properly deal with client sending chunked data

rofl0r · rofl0r · commit eced6822f8b2 · 2022-02-13T21:11:37.000Z
this fixes OPTIONS requests sent from apache SVN client using their native HTTP proxy support. closes tinyproxy#421 tested with `svn info http://svnmir.bme.freebsd.org/ports/`
diff --git a/src/reqs.c b/src/reqs.c
@@ -523,7 +523,7 @@ static struct request_s *process_request (struct conn_s *connptr,
  * server headers can be processed.
  *	- rjkaes
  */
-static int pull_client_data (struct conn_s *connptr, long int length)
+static int pull_client_data (struct conn_s *connptr, long int length, int iehack)
 {
         char *buffer;
         ssize_t len;
@@ -548,39 +548,75 @@ static int pull_client_data (struct conn_s *connptr, long int length)
                 length -= len;
         } while (length > 0);
 
-        /*
-         * BUG FIX: Internet Explorer will leave two bytes (carriage
-         * return and line feed) at the end of a POST message.  These
-         * need to be eaten for tinyproxy to work correctly.
-         */
-        ret = socket_nonblocking (connptr->client_fd);
-        if (ret != 0) {
-                log_message(LOG_ERR, "Failed to set the client socket "
-                            "to non-blocking: %s", strerror(errno));
-                goto ERROR_EXIT;
+        if (iehack) {
+                /*
+                 * BUG FIX: Internet Explorer will leave two bytes (carriage
+                 * return and line feed) at the end of a POST message.  These
+                 * need to be eaten for tinyproxy to work correctly.
+                 */
+                ret = socket_nonblocking (connptr->client_fd);
+                if (ret != 0) {
+                        log_message(LOG_ERR, "Failed to set the client socket "
+                                    "to non-blocking: %s", strerror(errno));
+                        goto ERROR_EXIT;
+                }
+        
+                len = recv (connptr->client_fd, buffer, 2, MSG_PEEK);
+        
+                ret = socket_blocking (connptr->client_fd);
+                if (ret != 0) {
+                        log_message(LOG_ERR, "Failed to set the client socket "
+                                    "to blocking: %s", strerror(errno));
+                        goto ERROR_EXIT;
+                }
+        
+                if (len < 0 && errno != EAGAIN)
+                        goto ERROR_EXIT;
+        
+                if ((len == 2) && CHECK_CRLF (buffer, len)) {
+                        ssize_t bytes_read;
+        
+                        bytes_read = read (connptr->client_fd, buffer, 2);
+                        if (bytes_read == -1) {
+                                log_message
+                                        (LOG_WARNING,
+                                         "Could not read two bytes from POST message");
+                        }
+                }
         }
 
-        len = recv (connptr->client_fd, buffer, 2, MSG_PEEK);
+        safefree (buffer);
+        return 0;
 
-        ret = socket_blocking (connptr->client_fd);
-        if (ret != 0) {
-                log_message(LOG_ERR, "Failed to set the client socket "
-                            "to blocking: %s", strerror(errno));
-                goto ERROR_EXIT;
-        }
+ERROR_EXIT:
+        safefree (buffer);
+        return -1;
+}
 
-        if (len < 0 && errno != EAGAIN)
-                goto ERROR_EXIT;
+/* pull chunked client data */
+static int pull_client_data_chunked (struct conn_s *connptr) {
+        char *buffer = 0;
+        ssize_t len;
+        long chunklen;
+
+        while(1) {
+                if (buffer) safefree(buffer);
+                len = readline (connptr->client_fd, &buffer);
 
-        if ((len == 2) && CHECK_CRLF (buffer, len)) {
-                ssize_t bytes_read;
+                if (len <= 0)
+                        goto ERROR_EXIT;
 
-                bytes_read = read (connptr->client_fd, buffer, 2);
-                if (bytes_read == -1) {
-                        log_message
-                                (LOG_WARNING,
-                                 "Could not read two bytes from POST message");
+                if (!connptr->error_variables) {
+                        if (safe_write (connptr->server_fd, buffer, len) < 0)
+                                goto ERROR_EXIT;
                 }
+
+                chunklen = strtol (buffer, (char**)0, 16);
+
+                if (pull_client_data (connptr, chunklen+2, 0) < 0)
+                        goto ERROR_EXIT;
+
+                if(!chunklen) break;
         }
 
         safefree (buffer);
@@ -787,7 +823,7 @@ static int remove_connection_headers (orderedmap hashofheaders)
 
 /*
  * If there is a Content-Length header, then return the value; otherwise, return
- * a negative number.
+ * -1.
  */
 static long get_content_length (orderedmap hashofheaders)
 {
@@ -802,6 +838,13 @@ static long get_content_length (orderedmap hashofheaders)
         return content_length;
 }
 
+static int is_chunked_transfer (orderedmap hashofheaders)
+{
+        char *data;
+        data = orderedmap_find (hashofheaders, "transfer-encoding");
+        return data ? !strcmp (data, "chunked") : 0;
+}
+
 /*
  * Search for Via header in a hash of headers and either write a new Via
  * header, or append our information to the end of an existing Via header.
@@ -896,6 +939,10 @@ process_client_headers (struct conn_s *connptr, orderedmap hashofheaders)
          */
         connptr->content_length.client = get_content_length (hashofheaders);
 
+        /* Check whether client sends chunked data. */
+        if (connptr->content_length.client == -1 && is_chunked_transfer (hashofheaders))
+                connptr->content_length.client = -2;
+
         /*
          * See if there is a "Connection" header.  If so, we need to do a bit
          * of processing. :)
@@ -960,8 +1007,9 @@ process_client_headers (struct conn_s *connptr, orderedmap hashofheaders)
 PULL_CLIENT_DATA:
         if (connptr->content_length.client > 0) {
                 ret = pull_client_data (connptr,
-                                        connptr->content_length.client);
-        }
+                                        connptr->content_length.client, 1);
+        } else if (connptr->content_length.client == -2)
+                ret = pull_client_data_chunked (connptr);
 
         return ret;
 }
