Add support for httpd systemd socket activation

If a second socket is passed through systemd, assume it is meant for httpd use. Using it requires systemd units among the lines of: /lib/systemd/system/x11vnc.service == [Unit] Description=VNC server Requires=x11vnc.socket [Service] Type=simple ExecStart=/usr/bin/x11vnc -httpdir /usr/share/novnc -no6 -xkb -repeat -auth guess -display WAIT:0 -forever -shared == /lib/systemd/system/x11vnc.socket == [Unit] Description=VNC server socket [Socket] ListenStream=5900 ListenStream=80 [Install] WantedBy=sockets.target == systemctl enable --now x11vnc.socket Signed-off-by: Floris Bos <[email protected]>
LibVNC · Dec 12, 2021 · 1c24496 · 1c24496
1 parent 33bb72d
commit 1c24496
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Showing 2 changed files with 31 additions and 2 deletions.
diff --git a/libvncserver/httpd.c b/libvncserver/httpd.c
@@ -63,6 +63,10 @@
 #include <tcpd.h>
 #endif
 
+#ifdef LIBVNCSERVER_WITH_SYSTEMD
+#include <systemd/sd-daemon.h>
+#endif
+
 
 #define NOT_FOUND_STR "HTTP/1.0 404 Not found\r\nConnection: close\r\n\r\n" \
     "<HEAD><TITLE>File Not Found</TITLE></HEAD>\n" \
@@ -100,6 +104,32 @@ rfbHttpInitSockets(rfbScreenInfoPtr rfbScreen)
     if (!rfbScreen->httpDir)
 	return;
 
+#ifdef LIBVNCSERVER_WITH_SYSTEMD
+    if (sd_listen_fds(0) == 2) {
+        rfbSocket sock = SD_LISTEN_FDS_START + 1;
+        if (sd_is_socket(sock, AF_UNSPEC, 0, 0)) {
+            rfbErr("Systemd socket activation passed 'accept=yes' inetd style socket. Only passing listening sockets is supported for http socket\n");
+        } else if (sd_is_socket(sock, AF_UNSPEC, 0, 1)) {
+            struct sockaddr_storage sa;
+            int sa_len = sizeof(sa);
+            char hoststr[NI_MAXHOST];
+            char portstr[NI_MAXSERV];
+
+            if (getsockname(sock, (struct sockaddr *) &sa, &sa_len) == 0
+                && getnameinfo((struct sockaddr *)&sa, sa_len, hoststr, sizeof(hoststr),
+                                portstr, sizeof(portstr), NI_NUMERICHOST | NI_NUMERICSERV) == 0) {
+                rfbLog("Socket activation through systemd. Listening for HTTP connections on %s:%s\n", hoststr, portstr);
+            } else {
+                rfbLogPerror("Error retrieving nameinfo of socket received from systemd\n");
+            }
+
+            rfbScreen->httpListenSock = sock;
+        }
+
+        return;
+    }
+#endif
+
     if (rfbScreen->httpPort == 0) {
 	rfbScreen->httpPort = rfbScreen->port-100;
     }

diff --git a/libvncserver/sockets.c b/libvncserver/sockets.c
@@ -178,7 +178,7 @@ rfbInitSockets(rfbScreenInfoPtr rfbScreen)
     rfbScreen->socketState = RFB_SOCKET_READY;
 
 #ifdef LIBVNCSERVER_WITH_SYSTEMD
-    if (sd_listen_fds(0) == 1)
+    if (sd_listen_fds(0) == 1 || sd_listen_fds(0) == 2)
     {
         rfbSocket sock = SD_LISTEN_FDS_START + 0;
         if (sd_is_socket(sock, AF_UNSPEC, 0, 0))
@@ -202,7 +202,6 @@ rfbInitSockets(rfbScreenInfoPtr rfbScreen)
             rfbScreen->listenSock = sock;
             FD_SET(rfbScreen->listenSock, &(rfbScreen->allFds));
             rfbScreen->maxFd = rfbScreen->listenSock;
-            rfbProcessNewConnection(rfbScreen);
         }
         return;
     }