improved MHD handling of client programmer bugs in handling of upload data

author: Christian Grothoff <christian@grothoff.org> 2008-04-13 03:36:12 +0000
committer: Christian Grothoff <christian@grothoff.org> 2008-04-13 03:36:12 +0000
commit: fe43cf59f6679a0b73b0ab980a9b120f9a6e2e08 (patch)
tree: d9ef2266bb365b0c1e3d2316d61ec04cd7ebf54a
parent: 1ea6af115589702923a795c4776135c3b1b37d06 (diff)
download: libmicrohttpd-fe43cf59f6679a0b73b0ab980a9b120f9a6e2e08.tar.gz
libmicrohttpd-fe43cf59f6679a0b73b0ab980a9b120f9a6e2e08.zip
7 files changed, 62 insertions, 26 deletions
diff --git a/ChangeLog b/ChangeLog
index 8d9d552b..3432bcde 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sat Apr 12 21:34:26 MDT 2008
+         Generate an internal server error if the programmer fails
+         to handle upload data correctly.  Tweaked testcases to
+         avoid running into the problem in the testcases. -CG
 Sat Apr 12 15:14:05 MDT 2008
         Restructured the code (curl-testcases and zzuf testcases
         are now in different directories; code examples are in
@@ -9,8 +14,8 @@ Sat Apr 12 15:14:05 MDT 2008
         errors (such as request too large and malformed requests).
         Without that flag, the webpages returned will still be
         empty.
-         Added zzuf-based fuzzing-testcases (these require the
+         Started to add zzuf-based fuzzing-testcases (these require 
-         zzuf and socat binaries to be installed).
+         the zzuf and socat binaries to be installed). -CG
 Fri Apr 11 20:20:34 MDT 2008
         I hereby dub libmicrohttpd a GNU package. -Richard Stallman
diff --git a/src/daemon/connection.c b/src/daemon/connection.c
index eb97c6b9..21768b5a 100644
--- a/src/daemon/connection.c
+++ b/src/daemon/connection.c
@@ -1,6 +1,6 @@
 /*
     This file is part of libmicrohttpd
-     (C) 2007 Daniel Pittman and Christian Grothoff
+     (C) 2007, 2008 Daniel Pittman and Christian Grothoff
     This library is free software; you can redistribute it and/or
     modify it under the terms of the GNU Lesser General Public
@@ -82,6 +82,18 @@
 #define REQUEST_MALFORMED ""
 #endif
+/**
+ * Response text used when there is an internal server error.
+ *
+ * Intentionally empty here to keep our memory footprint
+ * minimal.
+ */
+#if HAVE_MESSAGES
+#define INTERNAL_ERROR "<html><head><title>Internal server error</title></head><body>Some programmer needs to study the manual more carefully.</body></html>"
+#else
+#define INTERNAL_ERROR ""
+#endif
 #define EXTRA_CHECKS MHD_YES
 #if EXTRA_CHECKS
@@ -676,7 +688,29 @@ MHD_connection_get_fdset (struct MHD_Connection *connection,
          break;
        case MHD_CONNECTION_CONTINUE_SENT:
          if (connection->read_buffer_offset == connection->read_buffer_size)
-            try_grow_read_buffer (connection);
+            {
+              if ((MHD_YES != try_grow_read_buffer (connection)) &&
+                  (0 != (connection->daemon->options &
+                         (MHD_USE_SELECT_INTERNALLY |
+                          MHD_USE_THREAD_PER_CONNECTION))))
+                {
+                  /* failed to grow the read buffer, and the 
+                     client which is supposed to handle the
+                     received data in a *blocking* fashion
+                     (in this mode) did not handle the data as
+                     it was supposed to!
+                     => we would either have to do busy-waiting 
+                     (on the client, which would likely fail),
+                     or if we do nothing, we would just timeout
+                     on the connection (if a timeout is even
+                     set!).
+                     Solution: we kill the connection with an error */
+                  transmit_error_response (connection,
+                                           MHD_HTTP_INTERNAL_SERVER_ERROR,
+                                           INTERNAL_ERROR);
+                  continue;
+                }
+            }
          if ((connection->read_buffer_offset < connection->read_buffer_size)
              && (MHD_NO == connection->read_closed))
            do_fd_set (fd, read_fd_set, max_fd);
diff --git a/src/examples/Makefile.am b/src/examples/Makefile.am
index fd515a56..4111fa1e 100644
--- a/src/examples/Makefile.am
+++ b/src/examples/Makefile.am
@@ -4,13 +4,18 @@ INCLUDES = -I$(top_srcdir)/src/include
 # example programs
-noinst_PROGRAMS = minimal_example fileserver_example
+noinst_PROGRAMS = minimal_example querystring_example fileserver_example
 minimal_example_SOURCES = \
 minimal_example.c 
 minimal_example_LDADD = \
 $(top_builddir)/src/daemon/libmicrohttpd.la 
+querystring_example_SOURCES = \
+ querystring_example.c 
+querystring_example_LDADD = \
+ $(top_builddir)/src/daemon/libmicrohttpd.la 
 fileserver_example_SOURCES = \
 fileserver_example.c 
 fileserver_example_LDADD = \
diff --git a/src/testcurl/daemontest_large_put.c b/src/testcurl/daemontest_large_put.c
index b0c7bf37..414ddf76 100644
--- a/src/testcurl/daemontest_large_put.c
+++ b/src/testcurl/daemontest_large_put.c
@@ -41,8 +41,12 @@ static int oneone;
 * Do not make this much larger since we will hit the
 * MHD default buffer limit and the test code is not
 * written for incremental upload processing...
+ * (larger values will likely cause MHD to generate
+ * an internal server error -- which would be avoided
+ * by writing the putBuffer method in a more general
+ * fashion).
 */
-#define PUT_SIZE (512 * 1024)
+#define PUT_SIZE (256 * 1024)
 static char *put_buffer;
@@ -390,11 +394,8 @@ main (int argc, char *const *argv)
    return 2;
  put_buffer = malloc (PUT_SIZE);
  memset (put_buffer, 1, PUT_SIZE);
-  if (0)
+  errorCount += testInternalPut ();
-    {
+  errorCount += testMultithreadedPut ();
-      errorCount += testInternalPut ();
-      errorCount += testMultithreadedPut ();
-    }
  errorCount += testExternalPut ();
  free (put_buffer);
  if (errorCount != 0)
diff --git a/src/testcurl/daemontest_postform.c b/src/testcurl/daemontest_postform.c
index 4142b138..0940e0ac 100644
--- a/src/testcurl/daemontest_postform.c
+++ b/src/testcurl/daemontest_postform.c
@@ -392,11 +392,8 @@ main (int argc, char *const *argv)
  if (0 != curl_global_init (CURL_GLOBAL_WIN32))
    return 2;
  errorCount += testInternalPost ();
-  if (0)
+  errorCount += testMultithreadedPost ();
-    {
+  errorCount += testExternalPost ();
-      errorCount += testMultithreadedPost ();
-      errorCount += testExternalPost ();
-    }
  if (errorCount != 0)
    fprintf (stderr, "Error (code: %u)\n", errorCount);
  curl_global_cleanup ();
diff --git a/src/testcurl/daemontest_put.c b/src/testcurl/daemontest_put.c
index e1f89402..3ce7d371 100644
--- a/src/testcurl/daemontest_put.c
+++ b/src/testcurl/daemontest_put.c
@@ -363,11 +363,8 @@ main (int argc, char *const *argv)
  if (0 != curl_global_init (CURL_GLOBAL_WIN32))
    return 2;
  errorCount += testInternalPut ();
-  if (0)
+  errorCount += testMultithreadedPut ();
-    {
+  errorCount += testExternalPut ();
-      errorCount += testMultithreadedPut ();
-      errorCount += testExternalPut ();
-    }
  if (errorCount != 0)
    fprintf (stderr, "Error (code: %u)\n", errorCount);
  curl_global_cleanup ();
diff --git a/src/testcurl/daemontest_put_chunked.c b/src/testcurl/daemontest_put_chunked.c
index 0cc3eb8f..f613882b 100644
--- a/src/testcurl/daemontest_put_chunked.c
+++ b/src/testcurl/daemontest_put_chunked.c
@@ -371,11 +371,8 @@ main (int argc, char *const *argv)
  if (0 != curl_global_init (CURL_GLOBAL_WIN32))
    return 2;
  errorCount += testInternalPut ();
-  if (0)
+  errorCount += testMultithreadedPut ();
-    {
+  errorCount += testExternalPut ();
-      errorCount += testMultithreadedPut ();
-      errorCount += testExternalPut ();
-    }
  if (errorCount != 0)
    fprintf (stderr, "Error (code: %u)\n", errorCount);
  curl_global_cleanup ();
author	Christian Grothoff <christian@grothoff.org>	2008-04-13 03:36:12 +0000
committer	Christian Grothoff <christian@grothoff.org>	2008-04-13 03:36:12 +0000
commit	fe43cf59f6679a0b73b0ab980a9b120f9a6e2e08 (patch)
tree	d9ef2266bb365b0c1e3d2316d61ec04cd7ebf54a
parent	1ea6af115589702923a795c4776135c3b1b37d06 (diff)
download	libmicrohttpd-fe43cf59f6679a0b73b0ab980a9b120f9a6e2e08.tar.gz libmicrohttpd-fe43cf59f6679a0b73b0ab980a9b120f9a6e2e08.zip