Handle 1-character messages terminated with CR or LF correctly

Code cleanup and fix for Bug #83, "ngIRCd chokes on 1-character messages" in
function Handle_Buffer(): the buffer is now correctly cleared when ngIRCd
receives 1-character messages terminated with either CR or LF (in violation
to RFC 2812, section 2.3 "Messages", 5th paragraph).

diff --git a/ChangeLog b/ChangeLog
index 8fa83a7b71a3dcc3512eb4c64537751e105e68ce..921bbf6b5d7acac4d2cb1657b572483010201f97 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -12,6 +12,7 @@
 
 ngIRCd-dev
 
+  - Fixed Bug 83: ngIRCd chokes on 1-character messages.
   - Add support for modeless channels ("+channels").
     (Bryan Caldwell, Ali Shemiran)
 

diff --git a/src/ngircd/conn.c b/src/ngircd/conn.c
index 1696d5c5f62968d8d495576b4e1bc67947db66ee..d6542e23528ab48920ca787ddaa0de5140d21264 100644 (file)
--- a/src/ngircd/conn.c
+++ b/src/ngircd/conn.c
@@ -1218,11 +1218,13 @@ Read_Request( CONN_ID Idx )
 } /* Read_Request */
 
 
+/**
+ * Handle data in connection read-buffer.
+ * @return true if a reuqest was handled, false otherwise (and on errors).
+ */
 static bool
-Handle_Buffer( CONN_ID Idx )
+Handle_Buffer(CONN_ID Idx)
 {
-       /* Handle Data in Connections Read-Buffer.
-        * Return true if a reuqest was handled, false otherwise (also returned on errors). */
 #ifndef STRICT_RFC
        char *ptr1, *ptr2;
 #endif
@@ -1238,86 +1240,104 @@ Handle_Buffer( CONN_ID Idx )
        result = false;
        for (;;) {
                /* Check penalty */
-               if( My_Connections[Idx].delaytime > starttime) return result;
+               if (My_Connections[Idx].delaytime > starttime)
+                       return result;
 #ifdef ZLIB
-               /* unpack compressed data */
-               if ( Conn_OPTION_ISSET( &My_Connections[Idx], CONN_ZIP ))
-                       if( ! Unzip_Buffer( Idx )) return false;
+               /* Unpack compressed data, if compression is in use */
+               if (Conn_OPTION_ISSET(&My_Connections[Idx], CONN_ZIP)) {
+                       if (!Unzip_Buffer(Idx))
+                               return false;
+               }
 #endif
 
                if (0 == array_bytes(&My_Connections[Idx].rbuf))
                        break;
 
-               if (!array_cat0_temporary(&My_Connections[Idx].rbuf)) /* make sure buf is NULL terminated */
+               /* Make sure that the buffer is NULL terminated */
+               if (!array_cat0_temporary(&My_Connections[Idx].rbuf))
                        return false;
 
-               /* A Complete Request end with CR+LF, see RFC 2812. */
-               ptr = strstr( array_start(&My_Connections[Idx].rbuf), "\r\n" );
+               /* RFC 2812, section "2.3 Messages", 5th paragraph:
+                * "IRC messages are always lines of characters terminated
+                * with a CR-LF (Carriage Return - Line Feed) pair [...]". */
+               delta = 2;
+               ptr = strstr(array_start(&My_Connections[Idx].rbuf), "\r\n");
 
-               if( ptr ) delta = 2; /* complete request */
 #ifndef STRICT_RFC
-               else {
-                       /* Check for non-RFC-compliant request (only CR or LF)? Unfortunately,
-                        * there are quite a few clients that do this (incl. "mIRC" :-( */
-                       ptr1 = strchr( array_start(&My_Connections[Idx].rbuf), '\r' );
-                       ptr2 = strchr( array_start(&My_Connections[Idx].rbuf), '\n' );
+               if (!ptr) {
+                       /* Check for non-RFC-compliant request (only CR or
+                        * LF)? Unfortunately, there are quite a few clients
+                        * out there that do this -- incl. "mIRC" :-( */
                        delta = 1;
-                       if( ptr1 && ptr2 ) ptr = ptr1 > ptr2 ? ptr2 : ptr1;
-                       else if( ptr1 ) ptr = ptr1;
-                       else if( ptr2 ) ptr = ptr2;
+                       ptr1 = strchr(array_start(&My_Connections[Idx].rbuf), '\r');
+                       ptr2 = strchr(array_start(&My_Connections[Idx].rbuf), '\n');
+                       if (ptr1 && ptr2)
+                               ptr = ptr1 > ptr2 ? ptr2 : ptr1;
+                       else if (ptr1)
+                               ptr = ptr1;
+                       else if (ptr2)
+                               ptr = ptr2;
                }
 #endif
 
-               if( ! ptr )
+               if (!ptr)
                        break;
 
-               /* End of request found */
+               /* Complete (=line terminated) request found, handle it! */
                *ptr = '\0';
 
-               len = ( ptr - (char*) array_start(&My_Connections[Idx].rbuf)) + delta;
+               len = ptr - (char *)array_start(&My_Connections[Idx].rbuf) + delta;
 
-               if( len > ( COMMAND_LEN - 1 )) {
-                       /* Request must not exceed 512 chars (incl. CR+LF!), see
-                        * RFC 2812. Disconnect Client if this happens. */
-                       Log( LOG_ERR, "Request too long (connection %d): %d bytes (max. %d expected)!",
-                                               Idx, array_bytes(&My_Connections[Idx].rbuf), COMMAND_LEN - 1 );
-                       Conn_Close( Idx, NULL, "Request too long", true );
+               if (len > (COMMAND_LEN - 1)) {
+                       /* Request must not exceed 512 chars (incl. CR+LF!),
+                        * see RFC 2812. Disconnect Client if this happens. */
+                       Log(LOG_ERR,
+                           "Request too long (connection %d): %d bytes (max. %d expected)!",
+                           Idx, array_bytes(&My_Connections[Idx].rbuf),
+                           COMMAND_LEN - 1);
+                       Conn_Close(Idx, NULL, "Request too long", true);
                        return false;
                }
 
-               if (len <= 2) { /* request was empty (only '\r\n') */
-                       array_moveleft(&My_Connections[Idx].rbuf, 1, delta); /* delta is either 1 or 2 */
+               if (len <= delta) {
+                       /* Request is empty (only '\r\n', '\r' or '\n');
+                        * delta is 2 ('\r\n') or 1 ('\r' or '\n'), see above */
+                       array_moveleft(&My_Connections[Idx].rbuf, 1, len);
                        break;
                }
+
 #ifdef ZLIB
                /* remember if stream is already compressed */
                old_z = My_Connections[Idx].options & CONN_ZIP;
 #endif
 
                My_Connections[Idx].msg_in++;
-               if (!Parse_Request(Idx, (char*)array_start(&My_Connections[Idx].rbuf) ))
+               if (!Parse_Request
+                   (Idx, (char *)array_start(&My_Connections[Idx].rbuf)))
                        return false;
 
                result = true;
 
                array_moveleft(&My_Connections[Idx].rbuf, 1, len);
                LogDebug("Connection %d: %d bytes left in read buffer.",
-                   Idx, array_bytes(&My_Connections[Idx].rbuf));
+                        Idx, array_bytes(&My_Connections[Idx].rbuf));
 #ifdef ZLIB
-               if(( ! old_z ) && ( My_Connections[Idx].options & CONN_ZIP ) &&
-                               ( array_bytes(&My_Connections[Idx].rbuf) > 0 ))
-               {
-                       /* The last Command activated Socket-Compression.
-                        * Data that was read after that needs to be copied to Unzip-buf
-                        * for decompression */
-                       if (!array_copy( &My_Connections[Idx].zip.rbuf, &My_Connections[Idx].rbuf ))
+               if ((!old_z) && (My_Connections[Idx].options & CONN_ZIP) &&
+                   (array_bytes(&My_Connections[Idx].rbuf) > 0)) {
+                       /* The last command activated socket compression.
+                        * Data that was read after that needs to be copied
+                        * to the unzip buffer for decompression: */
+                       if (!array_copy
+                           (&My_Connections[Idx].zip.rbuf,
+                            &My_Connections[Idx].rbuf))
                                return false;
 
                        array_trunc(&My_Connections[Idx].rbuf);
-                       LogDebug("Moved already received data (%u bytes) to uncompression buffer.",
-                                                               array_bytes(&My_Connections[Idx].zip.rbuf));
+                       LogDebug
+                           ("Moved already received data (%u bytes) to uncompression buffer.",
+                            array_bytes(&My_Connections[Idx].zip.rbuf));
                }
-#endif /* ZLIB */
+#endif
        }
        return result;
 } /* Handle_Buffer */