1 /*
2  * libwebsockets - small server side websockets and web server implementation
3  *
4  * Copyright (C) 2010 - 2020 Andy Green <andy@warmcat.com>
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to
8  * deal in the Software without restriction, including without limitation the
9  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10  * sell copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
22  * IN THE SOFTWARE.
23  */
24 
25 #include "private-lib-core.h"
26 
27 #if defined(LWS_WITH_TLS)
28 int
lws_client_create_tls(struct lws * wsi,const char ** pcce,int do_c1)29 lws_client_create_tls(struct lws *wsi, const char **pcce, int do_c1)
30 {
31 	int n;
32 
33 	/* we can retry this... just cook the SSL BIO the first time */
34 
35 	if (wsi->tls.use_ssl & LCCSCF_USE_SSL) {
36 
37 		if (!wsi->tls.ssl) {
38 			if (lws_ssl_client_bio_create(wsi) < 0) {
39 				*pcce = "bio_create failed";
40 				return -1;
41 			}
42 
43 			if (!wsi->transaction_from_pipeline_queue &&
44 			    lws_tls_restrict_borrow(wsi->context)) {
45 				*pcce = "tls restriction limit";
46 				return -1;
47 			}
48 		}
49 
50 		if (!do_c1)
51 			return 0;
52 
53 		n = lws_ssl_client_connect1(wsi);
54 		if (!n)
55 			return 1; /* caller should return 0 */
56 		if (n < 0) {
57 			*pcce = "lws_ssl_client_connect1 failed";
58 			return -1;
59 		}
60 	} else
61 		wsi->tls.ssl = NULL;
62 
63 #if defined (LWS_WITH_HTTP2)
64 	if (wsi->client_h2_alpn) {
65 		/*
66 		 * We connected to the server and set up tls, and
67 		 * negotiated "h2".
68 		 *
69 		 * So this is it, we are an h2 master client connection
70 		 * now, not an h1 client connection.
71 		 */
72 #if defined(LWS_WITH_TLS)
73 		lws_tls_server_conn_alpn(wsi);
74 #endif
75 
76 		/* send the H2 preface to legitimize the connection */
77 		if (lws_h2_issue_preface(wsi)) {
78 			*pcce = "error sending h2 preface";
79 			return -1;
80 		}
81 	}
82 #endif
83 
84 	return 0; /* OK */
85 }
86 
87 #endif
88 
89 void
lws_client_http_body_pending(struct lws * wsi,int something_left_to_send)90 lws_client_http_body_pending(struct lws *wsi, int something_left_to_send)
91 {
92 	wsi->client_http_body_pending = !!something_left_to_send;
93 }
94 
95 int
lws_client_socket_service(struct lws * wsi,struct lws_pollfd * pollfd)96 lws_client_socket_service(struct lws *wsi, struct lws_pollfd *pollfd)
97 {
98 	struct lws_context *context = wsi->context;
99 	struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
100 	char *p = (char *)&pt->serv_buf[0];
101 #if defined(LWS_WITH_TLS)
102 	char ebuf[128];
103 #endif
104 	const char *cce = NULL;
105 	char *sb = p;
106 	int n = 0;
107 
108 	switch (lwsi_state(wsi)) {
109 
110 	case LRS_WAITING_DNS:
111 		/*
112 		 * we are under PENDING_TIMEOUT_SENT_CLIENT_HANDSHAKE
113 		 * timeout protection set in client-handshake.c
114 		 */
115 		lwsl_err("%s: wsi %p: WAITING_DNS\n", __func__, wsi);
116 		if (!lws_client_connect_2_dnsreq(wsi)) {
117 			/* closed */
118 			lwsl_client("closed\n");
119 			return -1;
120 		}
121 
122 		/* either still pending connection, or changed mode */
123 		return 0;
124 
125 	case LRS_WAITING_CONNECT:
126 
127 		/*
128 		 * we are under PENDING_TIMEOUT_SENT_CLIENT_HANDSHAKE
129 		 * timeout protection set in client-handshake.c
130 		 */
131 		if (pollfd->revents & LWS_POLLOUT)
132 			lws_client_connect_3_connect(wsi, NULL, NULL, 0, NULL);
133 		break;
134 
135 #if defined(LWS_WITH_SOCKS5)
136 	/* SOCKS Greeting Reply */
137 	case LRS_WAITING_SOCKS_GREETING_REPLY:
138 	case LRS_WAITING_SOCKS_AUTH_REPLY:
139 	case LRS_WAITING_SOCKS_CONNECT_REPLY:
140 
141 		switch (lws_socks5c_handle_state(wsi, pollfd, &cce)) {
142 		case LW5CHS_RET_RET0:
143 			return 0;
144 		case LW5CHS_RET_BAIL3:
145 			goto bail3;
146 		case LW5CHS_RET_STARTHS:
147 			goto start_ws_handshake;
148 		default:
149 			break;
150 		}
151 		break;
152 #endif
153 
154 #if defined(LWS_CLIENT_HTTP_PROXYING) && (defined(LWS_ROLE_H1) || defined(LWS_ROLE_H2))
155 
156 	case LRS_WAITING_PROXY_REPLY:
157 
158 		/* handle proxy hung up on us */
159 
160 		if (pollfd->revents & LWS_POLLHUP) {
161 
162 			lwsl_warn("Proxy connection %p (fd=%d) dead\n",
163 				  (void *)wsi, pollfd->fd);
164 
165 			cce = "proxy conn dead";
166 			goto bail3;
167 		}
168 
169 		n = recv(wsi->desc.sockfd, sb, context->pt_serv_buf_size, 0);
170 		if (n < 0) {
171 			if (LWS_ERRNO == LWS_EAGAIN) {
172 				lwsl_debug("Proxy read EAGAIN... retrying\n");
173 				return 0;
174 			}
175 			lwsl_err("ERROR reading from proxy socket\n");
176 			cce = "proxy read err";
177 			goto bail3;
178 		}
179 
180 		pt->serv_buf[13] = '\0';
181 		if (n < 13 || (strncmp(sb, "HTTP/1.0 200 ", 13) &&
182 		    strncmp(sb, "HTTP/1.1 200 ", 13))) {
183 			lwsl_err("%s: ERROR proxy did not reply with h1\n",
184 					__func__);
185 			/* lwsl_hexdump_notice(sb, n); */
186 			cce = "proxy not h1";
187 			goto bail3;
188 		}
189 
190 		lwsl_info("%s: proxy connection extablished\n", __func__);
191 
192 		/* clear his proxy connection timeout */
193 
194 		lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
195 
196 		/* fallthru */
197 
198 #endif
199 
200 	case LRS_H1C_ISSUE_HANDSHAKE:
201 
202 		/*
203 		 * we are under PENDING_TIMEOUT_SENT_CLIENT_HANDSHAKE
204 		 * timeout protection set in client-handshake.c
205 		 *
206 		 * take care of our lws_callback_on_writable
207 		 * happening at a time when there's no real connection yet
208 		 */
209 #if defined(LWS_WITH_SOCKS5)
210 start_ws_handshake:
211 #endif
212 		if (lws_change_pollfd(wsi, LWS_POLLOUT, 0))
213 			return -1;
214 
215 #if defined(LWS_WITH_TLS)
216 		n = lws_client_create_tls(wsi, &cce, 1);
217 		if (n < 0)
218 			goto bail3;
219 		if (n == 1)
220 			return 0;
221 
222 		/* fallthru */
223 
224 	case LRS_WAITING_SSL:
225 
226 		if (wsi->tls.use_ssl & LCCSCF_USE_SSL) {
227 			n = lws_ssl_client_connect2(wsi, ebuf, sizeof(ebuf));
228 			if (!n)
229 				return 0;
230 			if (n < 0) {
231 				cce = ebuf;
232 				goto bail3;
233 			}
234 		} else
235 			wsi->tls.ssl = NULL;
236 #endif
237 #if defined(LWS_WITH_DETAILED_LATENCY)
238 		if (context->detailed_latency_cb) {
239 			wsi->detlat.type = LDLT_TLS_NEG_CLIENT;
240 			wsi->detlat.latencies[LAT_DUR_PROXY_CLIENT_REQ_TO_WRITE] =
241 				lws_now_usecs() -
242 				wsi->detlat.earliest_write_req_pre_write;
243 			wsi->detlat.latencies[LAT_DUR_USERCB] = 0;
244 			lws_det_lat_cb(wsi->context, &wsi->detlat);
245 		}
246 #endif
247 #if defined (LWS_WITH_HTTP2)
248 		if (wsi->client_h2_alpn) {
249 			/*
250 			 * We connected to the server and set up tls, and
251 			 * negotiated "h2".
252 			 *
253 			 * So this is it, we are an h2 master client connection
254 			 * now, not an h1 client connection.
255 			 */
256 #if defined(LWS_WITH_TLS)
257 			lws_tls_server_conn_alpn(wsi);
258 #endif
259 
260 			/* send the H2 preface to legitimize the connection */
261 			if (lws_h2_issue_preface(wsi)) {
262 				cce = "error sending h2 preface";
263 				goto bail3;
264 			}
265 
266 		//	lwsi_set_state(wsi, LRS_H1C_ISSUE_HANDSHAKE2);
267 			lws_set_timeout(wsi, PENDING_TIMEOUT_AWAITING_CLIENT_HS_SEND,
268 					context->timeout_secs);
269 
270 			break;
271 		}
272 #endif
273 
274 		/* fallthru */
275 
276 	case LRS_H1C_ISSUE_HANDSHAKE2:
277 		p = lws_generate_client_handshake(wsi, p);
278 		if (p == NULL) {
279 			if (wsi->role_ops == &role_ops_raw_skt
280 #if defined(LWS_ROLE_RAW_FILE)
281 				|| wsi->role_ops == &role_ops_raw_file
282 #endif
283 			    )
284 				return 0;
285 
286 			lwsl_err("Failed to generate handshake for client\n");
287 			lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS,
288 					   "chs");
289 			return 0;
290 		}
291 
292 		/* send our request to the server */
293 
294 		lwsl_info("%s: HANDSHAKE2: %p: sending headers "
295 			  "(wsistate 0x%lx), w sock %d\n",
296 			  __func__, wsi, (unsigned long)wsi->wsistate,
297 			  wsi->desc.sockfd);
298 #if defined(LWS_WITH_DETAILED_LATENCY)
299 		wsi->detlat.earliest_write_req_pre_write = lws_now_usecs();
300 #endif
301 		n = lws_ssl_capable_write(wsi, (unsigned char *)sb, (int)(p - sb));
302 		switch (n) {
303 		case LWS_SSL_CAPABLE_ERROR:
304 			lwsl_debug("ERROR writing to client socket\n");
305 			lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS,
306 					   "cws");
307 			return 0;
308 		case LWS_SSL_CAPABLE_MORE_SERVICE:
309 			lws_callback_on_writable(wsi);
310 			break;
311 		}
312 
313 		if (wsi->client_http_body_pending) {
314 			lwsl_debug("body pending\n");
315 			lwsi_set_state(wsi, LRS_ISSUE_HTTP_BODY);
316 			lws_set_timeout(wsi,
317 					PENDING_TIMEOUT_CLIENT_ISSUE_PAYLOAD,
318 					context->timeout_secs);
319 
320 			if (wsi->flags & LCCSCF_HTTP_X_WWW_FORM_URLENCODED)
321 				lws_callback_on_writable(wsi);
322 #if defined(LWS_WITH_HTTP_PROXY)
323 			if (wsi->http.proxy_clientside)
324 				lws_callback_on_writable(wsi);
325 #endif
326 			/* user code must ask for writable callback */
327 			break;
328 		}
329 
330 		lwsi_set_state(wsi, LRS_WAITING_SERVER_REPLY);
331 		wsi->hdr_parsing_completed = 0;
332 
333 		if (lwsi_state(wsi) == LRS_IDLING) {
334 			lwsi_set_state(wsi, LRS_WAITING_SERVER_REPLY);
335 			wsi->hdr_parsing_completed = 0;
336 #if defined(LWS_ROLE_H1) || defined(LWS_ROLE_H2)
337 			wsi->http.ah->parser_state = WSI_TOKEN_NAME_PART;
338 			wsi->http.ah->lextable_pos = 0;
339 #if defined(LWS_WITH_CUSTOM_HEADERS)
340 			wsi->http.ah->unk_pos = 0;
341 #endif
342 			/* If we're (re)starting on hdr, need other implied init */
343 			wsi->http.ah->ues = URIES_IDLE;
344 #endif
345 		}
346 
347 		lws_set_timeout(wsi, PENDING_TIMEOUT_AWAITING_SERVER_RESPONSE,
348 				wsi->context->timeout_secs);
349 
350 		lws_callback_on_writable(wsi);
351 
352 		goto client_http_body_sent;
353 
354 	case LRS_ISSUE_HTTP_BODY:
355 #if defined(LWS_WITH_HTTP_PROXY)
356 			if (wsi->http.proxy_clientside) {
357 				lws_callback_on_writable(wsi);
358 				break;
359 			}
360 #endif
361 		if (wsi->client_http_body_pending) {
362 			//lws_set_timeout(wsi,
363 			//		PENDING_TIMEOUT_CLIENT_ISSUE_PAYLOAD,
364 			//		context->timeout_secs);
365 			/* user code must ask for writable callback */
366 			break;
367 		}
368 client_http_body_sent:
369 #if defined(LWS_ROLE_H1) || defined(LWS_ROLE_H2)
370 		/* prepare ourselves to do the parsing */
371 		wsi->http.ah->parser_state = WSI_TOKEN_NAME_PART;
372 		wsi->http.ah->lextable_pos = 0;
373 #if defined(LWS_WITH_CUSTOM_HEADERS)
374 		wsi->http.ah->unk_pos = 0;
375 #endif
376 #endif
377 		lwsi_set_state(wsi, LRS_WAITING_SERVER_REPLY);
378 		lws_set_timeout(wsi, PENDING_TIMEOUT_AWAITING_SERVER_RESPONSE,
379 				context->timeout_secs);
380 		break;
381 
382 	case LRS_WAITING_SERVER_REPLY:
383 		/*
384 		 * handle server hanging up on us...
385 		 * but if there is POLLIN waiting, handle that first
386 		 */
387 		if ((pollfd->revents & (LWS_POLLIN | LWS_POLLHUP)) ==
388 								LWS_POLLHUP) {
389 
390 			lwsl_debug("Server connection %p (fd=%d) dead\n",
391 				(void *)wsi, pollfd->fd);
392 			cce = "Peer hung up";
393 			goto bail3;
394 		}
395 
396 		if (!(pollfd->revents & LWS_POLLIN))
397 			break;
398 
399 #if defined(LWS_ROLE_H1) || defined(LWS_ROLE_H2)
400 		/* interpret the server response
401 		 *
402 		 *  HTTP/1.1 101 Switching Protocols
403 		 *  Upgrade: websocket
404 		 *  Connection: Upgrade
405 		 *  Sec-WebSocket-Accept: me89jWimTRKTWwrS3aRrL53YZSo=
406 		 *  Sec-WebSocket-Nonce: AQIDBAUGBwgJCgsMDQ4PEC==
407 		 *  Sec-WebSocket-Protocol: chat
408 		 *
409 		 * we have to take some care here to only take from the
410 		 * socket bytewise.  The browser may (and has been seen to
411 		 * in the case that onopen() performs websocket traffic)
412 		 * coalesce both handshake response and websocket traffic
413 		 * in one packet, since at that point the connection is
414 		 * definitively ready from browser pov.
415 		 */
416 		while (wsi->http.ah->parser_state != WSI_PARSING_COMPLETE) {
417 			struct lws_tokens eb;
418 			int n, m, buffered;
419 
420 			eb.token = NULL;
421 			eb.len = 0;
422 			buffered = lws_buflist_aware_read(pt, wsi, &eb, 0, __func__);
423 			lwsl_debug("%s: buflist-aware-read %d %d\n", __func__,
424 					buffered, eb.len);
425 			if (eb.len == LWS_SSL_CAPABLE_MORE_SERVICE)
426 				return 0;
427 			if (buffered < 0 || eb.len < 0) {
428 				cce = "read failed";
429 				goto bail3;
430 			}
431 			if (!eb.len)
432 				return 0;
433 
434 			n = eb.len;
435 			if (lws_parse(wsi, eb.token, &n)) {
436 				lwsl_warn("problems parsing header\n");
437 				cce = "problems parsing header";
438 				goto bail3;
439 			}
440 
441 			m = eb.len - n;
442 			if (lws_buflist_aware_finished_consuming(wsi, &eb, m,
443 								 buffered,
444 								 __func__))
445 			        return -1;
446 			eb.token += m;
447 			eb.len -= m;
448 
449 			if (n) {
450 				assert(wsi->http.ah->parser_state ==
451 						WSI_PARSING_COMPLETE);
452 
453 				break;
454 			}
455 		}
456 
457 		/*
458 		 * hs may also be coming in multiple packets, there is a 5-sec
459 		 * libwebsocket timeout still active here too, so if parsing did
460 		 * not complete just wait for next packet coming in this state
461 		 */
462 		if (wsi->http.ah->parser_state != WSI_PARSING_COMPLETE)
463 			break;
464 #endif
465 
466 		/*
467 		 * otherwise deal with the handshake.  If there's any
468 		 * packet traffic already arrived we'll trigger poll() again
469 		 * right away and deal with it that way
470 		 */
471 		return lws_client_interpret_server_handshake(wsi);
472 
473 bail3:
474 		lwsl_info("closing conn at LWS_CONNMODE...SERVER_REPLY\n");
475 		if (cce)
476 			lwsl_info("reason: %s\n", cce);
477 		lws_inform_client_conn_fail(wsi, (void *)cce, strlen(cce));
478 
479 		lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS, "cbail3");
480 		return -1;
481 
482 	default:
483 		break;
484 	}
485 
486 	return 0;
487 }
488 
489 #if defined(LWS_ROLE_H1) || defined(LWS_ROLE_H2)
490 
491 int LWS_WARN_UNUSED_RESULT
lws_http_transaction_completed_client(struct lws * wsi)492 lws_http_transaction_completed_client(struct lws *wsi)
493 {
494 	int n;
495 
496 	lwsl_info("%s: wsi: %p (%s)\n", __func__, wsi, wsi->protocol->name);
497 
498 	if (user_callback_handle_rxflow(wsi->protocol->callback, wsi,
499 					LWS_CALLBACK_COMPLETED_CLIENT_HTTP,
500 					wsi->user_space, NULL, 0)) {
501 		lwsl_debug("%s: Completed call returned nonzero (role 0x%lx)\n",
502 			   __func__, (unsigned long)lwsi_role(wsi));
503 		return -1;
504 	}
505 
506 	wsi->http.rx_content_length = 0;
507 
508 	/*
509 	 * For h1, wsi may pass some assets on to a queued child and be
510 	 * destroyed during this.
511 	 */
512 	n = _lws_generic_transaction_completed_active_conn(&wsi);
513 
514 	if (wsi->http.ah) {
515 		if (wsi->client_mux_substream)
516 			/*
517 			 * As an h2 client, once we did our transaction, that is
518 			 * it for us.  Further transactions will happen as new
519 			 * SIDs on the connection.
520 			 */
521 			__lws_header_table_detach(wsi, 0);
522 		else
523 			if (!n)
524 				_lws_header_table_reset(wsi->http.ah);
525 	}
526 
527 	if (!n || !wsi->http.ah)
528 		return 0;
529 
530 	/*
531 	 * H1: we can serialize the queued guys into the same ah
532 	 * H2: everybody needs their own ah until their own STREAM_END
533 	 */
534 
535 	/* otherwise set ourselves up ready to go again */
536 	lwsi_set_state(wsi, LRS_WAITING_SERVER_REPLY);
537 
538 	wsi->http.ah->parser_state = WSI_TOKEN_NAME_PART;
539 	wsi->http.ah->lextable_pos = 0;
540 #if defined(LWS_WITH_CUSTOM_HEADERS)
541 	wsi->http.ah->unk_pos = 0;
542 #endif
543 
544 	lws_set_timeout(wsi, PENDING_TIMEOUT_AWAITING_SERVER_RESPONSE,
545 			wsi->context->timeout_secs);
546 
547 	/* If we're (re)starting on headers, need other implied init */
548 	wsi->http.ah->ues = URIES_IDLE;
549 	lwsi_set_state(wsi, LRS_H1C_ISSUE_HANDSHAKE2);
550 
551 	lwsl_info("%s: %p: new queued transaction\n", __func__, wsi);
552 	lws_callback_on_writable(wsi);
553 
554 	return 0;
555 }
556 
557 unsigned int
lws_http_client_http_response(struct lws * wsi)558 lws_http_client_http_response(struct lws *wsi)
559 {
560 	if (wsi->http.ah && wsi->http.ah->http_response)
561 		return wsi->http.ah->http_response;
562 
563 	return 0;
564 }
565 #endif
566 
567 #if defined(LWS_ROLE_H1) || defined(LWS_ROLE_H2)
568 
569 int
lws_http_is_redirected_to_get(struct lws * wsi)570 lws_http_is_redirected_to_get(struct lws *wsi)
571 {
572 	return wsi->redirected_to_get;
573 }
574 
575 int
lws_client_interpret_server_handshake(struct lws * wsi)576 lws_client_interpret_server_handshake(struct lws *wsi)
577 {
578 	int n, port = 0, ssl = 0;
579 	int close_reason = LWS_CLOSE_STATUS_PROTOCOL_ERR;
580 	const char *prot, *ads = NULL, *path, *cce = NULL;
581 	struct allocated_headers *ah, *ah1;
582 	struct lws *nwsi = lws_get_network_wsi(wsi);
583 	char *p = NULL, *q;
584 	char new_path[300];
585 
586 	lws_free_set_NULL(wsi->stash);
587 
588 	ah = wsi->http.ah;
589 	if (!wsi->do_ws) {
590 		/* we are being an http client...
591 		 */
592 #if defined(LWS_ROLE_H2)
593 		if (wsi->client_h2_alpn || wsi->client_mux_substream) {
594 			lwsl_debug("%s: %p: transitioning to h2 client\n",
595 				   __func__, wsi);
596 			lws_role_transition(wsi, LWSIFR_CLIENT,
597 					    LRS_ESTABLISHED, &role_ops_h2);
598 		} else
599 #endif
600 		{
601 #if defined(LWS_ROLE_H1)
602 			{
603 			lwsl_debug("%s: %p: transitioning to h1 client\n",
604 				   __func__, wsi);
605 			lws_role_transition(wsi, LWSIFR_CLIENT,
606 					    LRS_ESTABLISHED, &role_ops_h1);
607 			}
608 #else
609 			return -1;
610 #endif
611 		}
612 
613 		wsi->http.ah = ah;
614 		ah->http_response = 0;
615 	}
616 
617 	/*
618 	 * well, what the server sent looked reasonable for syntax.
619 	 * Now let's confirm it sent all the necessary headers
620 	 *
621 	 * http (non-ws) client will expect something like this
622 	 *
623 	 * HTTP/1.0.200
624 	 * server:.libwebsockets
625 	 * content-type:.text/html
626 	 * content-length:.17703
627 	 * set-cookie:.test=LWS_1456736240_336776_COOKIE;Max-Age=360000
628 	 */
629 
630 	wsi->http.conn_type = HTTP_CONNECTION_KEEP_ALIVE;
631 	if (!wsi->client_mux_substream) {
632 		p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP);
633 		/*
634 		if (wsi->do_ws && !p) {
635 			lwsl_info("no URI\n");
636 			cce = "HS: URI missing";
637 			goto bail3;
638 		}
639 		*/
640 		if (!p) {
641 			p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP1_0);
642 			wsi->http.conn_type = HTTP_CONNECTION_CLOSE;
643 		}
644 		if (!p) {
645 			cce = "HS: URI missing";
646 			lwsl_info("no URI\n");
647 			goto bail3;
648 		}
649 #if defined(LWS_ROLE_H2)
650 	} else {
651 		p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP_COLON_STATUS);
652 		if (!p) {
653 			cce = "HS: :status missing";
654 			lwsl_info("no status\n");
655 			goto bail3;
656 		}
657 #endif
658 	}
659 #if !defined(LWS_ROLE_H2)
660 	if (!p) {
661 		cce = "HS: :status missing";
662 		lwsl_info("no status\n");
663 		goto bail3;
664 	}
665 #endif
666 	n = atoi(p);
667 	if (ah)
668 		ah->http_response = n;
669 
670 	if (!wsi->client_no_follow_redirect &&
671 #if defined(LWS_WITH_HTTP_PROXY)
672 	    !wsi->http.proxy_clientside &&
673 #endif
674 	    (n == 301 || n == 302 || n == 303 || n == 307 || n == 308)) {
675 		p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP_LOCATION);
676 		if (!p) {
677 			cce = "HS: Redirect code but no Location";
678 			goto bail3;
679 		}
680 
681 		/*
682 		 * Some redirect codes imply we have to change the method
683 		 * used for the subsequent transaction, commonly POST ->
684 		 * 303 -> GET.
685 		 */
686 
687 		if (n == 303) {
688 			char *mp = lws_hdr_simple_ptr(wsi,_WSI_TOKEN_CLIENT_METHOD);
689 			int ml = lws_hdr_total_length(wsi, _WSI_TOKEN_CLIENT_METHOD);
690 
691 			if (ml >= 3 && mp) {
692 				lwsl_info("%s: 303 switching to GET\n", __func__);
693 				memcpy(mp, "GET", 4);
694 				wsi->redirected_to_get = 1;
695 				wsi->http.ah->frags[wsi->http.ah->frag_index[
696 				             _WSI_TOKEN_CLIENT_METHOD]].len = 3;
697 			}
698 		}
699 
700 		/* Relative reference absolute path */
701 		if (p[0] == '/' || !strchr(p, ':')) {
702 #if defined(LWS_WITH_TLS)
703 			ssl = nwsi->tls.use_ssl & LCCSCF_USE_SSL;
704 #endif
705 			ads = lws_hdr_simple_ptr(wsi,
706 						 _WSI_TOKEN_CLIENT_PEER_ADDRESS);
707 			port = nwsi->c_port;
708 			path = p;
709 			/* lws_client_reset expects leading / omitted */
710 			if (*path == '/')
711 				path++;
712 		}
713 		/* Absolute (Full) URI */
714 		else if (strchr(p, ':')) {
715 			if (lws_parse_uri(p, &prot, &ads, &port, &path)) {
716 				cce = "HS: URI did not parse";
717 				goto bail3;
718 			}
719 
720 			if (!strcmp(prot, "wss") || !strcmp(prot, "https"))
721 				ssl = LCCSCF_USE_SSL;
722 		}
723 		/* Relative reference relative path */
724 		else {
725 			/* This doesn't try to calculate an absolute path,
726 			 * that will be left to the server */
727 #if defined(LWS_WITH_TLS)
728 			ssl = nwsi->tls.use_ssl & LCCSCF_USE_SSL;
729 #endif
730 			ads = lws_hdr_simple_ptr(wsi,
731 						 _WSI_TOKEN_CLIENT_PEER_ADDRESS);
732 			port = wsi->c_port;
733 			/* +1 as lws_client_reset expects leading / omitted */
734 			path = new_path + 1;
735 			if (lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_URI))
736 				lws_strncpy(new_path, lws_hdr_simple_ptr(wsi,
737 				   _WSI_TOKEN_CLIENT_URI), sizeof(new_path));
738 			else {
739 				new_path[0] = '/';
740 				new_path[1] = '\0';
741 			}
742 			q = strrchr(new_path, '/');
743 			if (q)
744 				lws_strncpy(q + 1, p, sizeof(new_path) -
745 							(q - new_path) - 1);
746 			else
747 				path = p;
748 		}
749 
750 #if defined(LWS_WITH_TLS)
751 		if ((wsi->tls.use_ssl & LCCSCF_USE_SSL) && !ssl) {
752 			cce = "HS: Redirect attempted SSL downgrade";
753 			goto bail3;
754 		}
755 #endif
756 
757 		if (!ads) /* make coverity happy */ {
758 			cce = "no ads";
759 			goto bail3;
760 		}
761 
762 		if (!lws_client_reset(&wsi, ssl, ads, port, path, ads, 1)) {
763 			/*
764 			 * There are two ways to fail out with NULL return...
765 			 * simple, early problem where the wsi is intact, or
766 			 * we went through with the reconnect attempt and the
767 			 * wsi is already closed.  In the latter case, the wsi
768 			 * has been set to NULL additionally.
769 			 */
770 			lwsl_err("Redirect failed\n");
771 			cce = "HS: Redirect failed";
772 			/* coverity[reverse_inull] */
773 			if (wsi)
774 				goto bail3;
775 
776 			/* wsi has closed */
777 			return 1;
778 		}
779 		return 0;
780 	}
781 
782 	if (!wsi->do_ws) {
783 
784 		/* if h1 KA is allowed, enable the queued pipeline guys */
785 
786 		if (!wsi->client_h2_alpn && !wsi->client_mux_substream) {
787 			/* ie, coming to this for the first time */
788 			if (wsi->http.conn_type == HTTP_CONNECTION_KEEP_ALIVE)
789 				wsi->keepalive_active = 1;
790 			else {
791 				/*
792 				 * Ugh... now the main http connection has seen
793 				 * both sides, we learn the server doesn't
794 				 * support keepalive.
795 				 *
796 				 * That means any guys queued on us are going
797 				 * to have to be restarted from connect2 with
798 				 * their own connections.
799 				 */
800 
801 				/*
802 				 * stick around telling any new guys they can't
803 				 * pipeline to this server
804 				 */
805 				wsi->keepalive_rejected = 1;
806 
807 				lws_vhost_lock(wsi->vhost);
808 				lws_start_foreach_dll_safe(struct lws_dll2 *,
809 							   d, d1,
810 				  wsi->dll2_cli_txn_queue_owner.head) {
811 					struct lws *ww = lws_container_of(d,
812 						struct lws,
813 						dll2_cli_txn_queue);
814 
815 					/* remove him from our queue */
816 					lws_dll2_remove(&ww->dll2_cli_txn_queue);
817 					/* give up on pipelining */
818 					ww->client_pipeline = 0;
819 
820 					/* go back to "trying to connect" state */
821 					lws_role_transition(ww, LWSIFR_CLIENT,
822 							    LRS_UNCONNECTED,
823 #if defined(LWS_ROLE_H1)
824 							    &role_ops_h1);
825 #else
826 #if defined (LWS_ROLE_H2)
827 							    &role_ops_h2);
828 #else
829 							    &role_ops_raw);
830 #endif
831 #endif
832 					ww->user_space = NULL;
833 				} lws_end_foreach_dll_safe(d, d1);
834 				lws_vhost_unlock(wsi->vhost);
835 			}
836 		}
837 
838 #ifdef LWS_WITH_HTTP_PROXY
839 		wsi->http.perform_rewrite = 0;
840 		if (lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_CONTENT_TYPE)) {
841 			if (!strncmp(lws_hdr_simple_ptr(wsi,
842 						WSI_TOKEN_HTTP_CONTENT_TYPE),
843 						"text/html", 9))
844 				wsi->http.perform_rewrite = 0;
845 		}
846 #endif
847 
848 		/* allocate the per-connection user memory (if any) */
849 		if (lws_ensure_user_space(wsi)) {
850 			lwsl_err("Problem allocating wsi user mem\n");
851 			cce = "HS: OOM";
852 			goto bail2;
853 		}
854 
855 		/* he may choose to send us stuff in chunked transfer-coding */
856 		wsi->chunked = 0;
857 		wsi->chunk_remaining = 0; /* ie, next thing is chunk size */
858 		if (lws_hdr_total_length(wsi,
859 					WSI_TOKEN_HTTP_TRANSFER_ENCODING)) {
860 			wsi->chunked = !strcmp(lws_hdr_simple_ptr(wsi,
861 					       WSI_TOKEN_HTTP_TRANSFER_ENCODING),
862 						"chunked");
863 			/* first thing is hex, after payload there is crlf */
864 			wsi->chunk_parser = ELCP_HEX;
865 		}
866 
867 		wsi->http.content_length_given = 0;
868 		if (lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_CONTENT_LENGTH)) {
869 			wsi->http.rx_content_length =
870 					atoll(lws_hdr_simple_ptr(wsi,
871 						WSI_TOKEN_HTTP_CONTENT_LENGTH));
872 			lwsl_info("%s: incoming content length %llu\n",
873 				    __func__, (unsigned long long)
874 					    wsi->http.rx_content_length);
875 			wsi->http.rx_content_remain =
876 					wsi->http.rx_content_length;
877 			wsi->http.content_length_given = 1;
878 		} else { /* can't do 1.1 without a content length or chunked */
879 			if (!wsi->chunked)
880 				wsi->http.conn_type = HTTP_CONNECTION_CLOSE;
881 			lwsl_debug("%s: no content length\n", __func__);
882 		}
883 
884 		/*
885 		 * we seem to be good to go, give client last chance to check
886 		 * headers and OK it
887 		 */
888 		ah1 = wsi->http.ah;
889 		wsi->http.ah = ah;
890 		if (wsi->protocol->callback(wsi,
891 				LWS_CALLBACK_CLIENT_FILTER_PRE_ESTABLISH,
892 					    wsi->user_space, NULL, 0)) {
893 			wsi->http.ah = ah1;
894 			cce = "HS: disallowed by client filter";
895 			goto bail2;
896 		}
897 
898 		/* clear his proxy connection timeout */
899 		lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
900 
901 		wsi->rxflow_change_to = LWS_RXFLOW_ALLOW;
902 
903 		/* call him back to inform him he is up */
904 		if (wsi->protocol->callback(wsi,
905 					    LWS_CALLBACK_ESTABLISHED_CLIENT_HTTP,
906 					    wsi->user_space, NULL, 0)) {
907 			wsi->http.ah = ah1;
908 			cce = "HS: disallowed at ESTABLISHED";
909 			goto bail3;
910 		}
911 
912 		wsi->http.ah = ah1;
913 
914 		lwsl_info("%s: client connection up\n", __func__);
915 
916 		/*
917 		 * Did we get a response from the server with an explicit
918 		 * content-length of zero?  If so, this transaction is already
919 		 * completed at the end of the header processing...
920 		 */
921 		if (lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_CONTENT_LENGTH) &&
922 		    !wsi->http.rx_content_length)
923 		        return !!lws_http_transaction_completed_client(wsi);
924 
925 		return 0;
926 	}
927 
928 #if defined(LWS_ROLE_WS)
929 	switch (lws_client_ws_upgrade(wsi, &cce)) {
930 	case 2:
931 		goto bail2;
932 	case 3:
933 		goto bail3;
934 	}
935 
936 	return 0;
937 #endif
938 
939 bail3:
940 	close_reason = LWS_CLOSE_STATUS_NOSTATUS;
941 
942 bail2:
943 	if (wsi->protocol) {
944 		n = 0;
945 		if (cce)
946 			n = (int)strlen(cce);
947 
948 		lws_inform_client_conn_fail(wsi, (void *)cce, (unsigned int)n);
949 	}
950 
951 	lwsl_info("closing connection (prot %s) "
952 		  "due to bail2 connection error: %s\n", wsi->protocol ?
953 				  wsi->protocol->name : "unknown", cce);
954 
955 	/* closing will free up his parsing allocations */
956 	lws_close_free_wsi(wsi, close_reason, "c hs interp");
957 
958 	return 1;
959 }
960 #endif
961 
962 /*
963  * set the boundary string and the content-type for client multipart mime
964  */
965 
966 uint8_t *
lws_http_multipart_headers(struct lws * wsi,uint8_t * p)967 lws_http_multipart_headers(struct lws *wsi, uint8_t *p)
968 {
969 	char buf[10], arg[48];
970 	int n;
971 
972 	lws_get_random(wsi->context, (uint8_t *)buf, sizeof(buf));
973 	lws_b64_encode_string(buf, sizeof(buf),
974 			       wsi->http.multipart_boundary,
975 			       sizeof(wsi->http.multipart_boundary));
976 
977 	n = lws_snprintf(arg, sizeof(arg), "multipart/form-data; boundary=%s",
978 			 wsi->http.multipart_boundary);
979 
980 	if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_CONTENT_TYPE,
981 					 (uint8_t *)arg, n, &p, p + 100))
982 		return NULL;
983 
984 	wsi->http.multipart = wsi->http.multipart_issue_boundary = 1;
985 	lws_client_http_body_pending(wsi, 1);
986 
987 	return p;
988 }
989 
990 int
lws_client_http_multipart(struct lws * wsi,const char * name,const char * filename,const char * content_type,char ** p,char * end)991 lws_client_http_multipart(struct lws *wsi, const char *name,
992 			  const char *filename, const char *content_type,
993 			  char **p, char *end)
994 {
995 	/*
996 	 * Client conn must have been created with LCCSCF_HTTP_MULTIPART_MIME
997 	 * flag to use this api
998 	 */
999 	assert(wsi->http.multipart);
1000 
1001 	if (!name) {
1002 		*p += lws_snprintf((char *)(*p), lws_ptr_diff(end, p),
1003 					"\xd\xa--%s--\xd\xa",
1004 					wsi->http.multipart_boundary);
1005 
1006 		return 0;
1007 	}
1008 
1009 	if (wsi->client_subsequent_mime_part)
1010 		*p += lws_snprintf((char *)(*p), lws_ptr_diff(end, p), "\xd\xa");
1011 	wsi->client_subsequent_mime_part = 1;
1012 
1013 	*p += lws_snprintf((char *)(*p), lws_ptr_diff(end, p), "--%s\xd\xa"
1014 				    "Content-Disposition: form-data; "
1015 				      "name=\"%s\"",
1016 				      wsi->http.multipart_boundary, name);
1017 	if (filename)
1018 		*p += lws_snprintf((char *)(*p), lws_ptr_diff(end, p),
1019 				   "; filename=\"%s\"", filename);
1020 
1021 	if (content_type)
1022 		*p += lws_snprintf((char *)(*p), lws_ptr_diff(end, p), "\xd\xa"
1023 				"Content-Type: %s", content_type);
1024 
1025 	*p += lws_snprintf((char *)(*p), lws_ptr_diff(end, p), "\xd\xa\xd\xa");
1026 
1027 	return *p == end;
1028 }
1029 
1030 char *
lws_generate_client_handshake(struct lws * wsi,char * pkt)1031 lws_generate_client_handshake(struct lws *wsi, char *pkt)
1032 {
1033 	const char *meth, *pp = lws_hdr_simple_ptr(wsi,
1034 				_WSI_TOKEN_CLIENT_SENT_PROTOCOLS);
1035 	char *p = pkt, *p1;
1036 
1037 	meth = lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_METHOD);
1038 	if (!meth) {
1039 		meth = "GET";
1040 		wsi->do_ws = 1;
1041 	} else {
1042 		wsi->do_ws = 0;
1043 	}
1044 
1045 	if (!strcmp(meth, "RAW")) {
1046 		lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
1047 		lwsl_notice("client transition to raw\n");
1048 
1049 		if (pp) {
1050 			const struct lws_protocols *pr;
1051 
1052 			pr = lws_vhost_name_to_protocol(wsi->vhost, pp);
1053 
1054 			if (!pr) {
1055 				lwsl_err("protocol %s not enabled on vhost\n",
1056 					 pp);
1057 				return NULL;
1058 			}
1059 
1060 			lws_bind_protocol(wsi, pr, __func__);
1061 		}
1062 
1063 		if ((wsi->protocol->callback)(wsi, LWS_CALLBACK_RAW_ADOPT,
1064 					      wsi->user_space, NULL, 0))
1065 			return NULL;
1066 
1067 		lws_role_transition(wsi, LWSIFR_CLIENT, LRS_ESTABLISHED,
1068 				    &role_ops_raw_skt);
1069 		lws_header_table_detach(wsi, 1);
1070 
1071 		return NULL;
1072 	}
1073 
1074 	/*
1075 	 * 04 example client handshake
1076 	 *
1077 	 * GET /chat HTTP/1.1
1078 	 * Host: server.example.com
1079 	 * Upgrade: websocket
1080 	 * Connection: Upgrade
1081 	 * Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==
1082 	 * Sec-WebSocket-Origin: http://example.com
1083 	 * Sec-WebSocket-Protocol: chat, superchat
1084 	 * Sec-WebSocket-Version: 4
1085 	 */
1086 
1087 	p += lws_snprintf(p, 2048, "%s %s HTTP/1.1\x0d\x0a", meth,
1088 		     lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_URI));
1089 
1090 	p += lws_snprintf(p, 64, "Pragma: no-cache\x0d\x0a"
1091 			"Cache-Control: no-cache\x0d\x0a");
1092 
1093 	p += lws_snprintf(p, 128, "Host: %s\x0d\x0a",
1094 		     lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_HOST));
1095 
1096 	if (lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_ORIGIN)) {
1097 		if (lws_check_opt(wsi->context->options,
1098 				  LWS_SERVER_OPTION_JUST_USE_RAW_ORIGIN))
1099 			p += lws_snprintf(p, 128, "Origin: %s\x0d\x0a",
1100 				     lws_hdr_simple_ptr(wsi,
1101 						     _WSI_TOKEN_CLIENT_ORIGIN));
1102 		else
1103 			p += lws_snprintf(p, 128, "Origin: http://%s\x0d\x0a",
1104 				     lws_hdr_simple_ptr(wsi,
1105 						     _WSI_TOKEN_CLIENT_ORIGIN));
1106 	}
1107 
1108 	if (wsi->flags & LCCSCF_HTTP_MULTIPART_MIME) {
1109 		p1 = (char *)lws_http_multipart_headers(wsi, (uint8_t *)p);
1110 		if (!p1)
1111 			return NULL;
1112 		p = p1;
1113 	}
1114 
1115 #if defined(LWS_WITH_HTTP_PROXY)
1116 	if (wsi->parent &&
1117 	    lws_hdr_total_length(wsi->parent, WSI_TOKEN_HTTP_CONTENT_LENGTH)) {
1118 		p += lws_snprintf(p, 128, "Content-Length: %s\x0d\x0a",
1119 			lws_hdr_simple_ptr(wsi->parent, WSI_TOKEN_HTTP_CONTENT_LENGTH));
1120 		if (atoi(lws_hdr_simple_ptr(wsi->parent, WSI_TOKEN_HTTP_CONTENT_LENGTH)))
1121 			wsi->client_http_body_pending = 1;
1122 	}
1123 	if (wsi->parent &&
1124 	    lws_hdr_total_length(wsi->parent, WSI_TOKEN_HTTP_AUTHORIZATION)) {
1125 		p += lws_snprintf(p, 128, "Authorization: %s\x0d\x0a",
1126 			lws_hdr_simple_ptr(wsi->parent, WSI_TOKEN_HTTP_AUTHORIZATION));
1127 	}
1128 	if (wsi->parent &&
1129 	    lws_hdr_total_length(wsi->parent, WSI_TOKEN_HTTP_CONTENT_TYPE)) {
1130 		p += lws_snprintf(p, 128, "Content-Type: %s\x0d\x0a",
1131 			lws_hdr_simple_ptr(wsi->parent, WSI_TOKEN_HTTP_CONTENT_TYPE));
1132 	}
1133 #endif
1134 
1135 #if defined(LWS_ROLE_WS)
1136 	if (wsi->do_ws) {
1137 		const char *conn1 = "";
1138 	//	if (!wsi->client_pipeline)
1139 	//		conn1 = "close, ";
1140 		p = lws_generate_client_ws_handshake(wsi, p, conn1);
1141 	} else
1142 #endif
1143 	{
1144 		if (!wsi->client_pipeline)
1145 			p += lws_snprintf(p, 64, "connection: close\x0d\x0a");
1146 	}
1147 
1148 	/* give userland a chance to append, eg, cookies */
1149 
1150 	if (wsi->protocol->callback(wsi,
1151 			LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER,
1152 			wsi->user_space, &p,
1153 			(pkt + wsi->context->pt_serv_buf_size) - p - 12))
1154 		return NULL;
1155 
1156 	if (wsi->flags & LCCSCF_HTTP_X_WWW_FORM_URLENCODED) {
1157 		p += lws_snprintf(p, 128, "Content-Type: application/x-www-form-urlencoded\x0d\x0a");
1158 		p += lws_snprintf(p, 128, "Content-Length: %lu\x0d\x0a", wsi->http.writeable_len);
1159 		lws_client_http_body_pending(wsi, 1);
1160 	}
1161 
1162 	p += lws_snprintf(p, 4, "\x0d\x0a");
1163 
1164 	if (wsi->client_http_body_pending)
1165 		lws_callback_on_writable(wsi);
1166 
1167 	// puts(pkt);
1168 
1169 	return p;
1170 }
1171 
1172 #if defined(LWS_ROLE_H1) || defined(LWS_ROLE_H2)
1173 #if defined(LWS_WITH_HTTP_BASIC_AUTH)
1174 
1175 int
lws_http_basic_auth_gen(const char * user,const char * pw,char * buf,size_t len)1176 lws_http_basic_auth_gen(const char *user, const char *pw, char *buf, size_t len)
1177 {
1178 	size_t n = strlen(user), m = strlen(pw);
1179 	char b[128];
1180 
1181 	if (len < 6 + ((4 * (n + m + 1)) / 3) + 1)
1182 		return 1;
1183 
1184 	memcpy(buf, "Basic ", 6);
1185 
1186 	n = lws_snprintf(b, sizeof(b), "%s:%s", user, pw);
1187 	if (n >= sizeof(b) - 2)
1188 		return 2;
1189 
1190 	lws_b64_encode_string(b, (int)n, buf + 6, (int)len - 6);
1191 	buf[len - 1] = '\0';
1192 
1193 	return 0;
1194 }
1195 
1196 #endif
1197 
1198 int
lws_http_client_read(struct lws * wsi,char ** buf,int * len)1199 lws_http_client_read(struct lws *wsi, char **buf, int *len)
1200 {
1201 	struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
1202 	struct lws_tokens eb;
1203 	int buffered, n, consumed = 0;
1204 
1205 	/*
1206 	 * If the caller provided a non-NULL *buf and nonzero *len, we should
1207 	 * use that as the buffer for the read action, limititing it to *len
1208 	 * (actual payload will be less if chunked headers inside).
1209 	 *
1210 	 * If it's NULL / 0 length, buflist_aware_read will use the pt_serv_buf
1211 	 */
1212 
1213 	eb.token = (unsigned char *)*buf;
1214 	eb.len = *len;
1215 
1216 	buffered = lws_buflist_aware_read(pt, wsi, &eb, 0, __func__);
1217 	*buf = (char *)eb.token; /* may be pointing to buflist or pt_serv_buf */
1218 	*len = 0;
1219 
1220 	/*
1221 	 * we're taking on responsibility for handling used / unused eb
1222 	 * when we leave, via lws_buflist_aware_finished_consuming()
1223 	 */
1224 
1225 //	lwsl_notice("%s: eb.len %d ENTRY chunk remaining %d\n", __func__, eb.len,
1226 //			wsi->chunk_remaining);
1227 
1228 	/* allow the source to signal he has data again next time */
1229 	if (lws_change_pollfd(wsi, 0, LWS_POLLIN))
1230 		return -1;
1231 
1232 	if (buffered < 0) {
1233 		lwsl_debug("%s: SSL capable error\n", __func__);
1234 		return -1;
1235 	}
1236 
1237 	if (eb.len <= 0)
1238 		return 0;
1239 
1240 	*len = eb.len;
1241 	wsi->client_rx_avail = 0;
1242 
1243 	/*
1244 	 * server may insist on transfer-encoding: chunked,
1245 	 * so http client must deal with it
1246 	 */
1247 spin_chunks:
1248 	//lwsl_notice("%s: len %d SPIN chunk remaining %d\n", __func__, *len,
1249 	//		wsi->chunk_remaining);
1250 	while (wsi->chunked && (wsi->chunk_parser != ELCP_CONTENT) && *len) {
1251 		switch (wsi->chunk_parser) {
1252 		case ELCP_HEX:
1253 			if ((*buf)[0] == '\x0d') {
1254 				wsi->chunk_parser = ELCP_CR;
1255 				break;
1256 			}
1257 			n = char_to_hex((*buf)[0]);
1258 			if (n < 0) {
1259 				lwsl_err("%s: chunking failure A\n", __func__);
1260 				return -1;
1261 			}
1262 			wsi->chunk_remaining <<= 4;
1263 			wsi->chunk_remaining |= n;
1264 			break;
1265 		case ELCP_CR:
1266 			if ((*buf)[0] != '\x0a') {
1267 				lwsl_err("%s: chunking failure B\n", __func__);
1268 				return -1;
1269 			}
1270 			if (wsi->chunk_remaining) {
1271 				wsi->chunk_parser = ELCP_CONTENT;
1272 				//lwsl_notice("starting chunk size %d (block rem %d)\n",
1273 				//		wsi->chunk_remaining, *len);
1274 				break;
1275 			}
1276 
1277 			wsi->chunk_parser = ELCP_TRAILER_CR;
1278 			break;
1279 
1280 		case ELCP_CONTENT:
1281 			break;
1282 
1283 		case ELCP_POST_CR:
1284 			if ((*buf)[0] != '\x0d') {
1285 				lwsl_err("%s: chunking failure C\n", __func__);
1286 				lwsl_hexdump_err(*buf, *len);
1287 
1288 				return -1;
1289 			}
1290 
1291 			wsi->chunk_parser = ELCP_POST_LF;
1292 			break;
1293 
1294 		case ELCP_POST_LF:
1295 			if ((*buf)[0] != '\x0a') {
1296 				lwsl_err("%s: chunking failure D\n", __func__);
1297 
1298 				return -1;
1299 			}
1300 
1301 			wsi->chunk_parser = ELCP_HEX;
1302 			wsi->chunk_remaining = 0;
1303 			break;
1304 
1305 		case ELCP_TRAILER_CR:
1306 			if ((*buf)[0] != '\x0d') {
1307 				lwsl_err("%s: chunking failure F\n", __func__);
1308 				lwsl_hexdump_err(*buf, *len);
1309 
1310 				return -1;
1311 			}
1312 
1313 			wsi->chunk_parser = ELCP_TRAILER_LF;
1314 			break;
1315 
1316 		case ELCP_TRAILER_LF:
1317 			if ((*buf)[0] != '\x0a') {
1318 				lwsl_err("%s: chunking failure F\n", __func__);
1319 				lwsl_hexdump_err(*buf, *len);
1320 
1321 				return -1;
1322 			}
1323 
1324 			(*buf)++;
1325 			(*len)--;
1326 			consumed++;
1327 
1328 			lwsl_info("final chunk\n");
1329 			goto completed;
1330 		}
1331 		(*buf)++;
1332 		(*len)--;
1333 		consumed++;
1334 	}
1335 
1336 	if (wsi->chunked && !wsi->chunk_remaining)
1337 		goto account_and_ret;
1338 
1339 	if (wsi->http.rx_content_remain &&
1340 	    wsi->http.rx_content_remain < (unsigned int)*len)
1341 		n = (int)wsi->http.rx_content_remain;
1342 	else
1343 		n = *len;
1344 
1345 	if (wsi->chunked && wsi->chunk_remaining &&
1346 	    wsi->chunk_remaining < n)
1347 		n = wsi->chunk_remaining;
1348 
1349 #if defined(LWS_WITH_HTTP_PROXY) && defined(LWS_WITH_HUBBUB)
1350 	/* hubbub */
1351 	if (wsi->http.perform_rewrite)
1352 		lws_rewrite_parse(wsi->http.rw, (unsigned char *)*buf, n);
1353 	else
1354 #endif
1355 	{
1356 		if (
1357 #if defined(LWS_WITH_HTTP_PROXY)
1358 		    !wsi->protocol_bind_balance ==
1359 		    !!wsi->http.proxy_clientside
1360 #else
1361 		    !!wsi->protocol_bind_balance
1362 #endif
1363 		  ) {
1364 			if (user_callback_handle_rxflow(wsi->protocol->callback,
1365 				wsi, LWS_CALLBACK_RECEIVE_CLIENT_HTTP_READ,
1366 				wsi->user_space, *buf, n)) {
1367 				lwsl_info("%s: RECEIVE_CLIENT_HTTP_READ returned -1\n",
1368 						__func__);
1369 
1370 				return -1;
1371 			}
1372 		} else
1373 			lwsl_notice("%s: swallowed read (%d)\n", __func__, n);
1374 	}
1375 
1376 	(*buf) += n;
1377 	*len -= n;
1378 	if (wsi->chunked && wsi->chunk_remaining)
1379 		wsi->chunk_remaining -= n;
1380 
1381 	//lwsl_notice("chunk_remaining <- %d, block remaining %d\n",
1382 	//		wsi->chunk_remaining, *len);
1383 
1384 	consumed += n;
1385 	//eb.token += n;
1386 	//eb.len -= n;
1387 
1388 	if (wsi->chunked && !wsi->chunk_remaining)
1389 		wsi->chunk_parser = ELCP_POST_CR;
1390 
1391 	if (wsi->chunked && *len)
1392 		goto spin_chunks;
1393 
1394 	if (wsi->chunked)
1395 		goto account_and_ret;
1396 
1397 	/* if we know the content length, decrement the content remaining */
1398 	if (wsi->http.rx_content_length > 0)
1399 		wsi->http.rx_content_remain -= n;
1400 
1401 	// lwsl_notice("rx_content_remain %lld, rx_content_length %lld, giv %d\n",
1402 	//	    wsi->http.rx_content_remain, wsi->http.rx_content_length,
1403 	//	    wsi->http.content_length_given);
1404 
1405 	if (wsi->http.rx_content_remain || !wsi->http.content_length_given)
1406 		goto account_and_ret;
1407 
1408 completed:
1409 
1410 	if (lws_http_transaction_completed_client(wsi)) {
1411 		lwsl_notice("%s: transaction completed says -1\n", __func__);
1412 		return -1;
1413 	}
1414 
1415 account_and_ret:
1416 //	lwsl_warn("%s: on way out, consuming %d / %d\n", __func__, consumed, eb.len);
1417 	if (lws_buflist_aware_finished_consuming(wsi, &eb, consumed, buffered,
1418 							__func__))
1419 		return -1;
1420 
1421 	return 0;
1422 }
1423 
1424 #endif
1425