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libwebsockets/lib/parsers.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

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/*
* libwebsockets - small server side websockets and web server implementation
*
* Copyright (C) 2010 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
static const struct lws_tokens lws_tokens[WSI_TOKEN_COUNT] = {
/* win32 can't do C99 */
/* [WSI_TOKEN_GET_URI] = */{ "GET ", 4 },
/* [WSI_TOKEN_HOST] = */{ "Host:", 5 },
/* [WSI_TOKEN_CONNECTION] = */{ "Connection:", 11 },
/* [WSI_TOKEN_KEY1] = */{ "Sec-WebSocket-Key1:", 19 },
/* [WSI_TOKEN_KEY2] = */{ "Sec-WebSocket-Key2:", 19 },
/* [WSI_TOKEN_PROTOCOL] = */{ "Sec-WebSocket-Protocol:", 23 },
/* [WSI_TOKEN_UPGRADE] = */{ "Upgrade:", 8 },
/* [WSI_TOKEN_ORIGIN] = */{ "Origin:", 7 },
/* [WSI_TOKEN_DRAFT] = */{ "Sec-WebSocket-Draft:", 20 },
/* [WSI_TOKEN_CHALLENGE] = */{ "\x0d\x0a", 2 },
/* [WSI_TOKEN_KEY] = */{ "Sec-WebSocket-Key:", 18 },
/* [WSI_TOKEN_VERSION] = */{ "Sec-WebSocket-Version:", 22 },
/* [WSI_TOKEN_SWORIGIN]= */{ "Sec-WebSocket-Origin:", 21 },
/* [WSI_TOKEN_EXTENSIONS] = */{ "Sec-WebSocket-Extensions:", 25 },
/* [WSI_TOKEN_ACCEPT] = */{ "Sec-WebSocket-Accept:", 21 },
/* [WSI_TOKEN_NONCE] = */{ "Sec-WebSocket-Nonce:", 20 },
/* [WSI_TOKEN_HTTP] = */{ "HTTP/1.1 ", 9 },
/* [WSI_TOKEN_MUXURL] = */{ "", -1 },
};
int libwebsocket_parse(struct libwebsocket *wsi, unsigned char c)
{
int n;
switch (wsi->parser_state) {
case WSI_TOKEN_GET_URI:
case WSI_TOKEN_HOST:
case WSI_TOKEN_CONNECTION:
case WSI_TOKEN_KEY1:
case WSI_TOKEN_KEY2:
case WSI_TOKEN_PROTOCOL:
case WSI_TOKEN_UPGRADE:
case WSI_TOKEN_ORIGIN:
case WSI_TOKEN_SWORIGIN:
case WSI_TOKEN_DRAFT:
case WSI_TOKEN_CHALLENGE:
case WSI_TOKEN_KEY:
case WSI_TOKEN_VERSION:
case WSI_TOKEN_ACCEPT:
case WSI_TOKEN_NONCE:
case WSI_TOKEN_EXTENSIONS:
case WSI_TOKEN_HTTP:
case WSI_TOKEN_MUXURL:
lwsl_parser("WSI_TOKEN_(%d) '%c'\n", wsi->parser_state, c);
/* collect into malloc'd buffers */
/* optional space swallow */
if (!wsi->utf8_token[wsi->parser_state].token_len && c == ' ')
break;
/* special case space terminator for get-uri */
if (wsi->parser_state == WSI_TOKEN_GET_URI && c == ' ') {
wsi->utf8_token[wsi->parser_state].token[
wsi->utf8_token[wsi->parser_state].token_len] = '\0';
// lwsl_parser("uri '%s'\n", wsi->utf8_token[wsi->parser_state].token);
wsi->parser_state = WSI_TOKEN_SKIPPING;
break;
}
/* allocate appropriate memory */
if (wsi->utf8_token[wsi->parser_state].token_len ==
wsi->current_alloc_len - 1) {
/* need to extend */
wsi->current_alloc_len += LWS_ADDITIONAL_HDR_ALLOC;
if (wsi->current_alloc_len >= LWS_MAX_HEADER_LEN) {
/* it's waaay to much payload, fail it */
strcpy(wsi->utf8_token[wsi->parser_state].token,
"!!! Length exceeded maximum supported !!!");
wsi->parser_state = WSI_TOKEN_SKIPPING;
break;
}
wsi->utf8_token[wsi->parser_state].token = (char *)
realloc(wsi->utf8_token[wsi->parser_state].token,
wsi->current_alloc_len);
if (wsi->utf8_token[wsi->parser_state].token == NULL) {
lwsl_err("Out of mem\n");
return -1;
}
}
/* bail at EOL */
if (wsi->parser_state != WSI_TOKEN_CHALLENGE && c == '\x0d') {
wsi->utf8_token[wsi->parser_state].token[
wsi->utf8_token[wsi->parser_state].token_len] = '\0';
wsi->parser_state = WSI_TOKEN_SKIPPING_SAW_CR;
lwsl_parser("*\n");
break;
}
wsi->utf8_token[wsi->parser_state].token[
wsi->utf8_token[wsi->parser_state].token_len++] = c;
/* per-protocol end of headers management */
if (wsi->parser_state != WSI_TOKEN_CHALLENGE)
break;
/* -76 has no version header ... server */
if (!wsi->utf8_token[WSI_TOKEN_VERSION].token_len &&
wsi->mode != LWS_CONNMODE_WS_CLIENT_WAITING_SERVER_REPLY &&
wsi->utf8_token[wsi->parser_state].token_len != 8)
break;
/* -76 has no version header ... client */
if (!wsi->utf8_token[WSI_TOKEN_VERSION].token_len &&
wsi->mode == LWS_CONNMODE_WS_CLIENT_WAITING_SERVER_REPLY &&
wsi->utf8_token[wsi->parser_state].token_len != 16)
break;
/* <= 03 has old handshake with version header needs 8 bytes */
if (wsi->utf8_token[WSI_TOKEN_VERSION].token_len &&
atoi(wsi->utf8_token[WSI_TOKEN_VERSION].token) < 4 &&
wsi->utf8_token[wsi->parser_state].token_len != 8)
break;
/* no payload challenge in 01 + */
if (wsi->utf8_token[WSI_TOKEN_VERSION].token_len &&
atoi(wsi->utf8_token[WSI_TOKEN_VERSION].token) > 0) {
wsi->utf8_token[WSI_TOKEN_CHALLENGE].token_len = 0;
free(wsi->utf8_token[WSI_TOKEN_CHALLENGE].token);
wsi->utf8_token[WSI_TOKEN_CHALLENGE].token = NULL;
}
/* For any supported protocol we have enough payload */
lwsl_parser("Setting WSI_PARSING_COMPLETE\n");
wsi->parser_state = WSI_PARSING_COMPLETE;
break;
case WSI_INIT_TOKEN_MUXURL:
wsi->parser_state = WSI_TOKEN_MUXURL;
wsi->current_alloc_len = LWS_INITIAL_HDR_ALLOC;
wsi->utf8_token[wsi->parser_state].token = (char *)
malloc(wsi->current_alloc_len);
if (wsi->utf8_token[wsi->parser_state].token == NULL) {
lwsl_err("Out of mem\n");
return -1;
}
wsi->utf8_token[wsi->parser_state].token_len = 0;
break;
/* collecting and checking a name part */
case WSI_TOKEN_NAME_PART:
lwsl_parser("WSI_TOKEN_NAME_PART '%c'\n", c);
if (wsi->name_buffer_pos == sizeof(wsi->name_buffer) - 1) {
/* name bigger than we can handle, skip until next */
wsi->parser_state = WSI_TOKEN_SKIPPING;
break;
}
wsi->name_buffer[wsi->name_buffer_pos++] = c;
wsi->name_buffer[wsi->name_buffer_pos] = '\0';
for (n = 0; n < WSI_TOKEN_COUNT; n++) {
if (wsi->name_buffer_pos != lws_tokens[n].token_len)
continue;
if (strcasecmp(lws_tokens[n].token, wsi->name_buffer))
continue;
lwsl_parser("known hdr '%s'\n", wsi->name_buffer);
/*
* WSORIGIN is protocol equiv to ORIGIN,
* JWebSocket likes to send it, map to ORIGIN
*/
if (n == WSI_TOKEN_SWORIGIN)
n = WSI_TOKEN_ORIGIN;
wsi->parser_state = (enum lws_token_indexes) (WSI_TOKEN_GET_URI + n);
n = WSI_TOKEN_COUNT;
/* If the header has been seen already, just append */
if (wsi->utf8_token[wsi->parser_state].token)
continue;
wsi->current_alloc_len = LWS_INITIAL_HDR_ALLOC;
wsi->utf8_token[wsi->parser_state].token = (char *)
malloc(wsi->current_alloc_len);
if (wsi->utf8_token[wsi->parser_state].token == NULL) {
lwsl_err("Out of mem\n");
return -1;
}
wsi->utf8_token[wsi->parser_state].token_len = 0;
}
/* colon delimiter means we just don't know this name */
if (wsi->parser_state == WSI_TOKEN_NAME_PART) {
if (c == ':') {
lwsl_parser("skipping unknown header '%s'\n",
wsi->name_buffer);
wsi->parser_state = WSI_TOKEN_SKIPPING;
break;
}
if (c == ' ' &&
!wsi->utf8_token[WSI_TOKEN_GET_URI].token_len) {
lwsl_parser("unknown method '%s'\n",
wsi->name_buffer);
wsi->parser_state = WSI_TOKEN_GET_URI;
wsi->current_alloc_len = LWS_INITIAL_HDR_ALLOC;
wsi->utf8_token[WSI_TOKEN_GET_URI].token =
(char *)malloc(wsi->current_alloc_len);
if (wsi->utf8_token[WSI_TOKEN_GET_URI].token == NULL) {
lwsl_err("Out of mem\n");
return -1;
}
break;
}
}
if (wsi->parser_state != WSI_TOKEN_CHALLENGE)
break;
/* don't look for payload when it can just be http headers */
if (!wsi->utf8_token[WSI_TOKEN_UPGRADE].token_len) {
/* they're HTTP headers, not websocket upgrade! */
lwsl_parser("Setting WSI_PARSING_COMPLETE "
"from http headers\n");
wsi->parser_state = WSI_PARSING_COMPLETE;
}
/* 04 version has no packet content after end of hdrs */
if (wsi->utf8_token[WSI_TOKEN_VERSION].token_len &&
atoi(wsi->utf8_token[WSI_TOKEN_VERSION].token) >= 4) {
lwsl_parser("04 header completed\n");
wsi->parser_state = WSI_PARSING_COMPLETE;
wsi->utf8_token[WSI_TOKEN_CHALLENGE].token_len = 0;
free(wsi->utf8_token[WSI_TOKEN_CHALLENGE].token);
wsi->utf8_token[WSI_TOKEN_CHALLENGE].token = NULL;
}
/* client parser? */
if (wsi->ietf_spec_revision >= 4) {
lwsl_parser("04 header completed\n");
wsi->parser_state = WSI_PARSING_COMPLETE;
}
break;
/* skipping arg part of a name we didn't recognize */
case WSI_TOKEN_SKIPPING:
lwsl_parser("WSI_TOKEN_SKIPPING '%c'\n", c);
if (c == '\x0d')
wsi->parser_state = WSI_TOKEN_SKIPPING_SAW_CR;
break;
case WSI_TOKEN_SKIPPING_SAW_CR:
lwsl_parser("WSI_TOKEN_SKIPPING_SAW_CR '%c'\n", c);
if (c == '\x0a')
wsi->parser_state = WSI_TOKEN_NAME_PART;
else
wsi->parser_state = WSI_TOKEN_SKIPPING;
wsi->name_buffer_pos = 0;
break;
/* we're done, ignore anything else */
case WSI_PARSING_COMPLETE:
lwsl_parser("WSI_PARSING_COMPLETE '%c'\n", c);
break;
default: /* keep gcc happy */
break;
}
return 0;
}
unsigned char
xor_no_mask(struct libwebsocket *wsi, unsigned char c)
{
return c;
}
unsigned char
xor_mask_04(struct libwebsocket *wsi, unsigned char c)
{
c ^= wsi->masking_key_04[wsi->frame_mask_index++];
if (wsi->frame_mask_index == 20)
wsi->frame_mask_index = 0;
return c;
}
unsigned char
xor_mask_05(struct libwebsocket *wsi, unsigned char c)
{
return c ^ wsi->frame_masking_nonce_04[(wsi->frame_mask_index++) & 3];
}
int
libwebsocket_rx_sm(struct libwebsocket *wsi, unsigned char c)
{
int n;
unsigned char buf[20 + 4];
struct lws_tokens eff_buf;
int handled;
int m;
#if 0
lwsl_debug("RX: %02X ", c);
#endif
switch (wsi->lws_rx_parse_state) {
case LWS_RXPS_NEW:
switch (wsi->ietf_spec_revision) {
/* Firefox 4.0b6 likes this as of 30 Oct 2010 */
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:
wsi->all_zero_nonce = 1;
wsi->frame_masking_nonce_04[0] = c;
if (c)
wsi->all_zero_nonce = 0;
wsi->lws_rx_parse_state = LWS_RXPS_04_MASK_NONCE_1;
break;
case 7:
case 8:
case 13:
/*
* no prepended frame key any more
*/
wsi->all_zero_nonce = 1;
goto handle_first;
default:
lwsl_warn("libwebsocket_rx_sm doesn't know "
"about spec version %d\n", wsi->ietf_spec_revision);
break;
}
break;
case LWS_RXPS_04_MASK_NONCE_1:
wsi->frame_masking_nonce_04[1] = c;
if (c)
wsi->all_zero_nonce = 0;
wsi->lws_rx_parse_state = LWS_RXPS_04_MASK_NONCE_2;
break;
case LWS_RXPS_04_MASK_NONCE_2:
wsi->frame_masking_nonce_04[2] = c;
if (c)
wsi->all_zero_nonce = 0;
wsi->lws_rx_parse_state = LWS_RXPS_04_MASK_NONCE_3;
break;
case LWS_RXPS_04_MASK_NONCE_3:
wsi->frame_masking_nonce_04[3] = c;
if (c)
wsi->all_zero_nonce = 0;
if (wsi->protocol->owning_server->options &
LWS_SERVER_OPTION_DEFEAT_CLIENT_MASK)
goto post_mask;
if (wsi->ietf_spec_revision > 4)
goto post_sha1;
/*
* we are able to compute the frame key now
* it's a SHA1 of ( frame nonce we were just sent, concatenated
* with the connection masking key we computed at handshake
* time ) -- yeah every frame from the client invokes a SHA1
* for no real reason so much for lightweight.
*/
buf[0] = wsi->frame_masking_nonce_04[0];
buf[1] = wsi->frame_masking_nonce_04[1];
buf[2] = wsi->frame_masking_nonce_04[2];
buf[3] = wsi->frame_masking_nonce_04[3];
memcpy(buf + 4, wsi->masking_key_04, 20);
/*
* wsi->frame_mask_04 will be our recirculating 20-byte XOR key
* for this frame
*/
SHA1((unsigned char *)buf, 4 + 20, wsi->frame_mask_04);
post_sha1:
/*
* start from the zero'th byte in the XOR key buffer since
* this is the start of a frame with a new key
*/
wsi->frame_mask_index = 0;
post_mask:
wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_1;
break;
/*
* 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!)
*/
case LWS_RXPS_04_FRAME_HDR_1:
handle_first:
/*
* 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)
c = wsi->xor_mask(wsi, c);
/* translate all incoming opcodes into v7+ map */
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;
case LWS_RXPS_04_FRAME_HDR_LEN:
if (wsi->ietf_spec_revision < 7)
c = wsi->xor_mask(wsi, c);
if ((c & 0x80) && wsi->ietf_spec_revision < 7) {
lwsl_warn("Frame has extensions set illegally 2\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 & 0x7f;
if (wsi->this_frame_masked)
wsi->lws_rx_parse_state =
LWS_RXPS_07_COLLECT_FRAME_KEY_1;
else
wsi->lws_rx_parse_state =
LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED;
break;
}
break;
case LWS_RXPS_04_FRAME_HDR_LEN16_2:
if (wsi->ietf_spec_revision < 7)
c = wsi->xor_mask(wsi, c);
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:
if (wsi->ietf_spec_revision < 7)
c = wsi->xor_mask(wsi, c);
wsi->rx_packet_length |= c;
if (wsi->this_frame_masked)
wsi->lws_rx_parse_state =
LWS_RXPS_07_COLLECT_FRAME_KEY_1;
else
wsi->lws_rx_parse_state =
LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED;
break;
case LWS_RXPS_04_FRAME_HDR_LEN64_8:
if (wsi->ietf_spec_revision < 7)
c = wsi->xor_mask(wsi, c);
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 (wsi->ietf_spec_revision < 7)
c = wsi->xor_mask(wsi, c);
#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 (wsi->ietf_spec_revision < 7)
c = wsi->xor_mask(wsi, c);
#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 (wsi->ietf_spec_revision < 7)
c = wsi->xor_mask(wsi, c);
#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:
if (wsi->ietf_spec_revision < 7)
c = wsi->xor_mask(wsi, c);
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:
if (wsi->ietf_spec_revision < 7)
c = wsi->xor_mask(wsi, c);
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:
if (wsi->ietf_spec_revision < 7)
c = wsi->xor_mask(wsi, c);
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:
if (wsi->ietf_spec_revision < 7)
c = wsi->xor_mask(wsi, c);
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
wsi->lws_rx_parse_state =
LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED;
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_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("ERROR writing to socket");
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_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;
wsi->lws_rx_parse_state =
LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED;
wsi->frame_mask_index = 0;
break;
case LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED:
if (wsi->ietf_spec_revision < 4 ||
(wsi->all_zero_nonce && wsi->ietf_spec_revision >= 5))
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:
/*
* 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
*/
lwsl_parser("spill on %s\n", wsi->protocol->name);
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 client close ack\n");
return -1;
}
lwsl_parser("server sees client close packet\n");
/* 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);
wsi->state = WSI_STATE_RETURNED_CLOSE_ALREADY;
/* close the connection */
return -1;
case LWS_WS_OPCODE_07__PING:
lwsl_info("received %d byte ping, sending pong\n", wsi->rx_user_buffer_head);
lwsl_hexdump(&wsi->rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING], wsi->rx_user_buffer_head);
/* 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);
/* ... then just drop it */
wsi->rx_user_buffer_head = 0;
return 0;
case LWS_WS_OPCODE_07__PONG:
/* keep the statistics... */
wsi->pings_vs_pongs--;
/* ... then just drop it */
wsi->rx_user_buffer_head = 0;
return 0;
case LWS_WS_OPCODE_07__CONTINUATION:
case LWS_WS_OPCODE_07__TEXT_FRAME:
case LWS_WS_OPCODE_07__BINARY_FRAME:
break;
default:
lwsl_parser("passing opcode %x up to exts\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;
handled = 0;
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;
}
/*
* 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
*/
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)
wsi->protocol->callback(wsi->protocol->owning_server,
wsi, LWS_CALLBACK_RECEIVE,
wsi->user_space,
eff_buf.token,
eff_buf.token_len);
else
lwsl_err("No callback on payload spill!\n");
}
wsi->rx_user_buffer_head = 0;
break;
}
return 0;
illegal_ctl_length:
lwsl_warn("Control frame asking for "
"extended length is illegal\n");
/* kill the connection */
return -1;
}
int libwebsocket_interpret_incoming_packet(struct libwebsocket *wsi,
unsigned char *buf, size_t len)
{
size_t n;
#ifdef DEBUG
lwsl_parser("received %d byte packet\n", (int)len);
for (n = 0; n < len; n++)
lwsl_parser("%02X ", buf[n]);
lwsl_parser("\n");
#endif
/* let the rx protocol state machine have as much as it needs */
n = 0;
while (n < len)
if (libwebsocket_rx_sm(wsi, buf[n++]) < 0)
return -1;
return 0;
}
/**
* libwebsockets_remaining_packet_payload() - Bytes to come before "overall"
* rx packet is complete
* @wsi: Websocket instance (available from user callback)
*
* This function is intended to be called from the callback if the
* user code is interested in "complete packets" from the client.
* libwebsockets just passes through payload as it comes and issues a buffer
* additionally when it hits a built-in limit. The LWS_CALLBACK_RECEIVE
* callback handler can use this API to find out if the buffer it has just
* been given is the last piece of a "complete packet" from the client --
* when that is the case libwebsockets_remaining_packet_payload() will return
* 0.
*
* Many protocols won't care becuse their packets are always small.
*/
size_t
libwebsockets_remaining_packet_payload(struct libwebsocket *wsi)
{
return wsi->rx_packet_length;
}
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