/* * libwebsockets - small server side websockets and web server implementation * * Copyright (C) 2010-2014 Andy Green * * 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 (lws_is_flowcontrolled(wsi)) { lwsl_debug("%s: caching %ld\n", __func__, (long)len); lws_rxflow_cache(wsi, *buf, 0, len); return 0; } if (wsi->u.ws.rx_draining_ext) { #if !defined(LWS_NO_CLIENT) if (wsi->mode == LWSCM_WS_CLIENT) m = lws_client_rx_sm(wsi, 0); else #endif 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 %ld\n", __func__, (long)len); return 0; default: break; } return 0; } LWS_VISIBLE LWS_EXTERN void lws_client_http_body_pending(struct lws *wsi, int something_left_to_send) { wsi->client_http_body_pending = !!something_left_to_send; } 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]; const char *cce = NULL; unsigned char c; char *sb = p; int n = 0; ssize_t len = 0; #if defined(LWS_WITH_SOCKS5) char conn_mode = 0, pending_timeout = 0; #endif 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; #if defined(LWS_WITH_SOCKS5) /* SOCKS Greeting Reply */ case LWSCM_WSCL_WAITING_SOCKS_GREETING_REPLY: case LWSCM_WSCL_WAITING_SOCKS_AUTH_REPLY: case LWSCM_WSCL_WAITING_SOCKS_CONNECT_REPLY: /* handle proxy hung up on us */ if (pollfd->revents & LWS_POLLHUP) { lwsl_warn("SOCKS connection %p (fd=%d) dead\n", (void *)wsi, pollfd->fd); goto bail3; } n = recv(wsi->desc.sockfd, sb, context->pt_serv_buf_size, 0); if (n < 0) { if (LWS_ERRNO == LWS_EAGAIN) { lwsl_debug("SOCKS read EAGAIN, retrying\n"); return 0; } lwsl_err("ERROR reading from SOCKS socket\n"); goto bail3; } switch (wsi->mode) { case LWSCM_WSCL_WAITING_SOCKS_GREETING_REPLY: if (pt->serv_buf[0] != SOCKS_VERSION_5) goto socks_reply_fail; if (pt->serv_buf[1] == SOCKS_AUTH_NO_AUTH) { lwsl_client("SOCKS greeting reply: No Auth Method\n"); socks_generate_msg(wsi, SOCKS_MSG_CONNECT, &len); conn_mode = LWSCM_WSCL_WAITING_SOCKS_CONNECT_REPLY; pending_timeout = PENDING_TIMEOUT_AWAITING_SOCKS_CONNECT_REPLY; goto socks_send; } if (pt->serv_buf[1] == SOCKS_AUTH_USERNAME_PASSWORD) { lwsl_client("SOCKS greeting reply: User/Pw Method\n"); socks_generate_msg(wsi, SOCKS_MSG_USERNAME_PASSWORD, &len); conn_mode = LWSCM_WSCL_WAITING_SOCKS_AUTH_REPLY; pending_timeout = PENDING_TIMEOUT_AWAITING_SOCKS_AUTH_REPLY; goto socks_send; } goto socks_reply_fail; case LWSCM_WSCL_WAITING_SOCKS_AUTH_REPLY: if (pt->serv_buf[0] != SOCKS_SUBNEGOTIATION_VERSION_1 || pt->serv_buf[1] != SOCKS_SUBNEGOTIATION_STATUS_SUCCESS) goto socks_reply_fail; lwsl_client("SOCKS password OK, sending connect\n"); socks_generate_msg(wsi, SOCKS_MSG_CONNECT, &len); conn_mode = LWSCM_WSCL_WAITING_SOCKS_CONNECT_REPLY; pending_timeout = PENDING_TIMEOUT_AWAITING_SOCKS_CONNECT_REPLY; socks_send: n = send(wsi->desc.sockfd, (char *)pt->serv_buf, len, MSG_NOSIGNAL); if (n < 0) { lwsl_debug("ERROR writing to socks proxy\n"); goto bail3; } lws_set_timeout(wsi, pending_timeout, AWAITING_TIMEOUT); wsi->mode = conn_mode; break; socks_reply_fail: lwsl_notice("socks reply: v%d, err %d\n", pt->serv_buf[0], pt->serv_buf[1]); goto bail3; case LWSCM_WSCL_WAITING_SOCKS_CONNECT_REPLY: if (pt->serv_buf[0] != SOCKS_VERSION_5 || pt->serv_buf[1] != SOCKS_REQUEST_REPLY_SUCCESS) goto socks_reply_fail; lwsl_client("socks connect OK\n"); /* free stash since we are done with it */ lws_free_set_NULL(wsi->u.hdr.stash); if (lws_hdr_simple_create(wsi, _WSI_TOKEN_CLIENT_PEER_ADDRESS, wsi->vhost->socks_proxy_address)) goto bail3; wsi->c_port = wsi->vhost->socks_proxy_port; /* clear his proxy connection timeout */ lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0); goto start_ws_handshake; } break; #endif 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); goto bail3; } n = recv(wsi->desc.sockfd, sb, context->pt_serv_buf_size, 0); if (n < 0) { if (LWS_ERRNO == LWS_EAGAIN) { lwsl_debug("Proxy read returned EAGAIN... retrying\n"); return 0; } lwsl_err("ERROR reading from proxy socket\n"); goto bail3; } pt->serv_buf[13] = '\0'; if (strcmp(sb, "HTTP/1.0 200 ") && strcmp(sb, "HTTP/1.1 200 ")) { lwsl_err("ERROR proxy: %s\n", sb); goto bail3; } /* 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 defined(LWS_WITH_SOCKS5) start_ws_handshake: #endif 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) < 0) { cce = "bio_create failed"; goto bail3; } if (wsi->use_ssl) { n = lws_ssl_client_connect1(wsi); if (!n) return 0; if (n < 0) { cce = "lws_ssl_client_connect1 failed"; goto bail3; } } else wsi->ssl = NULL; /* fallthru */ case LWSCM_WSCL_WAITING_SSL: if (wsi->use_ssl) { n = lws_ssl_client_connect2(wsi); if (!n) return 0; if (n < 0) { cce = "lws_ssl_client_connect2 failed"; goto bail3; } } 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) { if (wsi->mode == LWSCM_RAW) return 0; 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; } if (wsi->client_http_body_pending) { wsi->mode = LWSCM_WSCL_ISSUE_HTTP_BODY; lws_set_timeout(wsi, PENDING_TIMEOUT_CLIENT_ISSUE_PAYLOAD, context->timeout_secs); /* user code must ask for writable callback */ break; } goto client_http_body_sent; case LWSCM_WSCL_ISSUE_HTTP_BODY: if (wsi->client_http_body_pending) { lws_set_timeout(wsi, PENDING_TIMEOUT_CLIENT_ISSUE_PAYLOAD, context->timeout_secs); /* user code must ask for writable callback */ break; } client_http_body_sent: 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 hanging up on us... * but if there is POLLIN waiting, handle that first */ if ((pollfd->revents & (LWS_POLLIN | LWS_POLLHUP)) == LWS_POLLHUP) { lwsl_debug("Server connection %p (fd=%d) dead\n", (void *)wsi, pollfd->fd); cce = "Peer hung up"; 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: cce = "read failed"; 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"); if (cce) lwsl_info("reason: %s\n", cce); wsi->protocol->callback(wsi, LWS_CALLBACK_CLIENT_CONNECTION_ERROR, wsi->user_space, (void *)cce, cce ? strlen(cce) : 0); wsi->already_did_cce = 1; 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) { #ifdef LWS_PLAT_OPTEE int tolower_optee(int c); *s = tolower_optee((int)*s); #else *s = tolower((int)*s); #endif s++; } } 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; } /* we don't support chained client connections yet */ return 1; #if 0 /* otherwise set ourselves up ready to go again */ wsi->state = LWSS_CLIENT_HTTP_ESTABLISHED; wsi->mode = LWSCM_HTTP_CLIENT_ACCEPTED; wsi->u.http.rx_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) { lws_header_table_force_to_detachable_state(wsi); 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; #endif } LWS_VISIBLE LWS_EXTERN unsigned int lws_http_client_http_response(struct lws *wsi) { if (!wsi->u.http.ah) return 0; return wsi->u.http.ah->http_response; } int lws_client_interpret_server_handshake(struct lws *wsi) { int n, len, okay = 0, port = 0, ssl = 0; int close_reason = LWS_CLOSE_STATUS_PROTOCOL_ERR; struct lws_context *context = wsi->context; const char *pc, *prot, *ads = NULL, *path, *cce = NULL; struct allocated_headers *ah = NULL; char *p, *q; char new_path[300]; #ifndef LWS_NO_EXTENSIONS 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->u.hdr.stash) lws_free_set_NULL(wsi->u.hdr.stash); ah = wsi->u.hdr.ah; if (!wsi->do_ws) { /* we are being an http client... */ lws_union_transition(wsi, LWSCM_HTTP_CLIENT_ACCEPTED); wsi->state = LWSS_CLIENT_HTTP_ESTABLISHED; wsi->u.http.ah = ah; ah->http_response = 0; } /* * 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"); cce = "HS: URI missing"; goto bail3; } if (!p) { p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP1_0); wsi->u.http.connection_type = HTTP_CONNECTION_CLOSE; } if (!p) { cce = "HS: URI missing"; lwsl_info("no URI\n"); goto bail3; } n = atoi(p); if (ah) ah->http_response = n; if (n == 301 || n == 302 || n == 303 || n == 307 || n == 308) { p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP_LOCATION); if (!p) { cce = "HS: Redirect code but no Location"; goto bail3; } /* Relative reference absolute path */ if (p[0] == '/') { #ifdef LWS_OPENSSL_SUPPORT ssl = wsi->use_ssl; #endif ads = lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_PEER_ADDRESS); port = wsi->c_port; path = p + 1; /* +1 as lws_client_reset expects leading / to be omitted */ } /* Absolute (Full) URI */ else if (strchr(p, ':')) { if (lws_parse_uri(p, &prot, &ads, &port, &path)) { cce = "HS: URI did not parse"; goto bail3; } if (!strcmp(prot, "wss") || !strcmp(prot, "https")) ssl = 1; } /* Relative reference relative path */ else { /* This doesn't try to calculate an absolute path, that will be left to the server */ #ifdef LWS_OPENSSL_SUPPORT ssl = wsi->use_ssl; #endif ads = lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_PEER_ADDRESS); port = wsi->c_port; path = new_path + 1; /* +1 as lws_client_reset expects leading / to be omitted */ strncpy(new_path, lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_URI), sizeof(new_path)); new_path[sizeof(new_path) - 1] = '\0'; q = strrchr(new_path, '/'); if (q) { strncpy(q + 1, p, sizeof(new_path) - (q - new_path) - 1); new_path[sizeof(new_path) - 1] = '\0'; } else { path = p; } } #ifdef LWS_OPENSSL_SUPPORT if (wsi->use_ssl && !ssl) { cce = "HS: Redirect attempted SSL downgrade"; goto bail3; } #endif if (!lws_client_reset(&wsi, ssl, ads, port, path, ads)) { /* there are two ways to fail out with NULL return... * simple, early problem where the wsi is intact, or * we went through with the reconnect attempt and the * wsi is already closed. In the latter case, the wsi * has beet set to NULL additionally. */ lwsl_err("Redirect failed\n"); cce = "HS: Redirect failed"; if (wsi) goto bail3; return 1; } return 0; } if (!wsi->do_ws) { #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"); cce = "HS: OOM"; 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.rx_content_length = atoll(lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP_CONTENT_LENGTH)); lwsl_notice("%s: incoming content length %llu\n", __func__, (unsigned long long)wsi->u.http.rx_content_length); wsi->u.http.rx_content_remain = wsi->u.http.rx_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)) { cce = "HS: disallowed by client filter"; 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)) { cce = "HS: disallowed at ESTABLISHED"; goto bail3; } /* free up his parsing allocations */ lws_header_table_detach(wsi, 0); lwsl_notice("%s: client connection up\n", __func__); return 0; } if (p && !strncmp(p, "401", 3)) { lwsl_warn( "lws_client_handshake: got bad HTTP response '%s'\n", p); cce = "HS: ws upgrade unauthorized"; goto bail3; } if (p && strncmp(p, "101", 3)) { lwsl_warn( "lws_client_handshake: got bad HTTP response '%s'\n", p); cce = "HS: ws upgrade response not 101"; goto bail3; } if (lws_hdr_total_length(wsi, WSI_TOKEN_ACCEPT) == 0) { lwsl_info("no ACCEPT\n"); cce = "HS: ACCEPT missing"; goto bail3; } p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_UPGRADE); if (!p) { lwsl_info("no UPGRADE\n"); cce = "HS: UPGRADE missing"; goto bail3; } strtolower(p); if (strcmp(p, "websocket")) { lwsl_warn( "lws_client_handshake: got bad Upgrade header '%s'\n", p); cce = "HS: Upgrade to something other than websocket"; goto bail3; } p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_CONNECTION); if (!p) { lwsl_info("no Connection hdr\n"); cce = "HS: CONNECTION missing"; goto bail3; } strtolower(p); if (strcmp(p, "upgrade")) { lwsl_warn("lws_client_int_s_hs: bad header %s\n", p); cce = "HS: UPGRADE malformed"; 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 */ n = 0; 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); cce = "HS: PROTOCOL malformed"; 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); cce = "HS: Cannot match protocol"; goto bail2; } check_extensions: /* * stitch protocol choice into the vh protocol linked list * We always insert ourselves at the start of the list * * X <-> B * X <-> pAn <-> pB */ //lwsl_err("%s: pre insert vhost start wsi %p, that wsi prev == %p\n", // __func__, // wsi->vhost->same_vh_protocol_list[n], // wsi->same_vh_protocol_prev); wsi->same_vh_protocol_prev = /* guy who points to us */ &wsi->vhost->same_vh_protocol_list[n]; wsi->same_vh_protocol_next = /* old first guy is our next */ wsi->vhost->same_vh_protocol_list[n]; /* we become the new first guy */ wsi->vhost->same_vh_protocol_list[n] = wsi; if (wsi->same_vh_protocol_next) /* old first guy points back to us now */ wsi->same_vh_protocol_next->same_vh_protocol_prev = &wsi->same_vh_protocol_next; #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, context->pt_serv_buf_size, WSI_TOKEN_EXTENSIONS) < 0) { lwsl_warn("ext list from server failed to copy\n"); cce = "HS: EXT: list too big"; 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_info(" 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))) { cce = "HS: EXT: failed setting defaults"; 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); cce = "HS: EXT: failed parsing defaults"; 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); cce = "HS: EXT: failed parsing options"; 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", __func__, ext->name, a); cce = "HS: EXT: Rejects server options"; goto bail2; } wsi->count_act_ext++; ext++; } if (n == 0) { lwsl_warn("Unknown ext '%s'!\n", ext_name); cce = "HS: EXT: unknown ext"; 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); cce = "HS: Accept hash wrong"; goto bail2; } /* allocate the per-connection user memory (if any) */ if (lws_ensure_user_space(wsi)) { lwsl_err("Problem allocating wsi user mem\n"); cce = "HS: OOM"; 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)) { cce = "HS: Rejected by filter cb"; 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; lws_restart_ws_ping_pong_timer(wsi); 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 = context->pt_serv_buf_size; n += LWS_PRE; wsi->u.ws.rx_ubuf = lws_malloc(n + 4 /* 0x0000ffff zlib */, "client frame buffer"); if (!wsi->u.ws.rx_ubuf) { lwsl_err("Out of Mem allocating rx buffer %d\n", n); cce = "HS: OOM"; goto bail2; } wsi->u.ws.rx_ubuf_alloc = n; lwsl_info("Allocating client RX buffer %d\n", n); #if !defined(LWS_WITH_ESP32) if (setsockopt(wsi->desc.sockfd, SOL_SOCKET, SO_SNDBUF, (const char *)&n, sizeof n)) { lwsl_warn("Failed to set SNDBUF to %d", n); cce = "HS: SO_SNDBUF failed"; goto bail3; } #endif 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)) { cce = "HS: Rejected at CLIENT_ESTABLISHED"; 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->protocol->callback(wsi, LWS_CALLBACK_CLIENT_CONNECTION_ERROR, wsi->user_space, (void *)cce, (unsigned int)strlen(cce)); wsi->already_did_cce = 1; 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 const char *pp = lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_SENT_PROTOCOLS); meth = lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_METHOD); if (!meth) { meth = "GET"; wsi->do_ws = 1; } else { wsi->do_ws = 0; } if (!strcmp(meth, "RAW")) { lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0); lwsl_notice("client transition to raw\n"); if (pp) { const struct lws_protocols *pr; pr = lws_vhost_name_to_protocol(wsi->vhost, pp); if (!pr) { lwsl_err("protocol %s not enabled on vhost\n", pp); return NULL; } lws_bind_protocol(wsi, pr); } if ((wsi->protocol->callback)(wsi, LWS_CALLBACK_RAW_ADOPT, wsi->user_space, NULL, 0)) return NULL; lws_header_table_force_to_detachable_state(wsi); lws_union_transition(wsi, LWSCM_RAW); lws_header_table_detach(wsi, 1); return NULL; } 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); 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)) { if (lws_check_opt(context->options, LWS_SERVER_OPTION_JUST_USE_RAW_ORIGIN)) p += sprintf(p, "Origin: %s\x0d\x0a", lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_ORIGIN)); else 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 */ if (wsi->protocol->callback(wsi, LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER, wsi->user_space, &p, (pkt + context->pt_serv_buf_size) - p - 12)) return NULL; p += sprintf(p, "\x0d\x0a"); return p; }