/*
* libwebsockets - small server side websockets and web server implementation
*
* Copyright (C) 2010-2014 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"
int
lws_handshake_client(struct lws *wsi, unsigned char **buf, size_t len)
{
int m;
switch (wsi->mode) {
case LWSCM_WSCL_WAITING_PROXY_REPLY:
case LWSCM_WSCL_ISSUE_HANDSHAKE:
case LWSCM_WSCL_WAITING_SERVER_REPLY:
case LWSCM_WSCL_WAITING_EXTENSION_CONNECT:
case LWSCM_WS_CLIENT:
while (len) {
/*
* we were accepting input but now we stopped doing so
*/
if (!(wsi->rxflow_change_to & LWS_RXFLOW_ALLOW)) {
lwsl_debug("%s: caching %d\n", __func__, len);
lws_rxflow_cache(wsi, *buf, 0, len);
return 0;
}
if (wsi->u.ws.rx_draining_ext) {
m = lws_rx_sm(wsi, 0);
if (m < 0)
return -1;
continue;
}
/* account for what we're using in rxflow buffer */
if (wsi->rxflow_buffer)
wsi->rxflow_pos++;
if (lws_client_rx_sm(wsi, *(*buf)++)) {
lwsl_debug("client_rx_sm exited\n");
return -1;
}
len--;
}
lwsl_debug("%s: finished with %d\n", __func__, len);
return 0;
default:
break;
}
return 0;
}
int
lws_client_socket_service(struct lws_context *context, struct lws *wsi,
struct lws_pollfd *pollfd)
{
struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
char *p = (char *)&pt->serv_buf[0];
char *sb = p;
unsigned char c;
int n, len;
switch (wsi->mode) {
case LWSCM_WSCL_WAITING_CONNECT:
/*
* we are under PENDING_TIMEOUT_SENT_CLIENT_HANDSHAKE
* timeout protection set in client-handshake.c
*/
if (!lws_client_connect_2(wsi)) {
/* closed */
lwsl_client("closed\n");
return -1;
}
/* either still pending connection, or changed mode */
return 0;
case LWSCM_WSCL_WAITING_PROXY_REPLY:
/* handle proxy hung up on us */
if (pollfd->revents & LWS_POLLHUP) {
lwsl_warn("Proxy connection %p (fd=%d) dead\n",
(void *)wsi, pollfd->fd);
lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
return 0;
}
n = recv(wsi->sock, sb, LWS_MAX_SOCKET_IO_BUF, 0);
if (n < 0) {
if (LWS_ERRNO == LWS_EAGAIN) {
lwsl_debug("Proxy read returned EAGAIN... retrying\n");
return 0;
}
lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
lwsl_err("ERROR reading from proxy socket\n");
return 0;
}
pt->serv_buf[13] = '\0';
if (strcmp(sb, "HTTP/1.0 200 ") &&
strcmp(sb, "HTTP/1.1 200 ")) {
lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
lwsl_err("ERROR proxy: %s\n", sb);
return 0;
}
/* clear his proxy connection timeout */
lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
/* fallthru */
case LWSCM_WSCL_ISSUE_HANDSHAKE:
/*
* we are under PENDING_TIMEOUT_SENT_CLIENT_HANDSHAKE
* timeout protection set in client-handshake.c
*
* take care of our lws_callback_on_writable
* happening at a time when there's no real connection yet
*/
if (lws_change_pollfd(wsi, LWS_POLLOUT, 0))
return -1;
#ifdef LWS_OPENSSL_SUPPORT
/* we can retry this... just cook the SSL BIO the first time */
if (wsi->use_ssl && !wsi->ssl)
lws_ssl_client_bio_create(wsi);
if (wsi->use_ssl) {
if (!lws_ssl_client_connect1(wsi))
return 0;
} else
wsi->ssl = NULL;
/* fallthru */
case LWSCM_WSCL_WAITING_SSL:
if (wsi->use_ssl) {
if (!lws_ssl_client_connect2(wsi))
return 0;
} else
wsi->ssl = NULL;
#endif
wsi->mode = LWSCM_WSCL_ISSUE_HANDSHAKE2;
lws_set_timeout(wsi, PENDING_TIMEOUT_AWAITING_CLIENT_HS_SEND,
context->timeout_secs);
/* fallthru */
case LWSCM_WSCL_ISSUE_HANDSHAKE2:
p = lws_generate_client_handshake(wsi, p);
if (p == NULL) {
lwsl_err("Failed to generate handshake for client\n");
lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
return 0;
}
/* send our request to the server */
lws_latency_pre(context, wsi);
n = lws_ssl_capable_write(wsi, (unsigned char *)sb, p - sb);
lws_latency(context, wsi, "send lws_issue_raw", n,
n == p - sb);
switch (n) {
case LWS_SSL_CAPABLE_ERROR:
lwsl_debug("ERROR writing to client socket\n");
lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
return 0;
case LWS_SSL_CAPABLE_MORE_SERVICE:
lws_callback_on_writable(wsi);
break;
}
wsi->u.hdr.parser_state = WSI_TOKEN_NAME_PART;
wsi->u.hdr.lextable_pos = 0;
wsi->mode = LWSCM_WSCL_WAITING_SERVER_REPLY;
lws_set_timeout(wsi, PENDING_TIMEOUT_AWAITING_SERVER_RESPONSE,
context->timeout_secs);
break;
case LWSCM_WSCL_WAITING_SERVER_REPLY:
/* handle server hung up on us */
if (pollfd->revents & LWS_POLLHUP) {
lwsl_debug("Server connection %p (fd=%d) dead\n",
(void *)wsi, pollfd->fd);
goto bail3;
}
if (!(pollfd->revents & LWS_POLLIN))
break;
/* interpret the server response */
/*
* HTTP/1.1 101 Switching Protocols
* Upgrade: websocket
* Connection: Upgrade
* Sec-WebSocket-Accept: me89jWimTRKTWwrS3aRrL53YZSo=
* Sec-WebSocket-Nonce: AQIDBAUGBwgJCgsMDQ4PEC==
* Sec-WebSocket-Protocol: chat
*/
/*
* we have to take some care here to only take from the
* socket bytewise. The browser may (and has been seen to
* in the case that onopen() performs websocket traffic)
* coalesce both handshake response and websocket traffic
* in one packet, since at that point the connection is
* definitively ready from browser pov.
*/
len = 1;
while (wsi->u.hdr.parser_state != WSI_PARSING_COMPLETE &&
len > 0) {
n = lws_ssl_capable_read(wsi, &c, 1);
lws_latency(context, wsi, "send lws_issue_raw", n,
n == 1);
switch (n) {
case 0:
case LWS_SSL_CAPABLE_ERROR:
goto bail3;
case LWS_SSL_CAPABLE_MORE_SERVICE:
return 0;
}
if (lws_parse(wsi, c)) {
lwsl_warn("problems parsing header\n");
goto bail3;
}
}
/*
* hs may also be coming in multiple packets, there is a 5-sec
* libwebsocket timeout still active here too, so if parsing did
* not complete just wait for next packet coming in this state
*/
if (wsi->u.hdr.parser_state != WSI_PARSING_COMPLETE)
break;
/*
* otherwise deal with the handshake. If there's any
* packet traffic already arrived we'll trigger poll() again
* right away and deal with it that way
*/
return lws_client_interpret_server_handshake(wsi);
bail3:
lwsl_info("closing conn at LWS_CONNMODE...SERVER_REPLY\n");
lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
return -1;
case LWSCM_WSCL_WAITING_EXTENSION_CONNECT:
lwsl_ext("LWSCM_WSCL_WAITING_EXTENSION_CONNECT\n");
break;
case LWSCM_WSCL_PENDING_CANDIDATE_CHILD:
lwsl_ext("LWSCM_WSCL_PENDING_CANDIDATE_CHILD\n");
break;
default:
break;
}
return 0;
}
/*
* In-place str to lower case
*/
static void
strtolower(char *s)
{
while (*s) {
*s = tolower((int)*s);
s++;
}
}
/**
* lws_http_transaction_completed() - wait for new http transaction or close
* @wsi: websocket connection
*
* Returns 1 if the HTTP connection must close now
* Returns 0 and resets connection to wait for new HTTP header /
* transaction if possible
*/
int LWS_WARN_UNUSED_RESULT
lws_http_transaction_completed_client(struct lws *wsi)
{
lwsl_debug("%s: wsi %p\n", __func__, wsi);
/* if we can't go back to accept new headers, drop the connection */
if (wsi->u.http.connection_type != HTTP_CONNECTION_KEEP_ALIVE) {
lwsl_info("%s: %p: close connection\n", __func__, wsi);
return 1;
}
/* otherwise set ourselves up ready to go again */
wsi->state = LWSS_CLIENT_HTTP_ESTABLISHED;
wsi->mode = LWSCM_HTTP_CLIENT_ACCEPTED;
wsi->u.http.content_length = 0;
wsi->hdr_parsing_completed = 0;
/* He asked for it to stay alive indefinitely */
lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
/*
* As client, nothing new is going to come until we ask for it
* we can drop the ah, if any
*/
if (wsi->u.hdr.ah) {
wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
lws_header_table_detach(wsi, 0);
}
/* If we're (re)starting on headers, need other implied init */
wsi->u.hdr.ues = URIES_IDLE;
lwsl_info("%s: %p: keep-alive await new transaction\n", __func__, wsi);
return 0;
}
int
lws_client_interpret_server_handshake(struct lws *wsi)
{
int n, len, okay = 0, isErrorCodeReceived = 0, port = 0, ssl = 0;
int close_reason = LWS_CLOSE_STATUS_PROTOCOL_ERR;
const char *pc, *prot, *ads = NULL, *path;
struct allocated_headers *ah;
char *p;
#ifndef LWS_NO_EXTENSIONS
struct lws_context *context = wsi->context;
struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
char *sb = (char *)&pt->serv_buf[0];
const struct lws_ext_options *opts;
const struct lws_extension *ext;
char ext_name[128];
const char *c, *a;
char ignore;
int more = 1;
void *v;
#endif
if (!wsi->do_ws) {
/* we are being an http client...
*/
ah = wsi->u.hdr.ah;
lws_union_transition(wsi, LWSCM_HTTP_CLIENT_ACCEPTED);
wsi->state = LWSS_CLIENT_HTTP_ESTABLISHED;
wsi->u.http.ah = ah;
}
/*
* well, what the server sent looked reasonable for syntax.
* Now let's confirm it sent all the necessary headers
*
* http (non-ws) client will expect something like this
*
* HTTP/1.0.200
* server:.libwebsockets
* content-type:.text/html
* content-length:.17703
* set-cookie:.test=LWS_1456736240_336776_COOKIE;Max-Age=360000
*
*
*
*/
wsi->u.http.connection_type = HTTP_CONNECTION_KEEP_ALIVE;
p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP);
if (wsi->do_ws && !p) {
lwsl_info("no URI\n");
goto bail3;
}
if (!p) {
p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP1_0);
wsi->u.http.connection_type = HTTP_CONNECTION_CLOSE;
}
if (!p) {
lwsl_info("no URI\n");
goto bail3;
}
n = atoi(p);
if (n == 301 || n == 302 || n == 303 || n == 307 || n == 308) {
p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP_LOCATION);
if (!p)
goto bail3;
if (lws_parse_uri(p, &prot, &ads, &port, &path))
goto bail3;
if (!strcmp(prot, "wss://") || !strcmp(prot, "https://"))
ssl = 1;
if (lws_client_reset(wsi, ssl, ads, port, path, ads)) {
lwsl_err("Redirect failed\n");
goto bail3;
}
return 0;
}
if (!wsi->do_ws) {
if (n != 200) {
lwsl_notice("Connection failed with code %d", n);
goto bail2;
}
#ifdef LWS_WITH_HTTP_PROXY
wsi->perform_rewrite = 0;
if (lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_CONTENT_TYPE)) {
if (!strncmp(lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP_CONTENT_TYPE),
"text/html", 9))
wsi->perform_rewrite = 1;
}
#endif
/* allocate the per-connection user memory (if any) */
if (lws_ensure_user_space(wsi)) {
lwsl_err("Problem allocating wsi user mem\n");
goto bail2;
}
/* he may choose to send us stuff in chunked transfer-coding */
wsi->chunked = 0;
wsi->chunk_remaining = 0; /* ie, next thing is chunk size */
if (lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_TRANSFER_ENCODING)) {
wsi->chunked = !strcmp(lws_hdr_simple_ptr(wsi,
WSI_TOKEN_HTTP_TRANSFER_ENCODING),
"chunked");
/* first thing is hex, after payload there is crlf */
wsi->chunk_parser = ELCP_HEX;
}
if (lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_CONTENT_LENGTH)) {
wsi->u.http.content_length =
atoi(lws_hdr_simple_ptr(wsi,
WSI_TOKEN_HTTP_CONTENT_LENGTH));
lwsl_notice("%s: incoming content length %d\n", __func__,
wsi->u.http.content_length);
wsi->u.http.content_remain = wsi->u.http.content_length;
} else /* can't do 1.1 without a content length or chunked */
if (!wsi->chunked)
wsi->u.http.connection_type = HTTP_CONNECTION_CLOSE;
/*
* we seem to be good to go, give client last chance to check
* headers and OK it
*/
if (wsi->protocol->callback(wsi, LWS_CALLBACK_CLIENT_FILTER_PRE_ESTABLISH,
wsi->user_space, NULL, 0))
goto bail2;
/* clear his proxy connection timeout */
lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
wsi->rxflow_change_to = LWS_RXFLOW_ALLOW;
/* call him back to inform him he is up */
if (wsi->protocol->callback(wsi,
LWS_CALLBACK_ESTABLISHED_CLIENT_HTTP,
wsi->user_space, NULL, 0))
goto bail3;
/* free up his parsing allocations */
lws_header_table_detach(wsi, 0);
lwsl_notice("%s: client connection up\n", __func__);
return 0;
}
if (lws_hdr_total_length(wsi, WSI_TOKEN_ACCEPT) == 0) {
lwsl_info("no ACCEPT\n");
isErrorCodeReceived = 1;
goto bail3;
}
if (p && strncmp(p, "101", 3)) {
lwsl_warn(
"lws_client_handshake: got bad HTTP response '%s'\n", p);
goto bail3;
}
p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_UPGRADE);
if (!p) {
lwsl_info("no UPGRADE\n");
goto bail3;
}
strtolower(p);
if (strcmp(p, "websocket")) {
lwsl_warn(
"lws_client_handshake: got bad Upgrade header '%s'\n", p);
goto bail3;
}
p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_CONNECTION);
if (!p) {
lwsl_info("no Connection hdr\n");
goto bail3;
}
strtolower(p);
if (strcmp(p, "upgrade")) {
lwsl_warn("lws_client_int_s_hs: bad header %s\n", p);
goto bail3;
}
pc = lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_SENT_PROTOCOLS);
if (!pc) {
lwsl_parser("lws_client_int_s_hs: no protocol list\n");
} else
lwsl_parser("lws_client_int_s_hs: protocol list '%s'\n", pc);
/*
* confirm the protocol the server wants to talk was in the list
* of protocols we offered
*/
len = lws_hdr_total_length(wsi, WSI_TOKEN_PROTOCOL);
if (!len) {
lwsl_info("lws_client_int_s_hs: WSI_TOKEN_PROTOCOL is null\n");
/*
* no protocol name to work from,
* default to first protocol
*/
wsi->protocol = &wsi->vhost->protocols[0];
goto check_extensions;
}
p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_PROTOCOL);
len = strlen(p);
while (pc && *pc && !okay) {
if (!strncmp(pc, p, len) &&
(pc[len] == ',' || pc[len] == '\0')) {
okay = 1;
continue;
}
while (*pc && *pc++ != ',')
;
while (*pc && *pc == ' ')
pc++;
}
if (!okay) {
lwsl_err("lws_client_int_s_hs: got bad protocol %s\n", p);
goto bail2;
}
/*
* identify the selected protocol struct and set it
*/
n = 0;
wsi->protocol = NULL;
while (wsi->vhost->protocols[n].callback && !wsi->protocol) {
if (strcmp(p, wsi->vhost->protocols[n].name) == 0) {
wsi->protocol = &wsi->vhost->protocols[n];
break;
}
n++;
}
if (wsi->protocol == NULL) {
lwsl_err("lws_client_int_s_hs: fail protocol %s\n", p);
goto bail2;
}
check_extensions:
#ifndef LWS_NO_EXTENSIONS
/* instantiate the accepted extensions */
if (!lws_hdr_total_length(wsi, WSI_TOKEN_EXTENSIONS)) {
lwsl_ext("no client extensions allowed by server\n");
goto check_accept;
}
/*
* break down the list of server accepted extensions
* and go through matching them or identifying bogons
*/
if (lws_hdr_copy(wsi, sb, LWS_MAX_SOCKET_IO_BUF, WSI_TOKEN_EXTENSIONS) < 0) {
lwsl_warn("ext list from server failed to copy\n");
goto bail2;
}
c = sb;
n = 0;
ignore = 0;
a = NULL;
while (more) {
if (*c && (*c != ',' && *c != '\t')) {
if (*c == ';') {
ignore = 1;
if (!a)
a = c + 1;
}
if (ignore || *c == ' ') {
c++;
continue;
}
ext_name[n] = *c++;
if (n < sizeof(ext_name) - 1)
n++;
continue;
}
ext_name[n] = '\0';
ignore = 0;
if (!*c)
more = 0;
else {
c++;
if (!n)
continue;
}
/* check we actually support it */
lwsl_notice("checking client ext %s\n", ext_name);
n = 0;
ext = wsi->vhost->extensions;
while (ext && ext->callback) {
if (strcmp(ext_name, ext->name)) {
ext++;
continue;
}
n = 1;
lwsl_notice("instantiating client ext %s\n", ext_name);
/* instantiate the extension on this conn */
wsi->active_extensions[wsi->count_act_ext] = ext;
/* allow him to construct his ext instance */
if (ext->callback(lws_get_context(wsi), ext, wsi,
LWS_EXT_CB_CLIENT_CONSTRUCT,
(void *)&wsi->act_ext_user[wsi->count_act_ext],
(void *)&opts, 0)) {
lwsl_notice(" ext %s failed construction\n", ext_name);
ext++;
continue;
}
/*
* allow the user code to override ext defaults if it
* wants to
*/
ext_name[0] = '\0';
if (user_callback_handle_rxflow(wsi->protocol->callback,
wsi, LWS_CALLBACK_WS_EXT_DEFAULTS,
(char *)ext->name, ext_name,
sizeof(ext_name)))
goto bail2;
if (ext_name[0] &&
lws_ext_parse_options(ext, wsi, wsi->act_ext_user[
wsi->count_act_ext], opts, ext_name,
strlen(ext_name))) {
lwsl_err("%s: unable to parse user defaults '%s'",
__func__, ext_name);
goto bail2;
}
/*
* give the extension the server options
*/
if (a && lws_ext_parse_options(ext, wsi,
wsi->act_ext_user[wsi->count_act_ext],
opts, a, c - a)) {
lwsl_err("%s: unable to parse remote def '%s'",
__func__, a);
goto bail2;
}
if (ext->callback(lws_get_context(wsi), ext, wsi,
LWS_EXT_CB_OPTION_CONFIRM,
wsi->act_ext_user[wsi->count_act_ext],
NULL, 0)) {
lwsl_err("%s: ext %s rejects server options %s",
ext->name, a);
goto bail2;
}
wsi->count_act_ext++;
ext++;
}
if (n == 0) {
lwsl_warn("Unknown ext '%s'!\n", ext_name);
goto bail2;
}
a = NULL;
n = 0;
}
check_accept:
#endif
/*
* Confirm his accept token is the one we precomputed
*/
p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_ACCEPT);
if (strcmp(p, wsi->u.hdr.ah->initial_handshake_hash_base64)) {
lwsl_warn("lws_client_int_s_hs: accept '%s' wrong vs '%s'\n", p,
wsi->u.hdr.ah->initial_handshake_hash_base64);
goto bail2;
}
/* allocate the per-connection user memory (if any) */
if (lws_ensure_user_space(wsi)) {
lwsl_err("Problem allocating wsi user mem\n");
goto bail2;
}
/*
* we seem to be good to go, give client last chance to check
* headers and OK it
*/
if (wsi->protocol->callback(wsi, LWS_CALLBACK_CLIENT_FILTER_PRE_ESTABLISH,
wsi->user_space, NULL, 0))
goto bail2;
/* clear his proxy connection timeout */
lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
/* free up his parsing allocations */
lws_header_table_detach(wsi, 0);
lws_union_transition(wsi, LWSCM_WS_CLIENT);
wsi->state = LWSS_ESTABLISHED;
wsi->rxflow_change_to = LWS_RXFLOW_ALLOW;
/*
* create the frame buffer for this connection according to the
* size mentioned in the protocol definition. If 0 there, then
* use a big default for compatibility
*/
n = wsi->protocol->rx_buffer_size;
if (!n)
n = LWS_MAX_SOCKET_IO_BUF;
n += LWS_PRE;
wsi->u.ws.rx_ubuf = lws_malloc(n + 4 /* 0x0000ffff zlib */);
if (!wsi->u.ws.rx_ubuf) {
lwsl_err("Out of Mem allocating rx buffer %d\n", n);
goto bail2;
}
wsi->u.ws.rx_ubuf_alloc = n;
lwsl_info("Allocating client RX buffer %d\n", n);
if (setsockopt(wsi->sock, SOL_SOCKET, SO_SNDBUF, (const char *)&n,
sizeof n)) {
lwsl_warn("Failed to set SNDBUF to %d", n);
goto bail3;
}
lwsl_debug("handshake OK for protocol %s\n", wsi->protocol->name);
/* call him back to inform him he is up */
if (wsi->protocol->callback(wsi, LWS_CALLBACK_CLIENT_ESTABLISHED,
wsi->user_space, NULL, 0))
goto bail3;
#ifndef LWS_NO_EXTENSIONS
/*
* inform all extensions, not just active ones since they
* already know
*/
ext = wsi->vhost->extensions;
while (ext && ext->callback) {
v = NULL;
for (n = 0; n < wsi->count_act_ext; n++)
if (wsi->active_extensions[n] == ext)
v = wsi->act_ext_user[n];
ext->callback(context, ext, wsi,
LWS_EXT_CB_ANY_WSI_ESTABLISHED, v, NULL, 0);
ext++;
}
#endif
return 0;
bail3:
close_reason = LWS_CLOSE_STATUS_NOSTATUS;
bail2:
if (wsi->protocol && wsi->state == LWSS_ESTABLISHED) {
if (isErrorCodeReceived && p) {
wsi->protocol->callback(wsi,
LWS_CALLBACK_CLIENT_CONNECTION_ERROR,
wsi->user_space, p,
(unsigned int)strlen(p));
} else {
wsi->protocol->callback(wsi,
LWS_CALLBACK_CLIENT_CONNECTION_ERROR,
wsi->user_space, NULL, 0);
}
}
lwsl_info("closing connection due to bail2 connection error\n");
/* closing will free up his parsing allocations */
lws_close_free_wsi(wsi, close_reason);
return 1;
}
char *
lws_generate_client_handshake(struct lws *wsi, char *pkt)
{
char buf[128], hash[20], key_b64[40], *p = pkt;
struct lws_context *context = wsi->context;
const char *meth;
int n;
#ifndef LWS_NO_EXTENSIONS
const struct lws_extension *ext;
int ext_count = 0;
#endif
meth = lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_METHOD);
if (!meth) {
meth = "GET";
wsi->do_ws = 1;
} else
wsi->do_ws = 0;
if (wsi->do_ws) {
/*
* create the random key
*/
n = lws_get_random(context, hash, 16);
if (n != 16) {
lwsl_err("Unable to read from random dev %s\n",
SYSTEM_RANDOM_FILEPATH);
lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
return NULL;
}
lws_b64_encode_string(hash, 16, key_b64, sizeof(key_b64));
}
/*
* 04 example client handshake
*
* GET /chat HTTP/1.1
* Host: server.example.com
* Upgrade: websocket
* Connection: Upgrade
* Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==
* Sec-WebSocket-Origin: http://example.com
* Sec-WebSocket-Protocol: chat, superchat
* Sec-WebSocket-Version: 4
*/
p += sprintf(p, "%s %s HTTP/1.1\x0d\x0a", meth,
lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_URI));
p += sprintf(p, "Pragma: no-cache\x0d\x0a"
"Cache-Control: no-cache\x0d\x0a");
p += sprintf(p, "Host: %s\x0d\x0a",
lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_HOST));
if (lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_ORIGIN))
p += sprintf(p, "Origin: http://%s\x0d\x0a",
lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_ORIGIN));
if (wsi->do_ws) {
p += sprintf(p, "Upgrade: websocket\x0d\x0a"
"Connection: Upgrade\x0d\x0a"
"Sec-WebSocket-Key: ");
strcpy(p, key_b64);
p += strlen(key_b64);
p += sprintf(p, "\x0d\x0a");
if (lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_SENT_PROTOCOLS))
p += sprintf(p, "Sec-WebSocket-Protocol: %s\x0d\x0a",
lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_SENT_PROTOCOLS));
/* tell the server what extensions we could support */
#ifndef LWS_NO_EXTENSIONS
ext = wsi->vhost->extensions;
while (ext && ext->callback) {
n = lws_ext_cb_all_exts(context, wsi,
LWS_EXT_CB_CHECK_OK_TO_PROPOSE_EXTENSION,
(char *)ext->name, 0);
if (n) { /* an extension vetos us */
lwsl_ext("ext %s vetoed\n", (char *)ext->name);
ext++;
continue;
}
n = wsi->vhost->protocols[0].callback(wsi,
LWS_CALLBACK_CLIENT_CONFIRM_EXTENSION_SUPPORTED,
wsi->user_space, (char *)ext->name, 0);
/*
* zero return from callback means
* go ahead and allow the extension,
* it's what we get if the callback is
* unhandled
*/
if (n) {
ext++;
continue;
}
/* apply it */
if (ext_count)
*p++ = ',';
else
p += sprintf(p, "Sec-WebSocket-Extensions: ");
p += sprintf(p, "%s", ext->client_offer);
ext_count++;
ext++;
}
if (ext_count)
p += sprintf(p, "\x0d\x0a");
#endif
if (wsi->ietf_spec_revision)
p += sprintf(p, "Sec-WebSocket-Version: %d\x0d\x0a",
wsi->ietf_spec_revision);
/* prepare the expected server accept response */
key_b64[39] = '\0'; /* enforce composed length below buf sizeof */
n = sprintf(buf, "%s258EAFA5-E914-47DA-95CA-C5AB0DC85B11", key_b64);
lws_SHA1((unsigned char *)buf, n, (unsigned char *)hash);
lws_b64_encode_string(hash, 20,
wsi->u.hdr.ah->initial_handshake_hash_base64,
sizeof(wsi->u.hdr.ah->initial_handshake_hash_base64));
}
/* give userland a chance to append, eg, cookies */
wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER,
NULL, &p, (pkt + LWS_MAX_SOCKET_IO_BUF) - p - 12);
p += sprintf(p, "\x0d\x0a");
return p;
}