Added validation for source addresses of socket data.

HISTORY

@@ -146,3 +146,4 @@ VDR Plugin 'iptv' Revision History
 
 - Renamed Sid scanner to section id scanner and added
   experimental Tid/Nid support into it.
+- Added validation for source addresses of socket data.

protocolext.c

@@ -109,7 +109,7 @@ bool cIptvProtocolExt::Open(void)
   if (!strlen(*scriptFile))
      return false;
   // Create the listening socket
-  OpenSocket(socketPort);
+  OpenSocket(INADDR_LOOPBACK, socketPort);
   // Execute the external script
   ExecuteScript();
   isActive = true;

protocolhttp.c

@@ -40,9 +40,6 @@ bool cIptvProtocolHttp::Connect(void)
   debug("cIptvProtocolHttp::Connect()\n");
   // Check that stream address is valid
   if (!isActive && !isempty(streamAddr) && !isempty(streamPath)) {
-     // Ensure that socket is valid
-     OpenSocket(socketPort);
-
      // First try only the IP address
      sockAddr.sin_addr.s_addr = inet_addr(streamAddr);
 
@@ -61,6 +58,9 @@ bool cIptvProtocolHttp::Connect(void)
         sockAddr.sin_addr.s_addr = inet_addr(*host->h_addr_list);
         }
 
+     // Ensure that socket is valid
+     OpenSocket(sockAddr.sin_addr.s_addr, socketPort);
+
      int err = connect(socketDesc, (struct sockaddr *)&sockAddr, sizeof(sockAddr));
      // Non-blocking sockets always report in-progress error when connected
      ERROR_IF_FUNC(err < 0 && errno != EINPROGRESS, "connect()", CloseSocket(), return false);

protocoludp.c

@@ -39,7 +39,7 @@ bool cIptvProtocolUdp::JoinMulticast(void)
   // Check that stream address is valid
   if (!isActive && !isempty(streamAddr)) {
      // Ensure that socket is valid
-     OpenSocket(socketPort);
+     OpenSocket(inet_addr(streamAddr), socketPort);
      // Join a new multicast group
      struct ip_mreq mreq;
      mreq.imr_multiaddr.s_addr = inet_addr(streamAddr);
@@ -59,7 +59,7 @@ bool cIptvProtocolUdp::DropMulticast(void)
   // Check that stream address is valid
   if (isActive && !isempty(streamAddr)) {
       // Ensure that socket is valid
-      OpenSocket(socketPort);
+      OpenSocket(inet_addr(streamAddr), socketPort);
       // Drop the multicast group
       struct ip_mreq mreq;
       mreq.imr_multiaddr.s_addr = inet_addr(streamAddr);

socket.c

@@ -18,11 +18,13 @@
 #include "socket.h"
 
 cIptvSocket::cIptvSocket()
-: socketPort(0),
-  socketDesc(-1),
+: socketDesc(-1),
+  socketPort(0),
+  inetAddr(INADDR_NONE),
   isActive(false)
 {
   debug("cIptvSocket::cIptvSocket()\n");
+  memset(&sockAddr, 0, sizeof(sockAddr));
 }
 
 cIptvSocket::~cIptvSocket()
@@ -32,9 +34,11 @@ cIptvSocket::~cIptvSocket()
   CloseSocket();
 }
 
-bool cIptvSocket::OpenSocket(const int Port, const bool isUdp)
+bool cIptvSocket::OpenSocket(const in_addr_t InetAddr, const int Port, const bool isUdp)
 {
   debug("cIptvSocket::OpenSocket()\n");
+  if (inetAddr != InetAddr)
+     inetAddr = InetAddr;
   // If socket is there already and it is bound to a different port, it must
   // be closed first
   if (Port != socketPort) {
@@ -57,7 +61,7 @@ bool cIptvSocket::OpenSocket(const int Port, const bool isUdp)
      ERROR_IF_FUNC(setsockopt(socketDesc, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) < 0, "setsockopt()",
                    CloseSocket(), return false);
      // Bind socket
-     memset(&sockAddr, '\0', sizeof(sockAddr));
+     memset(&sockAddr, 0, sizeof(sockAddr));
      sockAddr.sin_family = AF_INET;
      sockAddr.sin_port = htons((uint16_t)(Port & 0xFFFF));
      sockAddr.sin_addr.s_addr = htonl(INADDR_ANY);
@@ -78,6 +82,9 @@ void cIptvSocket::CloseSocket(void)
   if (socketDesc >= 0) {
      close(socketDesc);
      socketDesc = -1;
+     socketPort = 0;
+     inetAddr = INADDR_NONE;
+     memset(&sockAddr, 0, sizeof(sockAddr));
      }
 }
 
@@ -92,10 +99,10 @@ cIptvUdpSocket::~cIptvUdpSocket()
   debug("cIptvUdpSocket::~cIptvUdpSocket()\n");
 }
 
-bool cIptvUdpSocket::OpenSocket(const int Port)
+bool cIptvUdpSocket::OpenSocket(const in_addr_t InetAddr, const int Port)
 {
   debug("cIptvUdpSocket::OpenSocket()\n");
-  return cIptvSocket::OpenSocket(Port, true);
+  return cIptvSocket::OpenSocket(InetAddr, Port, true);
 }
 
 int cIptvUdpSocket::Read(unsigned char* BufferAddr, unsigned int BufferLen)
@@ -108,13 +115,35 @@ int cIptvUdpSocket::Read(unsigned char* BufferAddr, unsigned int BufferLen)
      }
   socklen_t addrlen = sizeof(sockAddr);
   int len = 0;
+  struct msghdr msgh;
+  struct cmsghdr *cmsg;
+  struct iovec iov;
+  char cbuf[256];
+  // Initialize iov and msgh structures
+  memset(&msgh, 0, sizeof(struct msghdr));
+  iov.iov_base = BufferAddr;
+  iov.iov_len = BufferLen;
+  msgh.msg_control = cbuf;
+  msgh.msg_controllen = sizeof(cbuf);
+  msgh.msg_name = &sockAddr;
+  msgh.msg_namelen = addrlen;
+  msgh.msg_iov  = &iov;
+  msgh.msg_iovlen = 1;
+  msgh.msg_flags = 0;
   // Read data from socket
   if (isActive && socketDesc && BufferAddr && (BufferLen > 0))
-     len = (int)recvfrom(socketDesc, BufferAddr, BufferLen, MSG_DONTWAIT,
-                    (struct sockaddr *)&sockAddr, &addrlen);
-  if ((len > 0) && (BufferAddr[0] == TS_SYNC_BYTE)) {
+     len = (int)recvmsg(socketDesc, &msgh, MSG_DONTWAIT);
+  if (len < 0)
+     return -1;
+  else if (len > 0) {
+     // Process auxiliary received data
+     for (cmsg = CMSG_FIRSTHDR(&msgh); cmsg != NULL; cmsg = CMSG_NXTHDR(&msgh, cmsg)) {
+         if ((cmsg->cmsg_level == SOL_IP) && (cmsg->cmsg_type == IP_PKTINFO)) {
+            struct in_pktinfo *i = (struct in_pktinfo *)CMSG_DATA(cmsg);
+            // Validate source address
+            if (i->ipi_addr.s_addr == inetAddr) {
+               if (BufferAddr[0] == TS_SYNC_BYTE)
                   return len;
-     }
                else if (len > 3) {
                   // http://www.networksorcery.com/enp/rfc/rfc2250.txt
                   // version
@@ -145,6 +174,11 @@ int cIptvUdpSocket::Read(unsigned char* BufferAddr, unsigned int BufferLen)
                   }
                return 0;
                }
+            }
+         }
+     }
+  return 0;
+}
 
 // TCP socket class
 cIptvTcpSocket::cIptvTcpSocket()
@@ -157,10 +191,10 @@ cIptvTcpSocket::~cIptvTcpSocket()
   debug("cIptvTcpSocket::~cIptvTcpSocket()\n");
 }
 
-bool cIptvTcpSocket::OpenSocket(const int Port)
+bool cIptvTcpSocket::OpenSocket(const in_addr_t InetAddr, const int Port)
 {
   debug("cIptvTcpSocket::OpenSocket()\n");
-  return cIptvSocket::OpenSocket(Port, false);
+  return cIptvSocket::OpenSocket(InetAddr, Port, false);
 }
 
 int cIptvTcpSocket::Read(unsigned char* BufferAddr, unsigned int BufferLen)
@@ -171,10 +205,13 @@ int cIptvTcpSocket::Read(unsigned char* BufferAddr, unsigned int BufferLen)
      error("Invalid socket in %s\n", __FUNCTION__);
      return -1;
      }
+  int len = 0;
   socklen_t addrlen = sizeof(sockAddr);
   // Read data from socket
   if (isActive && socketDesc && BufferAddr && (BufferLen > 0))
-     return (int)recvfrom(socketDesc, BufferAddr, BufferLen, MSG_DONTWAIT,
+     len = recvfrom(socketDesc, BufferAddr, BufferLen, MSG_DONTWAIT,
                     (struct sockaddr *)&sockAddr, &addrlen);
-  return 0;
+  //if (inetAddr != sockAddr.sin_addr.s_addr)
+  //   return -1;
+  return len;
 }

socket.h

@@ -12,13 +12,14 @@
 
 class cIptvSocket {
 protected:
-  int socketPort;
   int socketDesc;
+  int socketPort;
+  in_addr_t inetAddr;
   struct sockaddr_in sockAddr;
   bool isActive;
 
 protected:
-  bool OpenSocket(const int Port, const bool isUdp);
+  bool OpenSocket(const in_addr_t InetAddr, const int Port, const bool isUdp);
   void CloseSocket(void);
 
 public:
@@ -31,7 +32,7 @@ public:
   cIptvUdpSocket();
   virtual ~cIptvUdpSocket();
   virtual int Read(unsigned char* BufferAddr, unsigned int BufferLen);
-  bool OpenSocket(const int Port);
+  bool OpenSocket(const in_addr_t InetAddr, const int Port);
 };
 
 class cIptvTcpSocket : public cIptvSocket {
@@ -39,7 +40,7 @@ public:
   cIptvTcpSocket();
   virtual ~cIptvTcpSocket();
   virtual int Read(unsigned char* BufferAddr, unsigned int BufferLen);
-  bool OpenSocket(const int Port);
+  bool OpenSocket(const in_addr_t InetAddr, const int Port);
 };
 
 #endif // __IPTV_SOCKET_H