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libwebsockets/lib/parsers.c
Andy Green 566eb4381c introduce lws_hdr_copy_fragment 
This adds a public API variant of the header copy api that lets you
choose which fragment you want copied.

Normally you want the existing one that aggregates the fragments.

But it can be useful to get each part in turn (that corresponds to
the content provided by each duplicated header normally).

Signed-off-by: Andy Green <andy.green@linaro.org>
2015-12-15 22:59:23 +08:00

1056 lines
27 KiB
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/*
* 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"
unsigned char lextable[] = {
#include "lextable.h"
};
#define FAIL_CHAR 0x08
int lextable_decode(int pos, char c)
{
c = tolower(c);
while (1) {
if (lextable[pos] & (1 << 7)) { /* 1-byte, fail on mismatch */
if ((lextable[pos] & 0x7f) != c)
return -1;
/* fall thru */
pos++;
if (lextable[pos] == FAIL_CHAR)
return -1;
return pos;
}
if (lextable[pos] == FAIL_CHAR)
return -1;
/* b7 = 0, end or 3-byte */
if (lextable[pos] < FAIL_CHAR) /* terminal marker */
return pos;
if (lextable[pos] == c) /* goto */
return pos + (lextable[pos + 1]) +
(lextable[pos + 2] << 8);
/* fall thru goto */
pos += 3;
/* continue */
}
}
int lws_allocate_header_table(struct lws *wsi)
{
/* Be sure to free any existing header data to avoid mem leak: */
lws_free_header_table(wsi);
wsi->u.hdr.ah = lws_malloc(sizeof(*wsi->u.hdr.ah));
if (wsi->u.hdr.ah == NULL) {
lwsl_err("Out of memory\n");
return -1;
}
memset(wsi->u.hdr.ah->frag_index, 0, sizeof(wsi->u.hdr.ah->frag_index));
wsi->u.hdr.ah->nfrag = 0;
wsi->u.hdr.ah->pos = 0;
return 0;
}
int lws_free_header_table(struct lws *wsi)
{
lws_free2(wsi->u.hdr.ah);
wsi->u.hdr.ah = NULL;
return 0;
};
LWS_VISIBLE int lws_hdr_total_length(struct lws *wsi, enum lws_token_indexes h)
{
int n;
int len = 0;
n = wsi->u.hdr.ah->frag_index[h];
if (!n)
return 0;
do {
len += wsi->u.hdr.ah->frags[n].len;
n = wsi->u.hdr.ah->frags[n].nfrag;
} while (n);
return len;
}
LWS_VISIBLE int lws_hdr_copy_fragment(struct lws *wsi, char *dst, int len,
enum lws_token_indexes h, int frag_idx)
{
int n = 0;
int f = wsi->u.hdr.ah->frag_index[h];
while (n < frag_idx) {
f = wsi->u.hdr.ah->frags[f].nfrag;
if (!f)
return -1;
n++;
}
if (wsi->u.hdr.ah->frags[f].len >= (len - 1))
return -1;
memcpy(dst, &wsi->u.hdr.ah->data[wsi->u.hdr.ah->frags[f].offset],
wsi->u.hdr.ah->frags[f].len);
dst[wsi->u.hdr.ah->frags[f].len] = '\0';
return wsi->u.hdr.ah->frags[f].len;
}
LWS_VISIBLE int lws_hdr_copy(struct lws *wsi, char *dst, int len,
enum lws_token_indexes h)
{
int toklen = lws_hdr_total_length(wsi, h);
int n;
if (toklen >= len)
return -1;
n = wsi->u.hdr.ah->frag_index[h];
if (!n)
return 0;
do {
strcpy(dst, &wsi->u.hdr.ah->data[wsi->u.hdr.ah->frags[n].offset]);
dst += wsi->u.hdr.ah->frags[n].len;
n = wsi->u.hdr.ah->frags[n].nfrag;
} while (n);
return toklen;
}
char *lws_hdr_simple_ptr(struct lws *wsi, enum lws_token_indexes h)
{
int n;
n = wsi->u.hdr.ah->frag_index[h];
if (!n)
return NULL;
return &wsi->u.hdr.ah->data[wsi->u.hdr.ah->frags[n].offset];
}
int lws_hdr_simple_create(struct lws *wsi, enum lws_token_indexes h,
const char *s)
{
wsi->u.hdr.ah->nfrag++;
if (wsi->u.hdr.ah->nfrag == ARRAY_SIZE(wsi->u.hdr.ah->frags)) {
lwsl_warn("More hdr frags than we can deal with, dropping\n");
return -1;
}
wsi->u.hdr.ah->frag_index[h] = wsi->u.hdr.ah->nfrag;
wsi->u.hdr.ah->frags[wsi->u.hdr.ah->nfrag].offset = wsi->u.hdr.ah->pos;
wsi->u.hdr.ah->frags[wsi->u.hdr.ah->nfrag].len = 0;
wsi->u.hdr.ah->frags[wsi->u.hdr.ah->nfrag].nfrag = 0;
do {
if (wsi->u.hdr.ah->pos == sizeof(wsi->u.hdr.ah->data)) {
lwsl_err("Ran out of header data space\n");
return -1;
}
wsi->u.hdr.ah->data[wsi->u.hdr.ah->pos++] = *s;
if (*s)
wsi->u.hdr.ah->frags[wsi->u.hdr.ah->nfrag].len++;
} while (*s++);
return 0;
}
static signed char char_to_hex(const char c)
{
if (c >= '0' && c <= '9')
return c - '0';
if (c >= 'a' && c <= 'f')
return c - 'a' + 10;
if (c >= 'A' && c <= 'F')
return c - 'A' + 10;
return -1;
}
static int issue_char(struct lws *wsi, unsigned char c)
{
unsigned short frag_len;
if (wsi->u.hdr.ah->pos == sizeof(wsi->u.hdr.ah->data)) {
lwsl_warn("excessive header content\n");
return -1;
}
frag_len = wsi->u.hdr.ah->frags[wsi->u.hdr.ah->nfrag].len;
/*
* If we haven't hit the token limit, just copy the character into
* the header
*/
if (frag_len < wsi->u.hdr.current_token_limit) {
wsi->u.hdr.ah->data[wsi->u.hdr.ah->pos++] = c;
if (c)
wsi->u.hdr.ah->frags[wsi->u.hdr.ah->nfrag].len++;
return 0;
}
/* Insert a null character when we *hit* the limit: */
if (frag_len == wsi->u.hdr.current_token_limit) {
wsi->u.hdr.ah->data[wsi->u.hdr.ah->pos++] = '\0';
lwsl_warn("header %i exceeds limit\n",
wsi->u.hdr.parser_state);
}
return 1;
}
int lws_parse(struct lws *wsi, unsigned char c)
{
static const unsigned char methods[] = {
WSI_TOKEN_GET_URI,
WSI_TOKEN_POST_URI,
WSI_TOKEN_OPTIONS_URI,
WSI_TOKEN_PUT_URI,
WSI_TOKEN_PATCH_URI,
WSI_TOKEN_DELETE_URI,
};
struct allocated_headers *ah = wsi->u.hdr.ah;
struct lws_context *context = wsi->context;
unsigned int n, m, enc = 0;
switch (wsi->u.hdr.parser_state) {
default:
lwsl_parser("WSI_TOK_(%d) '%c'\n", wsi->u.hdr.parser_state, c);
/* collect into malloc'd buffers */
/* optional initial space swallow */
if (!ah->frags[ah->frag_index[
wsi->u.hdr.parser_state]].len && c == ' ')
break;
for (m = 0; m < ARRAY_SIZE(methods); m++)
if (wsi->u.hdr.parser_state == methods[m])
break;
if (m == ARRAY_SIZE(methods))
/* it was not any of the methods */
goto check_eol;
/* special URI processing... end at space */
if (c == ' ') {
/* enforce starting with / */
if (!ah->frags[ah->nfrag].len)
if (issue_char(wsi, '/') < 0)
return -1;
/* begin parsing HTTP version: */
if (issue_char(wsi, '\0') < 0)
return -1;
wsi->u.hdr.parser_state = WSI_TOKEN_HTTP;
goto start_fragment;
}
/* special URI processing... convert %xx */
switch (wsi->u.hdr.ues) {
case URIES_IDLE:
if (c == '%') {
wsi->u.hdr.ues = URIES_SEEN_PERCENT;
goto swallow;
}
break;
case URIES_SEEN_PERCENT:
if (char_to_hex(c) < 0) {
/* regurgitate */
if (issue_char(wsi, '%') < 0)
return -1;
wsi->u.hdr.ues = URIES_IDLE;
/* continue on to assess c */
break;
}
wsi->u.hdr.esc_stash = c;
wsi->u.hdr.ues = URIES_SEEN_PERCENT_H1;
goto swallow;
case URIES_SEEN_PERCENT_H1:
if (char_to_hex(c) < 0) {
/* regurgitate */
issue_char(wsi, '%');
wsi->u.hdr.ues = URIES_IDLE;
/* regurgitate + assess */
if (lws_parse(wsi, wsi->u.hdr.esc_stash) < 0)
return -1;
/* continue on to assess c */
break;
}
c = (char_to_hex(wsi->u.hdr.esc_stash) << 4) |
char_to_hex(c);
enc = 1;
wsi->u.hdr.ues = URIES_IDLE;
break;
}
/*
* special URI processing...
* convert /.. or /... or /../ etc to /
* convert /./ to /
* convert // or /// etc to /
* leave /.dir or whatever alone
*/
switch (wsi->u.hdr.ups) {
case URIPS_IDLE:
/* issue the first / always */
if (c == '/')
wsi->u.hdr.ups = URIPS_SEEN_SLASH;
break;
case URIPS_SEEN_SLASH:
/* swallow subsequent slashes */
if (c == '/')
goto swallow;
/* track and swallow the first . after / */
if (c == '.') {
wsi->u.hdr.ups = URIPS_SEEN_SLASH_DOT;
goto swallow;
}
wsi->u.hdr.ups = URIPS_IDLE;
break;
case URIPS_SEEN_SLASH_DOT:
/* swallow second . */
if (c == '.') {
/*
* back up one dir level if possible
* safe against header fragmentation because
* the method URI can only be in 1 fragment
*/
if (ah->frags[ah->nfrag].len > 2) {
ah->pos--;
ah->frags[ah->nfrag].len--;
do {
ah->pos--;
ah->frags[ah->nfrag].len--;
} while (ah->frags[ah->nfrag].len > 1 &&
ah->data[ah->pos] != '/');
}
wsi->u.hdr.ups = URIPS_SEEN_SLASH_DOT_DOT;
goto swallow;
}
/* change /./ to / */
if (c == '/') {
wsi->u.hdr.ups = URIPS_SEEN_SLASH;
goto swallow;
}
/* it was like /.dir ... regurgitate the . */
wsi->u.hdr.ups = URIPS_IDLE;
issue_char(wsi, '.');
break;
case URIPS_SEEN_SLASH_DOT_DOT:
/* swallow prior .. chars and any subsequent . */
if (c == '.')
goto swallow;
/* last issued was /, so another / == // */
if (c == '/')
goto swallow;
/* last we issued was / so SEEN_SLASH */
wsi->u.hdr.ups = URIPS_SEEN_SLASH;
break;
case URIPS_ARGUMENTS:
/* leave them alone */
break;
}
if (c == '?' && !enc) { /* start of URI arguments */
/* seal off uri header */
ah->data[ah->pos++] = '\0';
/* move to using WSI_TOKEN_HTTP_URI_ARGS */
ah->nfrag++;
ah->frags[ah->nfrag].offset = ah->pos;
ah->frags[ah->nfrag].len = 0;
ah->frags[ah->nfrag].nfrag = 0;
ah->frag_index[WSI_TOKEN_HTTP_URI_ARGS] = ah->nfrag;
/* defeat normal uri path processing */
wsi->u.hdr.ups = URIPS_ARGUMENTS;
goto swallow;
}
check_eol:
/* bail at EOL */
if (wsi->u.hdr.parser_state != WSI_TOKEN_CHALLENGE &&
c == '\x0d') {
c = '\0';
wsi->u.hdr.parser_state = WSI_TOKEN_SKIPPING_SAW_CR;
lwsl_parser("*\n");
}
n = issue_char(wsi, c);
if ((int)n < 0)
return -1;
if (n > 0)
wsi->u.hdr.parser_state = WSI_TOKEN_SKIPPING;
swallow:
/* per-protocol end of headers management */
if (wsi->u.hdr.parser_state == WSI_TOKEN_CHALLENGE)
goto set_parsing_complete;
break;
/* collecting and checking a name part */
case WSI_TOKEN_NAME_PART:
lwsl_parser("WSI_TOKEN_NAME_PART '%c' (mode=%d)\n", c, wsi->mode);
wsi->u.hdr.lextable_pos =
lextable_decode(wsi->u.hdr.lextable_pos, c);
/*
* Server needs to look out for unknown methods...
*/
if (wsi->u.hdr.lextable_pos < 0 &&
wsi->mode == LWS_CONNMODE_HTTP_SERVING) {
/* this is not a header we know about */
for (m = 0; m < ARRAY_SIZE(methods); m++)
if (ah->frag_index[methods[m]]) {
/*
* already had the method, no idea what
* this crap from the client is, ignore
*/
wsi->u.hdr.parser_state = WSI_TOKEN_SKIPPING;
break;
}
/*
* hm it's an unknown http method from a client in fact,
* treat as dangerous
*/
if (m == ARRAY_SIZE(methods)) {
lwsl_info("Unknown method - dropping\n");
return -1;
}
break;
}
/*
* ...otherwise for a client, let him ignore unknown headers
* coming from the server
*/
if (wsi->u.hdr.lextable_pos < 0) {
wsi->u.hdr.parser_state = WSI_TOKEN_SKIPPING;
break;
}
if (lextable[wsi->u.hdr.lextable_pos] < FAIL_CHAR) {
/* terminal state */
n = ((unsigned int)lextable[wsi->u.hdr.lextable_pos] << 8) |
lextable[wsi->u.hdr.lextable_pos + 1];
lwsl_parser("known hdr %d\n", n);
for (m = 0; m < ARRAY_SIZE(methods); m++)
if (n == methods[m] &&
ah->frag_index[
methods[m]]) {
lwsl_warn("Duplicated method\n");
return -1;
}
/*
* WSORIGIN is protocol equiv to ORIGIN,
* JWebSocket likes to send it, map to ORIGIN
*/
if (n == WSI_TOKEN_SWORIGIN)
n = WSI_TOKEN_ORIGIN;
wsi->u.hdr.parser_state = (enum lws_token_indexes)
(WSI_TOKEN_GET_URI + n);
if (context->token_limits)
wsi->u.hdr.current_token_limit =
context->token_limits->token_limit[
wsi->u.hdr.parser_state];
else
wsi->u.hdr.current_token_limit = sizeof(ah->data);
if (wsi->u.hdr.parser_state == WSI_TOKEN_CHALLENGE)
goto set_parsing_complete;
goto start_fragment;
}
break;
start_fragment:
ah->nfrag++;
if (ah->nfrag == ARRAY_SIZE(ah->frags)) {
lwsl_warn("More hdr frags than we can deal with\n");
return -1;
}
ah->frags[ah->nfrag].offset = ah->pos;
ah->frags[ah->nfrag].len = 0;
ah->frags[ ah->nfrag].nfrag = 0;
n = ah->frag_index[wsi->u.hdr.parser_state];
if (!n) { /* first fragment */
ah->frag_index[wsi->u.hdr.parser_state] = ah->nfrag;
break;
}
/* continuation */
while (ah->frags[n].nfrag)
n = ah->frags[n].nfrag;
ah->frags[n].nfrag = ah->nfrag;
if (ah->pos == sizeof(ah->data)) {
lwsl_warn("excessive header content\n");
return -1;
}
ah->data[ah->pos++] = ' ';
ah->frags[ah->nfrag].len++;
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->u.hdr.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->u.hdr.parser_state = WSI_TOKEN_NAME_PART;
wsi->u.hdr.lextable_pos = 0;
} else
wsi->u.hdr.parser_state = WSI_TOKEN_SKIPPING;
break;
/* we're done, ignore anything else */
case WSI_PARSING_COMPLETE:
lwsl_parser("WSI_PARSING_COMPLETE '%c'\n", c);
break;
}
return 0;
set_parsing_complete:
if (lws_hdr_total_length(wsi, WSI_TOKEN_UPGRADE)) {
if (lws_hdr_total_length(wsi, WSI_TOKEN_VERSION))
wsi->ietf_spec_revision =
atoi(lws_hdr_simple_ptr(wsi, WSI_TOKEN_VERSION));
lwsl_parser("v%02d hdrs completed\n", wsi->ietf_spec_revision);
}
wsi->u.hdr.parser_state = WSI_PARSING_COMPLETE;
wsi->hdr_parsing_completed = 1;
return 0;
}
/**
* lws_frame_is_binary: true if the current frame was sent in binary mode
*
* @wsi: the connection we are inquiring about
*
* This is intended to be called from the LWS_CALLBACK_RECEIVE callback if
* it's interested to see if the frame it's dealing with was sent in binary
* mode.
*/
LWS_VISIBLE int lws_frame_is_binary(struct lws *wsi)
{
return wsi->u.ws.frame_is_binary;
}
int
lws_rx_sm(struct lws *wsi, unsigned char c)
{
struct lws_tokens eff_buf;
int ret = 0;
int callback_action = LWS_CALLBACK_RECEIVE;
switch (wsi->lws_rx_parse_state) {
case LWS_RXPS_NEW:
switch (wsi->ietf_spec_revision) {
case 13:
/*
* no prepended frame key any more
*/
wsi->u.ws.all_zero_nonce = 1;
goto handle_first;
default:
lwsl_warn("lws_rx_sm: unknown spec version %d\n",
wsi->ietf_spec_revision);
break;
}
break;
case LWS_RXPS_04_MASK_NONCE_1:
wsi->u.ws.frame_masking_nonce_04[1] = c;
if (c)
wsi->u.ws.all_zero_nonce = 0;
wsi->lws_rx_parse_state = LWS_RXPS_04_MASK_NONCE_2;
break;
case LWS_RXPS_04_MASK_NONCE_2:
wsi->u.ws.frame_masking_nonce_04[2] = c;
if (c)
wsi->u.ws.all_zero_nonce = 0;
wsi->lws_rx_parse_state = LWS_RXPS_04_MASK_NONCE_3;
break;
case LWS_RXPS_04_MASK_NONCE_3:
wsi->u.ws.frame_masking_nonce_04[3] = c;
if (c)
wsi->u.ws.all_zero_nonce = 0;
/*
* start from the zero'th byte in the XOR key buffer since
* this is the start of a frame with a new key
*/
wsi->u.ws.frame_mask_index = 0;
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:
wsi->u.ws.opcode = c & 0xf;
wsi->u.ws.rsv = c & 0x70;
wsi->u.ws.final = !!((c >> 7) & 1);
switch (wsi->u.ws.opcode) {
case LWS_WS_OPCODE_07__TEXT_FRAME:
case LWS_WS_OPCODE_07__BINARY_FRAME:
wsi->u.ws.frame_is_binary =
wsi->u.ws.opcode == LWS_WS_OPCODE_07__BINARY_FRAME;
break;
}
wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN;
break;
case LWS_RXPS_04_FRAME_HDR_LEN:
wsi->u.ws.this_frame_masked = !!(c & 0x80);
switch (c & 0x7f) {
case 126:
/* control frames are not allowed to have big lengths */
if (wsi->u.ws.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->u.ws.opcode & 8)
goto illegal_ctl_length;
wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN64_8;
break;
default:
wsi->u.ws.rx_packet_length = c & 0x7f;
if (wsi->u.ws.this_frame_masked)
wsi->lws_rx_parse_state =
LWS_RXPS_07_COLLECT_FRAME_KEY_1;
else
if (wsi->u.ws.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;
}
break;
case LWS_RXPS_04_FRAME_HDR_LEN16_2:
wsi->u.ws.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->u.ws.rx_packet_length |= c;
if (wsi->u.ws.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 (c & 0x80) {
lwsl_warn("b63 of length must be zero\n");
/* kill the connection */
return -1;
}
#if defined __LP64__
wsi->u.ws.rx_packet_length = ((size_t)c) << 56;
#else
wsi->u.ws.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->u.ws.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->u.ws.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->u.ws.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->u.ws.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->u.ws.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->u.ws.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->u.ws.rx_packet_length |= ((size_t)c);
if (wsi->u.ws.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_07_COLLECT_FRAME_KEY_1:
wsi->u.ws.frame_masking_nonce_04[0] = c;
if (c)
wsi->u.ws.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->u.ws.frame_masking_nonce_04[1] = c;
if (c)
wsi->u.ws.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->u.ws.frame_masking_nonce_04[2] = c;
if (c)
wsi->u.ws.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->u.ws.frame_masking_nonce_04[3] = c;
if (c)
wsi->u.ws.all_zero_nonce = 0;
wsi->lws_rx_parse_state =
LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED;
wsi->u.ws.frame_mask_index = 0;
if (wsi->u.ws.rx_packet_length == 0) {
wsi->lws_rx_parse_state = LWS_RXPS_NEW;
goto spill;
}
break;
case LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED:
if (!wsi->u.ws.rx_user_buffer) {
lwsl_err("NULL user buffer...\n");
return 1;
}
if (wsi->u.ws.all_zero_nonce)
wsi->u.ws.rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING +
(wsi->u.ws.rx_user_buffer_head++)] = c;
else
wsi->u.ws.rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING +
(wsi->u.ws.rx_user_buffer_head++)] =
c ^ wsi->u.ws.frame_masking_nonce_04[
(wsi->u.ws.frame_mask_index++) & 3];
if (--wsi->u.ws.rx_packet_length == 0) {
/* spill because we have the whole frame */
wsi->lws_rx_parse_state = LWS_RXPS_NEW;
goto spill;
}
/*
* if there's no protocol max frame size given, we are
* supposed to default to LWS_MAX_SOCKET_IO_BUF
*/
if (!wsi->protocol->rx_buffer_size &&
wsi->u.ws.rx_user_buffer_head !=
LWS_MAX_SOCKET_IO_BUF)
break;
else
if (wsi->protocol->rx_buffer_size &&
wsi->u.ws.rx_user_buffer_head !=
wsi->protocol->rx_buffer_size)
break;
/* spill because we filled our rx buffer */
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->u.ws.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;
}
if (wsi->state == WSI_STATE_RETURNED_CLOSE_ALREADY)
/* if he sends us 2 CLOSE, kill him */
return -1;
lwsl_parser("server sees client close packet\n");
wsi->state = WSI_STATE_RETURNED_CLOSE_ALREADY;
/* deal with the close packet contents as a PONG */
wsi->u.ws.payload_is_close = 1;
goto process_as_ping;
case LWS_WS_OPCODE_07__PING:
lwsl_info("received %d byte ping, sending pong\n",
wsi->u.ws.rx_user_buffer_head);
if (wsi->u.ws.ping_pending_flag) {
/*
* there is already a pending ping payload
* we should just log and drop
*/
lwsl_parser("DROP PING since one pending\n");
goto ping_drop;
}
process_as_ping:
/* control packets can only be < 128 bytes long */
if (wsi->u.ws.rx_user_buffer_head > 128 - 4) {
lwsl_parser("DROP PING payload too large\n");
goto ping_drop;
}
/* if existing buffer is too small, drop it */
if (wsi->u.ws.ping_payload_buf &&
wsi->u.ws.ping_payload_alloc < wsi->u.ws.rx_user_buffer_head) {
lws_free2(wsi->u.ws.ping_payload_buf);
}
/* if no buffer, allocate it */
if (!wsi->u.ws.ping_payload_buf) {
wsi->u.ws.ping_payload_buf = lws_malloc(wsi->u.ws.rx_user_buffer_head
+ LWS_SEND_BUFFER_PRE_PADDING);
wsi->u.ws.ping_payload_alloc = wsi->u.ws.rx_user_buffer_head;
}
/* stash the pong payload */
memcpy(wsi->u.ws.ping_payload_buf + LWS_SEND_BUFFER_PRE_PADDING,
&wsi->u.ws.rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING],
wsi->u.ws.rx_user_buffer_head);
wsi->u.ws.ping_payload_len = wsi->u.ws.rx_user_buffer_head;
wsi->u.ws.ping_pending_flag = 1;
/* get it sent as soon as possible */
lws_callback_on_writable(lws_get_ctx(wsi), wsi);
ping_drop:
wsi->u.ws.rx_user_buffer_head = 0;
return 0;
case LWS_WS_OPCODE_07__PONG:
lwsl_info("received pong\n");
lwsl_hexdump(&wsi->u.ws.rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING],
wsi->u.ws.rx_user_buffer_head);
/* issue it */
callback_action = LWS_CALLBACK_RECEIVE_PONG;
break;
case LWS_WS_OPCODE_07__TEXT_FRAME:
case LWS_WS_OPCODE_07__BINARY_FRAME:
case LWS_WS_OPCODE_07__CONTINUATION:
break;
default:
lwsl_parser("passing opc %x up to exts\n",
wsi->u.ws.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->u.ws.rx_user_buffer[
LWS_SEND_BUFFER_PRE_PADDING];
eff_buf.token_len = wsi->u.ws.rx_user_buffer_head;
if (lws_ext_callback_for_each_active(wsi,
LWS_EXT_CALLBACK_EXTENDED_PAYLOAD_RX,
&eff_buf, 0) <= 0) /* not handle or fail */
lwsl_ext("ext opc opcode 0x%x unknown\n",
wsi->u.ws.opcode);
wsi->u.ws.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 lws_write
*/
eff_buf.token = &wsi->u.ws.rx_user_buffer[
LWS_SEND_BUFFER_PRE_PADDING];
eff_buf.token_len = wsi->u.ws.rx_user_buffer_head;
if (lws_ext_callback_for_each_active(wsi,
LWS_EXT_CALLBACK_PAYLOAD_RX, &eff_buf, 0) < 0)
return -1;
if (eff_buf.token_len > 0 ||
callback_action == LWS_CALLBACK_RECEIVE_PONG) {
eff_buf.token[eff_buf.token_len] = '\0';
if (wsi->protocol->callback) {
if (callback_action == LWS_CALLBACK_RECEIVE_PONG)
lwsl_info("Doing pong callback\n");
ret = user_callback_handle_rxflow(
wsi->protocol->callback,
lws_get_ctx(wsi),
wsi,
(enum lws_callback_reasons)callback_action,
wsi->user_space,
eff_buf.token,
eff_buf.token_len);
}
else
lwsl_err("No callback on payload spill!\n");
}
wsi->u.ws.rx_user_buffer_head = 0;
break;
}
return ret;
illegal_ctl_length:
lwsl_warn("Control frame with xtended length is illegal\n");
/* kill the connection */
return -1;
}
/**
* lws_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 lws_remaining_packet_payload() will return
* 0.
*
* Many protocols won't care becuse their packets are always small.
*/
LWS_VISIBLE size_t
lws_remaining_packet_payload(struct lws *wsi)
{
return wsi->u.ws.rx_packet_length;
}
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