Re: [libmicrohttpd] Broken HTTP 1.0 and 0.9 support

[Christian Grothoff]

Hi!

I'm not sure about both of these.  My reading of the standard (and the 
principle of being permissive in general) is that if we receive an HTTP 
request with an "unknown" version number (i.e. 0.9 or 1.2) but we can process 
it, we should.  Moreover, if your server wants to do something else (say, not 
return 200 OK), you can (since the version number is exposed to you via the 
API).

Similarly, my reading of the standard is that if a client says "HTTP 1.0", it 
is completely OK to respond "and this server supports HTTP 1.1" as long as no 
1.1 features are used otherwise.


If you have any specific statements in say HTTP RFCs that contradict this, 
I'll be happy to give your patch strong consideration, but at this point I am 
not convinced that these changes would actually be an improvement.

Finally, I am not sure what exactly you're trying to do with the 0-byte 
response that you create in your patch (close the connection?), but I'm not 
sure it is the best (=simplest) way to do whatever you want to do.

My 2 cents

Christian

On Wednesday 21 April 2010 03:00:12 pm Geoffrey McRae wrote:
> Hi All,
> 
> I am one of the developers for XBMC where we are using your wonderful
> library for our web interface. It has come to my attention however that
> support for HTTP/1.0 and 0.9 is broken/wrong.
> 
> Currently 0.9 for requests it serves out an invalid " 200 OK" and the
> headers, which it should not.
> 
> For 1.0 it returns HTTP/1.1 in the response, which again is incorrect
> since we made a 1.0 request.
> 
> The following patch corrects both of these issues.
> 
> Kind Regards
> Geoffrey McRae (gnif)
> http://www.xbmc.org/
> 
> diff --git a/lib/libmicrohttpd/src/daemon/connection.c
> b/lib/libmicrohttpd/src/daemon/connection.c
> index ef47b1c..dc71be9 100644
> --- a/lib/libmicrohttpd/src/daemon/connection.c
> +++ b/lib/libmicrohttpd/src/daemon/connection.c
> @@ -577,13 +577,23 @@ build_header_response (struct MHD_Connection
> *connection)
>    enum MHD_ValueKind kind;
>    const char *reason_phrase;
> 
> +  if (strlen(connection->version) == 0)
> +    {
> +      data = MHD_pool_allocate (connection->pool, 0, MHD_YES);
> +      connection->write_buffer = data;
> +      connection->write_buffer_append_offset = 0;
> +      connection->write_buffer_send_offset = 0;
> +      connection->write_buffer_size = 0;
> +      return MHD_YES;
> +    }
> +
>    if (connection->state == MHD_CONNECTION_FOOTERS_RECEIVED)
>      {
>        add_extra_headers (connection);
>        reason_phrase = MHD_get_reason_phrase_for
> (connection->responseCode);
>        SPRINTF (code,
>                 "%s %u %s\r\n",
> -               MHD_HTTP_VERSION_1_1, connection->responseCode,
> reason_phrase);
> +               connection->version, connection->responseCode,
> reason_phrase);
>        off = strlen (code);
>        /* estimate size */
>        size = off + 2;           /* extra \r\n at the end */
>