How to create an universal RTSP/RTMP ondemand proxy?

[rafox2005]

Question

MediaMTX Version: v1.5.1
Command: docker run --rm -it -e MTX_PROTOCOLS=tcp -e MTX_WEBRTCADDITIONALHOSTS=azkaban -p 8554:8554 -p 1935:1935 -p 8888:8888 -p 8889:8889 -p 8890:8890/udp -p 8189:8189/udp --volume ${PWD}/mediamtx.yml:/mediamtx.yml bluenviron/mediamtx:latest-ffmpeg

Hi, I want to use MediaMTX as a RTSP proxy passthrough for universal RTSP streams.

Ex: When I connect to rtsp://mediamtx:8554/proxy_rtsp://admin:password@external_ip:554/cam/realmonitor?channel=03&subtype=0 it streams the RTSP at rtsp://admin:password@external_ip:554/cam/realmonitor?channel=03&subtype=0

I tried a few things:

1. Using the example regex to proxy

paths:
  "~^proxy_(.+)$":
    # If path name is a regular expression, $G1, G2, etc will be replaced
    # with regular expression groups.
    source: $G1
    sourceOnDemand: yes

Error:
ERR: invalid source: '$G1' and crashes

2. Using a groupable RTSP stream regex

paths:
  # example:
  # my_camera:
  #   source: rtsp://my_camera

  # Settings under path "all_others" are applied to all paths that
  # do not match another entry.
  "~(https?|rtsp|qvmc|rtmp):\\/\\/(?:([^\\s@\\/]+?)[@])?([^\\s\\/:]+)(?:[:]([0-9]+))?(?:(\\/[^\\s?#]+)([?][^\\s#]+)?)?([#]\\S*)?":
    # If path name is a regular expression, $G1, G2, etc will be replaced
    # with regular expression groups.
    source: rtsp://$G2@$G3/:$G4$G5$G6
    sourceOnDemand: yes

Connect RTSP Stream:
rtsp://azkaban:8554/rtsp:////admin:passpg609@example.sn.mynetname.net:554/cam/realmonitor?channel=03&subtype=0
Error:

(base) root@srv-noleak:/data2/libardi/mediamtx# docker run --rm -it -e MTX_PROTOCOLS=tcp -e MTX_WEBRTCADDITIONALHOSTS=azkaban -p 8554:8554 -p 1935:1935 -p 8888:8888 -p 8889:8889 -p 8890:8890/udp -p 8189:8189/udp --volume ${PWD}/mediamtx.yml:/mediamtx.yml bluenviron/mediamtx:latest-ffmpeg
2024/02/12 18:00:33 INF MediaMTX v1.5.1
2024/02/12 18:00:33 INF configuration loaded from /mediamtx.yml
2024/02/12 18:00:33 DEB path manager created
2024/02/12 18:00:33 INF [RTSP] listener opened on :8554 (TCP)
2024/02/12 18:00:33 INF [RTMP] listener opened on :1935
2024/02/12 18:00:33 INF [HLS] listener opened on :8888
2024/02/12 18:00:33 INF [WebRTC] listener opened on :8889 (HTTP), :8189 (ICE/UDP)
2024/02/12 18:00:33 INF [SRT] listener opened on :8890 (UDP)
2024/02/12 18:00:40 INF [RTSP] [conn 172.17.0.1:5578] opened
2024/02/12 18:00:40 DEB [RTSP] [conn 172.17.0.1:5578] [c->s] OPTIONS rtsp://azkaban:8554/rtsp:/admin:passpg609@example.sn.dyndns.net:554/cam/realmonitor?channel=03&subtype=0 RTSP/1.0
CSeq: 2
User-Agent: LibVLC/3.0.12 (LIVE555 Streaming Media v2016.11.28)


2024/02/12 18:00:40 DEB [RTSP] [conn 172.17.0.1:5578] [s->c] RTSP/1.0 200 OK
CSeq: 2
Public: DESCRIBE, ANNOUNCE, SETUP, PLAY, RECORD, PAUSE, GET_PARAMETER, TEARDOWN
Server: gortsplib


2024/02/12 18:00:40 DEB [RTSP] [conn 172.17.0.1:5578] [c->s] DESCRIBE rtsp://azkaban:8554/rtsp:/admin:passpg609@example.sn.dyndns.net:554/cam/realmonitor?channel=03&subtype=0 RTSP/1.0
Accept: application/sdp
CSeq: 3
User-Agent: LibVLC/3.0.12 (LIVE555 Streaming Media v2016.11.28)


2024/02/12 18:00:40 DEB [RTSP] [conn 172.17.0.1:5578] [s->c] RTSP/1.0 400 Bad Request
CSeq: 3
Server: gortsplib


2024/02/12 18:00:40 INF [RTSP] [conn 172.17.0.1:5578] closed: invalid path name: can contain only alphanumeric characters, underscore, dot, tilde, minus or slash (rtsp:/admin:passpg609@example.sn.dyndns.net:554/cam/realmonitor)
2024/02/12 18:00:44 INF [RTSP] [conn 172.17.0.1:5582] opened
2024/02/12 18:00:44 DEB [RTSP] [conn 172.17.0.1:5582] [c->s] SETUP rtsp://azkaban:8554/rtsp:/admin:passpg609@example.sn.dyndns.net:554/cam/realmonitor?channel=03&subtype=0 RTSP/1.0
CSeq: 0
Transport: RTP/AVP;unicast;client_port=9430-9431


2024/02/12 18:00:44 INF [RTSP] [session f58bb119] created by 172.17.0.1:5582
2024/02/12 18:00:44 DEB [RTSP] [conn 172.17.0.1:5582] [s->c] RTSP/1.0 461 Unsupported Transport
CSeq: 0
Server: gortsplib
Session: 5ae7a5a09b534a47b577d4ea4c7481a1


2024/02/12 18:00:44 INF [RTSP] [conn 172.17.0.1:5582] closed: invalid URL ((null))
2024/02/12 18:00:44 INF [RTSP] [session f58bb119] destroyed: not in use

PS: Current RTSP stream redacted.

The final goal is to proxy a RTSP stream while recording on the MediaMTX server.

Can someone point what I am doing wrong in this case?

Thanks!

[aler9]

Hello, the setup you are describing, which is the ability to use the server as a proxy to any URL, is seldom used since it has an intrinsic security flaw, that is the possibility for an attacker to use the server to send requests to arbitrary services or websites.

Anyway this can be accomplished if the protocol (RTSP) is fixed:

paths:
  "~^proxy_rtsp/(.+)/(.+)/(.+)/(.+)/(.+)$":
    source: rtsp://$G1:$G2@$G3:$G4/$G5
    sourceOnDemand: yes

Requests addressed to

rtsp://localhost:8554/proxy_rtsp/myuser/mypass/myhost/554/mypath

will be proxied to

rtsp://myuser:mypass@myhost:554/mypath

You can create configurations for different protocols:

paths:
  "~^proxy_rtsp/(.+)/(.+)/(.+)/(.+)/(.+)$":
    source: rtsp://$G1:$G2@$G3:$G4/$G5
    sourceOnDemand: yes

  "~^proxy_rtmp/(.+)/(.+)/(.+)/(.+)/(.+)$":
    source: rtmp://$G1:$G2@$G3:$G4/$G5
    sourceOnDemand: yes

[SMSmith]

I'm not sure this is currently working? This section of code uses the parseURL function to verify the source url is valid and that makes (at least for me) a variable port number fail the validation and fail to let mediamtx start. Am I doing something wrong?

paths:
  "~^camera/(.+)/(.+)/(.+)$":
    source: rtsp://www.validurl.com:$G1/camera/$G2/$G3
    sourceOnDemand: yes