/**
* Handler for reading the GOAWAY frame after we know that
* the frame is such.
* The function waits for the full frame and then changes status
* of the session.
*
* @param session SPDY_Session whose read buffer is used.
*/
static void
spdyf_handler_read_goaway (struct SPDY_Session *session)
{
struct SPDYF_Control_Frame *frame;
uint32_t last_good_stream_id;
uint32_t status_int;
enum SPDY_GOAWAY_STATUS status;
SPDYF_ASSERT(SPDY_SESSION_STATUS_WAIT_FOR_SUBHEADER == session->status,
"the function is called wrong");
frame = (struct SPDYF_Control_Frame *)session->frame_handler_cls;
if(frame->length > SPDY_MAX_SUPPORTED_FRAME_SIZE)
{
//this is a protocol error/attack
session->status = SPDY_SESSION_STATUS_IGNORE_BYTES;
return;
}
if(0 != frame->flags || 8 != frame->length)
{
//this is a protocol error
SPDYF_DEBUG("wrong GOAWAY received");
//anyway, it will be handled
}
if((session->read_buffer_offset - session->read_buffer_beginning) < frame->length)
{
//not all fields are received
//try later
return;
}
//mark that the session is almost closed
session->is_goaway_received = true;
if(8 == frame->length)
{
memcpy(&last_good_stream_id, session->read_buffer + session->read_buffer_beginning, 4);
last_good_stream_id = NTOH31(last_good_stream_id);
session->read_buffer_beginning += 4;
memcpy(&status_int, session->read_buffer + session->read_buffer_beginning, 4);
status = ntohl(status_int);
session->read_buffer_beginning += 4;
//TODO do something with last_good
//SPDYF_DEBUG("Received GOAWAY; status=%i; lastgood=%i",status,last_good_stream_id);
//do something according to the status
//TODO
switch(status)
{
case SPDY_GOAWAY_STATUS_OK:
break;
case SPDY_GOAWAY_STATUS_PROTOCOL_ERROR:
break;
case SPDY_GOAWAY_STATUS_INTERNAL_ERROR:
break;
}
//SPDYF_DEBUG("goaway received: status %i", status);
}
session->status = SPDY_SESSION_STATUS_WAIT_FOR_HEADER;
free(frame);
}
/**
* Handler for reading RST_STREAM frames. After receiving the frame
* the stream moves into closed state and status
* of the session is changed. Frames, belonging to this stream, which
* are still at the output queue, will be ignored later.
*
* @param session SPDY_Session whose read buffer is used.
*/
static void
spdyf_handler_read_rst_stream (struct SPDY_Session *session)
{
struct SPDYF_Control_Frame *frame;
uint32_t stream_id;
int32_t status_int;
//enum SPDY_RST_STREAM_STATUS status; //for debug
struct SPDYF_Stream *stream;
SPDYF_ASSERT(SPDY_SESSION_STATUS_WAIT_FOR_SUBHEADER == session->status,
"the function is called wrong");
frame = (struct SPDYF_Control_Frame *)session->frame_handler_cls;
if(0 != frame->flags || 8 != frame->length)
{
//this is a protocol error
SPDYF_DEBUG("wrong RST_STREAM received");
//ignore as a large frame
session->status = SPDY_SESSION_STATUS_IGNORE_BYTES;
return;
}
if((session->read_buffer_offset - session->read_buffer_beginning) < frame->length)
{
//not all fields are received
//try later
return;
}
memcpy(&stream_id, session->read_buffer + session->read_buffer_beginning, 4);
stream_id = NTOH31(stream_id);
session->read_buffer_beginning += 4;
memcpy(&status_int, session->read_buffer + session->read_buffer_beginning, 4);
//status = ntohl(status_int); //for debug
session->read_buffer_beginning += 4;
session->status = SPDY_SESSION_STATUS_WAIT_FOR_HEADER;
free(frame);
//mark the stream as closed
stream = session->streams_head;
while(NULL != stream)
{
if(stream_id == stream->stream_id)
{
stream->is_in_closed = true;
stream->is_out_closed = true;
break;
}
stream = stream->next;
}
//SPDYF_DEBUG("Received RST_STREAM; status=%i; id=%i",status,stream_id);
//do something according to the status
//TODO
/*switch(status)
{
case SPDY_RST_STREAM_STATUS_PROTOCOL_ERROR:
break;
}*/
}
int
SPDYF_stream_new (struct SPDY_Session *session)
{
uint32_t stream_id;
uint32_t assoc_stream_id;
uint8_t priority;
uint8_t slot;
size_t buffer_pos = session->read_buffer_beginning;
struct SPDYF_Stream *stream;
struct SPDYF_Control_Frame *frame;
if((session->read_buffer_offset - session->read_buffer_beginning) < 10)
{
//not all fields are received to create new stream
return SPDY_NO;
}
frame = (struct SPDYF_Control_Frame *)session->frame_handler_cls;
//get stream id of the new stream
memcpy(&stream_id, session->read_buffer + session->read_buffer_beginning, 4);
stream_id = NTOH31(stream_id);
session->read_buffer_beginning += 4;
if(stream_id <= session->last_in_stream_id || 0==(stream_id % 2))
{
//wrong stream id sent by client
//GOAWAY with PROTOCOL_ERROR MUST be sent
//TODO
//ignore frame
session->frame_handler = &SPDYF_handler_ignore_frame;
return SPDY_NO;
}
else if(session->is_goaway_sent)
{
//the client is not allowed to create new streams anymore
//we MUST ignore the frame
session->frame_handler = &SPDYF_handler_ignore_frame;
return SPDY_NO;
}
//set highest stream id for session
session->last_in_stream_id = stream_id;
//get assoc stream id of the new stream
//this value is used with SPDY PUSH, thus nothing to do with it here
memcpy(&assoc_stream_id, session->read_buffer + session->read_buffer_beginning, 4);
assoc_stream_id = NTOH31(assoc_stream_id);
session->read_buffer_beginning += 4;
//get stream priority (3 bits)
//after it there are 5 bits that are not used
priority = *(uint8_t *)(session->read_buffer + session->read_buffer_beginning) >> 5;
session->read_buffer_beginning++;
//get slot (see SPDY draft)
slot = *(uint8_t *)(session->read_buffer + session->read_buffer_beginning);
session->read_buffer_beginning++;
if(NULL == (stream = malloc(sizeof(struct SPDYF_Stream))))
{
SPDYF_DEBUG("No memory");
//revert buffer state
session->read_buffer_beginning = buffer_pos;
return SPDY_NO;
}
memset(stream,0, sizeof(struct SPDYF_Stream));
stream->session = session;
stream->stream_id = stream_id;
stream->assoc_stream_id = assoc_stream_id;
stream->priority = priority;
stream->slot = slot;
stream->is_in_closed = (frame->flags & SPDY_SYN_STREAM_FLAG_FIN) != 0;
stream->flag_unidirectional = (frame->flags & SPDY_SYN_STREAM_FLAG_UNIDIRECTIONAL) != 0;
stream->is_out_closed = stream->flag_unidirectional;
stream->is_server_initiator = false;
stream->window_size = SPDYF_INITIAL_WINDOW_SIZE;
//put the stream to the list of streams for the session
DLL_insert(session->streams_head, session->streams_tail, stream);
return SPDY_YES;
}
