From 2758993bb2a30cda21c03bcbbcb85d2cf8e9d2ce Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Antti=20Sepp=C3=A4l=C3=A4?= <a.seppala@gmail.com>
Date: Sat, 20 Oct 2007 11:36:21 +0000
Subject: [PATCH] Robustify network protocols with more error checking.

---
 protocolext.c  | 24 +++++++++++++++++++-----
 protocolhttp.c | 14 ++++++++++----
 protocoludp.c  | 22 +++++++++++++++++-----
 3 files changed, 46 insertions(+), 14 deletions(-)

diff --git a/protocolext.c b/protocolext.c
index 6f5c37a..a88962e 100644
--- a/protocolext.c
+++ b/protocolext.c
@@ -3,7 +3,7 @@
  *
  * See the README file for copyright information and how to reach the author.
  *
- * $Id: protocolext.c,v 1.10 2007/10/19 22:56:25 rahrenbe Exp $
+ * $Id: protocolext.c,v 1.11 2007/10/20 11:36:21 ajhseppa Exp $
  */
 
 #include <sys/wait.h>
@@ -187,6 +187,11 @@ void cIptvProtocolExt::TerminateCommand(void)
 int cIptvProtocolExt::Read(unsigned char* *BufferAddr)
 {
   //debug("cIptvProtocolExt::Read()\n");
+  // Error out if socket not initialized
+  if (socketDesc <= 0) {
+    error("ERROR: Invalid socket in %s\n", __FUNCTION__);
+    return -1;
+  }
   socklen_t addrlen = sizeof(sockAddr);
   // Set argument point to read buffer
   *BufferAddr = readBuffer;
@@ -203,14 +208,21 @@ int cIptvProtocolExt::Read(unsigned char* *BufferAddr)
   if (retval < 0) {
      char tmp[64];
      error("ERROR: select(): %s", strerror_r(errno, tmp, sizeof(tmp)));
-     return -1;
+     return retval;
      }
   // Check if data available
   else if (retval) {
      // Read data from socket
-     int len = recvfrom(socketDesc, readBuffer, readBufferLen, MSG_DONTWAIT,
-                        (struct sockaddr *)&sockAddr, &addrlen);
-     if ((len > 0) && (readBuffer[0] == 0x47)) {
+     int len = 0;
+     if (isActive)
+        len = recvfrom(socketDesc, readBuffer, readBufferLen, MSG_DONTWAIT,
+                       (struct sockaddr *)&sockAddr, &addrlen);
+     if (len < 0) {
+        char tmp[64];
+        error("ERROR: recvfrom(): %s", strerror_r(errno, tmp, sizeof(tmp)));
+        return len;
+        }
+     else if ((len > 0) && (readBuffer[0] == 0x47)) {
         // Set argument point to read buffer
         *BufferAddr = &readBuffer[0];
         return len;
@@ -256,6 +268,7 @@ bool cIptvProtocolExt::Open(void)
   OpenSocket();
   // Execute the external command
   ExecuteCommand();
+  isActive = true;
   return true;
 }
 
@@ -266,6 +279,7 @@ bool cIptvProtocolExt::Close(void)
   CloseSocket();
   // Terminate the external script
   TerminateCommand();
+  isActive = false;
   return true;
 }
 
diff --git a/protocolhttp.c b/protocolhttp.c
index 6e4337e..8da27fb 100644
--- a/protocolhttp.c
+++ b/protocolhttp.c
@@ -3,7 +3,7 @@
  *
  * See the README file for copyright information and how to reach the author.
  *
- * $Id: protocolhttp.c,v 1.12 2007/10/19 22:18:55 rahrenbe Exp $
+ * $Id: protocolhttp.c,v 1.13 2007/10/20 11:36:21 ajhseppa Exp $
  */
 
 #include <sys/types.h>
@@ -307,6 +307,11 @@ bool cIptvProtocolHttp::ProcessHeaders(void)
 int cIptvProtocolHttp::Read(unsigned char* *BufferAddr)
 {
   //debug("cIptvProtocolHttp::Read()\n");
+  // Error out if socket not initialized
+  if (socketDesc <= 0) {
+    error("ERROR: Invalid socket in %s\n", __FUNCTION__);
+    return -1;
+  }
   socklen_t addrlen = sizeof(sockAddr);
   // Set argument point to read buffer
   *BufferAddr = readBuffer;
@@ -323,13 +328,14 @@ int cIptvProtocolHttp::Read(unsigned char* *BufferAddr)
   if (retval < 0) {
      char tmp[64];
      error("ERROR: select(): %s", strerror_r(errno, tmp, sizeof(tmp)));
-     return -1;
+     return retval;
      }
   // Check if data available
   else if (retval) {
      // Read data from socket
-     return recvfrom(socketDesc, readBuffer, readBufferLen, MSG_DONTWAIT,
-                     (struct sockaddr *)&sockAddr, &addrlen);
+     if (isActive)
+        return recvfrom(socketDesc, readBuffer, readBufferLen, MSG_DONTWAIT,
+                        (struct sockaddr *)&sockAddr, &addrlen);
      }
   return 0;
 }
diff --git a/protocoludp.c b/protocoludp.c
index 7d32209..016dbf9 100644
--- a/protocoludp.c
+++ b/protocoludp.c
@@ -3,7 +3,7 @@
  *
  * See the README file for copyright information and how to reach the author.
  *
- * $Id: protocoludp.c,v 1.13 2007/10/19 22:18:55 rahrenbe Exp $
+ * $Id: protocoludp.c,v 1.14 2007/10/20 11:36:21 ajhseppa Exp $
  */
 
 #include <sys/types.h>
@@ -155,6 +155,11 @@ bool cIptvProtocolUdp::DropMulticast(void)
 int cIptvProtocolUdp::Read(unsigned char* *BufferAddr)
 {
   //debug("cIptvProtocolUdp::Read()\n");
+  // Error out if socket not initialized
+  if (socketDesc <= 0) {
+    error("ERROR: Invalid socket in %s\n", __FUNCTION__);
+    return -1;
+  }
   socklen_t addrlen = sizeof(sockAddr);
   // Set argument point to read buffer
   *BufferAddr = readBuffer;
@@ -171,14 +176,21 @@ int cIptvProtocolUdp::Read(unsigned char* *BufferAddr)
   if (retval < 0) {
      char tmp[64];
      error("ERROR: select(): %s", strerror_r(errno, tmp, sizeof(tmp)));
-     return -1;
+     return retval;
      }
   // Check if data available
   else if (retval) {
+     int len = 0;
      // Read data from socket
-     int len = recvfrom(socketDesc, readBuffer, readBufferLen, MSG_DONTWAIT,
-                        (struct sockaddr *)&sockAddr, &addrlen);
-     if ((len > 0) && (readBuffer[0] == 0x47)) {
+     if (isActive)
+        len = recvfrom(socketDesc, readBuffer, readBufferLen, MSG_DONTWAIT,
+                       (struct sockaddr *)&sockAddr, &addrlen);
+     if (len < 0) {
+        char tmp[64];
+        error("ERROR: recvfrom(): %s", strerror_r(errno, tmp, sizeof(tmp)));
+        return len;
+        }
+     else if ((len > 0) && (readBuffer[0] == 0x47)) {
         // Set argument point to read buffer
         *BufferAddr = &readBuffer[0];
         return len;