| 1 | /* |
| 2 | ashd - A Sane HTTP Daemon |
| 3 | Copyright (C) 2008 Fredrik Tolf <fredrik@dolda2000.com> |
| 4 | |
| 5 | This program is free software: you can redistribute it and/or modify |
| 6 | it under the terms of the GNU General Public License as published by |
| 7 | the Free Software Foundation, either version 3 of the License, or |
| 8 | (at your option) any later version. |
| 9 | |
| 10 | This program is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | GNU General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU General Public License |
| 16 | along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 17 | */ |
| 18 | |
| 19 | #include <stdlib.h> |
| 20 | #include <unistd.h> |
| 21 | #include <stdio.h> |
| 22 | #include <fcntl.h> |
| 23 | #include <string.h> |
| 24 | #include <sys/socket.h> |
| 25 | #include <pwd.h> |
| 26 | #include <sys/signal.h> |
| 27 | #include <errno.h> |
| 28 | |
| 29 | #ifdef HAVE_CONFIG_H |
| 30 | #include <config.h> |
| 31 | #endif |
| 32 | #include <utils.h> |
| 33 | #include <mt.h> |
| 34 | #include <mtio.h> |
| 35 | #include <log.h> |
| 36 | #include <req.h> |
| 37 | #include <proc.h> |
| 38 | |
| 39 | #include "htparser.h" |
| 40 | |
| 41 | static int plex; |
| 42 | static char *pidfile = NULL; |
| 43 | static int daemonize, usesyslog; |
| 44 | struct mtbuf listeners; |
| 45 | |
| 46 | static void trimx(struct hthead *req) |
| 47 | { |
| 48 | int i; |
| 49 | |
| 50 | i = 0; |
| 51 | while(i < req->noheaders) { |
| 52 | if(!strncasecmp(req->headers[i][0], "x-ash-", 6)) { |
| 53 | free(req->headers[i][0]); |
| 54 | free(req->headers[i][1]); |
| 55 | free(req->headers[i]); |
| 56 | memmove(req->headers + i, req->headers + i + 1, sizeof(*req->headers) * (--req->noheaders - i)); |
| 57 | } else { |
| 58 | i++; |
| 59 | } |
| 60 | } |
| 61 | } |
| 62 | |
| 63 | static struct hthead *parsereq(FILE *in) |
| 64 | { |
| 65 | struct hthead *req; |
| 66 | struct charbuf method, url, ver; |
| 67 | int c; |
| 68 | |
| 69 | req = NULL; |
| 70 | bufinit(method); |
| 71 | bufinit(url); |
| 72 | bufinit(ver); |
| 73 | while(1) { |
| 74 | c = getc(in); |
| 75 | if(c == ' ') { |
| 76 | break; |
| 77 | } else if((c == EOF) || (c < 32) || (c >= 128)) { |
| 78 | goto fail; |
| 79 | } else { |
| 80 | bufadd(method, c); |
| 81 | if(method.d >= 128) |
| 82 | goto fail; |
| 83 | } |
| 84 | } |
| 85 | while(1) { |
| 86 | c = getc(in); |
| 87 | if(c == ' ') { |
| 88 | break; |
| 89 | } else if((c == EOF) || (c < 32)) { |
| 90 | goto fail; |
| 91 | } else { |
| 92 | bufadd(url, c); |
| 93 | if(url.d >= 65536) |
| 94 | goto fail; |
| 95 | } |
| 96 | } |
| 97 | while(1) { |
| 98 | c = getc(in); |
| 99 | if(c == 10) { |
| 100 | break; |
| 101 | } else if(c == 13) { |
| 102 | } else if((c == EOF) || (c < 32) || (c >= 128)) { |
| 103 | goto fail; |
| 104 | } else { |
| 105 | bufadd(ver, c); |
| 106 | if(ver.d >= 128) |
| 107 | goto fail; |
| 108 | } |
| 109 | } |
| 110 | bufadd(method, 0); |
| 111 | bufadd(url, 0); |
| 112 | bufadd(ver, 0); |
| 113 | req = mkreq(method.b, url.b, ver.b); |
| 114 | if(parseheaders(req, in)) |
| 115 | goto fail; |
| 116 | trimx(req); |
| 117 | goto out; |
| 118 | |
| 119 | fail: |
| 120 | if(req != NULL) { |
| 121 | freehthead(req); |
| 122 | req = NULL; |
| 123 | } |
| 124 | out: |
| 125 | buffree(method); |
| 126 | buffree(url); |
| 127 | buffree(ver); |
| 128 | return(req); |
| 129 | } |
| 130 | |
| 131 | static off_t passdata(FILE *in, FILE *out, off_t max) |
| 132 | { |
| 133 | size_t read; |
| 134 | off_t total; |
| 135 | char buf[8192]; |
| 136 | |
| 137 | total = 0; |
| 138 | while(!feof(in) && ((max < 0) || (total < max))) { |
| 139 | read = sizeof(buf); |
| 140 | if(max >= 0) |
| 141 | read = min(max - total, read); |
| 142 | read = fread(buf, 1, read, in); |
| 143 | if(ferror(in)) |
| 144 | return(-1); |
| 145 | if(fwrite(buf, 1, read, out) != read) |
| 146 | return(-1); |
| 147 | total += read; |
| 148 | } |
| 149 | return(total); |
| 150 | } |
| 151 | |
| 152 | static int recvchunks(FILE *in, FILE *out) |
| 153 | { |
| 154 | char buf[8192]; |
| 155 | size_t read, chlen; |
| 156 | int c, r; |
| 157 | |
| 158 | while(1) { |
| 159 | chlen = 0; |
| 160 | r = 0; |
| 161 | while(1) { |
| 162 | c = getc(in); |
| 163 | if(c == 10) { |
| 164 | if(!r) |
| 165 | return(-1); |
| 166 | break; |
| 167 | } else if(c == 13) { |
| 168 | } else if((c >= '0') && (c <= '9')) { |
| 169 | chlen = (chlen << 4) + (c - '0'); |
| 170 | r = 1; |
| 171 | } else if((c >= 'A') && (c <= 'F')) { |
| 172 | chlen = (chlen << 4) + (c + 10 - 'A'); |
| 173 | r = 1; |
| 174 | } else if((c >= 'a') && (c <= 'f')) { |
| 175 | chlen = (chlen << 4) + (c + 10 - 'a'); |
| 176 | r = 1; |
| 177 | } else { |
| 178 | /* XXX: Technically, there may be chunk extensions to |
| 179 | * be read, but since that will likely never actually |
| 180 | * happen in practice, I can just as well add support |
| 181 | * for that if it actually does become relevant. */ |
| 182 | return(-1); |
| 183 | } |
| 184 | } |
| 185 | if(chlen == 0) |
| 186 | break; |
| 187 | while(chlen > 0) { |
| 188 | read = fread(buf, 1, min(sizeof(buf), chlen), in); |
| 189 | if(feof(in) || ferror(in)) |
| 190 | return(-1); |
| 191 | if(fwrite(buf, 1, read, out) != read) |
| 192 | return(-1); |
| 193 | chlen -= read; |
| 194 | } |
| 195 | if((getc(in) != 13) || (getc(in) != 10)) |
| 196 | return(-1); |
| 197 | } |
| 198 | /* XXX: Technically, there may be trailers to be read, but that's |
| 199 | * just about as likely as chunk extensions. */ |
| 200 | if((getc(in) != 13) || (getc(in) != 10)) |
| 201 | return(-1); |
| 202 | return(0); |
| 203 | } |
| 204 | |
| 205 | static int passchunks(FILE *in, FILE *out) |
| 206 | { |
| 207 | char buf[8192]; |
| 208 | size_t read; |
| 209 | |
| 210 | do { |
| 211 | read = fread(buf, 1, sizeof(buf), in); |
| 212 | if(ferror(in)) |
| 213 | return(-1); |
| 214 | fprintf(out, "%zx\r\n", read); |
| 215 | if(fwrite(buf, 1, read, out) != read) |
| 216 | return(-1); |
| 217 | fprintf(out, "\r\n"); |
| 218 | } while(read > 0); |
| 219 | return(0); |
| 220 | } |
| 221 | |
| 222 | static int hasheader(struct hthead *head, char *name, char *val) |
| 223 | { |
| 224 | char *hd; |
| 225 | |
| 226 | if((hd = getheader(head, name)) == NULL) |
| 227 | return(0); |
| 228 | return(!strcasecmp(hd, val)); |
| 229 | } |
| 230 | |
| 231 | static int canonreq(struct hthead *req) |
| 232 | { |
| 233 | char *p, *p2, *r; |
| 234 | int n; |
| 235 | |
| 236 | if(req->url[0] == '/') { |
| 237 | replrest(req, req->url + 1); |
| 238 | if((p = strchr(req->rest, '?')) != NULL) |
| 239 | *p = 0; |
| 240 | return(1); |
| 241 | } |
| 242 | if((p = strstr(req->url, "://")) != NULL) { |
| 243 | n = p - req->url; |
| 244 | if(((n == 4) && !strncasecmp(req->url, "http", 4)) || |
| 245 | ((n == 5) && !strncasecmp(req->url, "https", 5))) { |
| 246 | if(getheader(req, "host")) |
| 247 | return(0); |
| 248 | p += 3; |
| 249 | if((p2 = strchr(p, '/')) == NULL) { |
| 250 | headappheader(req, "Host", p); |
| 251 | free(req->url); |
| 252 | req->url = sstrdup("/"); |
| 253 | } else { |
| 254 | r = sstrdup(p2); |
| 255 | *(p2++) = 0; |
| 256 | headappheader(req, "Host", p); |
| 257 | free(req->url); |
| 258 | req->url = r; |
| 259 | } |
| 260 | replrest(req, req->url + 1); |
| 261 | if((p = strchr(req->rest, '?')) != NULL) |
| 262 | *p = 0; |
| 263 | return(1); |
| 264 | } |
| 265 | } |
| 266 | return(0); |
| 267 | } |
| 268 | |
| 269 | static int http10keep(struct hthead *req, struct hthead *resp) |
| 270 | { |
| 271 | int fc; |
| 272 | |
| 273 | fc = hasheader(resp, "connection", "close"); |
| 274 | headrmheader(resp, "connection"); |
| 275 | if(!fc && hasheader(req, "connection", "keep-alive")) { |
| 276 | headappheader(resp, "Connection", "Keep-Alive"); |
| 277 | return(1); |
| 278 | } else { |
| 279 | return(0); |
| 280 | } |
| 281 | } |
| 282 | |
| 283 | void serve(FILE *in, struct conn *conn) |
| 284 | { |
| 285 | int pfds[2]; |
| 286 | FILE *out; |
| 287 | struct hthead *req, *resp; |
| 288 | char *hd; |
| 289 | off_t dlen; |
| 290 | int keep; |
| 291 | |
| 292 | out = NULL; |
| 293 | req = resp = NULL; |
| 294 | while(plex >= 0) { |
| 295 | if((req = parsereq(in)) == NULL) |
| 296 | break; |
| 297 | if(!canonreq(req)) |
| 298 | break; |
| 299 | |
| 300 | if((conn->initreq != NULL) && conn->initreq(conn, req)) |
| 301 | break; |
| 302 | |
| 303 | if((plex < 0) || block(plex, EV_WRITE, 60) <= 0) |
| 304 | break; |
| 305 | if(socketpair(PF_UNIX, SOCK_STREAM, 0, pfds)) |
| 306 | break; |
| 307 | if(sendreq(plex, req, pfds[0])) |
| 308 | break; |
| 309 | close(pfds[0]); |
| 310 | out = mtstdopen(pfds[1], 1, 600, "r+"); |
| 311 | |
| 312 | if(getheader(req, "content-type") != NULL) { |
| 313 | if((hd = getheader(req, "content-length")) != NULL) { |
| 314 | dlen = atoo(hd); |
| 315 | if(dlen > 0) { |
| 316 | if(passdata(in, out, dlen) != dlen) |
| 317 | break; |
| 318 | } |
| 319 | } else if(((hd = getheader(req, "transfer-encoding")) != NULL) && !strcasecmp(hd, "chunked")) { |
| 320 | if(recvchunks(in, out)) |
| 321 | break; |
| 322 | } else { |
| 323 | /* Ignore rather than abort, to be kinder to broken clients. */ |
| 324 | headrmheader(req, "content-type"); |
| 325 | } |
| 326 | } |
| 327 | if(fflush(out)) |
| 328 | break; |
| 329 | /* Make sure to send EOF */ |
| 330 | shutdown(pfds[1], SHUT_WR); |
| 331 | |
| 332 | if((resp = parseresponse(out)) == NULL) |
| 333 | break; |
| 334 | replstr(&resp->ver, req->ver); |
| 335 | |
| 336 | if(!getheader(resp, "server")) |
| 337 | headappheader(resp, "Server", sprintf3("ashd/%s", VERSION)); |
| 338 | |
| 339 | if(!strcasecmp(req->ver, "HTTP/1.0")) { |
| 340 | if(!strcasecmp(req->method, "head")) { |
| 341 | keep = http10keep(req, resp); |
| 342 | writeresp(in, resp); |
| 343 | fprintf(in, "\r\n"); |
| 344 | } else if((hd = getheader(resp, "content-length")) != NULL) { |
| 345 | keep = http10keep(req, resp); |
| 346 | dlen = atoo(hd); |
| 347 | writeresp(in, resp); |
| 348 | fprintf(in, "\r\n"); |
| 349 | if(passdata(out, in, dlen) != dlen) |
| 350 | break; |
| 351 | } else { |
| 352 | headrmheader(resp, "connection"); |
| 353 | writeresp(in, resp); |
| 354 | fprintf(in, "\r\n"); |
| 355 | passdata(out, in, -1); |
| 356 | break; |
| 357 | } |
| 358 | if(!keep) |
| 359 | break; |
| 360 | } else if(!strcasecmp(req->ver, "HTTP/1.1")) { |
| 361 | if(!strcasecmp(req->method, "head")) { |
| 362 | writeresp(in, resp); |
| 363 | fprintf(in, "\r\n"); |
| 364 | } else if((hd = getheader(resp, "content-length")) != NULL) { |
| 365 | writeresp(in, resp); |
| 366 | fprintf(in, "\r\n"); |
| 367 | dlen = atoo(hd); |
| 368 | if(passdata(out, in, dlen) != dlen) |
| 369 | break; |
| 370 | } else if(!getheader(resp, "transfer-encoding")) { |
| 371 | headappheader(resp, "Transfer-Encoding", "chunked"); |
| 372 | writeresp(in, resp); |
| 373 | fprintf(in, "\r\n"); |
| 374 | if(passchunks(out, in)) |
| 375 | break; |
| 376 | } else { |
| 377 | writeresp(in, resp); |
| 378 | fprintf(in, "\r\n"); |
| 379 | passdata(out, in, -1); |
| 380 | break; |
| 381 | } |
| 382 | if(hasheader(req, "connection", "close") || hasheader(resp, "connection", "close")) |
| 383 | break; |
| 384 | } else { |
| 385 | break; |
| 386 | } |
| 387 | |
| 388 | fclose(out); |
| 389 | out = NULL; |
| 390 | freehthead(req); |
| 391 | freehthead(resp); |
| 392 | req = resp = NULL; |
| 393 | } |
| 394 | |
| 395 | if(out != NULL) |
| 396 | fclose(out); |
| 397 | if(req != NULL) |
| 398 | freehthead(req); |
| 399 | if(resp != NULL) |
| 400 | freehthead(resp); |
| 401 | fclose(in); |
| 402 | } |
| 403 | |
| 404 | static void plexwatch(struct muth *muth, va_list args) |
| 405 | { |
| 406 | vavar(int, fd); |
| 407 | char *buf; |
| 408 | int i, s, ret; |
| 409 | |
| 410 | s = 0; |
| 411 | while(1) { |
| 412 | if(block(fd, EV_READ, 0) == 0) |
| 413 | break; |
| 414 | buf = smalloc(65536); |
| 415 | ret = recv(fd, buf, 65536, 0); |
| 416 | if(ret < 0) { |
| 417 | flog(LOG_WARNING, "received error on rootplex read channel: %s", strerror(errno)); |
| 418 | exit(1); |
| 419 | } else if(ret == 0) { |
| 420 | s = 1; |
| 421 | free(buf); |
| 422 | break; |
| 423 | } |
| 424 | /* Maybe I'd like to implement some protocol in this direction |
| 425 | * some day... */ |
| 426 | free(buf); |
| 427 | } |
| 428 | shutdown(plex, SHUT_RDWR); |
| 429 | for(i = 0; i < listeners.d; i++) { |
| 430 | if(listeners.b[i] == muth) |
| 431 | bufdel(listeners, i); |
| 432 | } |
| 433 | if(s) { |
| 434 | flog(LOG_INFO, "root handler exited, so shutting down listening..."); |
| 435 | while(listeners.d > 0) |
| 436 | resume(listeners.b[0], 0); |
| 437 | } |
| 438 | } |
| 439 | |
| 440 | static void initroot(void *uu) |
| 441 | { |
| 442 | int fd; |
| 443 | |
| 444 | setsid(); |
| 445 | if(daemonize) { |
| 446 | chdir("/"); |
| 447 | if((fd = open("/dev/null", O_RDWR)) >= 0) { |
| 448 | dup2(fd, 0); |
| 449 | dup2(fd, 1); |
| 450 | dup2(fd, 2); |
| 451 | close(fd); |
| 452 | } |
| 453 | } |
| 454 | if(usesyslog) |
| 455 | putenv("ASHD_USESYSLOG=1"); |
| 456 | else |
| 457 | unsetenv("ASHD_USESYSLOG"); |
| 458 | } |
| 459 | |
| 460 | static void usage(FILE *out) |
| 461 | { |
| 462 | fprintf(out, "usage: htparser [-hSf] [-u USER] [-r ROOT] [-p PIDFILE] PORTSPEC... -- ROOT [ARGS...]\n"); |
| 463 | fprintf(out, "\twhere PORTSPEC is HANDLER[:PAR[=VAL][(,PAR[=VAL])...]] (try HANDLER:help)\n"); |
| 464 | fprintf(out, "\tavailable handlers are `plain' and `ssl'.\n"); |
| 465 | } |
| 466 | |
| 467 | static void addport(char *spec) |
| 468 | { |
| 469 | char *nm, *p, *p2, *n; |
| 470 | struct charvbuf pars, vals; |
| 471 | |
| 472 | bufinit(pars); |
| 473 | bufinit(vals); |
| 474 | if((p = strchr(spec, ':')) == NULL) { |
| 475 | nm = spec; |
| 476 | } else { |
| 477 | nm = spec; |
| 478 | *(p++) = 0; |
| 479 | do { |
| 480 | if((n = strchr(p, ',')) != NULL) |
| 481 | *(n++) = 0; |
| 482 | if((p2 = strchr(p, '=')) != NULL) |
| 483 | *(p2++) = 0; |
| 484 | if(!*p) { |
| 485 | usage(stderr); |
| 486 | exit(1); |
| 487 | } |
| 488 | bufadd(pars, p); |
| 489 | if(p2) |
| 490 | bufadd(vals, p2); |
| 491 | else |
| 492 | bufadd(vals, ""); |
| 493 | } while((p = n) != NULL); |
| 494 | } |
| 495 | |
| 496 | /* XXX: It would be nice to decentralize this, but, meh... */ |
| 497 | if(!strcmp(nm, "plain")) { |
| 498 | handleplain(pars.d, pars.b, vals.b); |
| 499 | #ifdef HAVE_GNUTLS |
| 500 | } else if(!strcmp(nm, "ssl")) { |
| 501 | handlegnussl(pars.d, pars.b, vals.b); |
| 502 | #endif |
| 503 | } else { |
| 504 | flog(LOG_ERR, "htparser: unknown port handler `%s'", nm); |
| 505 | exit(1); |
| 506 | } |
| 507 | |
| 508 | buffree(pars); |
| 509 | buffree(vals); |
| 510 | } |
| 511 | |
| 512 | static void sighandler(int sig) |
| 513 | { |
| 514 | exitioloop(1); |
| 515 | } |
| 516 | |
| 517 | int main(int argc, char **argv) |
| 518 | { |
| 519 | int c, d; |
| 520 | int i, s1; |
| 521 | char *root; |
| 522 | FILE *pidout; |
| 523 | struct passwd *pwent; |
| 524 | |
| 525 | daemonize = usesyslog = 0; |
| 526 | root = NULL; |
| 527 | pwent = NULL; |
| 528 | while((c = getopt(argc, argv, "+hSfu:r:p:")) >= 0) { |
| 529 | switch(c) { |
| 530 | case 'h': |
| 531 | usage(stdout); |
| 532 | exit(0); |
| 533 | case 'f': |
| 534 | daemonize = 1; |
| 535 | break; |
| 536 | case 'S': |
| 537 | usesyslog = 1; |
| 538 | break; |
| 539 | case 'u': |
| 540 | if((pwent = getpwnam(optarg)) == NULL) { |
| 541 | flog(LOG_ERR, "could not find user %s", optarg); |
| 542 | exit(1); |
| 543 | } |
| 544 | break; |
| 545 | case 'r': |
| 546 | root = optarg; |
| 547 | break; |
| 548 | case 'p': |
| 549 | pidfile = optarg; |
| 550 | break; |
| 551 | default: |
| 552 | usage(stderr); |
| 553 | exit(1); |
| 554 | } |
| 555 | } |
| 556 | s1 = 0; |
| 557 | for(i = optind; i < argc; i++) { |
| 558 | if(!strcmp(argv[i], "--")) |
| 559 | break; |
| 560 | s1 = 1; |
| 561 | addport(argv[i]); |
| 562 | } |
| 563 | if(!s1 || (i == argc)) { |
| 564 | usage(stderr); |
| 565 | exit(1); |
| 566 | } |
| 567 | if((plex = stdmkchild(argv + ++i, initroot, NULL)) < 0) { |
| 568 | flog(LOG_ERR, "could not spawn root multiplexer: %s", strerror(errno)); |
| 569 | return(1); |
| 570 | } |
| 571 | bufadd(listeners, mustart(plexwatch, plex)); |
| 572 | pidout = NULL; |
| 573 | if(pidfile != NULL) { |
| 574 | if((pidout = fopen(pidfile, "w")) == NULL) { |
| 575 | flog(LOG_ERR, "could not open %s for writing: %s", pidfile, strerror(errno)); |
| 576 | return(1); |
| 577 | } |
| 578 | } |
| 579 | if(usesyslog) |
| 580 | opensyslog(); |
| 581 | if(root) { |
| 582 | if(chdir(root) || chroot(root)) { |
| 583 | flog(LOG_ERR, "could not chroot to %s: %s", root, strerror(errno)); |
| 584 | exit(1); |
| 585 | } |
| 586 | } |
| 587 | if(pwent) { |
| 588 | if(setgid(pwent->pw_gid)) { |
| 589 | flog(LOG_ERR, "could not switch group to %i: %s", (int)pwent->pw_gid, strerror(errno)); |
| 590 | exit(1); |
| 591 | } |
| 592 | if(setuid(pwent->pw_uid)) { |
| 593 | flog(LOG_ERR, "could not switch user to %i: %s", (int)pwent->pw_uid, strerror(errno)); |
| 594 | exit(1); |
| 595 | } |
| 596 | } |
| 597 | signal(SIGPIPE, SIG_IGN); |
| 598 | signal(SIGCHLD, SIG_IGN); |
| 599 | signal(SIGINT, sighandler); |
| 600 | signal(SIGTERM, sighandler); |
| 601 | if(daemonize) { |
| 602 | daemon(0, 0); |
| 603 | } |
| 604 | if(pidout != NULL) { |
| 605 | fprintf(pidout, "%i\n", getpid()); |
| 606 | fclose(pidout); |
| 607 | } |
| 608 | d = 0; |
| 609 | while(!d) { |
| 610 | switch(ioloop()) { |
| 611 | case 0: |
| 612 | d = 1; |
| 613 | break; |
| 614 | case 1: |
| 615 | if(listeners.d > 0) { |
| 616 | while(listeners.d > 0) |
| 617 | resume(listeners.b[0], 0); |
| 618 | flog(LOG_INFO, "no longer listening"); |
| 619 | } else { |
| 620 | d = 1; |
| 621 | } |
| 622 | break; |
| 623 | } |
| 624 | } |
| 625 | return(0); |
| 626 | } |