1 /*
2 * libwebsockets - small server side websockets and web server implementation
3 *
4 * Copyright (C) 2010 - 2019 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 /*
28 * notice this returns number of bytes consumed, or -1
29 */
30 int
lws_issue_raw(struct lws * wsi,unsigned char * buf,size_t len)31 lws_issue_raw(struct lws *wsi, unsigned char *buf, size_t len)
32 {
33 struct lws_context *context = lws_get_context(wsi);
34 struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
35 size_t real_len = len;
36 unsigned int n, m;
37
38 // lwsl_notice("%s: len %d\n", __func__, (int)len);
39 // lwsl_hexdump_level(LLL_NOTICE, buf, len);
40
41 /*
42 * Detect if we got called twice without going through the
43 * event loop to handle pending. Since that guarantees extending any
44 * existing buflist_out it's inefficient.
45 */
46 if (0 && buf && wsi->could_have_pending) {
47 lwsl_hexdump_level(LLL_INFO, buf, len);
48 lwsl_info("** %p: vh: %s, prot: %s, role %s: "
49 "Inefficient back-to-back write of %lu detected...\n",
50 wsi, wsi->vhost ? wsi->vhost->name : "no vhost",
51 wsi->protocol->name, wsi->role_ops->name,
52 (unsigned long)len);
53 }
54
55 lws_stats_bump(pt, LWSSTATS_C_API_WRITE, 1);
56
57 /* just ignore sends after we cleared the truncation buffer */
58 if (lwsi_state(wsi) == LRS_FLUSHING_BEFORE_CLOSE &&
59 !lws_has_buffered_out(wsi)
60 #if defined(LWS_WITH_HTTP_STREAM_COMPRESSION)
61 && !wsi->http.comp_ctx.may_have_more
62 #endif
63 )
64 return (int)len;
65
66 if (buf && lws_has_buffered_out(wsi)) {
67 lwsl_info("** %p: vh: %s, prot: %s, incr buflist_out by %lu\n",
68 wsi, wsi->vhost ? wsi->vhost->name : "no vhost",
69 wsi->protocol->name, (unsigned long)len);
70
71 /*
72 * already buflist ahead of this, add it on the tail of the
73 * buflist, then ignore it for now and act like we're flushing
74 * the buflist...
75 */
76
77 if (lws_buflist_append_segment(&wsi->buflist_out, buf, len))
78 return -1;
79
80 buf = NULL;
81 len = 0;
82 }
83
84 if (wsi->buflist_out) {
85 /* we have to drain the earliest buflist_out stuff first */
86
87 len = lws_buflist_next_segment_len(&wsi->buflist_out, &buf);
88 real_len = len;
89
90 lwsl_debug("%s: draining %d\n", __func__, (int)len);
91 }
92
93 if (!len || !buf)
94 return 0;
95
96 if (!wsi->mux_substream && !lws_socket_is_valid(wsi->desc.sockfd))
97 lwsl_err("%s: invalid sock %p\n", __func__, wsi);
98
99 /* limit sending */
100 if (wsi->protocol->tx_packet_size)
101 n = (int)wsi->protocol->tx_packet_size;
102 else {
103 n = (int)wsi->protocol->rx_buffer_size;
104 if (!n)
105 n = context->pt_serv_buf_size;
106 }
107 n += LWS_PRE + 4;
108 if (n > len)
109 n = (int)len;
110
111 /* nope, send it on the socket directly */
112
113 m = lws_ssl_capable_write(wsi, buf, n);
114 lwsl_info("%s: ssl_capable_write (%d) says %d\n", __func__, n, m);
115
116 /* something got written, it can have been truncated now */
117 wsi->could_have_pending = 1;
118
119 switch (m) {
120 case LWS_SSL_CAPABLE_ERROR:
121 /* we're going to close, let close know sends aren't possible */
122 wsi->socket_is_permanently_unusable = 1;
123 return -1;
124 case LWS_SSL_CAPABLE_MORE_SERVICE:
125 /*
126 * nothing got sent, not fatal. Retry the whole thing later,
127 * ie, implying treat it was a truncated send so it gets
128 * retried
129 */
130 m = 0;
131 break;
132 }
133
134 if ((int)m < 0)
135 m = 0;
136
137 /*
138 * we were sending this from buflist_out? Then not sending everything
139 * is a small matter of advancing ourselves only by the amount we did
140 * send in the buflist.
141 */
142 if (lws_has_buffered_out(wsi)) {
143 if (m) {
144 lwsl_info("%p partial adv %d (vs %ld)\n", wsi, m,
145 (long)real_len);
146 lws_buflist_use_segment(&wsi->buflist_out, m);
147 }
148
149 if (!lws_has_buffered_out(wsi)) {
150 lwsl_info("%s: wsi %p: buflist_out flushed\n",
151 __func__, wsi);
152
153 m = (int)real_len;
154 if (lwsi_state(wsi) == LRS_FLUSHING_BEFORE_CLOSE) {
155 lwsl_info("*%p signalling to close now\n", wsi);
156 return -1; /* retry closing now */
157 }
158
159 if (wsi->close_when_buffered_out_drained) {
160 wsi->close_when_buffered_out_drained = 0;
161 return -1;
162 }
163
164 #if defined(LWS_ROLE_H1) || defined(LWS_ROLE_H2)
165 #if defined(LWS_WITH_SERVER)
166 if (wsi->http.deferred_transaction_completed) {
167 lwsl_notice("%s: partial completed, doing "
168 "deferred transaction completed\n",
169 __func__);
170 wsi->http.deferred_transaction_completed = 0;
171 return lws_http_transaction_completed(wsi) ?
172 -1 : (int)real_len;
173 }
174 #endif
175 #endif
176 #if defined(LWS_ROLE_WS)
177 /* Since buflist_out flushed, we're not inside a frame any more */
178 if (wsi->ws)
179 wsi->ws->inside_frame = 0;
180 #endif
181 }
182 /* always callback on writeable */
183 lws_callback_on_writable(wsi);
184
185 return m;
186 }
187
188 #if defined(LWS_WITH_HTTP_STREAM_COMPRESSION)
189 if (wsi->http.comp_ctx.may_have_more)
190 lws_callback_on_writable(wsi);
191 #endif
192
193 if (m == real_len)
194 /* what we just sent went out cleanly */
195 return m;
196
197 /*
198 * We were not able to send everything... and we were not sending from
199 * an existing buflist_out. So we are starting a fresh buflist_out, by
200 * buffering the unsent remainder on it.
201 * (it will get first priority next time the socket is writable).
202 */
203 lwsl_debug("%p new partial sent %d from %lu total\n", wsi, m,
204 (unsigned long)real_len);
205
206 if (lws_buflist_append_segment(&wsi->buflist_out, buf + m,
207 real_len - m) < 0)
208 return -1;
209
210 lws_stats_bump(pt, LWSSTATS_C_WRITE_PARTIALS, 1);
211 lws_stats_bump(pt, LWSSTATS_B_PARTIALS_ACCEPTED_PARTS, m);
212
213 #if defined(LWS_WITH_UDP)
214 if (lws_wsi_is_udp(wsi)) {
215 /* stash original destination for fulfilling UDP partials */
216 wsi->udp->sa_pending = wsi->udp->sa;
217 wsi->udp->salen_pending = wsi->udp->salen;
218 }
219 #endif
220
221 /* since something buffered, force it to get another chance to send */
222 lws_callback_on_writable(wsi);
223
224 return (int)real_len;
225 }
226
227 int
lws_write(struct lws * wsi,unsigned char * buf,size_t len,enum lws_write_protocol wp)228 lws_write(struct lws *wsi, unsigned char *buf, size_t len,
229 enum lws_write_protocol wp)
230 {
231 struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
232 #if defined(LWS_WITH_DETAILED_LATENCY)
233 lws_usec_t us;
234 #endif
235 int m;
236
237 lws_stats_bump(pt, LWSSTATS_C_API_LWS_WRITE, 1);
238
239 if ((int)len < 0) {
240 lwsl_err("%s: suspicious len int %d, ulong %lu\n", __func__,
241 (int)len, (unsigned long)len);
242 return -1;
243 }
244
245 lws_stats_bump(pt, LWSSTATS_B_WRITE, len);
246
247 #ifdef LWS_WITH_ACCESS_LOG
248 wsi->http.access_log.sent += len;
249 #endif
250 #if defined(LWS_WITH_SERVER_STATUS)
251 if (wsi->vhost)
252 wsi->vhost->conn_stats.tx += len;
253 #endif
254 #if defined(LWS_WITH_DETAILED_LATENCY)
255 us = lws_now_usecs();
256 #endif
257
258 assert(wsi->role_ops);
259 if (!wsi->role_ops->write_role_protocol)
260 return lws_issue_raw(wsi, buf, len);
261
262 m = wsi->role_ops->write_role_protocol(wsi, buf, len, &wp);
263 if (m < 0)
264 return m;
265
266 #if defined(LWS_WITH_DETAILED_LATENCY)
267 if (wsi->context->detailed_latency_cb) {
268 wsi->detlat.req_size = len;
269 wsi->detlat.acc_size = m;
270 wsi->detlat.type = LDLT_WRITE;
271 if (wsi->detlat.earliest_write_req_pre_write)
272 wsi->detlat.latencies[LAT_DUR_PROXY_PROXY_REQ_TO_WRITE] =
273 us - wsi->detlat.earliest_write_req_pre_write;
274 else
275 wsi->detlat.latencies[LAT_DUR_PROXY_PROXY_REQ_TO_WRITE] = 0;
276 wsi->detlat.latencies[LAT_DUR_USERCB] = lws_now_usecs() - us;
277 lws_det_lat_cb(wsi->context, &wsi->detlat);
278
279 }
280 #endif
281
282 return m;
283 }
284
285 int
lws_ssl_capable_read_no_ssl(struct lws * wsi,unsigned char * buf,int len)286 lws_ssl_capable_read_no_ssl(struct lws *wsi, unsigned char *buf, int len)
287 {
288 struct lws_context *context = wsi->context;
289 struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
290 int n = 0;
291
292 lws_stats_bump(pt, LWSSTATS_C_API_READ, 1);
293
294 errno = 0;
295 #if defined(LWS_WITH_UDP)
296 if (lws_wsi_is_udp(wsi)) {
297 wsi->udp->salen = sizeof(wsi->udp->sa);
298 n = recvfrom(wsi->desc.sockfd, (char *)buf, len, 0,
299 &wsi->udp->sa, &wsi->udp->salen);
300 } else
301 #endif
302 n = recv(wsi->desc.sockfd, (char *)buf, len, 0);
303
304 if (n >= 0) {
305
306 if (!n && wsi->unix_skt)
307 return LWS_SSL_CAPABLE_ERROR;
308
309 /*
310 * See https://libwebsockets.org/
311 * pipermail/libwebsockets/2019-March/007857.html
312 */
313 if (!n)
314 return LWS_SSL_CAPABLE_ERROR;
315
316 #if defined(LWS_WITH_SERVER_STATUS)
317 if (wsi->vhost)
318 wsi->vhost->conn_stats.rx += n;
319 #endif
320 lws_stats_bump(pt, LWSSTATS_B_READ, n);
321
322 return n;
323 }
324
325 if (LWS_ERRNO == LWS_EAGAIN ||
326 LWS_ERRNO == LWS_EWOULDBLOCK ||
327 LWS_ERRNO == LWS_EINTR)
328 return LWS_SSL_CAPABLE_MORE_SERVICE;
329
330 lwsl_info("error on reading from skt : %d\n", LWS_ERRNO);
331 return LWS_SSL_CAPABLE_ERROR;
332 }
333
334 int
lws_ssl_capable_write_no_ssl(struct lws * wsi,unsigned char * buf,int len)335 lws_ssl_capable_write_no_ssl(struct lws *wsi, unsigned char *buf, int len)
336 {
337 int n = 0;
338 #if defined(LWS_PLAT_OPTEE)
339 ssize_t send(int sockfd, const void *buf, size_t len, int flags);
340 #endif
341
342 #if defined(LWS_WITH_UDP)
343 if (lws_wsi_is_udp(wsi)) {
344 if (wsi->context->udp_loss_sim_tx_pc) {
345 uint16_t u16;
346 /*
347 * We should randomly drop some of these
348 */
349
350 if (lws_get_random(wsi->context, &u16, 2) == 2 &&
351 ((u16 * 100) / 0xffff) <=
352 wsi->context->udp_loss_sim_tx_pc) {
353 lwsl_warn("%s: dropping udp tx\n", __func__);
354 /* pretend it was sent */
355 n = len;
356 goto post_send;
357 }
358 }
359 if (lws_has_buffered_out(wsi))
360 n = sendto(wsi->desc.sockfd, (const char *)buf,
361 len, 0, &wsi->udp->sa_pending,
362 wsi->udp->salen_pending);
363 else
364 n = sendto(wsi->desc.sockfd, (const char *)buf,
365 len, 0, &wsi->udp->sa, wsi->udp->salen);
366 } else
367 #endif
368 if (wsi->role_ops->file_handle)
369 n = write((int)(long long)wsi->desc.filefd, buf, len);
370 else
371 n = send(wsi->desc.sockfd, (char *)buf, len, MSG_NOSIGNAL);
372 // lwsl_info("%s: sent len %d result %d", __func__, len, n);
373
374 #if defined(LWS_WITH_UDP)
375 post_send:
376 #endif
377 if (n >= 0)
378 return n;
379
380 if (LWS_ERRNO == LWS_EAGAIN ||
381 LWS_ERRNO == LWS_EWOULDBLOCK ||
382 LWS_ERRNO == LWS_EINTR) {
383 if (LWS_ERRNO == LWS_EWOULDBLOCK) {
384 lws_set_blocking_send(wsi);
385 }
386
387 return LWS_SSL_CAPABLE_MORE_SERVICE;
388 }
389
390 lwsl_debug("ERROR writing len %d to skt fd %d err %d / errno %d\n",
391 len, wsi->desc.sockfd, n, LWS_ERRNO);
392
393 return LWS_SSL_CAPABLE_ERROR;
394 }
395
396 int
lws_ssl_pending_no_ssl(struct lws * wsi)397 lws_ssl_pending_no_ssl(struct lws *wsi)
398 {
399 (void)wsi;
400 #if defined(LWS_PLAT_FREERTOS)
401 return 100;
402 #else
403 return 0;
404 #endif
405 }
406