RAW connector cleanup, added configfile support, added setuid support, added some more comments other places

Connector_HTTP/main.cpp

@@ -354,4 +354,5 @@ namespace Connector_HTTP{
 // Load main server setup file, default port 8080, handler is Connector_HTTP::Connector_HTTP
 #define DEFAULT_PORT 8080
 #define MAINHANDLER Connector_HTTP::Connector_HTTP
+#define CONFIGSECT HTTP
 #include "../util/server_setup.cpp"

Connector_RAW/main.cpp

@@ -1,19 +1,12 @@
 #include <iostream>
 #include "../util/ddv_socket.h"
-#include <string>
-#include <vector>
-#include <cstdlib>
-#include <cstdio>
-#include <unistd.h>
-#include <fcntl.h>
 
 int main(int argc, char  ** argv) {
   if (argc < 2){
     std::cout << "Usage: " << argv[0] << " stream_name" << std::endl;
     return 1;
   }
-  std::string input;
+  std::string input = "/tmp/shared_socket_";
-  input = "/tmp/shared_socket_";
   input += argv[1];
   DDV::Socket S(input);
   if (!S.connected()){
@@ -21,10 +14,7 @@ int main(int argc, char  ** argv) {
     return 1;
   }
   char buffer[50000];
-  int msg;
+  while(std::cout.good() && S.read(buffer,50000)){std::cout.write(buffer,50000);}
-  while(std::cout.good() && S.read(buffer,50000)){
-    std::cout.write(buffer,50000);
-  }
   S.close();
   return 0;
 }

Connector_RTMP/main.cpp

@@ -171,4 +171,5 @@ namespace Connector_RTMP{
 // Load main server setup file, default port 1935, handler is Connector_RTMP::Connector_RTMP
 #define DEFAULT_PORT 1935
 #define MAINHANDLER Connector_RTMP::Connector_RTMP
+#define CONFIGSECT RTMP
 #include "../util/server_setup.cpp"

util/ddv_socket.cpp

@@ -309,6 +309,8 @@ DDV::ServerSocket::ServerSocket(std::string address, bool nonblock){
 DDV::Socket DDV::ServerSocket::accept(bool nonblock){
   if (sock < 0){return DDV::Socket(-1);}
   int r = ::accept(sock, 0, 0);
+  //set the socket to be nonblocking, if requested.
+  //we could do this through accept4 with a flag, but that call is non-standard...
   if ((r >= 0) && nonblock){
     int flags = fcntl(r, F_GETFL, 0);
     flags |= O_NONBLOCK;

util/server_setup.cpp

@@ -1,9 +1,18 @@
 #include <signal.h>
 #include "ddv_socket.h" //DDVTech Socket wrapper
 #include "flv_tag.h" //FLV parsing with DDVTech Socket wrapper
+#include <sys/types.h>
+#include <pwd.h>
+#include <fstream>
+#define defstr(x) #x //converts a define name to string
+#define defstrh(x) "[" defstr(x) "]" //converts define name to [string]
 DDV::ServerSocket server_socket(-1);
 
-void termination_handler (int signum){
+/// Basic signal handler. Disconnects the server_socket if it receives
+/// a SIGINT, SIGHUP or SIGTERM signal, but does nothing for SIGPIPE.
+/// Disconnecting the server_socket will terminate the main listening loop
+/// and cleanly shut down the process.
+void signal_handler (int signum){
   if (!server_socket.connected()) return;
   switch (signum){
     case SIGINT: break;
@@ -12,14 +21,21 @@ void termination_handler (int signum){
     default: return; break;
   }
   server_socket.close();
-}
+}//signal_handler
 
+/// Generic main entry point and loop for DDV Connectors.
+/// This sets up the proper termination handler, checks commandline options,
+/// parses config files and opens a listening socket on the requested port.
+/// Any incoming connections will be accepted and start up the function MAINHANDLER,
+/// which should be #defined before including server_setup.cpp.
+/// The default port is set by #define DEFAULT_PORT.
+/// The configuration file section is set by #define CONFIGSECT.
 int main(int argc, char ** argv){
-  DDV::Socket CONN_fd(-1);
+  DDV::Socket S;//placeholder for incoming connections
 
   //setup signal handler
   struct sigaction new_action;
-  new_action.sa_handler = termination_handler;
+  new_action.sa_handler = signal_handler;
   sigemptyset (&new_action.sa_mask);
   new_action.sa_flags = 0;
   sigaction(SIGINT, &new_action, NULL);
@@ -27,42 +43,82 @@ int main(int argc, char ** argv){
   sigaction(SIGTERM, &new_action, NULL);
   sigaction(SIGPIPE, &new_action, NULL);
 
+  //default values
   int listen_port = DEFAULT_PORT;
   bool daemon_mode = true;
   std::string interface = "0.0.0.0";
+  std::string configfile = "/etc/ddvtech.conf";
+  std::string username = "root";
+  bool ignore_daemon = false;
+  bool ignore_interface = false;
+  bool ignore_port = false;
+  bool ignore_user = false;
   
   int opt = 0;
-  static const char *optString = "np:i:h?";
+  static const char *optString = "ndp:i:u:c:h?";
   static const struct option longOpts[] = {
     {"help",0,0,'h'},
     {"port",1,0,'p'},
     {"interface",1,0,'i'},
-    {"no-daemon",0,0,'n'}
+    {"username",1,0,'u'},
+    {"no-daemon",0,0,'n'},
+    {"daemon",0,0,'d'},
+    {"configfile",1,0,'c'}
   };
   while ((opt = getopt_long(argc, argv, optString, longOpts, 0)) != -1){
     switch (opt){
-      case 'p':
+      case 'p': listen_port = atoi(optarg); ignore_port = true; break;
-        listen_port = atoi(optarg);
+      case 'i': interface = optarg; ignore_interface = true; break;
-        break;
+      case 'n': daemon_mode = false; ignore_daemon = true; break;
-      case 'i':
+      case 'd': daemon_mode = true; ignore_daemon = true; break;
-        interface = optarg;
+      case 'c': configfile = optarg; break;
-        break;
+      case 'u': username = optarg; ignore_user = true; break;
-      case 'n':
-        daemon_mode = false;
-        break;
       case 'h':
       case '?':
-        printf("Options: -h[elp], -?, -n[o-daemon], -p[ort] #\n");
+        printf("Options: -h[elp], -?, -n[odaemon], -d[aemon], -p[ort] VAL, -i[nterface] VAL, -c[onfigfile] VAL, -u[sername] VAL\n");
+        printf("Defaults:\n  interface: 0.0.0.0\n  port: %i\n  daemon mode: true\n  configfile: /etc/ddvtech.conf\n  username: root\n", listen_port);
+        printf("Username root means no change to UID, no matter what the UID is.\n");
+        printf("If the configfile exists, it is always loaded first. Commandline settings then overwrite the config file.\n");
+        printf("\nThis process takes it directives from the %s section of the configfile.\n", defstrh(CONFIGSECT));
         return 1;
         break;
     }
-  }
+  }//commandline options parser
 
+  std::ifstream conf(configfile.c_str(), std::ifstream::in);
+  std::string tmpstr;
+  bool acc_comm = false;
+  size_t foundeq;
+  if (conf.fail()){
+    #if DEBUG >= 3
+    fprintf(stderr, "Configuration file %s not found - using build-in defaults...\n", configfile.c_str());
+    #endif
+  }else{
+    while (conf.good()){
+      getline(conf, tmpstr);
+      if (tmpstr[0] == '['){//new section? check if we care.
+        if (tmpstr == defstrh(CONFIGSECT)){acc_comm = true;}else{acc_comm = false;}
+      }else{
+        if (!acc_comm){break;}//skip all lines in this section if we do not care about it
+        foundeq = tmpstr.find('=');
+        if (foundeq != std::string::npos){
+          if ((tmpstr.substr(0, foundeq) == "port") && !ignore_port){listen_port = atoi(tmpstr.substr(foundeq+1).c_str());}
+          if ((tmpstr.substr(0, foundeq) == "interface") && !ignore_interface){interface = tmpstr.substr(foundeq+1);}
+          if ((tmpstr.substr(0, foundeq) == "username") && !ignore_user){username = tmpstr.substr(foundeq+1);}
+          if ((tmpstr.substr(0, foundeq) == "daemon") && !ignore_daemon){daemon_mode = true;}
+          if ((tmpstr.substr(0, foundeq) == "nodaemon") && !ignore_daemon){daemon_mode = false;}
+        }//found equals sign
+      }//section contents
+    }//configfile line loop
+  }//configuration
+
+  //setup a new server socket, for the correct interface and port
   server_socket = DDV::ServerSocket(listen_port, interface);
   #if DEBUG >= 3
   fprintf(stderr, "Made a listening socket on %s:%i...\n", interface.c_str(), listen_port);
   #endif
   if (server_socket.connected()){
+    //if setup success, enter daemon mode if requested
     if (daemon_mode){
       daemon(1, 0);
       #if DEBUG >= 3
@@ -75,23 +131,41 @@ int main(int argc, char ** argv){
     #endif
     return 1;
   }
-  int status;
+
-  while (server_socket.connected()){
+  if (username != "root"){
-    waitpid((pid_t)-1, &status, WNOHANG);
+    struct passwd * user_info = getpwnam(username.c_str());
-    CONN_fd = server_socket.accept();
+    if (!user_info){
-    if (CONN_fd.connected()){
+      #if DEBUG >= 1
-      pid_t myid = fork();
+      fprintf(stderr, "Error: could not setuid %s: could not get PID\n", username.c_str());
-      if (myid == 0){
+      #endif
-        break;
+      return 1;
+    }else{
+      if (setuid(user_info->pw_uid) != 0){
+        #if DEBUG >= 1
+        fprintf(stderr, "Error: could not setuid %s: not allowed\n", username.c_str());
+        #endif
       }else{
         #if DEBUG >= 3
-        fprintf(stderr, "Spawned new process %i for socket %i\n", (int)myid, CONN_fd.getSocket());
+        fprintf(stderr, "Changed user to %s\n", username.c_str());
         #endif
       }
     }
   }
-  if (!server_socket.connected()){
+
-    return 0;
+  int status;
-  }
+  while (server_socket.connected()){
-  return MAINHANDLER(CONN_fd);
+    while (waitpid((pid_t)-1, &status, WNOHANG) > 0){}//clean up all child processes
-}
+    S = server_socket.accept();
+    if (S.connected()){//check if the new connection is valid
+      pid_t myid = fork();
+      if (myid == 0){//if new child, start MAINHANDLER
+        return MAINHANDLER(S);
+      }else{//otherwise, do nothing or output debugging text
+        #if DEBUG >= 3
+        fprintf(stderr, "Spawned new process %i for socket %i\n", (int)myid, S.getSocket());
+        #endif
+      }
+    }
+  }//while connected
+  return 0;
+}//main