Mirrors/libwebsockets
1
0
Fork 0
mirror of https://github.com/warmcat/libwebsockets.git synced 2025-03-16 00:00:07 +01:00
Code Issues Releases Wiki Activity
libwebsockets/lib/client-parser.c
Andy Green f7248f8dfa update ping test client and stop exposing payload to extensions 
Ping and Pong payload in control messages need to be
above the fray of extension payload munging

Signed-off-by: Andy Green <andy.green@linaro.org>
2013-01-16 15:12:33 +08:00

524 lines
14 KiB
C
Raw Blame History

/*
* libwebsockets - small server side websockets and web server implementation
*
* Copyright (C) 2010-2013 Andy Green <andy@warmcat.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation:
* version 2.1 of the License.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301 USA
*/
#include "private-libwebsockets.h"
#ifdef WIN32
#include <io.h>
#endif
int libwebsocket_client_rx_sm(struct libwebsocket *wsi, unsigned char c)
{
int n;
unsigned char buf[20 + 4];
int callback_action = LWS_CALLBACK_CLIENT_RECEIVE;
int handled;
struct lws_tokens eff_buf;
int m;
// lwsl_parser(" CRX: %02X %d\n", c, wsi->lws_rx_parse_state);
switch (wsi->lws_rx_parse_state) {
case LWS_RXPS_NEW:
switch (wsi->ietf_spec_revision) {
/* Firefox 4.0b6 likes this as of 30 Oct */
case 0:
if (c == 0xff)
wsi->lws_rx_parse_state = LWS_RXPS_SEEN_76_FF;
if (c == 0) {
wsi->lws_rx_parse_state =
LWS_RXPS_EAT_UNTIL_76_FF;
wsi->rx_user_buffer_head = 0;
}
break;
case 4:
case 5:
case 6:
case 7:
case 8:
case 13:
/*
* 04 logical framing from the spec (all this is masked when
* incoming and has to be unmasked)
*
* We ignore the possibility of extension data because we don't
* negotiate any extensions at the moment.
*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-------+-+-------------+-------------------------------+
* |F|R|R|R| opcode|R| Payload len | Extended payload length |
* |I|S|S|S| (4) |S| (7) | (16/63) |
* |N|V|V|V| |V| | (if payload len==126/127) |
* | |1|2|3| |4| | |
* +-+-+-+-+-------+-+-------------+ - - - - - - - - - - - - - - - +
* | Extended payload length continued, if payload len == 127 |
* + - - - - - - - - - - - - - - - +-------------------------------+
* | | Extension data |
* +-------------------------------+ - - - - - - - - - - - - - - - +
* : :
* +---------------------------------------------------------------+
* : Application data :
* +---------------------------------------------------------------+
*
* We pass payload through to userland as soon as we get it, ignoring
* FIN. It's up to userland to buffer it up if it wants to see a
* whole unfragmented block of the original size (which may be up to
* 2^63 long!)
*
* Notice in v7 RSV4 is set to indicate 32-bit frame key is coming in
* after length, unlike extension data which is now deprecated, this
* does not impact the payload length calculation.
*/
/*
* 04 spec defines the opcode like this: (1, 2, and 3 are
* "control frame" opcodes which may not be fragmented or
* have size larger than 126)
*
* frame-opcode =
* %x0 ; continuation frame
* / %x1 ; connection close
* / %x2 ; ping
* / %x3 ; pong
* / %x4 ; text frame
* / %x5 ; binary frame
* / %x6-F ; reserved
*
* FIN (b7)
*/
if (wsi->ietf_spec_revision < 7)
switch (c & 0xf) {
case LWS_WS_OPCODE_04__CONTINUATION:
wsi->opcode =
LWS_WS_OPCODE_07__CONTINUATION;
break;
case LWS_WS_OPCODE_04__CLOSE:
wsi->opcode = LWS_WS_OPCODE_07__CLOSE;
break;
case LWS_WS_OPCODE_04__PING:
wsi->opcode = LWS_WS_OPCODE_07__PING;
break;
case LWS_WS_OPCODE_04__PONG:
wsi->opcode = LWS_WS_OPCODE_07__PONG;
break;
case LWS_WS_OPCODE_04__TEXT_FRAME:
wsi->opcode =
LWS_WS_OPCODE_07__TEXT_FRAME;
break;
case LWS_WS_OPCODE_04__BINARY_FRAME:
wsi->opcode =
LWS_WS_OPCODE_07__BINARY_FRAME;
break;
default:
lwsl_warn("reserved opcodes not "
"usable pre v7 protocol\n");
return -1;
}
else
wsi->opcode = c & 0xf;
wsi->rsv = (c & 0x70);
wsi->final = !!((c >> 7) & 1);
wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN;
break;
default:
lwsl_err("client_rx_sm doesn't know how "
"to handle spec version %02d\n",
wsi->ietf_spec_revision);
break;
}
break;
case LWS_RXPS_04_FRAME_HDR_LEN:
if ((c & 0x80) && wsi->ietf_spec_revision < 7) {
lwsl_warn("Frame has extensions set illegally 4\n");
/* kill the connection */
return -1;
}
wsi->this_frame_masked = !!(c & 0x80);
switch (c & 0x7f) {
case 126:
/* control frames are not allowed to have big lengths */
if (wsi->opcode & 8)
goto illegal_ctl_length;
wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN16_2;
break;
case 127:
/* control frames are not allowed to have big lengths */
if (wsi->opcode & 8)
goto illegal_ctl_length;
wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN64_8;
break;
default:
wsi->rx_packet_length = c;
if (wsi->this_frame_masked)
wsi->lws_rx_parse_state =
LWS_RXPS_07_COLLECT_FRAME_KEY_1;
else {
if (c)
wsi->lws_rx_parse_state =
LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED;
else {
wsi->lws_rx_parse_state = LWS_RXPS_NEW;
goto spill;
}
}
break;
}
break;
case LWS_RXPS_04_FRAME_HDR_LEN16_2:
wsi->rx_packet_length = c << 8;
wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN16_1;
break;
case LWS_RXPS_04_FRAME_HDR_LEN16_1:
wsi->rx_packet_length |= c;
if (wsi->this_frame_masked)
wsi->lws_rx_parse_state =
LWS_RXPS_07_COLLECT_FRAME_KEY_1;
else {
if (wsi->rx_packet_length)
wsi->lws_rx_parse_state =
LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED;
else {
wsi->lws_rx_parse_state = LWS_RXPS_NEW;
goto spill;
}
}
break;
case LWS_RXPS_04_FRAME_HDR_LEN64_8:
if (c & 0x80) {
lwsl_warn("b63 of length must be zero\n");
/* kill the connection */
return -1;
}
#if defined __LP64__
wsi->rx_packet_length = ((size_t)c) << 56;
#else
wsi->rx_packet_length = 0;
#endif
wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN64_7;
break;
case LWS_RXPS_04_FRAME_HDR_LEN64_7:
#if defined __LP64__
wsi->rx_packet_length |= ((size_t)c) << 48;
#endif
wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN64_6;
break;
case LWS_RXPS_04_FRAME_HDR_LEN64_6:
#if defined __LP64__
wsi->rx_packet_length |= ((size_t)c) << 40;
#endif
wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN64_5;
break;
case LWS_RXPS_04_FRAME_HDR_LEN64_5:
#if defined __LP64__
wsi->rx_packet_length |= ((size_t)c) << 32;
#endif
wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN64_4;
break;
case LWS_RXPS_04_FRAME_HDR_LEN64_4:
wsi->rx_packet_length |= ((size_t)c) << 24;
wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN64_3;
break;
case LWS_RXPS_04_FRAME_HDR_LEN64_3:
wsi->rx_packet_length |= ((size_t)c) << 16;
wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN64_2;
break;
case LWS_RXPS_04_FRAME_HDR_LEN64_2:
wsi->rx_packet_length |= ((size_t)c) << 8;
wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN64_1;
break;
case LWS_RXPS_04_FRAME_HDR_LEN64_1:
wsi->rx_packet_length |= (size_t)c;
if (wsi->this_frame_masked)
wsi->lws_rx_parse_state =
LWS_RXPS_07_COLLECT_FRAME_KEY_1;
else {
if (wsi->rx_packet_length)
wsi->lws_rx_parse_state =
LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED;
else {
wsi->lws_rx_parse_state = LWS_RXPS_NEW;
goto spill;
}
}
break;
case LWS_RXPS_07_COLLECT_FRAME_KEY_1:
wsi->frame_masking_nonce_04[0] = c;
if (c)
wsi->all_zero_nonce = 0;
wsi->lws_rx_parse_state = LWS_RXPS_07_COLLECT_FRAME_KEY_2;
break;
case LWS_RXPS_07_COLLECT_FRAME_KEY_2:
wsi->frame_masking_nonce_04[1] = c;
if (c)
wsi->all_zero_nonce = 0;
wsi->lws_rx_parse_state = LWS_RXPS_07_COLLECT_FRAME_KEY_3;
break;
case LWS_RXPS_07_COLLECT_FRAME_KEY_3:
wsi->frame_masking_nonce_04[2] = c;
if (c)
wsi->all_zero_nonce = 0;
wsi->lws_rx_parse_state = LWS_RXPS_07_COLLECT_FRAME_KEY_4;
break;
case LWS_RXPS_07_COLLECT_FRAME_KEY_4:
wsi->frame_masking_nonce_04[3] = c;
if (c)
wsi->all_zero_nonce = 0;
if (wsi->rx_packet_length)
wsi->lws_rx_parse_state =
LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED;
else {
wsi->lws_rx_parse_state = LWS_RXPS_NEW;
goto spill;
}
break;
case LWS_RXPS_EAT_UNTIL_76_FF:
if (c == 0xff) {
wsi->lws_rx_parse_state = LWS_RXPS_NEW;
goto issue;
}
wsi->rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING +
(wsi->rx_user_buffer_head++)] = c;
if (wsi->rx_user_buffer_head != MAX_USER_RX_BUFFER)
break;
issue:
if (wsi->protocol->callback)
wsi->protocol->callback(wsi->protocol->owning_server,
wsi,
LWS_CALLBACK_CLIENT_RECEIVE,
wsi->user_space,
&wsi->rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING],
wsi->rx_user_buffer_head);
wsi->rx_user_buffer_head = 0;
break;
case LWS_RXPS_SEEN_76_FF:
if (c)
break;
lwsl_parser("Seen that client is requesting "
"a v76 close, sending ack\n");
buf[0] = 0xff;
buf[1] = 0;
n = libwebsocket_write(wsi, buf, 2, LWS_WRITE_HTTP);
if (n < 0) {
lwsl_warn("LWS_RXPS_SEEN_76_FF: ERROR writing to socket\n");
return -1;
}
lwsl_parser(" v76 close ack sent, server closing skt\n");
/* returning < 0 will get it closed in parent */
return -1;
case LWS_RXPS_PULLING_76_LENGTH:
break;
case LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED:
if ((!wsi->this_frame_masked) || wsi->all_zero_nonce)
wsi->rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING +
(wsi->rx_user_buffer_head++)] = c;
else
wsi->rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING +
(wsi->rx_user_buffer_head++)] =
wsi->xor_mask(wsi, c);
if (--wsi->rx_packet_length == 0) {
wsi->lws_rx_parse_state = LWS_RXPS_NEW;
goto spill;
}
if (wsi->rx_user_buffer_head != MAX_USER_RX_BUFFER)
break;
spill:
handled = 0;
/*
* is this frame a control packet we should take care of at this
* layer? If so service it and hide it from the user callback
*/
switch (wsi->opcode) {
case LWS_WS_OPCODE_07__CLOSE:
/* is this an acknowledgement of our close? */
if (wsi->state == WSI_STATE_AWAITING_CLOSE_ACK) {
/*
* fine he has told us he is closing too, let's
* finish our close
*/
lwsl_parser("seen server's close ack\n");
return -1;
}
lwsl_parser("client sees server close packet len = %d\n", wsi->rx_user_buffer_head);
/* parrot the close packet payload back */
n = libwebsocket_write(wsi, (unsigned char *)
&wsi->rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING],
wsi->rx_user_buffer_head, LWS_WRITE_CLOSE);
lwsl_parser("client writing close ack returned %d\n", n);
wsi->state = WSI_STATE_RETURNED_CLOSE_ALREADY;
/* close the connection */
return -1;
case LWS_WS_OPCODE_07__PING:
lwsl_info("client received ping, doing pong\n");
/* parrot the ping packet payload back as a pong*/
n = libwebsocket_write(wsi, (unsigned char *)
&wsi->rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING],
wsi->rx_user_buffer_head, LWS_WRITE_PONG);
handled = 1;
break;
case LWS_WS_OPCODE_07__PONG:
lwsl_info("client receied pong\n");
lwsl_hexdump(&wsi->rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING],
wsi->rx_user_buffer_head);
/* keep the statistics... */
wsi->pings_vs_pongs--;
/* issue it */
callback_action = LWS_CALLBACK_CLIENT_RECEIVE_PONG;
break;
case LWS_WS_OPCODE_07__CONTINUATION:
case LWS_WS_OPCODE_07__TEXT_FRAME:
case LWS_WS_OPCODE_07__BINARY_FRAME:
break;
default:
lwsl_parser("Reserved opcode 0x%2X\n", wsi->opcode);
/*
* It's something special we can't understand here.
* Pass the payload up to the extension's parsing
* state machine.
*/
eff_buf.token = &wsi->rx_user_buffer[
LWS_SEND_BUFFER_PRE_PADDING];
eff_buf.token_len = wsi->rx_user_buffer_head;
for (n = 0; n < wsi->count_active_extensions; n++) {
m = wsi->active_extensions[n]->callback(
wsi->protocol->owning_server,
wsi->active_extensions[n], wsi,
LWS_EXT_CALLBACK_EXTENDED_PAYLOAD_RX,
wsi->active_extensions_user[n],
&eff_buf, 0);
if (m)
handled = 1;
}
if (!handled) {
lwsl_ext("Unhandled extended opcode "
"0x%x - ignoring frame\n", wsi->opcode);
wsi->rx_user_buffer_head = 0;
return 0;
}
break;
}
/*
* No it's real payload, pass it up to the user callback.
* It's nicely buffered with the pre-padding taken care of
* so it can be sent straight out again using libwebsocket_write
*/
if (handled)
goto already_done;
eff_buf.token = &wsi->rx_user_buffer[
LWS_SEND_BUFFER_PRE_PADDING];
eff_buf.token_len = wsi->rx_user_buffer_head;
for (n = 0; n < wsi->count_active_extensions; n++) {
m = wsi->active_extensions[n]->callback(
wsi->protocol->owning_server,
wsi->active_extensions[n], wsi,
LWS_EXT_CALLBACK_PAYLOAD_RX,
wsi->active_extensions_user[n],
&eff_buf, 0);
if (m < 0) {
lwsl_ext(
"Extension '%s' failed to handle payload!\n",
wsi->active_extensions[n]->name);
return -1;
}
}
if (eff_buf.token_len > 0) {
eff_buf.token[eff_buf.token_len] = '\0';
if (wsi->protocol->callback) {
if (callback_action == LWS_CALLBACK_CLIENT_RECEIVE_PONG)
lwsl_info("Client doing pong callback\n");
wsi->protocol->callback(
wsi->protocol->owning_server,
wsi,
(enum libwebsocket_callback_reasons)callback_action,
wsi->user_space,
eff_buf.token,
eff_buf.token_len);
}
}
already_done:
wsi->rx_user_buffer_head = 0;
break;
default:
lwsl_err("client rx illegal state\n");
return 1;
}
return 0;
illegal_ctl_length:
lwsl_warn("Control frame asking for "
"extended length is illegal\n");
/* kill the connection */
return -1;
}
Reference in a new issue View git blame Copy permalink