1 /*- 2 * Copyright (c) 2000-2004 Dag-Erling Co�dan Sm�rgrav 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer 10 * in this position and unchanged. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. The name of the author may not be used to endorse or promote products 15 * derived from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 /* 33 * The following copyright applies to the base64 code: 34 * 35 *- 36 * Copyright 1997 Massachusetts Institute of Technology 37 * 38 * Permission to use, copy, modify, and distribute this software and 39 * its documentation for any purpose and without fee is hereby 40 * granted, provided that both the above copyright notice and this 41 * permission notice appear in all copies, that both the above 42 * copyright notice and this permission notice appear in all 43 * supporting documentation, and that the name of M.I.T. not be used 44 * in advertising or publicity pertaining to distribution of the 45 * software without specific, written prior permission. M.I.T. makes 46 * no representations about the suitability of this software for any 47 * purpose. It is provided "as is" without express or implied 48 * warranty. 49 * 50 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS 51 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE, 52 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 53 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT 54 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 55 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 56 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 57 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 58 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 59 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 60 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 61 * SUCH DAMAGE. 62 */ 63 64 #include <sys/param.h> 65 #include <sys/socket.h> 66 67 #include <ctype.h> 68 #include <err.h> 69 #include <errno.h> 70 #include <locale.h> 71 #include <netdb.h> 72 #include <stdarg.h> 73 #include <stdio.h> 74 #include <stdlib.h> 75 #include <string.h> 76 #include <time.h> 77 #include <unistd.h> 78 79 #include <netinet/in.h> 80 #include <netinet/tcp.h> 81 82 #include "fetch.h" 83 #include "common.h" 84 #include "httperr.h" 85 86 /* Maximum number of redirects to follow */ 87 #define MAX_REDIRECT 5 88 89 /* Symbolic names for reply codes we care about */ 90 #define HTTP_OK 200 91 #define HTTP_PARTIAL 206 92 #define HTTP_MOVED_PERM 301 93 #define HTTP_MOVED_TEMP 302 94 #define HTTP_SEE_OTHER 303 95 #define HTTP_NEED_AUTH 401 96 #define HTTP_NEED_PROXY_AUTH 407 97 #define HTTP_BAD_RANGE 416 98 #define HTTP_PROTOCOL_ERROR 999 99 100 #define HTTP_REDIRECT(xyz) ((xyz) == HTTP_MOVED_PERM \ 101 || (xyz) == HTTP_MOVED_TEMP \ 102 || (xyz) == HTTP_SEE_OTHER) 103 104 #define HTTP_ERROR(xyz) ((xyz) > 400 && (xyz) < 599) 105 106 107 /***************************************************************************** 108 * I/O functions for decoding chunked streams 109 */ 110 111 struct httpio 112 { 113 conn_t *conn; /* connection */ 114 int chunked; /* chunked mode */ 115 char *buf; /* chunk buffer */ 116 size_t bufsize; /* size of chunk buffer */ 117 ssize_t buflen; /* amount of data currently in buffer */ 118 int bufpos; /* current read offset in buffer */ 119 int eof; /* end-of-file flag */ 120 int error; /* error flag */ 121 size_t chunksize; /* remaining size of current chunk */ 122 #ifndef NDEBUG 123 size_t total; 124 #endif 125 }; 126 127 /* 128 * Get next chunk header 129 */ 130 static int 131 _http_new_chunk(struct httpio *io) 132 { 133 char *p; 134 135 if (_fetch_getln(io->conn) == -1) 136 return (-1); 137 138 if (io->conn->buflen < 2 || !ishexnumber(*io->conn->buf)) 139 return (-1); 140 141 for (p = io->conn->buf; *p && !isspace(*p); ++p) { 142 if (*p == ';') 143 break; 144 if (!ishexnumber(*p)) 145 return (-1); 146 if (isdigit(*p)) { 147 io->chunksize = io->chunksize * 16 + 148 *p - '0'; 149 } else { 150 io->chunksize = io->chunksize * 16 + 151 10 + tolower(*p) - 'a'; 152 } 153 } 154 155 #ifndef NDEBUG 156 if (fetchDebug) { 157 io->total += io->chunksize; 158 if (io->chunksize == 0) 159 fprintf(stderr, "%s(): end of last chunk\n", __func__); 160 else 161 fprintf(stderr, "%s(): new chunk: %lu (%lu)\n", 162 __func__, (unsigned long)io->chunksize, 163 (unsigned long)io->total); 164 } 165 #endif 166 167 return (io->chunksize); 168 } 169 170 /* 171 * Grow the input buffer to at least len bytes 172 */ 173 static inline int 174 _http_growbuf(struct httpio *io, size_t len) 175 { 176 char *tmp; 177 178 if (io->bufsize >= len) 179 return (0); 180 181 if ((tmp = realloc(io->buf, len)) == NULL) 182 return (-1); 183 io->buf = tmp; 184 io->bufsize = len; 185 return (0); 186 } 187 188 /* 189 * Fill the input buffer, do chunk decoding on the fly 190 */ 191 static int 192 _http_fillbuf(struct httpio *io, size_t len) 193 { 194 if (io->error) 195 return (-1); 196 if (io->eof) 197 return (0); 198 199 if (io->chunked == 0) { 200 if (_http_growbuf(io, len) == -1) 201 return (-1); 202 if ((io->buflen = _fetch_read(io->conn, io->buf, len)) == -1) { 203 io->error = 1; 204 return (-1); 205 } 206 io->bufpos = 0; 207 return (io->buflen); 208 } 209 210 if (io->chunksize == 0) { 211 switch (_http_new_chunk(io)) { 212 case -1: 213 io->error = 1; 214 return (-1); 215 case 0: 216 io->eof = 1; 217 return (0); 218 } 219 } 220 221 if (len > io->chunksize) 222 len = io->chunksize; 223 if (_http_growbuf(io, len) == -1) 224 return (-1); 225 if ((io->buflen = _fetch_read(io->conn, io->buf, len)) == -1) { 226 io->error = 1; 227 return (-1); 228 } 229 io->chunksize -= io->buflen; 230 231 if (io->chunksize == 0) { 232 char endl[2]; 233 234 if (_fetch_read(io->conn, endl, 2) != 2 || 235 endl[0] != '\r' || endl[1] != '\n') 236 return (-1); 237 } 238 239 io->bufpos = 0; 240 241 return (io->buflen); 242 } 243 244 /* 245 * Read function 246 */ 247 static int 248 _http_readfn(void *v, char *buf, int len) 249 { 250 struct httpio *io = (struct httpio *)v; 251 int l, pos; 252 253 if (io->error) 254 return (-1); 255 if (io->eof) 256 return (0); 257 258 for (pos = 0; len > 0; pos += l, len -= l) { 259 /* empty buffer */ 260 if (!io->buf || io->bufpos == io->buflen) 261 if (_http_fillbuf(io, len) < 1) 262 break; 263 l = io->buflen - io->bufpos; 264 if (len < l) 265 l = len; 266 bcopy(io->buf + io->bufpos, buf + pos, l); 267 io->bufpos += l; 268 } 269 270 if (!pos && io->error) 271 return (-1); 272 return (pos); 273 } 274 275 /* 276 * Write function 277 */ 278 static int 279 _http_writefn(void *v, const char *buf, int len) 280 { 281 struct httpio *io = (struct httpio *)v; 282 283 return (_fetch_write(io->conn, buf, len)); 284 } 285 286 /* 287 * Close function 288 */ 289 static int 290 _http_closefn(void *v) 291 { 292 struct httpio *io = (struct httpio *)v; 293 int r; 294 295 r = _fetch_close(io->conn); 296 if (io->buf) 297 free(io->buf); 298 free(io); 299 return (r); 300 } 301 302 /* 303 * Wrap a file descriptor up 304 */ 305 static FILE * 306 _http_funopen(conn_t *conn, int chunked) 307 { 308 struct httpio *io; 309 FILE *f; 310 311 if ((io = calloc(1, sizeof(*io))) == NULL) { 312 _fetch_syserr(); 313 return (NULL); 314 } 315 io->conn = conn; 316 io->chunked = chunked; 317 f = funopen(io, _http_readfn, _http_writefn, NULL, _http_closefn); 318 if (f == NULL) { 319 _fetch_syserr(); 320 free(io); 321 return (NULL); 322 } 323 return (f); 324 } 325 326 327 /***************************************************************************** 328 * Helper functions for talking to the server and parsing its replies 329 */ 330 331 /* Header types */ 332 typedef enum { 333 hdr_syserror = -2, 334 hdr_error = -1, 335 hdr_end = 0, 336 hdr_unknown = 1, 337 hdr_content_length, 338 hdr_content_range, 339 hdr_last_modified, 340 hdr_location, 341 hdr_transfer_encoding, 342 hdr_www_authenticate 343 } hdr_t; 344 345 /* Names of interesting headers */ 346 static struct { 347 hdr_t num; 348 const char *name; 349 } hdr_names[] = { 350 { hdr_content_length, "Content-Length" }, 351 { hdr_content_range, "Content-Range" }, 352 { hdr_last_modified, "Last-Modified" }, 353 { hdr_location, "Location" }, 354 { hdr_transfer_encoding, "Transfer-Encoding" }, 355 { hdr_www_authenticate, "WWW-Authenticate" }, 356 { hdr_unknown, NULL }, 357 }; 358 359 /* 360 * Send a formatted line; optionally echo to terminal 361 */ 362 static int 363 _http_cmd(conn_t *conn, const char *fmt, ...) 364 { 365 va_list ap; 366 size_t len; 367 char *msg; 368 int r; 369 370 va_start(ap, fmt); 371 len = vasprintf(&msg, fmt, ap); 372 va_end(ap); 373 374 if (msg == NULL) { 375 errno = ENOMEM; 376 _fetch_syserr(); 377 return (-1); 378 } 379 380 r = _fetch_putln(conn, msg, len); 381 free(msg); 382 383 if (r == -1) { 384 _fetch_syserr(); 385 return (-1); 386 } 387 388 return (0); 389 } 390 391 /* 392 * Get and parse status line 393 */ 394 static int 395 _http_get_reply(conn_t *conn) 396 { 397 char *p; 398 399 if (_fetch_getln(conn) == -1) 400 return (-1); 401 /* 402 * A valid status line looks like "HTTP/m.n xyz reason" where m 403 * and n are the major and minor protocol version numbers and xyz 404 * is the reply code. 405 * Unfortunately, there are servers out there (NCSA 1.5.1, to name 406 * just one) that do not send a version number, so we can't rely 407 * on finding one, but if we do, insist on it being 1.0 or 1.1. 408 * We don't care about the reason phrase. 409 */ 410 if (strncmp(conn->buf, "HTTP", 4) != 0) 411 return (HTTP_PROTOCOL_ERROR); 412 p = conn->buf + 4; 413 if (*p == '/') { 414 if (p[1] != '1' || p[2] != '.' || (p[3] != '0' && p[3] != '1')) 415 return (HTTP_PROTOCOL_ERROR); 416 p += 4; 417 } 418 if (*p != ' ' || !isdigit(p[1]) || !isdigit(p[2]) || !isdigit(p[3])) 419 return (HTTP_PROTOCOL_ERROR); 420 421 conn->err = (p[1] - '0') * 100 + (p[2] - '0') * 10 + (p[3] - '0'); 422 return (conn->err); 423 } 424 425 /* 426 * Check a header; if the type matches the given string, return a pointer 427 * to the beginning of the value. 428 */ 429 static const char * 430 _http_match(const char *str, const char *hdr) 431 { 432 while (*str && *hdr && tolower(*str++) == tolower(*hdr++)) 433 /* nothing */; 434 if (*str || *hdr != ':') 435 return (NULL); 436 while (*hdr && isspace(*++hdr)) 437 /* nothing */; 438 return (hdr); 439 } 440 441 /* 442 * Get the next header and return the appropriate symbolic code. 443 */ 444 static hdr_t 445 _http_next_header(conn_t *conn, const char **p) 446 { 447 int i; 448 449 if (_fetch_getln(conn) == -1) 450 return (hdr_syserror); 451 while (conn->buflen && isspace(conn->buf[conn->buflen - 1])) 452 conn->buflen--; 453 conn->buf[conn->buflen] = '\0'; 454 if (conn->buflen == 0) 455 return (hdr_end); 456 /* 457 * We could check for malformed headers but we don't really care. 458 * A valid header starts with a token immediately followed by a 459 * colon; a token is any sequence of non-control, non-whitespace 460 * characters except "()<>@,;:\\\"{}". 461 */ 462 for (i = 0; hdr_names[i].num != hdr_unknown; i++) 463 if ((*p = _http_match(hdr_names[i].name, conn->buf)) != NULL) 464 return (hdr_names[i].num); 465 return (hdr_unknown); 466 } 467 468 /* 469 * Parse a last-modified header 470 */ 471 static int 472 _http_parse_mtime(const char *p, time_t *mtime) 473 { 474 char locale[64], *r; 475 struct tm tm; 476 477 strncpy(locale, setlocale(LC_TIME, NULL), sizeof(locale)); 478 setlocale(LC_TIME, "C"); 479 r = strptime(p, "%a, %d %b %Y %H:%M:%S GMT", &tm); 480 /* XXX should add support for date-2 and date-3 */ 481 setlocale(LC_TIME, locale); 482 if (r == NULL) 483 return (-1); 484 DEBUG(fprintf(stderr, "last modified: [%04d-%02d-%02d " 485 "%02d:%02d:%02d]\n", 486 tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, 487 tm.tm_hour, tm.tm_min, tm.tm_sec)); 488 *mtime = timegm(&tm); 489 return (0); 490 } 491 492 /* 493 * Parse a content-length header 494 */ 495 static int 496 _http_parse_length(const char *p, off_t *length) 497 { 498 off_t len; 499 500 for (len = 0; *p && isdigit(*p); ++p) 501 len = len * 10 + (*p - '0'); 502 if (*p) 503 return (-1); 504 DEBUG(fprintf(stderr, "content length: [%lld]\n", 505 (long long)len)); 506 *length = len; 507 return (0); 508 } 509 510 /* 511 * Parse a content-range header 512 */ 513 static int 514 _http_parse_range(const char *p, off_t *offset, off_t *length, off_t *size) 515 { 516 off_t first, last, len; 517 518 if (strncasecmp(p, "bytes ", 6) != 0) 519 return (-1); 520 p += 6; 521 if (*p == '*') { 522 first = last = -1; 523 ++p; 524 } else { 525 for (first = 0; *p && isdigit(*p); ++p) 526 first = first * 10 + *p - '0'; 527 if (*p != '-') 528 return (-1); 529 for (last = 0, ++p; *p && isdigit(*p); ++p) 530 last = last * 10 + *p - '0'; 531 } 532 if (first > last || *p != '/') 533 return (-1); 534 for (len = 0, ++p; *p && isdigit(*p); ++p) 535 len = len * 10 + *p - '0'; 536 if (*p || len < last - first + 1) 537 return (-1); 538 if (first == -1) { 539 DEBUG(fprintf(stderr, "content range: [*/%lld]\n", 540 (long long)len)); 541 *length = 0; 542 } else { 543 DEBUG(fprintf(stderr, "content range: [%lld-%lld/%lld]\n", 544 (long long)first, (long long)last, (long long)len)); 545 *length = last - first + 1; 546 } 547 *offset = first; 548 *size = len; 549 return (0); 550 } 551 552 553 /***************************************************************************** 554 * Helper functions for authorization 555 */ 556 557 /* 558 * Base64 encoding 559 */ 560 static char * 561 _http_base64(const char *src) 562 { 563 static const char base64[] = 564 "ABCDEFGHIJKLMNOPQRSTUVWXYZ" 565 "abcdefghijklmnopqrstuvwxyz" 566 "0123456789+/"; 567 char *str, *dst; 568 size_t l; 569 int t, r; 570 571 l = strlen(src); 572 if ((str = malloc(((l + 2) / 3) * 4 + 1)) == NULL) 573 return (NULL); 574 dst = str; 575 r = 0; 576 577 while (l >= 3) { 578 t = (src[0] << 16) | (src[1] << 8) | src[2]; 579 dst[0] = base64[(t >> 18) & 0x3f]; 580 dst[1] = base64[(t >> 12) & 0x3f]; 581 dst[2] = base64[(t >> 6) & 0x3f]; 582 dst[3] = base64[(t >> 0) & 0x3f]; 583 src += 3; l -= 3; 584 dst += 4; r += 4; 585 } 586 587 switch (l) { 588 case 2: 589 t = (src[0] << 16) | (src[1] << 8); 590 dst[0] = base64[(t >> 18) & 0x3f]; 591 dst[1] = base64[(t >> 12) & 0x3f]; 592 dst[2] = base64[(t >> 6) & 0x3f]; 593 dst[3] = '='; 594 dst += 4; 595 r += 4; 596 break; 597 case 1: 598 t = src[0] << 16; 599 dst[0] = base64[(t >> 18) & 0x3f]; 600 dst[1] = base64[(t >> 12) & 0x3f]; 601 dst[2] = dst[3] = '='; 602 dst += 4; 603 r += 4; 604 break; 605 case 0: 606 break; 607 } 608 609 *dst = 0; 610 return (str); 611 } 612 613 /* 614 * Encode username and password 615 */ 616 static int 617 _http_basic_auth(conn_t *conn, const char *hdr, const char *usr, const char *pwd) 618 { 619 char *upw, *auth; 620 int r; 621 622 DEBUG(fprintf(stderr, "usr: [%s]\n", usr)); 623 DEBUG(fprintf(stderr, "pwd: [%s]\n", pwd)); 624 if (asprintf(&upw, "%s:%s", usr, pwd) == -1) 625 return (-1); 626 auth = _http_base64(upw); 627 free(upw); 628 if (auth == NULL) 629 return (-1); 630 r = _http_cmd(conn, "%s: Basic %s", hdr, auth); 631 free(auth); 632 return (r); 633 } 634 635 /* 636 * Send an authorization header 637 */ 638 static int 639 _http_authorize(conn_t *conn, const char *hdr, const char *p) 640 { 641 /* basic authorization */ 642 if (strncasecmp(p, "basic:", 6) == 0) { 643 char *user, *pwd, *str; 644 int r; 645 646 /* skip realm */ 647 for (p += 6; *p && *p != ':'; ++p) 648 /* nothing */ ; 649 if (!*p || strchr(++p, ':') == NULL) 650 return (-1); 651 if ((str = strdup(p)) == NULL) 652 return (-1); /* XXX */ 653 user = str; 654 pwd = strchr(str, ':'); 655 *pwd++ = '\0'; 656 r = _http_basic_auth(conn, hdr, user, pwd); 657 free(str); 658 return (r); 659 } 660 return (-1); 661 } 662 663 664 /***************************************************************************** 665 * Helper functions for connecting to a server or proxy 666 */ 667 668 /* 669 * Connect to the correct HTTP server or proxy. 670 */ 671 static conn_t * 672 _http_connect(struct url *URL, struct url *purl, const char *flags) 673 { 674 conn_t *conn; 675 int verbose; 676 int af, val; 677 678 #ifdef INET6 679 af = AF_UNSPEC; 680 #else 681 af = AF_INET; 682 #endif 683 684 verbose = CHECK_FLAG('v'); 685 if (CHECK_FLAG('4')) 686 af = AF_INET; 687 #ifdef INET6 688 else if (CHECK_FLAG('6')) 689 af = AF_INET6; 690 #endif 691 692 if (purl && strcasecmp(URL->scheme, SCHEME_HTTPS) != 0) { 693 URL = purl; 694 } else if (strcasecmp(URL->scheme, SCHEME_FTP) == 0) { 695 /* can't talk http to an ftp server */ 696 /* XXX should set an error code */ 697 return (NULL); 698 } 699 700 if ((conn = _fetch_connect(URL->host, URL->port, af, verbose)) == NULL) 701 /* _fetch_connect() has already set an error code */ 702 return (NULL); 703 if (strcasecmp(URL->scheme, SCHEME_HTTPS) == 0 && 704 _fetch_ssl(conn, verbose) == -1) { 705 _fetch_close(conn); 706 /* grrr */ 707 errno = EAUTH; 708 _fetch_syserr(); 709 return (NULL); 710 } 711 712 val = 1; 713 setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, sizeof(val)); 714 715 return (conn); 716 } 717 718 static struct url * 719 _http_get_proxy(const char *flags) 720 { 721 struct url *purl; 722 char *p; 723 724 if (flags != NULL && strchr(flags, 'd') != NULL) 725 return (NULL); 726 if (((p = getenv("HTTP_PROXY")) || (p = getenv("http_proxy"))) && 727 *p && (purl = fetchParseURL(p))) { 728 if (!*purl->scheme) 729 strcpy(purl->scheme, SCHEME_HTTP); 730 if (!purl->port) 731 purl->port = _fetch_default_proxy_port(purl->scheme); 732 if (strcasecmp(purl->scheme, SCHEME_HTTP) == 0) 733 return (purl); 734 fetchFreeURL(purl); 735 } 736 return (NULL); 737 } 738 739 static void 740 _http_print_html(FILE *out, FILE *in) 741 { 742 size_t len; 743 char *line, *p, *q; 744 int comment, tag; 745 746 comment = tag = 0; 747 while ((line = fgetln(in, &len)) != NULL) { 748 while (len && isspace(line[len - 1])) 749 --len; 750 for (p = q = line; q < line + len; ++q) { 751 if (comment && *q == '-') { 752 if (q + 2 < line + len && 753 strcmp(q, "-->") == 0) { 754 tag = comment = 0; 755 q += 2; 756 } 757 } else if (tag && !comment && *q == '>') { 758 p = q + 1; 759 tag = 0; 760 } else if (!tag && *q == '<') { 761 if (q > p) 762 fwrite(p, q - p, 1, out); 763 tag = 1; 764 if (q + 3 < line + len && 765 strcmp(q, "<!--") == 0) { 766 comment = 1; 767 q += 3; 768 } 769 } 770 } 771 if (!tag && q > p) 772 fwrite(p, q - p, 1, out); 773 fputc('\n', out); 774 } 775 } 776 777 778 /***************************************************************************** 779 * Core 780 */ 781 782 /* 783 * Send a request and process the reply 784 * 785 * XXX This function is way too long, the do..while loop should be split 786 * XXX off into a separate function. 787 */ 788 FILE * 789 _http_request(struct url *URL, const char *op, struct url_stat *us, 790 struct url *purl, const char *flags) 791 { 792 conn_t *conn; 793 struct url *url, *new; 794 int chunked, direct, need_auth, noredirect, verbose; 795 int e, i, n, val; 796 off_t offset, clength, length, size; 797 time_t mtime; 798 const char *p; 799 FILE *f; 800 hdr_t h; 801 char hbuf[MAXHOSTNAMELEN + 7], *host; 802 803 direct = CHECK_FLAG('d'); 804 noredirect = CHECK_FLAG('A'); 805 verbose = CHECK_FLAG('v'); 806 807 if (direct && purl) { 808 fetchFreeURL(purl); 809 purl = NULL; 810 } 811 812 /* try the provided URL first */ 813 url = URL; 814 815 /* if the A flag is set, we only get one try */ 816 n = noredirect ? 1 : MAX_REDIRECT; 817 i = 0; 818 819 e = HTTP_PROTOCOL_ERROR; 820 need_auth = 0; 821 do { 822 new = NULL; 823 chunked = 0; 824 offset = 0; 825 clength = -1; 826 length = -1; 827 size = -1; 828 mtime = 0; 829 830 /* check port */ 831 if (!url->port) 832 url->port = _fetch_default_port(url->scheme); 833 834 /* were we redirected to an FTP URL? */ 835 if (purl == NULL && strcmp(url->scheme, SCHEME_FTP) == 0) { 836 if (strcmp(op, "GET") == 0) 837 return (_ftp_request(url, "RETR", us, purl, flags)); 838 else if (strcmp(op, "HEAD") == 0) 839 return (_ftp_request(url, "STAT", us, purl, flags)); 840 } 841 842 /* connect to server or proxy */ 843 if ((conn = _http_connect(url, purl, flags)) == NULL) 844 goto ouch; 845 846 host = url->host; 847 #ifdef INET6 848 if (strchr(url->host, ':')) { 849 snprintf(hbuf, sizeof(hbuf), "[%s]", url->host); 850 host = hbuf; 851 } 852 #endif 853 if (url->port != _fetch_default_port(url->scheme)) { 854 if (host != hbuf) { 855 strcpy(hbuf, host); 856 host = hbuf; 857 } 858 snprintf(hbuf + strlen(hbuf), 859 sizeof(hbuf) - strlen(hbuf), ":%d", url->port); 860 } 861 862 /* send request */ 863 if (verbose) 864 _fetch_info("requesting %s://%s%s", 865 url->scheme, host, url->doc); 866 if (purl) { 867 _http_cmd(conn, "%s %s://%s%s HTTP/1.1", 868 op, url->scheme, host, url->doc); 869 } else { 870 _http_cmd(conn, "%s %s HTTP/1.1", 871 op, url->doc); 872 } 873 874 /* virtual host */ 875 _http_cmd(conn, "Host: %s", host); 876 877 /* proxy authorization */ 878 if (purl) { 879 if (*purl->user || *purl->pwd) 880 _http_basic_auth(conn, "Proxy-Authorization", 881 purl->user, purl->pwd); 882 else if ((p = getenv("HTTP_PROXY_AUTH")) != NULL && *p != '\0') 883 _http_authorize(conn, "Proxy-Authorization", p); 884 } 885 886 /* server authorization */ 887 if (need_auth || *url->user || *url->pwd) { 888 if (*url->user || *url->pwd) 889 _http_basic_auth(conn, "Authorization", url->user, url->pwd); 890 else if ((p = getenv("HTTP_AUTH")) != NULL && *p != '\0') 891 _http_authorize(conn, "Authorization", p); 892 else if (fetchAuthMethod && fetchAuthMethod(url) == 0) { 893 _http_basic_auth(conn, "Authorization", url->user, url->pwd); 894 } else { 895 _http_seterr(HTTP_NEED_AUTH); 896 goto ouch; 897 } 898 } 899 900 /* other headers */ 901 if ((p = getenv("HTTP_REFERER")) != NULL && *p != '\0') { 902 if (strcasecmp(p, "auto") == 0) 903 _http_cmd(conn, "Referer: %s://%s%s", 904 url->scheme, host, url->doc); 905 else 906 _http_cmd(conn, "Referer: %s", p); 907 } 908 if ((p = getenv("HTTP_USER_AGENT")) != NULL && *p != '\0') 909 _http_cmd(conn, "User-Agent: %s", p); 910 else 911 _http_cmd(conn, "User-Agent: %s " _LIBFETCH_VER, getprogname()); 912 if (url->offset > 0) 913 _http_cmd(conn, "Range: bytes=%lld-", (long long)url->offset); 914 _http_cmd(conn, "Connection: close"); 915 _http_cmd(conn, ""); 916 917 /* 918 * Force the queued request to be dispatched. Normally, one 919 * would do this with shutdown(2) but squid proxies can be 920 * configured to disallow such half-closed connections. To 921 * be compatible with such configurations, fiddle with socket 922 * options to force the pending data to be written. 923 */ 924 val = 0; 925 setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, 926 sizeof(val)); 927 val = 1; 928 setsockopt(conn->sd, IPPROTO_TCP, TCP_NODELAY, &val, 929 sizeof(val)); 930 931 /* get reply */ 932 switch (_http_get_reply(conn)) { 933 case HTTP_OK: 934 case HTTP_PARTIAL: 935 /* fine */ 936 break; 937 case HTTP_MOVED_PERM: 938 case HTTP_MOVED_TEMP: 939 case HTTP_SEE_OTHER: 940 /* 941 * Not so fine, but we still have to read the 942 * headers to get the new location. 943 */ 944 break; 945 case HTTP_NEED_AUTH: 946 if (need_auth) { 947 /* 948 * We already sent out authorization code, 949 * so there's nothing more we can do. 950 */ 951 _http_seterr(conn->err); 952 goto ouch; 953 } 954 /* try again, but send the password this time */ 955 if (verbose) 956 _fetch_info("server requires authorization"); 957 break; 958 case HTTP_NEED_PROXY_AUTH: 959 /* 960 * If we're talking to a proxy, we already sent 961 * our proxy authorization code, so there's 962 * nothing more we can do. 963 */ 964 _http_seterr(conn->err); 965 goto ouch; 966 case HTTP_BAD_RANGE: 967 /* 968 * This can happen if we ask for 0 bytes because 969 * we already have the whole file. Consider this 970 * a success for now, and check sizes later. 971 */ 972 break; 973 case HTTP_PROTOCOL_ERROR: 974 /* fall through */ 975 case -1: 976 _fetch_syserr(); 977 goto ouch; 978 default: 979 _http_seterr(conn->err); 980 if (!verbose) 981 goto ouch; 982 /* fall through so we can get the full error message */ 983 } 984 985 /* get headers */ 986 do { 987 switch ((h = _http_next_header(conn, &p))) { 988 case hdr_syserror: 989 _fetch_syserr(); 990 goto ouch; 991 case hdr_error: 992 _http_seterr(HTTP_PROTOCOL_ERROR); 993 goto ouch; 994 case hdr_content_length: 995 _http_parse_length(p, &clength); 996 break; 997 case hdr_content_range: 998 _http_parse_range(p, &offset, &length, &size); 999 break; 1000 case hdr_last_modified: 1001 _http_parse_mtime(p, &mtime); 1002 break; 1003 case hdr_location: 1004 if (!HTTP_REDIRECT(conn->err)) 1005 break; 1006 if (new) 1007 free(new); 1008 if (verbose) 1009 _fetch_info("%d redirect to %s", conn->err, p); 1010 if (*p == '/') 1011 /* absolute path */ 1012 new = fetchMakeURL(url->scheme, url->host, url->port, p, 1013 url->user, url->pwd); 1014 else 1015 new = fetchParseURL(p); 1016 if (new == NULL) { 1017 /* XXX should set an error code */ 1018 DEBUG(fprintf(stderr, "failed to parse new URL\n")); 1019 goto ouch; 1020 } 1021 if (!*new->user && !*new->pwd) { 1022 strcpy(new->user, url->user); 1023 strcpy(new->pwd, url->pwd); 1024 } 1025 new->offset = url->offset; 1026 new->length = url->length; 1027 break; 1028 case hdr_transfer_encoding: 1029 /* XXX weak test*/ 1030 chunked = (strcasecmp(p, "chunked") == 0); 1031 break; 1032 case hdr_www_authenticate: 1033 if (conn->err != HTTP_NEED_AUTH) 1034 break; 1035 /* if we were smarter, we'd check the method and realm */ 1036 break; 1037 case hdr_end: 1038 /* fall through */ 1039 case hdr_unknown: 1040 /* ignore */ 1041 break; 1042 } 1043 } while (h > hdr_end); 1044 1045 /* we need to provide authentication */ 1046 if (conn->err == HTTP_NEED_AUTH) { 1047 e = conn->err; 1048 need_auth = 1; 1049 _fetch_close(conn); 1050 conn = NULL; 1051 continue; 1052 } 1053 1054 /* requested range not satisfiable */ 1055 if (conn->err == HTTP_BAD_RANGE) { 1056 if (url->offset == size && url->length == 0) { 1057 /* asked for 0 bytes; fake it */ 1058 offset = url->offset; 1059 conn->err = HTTP_OK; 1060 break; 1061 } else { 1062 _http_seterr(conn->err); 1063 goto ouch; 1064 } 1065 } 1066 1067 /* we have a hit or an error */ 1068 if (conn->err == HTTP_OK || conn->err == HTTP_PARTIAL || HTTP_ERROR(conn->err)) 1069 break; 1070 1071 /* all other cases: we got a redirect */ 1072 e = conn->err; 1073 need_auth = 0; 1074 _fetch_close(conn); 1075 conn = NULL; 1076 if (!new) { 1077 DEBUG(fprintf(stderr, "redirect with no new location\n")); 1078 break; 1079 } 1080 if (url != URL) 1081 fetchFreeURL(url); 1082 url = new; 1083 } while (++i < n); 1084 1085 /* we failed, or ran out of retries */ 1086 if (conn == NULL) { 1087 _http_seterr(e); 1088 goto ouch; 1089 } 1090 1091 DEBUG(fprintf(stderr, "offset %lld, length %lld," 1092 " size %lld, clength %lld\n", 1093 (long long)offset, (long long)length, 1094 (long long)size, (long long)clength)); 1095 1096 /* check for inconsistencies */ 1097 if (clength != -1 && length != -1 && clength != length) { 1098 _http_seterr(HTTP_PROTOCOL_ERROR); 1099 goto ouch; 1100 } 1101 if (clength == -1) 1102 clength = length; 1103 if (clength != -1) 1104 length = offset + clength; 1105 if (length != -1 && size != -1 && length != size) { 1106 _http_seterr(HTTP_PROTOCOL_ERROR); 1107 goto ouch; 1108 } 1109 if (size == -1) 1110 size = length; 1111 1112 /* fill in stats */ 1113 if (us) { 1114 us->size = size; 1115 us->atime = us->mtime = mtime; 1116 } 1117 1118 /* too far? */ 1119 if (URL->offset > 0 && offset > URL->offset) { 1120 _http_seterr(HTTP_PROTOCOL_ERROR); 1121 goto ouch; 1122 } 1123 1124 /* report back real offset and size */ 1125 URL->offset = offset; 1126 URL->length = clength; 1127 1128 /* wrap it up in a FILE */ 1129 if ((f = _http_funopen(conn, chunked)) == NULL) { 1130 _fetch_syserr(); 1131 goto ouch; 1132 } 1133 1134 if (url != URL) 1135 fetchFreeURL(url); 1136 if (purl) 1137 fetchFreeURL(purl); 1138 1139 if (HTTP_ERROR(conn->err)) { 1140 _http_print_html(stderr, f); 1141 fclose(f); 1142 f = NULL; 1143 } 1144 1145 return (f); 1146 1147 ouch: 1148 if (url != URL) 1149 fetchFreeURL(url); 1150 if (purl) 1151 fetchFreeURL(purl); 1152 if (conn != NULL) 1153 _fetch_close(conn); 1154 return (NULL); 1155 } 1156 1157 1158 /***************************************************************************** 1159 * Entry points 1160 */ 1161 1162 /* 1163 * Retrieve and stat a file by HTTP 1164 */ 1165 FILE * 1166 fetchXGetHTTP(struct url *URL, struct url_stat *us, const char *flags) 1167 { 1168 return (_http_request(URL, "GET", us, _http_get_proxy(flags), flags)); 1169 } 1170 1171 /* 1172 * Retrieve a file by HTTP 1173 */ 1174 FILE * 1175 fetchGetHTTP(struct url *URL, const char *flags) 1176 { 1177 return (fetchXGetHTTP(URL, NULL, flags)); 1178 } 1179 1180 /* 1181 * Store a file by HTTP 1182 */ 1183 FILE * 1184 fetchPutHTTP(struct url *URL __unused, const char *flags __unused) 1185 { 1186 warnx("fetchPutHTTP(): not implemented"); 1187 return (NULL); 1188 } 1189 1190 /* 1191 * Get an HTTP document's metadata 1192 */ 1193 int 1194 fetchStatHTTP(struct url *URL, struct url_stat *us, const char *flags) 1195 { 1196 FILE *f; 1197 1198 f = _http_request(URL, "HEAD", us, _http_get_proxy(flags), flags); 1199 if (f == NULL) 1200 return (-1); 1201 fclose(f); 1202 return (0); 1203 } 1204 1205 /* 1206 * List a directory 1207 */ 1208 struct url_ent * 1209 fetchListHTTP(struct url *url __unused, const char *flags __unused) 1210 { 1211 warnx("fetchListHTTP(): not implemented"); 1212 return (NULL); 1213 } 1214