[index].message);
+            break;
+        }
+        index++;
+    }
+    if (!status_messages[index].code)
+        return AVERROR(EINVAL);
+    av_strlcatf(message, sizeof(message), "CSeq: %d\r\n", seq);
+    av_strlcatf(message, sizeof(message), "Server: %s\r\n", LIBAVFORMAT_IDENT);
+    if (extracontent)
+        av_strlcat(message, extracontent, sizeof(message));
+    av_strlcat(message, "\r\n", sizeof(message));
+    av_dlog(s, "Sending response:\n%s", message);
+    ffurl_write(rt->rtsp_hd, message, strlen(message));
+
+    return 0;
+}
+
+static inline int check_sessionid(AVFormatContext *s,
+                                  RTSPMessageHeader *request)
+{
+    RTSPState *rt = s->priv_data;
+    unsigned char *session_id = rt->session_id;
+    if (!session_id[0]) {
+        av_log(s, AV_LOG_WARNING, "There is no session-id at the moment\n");
+        return 0;
+    }
+    if (strcmp(session_id, request->session_id)) {
+        av_log(s, AV_LOG_ERROR, "Unexpected session-id %s\n",
+               request->session_id);
+        rtsp_send_reply(s, RTSP_STATUS_SESSION, NULL, request->seq);
+        return AVERROR_STREAM_NOT_FOUND;
+    }
+    return 0;
+}
+
+static inline int rtsp_read_request(AVFormatContext *s,
+                                    RTSPMessageHeader *request,
+                                    const char *method)
+{
+    RTSPState *rt = s->priv_data;
+    char rbuf[1024];
+    int rbuflen, ret;
+    do {
+        ret = read_line(s, rbuf, sizeof(rbuf), &rbuflen);
+        if (ret)
+            return ret;
+        if (rbuflen > 1) {
+            av_dlog(s, "Parsing[%d]: %s\n", rbuflen, rbuf);
+            ff_rtsp_parse_line(request, rbuf, rt, method);
+        }
+    } while (rbuflen > 0);
+    if (request->seq != rt->seq + 1) {
+        av_log(s, AV_LOG_ERROR, "Unexpected Sequence number %d\n",
+               request->seq);
+        return AVERROR(EINVAL);
+    }
+    if (rt->session_id[0] && strcmp(method, "OPTIONS")) {
+        ret = check_sessionid(s, request);
+        if (ret)
+            return ret;
+    }
+
+    return 0;
+}
+
+static int rtsp_read_announce(AVFormatContext *s)
+{
+    RTSPState *rt             = s->priv_data;
+    RTSPMessageHeader request = { 0 };
+    char sdp[4096];
+    int  ret;
+
+    ret = rtsp_read_request(s, &request, "ANNOUNCE");
+    if (ret)
+        return ret;
+    rt->seq++;
+    if (strcmp(request.content_type, "application/sdp")) {
+        av_log(s, AV_LOG_ERROR, "Unexpected content type %s\n",
+               request.content_type);
+        rtsp_send_reply(s, RTSP_STATUS_SERVICE, NULL, request.seq);
+        return AVERROR_OPTION_NOT_FOUND;
+    }
+    if (request.content_length && request.content_length < sizeof(sdp) - 1) {
+        /* Read SDP */
+        if (ffurl_read_complete(rt->rtsp_hd, sdp, request.content_length)
+            < request.content_length) {
+            av_log(s, AV_LOG_ERROR,
+                   "Unable to get complete SDP Description in ANNOUNCE\n");
+            rtsp_send_reply(s, RTSP_STATUS_INTERNAL, NULL, request.seq);
+            return AVERROR(EIO);
+        }
+        sdp[request.content_length] = '\0';
+        av_log(s, AV_LOG_VERBOSE, "SDP: %s\n", sdp);
+        ret = ff_sdp_parse(s, sdp);
+        if (ret)
+            return ret;
+        rtsp_send_reply(s, RTSP_STATUS_OK, NULL, request.seq);
+        return 0;
+    }
+    av_log(s, AV_LOG_ERROR,
+           "Content-Length header value exceeds sdp allocated buffer (4KB)\n");
+    rtsp_send_reply(s, RTSP_STATUS_INTERNAL,
+                    "Content-Length exceeds buffer size", request.seq);
+    return AVERROR(EIO);
+}
+
+static int rtsp_read_options(AVFormatContext *s)
+{
+    RTSPState *rt             = s->priv_data;
+    RTSPMessageHeader request = { 0 };
+    int ret                   = 0;
+
+    /* Parsing headers */
+    ret = rtsp_read_request(s, &request, "OPTIONS");
+    if (ret)
+        return ret;
+    rt->seq++;
+    /* Send Reply */
+    rtsp_send_reply(s, RTSP_STATUS_OK,
+                    "Public: ANNOUNCE, PAUSE, SETUP, TEARDOWN, RECORD\r\n",
+                    request.seq);
+    return 0;
+}
+
+static int rtsp_read_setup(AVFormatContext *s, char* host, char *controlurl)
+{
+    RTSPState *rt             = s->priv_data;
+    RTSPMessageHeader request = { 0 };
+    int ret                   = 0;
+    char url[1024];
+    RTSPStream *rtsp_st;
+    char responseheaders[1024];
+    int localport    = -1;
+    int transportidx = 0;
+    int streamid     = 0;
+
+    ret = rtsp_read_request(s, &request, "SETUP");
+    if (ret)
+        return ret;
+    rt->seq++;
+    if (!request.nb_transports) {
+        av_log(s, AV_LOG_ERROR, "No transport defined in SETUP\n");
+        return AVERROR_INVALIDDATA;
+    }
+    for (transportidx = 0; transportidx < request.nb_transports;
+         transportidx++) {
+        if (!request.transports[transportidx].mode_record ||
+            (request.transports[transportidx].lower_transport !=
+             RTSP_LOWER_TRANSPORT_UDP &&
+             request.transports[transportidx].lower_transport !=
+             RTSP_LOWER_TRANSPORT_TCP)) {
+            av_log(s, AV_LOG_ERROR, "mode=record/receive not set or transport"
+                   " protocol not supported (yet)\n");
+            return AVERROR_INVALIDDATA;
+        }
+    }
+    if (request.nb_transports > 1)
+        av_log(s, AV_LOG_WARNING, "More than one transport not supported, "
+               "using first of all\n");
+    for (streamid = 0; streamid < rt->nb_rtsp_streams; streamid++) {
+        if (!strcmp(rt->rtsp_streams[streamid]->control_url,
+                    controlurl))
+            break;
+    }
+    if (streamid == rt->nb_rtsp_streams) {
+        av_log(s, AV_LOG_ERROR, "Unable to find requested track\n");
+        return AVERROR_STREAM_NOT_FOUND;
+    }
+    rtsp_st   = rt->rtsp_streams[streamid];
+    localport = rt->rtp_port_min;
+
+    if (request.transports[0].lower_transport == RTSP_LOWER_TRANSPORT_TCP) {
+        rt->lower_transport = RTSP_LOWER_TRANSPORT_TCP;
+        if ((ret = ff_rtsp_open_transport_ctx(s, rtsp_st))) {
+            rtsp_send_reply(s, RTSP_STATUS_TRANSPORT, NULL, request.seq);
+            return ret;
+        }
+        rtsp_st->interleaved_min = request.transports[0].interleaved_min;
+        rtsp_st->interleaved_max = request.transports[0].interleaved_max;
+        snprintf(responseheaders, sizeof(responseheaders), "Transport: "
+                 "RTP/AVP/TCP;unicast;mode=receive;interleaved=%d-%d"
+                 "\r\n", request.transports[0].interleaved_min,
+                 request.transports[0].interleaved_max);
+    } else {
+        do {
+            ff_url_join(url, sizeof(url), "rtp", NULL, host, localport, NULL);
+            av_dlog(s, "Opening: %s", url);
+            ret = ffurl_open(&rtsp_st->rtp_handle, url, AVIO_FLAG_READ_WRITE,
+                             &s->interrupt_callback, NULL);
+            if (ret)
+                localport += 2;
+        } while (ret || localport > rt->rtp_port_max);
+        if (localport > rt->rtp_port_max) {
+            rtsp_send_reply(s, RTSP_STATUS_TRANSPORT, NULL, request.seq);
+            return ret;
+        }
+
+        av_dlog(s, "Listening on: %d",
+                ff_rtp_get_local_rtp_port(rtsp_st->rtp_handle));
+        if ((ret = ff_rtsp_open_transport_ctx(s, rtsp_st))) {
+            rtsp_send_reply(s, RTSP_STATUS_TRANSPORT, NULL, request.seq);
+            return ret;
+        }
+
+        localport = ff_rtp_get_local_rtp_port(rtsp_st->rtp_handle);
+        snprintf(responseheaders, sizeof(responseheaders), "Transport: "
+                 "RTP/AVP/UDP;unicast;mode=receive;source=%s;"
+                 "client_port=%d-%d;server_port=%d-%d\r\n",
+                 host, request.transports[0].client_port_min,
+                 request.transports[0].client_port_max, localport,
+                 localport + 1);
+    }
+
+    /* Establish sessionid if not previously set */
+    /* Put this in a function? */
+    /* RFC 2326: session id must be at least 8 digits */
+    while (strlen(rt->session_id) < 8)
+        av_strlcatf(rt->session_id, 512, "%u", av_get_random_seed());
+
+    av_strlcatf(responseheaders, sizeof(responseheaders), "Session: %s\r\n",
+                rt->session_id);
+    /* Send Reply */
+    rtsp_send_reply(s, RTSP_STATUS_OK, responseheaders, request.seq);
+
+    rt->state = RTSP_STATE_PAUSED;
+    return 0;
+}
+
+static int rtsp_read_record(AVFormatContext *s)
+{
+    RTSPState *rt             = s->priv_data;
+    RTSPMessageHeader request = { 0 };
+    int ret                   = 0;
+    char responseheaders[1024];
+
+    ret = rtsp_read_request(s, &request, "RECORD");
+    if (ret)
+        return ret;
+    ret = check_sessionid(s, &request);
+    if (ret)
+        return ret;
+    rt->seq++;
+    snprintf(responseheaders, sizeof(responseheaders), "Session: %s\r\n",
+             rt->session_id);
+    rtsp_send_reply(s, RTSP_STATUS_OK, responseheaders, request.seq);
+
+    rt->state = RTSP_STATE_STREAMING;
+    return 0;
+}
+
+static inline int parse_command_line(AVFormatContext *s, const char *line,
+                                     int linelen, char *uri, int urisize,
+                                     char *method, int methodsize,
+                                     enum RTSPMethod *methodcode)
+{
+    RTSPState *rt = s->priv_data;
+    const char *linept, *searchlinept;
+    linept = strchr(line, ' ');
+    if (linept - line > methodsize - 1) {
+        av_log(s, AV_LOG_ERROR, "Method string too long\n");
+        return AVERROR(EIO);
+    }
+    memcpy(method, line, linept - line);
+    method[linept - line] = '\0';
+    linept++;
+    if (!strcmp(method, "ANNOUNCE"))
+        *methodcode = ANNOUNCE;
+    else if (!strcmp(method, "OPTIONS"))
+        *methodcode = OPTIONS;
+    else if (!strcmp(method, "RECORD"))
+        *methodcode = RECORD;
+    else if (!strcmp(method, "SETUP"))
+        *methodcode = SETUP;
+    else if (!strcmp(method, "PAUSE"))
+        *methodcode = PAUSE;
+    else if (!strcmp(method, "TEARDOWN"))
+        *methodcode = TEARDOWN;
+    else
+        *methodcode = UNKNOWN;
+    /* Check method with the state  */
+    if (rt->state == RTSP_STATE_IDLE) {
+        if ((*methodcode != ANNOUNCE) && (*methodcode != OPTIONS)) {
+            av_log(s, AV_LOG_ERROR, "Unexpected command in Idle State %s\n",
+                   line);
+            return AVERROR_PROTOCOL_NOT_FOUND;
+        }
+    } else if (rt->state == RTSP_STATE_PAUSED) {
+        if ((*methodcode != OPTIONS) && (*methodcode != RECORD)
+            && (*methodcode != SETUP)) {
+            av_log(s, AV_LOG_ERROR, "Unexpected command in Paused State %s\n",
+                   line);
+            return AVERROR_PROTOCOL_NOT_FOUND;
+        }
+    } else if (rt->state == RTSP_STATE_STREAMING) {
+        if ((*methodcode != PAUSE) && (*methodcode != OPTIONS)
+            && (*methodcode != TEARDOWN)) {
+            av_log(s, AV_LOG_ERROR, "Unexpected command in Streaming State"
+                   " %s\n", line);
+            return AVERROR_PROTOCOL_NOT_FOUND;
+        }
+    } else {
+        av_log(s, AV_LOG_ERROR, "Unexpected State [%d]\n", rt->state);
+        return AVERROR_BUG;
+    }
+
+    searchlinept = strchr(linept, ' ');
+    if (searchlinept == NULL) {
+        av_log(s, AV_LOG_ERROR, "Error parsing message URI\n");
+        return AVERROR_INVALIDDATA;
+    }
+    if (searchlinept - linept > urisize - 1) {
+        av_log(s, AV_LOG_ERROR, "uri string length exceeded buffer size\n");
+        return AVERROR(EIO);
+    }
+    memcpy(uri, linept, searchlinept - linept);
+    uri[searchlinept - linept] = '\0';
+    if (strcmp(rt->control_uri, uri)) {
+        char host[128], path[512], auth[128];
+        int port;
+        char ctl_host[128], ctl_path[512], ctl_auth[128];
+        int ctl_port;
+        av_url_split(NULL, 0, auth, sizeof(auth), host, sizeof(host), &port,
+                     path, sizeof(path), uri);
+        av_url_split(NULL, 0, ctl_auth, sizeof(ctl_auth), ctl_host,
+                     sizeof(ctl_host), &ctl_port, ctl_path, sizeof(ctl_path),
+                     rt->control_uri);
+        if (strcmp(host, ctl_host))
+            av_log(s, AV_LOG_INFO, "Host %s differs from expected %s\n",
+                   host, ctl_host);
+        if (strcmp(path, ctl_path) && *methodcode != SETUP)
+            av_log(s, AV_LOG_WARNING, "WARNING: Path %s differs from expected"
+                   " %s\n", path, ctl_path);
+        if (*methodcode == ANNOUNCE) {
+            av_log(s, AV_LOG_INFO,
+                   "Updating control URI to %s\n", uri);
+            strcpy(rt->control_uri, uri);
+        }
+    }
+
+    linept = searchlinept + 1;
+    if (!av_strstart(linept, "RTSP/1.0", NULL)) {
+        av_log(s, AV_LOG_ERROR, "Error parsing protocol or version\n");
+        return AVERROR_PROTOCOL_NOT_FOUND;
+    }
+    return 0;
+}
+
+int ff_rtsp_parse_streaming_commands(AVFormatContext *s)
+{
+    RTSPState *rt = s->priv_data;
+    unsigned char rbuf[4096];
+    unsigned char method[10];
+    char uri[500];
+    int ret;
+    int rbuflen               = 0;
+    RTSPMessageHeader request = { 0 };
+    enum RTSPMethod methodcode;
+
+    ret = read_line(s, rbuf, sizeof(rbuf), &rbuflen);
+    if (ret < 0)
+        return ret;
+    ret = parse_command_line(s, rbuf, rbuflen, uri, sizeof(uri), method,
+                             sizeof(method), &methodcode);
+    if (ret) {
+        av_log(s, AV_LOG_ERROR, "RTSP: Unexpected Command\n");
+        return ret;
+    }
+
+    ret = rtsp_read_request(s, &request, method);
+    if (ret)
+        return ret;
+    rt->seq++;
+    if (methodcode == PAUSE) {
+        rt->state = RTSP_STATE_PAUSED;
+        ret       = rtsp_send_reply(s, RTSP_STATUS_OK, NULL , request.seq);
+        // TODO: Missing date header in response
+    } else if (methodcode == OPTIONS) {
+        ret = rtsp_send_reply(s, RTSP_STATUS_OK,
+                              "Public: ANNOUNCE, PAUSE, SETUP, TEARDOWN, "
+                              "RECORD\r\n", request.seq);
+    } else if (methodcode == TEARDOWN) {
+        rt->state = RTSP_STATE_IDLE;
+        ret       = rtsp_send_reply(s, RTSP_STATUS_OK, NULL , request.seq);
+        return 0;
+    }
+    return ret;
+}
+
 static int rtsp_read_play(AVFormatContext *s)
 {
     RTSPState *rt = s->priv_data;
@@ -157,6 +600,67 @@ int ff_rtsp_setup_input_streams(AVFormatContext *s, RTSPMessageHeader *reply)
     return 0;
 }
 
+static int rtsp_listen(AVFormatContext *s)
+{
+    RTSPState *rt = s->priv_data;
+    char host[128], path[512], auth[128];
+    char uri[500];
+    int port;
+    char tcpname[500];
+    unsigned char rbuf[4096];
+    unsigned char method[10];
+    int rbuflen = 0;
+    int ret;
+    enum RTSPMethod methodcode;
+
+    /* extract hostname and port */
+    av_url_split(NULL, 0, auth, sizeof(auth), host, sizeof(host), &port,
+                 path, sizeof(path), s->filename);
+
+    /* ff_url_join. No authorization by now (NULL) */
+    ff_url_join(rt->control_uri, sizeof(rt->control_uri), "rtsp", NULL, host,
+                port, "%s", path);
+    /* Create TCP connection */
+    ff_url_join(tcpname, sizeof(tcpname), "tcp", NULL, host, port,
+                "?listen&listen_timeout=%d", rt->initial_timeout * 1000);
+
+    if (ret = ffurl_open(&rt->rtsp_hd, tcpname, AVIO_FLAG_READ_WRITE,
+                         &s->interrupt_callback, NULL)) {
+        av_log(s, AV_LOG_ERROR, "Unable to open RTSP for listening\n");
+        return ret;
+    }
+    rt->state       = RTSP_STATE_IDLE;
+    rt->rtsp_hd_out = rt->rtsp_hd;
+    for (;;) { /* Wait for incoming RTSP messages */
+        ret = read_line(s, rbuf, sizeof(rbuf), &rbuflen);
+        if (ret < 0)
+            return ret;
+        ret = parse_command_line(s, rbuf, rbuflen, uri, sizeof(uri), method,
+                                 sizeof(method), &methodcode);
+        if (ret) {
+            av_log(s, AV_LOG_ERROR, "RTSP: Unexpected Command\n");
+            return ret;
+        }
+
+        if (methodcode == ANNOUNCE) {
+            ret       = rtsp_read_announce(s);
+            rt->state = RTSP_STATE_PAUSED;
+        } else if (methodcode == OPTIONS) {
+            ret = rtsp_read_options(s);
+        } else if (methodcode == RECORD) {
+            ret = rtsp_read_record(s);
+            if (!ret)
+                return 0; // We are ready for streaming
+        } else if (methodcode == SETUP)
+            ret = rtsp_read_setup(s, host, uri);
+        if (ret) {
+            ffurl_close(rt->rtsp_hd);
+            return AVERROR_INVALIDDATA;
+        }
+    }
+    return 0;
+}
+
 static int rtsp_probe(AVProbeData *p)
 {
     if (av_strstart(p->filename, "rtsp:", NULL))
@@ -169,23 +673,32 @@ static int rtsp_read_header(AVFormatContext *s)
     RTSPState *rt = s->priv_data;
     int ret;
 
-    ret = ff_rtsp_connect(s);
-    if (ret)
-        return ret;
-
-    rt->real_setup_cache = !s->nb_streams ? NULL :
-                           av_mallocz(2 * s->nb_streams * sizeof(*rt->real_setup_cache));
-    if (!rt->real_setup_cache && s->nb_streams)
-        return AVERROR(ENOMEM);
-    rt->real_setup = rt->real_setup_cache + s->nb_streams;
+    if (rt->initial_timeout > 0)
+        rt->rtsp_flags |= RTSP_FLAG_LISTEN;
 
-    if (rt->initial_pause) {
-         /* do not start immediately */
+    if (rt->rtsp_flags & RTSP_FLAG_LISTEN) {
+        ret = rtsp_listen(s);
+        if (ret)
+            return ret;
     } else {
-         if (rtsp_read_play(s) < 0) {
-            ff_rtsp_close_streams(s);
-            ff_rtsp_close_connections(s);
-            return AVERROR_INVALIDDATA;
+        ret = ff_rtsp_connect(s);
+        if (ret)
+            return ret;
+
+        rt->real_setup_cache = !s->nb_streams ? NULL :
+            av_mallocz(2 * s->nb_streams * sizeof(*rt->real_setup_cache));
+        if (!rt->real_setup_cache && s->nb_streams)
+            return AVERROR(ENOMEM);
+        rt->real_setup = rt->real_setup_cache + s->nb_streams;
+
+        if (rt->initial_pause) {
+            /* do not start immediately */
+        } else {
+            if (rtsp_read_play(s) < 0) {
+                ff_rtsp_close_streams(s);
+                ff_rtsp_close_connections(s);
+                return AVERROR_INVALIDDATA;
+            }
         }
     }
 
@@ -349,20 +862,22 @@ retry:
     }
     rt->packets++;
 
-    /* send dummy request to keep TCP connection alive */
-    if ((av_gettime() - rt->last_cmd_time) / 1000000 >= rt->timeout / 2 ||
-         rt->auth_state.stale) {
-        if (rt->server_type == RTSP_SERVER_WMS ||
-           (rt->server_type != RTSP_SERVER_REAL &&
-            rt->get_parameter_supported)) {
-            ff_rtsp_send_cmd_async(s, "GET_PARAMETER", rt->control_uri, NULL);
-        } else {
-            ff_rtsp_send_cmd_async(s, "OPTIONS", "*", NULL);
+    if (!(rt->rtsp_flags & RTSP_FLAG_LISTEN)) {
+        /* send dummy request to keep TCP connection alive */
+        if ((av_gettime() - rt->last_cmd_time) / 1000000 >= rt->timeout / 2 ||
+            rt->auth_state.stale) {
+            if (rt->server_type == RTSP_SERVER_WMS ||
+                (rt->server_type != RTSP_SERVER_REAL &&
+                 rt->get_parameter_supported)) {
+                ff_rtsp_send_cmd_async(s, "GET_PARAMETER", rt->control_uri, NULL);
+            } else {
+                ff_rtsp_send_cmd_async(s, "OPTIONS", "*", NULL);
+            }
+            /* The stale flag should be reset when creating the auth response in
+             * ff_rtsp_send_cmd_async, but reset it here just in case we never
+             * called the auth code (if we didn't have any credentials set). */
+            rt->auth_state.stale = 0;
         }
-        /* The stale flag should be reset when creating the auth response in
-         * ff_rtsp_send_cmd_async, but reset it here just in case we never
-         * called the auth code (if we didn't have any credentials set). */
-        rt->auth_state.stale = 0;
     }
 
     return 0;