lib/server.c

   1 /*
   2  * libwebsockets - small server side websockets and web server implementation
   3  *
   4  * Copyright (C) 2010-2016 Andy Green <andy@warmcat.com>
   5  *
   6  *  This library is free software; you can redistribute it and/or
   7  *  modify it under the terms of the GNU Lesser General Public
   8  *  License as published by the Free Software Foundation:
   9  *  version 2.1 of the License.
  10  *
  11  *  This library is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  *  Lesser General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU Lesser General Public
  17  *  License along with this library; if not, write to the Free Software
  18  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  19  *  MA  02110-1301  USA
  20  */
  21
  22
  23 #include "private-libwebsockets.h"
  24
  25 #if defined (LWS_WITH_ESP8266)
  26 #undef memcpy
  27 void *memcpy(void *dest, const void *src, size_t n)
  28 {
  29         return ets_memcpy(dest, src, n);
  30 }
  31 #endif
  32
  33 int
  34 lws_context_init_server(struct lws_context_creation_info *info,
  35                         struct lws_vhost *vhost)
  36 {
  37 #if LWS_POSIX
  38         int n, opt = 1, limit = 1;
  39 #endif
  40         lws_sockfd_type sockfd;
  41         struct lws_vhost *vh;
  42         struct lws *wsi;
  43         int m = 0;
  44
  45         (void)opt;
  46         /* set up our external listening socket we serve on */
  47
  48         if (info->port == CONTEXT_PORT_NO_LISTEN || info->port == CONTEXT_PORT_NO_LISTEN_SERVER)
  49                 return 0;
  50
  51         vh = vhost->context->vhost_list;
  52         while (vh) {
  53                 if (vh->listen_port == info->port) {
  54                         if ((!info->iface && !vh->iface) ||
  55                             (info->iface && vh->iface &&
  56                             !strcmp(info->iface, vh->iface))) {
  57                                 vhost->listen_port = info->port;
  58                                 vhost->iface = info->iface;
  59                                 lwsl_notice(" using listen skt from vhost %s\n",
  60                                             vh->name);
  61                                 return 0;
  62                         }
  63                 }
  64                 vh = vh->vhost_next;
  65         }
  66
  67 #if LWS_POSIX
  68 #if defined(__linux__)
  69         limit = vhost->context->count_threads;
  70 #endif
  71
  72         for (m = 0; m < limit; m++) {
  73 #ifdef LWS_USE_UNIX_SOCK
  74         if (LWS_UNIX_SOCK_ENABLED(vhost))
  75                 sockfd = socket(AF_UNIX, SOCK_STREAM, 0);
  76         else
  77 #endif
  78 #ifdef LWS_USE_IPV6
  79         if (LWS_IPV6_ENABLED(vhost))
  80                 sockfd = socket(AF_INET6, SOCK_STREAM, 0);
  81         else
  82 #endif
  83                 sockfd = socket(AF_INET, SOCK_STREAM, 0);
  84
  85         if (sockfd == -1) {
  86 #else
  87 #if defined(LWS_WITH_ESP8266)
  88         sockfd = esp8266_create_tcp_listen_socket(vhost);
  89         if (!lws_sockfd_valid(sockfd)) {
  90 #endif
  91 #endif
  92                 lwsl_err("ERROR opening socket\n");
  93                 return 1;
  94         }
  95 #if LWS_POSIX && !defined(LWS_WITH_ESP32)
  96         /*
  97          * allow us to restart even if old sockets in TIME_WAIT
  98          */
  99         if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR,
 100                        (const void *)&opt, sizeof(opt)) < 0) {
 101                 lwsl_err("reuseaddr failed\n");
 102                 compatible_close(sockfd);
 103                 return 1;
 104         }
 105
 106 #if defined(LWS_USE_IPV6) && defined(IPV6_V6ONLY)
 107         if (LWS_IPV6_ENABLED(vhost)) {
 108                 if (vhost->options & LWS_SERVER_OPTION_IPV6_V6ONLY_MODIFY) {
 109                         int value = (vhost->options & LWS_SERVER_OPTION_IPV6_V6ONLY_VALUE) ? 1 : 0;
 110                         if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_V6ONLY,
 111                                         (const void*)&value, sizeof(value)) < 0) {
 112                                 compatible_close(sockfd);
 113                                 return 1;
 114                         }
 115                 }
 116         }
 117 #endif
 118
 119 #if defined(__linux__) && defined(SO_REUSEPORT) && LWS_MAX_SMP > 1
 120         if (vhost->context->count_threads > 1)
 121                 if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEPORT,
 122                                 (const void *)&opt, sizeof(opt)) < 0) {
 123                         compatible_close(sockfd);
 124                         return 1;
 125                 }
 126 #endif
 127 #endif
 128         lws_plat_set_socket_options(vhost, sockfd);
 129
 130 #if LWS_POSIX
 131         n = lws_socket_bind(vhost, sockfd, info->port, info->iface);
 132         if (n < 0)
 133                 goto bail;
 134         info->port = n;
 135 #endif
 136         vhost->listen_port = info->port;
 137         vhost->iface = info->iface;
 138
 139         wsi = lws_zalloc(sizeof(struct lws));
 140         if (wsi == NULL) {
 141                 lwsl_err("Out of mem\n");
 142                 goto bail;
 143         }
 144         wsi->context = vhost->context;
 145         wsi->desc.sockfd = sockfd;
 146         wsi->mode = LWSCM_SERVER_LISTENER;
 147         wsi->protocol = vhost->protocols;
 148         wsi->tsi = m;
 149         wsi->vhost = vhost;
 150         wsi->listener = 1;
 151
 152 #ifdef LWS_USE_LIBUV
 153         if (LWS_LIBUV_ENABLED(vhost->context))
 154                 lws_uv_initvhost(vhost, wsi);
 155 #endif
 156
 157         if (insert_wsi_socket_into_fds(vhost->context, wsi))
 158                 goto bail;
 159
 160         vhost->context->count_wsi_allocated++;
 161         vhost->lserv_wsi = wsi;
 162
 163 #if LWS_POSIX
 164         n = listen(wsi->desc.sockfd, LWS_SOMAXCONN);
 165         if (n < 0) {
 166                 lwsl_err("listen failed with error %d\n", LWS_ERRNO);
 167                 vhost->lserv_wsi = NULL;
 168                 vhost->context->count_wsi_allocated--;
 169                 remove_wsi_socket_from_fds(wsi);
 170                 goto bail;
 171         }
 172         } /* for each thread able to independently listen */
 173 #else
 174 #if defined(LWS_WITH_ESP8266)
 175         esp8266_tcp_stream_bind(wsi->desc.sockfd, info->port, wsi);
 176 #endif
 177 #endif
 178         if (!lws_check_opt(info->options, LWS_SERVER_OPTION_EXPLICIT_VHOSTS)) {
 179 #ifdef LWS_USE_UNIX_SOCK
 180                 if (LWS_UNIX_SOCK_ENABLED(vhost))
 181                         lwsl_notice(" Listening on \"%s\"\n", info->iface);
 182                 else
 183 #endif
 184                         lwsl_notice(" Listening on port %d\n", info->port);
 185         }
 186
 187         return 0;
 188
 189 bail:
 190         compatible_close(sockfd);
 191
 192         return 1;
 193 }
 194
 195 #if defined(LWS_WITH_ESP8266)
 196 #undef strchr
 197 #define strchr ets_strchr
 198 #endif
 199
 200 struct lws_vhost *
 201 lws_select_vhost(struct lws_context *context, int port, const char *servername)
 202 {
 203         struct lws_vhost *vhost = context->vhost_list;
 204         const char *p;
 205         int n, m, colon;
 206
 207         n = strlen(servername);
 208         colon = n;
 209         p = strchr(servername, ':');
 210         if (p)
 211                 colon = p - servername;
 212
 213         /* Priotity 1: first try exact matches */
 214
 215         while (vhost) {
 216                 if (port == vhost->listen_port &&
 217                     !strncmp(vhost->name, servername, colon)) {
 218                         lwsl_info("SNI: Found: %s\n", servername);
 219                         return vhost;
 220                 }
 221                 vhost = vhost->vhost_next;
 222         }
 223
 224         /*
 225          * Priority 2: if no exact matches, try matching *.vhost-name
 226          * unintentional matches are possible but resolve to x.com for *.x.com
 227          * which is reasonable.  If exact match exists we already chose it and
 228          * never reach here.  SSL will still fail it if the cert doesn't allow
 229          * *.x.com.
 230          */
 231
 232         vhost = context->vhost_list;
 233         while (vhost) {
 234                 m = strlen(vhost->name);
 235                 if (port == vhost->listen_port &&
 236                     m <= (colon - 2) &&
 237                     servername[colon - m - 1] == '.' &&
 238                     !strncmp(vhost->name, servername + colon - m, m)) {
 239                         lwsl_info("SNI: Found %s on wildcard: %s\n",
 240                                     servername, vhost->name);
 241                         return vhost;
 242                 }
 243                 vhost = vhost->vhost_next;
 244         }
 245
 246         /* Priority 3: match the first vhost on our port */
 247
 248         vhost = context->vhost_list;
 249         while (vhost) {
 250                 if (port == vhost->listen_port) {
 251                         lwsl_info("vhost match to %s based on port %d\n",
 252                                         vhost->name, port);
 253                         return vhost;
 254                 }
 255                 vhost = vhost->vhost_next;
 256         }
 257
 258         /* no match */
 259
 260         return NULL;
 261 }
 262
 263 LWS_VISIBLE LWS_EXTERN const char *
 264 lws_get_mimetype(const char *file, const struct lws_http_mount *m)
 265 {
 266         int n = strlen(file);
 267         const struct lws_protocol_vhost_options *pvo = NULL;
 268
 269         if (m)
 270                 pvo = m->extra_mimetypes;
 271
 272         if (n < 5)
 273                 return NULL;
 274
 275         if (!strcmp(&file[n - 4], ".ico"))
 276                 return "image/x-icon";
 277
 278         if (!strcmp(&file[n - 4], ".gif"))
 279                 return "image/gif";
 280
 281         if (!strcmp(&file[n - 3], ".js"))
 282                 return "text/javascript";
 283
 284         if (!strcmp(&file[n - 4], ".png"))
 285                 return "image/png";
 286
 287         if (!strcmp(&file[n - 4], ".jpg"))
 288                 return "image/jpeg";
 289
 290         if (!strcmp(&file[n - 3], ".gz"))
 291                 return "application/gzip";
 292
 293         if (!strcmp(&file[n - 4], ".JPG"))
 294                 return "image/jpeg";
 295
 296         if (!strcmp(&file[n - 5], ".html"))
 297                 return "text/html";
 298
 299         if (!strcmp(&file[n - 4], ".css"))
 300                 return "text/css";
 301
 302         if (!strcmp(&file[n - 4], ".txt"))
 303                 return "text/plain";
 304
 305         if (!strcmp(&file[n - 4], ".svg"))
 306                 return "image/svg+xml";
 307
 308         if (!strcmp(&file[n - 4], ".ttf"))
 309                 return "application/x-font-ttf";
 310
 311         if (!strcmp(&file[n - 5], ".woff"))
 312                 return "application/font-woff";
 313
 314         if (!strcmp(&file[n - 4], ".xml"))
 315                 return "application/xml";
 316
 317         while (pvo) {
 318                 if (pvo->name[0] == '*') /* ie, match anything */
 319                         return pvo->value;
 320
 321                 if (!strcmp(&file[n - strlen(pvo->name)], pvo->name))
 322                         return pvo->value;
 323
 324                 pvo = pvo->next;
 325         }
 326
 327         return NULL;
 328 }
 329 static lws_fop_flags_t
 330 lws_vfs_prepare_flags(struct lws *wsi)
 331 {
 332         lws_fop_flags_t f = 0;
 333
 334         if (!lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_ACCEPT_ENCODING))
 335                 return f;
 336
 337         if (strstr(lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP_ACCEPT_ENCODING),
 338                    "gzip")) {
 339                 lwsl_info("client indicates GZIP is acceptable\n");
 340                 f |= LWS_FOP_FLAG_COMPR_ACCEPTABLE_GZIP;
 341         }
 342
 343         return f;
 344 }
 345
 346 static int
 347 lws_http_serve(struct lws *wsi, char *uri, const char *origin,
 348                const struct lws_http_mount *m)
 349 {
 350         const struct lws_protocol_vhost_options *pvo = m->interpret;
 351         struct lws_process_html_args args;
 352         const char *mimetype;
 353 #if !defined(_WIN32_WCE) && !defined(LWS_WITH_ESP8266)
 354         const struct lws_plat_file_ops *fops;
 355         const char *vpath;
 356         lws_fop_flags_t fflags = LWS_O_RDONLY;
 357         struct stat st;
 358         int spin = 0;
 359 #endif
 360         char path[256], sym[512];
 361         unsigned char *p = (unsigned char *)sym + 32 + LWS_PRE, *start = p;
 362         unsigned char *end = p + sizeof(sym) - 32 - LWS_PRE;
 363 #if !defined(WIN32) && LWS_POSIX && !defined(LWS_WITH_ESP32)
 364         size_t len;
 365 #endif
 366         int n;
 367
 368         lws_snprintf(path, sizeof(path) - 1, "%s/%s", origin, uri);
 369
 370 #if !defined(_WIN32_WCE) && !defined(LWS_WITH_ESP8266)
 371
 372         fflags |= lws_vfs_prepare_flags(wsi);
 373
 374         do {
 375                 spin++;
 376                 fops = lws_vfs_select_fops(wsi->context->fops, path, &vpath);
 377
 378                 if (wsi->u.http.fop_fd)
 379                         lws_vfs_file_close(&wsi->u.http.fop_fd);
 380
 381                 wsi->u.http.fop_fd = fops->LWS_FOP_OPEN(wsi->context->fops,
 382                                                         path, vpath, &fflags);
 383                 if (!wsi->u.http.fop_fd) {
 384                         lwsl_err("Unable to open '%s'\n", path);
 385
 386                         return -1;
 387                 }
 388
 389                 /* if it can't be statted, don't try */
 390                 if (fflags & LWS_FOP_FLAG_VIRTUAL)
 391                         break;
 392 #if defined(LWS_WITH_ESP32)
 393                 break;
 394 #endif
 395 #if !defined(WIN32)
 396                 if (fstat(wsi->u.http.fop_fd->fd, &st)) {
 397                         lwsl_info("unable to stat %s\n", path);
 398                         goto bail;
 399                 }
 400 #else
 401                 if (stat(path, &st)) {
 402                         lwsl_info("unable to stat %s\n", path);
 403                         goto bail;
 404                 }
 405 #endif
 406
 407                 wsi->u.http.fop_fd->mod_time = (uint32_t)st.st_mtime;
 408                 fflags |= LWS_FOP_FLAG_MOD_TIME_VALID;
 409
 410                 lwsl_debug(" %s mode %d\n", path, S_IFMT & st.st_mode);
 411 #if !defined(WIN32) && LWS_POSIX && !defined(LWS_WITH_ESP32)
 412                 if ((S_IFMT & st.st_mode) == S_IFLNK) {
 413                         len = readlink(path, sym, sizeof(sym) - 1);
 414                         if (len) {
 415                                 lwsl_err("Failed to read link %s\n", path);
 416                                 goto bail;
 417                         }
 418                         sym[len] = '\0';
 419                         lwsl_debug("symlink %s -> %s\n", path, sym);
 420                         lws_snprintf(path, sizeof(path) - 1, "%s", sym);
 421                 }
 422 #endif
 423                 if ((S_IFMT & st.st_mode) == S_IFDIR) {
 424                         lwsl_debug("default filename append to dir\n");
 425                         lws_snprintf(path, sizeof(path) - 1, "%s/%s/index.html",
 426                                  origin, uri);
 427                 }
 428
 429         } while ((S_IFMT & st.st_mode) != S_IFREG && spin < 5);
 430
 431         if (spin == 5)
 432                 lwsl_err("symlink loop %s \n", path);
 433
 434         n = sprintf(sym, "%08lX%08lX",
 435                     (unsigned long)lws_vfs_get_length(wsi->u.http.fop_fd),
 436                     (unsigned long)lws_vfs_get_mod_time(wsi->u.http.fop_fd));
 437
 438         /* disable ranges if IF_RANGE token invalid */
 439
 440         if (lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_IF_RANGE))
 441                 if (strcmp(sym, lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP_IF_RANGE)))
 442                         /* differs - defeat Range: */
 443                         wsi->u.http.ah->frag_index[WSI_TOKEN_HTTP_RANGE] = 0;
 444
 445         if (lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_IF_NONE_MATCH)) {
 446                 /*
 447                  * he thinks he has some version of it already,
 448                  * check if the tag matches
 449                  */
 450                 if (!strcmp(sym, lws_hdr_simple_ptr(wsi,
 451                                         WSI_TOKEN_HTTP_IF_NONE_MATCH))) {
 452
 453                         lwsl_debug("%s: ETAG match %s %s\n", __func__,
 454                                    uri, origin);
 455
 456                         /* we don't need to send the payload */
 457                         if (lws_add_http_header_status(wsi,
 458                                         HTTP_STATUS_NOT_MODIFIED, &p, end))
 459                                 return -1;
 460
 461                         if (lws_add_http_header_by_token(wsi,
 462                                         WSI_TOKEN_HTTP_ETAG,
 463                                         (unsigned char *)sym, n, &p, end))
 464                                 return -1;
 465
 466                         if (lws_finalize_http_header(wsi, &p, end))
 467                                 return -1;
 468
 469                         n = lws_write(wsi, start, p - start,
 470                                       LWS_WRITE_HTTP_HEADERS);
 471                         if (n != (p - start)) {
 472                                 lwsl_err("_write returned %d from %ld\n", n,
 473                                          (long)(p - start));
 474                                 return -1;
 475                         }
 476
 477                         lws_vfs_file_close(&wsi->u.http.fop_fd);
 478
 479                         return lws_http_transaction_completed(wsi);
 480                 }
 481         }
 482
 483         if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_ETAG,
 484                         (unsigned char *)sym, n, &p, end))
 485                 return -1;
 486 #endif
 487
 488         mimetype = lws_get_mimetype(path, m);
 489         if (!mimetype) {
 490                 lwsl_err("unknown mimetype for %s\n", path);
 491                goto bail;
 492         }
 493         if (!mimetype[0])
 494                 lwsl_debug("sending no mimetype for %s\n", path);
 495
 496         wsi->sending_chunked = 0;
 497
 498         /*
 499          * check if this is in the list of file suffixes to be interpreted by
 500          * a protocol
 501          */
 502         while (pvo) {
 503                 n = strlen(path);
 504                 if (n > (int)strlen(pvo->name) &&
 505                     !strcmp(&path[n - strlen(pvo->name)], pvo->name)) {
 506                         wsi->sending_chunked = 1;
 507                         wsi->protocol_interpret_idx = (char)(long)pvo->value;
 508                         lwsl_info("want %s interpreted by %s\n", path,
 509                                     wsi->vhost->protocols[(int)(long)(pvo->value)].name);
 510                         wsi->protocol = &wsi->vhost->protocols[(int)(long)(pvo->value)];
 511                         if (lws_ensure_user_space(wsi))
 512                                 return -1;
 513                         break;
 514                 }
 515                 pvo = pvo->next;
 516         }
 517
 518         if (m->protocol) {
 519                 const struct lws_protocols *pp = lws_vhost_name_to_protocol(
 520                                                         wsi->vhost, m->protocol);
 521
 522                 if (lws_bind_protocol(wsi, pp))
 523                         return 1;
 524                 args.p = (char *)p;
 525                 args.max_len = end - p;
 526                 if (pp->callback(wsi, LWS_CALLBACK_ADD_HEADERS,
 527                                           wsi->user_space, &args, 0))
 528                         return -1;
 529                 p = (unsigned char *)args.p;
 530         }
 531
 532         n = lws_serve_http_file(wsi, path, mimetype, (char *)start, p - start);
 533
 534         if (n < 0 || ((n > 0) && lws_http_transaction_completed(wsi)))
 535                 return -1; /* error or can't reuse connection: close the socket */
 536
 537         return 0;
 538 bail:
 539
 540         return -1;
 541 }
 542
 543 const struct lws_http_mount *
 544 lws_find_mount(struct lws *wsi, const char *uri_ptr, int uri_len)
 545 {
 546         const struct lws_http_mount *hm, *hit = NULL;
 547         int best = 0;
 548
 549         hm = wsi->vhost->mount_list;
 550         while (hm) {
 551                 if (uri_len >= hm->mountpoint_len &&
 552                     !strncmp(uri_ptr, hm->mountpoint, hm->mountpoint_len) &&
 553                     (uri_ptr[hm->mountpoint_len] == '\0' ||
 554                      uri_ptr[hm->mountpoint_len] == '/' ||
 555                      hm->mountpoint_len == 1)
 556                     ) {
 557                         if (hm->origin_protocol == LWSMPRO_CALLBACK ||
 558                             ((hm->origin_protocol == LWSMPRO_CGI ||
 559                              lws_hdr_total_length(wsi, WSI_TOKEN_GET_URI) ||
 560                              hm->protocol) &&
 561                             hm->mountpoint_len > best)) {
 562                                 best = hm->mountpoint_len;
 563                                 hit = hm;
 564                         }
 565                 }
 566                 hm = hm->mount_next;
 567         }
 568
 569         return hit;
 570 }
 571
 572 #if LWS_POSIX
 573
 574 static int
 575 lws_find_string_in_file(const char *filename, const char *string, int stringlen)
 576 {
 577         char buf[128];
 578         int fd, match = 0, pos = 0, n = 0, hit = 0;
 579
 580         fd = open(filename, O_RDONLY);
 581         if (fd < 0) {
 582                 lwsl_err("can't open auth file: %s\n", filename);
 583                 return 1;
 584         }
 585
 586         while (1) {
 587                 if (pos == n) {
 588                         n = read(fd, buf, sizeof(buf));
 589                         if (n <= 0) {
 590                                 if (match == stringlen)
 591                                         hit = 1;
 592                                 break;
 593                         }
 594                         pos = 0;
 595                 }
 596
 597                 if (match == stringlen) {
 598                         if (buf[pos] == '\r' || buf[pos] == '\n') {
 599                                 hit = 1;
 600                                 break;
 601                         }
 602                         match = 0;
 603                 }
 604
 605                 if (buf[pos] == string[match])
 606                         match++;
 607                 else
 608                         match = 0;
 609
 610                 pos++;
 611         }
 612
 613         close(fd);
 614
 615         return hit;
 616 }
 617
 618 static int
 619 lws_unauthorised_basic_auth(struct lws *wsi)
 620 {
 621         struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
 622         unsigned char *start = pt->serv_buf + LWS_PRE,
 623                       *p = start, *end = p + 512;
 624         char buf[64];
 625         int n;
 626
 627         /* no auth... tell him it is required */
 628
 629         if (lws_add_http_header_status(wsi, HTTP_STATUS_UNAUTHORIZED, &p, end))
 630                 return -1;
 631
 632         n = lws_snprintf(buf, sizeof(buf), "Basic realm=\"lwsws\"");
 633         if (lws_add_http_header_by_token(wsi,
 634                         WSI_TOKEN_HTTP_WWW_AUTHENTICATE,
 635                         (unsigned char *)buf, n, &p, end))
 636                 return -1;
 637
 638         if (lws_finalize_http_header(wsi, &p, end))
 639                 return -1;
 640
 641         n = lws_write(wsi, start, p - start, LWS_WRITE_HTTP_HEADERS);
 642         if (n < 0)
 643                 return -1;
 644
 645         return lws_http_transaction_completed(wsi);
 646
 647 }
 648
 649 #endif
 650
 651 int
 652 lws_http_action(struct lws *wsi)
 653 {
 654         struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
 655         enum http_connection_type connection_type;
 656         enum http_version request_version;
 657         char content_length_str[32];
 658         struct lws_process_html_args args;
 659         const struct lws_http_mount *hit = NULL;
 660         unsigned int n, count = 0;
 661         char http_version_str[10];
 662         char http_conn_str[20];
 663         int http_version_len;
 664         char *uri_ptr = NULL, *s;
 665         int uri_len = 0;
 666         int meth = -1;
 667
 668         static const unsigned char methods[] = {
 669                 WSI_TOKEN_GET_URI,
 670                 WSI_TOKEN_POST_URI,
 671                 WSI_TOKEN_OPTIONS_URI,
 672                 WSI_TOKEN_PUT_URI,
 673                 WSI_TOKEN_PATCH_URI,
 674                 WSI_TOKEN_DELETE_URI,
 675                 WSI_TOKEN_CONNECT,
 676 #ifdef LWS_USE_HTTP2
 677                 WSI_TOKEN_HTTP_COLON_PATH,
 678 #endif
 679         };
 680 #if defined(_DEBUG) || defined(LWS_WITH_ACCESS_LOG)
 681         static const char * const method_names[] = {
 682                 "GET", "POST", "OPTIONS", "PUT", "PATCH", "DELETE", "CONNECT",
 683 #ifdef LWS_USE_HTTP2
 684                 ":path",
 685 #endif
 686         };
 687 #endif
 688         static const char * const oprot[] = {
 689                 "http://", "https://"
 690         };
 691
 692         /* it's not websocket.... shall we accept it as http? */
 693
 694         for (n = 0; n < ARRAY_SIZE(methods); n++)
 695                 if (lws_hdr_total_length(wsi, methods[n]))
 696                         count++;
 697         if (!count) {
 698                 lwsl_warn("Missing URI in HTTP request\n");
 699                 goto bail_nuke_ah;
 700         }
 701
 702         if (count != 1) {
 703                 lwsl_warn("multiple methods?\n");
 704                 goto bail_nuke_ah;
 705         }
 706
 707         if (lws_ensure_user_space(wsi))
 708                 goto bail_nuke_ah;
 709
 710         for (n = 0; n < ARRAY_SIZE(methods); n++)
 711                 if (lws_hdr_total_length(wsi, methods[n])) {
 712                         uri_ptr = lws_hdr_simple_ptr(wsi, methods[n]);
 713                         uri_len = lws_hdr_total_length(wsi, methods[n]);
 714                         lwsl_info("Method: %s request for '%s'\n",
 715                                         method_names[n], uri_ptr);
 716                         meth = n;
 717                         break;
 718                 }
 719
 720         (void)meth;
 721
 722         /* we insist on absolute paths */
 723
 724         if (uri_ptr[0] != '/') {
 725                 lws_return_http_status(wsi, HTTP_STATUS_FORBIDDEN, NULL);
 726
 727                 goto bail_nuke_ah;
 728         }
 729
 730         /* HTTP header had a content length? */
 731
 732         wsi->u.http.content_length = 0;
 733         if (lws_hdr_total_length(wsi, WSI_TOKEN_POST_URI) ||
 734                 lws_hdr_total_length(wsi, WSI_TOKEN_PATCH_URI) ||
 735                 lws_hdr_total_length(wsi, WSI_TOKEN_PUT_URI))
 736                 wsi->u.http.content_length = 100 * 1024 * 1024;
 737
 738         if (lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_CONTENT_LENGTH)) {
 739                 lws_hdr_copy(wsi, content_length_str,
 740                              sizeof(content_length_str) - 1,
 741                              WSI_TOKEN_HTTP_CONTENT_LENGTH);
 742                 wsi->u.http.content_length = atoi(content_length_str);
 743         }
 744
 745         if (wsi->http2_substream) {
 746                 wsi->u.http.request_version = HTTP_VERSION_2;
 747         } else {
 748                 /* http_version? Default to 1.0, override with token: */
 749                 request_version = HTTP_VERSION_1_0;
 750
 751                 /* Works for single digit HTTP versions. : */
 752                 http_version_len = lws_hdr_total_length(wsi, WSI_TOKEN_HTTP);
 753                 if (http_version_len > 7) {
 754                         lws_hdr_copy(wsi, http_version_str,
 755                                         sizeof(http_version_str) - 1, WSI_TOKEN_HTTP);
 756                         if (http_version_str[5] == '1' && http_version_str[7] == '1')
 757                                 request_version = HTTP_VERSION_1_1;
 758                 }
 759                 wsi->u.http.request_version = request_version;
 760
 761                 /* HTTP/1.1 defaults to "keep-alive", 1.0 to "close" */
 762                 if (request_version == HTTP_VERSION_1_1)
 763                         connection_type = HTTP_CONNECTION_KEEP_ALIVE;
 764                 else
 765                         connection_type = HTTP_CONNECTION_CLOSE;
 766
 767                 /* Override default if http "Connection:" header: */
 768                 if (lws_hdr_total_length(wsi, WSI_TOKEN_CONNECTION)) {
 769                         lws_hdr_copy(wsi, http_conn_str, sizeof(http_conn_str) - 1,
 770                                      WSI_TOKEN_CONNECTION);
 771                         http_conn_str[sizeof(http_conn_str) - 1] = '\0';
 772                         if (!strcasecmp(http_conn_str, "keep-alive"))
 773                                 connection_type = HTTP_CONNECTION_KEEP_ALIVE;
 774                         else
 775                                 if (!strcasecmp(http_conn_str, "close"))
 776                                         connection_type = HTTP_CONNECTION_CLOSE;
 777                 }
 778                 wsi->u.http.connection_type = connection_type;
 779         }
 780
 781         n = wsi->protocol->callback(wsi, LWS_CALLBACK_FILTER_HTTP_CONNECTION,
 782                                     wsi->user_space, uri_ptr, uri_len);
 783         if (n) {
 784                 lwsl_info("LWS_CALLBACK_HTTP closing\n");
 785
 786                 return 1;
 787         }
 788         /*
 789          * if there is content supposed to be coming,
 790          * put a timeout on it having arrived
 791          */
 792         lws_set_timeout(wsi, PENDING_TIMEOUT_HTTP_CONTENT,
 793                         wsi->context->timeout_secs);
 794 #ifdef LWS_OPENSSL_SUPPORT
 795         if (wsi->redirect_to_https) {
 796                 /*
 797                  * we accepted http:// only so we could redirect to
 798                  * https://, so issue the redirect.  Create the redirection
 799                  * URI from the host: header and ignore the path part
 800                  */
 801                 unsigned char *start = pt->serv_buf + LWS_PRE, *p = start,
 802                               *end = p + 512;
 803
 804                 if (!lws_hdr_total_length(wsi, WSI_TOKEN_HOST))
 805                         goto bail_nuke_ah;
 806
 807                 n = sprintf((char *)end, "https://%s/",
 808                             lws_hdr_simple_ptr(wsi, WSI_TOKEN_HOST));
 809
 810                 n = lws_http_redirect(wsi, HTTP_STATUS_MOVED_PERMANENTLY,
 811                                       end, n, &p, end);
 812                 if ((int)n < 0)
 813                         goto bail_nuke_ah;
 814
 815                 return lws_http_transaction_completed(wsi);
 816         }
 817 #endif
 818
 819 #ifdef LWS_WITH_ACCESS_LOG
 820         /*
 821          * Produce Apache-compatible log string for wsi, like this:
 822          *
 823          * 2.31.234.19 - - [27/Mar/2016:03:22:44 +0800]
 824          * "GET /aep-screen.png HTTP/1.1"
 825          * 200 152987 "https://libwebsockets.org/index.html"
 826          * "Mozilla/5.0 (Macint... Chrome/49.0.2623.87 Safari/537.36"
 827          *
 828          */
 829         {
 830                 static const char * const hver[] = {
 831                         "http/1.0", "http/1.1", "http/2"
 832                 };
 833 #ifdef LWS_USE_IPV6
 834                 char ads[INET6_ADDRSTRLEN];
 835 #else
 836                 char ads[INET_ADDRSTRLEN];
 837 #endif
 838                 char da[64];
 839                 const char *pa, *me;
 840                 struct tm *tmp;
 841                 time_t t = time(NULL);
 842                 int l = 256;
 843
 844                 if (wsi->access_log_pending)
 845                         lws_access_log(wsi);
 846
 847                 wsi->access_log.header_log = lws_malloc(l);
 848                 if (wsi->access_log.header_log) {
 849
 850                         tmp = localtime(&t);
 851                         if (tmp)
 852                                 strftime(da, sizeof(da), "%d/%b/%Y:%H:%M:%S %z", tmp);
 853                         else
 854                                 strcpy(da, "01/Jan/1970:00:00:00 +0000");
 855
 856                         pa = lws_get_peer_simple(wsi, ads, sizeof(ads));
 857                         if (!pa)
 858                                 pa = "(unknown)";
 859
 860                         if (meth >= 0)
 861                                 me = method_names[meth];
 862                         else
 863                                 me = "unknown";
 864
 865                         lws_snprintf(wsi->access_log.header_log, l,
 866                                  "%s - - [%s] \"%s %s %s\"",
 867                                  pa, da, me, uri_ptr,
 868                                  hver[wsi->u.http.request_version]);
 869
 870                         l = lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_USER_AGENT);
 871                         if (l) {
 872                                 wsi->access_log.user_agent = lws_malloc(l + 2);
 873                                 if (wsi->access_log.user_agent)
 874                                         lws_hdr_copy(wsi, wsi->access_log.user_agent,
 875                                                         l + 1, WSI_TOKEN_HTTP_USER_AGENT);
 876                                 else
 877                                         lwsl_err("OOM getting user agent\n");
 878                         }
 879                         wsi->access_log_pending = 1;
 880                 }
 881         }
 882 #endif
 883
 884         /* can we serve it from the mount list? */
 885
 886         hit = lws_find_mount(wsi, uri_ptr, uri_len);
 887         if (!hit) {
 888                 /* deferred cleanup and reset to protocols[0] */
 889
 890                 lwsl_info("no hit\n");
 891
 892                 if (lws_bind_protocol(wsi, &wsi->vhost->protocols[0]))
 893                         return 1;
 894
 895                 n = wsi->protocol->callback(wsi, LWS_CALLBACK_HTTP,
 896                                     wsi->user_space, uri_ptr, uri_len);
 897
 898                 goto after;
 899         }
 900
 901         s = uri_ptr + hit->mountpoint_len;
 902
 903         /*
 904          * if we have a mountpoint like https://xxx.com/yyy
 905          * there is an implied / at the end for our purposes since
 906          * we can only mount on a "directory".
 907          *
 908          * But if we just go with that, the browser cannot understand
 909          * that he is actually looking down one "directory level", so
 910          * even though we give him /yyy/abc.html he acts like the
 911          * current directory level is /.  So relative urls like "x.png"
 912          * wrongly look outside the mountpoint.
 913          *
 914          * Therefore if we didn't come in on a url with an explicit
 915          * / at the end, we must redirect to add it so the browser
 916          * understands he is one "directory level" down.
 917          */
 918         if ((hit->mountpoint_len > 1 ||
 919              (hit->origin_protocol == LWSMPRO_REDIR_HTTP ||
 920               hit->origin_protocol == LWSMPRO_REDIR_HTTPS)) &&
 921             (*s != '/' ||
 922              (hit->origin_protocol == LWSMPRO_REDIR_HTTP ||
 923               hit->origin_protocol == LWSMPRO_REDIR_HTTPS)) &&
 924             (hit->origin_protocol != LWSMPRO_CGI &&
 925              hit->origin_protocol != LWSMPRO_CALLBACK //&&
 926              //hit->protocol == NULL
 927              )) {
 928                 unsigned char *start = pt->serv_buf + LWS_PRE,
 929                               *p = start, *end = p + 512;
 930
 931                 lwsl_debug("Doing 301 '%s' org %s\n", s, hit->origin);
 932
 933                 if (!lws_hdr_total_length(wsi, WSI_TOKEN_HOST))
 934                         goto bail_nuke_ah;
 935
 936                 /* > at start indicates deal with by redirect */
 937                 if (hit->origin_protocol == LWSMPRO_REDIR_HTTP ||
 938                     hit->origin_protocol == LWSMPRO_REDIR_HTTPS)
 939                         n = lws_snprintf((char *)end, 256, "%s%s",
 940                                     oprot[hit->origin_protocol & 1],
 941                                     hit->origin);
 942                 else
 943                         n = lws_snprintf((char *)end, 256,
 944                             "%s%s%s/", oprot[lws_is_ssl(wsi)],
 945                             lws_hdr_simple_ptr(wsi, WSI_TOKEN_HOST),
 946                             uri_ptr);
 947
 948                 n = lws_http_redirect(wsi, HTTP_STATUS_MOVED_PERMANENTLY,
 949                                       end, n, &p, end);
 950                 if ((int)n < 0)
 951                         goto bail_nuke_ah;
 952
 953                 return lws_http_transaction_completed(wsi);
 954         }
 955
 956 #if LWS_POSIX
 957         /* basic auth? */
 958
 959         if (hit->basic_auth_login_file) {
 960                 char b64[160], plain[(sizeof(b64) * 3) / 4];
 961                 int m;
 962
 963                 /* Did he send auth? */
 964                 if (!lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_AUTHORIZATION))
 965                         return lws_unauthorised_basic_auth(wsi);
 966
 967                 n = HTTP_STATUS_FORBIDDEN;
 968
 969                 m = lws_hdr_copy(wsi, b64, sizeof(b64), WSI_TOKEN_HTTP_AUTHORIZATION);
 970                 if (m < 7) {
 971                         lwsl_err("b64 auth too long\n");
 972                         goto transaction_result_n;
 973                 }
 974
 975                 b64[5] = '\0';
 976                 if (strcasecmp(b64, "Basic")) {
 977                         lwsl_err("auth missing basic: %s\n", b64);
 978                         goto transaction_result_n;
 979                 }
 980
 981                 /* It'll be like Authorization: Basic QWxhZGRpbjpPcGVuU2VzYW1l */
 982
 983                 m = lws_b64_decode_string(b64 + 6, plain, sizeof(plain));
 984                 if (m < 0) {
 985                         lwsl_err("plain auth too long\n");
 986                         goto transaction_result_n;
 987                 }
 988
 989 //              lwsl_notice(plain);
 990
 991                 if (!lws_find_string_in_file(hit->basic_auth_login_file, plain, m)) {
 992                         lwsl_err("basic auth lookup failed\n");
 993                         return lws_unauthorised_basic_auth(wsi);
 994                 }
 995
 996                 lwsl_notice("basic auth accepted\n");
 997
 998                 /* accept the auth */
 999         }
1000 #endif
1001
1002         /*
1003          * A particular protocol callback is mounted here?
1004          *
1005          * For the duration of this http transaction, bind us to the
1006          * associated protocol
1007          */
1008         if (hit->origin_protocol == LWSMPRO_CALLBACK || hit->protocol) {
1009                 const struct lws_protocols *pp;
1010                 const char *name = hit->origin;
1011                 if (hit->protocol)
1012                         name = hit->protocol;
1013
1014                 pp = lws_vhost_name_to_protocol(wsi->vhost, name);
1015                 if (!pp) {
1016                         n = -1;
1017                         lwsl_err("Unable to find plugin '%s'\n",
1018                                  hit->origin);
1019                         return 1;
1020                 }
1021
1022                 if (lws_bind_protocol(wsi, pp))
1023                         return 1;
1024
1025                 args.p = uri_ptr;
1026                 args.len = uri_len;
1027                 args.max_len = hit->auth_mask;
1028                 args.final = 0; /* used to signal callback dealt with it */
1029
1030                 n = wsi->protocol->callback(wsi, LWS_CALLBACK_CHECK_ACCESS_RIGHTS,
1031                                             wsi->user_space, &args, 0);
1032                 if (n) {
1033                         lws_return_http_status(wsi, HTTP_STATUS_UNAUTHORIZED,
1034                                                NULL);
1035                         goto bail_nuke_ah;
1036                 }
1037                 if (args.final) /* callback completely handled it well */
1038                         return 0;
1039
1040                 if (hit->cgienv && wsi->protocol->callback(wsi,
1041                                 LWS_CALLBACK_HTTP_PMO,
1042                                 wsi->user_space, (void *)hit->cgienv, 0))
1043                         return 1;
1044
1045                 if (lws_hdr_total_length(wsi, WSI_TOKEN_POST_URI)) {
1046                         n = wsi->protocol->callback(wsi, LWS_CALLBACK_HTTP,
1047                                             wsi->user_space,
1048                                             uri_ptr + hit->mountpoint_len,
1049                                             uri_len - hit->mountpoint_len);
1050                         goto after;
1051                 }
1052         }
1053
1054 #ifdef LWS_WITH_CGI
1055         /* did we hit something with a cgi:// origin? */
1056         if (hit->origin_protocol == LWSMPRO_CGI) {
1057                 const char *cmd[] = {
1058                         NULL, /* replace with cgi path */
1059                         NULL
1060                 };
1061                 unsigned char *p, *end, buffer[1024];
1062
1063                 lwsl_debug("%s: cgi\n", __func__);
1064                 cmd[0] = hit->origin;
1065
1066                 n = 5;
1067                 if (hit->cgi_timeout)
1068                         n = hit->cgi_timeout;
1069
1070                 n = lws_cgi(wsi, cmd, hit->mountpoint_len, n,
1071                             hit->cgienv);
1072                 if (n) {
1073                         lwsl_err("%s: cgi failed\n", __func__);
1074                         return -1;
1075                 }
1076                 p = buffer + LWS_PRE;
1077                 end = p + sizeof(buffer) - LWS_PRE;
1078
1079                 if (lws_add_http_header_status(wsi, HTTP_STATUS_OK, &p, end))
1080                         return 1;
1081                 if (lws_add_http_header_by_token(wsi, WSI_TOKEN_CONNECTION,
1082                                 (unsigned char *)"close", 5, &p, end))
1083                         return 1;
1084                 n = lws_write(wsi, buffer + LWS_PRE,
1085                               p - (buffer + LWS_PRE),
1086                               LWS_WRITE_HTTP_HEADERS);
1087
1088                 goto deal_body;
1089         }
1090 #endif
1091
1092         n = strlen(s);
1093         if (s[0] == '\0' || (n == 1 && s[n - 1] == '/'))
1094                 s = (char *)hit->def;
1095         if (!s)
1096                 s = "index.html";
1097
1098         wsi->cache_secs = hit->cache_max_age;
1099         wsi->cache_reuse = hit->cache_reusable;
1100         wsi->cache_revalidate = hit->cache_revalidate;
1101         wsi->cache_intermediaries = hit->cache_intermediaries;
1102
1103         n = lws_http_serve(wsi, s, hit->origin, hit);
1104         if (n) {
1105                 /*
1106                  *      lws_return_http_status(wsi, HTTP_STATUS_NOT_FOUND, NULL);
1107                  */
1108                 if (hit->protocol) {
1109                         const struct lws_protocols *pp = lws_vhost_name_to_protocol(
1110                                         wsi->vhost, hit->protocol);
1111
1112                         if (lws_bind_protocol(wsi, pp))
1113                                 return 1;
1114
1115                         n = pp->callback(wsi, LWS_CALLBACK_HTTP,
1116                                          wsi->user_space,
1117                                          uri_ptr + hit->mountpoint_len,
1118                                          uri_len - hit->mountpoint_len);
1119                 } else
1120                         n = wsi->protocol->callback(wsi, LWS_CALLBACK_HTTP,
1121                                     wsi->user_space, uri_ptr, uri_len);
1122         }
1123
1124 after:
1125         if (n) {
1126                 lwsl_info("LWS_CALLBACK_HTTP closing\n");
1127
1128                 return 1;
1129         }
1130
1131 #ifdef LWS_WITH_CGI
1132 deal_body:
1133 #endif
1134         /*
1135          * If we're not issuing a file, check for content_length or
1136          * HTTP keep-alive. No keep-alive header allocation for
1137          * ISSUING_FILE, as this uses HTTP/1.0.
1138          *
1139          * In any case, return 0 and let lws_read decide how to
1140          * proceed based on state
1141          */
1142         if (wsi->state != LWSS_HTTP_ISSUING_FILE)
1143                 /* Prepare to read body if we have a content length: */
1144                 if (wsi->u.http.content_length > 0)
1145                         wsi->state = LWSS_HTTP_BODY;
1146
1147         return 0;
1148
1149 bail_nuke_ah:
1150         /* we're closing, losing some rx is OK */
1151         wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
1152         // lwsl_notice("%s: drop1\n", __func__);
1153         lws_header_table_detach(wsi, 1);
1154
1155         return 1;
1156 #if LWS_POSIX
1157 transaction_result_n:
1158         lws_return_http_status(wsi, n, NULL);
1159
1160         return lws_http_transaction_completed(wsi);
1161 #endif
1162 }
1163
1164 int
1165 lws_handshake_server(struct lws *wsi, unsigned char **buf, size_t len)
1166 {
1167         int protocol_len, n = 0, hit, non_space_char_found = 0, m;
1168         struct lws_context *context = lws_get_context(wsi);
1169         struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
1170         struct _lws_header_related hdr;
1171         struct allocated_headers *ah;
1172         unsigned char *obuf = *buf;
1173         char protocol_list[128];
1174         char protocol_name[64];
1175         size_t olen = len;
1176         char *p;
1177
1178         if (len >= 10000000) {
1179                 lwsl_err("%s: assert: len %ld\n", __func__, (long)len);
1180                 assert(0);
1181         }
1182
1183         if (!wsi->u.hdr.ah) {
1184                 lwsl_err("%s: assert: NULL ah\n", __func__);
1185                 assert(0);
1186         }
1187
1188         while (len--) {
1189                 wsi->more_rx_waiting = !!len;
1190
1191                 if (wsi->mode != LWSCM_HTTP_SERVING &&
1192                     wsi->mode != LWSCM_HTTP_SERVING_ACCEPTED) {
1193                         lwsl_err("%s: bad wsi mode %d\n", __func__, wsi->mode);
1194                         goto bail_nuke_ah;
1195                 }
1196
1197                 m = lws_parse(wsi, *(*buf)++);
1198                 if (m) {
1199                         if (m == 2) {
1200                                 /*
1201                                  * we are transitioning from http with
1202                                  * an AH, to raw.  Drop the ah and set
1203                                  * the mode.
1204                                  */
1205 raw_transition:
1206                                 lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
1207                                 lws_bind_protocol(wsi, &wsi->vhost->protocols[
1208                                                         wsi->vhost->
1209                                                         raw_protocol_index]);
1210                                 lwsl_info("transition to raw vh %s prot %d\n",
1211                                           wsi->vhost->name,
1212                                           wsi->vhost->raw_protocol_index);
1213                                 if ((wsi->protocol->callback)(wsi,
1214                                                 LWS_CALLBACK_RAW_ADOPT,
1215                                                 wsi->user_space, NULL, 0))
1216                                         goto bail_nuke_ah;
1217
1218                                 wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
1219                                 lws_union_transition(wsi, LWSCM_RAW);
1220                                 lws_header_table_detach(wsi, 1);
1221
1222                                 if (m == 2 && (wsi->protocol->callback)(wsi,
1223                                                 LWS_CALLBACK_RAW_RX,
1224                                                 wsi->user_space, obuf, olen))
1225                                         return 1;
1226
1227                                 return 0;
1228                         }
1229                         lwsl_info("lws_parse failed\n");
1230                         goto bail_nuke_ah;
1231                 }
1232
1233                 if (wsi->u.hdr.parser_state != WSI_PARSING_COMPLETE)
1234                         continue;
1235
1236                 lwsl_parser("%s: lws_parse sees parsing complete\n", __func__);
1237                 lwsl_debug("%s: wsi->more_rx_waiting=%d\n", __func__,
1238                                 wsi->more_rx_waiting);
1239
1240                 /* check for unwelcome guests */
1241
1242                 if (wsi->context->reject_service_keywords) {
1243                         const struct lws_protocol_vhost_options *rej =
1244                                         wsi->context->reject_service_keywords;
1245                         char ua[384], *msg = NULL;
1246
1247                         if (lws_hdr_copy(wsi, ua, sizeof(ua) - 1,
1248                                           WSI_TOKEN_HTTP_USER_AGENT) > 0) {
1249                                 ua[sizeof(ua) - 1] = '\0';
1250                                 while (rej) {
1251                                         if (strstr(ua, rej->name)) {
1252                                                 msg = strchr(rej->value, ' ');
1253                                                 if (msg)
1254                                                         msg++;
1255                                                 lws_return_http_status(wsi, atoi(rej->value), msg);
1256
1257                                                 wsi->vhost->conn_stats.rejected++;
1258
1259                                                 goto bail_nuke_ah;
1260                                         }
1261                                         rej = rej->next;
1262                                 }
1263                         }
1264                 }
1265
1266                 /* select vhost */
1267
1268                 if (lws_hdr_total_length(wsi, WSI_TOKEN_HOST)) {
1269                         struct lws_vhost *vhost = lws_select_vhost(
1270                                 context, wsi->vhost->listen_port,
1271                                 lws_hdr_simple_ptr(wsi, WSI_TOKEN_HOST));
1272
1273                         if (vhost)
1274                                 wsi->vhost = vhost;
1275                 } else
1276                         lwsl_info("no host\n");
1277
1278                 wsi->vhost->conn_stats.trans++;
1279                 if (!wsi->conn_stat_done) {
1280                         wsi->vhost->conn_stats.conn++;
1281                         wsi->conn_stat_done = 1;
1282                 }
1283
1284                 if (lws_hdr_total_length(wsi, WSI_TOKEN_CONNECT)) {
1285                         lwsl_info("Changing to RAW mode\n");
1286                         m = 0;
1287                         goto raw_transition;
1288                 }
1289
1290                 wsi->mode = LWSCM_PRE_WS_SERVING_ACCEPT;
1291                 lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
1292
1293                 /* is this websocket protocol or normal http 1.0? */
1294
1295                 if (lws_hdr_total_length(wsi, WSI_TOKEN_UPGRADE)) {
1296                         if (!strcasecmp(lws_hdr_simple_ptr(wsi, WSI_TOKEN_UPGRADE),
1297                                         "websocket")) {
1298                                 wsi->vhost->conn_stats.ws_upg++;
1299                                 lwsl_info("Upgrade to ws\n");
1300                                 goto upgrade_ws;
1301                         }
1302 #ifdef LWS_USE_HTTP2
1303                         if (!strcasecmp(lws_hdr_simple_ptr(wsi, WSI_TOKEN_UPGRADE),
1304                                         "h2c")) {
1305                                 wsi->vhost->conn_stats.http2_upg++;
1306                                 lwsl_info("Upgrade to h2c\n");
1307                                 goto upgrade_h2c;
1308                         }
1309 #endif
1310                         lwsl_info("Unknown upgrade\n");
1311                         /* dunno what he wanted to upgrade to */
1312                         goto bail_nuke_ah;
1313                 }
1314
1315                 /* no upgrade ack... he remained as HTTP */
1316
1317                 lwsl_info("No upgrade\n");
1318                 ah = wsi->u.hdr.ah;
1319
1320                 lws_union_transition(wsi, LWSCM_HTTP_SERVING_ACCEPTED);
1321                 wsi->state = LWSS_HTTP;
1322                 wsi->u.http.fop_fd = NULL;
1323
1324                 /* expose it at the same offset as u.hdr */
1325                 wsi->u.http.ah = ah;
1326                 lwsl_debug("%s: wsi %p: ah %p\n", __func__, (void *)wsi,
1327                            (void *)wsi->u.hdr.ah);
1328
1329                 n = lws_http_action(wsi);
1330
1331                 return n;
1332
1333 #ifdef LWS_USE_HTTP2
1334 upgrade_h2c:
1335                 if (!lws_hdr_total_length(wsi, WSI_TOKEN_HTTP2_SETTINGS)) {
1336                         lwsl_info("missing http2_settings\n");
1337                         goto bail_nuke_ah;
1338                 }
1339
1340                 lwsl_info("h2c upgrade...\n");
1341
1342                 p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP2_SETTINGS);
1343                 /* convert the peer's HTTP-Settings */
1344                 n = lws_b64_decode_string(p, protocol_list,
1345                                           sizeof(protocol_list));
1346                 if (n < 0) {
1347                         lwsl_parser("HTTP2_SETTINGS too long\n");
1348                         return 1;
1349                 }
1350
1351                 /* adopt the header info */
1352
1353                 ah = wsi->u.hdr.ah;
1354
1355                 lws_union_transition(wsi, LWSCM_HTTP2_SERVING);
1356
1357                 /* http2 union member has http union struct at start */
1358                 wsi->u.http.ah = ah;
1359
1360                 lws_http2_init(&wsi->u.http2.peer_settings);
1361                 lws_http2_init(&wsi->u.http2.my_settings);
1362
1363                 /* HTTP2 union */
1364
1365                 lws_http2_interpret_settings_payload(&wsi->u.http2.peer_settings,
1366                                 (unsigned char *)protocol_list, n);
1367
1368                 strcpy(protocol_list,
1369                        "HTTP/1.1 101 Switching Protocols\x0d\x0a"
1370                       "Connection: Upgrade\x0d\x0a"
1371                       "Upgrade: h2c\x0d\x0a\x0d\x0a");
1372                 n = lws_issue_raw(wsi, (unsigned char *)protocol_list,
1373                                         strlen(protocol_list));
1374                 if (n != strlen(protocol_list)) {
1375                         lwsl_debug("http2 switch: ERROR writing to socket\n");
1376                         return 1;
1377                 }
1378
1379                 wsi->state = LWSS_HTTP2_AWAIT_CLIENT_PREFACE;
1380
1381                 return 0;
1382 #endif
1383
1384 upgrade_ws:
1385                 if (!wsi->protocol)
1386                         lwsl_err("NULL protocol at lws_read\n");
1387
1388                 /*
1389                  * It's websocket
1390                  *
1391                  * Select the first protocol we support from the list
1392                  * the client sent us.
1393                  *
1394                  * Copy it to remove header fragmentation
1395                  */
1396
1397                 if (lws_hdr_copy(wsi, protocol_list, sizeof(protocol_list) - 1,
1398                                  WSI_TOKEN_PROTOCOL) < 0) {
1399                         lwsl_err("protocol list too long");
1400                         goto bail_nuke_ah;
1401                 }
1402
1403                 protocol_len = lws_hdr_total_length(wsi, WSI_TOKEN_PROTOCOL);
1404                 protocol_list[protocol_len] = '\0';
1405                 p = protocol_list;
1406                 hit = 0;
1407
1408                 while (*p && !hit) {
1409                         n = 0;
1410                         non_space_char_found = 0;
1411                         while (n < sizeof(protocol_name) - 1 && *p &&
1412                                *p != ',') {
1413                                 // ignore leading spaces
1414                                 if (!non_space_char_found && *p == ' ') {
1415                                         n++;
1416                                         continue;
1417                                 }
1418                                 non_space_char_found = 1;
1419                                 protocol_name[n++] = *p++;
1420                         }
1421                         protocol_name[n] = '\0';
1422                         if (*p)
1423                                 p++;
1424
1425                         lwsl_info("checking %s\n", protocol_name);
1426
1427                         n = 0;
1428                         while (wsi->vhost->protocols[n].callback) {
1429                                 lwsl_info("try %s\n", wsi->vhost->protocols[n].name);
1430
1431                                 if (wsi->vhost->protocols[n].name &&
1432                                     !strcmp(wsi->vhost->protocols[n].name,
1433                                             protocol_name)) {
1434                                         wsi->protocol = &wsi->vhost->protocols[n];
1435                                         hit = 1;
1436                                         break;
1437                                 }
1438
1439                                 n++;
1440                         }
1441                 }
1442
1443                 /* we didn't find a protocol he wanted? */
1444
1445                 if (!hit) {
1446                         if (lws_hdr_simple_ptr(wsi, WSI_TOKEN_PROTOCOL)) {
1447                                 lwsl_info("No protocol from \"%s\" supported\n",
1448                                          protocol_list);
1449                                 goto bail_nuke_ah;
1450                         }
1451                         /*
1452                          * some clients only have one protocol and
1453                          * do not send the protocol list header...
1454                          * allow it and match to the vhost's default
1455                          * protocol (which itself defaults to zero)
1456                          */
1457                         lwsl_info("defaulting to prot handler %d\n",
1458                                 wsi->vhost->default_protocol_index);
1459                         n = 0;
1460                         wsi->protocol = &wsi->vhost->protocols[
1461                                       (int)wsi->vhost->default_protocol_index];
1462                 }
1463
1464                 /* allocate wsi->user storage */
1465                 if (lws_ensure_user_space(wsi))
1466                         goto bail_nuke_ah;
1467
1468                 /*
1469                  * Give the user code a chance to study the request and
1470                  * have the opportunity to deny it
1471                  */
1472                 if ((wsi->protocol->callback)(wsi,
1473                                 LWS_CALLBACK_FILTER_PROTOCOL_CONNECTION,
1474                                 wsi->user_space,
1475                               lws_hdr_simple_ptr(wsi, WSI_TOKEN_PROTOCOL), 0)) {
1476                         lwsl_warn("User code denied connection\n");
1477                         goto bail_nuke_ah;
1478                 }
1479
1480                 /*
1481                  * Perform the handshake according to the protocol version the
1482                  * client announced
1483                  */
1484
1485                 switch (wsi->ietf_spec_revision) {
1486                 case 13:
1487                         lwsl_parser("lws_parse calling handshake_04\n");
1488                         if (handshake_0405(context, wsi)) {
1489                                 lwsl_info("hs0405 has failed the connection\n");
1490                                 goto bail_nuke_ah;
1491                         }
1492                         break;
1493
1494                 default:
1495                         lwsl_info("Unknown client spec version %d\n",
1496                                   wsi->ietf_spec_revision);
1497                         goto bail_nuke_ah;
1498                 }
1499
1500                 lws_same_vh_protocol_insert(wsi, n);
1501
1502                 /* we are upgrading to ws, so http/1.1 and keepalive +
1503                  * pipelined header considerations about keeping the ah around
1504                  * no longer apply.  However it's common for the first ws
1505                  * protocol data to have been coalesced with the browser
1506                  * upgrade request and to already be in the ah rx buffer.
1507                  */
1508
1509                 lwsl_info("%s: %p: inheriting ah in ws mode (rxpos:%d, rxlen:%d)\n",
1510                           __func__, wsi, wsi->u.hdr.ah->rxpos,
1511                           wsi->u.hdr.ah->rxlen);
1512                 lws_pt_lock(pt);
1513                 hdr = wsi->u.hdr;
1514
1515                 lws_union_transition(wsi, LWSCM_WS_SERVING);
1516                 /*
1517                  * first service is WS mode will notice this, use the RX and
1518                  * then detach the ah (caution: we are not in u.hdr union
1519                  * mode any more then... ah_temp member is at start the same
1520                  * though)
1521                  *
1522                  * Because rxpos/rxlen shows something in the ah, we will get
1523                  * service guaranteed next time around the event loop
1524                  *
1525                  * All union members begin with hdr, so we can use it even
1526                  * though we transitioned to ws union mode (the ah detach
1527                  * code uses it anyway).
1528                  */
1529                 wsi->u.hdr = hdr;
1530                 lws_pt_unlock(pt);
1531
1532                 lws_restart_ws_ping_pong_timer(wsi);
1533
1534                 /*
1535                  * create the frame buffer for this connection according to the
1536                  * size mentioned in the protocol definition.  If 0 there, use
1537                  * a big default for compatibility
1538                  */
1539
1540                 n = wsi->protocol->rx_buffer_size;
1541                 if (!n)
1542                         n = context->pt_serv_buf_size;
1543                 n += LWS_PRE;
1544                 wsi->u.ws.rx_ubuf = lws_malloc(n + 4 /* 0x0000ffff zlib */);
1545                 if (!wsi->u.ws.rx_ubuf) {
1546                         lwsl_err("Out of Mem allocating rx buffer %d\n", n);
1547                         return 1;
1548                 }
1549                 wsi->u.ws.rx_ubuf_alloc = n;
1550                 lwsl_debug("Allocating RX buffer %d\n", n);
1551 #if LWS_POSIX && !defined(LWS_WITH_ESP32)
1552                 if (setsockopt(wsi->desc.sockfd, SOL_SOCKET, SO_SNDBUF,
1553                                (const char *)&n, sizeof n)) {
1554                         lwsl_warn("Failed to set SNDBUF to %d", n);
1555                         return 1;
1556                 }
1557 #endif
1558
1559                 lwsl_parser("accepted v%02d connection\n",
1560                             wsi->ietf_spec_revision);
1561
1562                 /* notify user code that we're ready to roll */
1563
1564                 if (wsi->protocol->callback)
1565                         if (wsi->protocol->callback(wsi, LWS_CALLBACK_ESTABLISHED,
1566                                                     wsi->user_space,
1567 #ifdef LWS_OPENSSL_SUPPORT
1568                                                     wsi->ssl,
1569 #else
1570                                                     NULL,
1571 #endif
1572                                                     0))
1573                                 return 1;
1574
1575                 /* !!! drop ah unreservedly after ESTABLISHED */
1576                 if (!wsi->more_rx_waiting) {
1577                         wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
1578
1579                         //lwsl_notice("%p: dropping ah EST\n", wsi);
1580                         lws_header_table_detach(wsi, 1);
1581                 }
1582
1583                 return 0;
1584         } /* while all chars are handled */
1585
1586         return 0;
1587
1588 bail_nuke_ah:
1589         /* drop the header info */
1590         /* we're closing, losing some rx is OK */
1591         wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
1592         //lwsl_notice("%s: drop2\n", __func__);
1593         lws_header_table_detach(wsi, 1);
1594
1595         return 1;
1596 }
1597
1598 static int
1599 lws_get_idlest_tsi(struct lws_context *context)
1600 {
1601         unsigned int lowest = ~0;
1602         int n = 0, hit = -1;
1603
1604         for (; n < context->count_threads; n++) {
1605                 if ((unsigned int)context->pt[n].fds_count !=
1606                     context->fd_limit_per_thread - 1 &&
1607                     (unsigned int)context->pt[n].fds_count < lowest) {
1608                         lowest = context->pt[n].fds_count;
1609                         hit = n;
1610                 }
1611         }
1612
1613         return hit;
1614 }
1615
1616 struct lws *
1617 lws_create_new_server_wsi(struct lws_vhost *vhost)
1618 {
1619         struct lws *new_wsi;
1620         int n = lws_get_idlest_tsi(vhost->context);
1621
1622         if (n < 0) {
1623                 lwsl_err("no space for new conn\n");
1624                 return NULL;
1625         }
1626
1627         new_wsi = lws_zalloc(sizeof(struct lws));
1628         if (new_wsi == NULL) {
1629                 lwsl_err("Out of memory for new connection\n");
1630                 return NULL;
1631         }
1632
1633         new_wsi->tsi = n;
1634         lwsl_debug("Accepted wsi %p to context %p, tsi %d\n", new_wsi,
1635                     vhost->context, new_wsi->tsi);
1636
1637         new_wsi->vhost = vhost;
1638         new_wsi->context = vhost->context;
1639         new_wsi->pending_timeout = NO_PENDING_TIMEOUT;
1640         new_wsi->rxflow_change_to = LWS_RXFLOW_ALLOW;
1641
1642         /* initialize the instance struct */
1643
1644         new_wsi->state = LWSS_HTTP;
1645         new_wsi->mode = LWSCM_HTTP_SERVING;
1646         new_wsi->hdr_parsing_completed = 0;
1647
1648 #ifdef LWS_OPENSSL_SUPPORT
1649         new_wsi->use_ssl = LWS_SSL_ENABLED(vhost);
1650 #endif
1651
1652         /*
1653          * these can only be set once the protocol is known
1654          * we set an unestablished connection's protocol pointer
1655          * to the start of the supported list, so it can look
1656          * for matching ones during the handshake
1657          */
1658         new_wsi->protocol = vhost->protocols;
1659         new_wsi->user_space = NULL;
1660         new_wsi->ietf_spec_revision = 0;
1661         new_wsi->desc.sockfd = LWS_SOCK_INVALID;
1662         vhost->context->count_wsi_allocated++;
1663
1664         /*
1665          * outermost create notification for wsi
1666          * no user_space because no protocol selection
1667          */
1668         vhost->protocols[0].callback(new_wsi, LWS_CALLBACK_WSI_CREATE,
1669                                        NULL, NULL, 0);
1670
1671         return new_wsi;
1672 }
1673
1674 LWS_VISIBLE int LWS_WARN_UNUSED_RESULT
1675 lws_http_transaction_completed(struct lws *wsi)
1676 {
1677         int n = NO_PENDING_TIMEOUT;
1678
1679         lws_access_log(wsi);
1680
1681         lwsl_info("%s: wsi %p\n", __func__, wsi);
1682         /* if we can't go back to accept new headers, drop the connection */
1683         if (wsi->u.http.connection_type != HTTP_CONNECTION_KEEP_ALIVE) {
1684                 lwsl_info("%s: %p: close connection\n", __func__, wsi);
1685                 return 1;
1686         }
1687
1688         if (lws_bind_protocol(wsi, &wsi->vhost->protocols[0]))
1689                 return 1;
1690
1691         /* otherwise set ourselves up ready to go again */
1692         wsi->state = LWSS_HTTP;
1693         wsi->mode = LWSCM_HTTP_SERVING;
1694         wsi->u.http.content_length = 0;
1695         wsi->u.http.content_remain = 0;
1696         wsi->hdr_parsing_completed = 0;
1697 #ifdef LWS_WITH_ACCESS_LOG
1698         wsi->access_log.sent = 0;
1699 #endif
1700
1701         if (wsi->vhost->keepalive_timeout)
1702                 n = PENDING_TIMEOUT_HTTP_KEEPALIVE_IDLE;
1703         lws_set_timeout(wsi, n, wsi->vhost->keepalive_timeout);
1704
1705         /*
1706          * We already know we are on http1.1 / keepalive and the next thing
1707          * coming will be another header set.
1708          *
1709          * If there is no pending rx and we still have the ah, drop it and
1710          * reacquire a new ah when the new headers start to arrive.  (Otherwise
1711          * we needlessly hog an ah indefinitely.)
1712          *
1713          * However if there is pending rx and we know from the keepalive state
1714          * that is already at least the start of another header set, simply
1715          * reset the existing header table and keep it.
1716          */
1717         if (wsi->u.hdr.ah) {
1718                 lwsl_info("%s: wsi->more_rx_waiting=%d\n", __func__,
1719                                 wsi->more_rx_waiting);
1720
1721                 if (!wsi->more_rx_waiting) {
1722                         wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
1723                         lws_header_table_detach(wsi, 1);
1724 #ifdef LWS_OPENSSL_SUPPORT
1725                         /*
1726                          * additionally... if we are hogging an SSL instance
1727                          * with no pending pipelined headers (or ah now), and
1728                          * SSL is scarce, drop this connection without waiting
1729                          */
1730
1731                         if (wsi->vhost->use_ssl &&
1732                             wsi->context->simultaneous_ssl_restriction &&
1733                             wsi->context->simultaneous_ssl ==
1734                                    wsi->context->simultaneous_ssl_restriction) {
1735                                 lwsl_info("%s: simultaneous_ssl_restriction and nothing pipelined\n", __func__);
1736                                 return 1;
1737                         }
1738 #endif
1739                 } else
1740                         lws_header_table_reset(wsi, 1);
1741         }
1742
1743         /* If we're (re)starting on headers, need other implied init */
1744         wsi->u.hdr.ues = URIES_IDLE;
1745
1746         lwsl_info("%s: %p: keep-alive await new transaction\n", __func__, wsi);
1747
1748         return 0;
1749 }
1750
1751 /* if not a socket, it's a raw, non-ssl file descriptor */
1752
1753 LWS_VISIBLE struct lws *
1754 lws_adopt_descriptor_vhost(struct lws_vhost *vh, lws_adoption_type type,
1755                            lws_sock_file_fd_type fd, const char *vh_prot_name,
1756                            struct lws *parent)
1757 {
1758         struct lws_context *context = vh->context;
1759         struct lws *new_wsi = lws_create_new_server_wsi(vh);
1760         int n, ssl = 0;
1761
1762         if (!new_wsi) {
1763                 if (type & LWS_ADOPT_SOCKET)
1764                         compatible_close(fd.sockfd);
1765                 return NULL;
1766         }
1767
1768         if (parent) {
1769                 new_wsi->parent = parent;
1770                 new_wsi->sibling_list = parent->child_list;
1771                 parent->child_list = new_wsi;
1772         }
1773
1774         new_wsi->desc = fd;
1775
1776         if (vh_prot_name) {
1777                 new_wsi->protocol = lws_vhost_name_to_protocol(new_wsi->vhost,
1778                                                                vh_prot_name);
1779                 if (!new_wsi->protocol) {
1780                         lwsl_err("Protocol %s not enabled on vhost %s\n",
1781                                  vh_prot_name, new_wsi->vhost->name);
1782                         goto bail;
1783                 }
1784                 if (lws_ensure_user_space(new_wsi))
1785                         goto bail;
1786         } else
1787                 if (type & LWS_ADOPT_HTTP) /* he will transition later */
1788                         new_wsi->protocol =
1789                                 &vh->protocols[vh->default_protocol_index];
1790                 else { /* this is the only time he will transition */
1791                         lws_bind_protocol(new_wsi,
1792                                 &vh->protocols[vh->raw_protocol_index]);
1793                         lws_union_transition(new_wsi, LWSCM_RAW);
1794                 }
1795
1796         if (type & LWS_ADOPT_SOCKET) { /* socket desc */
1797                 lwsl_debug("%s: new wsi %p, sockfd %d\n", __func__, new_wsi,
1798                            (int)(size_t)fd.sockfd);
1799
1800                 if (type & LWS_ADOPT_HTTP)
1801                         /* the transport is accepted...
1802                          * give him time to negotiate */
1803                         lws_set_timeout(new_wsi,
1804                                         PENDING_TIMEOUT_ESTABLISH_WITH_SERVER,
1805                                         context->timeout_secs);
1806
1807 #if LWS_POSIX == 0
1808 #if defined(LWS_WITH_ESP8266)
1809                 esp8266_tcp_stream_accept(accept_fd, new_wsi);
1810 #endif
1811 #endif
1812         } else /* file desc */
1813                 lwsl_debug("%s: new wsi %p, filefd %d\n", __func__, new_wsi,
1814                            (int)(size_t)fd.filefd);
1815
1816         /*
1817          * A new connection was accepted. Give the user a chance to
1818          * set properties of the newly created wsi. There's no protocol
1819          * selected yet so we issue this to the vhosts's default protocol,
1820          * itself by default protocols[0]
1821          */
1822         n = LWS_CALLBACK_SERVER_NEW_CLIENT_INSTANTIATED;
1823         if (!(type & LWS_ADOPT_HTTP)) {
1824                 if (!(type & LWS_ADOPT_SOCKET))
1825                         n = LWS_CALLBACK_RAW_ADOPT_FILE;
1826                 else
1827                         n = LWS_CALLBACK_RAW_ADOPT;
1828         }
1829
1830         if (!LWS_SSL_ENABLED(new_wsi->vhost) || !(type & LWS_ADOPT_ALLOW_SSL) ||
1831             !(type & LWS_ADOPT_SOCKET)) {
1832                 /* non-SSL */
1833                 if (!(type & LWS_ADOPT_HTTP)) {
1834                         if (!(type & LWS_ADOPT_SOCKET))
1835                                 new_wsi->mode = LWSCM_RAW_FILEDESC;
1836                         else
1837                                 new_wsi->mode = LWSCM_RAW;
1838                 }
1839         } else {
1840                 /* SSL */
1841                 if (!(type & LWS_ADOPT_HTTP))
1842                         new_wsi->mode = LWSCM_SSL_INIT_RAW;
1843                 else
1844                         new_wsi->mode = LWSCM_SSL_INIT;
1845
1846                 ssl = 1;
1847         }
1848
1849         lws_libev_accept(new_wsi, new_wsi->desc);
1850         lws_libuv_accept(new_wsi, new_wsi->desc);
1851         lws_libevent_accept(new_wsi, new_wsi->desc);
1852
1853         if (!ssl) {
1854                 if (insert_wsi_socket_into_fds(context, new_wsi)) {
1855                         lwsl_err("%s: fail inserting socket\n", __func__);
1856                         goto fail;
1857                 }
1858         } else
1859                 if (lws_server_socket_service_ssl(new_wsi, fd.sockfd)) {
1860                         lwsl_err("%s: fail ssl negotiation\n", __func__);
1861                         goto fail;
1862                 }
1863
1864         /*
1865          *  by deferring callback to this point, after insertion to fds,
1866          * lws_callback_on_writable() can work from the callback
1867          */
1868         if ((new_wsi->protocol->callback)(
1869                         new_wsi, n, new_wsi->user_space, NULL, 0))
1870                 goto fail;
1871
1872         if (type & LWS_ADOPT_HTTP)
1873                 if (!lws_header_table_attach(new_wsi, 0))
1874                         lwsl_debug("Attached ah immediately\n");
1875
1876         return new_wsi;
1877
1878 fail:
1879         if (type & LWS_ADOPT_SOCKET)
1880                 lws_close_free_wsi(new_wsi, LWS_CLOSE_STATUS_NOSTATUS);
1881
1882         return NULL;
1883
1884 bail:
1885         if (parent)
1886                 parent->child_list = new_wsi->sibling_list;
1887         if (new_wsi->user_space)
1888                 lws_free(new_wsi->user_space);
1889         lws_free(new_wsi);
1890
1891         return NULL;
1892 }
1893
1894 LWS_VISIBLE struct lws *
1895 lws_adopt_socket_vhost(struct lws_vhost *vh, lws_sockfd_type accept_fd)
1896 {
1897         lws_sock_file_fd_type fd;
1898
1899         fd.sockfd = accept_fd;
1900         return lws_adopt_descriptor_vhost(vh, LWS_ADOPT_SOCKET |
1901                         LWS_ADOPT_HTTP | LWS_ADOPT_ALLOW_SSL, fd, NULL, NULL);
1902 }
1903
1904 LWS_VISIBLE struct lws *
1905 lws_adopt_socket(struct lws_context *context, lws_sockfd_type accept_fd)
1906 {
1907         return lws_adopt_socket_vhost(context->vhost_list, accept_fd);
1908 }
1909
1910 /* Common read-buffer adoption for lws_adopt_*_readbuf */
1911 static struct lws*
1912 adopt_socket_readbuf(struct lws *wsi, const char *readbuf, size_t len)
1913 {
1914         struct lws_context_per_thread *pt;
1915         struct allocated_headers *ah;
1916         struct lws_pollfd *pfd;
1917
1918         if (!wsi)
1919                 return NULL;
1920
1921         if (!readbuf || len == 0)
1922                 return wsi;
1923
1924         if (len > sizeof(ah->rx)) {
1925                 lwsl_err("%s: rx in too big\n", __func__);
1926                 goto bail;
1927         }
1928
1929         /*
1930          * we can't process the initial read data until we can attach an ah.
1931          *
1932          * if one is available, get it and place the data in his ah rxbuf...
1933          * wsi with ah that have pending rxbuf get auto-POLLIN service.
1934          *
1935          * no autoservice because we didn't get a chance to attach the
1936          * readbuf data to wsi or ah yet, and we will do it next if we get
1937          * the ah.
1938          */
1939         if (wsi->u.hdr.ah || !lws_header_table_attach(wsi, 0)) {
1940                 ah = wsi->u.hdr.ah;
1941                 memcpy(ah->rx, readbuf, len);
1942                 ah->rxpos = 0;
1943                 ah->rxlen = len;
1944
1945                 lwsl_notice("%s: calling service on readbuf ah\n", __func__);
1946                 pt = &wsi->context->pt[(int)wsi->tsi];
1947
1948                 /* unlike a normal connect, we have the headers already
1949                  * (or the first part of them anyway).
1950                  * libuv won't come back and service us without a network
1951                  * event, so we need to do the header service right here.
1952                  */
1953                 pfd = &pt->fds[wsi->position_in_fds_table];
1954                 pfd->revents |= LWS_POLLIN;
1955                 lwsl_err("%s: calling service\n", __func__);
1956                 if (lws_service_fd_tsi(wsi->context, pfd, wsi->tsi))
1957                         /* service closed us */
1958                         return NULL;
1959
1960                 return wsi;
1961         }
1962         lwsl_err("%s: deferring handling ah\n", __func__);
1963         /*
1964          * hum if no ah came, we are on the wait list and must defer
1965          * dealing with this until the ah arrives.
1966          *
1967          * later successful lws_header_table_attach() will apply the
1968          * below to the rx buffer (via lws_header_table_reset()).
1969          */
1970         wsi->u.hdr.preamble_rx = lws_malloc(len);
1971         if (!wsi->u.hdr.preamble_rx) {
1972                 lwsl_err("OOM\n");
1973                 goto bail;
1974         }
1975         memcpy(wsi->u.hdr.preamble_rx, readbuf, len);
1976         wsi->u.hdr.preamble_rx_len = len;
1977
1978         return wsi;
1979
1980 bail:
1981         lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
1982
1983         return NULL;
1984 }
1985
1986 LWS_VISIBLE struct lws *
1987 lws_adopt_socket_readbuf(struct lws_context *context, lws_sockfd_type accept_fd,
1988                          const char *readbuf, size_t len)
1989 {
1990         return adopt_socket_readbuf(lws_adopt_socket(context, accept_fd), readbuf, len);
1991 }
1992
1993 LWS_VISIBLE struct lws *
1994 lws_adopt_socket_vhost_readbuf(struct lws_vhost *vhost, lws_sockfd_type accept_fd,
1995                          const char *readbuf, size_t len)
1996 {
1997         return adopt_socket_readbuf(lws_adopt_socket_vhost(vhost, accept_fd), readbuf, len);
1998 }
1999
2000 LWS_VISIBLE int
2001 lws_server_socket_service(struct lws_context *context, struct lws *wsi,
2002                           struct lws_pollfd *pollfd)
2003 {
2004         struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
2005         lws_sockfd_type accept_fd = LWS_SOCK_INVALID;
2006         struct allocated_headers *ah;
2007         lws_sock_file_fd_type fd;
2008         int opts = LWS_ADOPT_SOCKET | LWS_ADOPT_ALLOW_SSL;
2009 #if LWS_POSIX
2010         struct sockaddr_in cli_addr;
2011         socklen_t clilen;
2012 #endif
2013         int n, len;
2014
2015         // lwsl_notice("%s: mode %d\n", __func__, wsi->mode);
2016
2017         switch (wsi->mode) {
2018
2019         case LWSCM_HTTP_SERVING:
2020         case LWSCM_HTTP_SERVING_ACCEPTED:
2021         case LWSCM_HTTP2_SERVING:
2022         case LWSCM_RAW:
2023
2024                 /* handle http headers coming in */
2025
2026                 /* pending truncated sends have uber priority */
2027
2028                 if (wsi->trunc_len) {
2029                         if (!(pollfd->revents & LWS_POLLOUT))
2030                                 break;
2031
2032                         if (lws_issue_raw(wsi, wsi->trunc_alloc +
2033                                                wsi->trunc_offset,
2034                                           wsi->trunc_len) < 0)
2035                                 goto fail;
2036                         /*
2037                          * we can't afford to allow input processing to send
2038                          * something new, so spin around he event loop until
2039                          * he doesn't have any partials
2040                          */
2041                         break;
2042                 }
2043
2044                 /* any incoming data ready? */
2045
2046                 if (!(pollfd->revents & pollfd->events & LWS_POLLIN))
2047                         goto try_pollout;
2048
2049                 /*
2050                  * If we previously just did POLLIN when IN and OUT were
2051                  * signalled (because POLLIN processing may have used up
2052                  * the POLLOUT), don't let that happen twice in a row...
2053                  * next time we see the situation favour POLLOUT
2054                  */
2055 #if !defined(LWS_WITH_ESP8266)
2056                 if (wsi->favoured_pollin &&
2057                     (pollfd->revents & pollfd->events & LWS_POLLOUT)) {
2058                         wsi->favoured_pollin = 0;
2059                         goto try_pollout;
2060                 }
2061 #endif
2062
2063                 /* these states imply we MUST have an ah attached */
2064
2065                 if (wsi->mode != LWSCM_RAW && (wsi->state == LWSS_HTTP ||
2066                     wsi->state == LWSS_HTTP_ISSUING_FILE ||
2067                     wsi->state == LWSS_HTTP_HEADERS)) {
2068                         if (!wsi->u.hdr.ah) {
2069
2070                                 //lwsl_err("wsi %p: missing ah\n", wsi);
2071                                 /* no autoservice beacuse we will do it next */
2072                                 if (lws_header_table_attach(wsi, 0)) {
2073                                         lwsl_info("wsi %p: failed to acquire ah\n", wsi);
2074                                         goto try_pollout;
2075                                 }
2076                         }
2077                         ah = wsi->u.hdr.ah;
2078
2079                         //lwsl_notice("%s: %p: rxpos:%d rxlen:%d\n", __func__, wsi,
2080                         //         ah->rxpos, ah->rxlen);
2081
2082                         /* if nothing in ah rx buffer, get some fresh rx */
2083                         if (ah->rxpos == ah->rxlen) {
2084                                 ah->rxlen = lws_ssl_capable_read(wsi, ah->rx,
2085                                                    sizeof(ah->rx));
2086                                 ah->rxpos = 0;
2087                                 //lwsl_notice("%s: wsi %p, ah->rxlen = %d\r\n",
2088                                 //         __func__, wsi, ah->rxlen);
2089                                 switch (ah->rxlen) {
2090                                 case 0:
2091                                         lwsl_info("%s: read 0 len\n", __func__);
2092                                         /* lwsl_info("   state=%d\n", wsi->state); */
2093 //                                      if (!wsi->hdr_parsing_completed)
2094 //                                              lws_header_table_detach(wsi);
2095                                         /* fallthru */
2096                                 case LWS_SSL_CAPABLE_ERROR:
2097                                         goto fail;
2098                                 case LWS_SSL_CAPABLE_MORE_SERVICE:
2099                                         ah->rxlen = ah->rxpos = 0;
2100                                         goto try_pollout;
2101                                 }
2102                         }
2103
2104                         if (!(ah->rxpos != ah->rxlen && ah->rxlen)) {
2105                                 lwsl_err("%s: assert: rxpos %d, rxlen %d\n",
2106                                          __func__, ah->rxpos, ah->rxlen);
2107
2108                                 assert(0);
2109                         }
2110
2111                         /* just ignore incoming if waiting for close */
2112                         if (wsi->state != LWSS_FLUSHING_STORED_SEND_BEFORE_CLOSE) {
2113                                 n = lws_read(wsi, ah->rx + ah->rxpos,
2114                                              ah->rxlen - ah->rxpos);
2115                                 if (n < 0) /* we closed wsi */
2116                                         return 1;
2117                                 if (wsi->u.hdr.ah) {
2118                                         if ( wsi->u.hdr.ah->rxlen)
2119                                                  wsi->u.hdr.ah->rxpos += n;
2120
2121                                         lwsl_debug("%s: wsi %p: ah read rxpos %d, rxlen %d\n", __func__, wsi, wsi->u.hdr.ah->rxpos, wsi->u.hdr.ah->rxlen);
2122
2123                                         if (wsi->u.hdr.ah->rxpos == wsi->u.hdr.ah->rxlen &&
2124                                             (wsi->mode != LWSCM_HTTP_SERVING &&
2125                                              wsi->mode != LWSCM_HTTP_SERVING_ACCEPTED &&
2126                                              wsi->mode != LWSCM_HTTP2_SERVING))
2127                                                 lws_header_table_detach(wsi, 1);
2128                                 }
2129                                 break;
2130                         }
2131
2132                         goto try_pollout;
2133                 }
2134
2135                 len = lws_ssl_capable_read(wsi, pt->serv_buf,
2136                                            context->pt_serv_buf_size);
2137                 lwsl_debug("%s: wsi %p read %d\r\n", __func__, wsi, len);
2138                 switch (len) {
2139                 case 0:
2140                         lwsl_info("%s: read 0 len\n", __func__);
2141                         /* lwsl_info("   state=%d\n", wsi->state); */
2142 //                      if (!wsi->hdr_parsing_completed)
2143 //                              lws_header_table_detach(wsi);
2144                         /* fallthru */
2145                 case LWS_SSL_CAPABLE_ERROR:
2146                         goto fail;
2147                 case LWS_SSL_CAPABLE_MORE_SERVICE:
2148                         goto try_pollout;
2149                 }
2150
2151                 if (wsi->mode == LWSCM_RAW) {
2152                         n = user_callback_handle_rxflow(wsi->protocol->callback,
2153                                         wsi, LWS_CALLBACK_RAW_RX,
2154                                         wsi->user_space, pt->serv_buf, len);
2155                         if (n < 0) {
2156                                 lwsl_info("LWS_CALLBACK_RAW_RX_fail\n");
2157                                 goto fail;
2158                         }
2159                         goto try_pollout;
2160                 }
2161
2162                 /* just ignore incoming if waiting for close */
2163                 if (wsi->state != LWSS_FLUSHING_STORED_SEND_BEFORE_CLOSE) {
2164                         /*
2165                          * this may want to send
2166                          * (via HTTP callback for example)
2167                          */
2168                         n = lws_read(wsi, pt->serv_buf, len);
2169                         if (n < 0) /* we closed wsi */
2170                                 return 1;
2171                         /*
2172                          *  he may have used up the
2173                          * writability above, if we will defer POLLOUT
2174                          * processing in favour of POLLIN, note it
2175                          */
2176                         if (pollfd->revents & LWS_POLLOUT)
2177                                 wsi->favoured_pollin = 1;
2178                         break;
2179                 }
2180
2181 try_pollout:
2182
2183                 /* this handles POLLOUT for http serving fragments */
2184
2185                 if (!(pollfd->revents & LWS_POLLOUT))
2186                         break;
2187
2188                 /* one shot */
2189                 if (lws_change_pollfd(wsi, LWS_POLLOUT, 0)) {
2190                         lwsl_notice("%s a\n", __func__);
2191                         goto fail;
2192                 }
2193
2194                 if (wsi->mode == LWSCM_RAW) {
2195                         n = user_callback_handle_rxflow(wsi->protocol->callback,
2196                                         wsi, LWS_CALLBACK_RAW_WRITEABLE,
2197                                         wsi->user_space, NULL, 0);
2198                         if (n < 0) {
2199                                 lwsl_info("writeable_fail\n");
2200                                 goto fail;
2201                         }
2202                         break;
2203                 }
2204
2205                 if (!wsi->hdr_parsing_completed)
2206                         break;
2207
2208                 if (wsi->state != LWSS_HTTP_ISSUING_FILE) {
2209                         n = user_callback_handle_rxflow(wsi->protocol->callback,
2210                                         wsi, LWS_CALLBACK_HTTP_WRITEABLE,
2211                                         wsi->user_space, NULL, 0);
2212                         if (n < 0) {
2213                                 lwsl_info("writeable_fail\n");
2214                                 goto fail;
2215                         }
2216                         break;
2217                 }
2218
2219                 /* >0 == completion, <0 == error */
2220                 n = lws_serve_http_file_fragment(wsi);
2221                 if (n < 0 || (n > 0 && lws_http_transaction_completed(wsi))) {
2222                         lwsl_info("completed\n");
2223                         goto fail;
2224                 }
2225
2226                 break;
2227
2228         case LWSCM_SERVER_LISTENER:
2229
2230 #if LWS_POSIX
2231                 /* pollin means a client has connected to us then */
2232
2233                 do {
2234                         if (!(pollfd->revents & LWS_POLLIN) || !(pollfd->events & LWS_POLLIN))
2235                                 break;
2236
2237 #ifdef LWS_OPENSSL_SUPPORT
2238                         /*
2239                          * can we really accept it, with regards to SSL limit?
2240                          * another vhost may also have had POLLIN on his listener this
2241                          * round and used it up already
2242                          */
2243
2244                         if (wsi->vhost->use_ssl &&
2245                             context->simultaneous_ssl_restriction &&
2246                             context->simultaneous_ssl ==
2247                                           context->simultaneous_ssl_restriction)
2248                                 /* no... ignore it, he won't come again until we are
2249                                  * below the simultaneous_ssl_restriction limit and
2250                                  * POLLIN is enabled on him again
2251                                  */
2252                                 break;
2253 #endif
2254                         /* listen socket got an unencrypted connection... */
2255
2256                         clilen = sizeof(cli_addr);
2257                         lws_latency_pre(context, wsi);
2258                         accept_fd  = accept(pollfd->fd, (struct sockaddr *)&cli_addr,
2259                                             &clilen);
2260                         lws_latency(context, wsi, "listener accept", accept_fd,
2261                                     accept_fd >= 0);
2262                         if (accept_fd < 0) {
2263                                 if (LWS_ERRNO == LWS_EAGAIN ||
2264                                     LWS_ERRNO == LWS_EWOULDBLOCK) {
2265 //                                      lwsl_err("accept asks to try again\n");
2266                                         break;
2267                                 }
2268                                 lwsl_err("ERROR on accept: %s\n", strerror(LWS_ERRNO));
2269                                 break;
2270                         }
2271
2272                         lws_plat_set_socket_options(wsi->vhost, accept_fd);
2273
2274                         lwsl_debug("accepted new conn  port %u on fd=%d\n",
2275                                           ntohs(cli_addr.sin_port), accept_fd);
2276
2277 #else
2278                         /* not very beautiful... */
2279                         accept_fd = (lws_sockfd_type)pollfd;
2280 #endif
2281                         /*
2282                          * look at who we connected to and give user code a chance
2283                          * to reject based on client IP.  There's no protocol selected
2284                          * yet so we issue this to protocols[0]
2285                          */
2286                         if ((wsi->vhost->protocols[0].callback)(wsi,
2287                                         LWS_CALLBACK_FILTER_NETWORK_CONNECTION,
2288                                         NULL, (void *)(long)accept_fd, 0)) {
2289                                 lwsl_debug("Callback denied network connection\n");
2290                                 compatible_close(accept_fd);
2291                                 break;
2292                         }
2293
2294                         if (!(wsi->vhost->options & LWS_SERVER_OPTION_ONLY_RAW))
2295                                 opts |= LWS_ADOPT_HTTP;
2296
2297                         fd.sockfd = accept_fd;
2298                         if (!lws_adopt_descriptor_vhost(wsi->vhost, opts, fd,
2299                                                         NULL, NULL))
2300                                 /* already closed cleanly as necessary */
2301                                 return 1;
2302
2303 #if LWS_POSIX
2304                 } while (pt->fds_count < context->fd_limit_per_thread - 1 &&
2305                          lws_poll_listen_fd(&pt->fds[wsi->position_in_fds_table]) > 0);
2306 #endif
2307                 return 0;
2308
2309         default:
2310                 break;
2311         }
2312
2313         if (!lws_server_socket_service_ssl(wsi, accept_fd))
2314                 return 0;
2315
2316 fail:
2317         lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
2318
2319         return 1;
2320 }
2321
2322 LWS_VISIBLE int
2323 lws_serve_http_file(struct lws *wsi, const char *file, const char *content_type,
2324                     const char *other_headers, int other_headers_len)
2325 {
2326         static const char * const intermediates[] = { "private", "public" };
2327         struct lws_context *context = lws_get_context(wsi);
2328         struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
2329 #if defined(LWS_WITH_RANGES)
2330         struct lws_range_parsing *rp = &wsi->u.http.range;
2331 #endif
2332         char cache_control[50], *cc = "no-store";
2333         unsigned char *response = pt->serv_buf + LWS_PRE;
2334         unsigned char *p = response;
2335         unsigned char *end = p + context->pt_serv_buf_size - LWS_PRE;
2336         unsigned long computed_total_content_length;
2337         int ret = 0, cclen = 8, n = HTTP_STATUS_OK;
2338         lws_fop_flags_t fflags = LWS_O_RDONLY;
2339 #if defined(LWS_WITH_RANGES)
2340         int ranges;
2341 #endif
2342         const struct lws_plat_file_ops *fops;
2343         const char *vpath;
2344
2345         /*
2346          * We either call the platform fops .open with first arg platform fops,
2347          * or we call fops_zip .open with first arg platform fops, and fops_zip
2348          * open will decide whether to switch to fops_zip or stay with fops_def.
2349          *
2350          * If wsi->u.http.fop_fd is already set, the caller already opened it
2351          */
2352         if (!wsi->u.http.fop_fd) {
2353                 fops = lws_vfs_select_fops(wsi->context->fops, file, &vpath);
2354                 fflags |= lws_vfs_prepare_flags(wsi);
2355                 wsi->u.http.fop_fd = fops->LWS_FOP_OPEN(wsi->context->fops,
2356                                                         file, vpath, &fflags);
2357                 if (!wsi->u.http.fop_fd) {
2358                         lwsl_err("Unable to open '%s'\n", file);
2359
2360                         return -1;
2361                 }
2362         }
2363         wsi->u.http.filelen = lws_vfs_get_length(wsi->u.http.fop_fd);
2364         computed_total_content_length = wsi->u.http.filelen;
2365
2366 #if defined(LWS_WITH_RANGES)
2367         ranges = lws_ranges_init(wsi, rp, wsi->u.http.filelen);
2368
2369         lwsl_debug("Range count %d\n", ranges);
2370         /*
2371          * no ranges -> 200;
2372          *  1 range  -> 206 + Content-Type: normal; Content-Range;
2373          *  more     -> 206 + Content-Type: multipart/byteranges
2374          *              Repeat the true Content-Type in each multipart header
2375          *              along with Content-Range
2376          */
2377         if (ranges < 0) {
2378                 /* it means he expressed a range in Range:, but it was illegal */
2379                 lws_return_http_status(wsi, HTTP_STATUS_REQ_RANGE_NOT_SATISFIABLE, NULL);
2380                 if (lws_http_transaction_completed(wsi))
2381                         return -1; /* <0 means just hang up */
2382
2383                 lws_vfs_file_close(&wsi->u.http.fop_fd);
2384
2385                 return 0; /* == 0 means we dealt with the transaction complete */
2386         }
2387         if (ranges)
2388                 n = HTTP_STATUS_PARTIAL_CONTENT;
2389 #endif
2390
2391         if (lws_add_http_header_status(wsi, n, &p, end))
2392                 return -1;
2393
2394         if ((wsi->u.http.fop_fd->flags & (LWS_FOP_FLAG_COMPR_ACCEPTABLE_GZIP |
2395                        LWS_FOP_FLAG_COMPR_IS_GZIP)) ==
2396             (LWS_FOP_FLAG_COMPR_ACCEPTABLE_GZIP | LWS_FOP_FLAG_COMPR_IS_GZIP)) {
2397                 if (lws_add_http_header_by_token(wsi,
2398                         WSI_TOKEN_HTTP_CONTENT_ENCODING,
2399                         (unsigned char *)"gzip", 4, &p, end))
2400                         return -1;
2401                 lwsl_info("file is being provided in gzip\n");
2402         }
2403
2404 #if defined(LWS_WITH_RANGES)
2405         if (ranges < 2 && content_type && content_type[0])
2406                 if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_CONTENT_TYPE,
2407                                                  (unsigned char *)content_type,
2408                                                  strlen(content_type), &p, end))
2409                         return -1;
2410
2411         if (ranges >= 2) { /* multipart byteranges */
2412                 strncpy(wsi->u.http.multipart_content_type, content_type,
2413                         sizeof(wsi->u.http.multipart_content_type) - 1);
2414                 wsi->u.http.multipart_content_type[
2415                          sizeof(wsi->u.http.multipart_content_type) - 1] = '\0';
2416                 if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_CONTENT_TYPE,
2417                                                  (unsigned char *)"multipart/byteranges; boundary=_lws",
2418                                                  20, &p, end))
2419                         return -1;
2420
2421                 /*
2422                  *  our overall content length has to include
2423                  *
2424                  *  - (n + 1) x "_lws\r\n"
2425                  *  - n x Content-Type: xxx/xxx\r\n
2426                  *  - n x Content-Range: bytes xxx-yyy/zzz\r\n
2427                  *  - n x /r/n
2428                  *  - the actual payloads (aggregated in rp->agg)
2429                  *
2430                  *  Precompute it for the main response header
2431                  */
2432
2433                 computed_total_content_length = (unsigned long)rp->agg +
2434                                                 6 /* final _lws\r\n */;
2435
2436                 lws_ranges_reset(rp);
2437                 while (lws_ranges_next(rp)) {
2438                         n = lws_snprintf(cache_control, sizeof(cache_control),
2439                                         "bytes %llu-%llu/%llu",
2440                                         rp->start, rp->end, rp->extent);
2441
2442                         computed_total_content_length +=
2443                                         6 /* header _lws\r\n */ +
2444                                         14 + strlen(content_type) + 2 + /* Content-Type: xxx/xxx\r\n */
2445                                         15 + n + 2 + /* Content-Range: xxxx\r\n */
2446                                         2; /* /r/n */
2447                 }
2448
2449                 lws_ranges_reset(rp);
2450                 lws_ranges_next(rp);
2451         }
2452
2453         if (ranges == 1) {
2454                 computed_total_content_length = (unsigned long)rp->agg;
2455                 n = lws_snprintf(cache_control, sizeof(cache_control), "bytes %llu-%llu/%llu",
2456                                 rp->start, rp->end, rp->extent);
2457
2458                 if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_CONTENT_RANGE,
2459                                                  (unsigned char *)cache_control,
2460                                                  n, &p, end))
2461                         return -1;
2462         }
2463
2464         wsi->u.http.range.inside = 0;
2465
2466         if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_ACCEPT_RANGES,
2467                                          (unsigned char *)"bytes", 5, &p, end))
2468                 return -1;
2469 #endif
2470
2471         if (!wsi->sending_chunked) {
2472                 if (lws_add_http_header_content_length(wsi,
2473                                                        computed_total_content_length,
2474                                                        &p, end))
2475                         return -1;
2476         } else {
2477                 if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_TRANSFER_ENCODING,
2478                                                  (unsigned char *)"chunked",
2479                                                  7, &p, end))
2480                         return -1;
2481         }
2482
2483         if (wsi->cache_secs && wsi->cache_reuse) {
2484                 if (wsi->cache_revalidate) {
2485                         cc = cache_control;
2486                         cclen = sprintf(cache_control, "%s max-age: %u",
2487                                     intermediates[wsi->cache_intermediaries],
2488                                     wsi->cache_secs);
2489                 } else {
2490                         cc = "no-cache";
2491                         cclen = 8;
2492                 }
2493         }
2494
2495         if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_CACHE_CONTROL,
2496                         (unsigned char *)cc, cclen, &p, end))
2497                 return -1;
2498
2499         if (wsi->u.http.connection_type == HTTP_CONNECTION_KEEP_ALIVE)
2500                 if (lws_add_http_header_by_token(wsi, WSI_TOKEN_CONNECTION,
2501                                 (unsigned char *)"keep-alive", 10, &p, end))
2502                         return -1;
2503
2504         if (other_headers) {
2505                 if ((end - p) < other_headers_len)
2506                         return -1;
2507                 memcpy(p, other_headers, other_headers_len);
2508                 p += other_headers_len;
2509         }
2510
2511         if (lws_finalize_http_header(wsi, &p, end))
2512                 return -1;
2513
2514         ret = lws_write(wsi, response, p - response, LWS_WRITE_HTTP_HEADERS);
2515         if (ret != (p - response)) {
2516                 lwsl_err("_write returned %d from %ld\n", ret, (long)(p - response));
2517                 return -1;
2518         }
2519
2520         wsi->u.http.filepos = 0;
2521         wsi->state = LWSS_HTTP_ISSUING_FILE;
2522
2523         return lws_serve_http_file_fragment(wsi);
2524 }
2525
2526 int
2527 lws_interpret_incoming_packet(struct lws *wsi, unsigned char **buf, size_t len)
2528 {
2529         int m;
2530
2531         lwsl_parser("%s: received %d byte packet\n", __func__, (int)len);
2532 #if 0
2533         lwsl_hexdump(*buf, len);
2534 #endif
2535
2536         /* let the rx protocol state machine have as much as it needs */
2537
2538         while (len) {
2539                 /*
2540                  * we were accepting input but now we stopped doing so
2541                  */
2542                 if (!(wsi->rxflow_change_to & LWS_RXFLOW_ALLOW)) {
2543                         lws_rxflow_cache(wsi, *buf, 0, len);
2544                         lwsl_parser("%s: cached %ld\n", __func__, (long)len);
2545                         return 1;
2546                 }
2547
2548                 if (wsi->u.ws.rx_draining_ext) {
2549                         // lwsl_notice("draining with 0\n");
2550                         m = lws_rx_sm(wsi, 0);
2551                         if (m < 0)
2552                                 return -1;
2553                         continue;
2554                 }
2555
2556                 /* account for what we're using in rxflow buffer */
2557                 if (wsi->rxflow_buffer)
2558                         wsi->rxflow_pos++;
2559
2560                 /* consume payload bytes efficiently */
2561                 if (
2562                     wsi->lws_rx_parse_state ==
2563                     LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED) {
2564                         m = lws_payload_until_length_exhausted(wsi, buf, &len);
2565                         if (wsi->rxflow_buffer)
2566                                 wsi->rxflow_pos += m;
2567                 }
2568
2569                 /* process the byte */
2570                 m = lws_rx_sm(wsi, *(*buf)++);
2571                 if (m < 0)
2572                         return -1;
2573                 len--;
2574         }
2575
2576         lwsl_parser("%s: exit with %d unused\n", __func__, (int)len);
2577
2578         return 0;
2579 }
2580
2581 LWS_VISIBLE void
2582 lws_server_get_canonical_hostname(struct lws_context *context,
2583                                   struct lws_context_creation_info *info)
2584 {
2585         if (lws_check_opt(info->options, LWS_SERVER_OPTION_SKIP_SERVER_CANONICAL_NAME))
2586                 return;
2587 #if LWS_POSIX && !defined(LWS_WITH_ESP32)
2588         /* find canonical hostname */
2589         gethostname((char *)context->canonical_hostname,
2590                     sizeof(context->canonical_hostname) - 1);
2591
2592         lwsl_notice(" canonical_hostname = %s\n", context->canonical_hostname);
2593 #else
2594         (void)context;
2595 #endif
2596 }
2597
2598 #define LWS_MAX_ELEM_NAME 32
2599
2600 enum urldecode_stateful {
2601         US_NAME,
2602         US_IDLE,
2603         US_PC1,
2604         US_PC2,
2605
2606         MT_LOOK_BOUND_IN,
2607         MT_HNAME,
2608         MT_DISP,
2609         MT_TYPE,
2610         MT_IGNORE1,
2611         MT_IGNORE2,
2612 };
2613
2614 static const char * const mp_hdr[] = {
2615         "content-disposition: ",
2616         "content-type: ",
2617         "\x0d\x0a"
2618 };
2619
2620 typedef int (*lws_urldecode_stateful_cb)(void *data,
2621                 const char *name, char **buf, int len, int final);
2622
2623 struct lws_urldecode_stateful {
2624         char *out;
2625         void *data;
2626         char name[LWS_MAX_ELEM_NAME];
2627         char temp[LWS_MAX_ELEM_NAME];
2628         char content_type[32];
2629         char content_disp[32];
2630         char content_disp_filename[256];
2631         char mime_boundary[128];
2632         int out_len;
2633         int pos;
2634         int hdr_idx;
2635         int mp;
2636         int sum;
2637
2638         unsigned int multipart_form_data:1;
2639         unsigned int inside_quote:1;
2640         unsigned int subname:1;
2641         unsigned int boundary_real_crlf:1;
2642
2643         enum urldecode_stateful state;
2644
2645         lws_urldecode_stateful_cb output;
2646 };
2647
2648 static struct lws_urldecode_stateful *
2649 lws_urldecode_s_create(struct lws *wsi, char *out, int out_len, void *data,
2650                        lws_urldecode_stateful_cb output)
2651 {
2652         struct lws_urldecode_stateful *s = lws_zalloc(sizeof(*s));
2653         char buf[200], *p;
2654         int m = 0;
2655
2656         if (!s)
2657                 return NULL;
2658
2659         s->out = out;
2660         s->out_len  = out_len;
2661         s->output = output;
2662         s->pos = 0;
2663         s->sum = 0;
2664         s->mp = 0;
2665         s->state = US_NAME;
2666         s->name[0] = '\0';
2667         s->data = data;
2668
2669         if (lws_hdr_copy(wsi, buf, sizeof(buf), WSI_TOKEN_HTTP_CONTENT_TYPE) > 0) {
2670                 /* multipart/form-data; boundary=----WebKitFormBoundarycc7YgAPEIHvgE9Bf */
2671
2672                 if (!strncmp(buf, "multipart/form-data", 19)) {
2673                         s->multipart_form_data = 1;
2674                         s->state = MT_LOOK_BOUND_IN;
2675                         s->mp = 2;
2676                         p = strstr(buf, "boundary=");
2677                         if (p) {
2678                                 p += 9;
2679                                 s->mime_boundary[m++] = '\x0d';
2680                                 s->mime_boundary[m++] = '\x0a';
2681                                 s->mime_boundary[m++] = '-';
2682                                 s->mime_boundary[m++] = '-';
2683                                 while (m < sizeof(s->mime_boundary) - 1 &&
2684                                        *p && *p != ' ')
2685                                         s->mime_boundary[m++] = *p++;
2686
2687                                 s->mime_boundary[m] = '\0';
2688
2689                                 lwsl_notice("boundary '%s'\n", s->mime_boundary);
2690                         }
2691                 }
2692         }
2693
2694         return s;
2695 }
2696
2697 static int
2698 lws_urldecode_s_process(struct lws_urldecode_stateful *s, const char *in, int len)
2699 {
2700         int n, m, hit = 0;
2701         char c, was_end = 0;
2702
2703         while (len--) {
2704                 if (s->pos == s->out_len - s->mp - 1) {
2705                         if (s->output(s->data, s->name, &s->out, s->pos, 0))
2706                                 return -1;
2707
2708                         was_end = s->pos;
2709                         s->pos = 0;
2710                 }
2711                 switch (s->state) {
2712
2713                 /* states for url arg style */
2714
2715                 case US_NAME:
2716                         s->inside_quote = 0;
2717                         if (*in == '=') {
2718                                 s->name[s->pos] = '\0';
2719                                 s->pos = 0;
2720                                 s->state = US_IDLE;
2721                                 in++;
2722                                 continue;
2723                         }
2724                         if (*in == '&') {
2725                                 s->name[s->pos] = '\0';
2726                                 if (s->output(s->data, s->name, &s->out, s->pos, 1))
2727                                         return -1;
2728                                 s->pos = 0;
2729                                 s->state = US_IDLE;
2730                                 in++;
2731                                 continue;
2732                         }
2733                         if (s->pos >= sizeof(s->name) - 1) {
2734                                 lwsl_notice("Name too long\n");
2735                                 return -1;
2736                         }
2737                         s->name[s->pos++] = *in++;
2738                         break;
2739                 case US_IDLE:
2740                         if (*in == '%') {
2741                                 s->state++;
2742                                 in++;
2743                                 continue;
2744                         }
2745                         if (*in == '&') {
2746                                 s->out[s->pos] = '\0';
2747                                 if (s->output(s->data, s->name, &s->out, s->pos, 1))
2748                                         return -1;
2749                                 s->pos = 0;
2750                                 s->state = US_NAME;
2751                                 in++;
2752                                 continue;
2753                         }
2754                         if (*in == '+') {
2755                                 in++;
2756                                 s->out[s->pos++] = ' ';
2757                                 continue;
2758                         }
2759                         s->out[s->pos++] = *in++;
2760                         break;
2761                 case US_PC1:
2762                         n = char_to_hex(*in);
2763                         if (n < 0)
2764                                 return -1;
2765
2766                         in++;
2767                         s->sum = n << 4;
2768                         s->state++;
2769                         break;
2770
2771                 case US_PC2:
2772                         n = char_to_hex(*in);
2773                         if (n < 0)
2774                                 return -1;
2775
2776                         in++;
2777                         s->out[s->pos++] = s->sum | n;
2778                         s->state = US_IDLE;
2779                         break;
2780
2781
2782                 /* states for multipart / mime style */
2783
2784                 case MT_LOOK_BOUND_IN:
2785 retry_as_first:
2786                         if (*in == s->mime_boundary[s->mp] &&
2787                             s->mime_boundary[s->mp]) {
2788                                 in++;
2789                                 s->mp++;
2790                                 if (!s->mime_boundary[s->mp]) {
2791                                         s->mp = 0;
2792                                         s->state = MT_IGNORE1;
2793
2794                                         if (s->pos || was_end)
2795                                                 if (s->output(s->data, s->name,
2796                                                       &s->out, s->pos, 1))
2797                                                         return -1;
2798
2799                                         s->pos = 0;
2800
2801                                         s->content_disp[0] = '\0';
2802                                         s->name[0] = '\0';
2803                                         s->content_disp_filename[0] = '\0';
2804                                         s->boundary_real_crlf = 1;
2805                                 }
2806                                 continue;
2807                         }
2808                         if (s->mp) {
2809                                 n = 0;
2810                                 if (!s->boundary_real_crlf)
2811                                         n = 2;
2812
2813                                 memcpy(s->out + s->pos, s->mime_boundary + n, s->mp - n);
2814                                 s->pos += s->mp;
2815                                 s->mp = 0;
2816                                 goto retry_as_first;
2817                         }
2818
2819                         s->out[s->pos++] = *in;
2820                         in++;
2821                         s->mp = 0;
2822                         break;
2823
2824                 case MT_HNAME:
2825                         m = 0;
2826                         c =*in;
2827                         if (c >= 'A' && c <= 'Z')
2828                                 c += 'a' - 'A';
2829                         for (n = 0; n < ARRAY_SIZE(mp_hdr); n++)
2830                                 if (c == mp_hdr[n][s->mp]) {
2831                                         m++;
2832                                         hit = n;
2833                                 }
2834                         in++;
2835                         if (!m) {
2836                                 s->mp = 0;
2837                                 continue;
2838                         }
2839
2840                         s->mp++;
2841                         if (m != 1)
2842                                 continue;
2843
2844                         if (mp_hdr[hit][s->mp])
2845                                 continue;
2846
2847                         s->mp = 0;
2848                         s->temp[0] = '\0';
2849                         s->subname = 0;
2850
2851                         if (hit == 2)
2852                                 s->state = MT_LOOK_BOUND_IN;
2853                         else
2854                                 s->state += hit + 1;
2855                         break;
2856
2857                 case MT_DISP:
2858                         /* form-data; name="file"; filename="t.txt" */
2859
2860                         if (*in == '\x0d') {
2861 //                              lwsl_notice("disp: '%s', '%s', '%s'\n",
2862 //                                 s->content_disp, s->name,
2863 //                                 s->content_disp_filename);
2864
2865                                 if (s->content_disp_filename[0])
2866                                         if (s->output(s->data, s->name,
2867                                                       &s->out, s->pos, LWS_UFS_OPEN))
2868                                                 return -1;
2869                                 s->state = MT_IGNORE2;
2870                                 goto done;
2871                         }
2872                         if (*in == ';') {
2873                                 s->subname = 1;
2874                                 s->temp[0] = '\0';
2875                                 s->mp = 0;
2876                                 goto done;
2877                         }
2878
2879                         if (*in == '\"') {
2880                                 s->inside_quote ^= 1;
2881                                 goto done;
2882                         }
2883
2884                         if (s->subname) {
2885                                 if (*in == '=') {
2886                                         s->temp[s->mp] = '\0';
2887                                         s->subname = 0;
2888                                         s->mp = 0;
2889                                         goto done;
2890                                 }
2891                                 if (s->mp < sizeof(s->temp) - 1 &&
2892                                     (*in != ' ' || s->inside_quote))
2893                                         s->temp[s->mp++] = *in;
2894                                 goto done;
2895                         }
2896
2897                         if (!s->temp[0]) {
2898                                 if (s->mp < sizeof(s->content_disp) - 1)
2899                                         s->content_disp[s->mp++] = *in;
2900                                 s->content_disp[s->mp] = '\0';
2901                                 goto done;
2902                         }
2903
2904                         if (!strcmp(s->temp, "name")) {
2905                                 if (s->mp < sizeof(s->name) - 1)
2906                                         s->name[s->mp++] = *in;
2907                                 s->name[s->mp] = '\0';
2908                                 goto done;
2909                         }
2910
2911                         if (!strcmp(s->temp, "filename")) {
2912                                 if (s->mp < sizeof(s->content_disp_filename) - 1)
2913                                         s->content_disp_filename[s->mp++] = *in;
2914                                 s->content_disp_filename[s->mp] = '\0';
2915                                 goto done;
2916                         }
2917 done:
2918                         in++;
2919                         break;
2920
2921                 case MT_TYPE:
2922                         if (*in == '\x0d')
2923                                 s->state = MT_IGNORE2;
2924                         else {
2925                                 if (s->mp < sizeof(s->content_type) - 1)
2926                                         s->content_type[s->mp++] = *in;
2927                                 s->content_type[s->mp] = '\0';
2928                         }
2929                         in++;
2930                         break;
2931
2932                 case MT_IGNORE1:
2933                         if (*in == '\x0d')
2934                                 s->state = MT_IGNORE2;
2935                         in++;
2936                         break;
2937
2938                 case MT_IGNORE2:
2939                         s->mp = 0;
2940                         if (*in == '\x0a')
2941                                 s->state = MT_HNAME;
2942                         in++;
2943                         break;
2944                 }
2945         }
2946
2947         return 0;
2948 }
2949
2950 static int
2951 lws_urldecode_s_destroy(struct lws_urldecode_stateful *s)
2952 {
2953         int ret = 0;
2954
2955         if (s->state != US_IDLE)
2956                 ret = -1;
2957
2958         if (!ret)
2959                 if (s->output(s->data, s->name, &s->out, s->pos, 1))
2960                         ret = -1;
2961
2962         lws_free(s);
2963
2964         return ret;
2965 }
2966
2967 struct lws_spa {
2968         struct lws_urldecode_stateful *s;
2969         lws_spa_fileupload_cb opt_cb;
2970         const char * const *param_names;
2971         int count_params;
2972         char **params;
2973         int *param_length;
2974         void *opt_data;
2975
2976         char *storage;
2977         char *end;
2978         int max_storage;
2979
2980         char finalized;
2981 };
2982
2983 static int
2984 lws_urldecode_spa_lookup(struct lws_spa *spa,
2985                          const char *name)
2986 {
2987         int n;
2988
2989         for (n = 0; n < spa->count_params; n++)
2990                 if (!strcmp(spa->param_names[n], name))
2991                         return n;
2992
2993         return -1;
2994 }
2995
2996 static int
2997 lws_urldecode_spa_cb(void *data, const char *name, char **buf, int len,
2998                      int final)
2999 {
3000         struct lws_spa *spa =
3001                         (struct lws_spa *)data;
3002         int n;
3003
3004         if (spa->s->content_disp_filename[0]) {
3005                 if (spa->opt_cb) {
3006                         n = spa->opt_cb(spa->opt_data, name,
3007                                         spa->s->content_disp_filename,
3008                                         *buf, len, final);
3009
3010                         if (n < 0)
3011                                 return -1;
3012                 }
3013                 return 0;
3014         }
3015         n = lws_urldecode_spa_lookup(spa, name);
3016
3017         if (n == -1 || !len) /* unrecognized */
3018                 return 0;
3019
3020         if (!spa->params[n])
3021                 spa->params[n] = *buf;
3022
3023         if ((*buf) + len >= spa->end) {
3024                 lwsl_notice("%s: exceeded storage\n", __func__);
3025                 return -1;
3026         }
3027
3028         spa->param_length[n] += len;
3029
3030         /* move it on inside storage */
3031         (*buf) += len;
3032         *((*buf)++) = '\0';
3033
3034         spa->s->out_len -= len + 1;
3035
3036         return 0;
3037 }
3038
3039 LWS_VISIBLE LWS_EXTERN struct lws_spa *
3040 lws_spa_create(struct lws *wsi, const char * const *param_names,
3041                          int count_params, int max_storage,
3042                          lws_spa_fileupload_cb opt_cb, void *opt_data)
3043 {
3044         struct lws_spa *spa = lws_zalloc(sizeof(*spa));
3045
3046         if (!spa)
3047                 return NULL;
3048
3049         spa->param_names = param_names;
3050         spa->count_params = count_params;
3051         spa->max_storage = max_storage;
3052         spa->opt_cb = opt_cb;
3053         spa->opt_data = opt_data;
3054
3055         spa->storage = lws_malloc(max_storage);
3056         if (!spa->storage)
3057                 goto bail2;
3058         spa->end = spa->storage + max_storage - 1;
3059
3060         spa->params = lws_zalloc(sizeof(char *) * count_params);
3061         if (!spa->params)
3062                 goto bail3;
3063
3064         spa->s = lws_urldecode_s_create(wsi, spa->storage, max_storage, spa,
3065                                         lws_urldecode_spa_cb);
3066         if (!spa->s)
3067                 goto bail4;
3068
3069         spa->param_length = lws_zalloc(sizeof(int) * count_params);
3070         if (!spa->param_length)
3071                 goto bail5;
3072
3073         lwsl_info("%s: Created SPA %p\n", __func__, spa);
3074
3075         return spa;
3076
3077 bail5:
3078         lws_urldecode_s_destroy(spa->s);
3079 bail4:
3080         lws_free(spa->params);
3081 bail3:
3082         lws_free(spa->storage);
3083 bail2:
3084         lws_free(spa);
3085
3086         return NULL;
3087 }
3088
3089 LWS_VISIBLE LWS_EXTERN int
3090 lws_spa_process(struct lws_spa *ludspa, const char *in, int len)
3091 {
3092         if (!ludspa) {
3093                 lwsl_err("%s: NULL spa\n", __func__);
3094                 return -1;
3095         }
3096         /* we reject any junk after the last part arrived and we finalized */
3097         if (ludspa->finalized)
3098                 return 0;
3099
3100         return lws_urldecode_s_process(ludspa->s, in, len);
3101 }
3102
3103 LWS_VISIBLE LWS_EXTERN int
3104 lws_spa_get_length(struct lws_spa *ludspa, int n)
3105 {
3106         if (n >= ludspa->count_params)
3107                 return 0;
3108
3109         return ludspa->param_length[n];
3110 }
3111
3112 LWS_VISIBLE LWS_EXTERN const char *
3113 lws_spa_get_string(struct lws_spa *ludspa, int n)
3114 {
3115         if (n >= ludspa->count_params)
3116                 return NULL;
3117
3118         return ludspa->params[n];
3119 }
3120
3121 LWS_VISIBLE LWS_EXTERN int
3122 lws_spa_finalize(struct lws_spa *spa)
3123 {
3124         if (spa->s) {
3125                 lws_urldecode_s_destroy(spa->s);
3126                 spa->s = NULL;
3127         }
3128
3129         spa->finalized = 1;
3130
3131         return 0;
3132 }
3133
3134 LWS_VISIBLE LWS_EXTERN int
3135 lws_spa_destroy(struct lws_spa *spa)
3136 {
3137         int n = 0;
3138
3139         lwsl_notice("%s: destroy spa %p\n", __func__, spa);
3140
3141         if (spa->s)
3142                 lws_urldecode_s_destroy(spa->s);
3143
3144         lwsl_debug("%s %p %p %p %p\n", __func__,
3145                         spa->param_length,
3146                         spa->params,
3147                         spa->storage,
3148                         spa
3149                         );
3150
3151         lws_free(spa->param_length);
3152         lws_free(spa->params);
3153         lws_free(spa->storage);
3154         lws_free(spa);
3155
3156         return n;
3157 }
3158
3159 #if 0
3160 LWS_VISIBLE LWS_EXTERN int
3161 lws_spa_destroy(struct lws_spa *spa)
3162 {
3163         int n = 0;
3164
3165         lwsl_info("%s: destroy spa %p\n", __func__, spa);
3166
3167         if (spa->s)
3168                 lws_urldecode_s_destroy(spa->s);
3169
3170         lwsl_debug("%s\n", __func__);
3171
3172         lws_free(spa->param_length);
3173         lws_free(spa->params);
3174         lws_free(spa->storage);
3175         lws_free(spa);
3176
3177         return n;
3178 }
3179 #endif
3180 LWS_VISIBLE LWS_EXTERN int
3181 lws_chunked_html_process(struct lws_process_html_args *args,
3182                          struct lws_process_html_state *s)
3183 {
3184         char *sp, buffer[32];
3185         const char *pc;
3186         int old_len, n;
3187
3188         /* do replacements */
3189         sp = args->p;
3190         old_len = args->len;
3191         args->len = 0;
3192         s->start = sp;
3193         while (sp < args->p + old_len) {
3194
3195                 if (args->len + 7 >= args->max_len) {
3196                         lwsl_err("Used up interpret padding\n");
3197                         return -1;
3198                 }
3199
3200                 if ((!s->pos && *sp == '$') || s->pos) {
3201                         int hits = 0, hit = 0;
3202
3203                         if (!s->pos)
3204                                 s->start = sp;
3205                         s->swallow[s->pos++] = *sp;
3206                         if (s->pos == sizeof(s->swallow) - 1)
3207                                 goto skip;
3208                         for (n = 0; n < s->count_vars; n++)
3209                                 if (!strncmp(s->swallow, s->vars[n], s->pos)) {
3210                                         hits++;
3211                                         hit = n;
3212                                 }
3213                         if (!hits) {
3214 skip:
3215                                 s->swallow[s->pos] = '\0';
3216                                 memcpy(s->start, s->swallow, s->pos);
3217                                 args->len++;
3218                                 s->pos = 0;
3219                                 sp = s->start + 1;
3220                                 continue;
3221                         }
3222                         if (hits == 1 && s->pos == strlen(s->vars[hit])) {
3223                                 pc = s->replace(s->data, hit);
3224                                 if (!pc)
3225                                         pc = "NULL";
3226                                 n = strlen(pc);
3227                                 s->swallow[s->pos] = '\0';
3228                                 if (n != s->pos) {
3229                                         memmove(s->start + n,
3230                                                 s->start + s->pos,
3231                                                 old_len - (sp - args->p));
3232                                         old_len += (n - s->pos) + 1;
3233                                 }
3234                                 memcpy(s->start, pc, n);
3235                                 args->len++;
3236                                 sp = s->start + 1;
3237
3238                                 s->pos = 0;
3239                         }
3240                         sp++;
3241                         continue;
3242                 }
3243
3244                 args->len++;
3245                 sp++;
3246         }
3247
3248         /* no space left for final chunk trailer */
3249         if (args->final && args->len + 7 >= args->max_len)
3250                 return -1;
3251
3252         n = sprintf(buffer, "%X\x0d\x0a", args->len);
3253
3254         args->p -= n;
3255         memcpy(args->p, buffer, n);
3256         args->len += n;
3257
3258         if (args->final) {
3259                 sp = args->p + args->len;
3260                 *sp++ = '\x0d';
3261                 *sp++ = '\x0a';
3262                 *sp++ = '0';
3263                 *sp++ = '\x0d';
3264                 *sp++ = '\x0a';
3265                 *sp++ = '\x0d';
3266                 *sp++ = '\x0a';
3267                 args->len += 7;
3268         } else {
3269                 sp = args->p + args->len;
3270                 *sp++ = '\x0d';
3271                 *sp++ = '\x0a';
3272                 args->len += 2;
3273         }
3274
3275         return 0;
3276 }