Integrated support of WSS transport using libwebsocket

.gitignore

@@ -54,3 +54,8 @@ cmake_install.cmake
 # Ignore autogenerated version.h.
 /include/version.cmake
 /version.h
+
+# Ignore VSCore related stuff
+build/
+settings.json
+*.code-workspace

CHANGES.md

@@ -1,3 +1,10 @@
+Feature added in 3.7.x
+======================
+- Enabled support of RFC 7118 The WebSocket Protocol as a Transport for the Session Initiation Protocol (SIP)
+- Based on libwebsocket and only in client mode and WSS only.
+- added a -w1 option to specify SIP transport
+- added a USE_WSS definition in CMakeList.txt to enable it
+
 Features added in 3.7.5
 =======================
 

CMakeLists.txt

@@ -111,6 +111,10 @@ function(apply_common_sipp_dependencies TARGET_NAME)
   if(BUILD_STATIC AND MSYS)
     target_link_libraries(${TARGET_NAME} crypt32)
   endif()
+
+  if(USE_WSS)
+    target_link_libraries(${TARGET_NAME} ${LIBWEBSOCKETS_LIBRARIES})
+  endif()
 endfunction()
 
 optional_library(SCTP "Build with SCTP support")
@@ -293,6 +297,17 @@ if(USE_SCTP)
   find_library(SCTP_LIBRARY sctp)
 endif()
 
+# Option principale
+option(USE_WSS "Enable WebSocket Secure (WSS) support via libwebsockets" OFF)
+
+if(USE_WSS)
+    find_package(PkgConfig REQUIRED)
+    pkg_check_modules(LIBWEBSOCKETS REQUIRED libwebsockets)
+    add_definitions("-DUSE_WSS")
+    set(LIBWEBSOCKETS_LIBRARIES ${LIBWEBSOCKETS_LIBRARIES})
+    message(STATUS "Found libwebsockets: ${LIBWEBSOCKETS_LIBRARIES}")
+
+endif()
 # add the main executable
 add_sipp_target(sipp
   SOURCES "${PROJECT_SOURCE_DIR}/src/sipp.cpp"

README.md

@@ -35,7 +35,9 @@ This is the SIPp package. Please refer to the
 Normally, you should be able to build SIPp by using CMake:
 
 ```
-cmake .
+mkdir build
+cd build
+cmake ..
 make
 ```
 
@@ -59,6 +61,26 @@ The TLS key log file format is described here: https://datatracker.ietf.org/doc/
 
 _Please note the security considerations ("3. Security Considerations")!_
 
+To enable SIP over WebSocket feature pass `-DUSE_WSS=ON` to cmake. You need to have compiled [libwebsocket](https://libwebsockets.org/) before.
+And on order to avoid dynamic dependency, use only the static version. Here are simple instructions to build the lib on for linux:
+
+```
+cd libwebsocket
+mkdir build
+cd build
+cmake  -DCMAKE_INSTALL_PREFIX=/usr -DLWS_WITHOUT_TESTAPPS=ON -DLWS_WITH_SSL=ON -DLWS_WITH_SHARED=OFF -DLWS_WITH_STATIC=OFF ..
+make
+sudo make install
+```
+Then compile sipp with -DUSE_WSS=1 
+```
+cd sipp
+mkdir build
+cd build
+cmake .. -DUSE_WSS=1
+make
+```
+
 ## Static builds
 
 SIPp can be built into a single static binary, removing the need for

docs/installation.rst

@@ -66,6 +66,7 @@ Installing SIPp
     + For TLS support: OpenSSL >= 1.1.0 or WolfSSL >= 3.15.0
     + For pcap play support: libpcap and libnet
     + For SCTP support: lksctp-tools
+    + For WSS support: libwebsocket
     + For distributed pauses: `Gnu Scientific Libraries`_
 
 + You have four options to compile SIPp:

docs/transport.rst

@@ -158,6 +158,12 @@ This mode is generally used for emulating user agents calling a SIP
 server.
 
 
+WSS mode
+````````
+sipp supports SIP over secure WebSocket in mono socket mode (-t w1).
+Only client mode is supported for now. It is generally used to emulate
+WebRTC clients.
+
 IPv6 support
 ````````````
 

include/sipp.hpp

@@ -105,6 +105,7 @@
 #define T_TCP                      1
 #define T_TLS                      2
 #define T_SCTP                     3
+#define T_WSS                      4
 
 #ifdef USE_TLS
 #define DEFAULT_TLS_CERT           "cacert.pem"
@@ -113,7 +114,18 @@
 #define DEFAULT_TLS_CRL            ""
 #endif
 
-#define TRANSPORT_TO_STRING(p)     ((p==T_TCP) ? "TCP" : ((p==T_TLS)? "TLS" : ((p==T_UDP)? "UDP" : "SCTP")))
+inline const char * TRANSPORT_TO_STRING(int p) {
+    switch(p)
+    {
+        case T_TCP: return "TCP";
+        case T_UDP: return "UDP";
+        case T_TLS: return "TLS";
+        case T_SCTP: return "SCTP";
+        case T_WSS: return "WSS";
+        default: break;
+    }
+    return "Unknown";
+}
 
 #define SIPP_MAXFDS                65536
 

include/socket.hpp

@@ -30,6 +30,10 @@
 #define SCTP_UP 2
 #endif
 
+#ifdef USE_WSS
+#include "libwebsockets.h"
+#endif
+
 /**
  * On some systems you must pass the exact sockaddr struct size to
  * connect/bind/sendto calls. Passing a length that is too large
@@ -99,6 +103,10 @@ class SIPpSocket {
     int bind_to_device(const char* device_name);
 #endif
 
+#ifdef USE_WSS
+    void lws_callback_wss(enum lws_callback_reasons reason, void *in, size_t len);
+#endif
+
     static void pollset_process(int wait);
 
     int ss_count = 1;           /* How many users are there of this socket? */
@@ -150,6 +158,17 @@ class SIPpSocket {
 #ifdef USE_SCTP
     int sctpstate = SCTP_DOWN;
 #endif
+
+#ifdef USE_WSS
+    void init_lws_context();
+    void close_wss();
+    void wss_event_loop(int revents);
+    int wss_send(const void * buf, int len);
+
+    struct lws *wsi;                  // Connexion WebSocket
+    bool wss_connected;
+    struct socketbuf * wss_out;
+#endif
 };
 
 

src/call.cpp

@@ -1361,11 +1361,11 @@ bool call::connect_socket_if_needed()
         if (sipp_bind_socket(call_socket, &saddr, &call_port)) {
             ERROR_NO("Unable to bind UDP socket");
         }
-    } else { /* TCP, SCTP or TLS. */
+    } else { /* TCP, SCTP, WSS or TLS. */
         struct sockaddr_storage *L_dest = &remote_sockaddr;
 
         if ((associate_socket(SIPpSocket::new_sipp_call_socket(use_ipv6, transport, &existing))) == nullptr) {
-            ERROR_NO("Unable to get a TCP/SCTP/TLS socket");
+            ERROR_NO("Unable to get a TCP/SCTP/TLS/WSS socket");
         }
         call_socket->ss_count++;
 
@@ -5775,18 +5775,29 @@ call::T_ActionResult call::executeAction(const char* msg, message* curmsg)
                 protocol = T_TLS;
             } else if (!strcmp(str_protocol, "sctp") || !strcmp(str_protocol, "SCTP")) {
                 protocol = T_SCTP;
-            } else {
+            } else if (!strcmp(str_protocol, "wss") || !strcmp(str_protocol, "WSS")) {
+                protocol = T_WSS;
+            }
+            else {
                 ERROR("Unknown transport for setdest: '%s'", str_protocol);
             }
 
             if (!call_socket && ((protocol == T_TCP && transport == T_TCP) ||
-                                 (protocol == T_SCTP && transport == T_SCTP))) {
+                                 (protocol == T_SCTP && transport == T_SCTP) ||
+                                 (protocol == T_WSS && transport == T_WSS))) {
                 bool existing;
+                LOG_MSG("Creating new call socket");
                 if ((associate_socket(SIPpSocket::new_sipp_call_socket(use_ipv6, transport, &existing))) == nullptr) {
-                    switch (protocol) {
+                    switch (protocol)
+                    {
+                    case T_WSS:
+                        ERROR_NO("Unable to get a WSS socket");
+                        break;
+
                     case T_SCTP:
                         ERROR_NO("Unable to get a SCTP socket");
                         break;
+
                     default:
                         ERROR_NO("Unable to get a TCP socket");
                     }
@@ -5816,6 +5827,8 @@ call::T_ActionResult call::executeAction(const char* msg, message* curmsg)
                 if (call_socket->ss_count > 1) {
                     ERROR("Can not change destinations for a TCP/SCTP socket that has more than one user.");
                 }
+            } else if (protocol == T_WSS) {
+                ERROR("Changing destinations is not supported for WSS.");
             }
 
             if (gai_getsockaddr(&call_peer, str_host, port,

src/call_generation_task.cpp

@@ -165,6 +165,7 @@ bool CallGenerationTask::run()
             case T_TCP:
             case T_SCTP:
             case T_TLS:
+            case T_WSS:
                 call_ptr->associate_socket(tcp_multiplex);
                 tcp_multiplex->ss_count++;
                 break;

src/sipp.cpp

@@ -174,6 +174,9 @@ struct sipp_option options_table[] = {
 #endif
         "- c1: u1 + compression (only if compression plugin loaded),\n"
         "- cn: un + compression (only if compression plugin loaded).  This plugin is not provided with SIPp.\n"
+#ifdef USE_WSS
+        "- w1: Secure Web Socket with one socket,\n"
+#endif
         , SIPP_OPTION_TRANSPORT, nullptr, 1
     },
     {"i", "Set the local IP address for 'Contact:','Via:', and 'From:' headers. Default is primary host IP address.\n", SIPP_OPTION_IP, local_ip, 1},
@@ -1643,6 +1646,11 @@ int main(int argc, char *argv[])
                     ERROR("To use TLS transport you must compile SIPp with OpenSSL or WolfSSL");
 #endif
                     break;
+
+                case 'w':
+                    transport = T_WSS;
+                    break;
+
                 case 'c':
                     if (strlen(comp_error)) {
                         ERROR("No " COMP_PLUGIN " plugin available: %s", comp_error);