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_TEMP_REDIRECT 307 96 #define HTTP_NEED_AUTH 401 97 #define HTTP_NEED_PROXY_AUTH 407 98 #define HTTP_BAD_RANGE 416 99 #define HTTP_PROTOCOL_ERROR 999 100 101 #define HTTP_REDIRECT(xyz) ((xyz) == HTTP_MOVED_PERM \ 102 || (xyz) == HTTP_MOVED_TEMP \ 103 || (xyz) == HTTP_TEMP_REDIRECT \ 104 || (xyz) == HTTP_SEE_OTHER) 105 106 #define HTTP_ERROR(xyz) ((xyz) > 400 && (xyz) < 599) 107 108 109 /***************************************************************************** 110 * I/O functions for decoding chunked streams 111 */ 112 113 struct httpio 114 { 115 conn_t *conn; /* connection */ 116 int chunked; /* chunked mode */ 117 char *buf; /* chunk buffer */ 118 size_t bufsize; /* size of chunk buffer */ 119 ssize_t buflen; /* amount of data currently in buffer */ 120 int bufpos; /* current read offset in buffer */ 121 int eof; /* end-of-file flag */ 122 int error; /* error flag */ 123 size_t chunksize; /* remaining size of current chunk */ 124 #ifndef NDEBUG 125 size_t total; 126 #endif 127 }; 128 129 /* 130 * Get next chunk header 131 */ 132 static int 133 http_new_chunk(struct httpio *io) 134 { 135 char *p; 136 137 if (fetch_getln(io->conn) == -1) 138 return (-1); 139 140 if (io->conn->buflen < 2 || !isxdigit((unsigned char)*io->conn->buf)) 141 return (-1); 142 143 for (p = io->conn->buf; *p && !isspace((unsigned char)*p); ++p) { 144 if (*p == ';') 145 break; 146 if (!isxdigit((unsigned char)*p)) 147 return (-1); 148 if (isdigit((unsigned char)*p)) { 149 io->chunksize = io->chunksize * 16 + 150 *p - '0'; 151 } else { 152 io->chunksize = io->chunksize * 16 + 153 10 + tolower((unsigned char)*p) - 'a'; 154 } 155 } 156 157 #ifndef NDEBUG 158 if (fetchDebug) { 159 io->total += io->chunksize; 160 if (io->chunksize == 0) 161 fprintf(stderr, "%s(): end of last chunk\n", __func__); 162 else 163 fprintf(stderr, "%s(): new chunk: %lu (%lu)\n", 164 __func__, (unsigned long)io->chunksize, 165 (unsigned long)io->total); 166 } 167 #endif 168 169 return (io->chunksize); 170 } 171 172 /* 173 * Grow the input buffer to at least len bytes 174 */ 175 static inline int 176 http_growbuf(struct httpio *io, size_t len) 177 { 178 char *tmp; 179 180 if (io->bufsize >= len) 181 return (0); 182 183 if ((tmp = realloc(io->buf, len)) == NULL) 184 return (-1); 185 io->buf = tmp; 186 io->bufsize = len; 187 return (0); 188 } 189 190 /* 191 * Fill the input buffer, do chunk decoding on the fly 192 */ 193 static int 194 http_fillbuf(struct httpio *io, size_t len) 195 { 196 if (io->error) 197 return (-1); 198 if (io->eof) 199 return (0); 200 201 if (io->chunked == 0) { 202 if (http_growbuf(io, len) == -1) 203 return (-1); 204 if ((io->buflen = fetch_read(io->conn, io->buf, len)) == -1) { 205 io->error = 1; 206 return (-1); 207 } 208 io->bufpos = 0; 209 return (io->buflen); 210 } 211 212 if (io->chunksize == 0) { 213 switch (http_new_chunk(io)) { 214 case -1: 215 io->error = 1; 216 return (-1); 217 case 0: 218 io->eof = 1; 219 return (0); 220 } 221 } 222 223 if (len > io->chunksize) 224 len = io->chunksize; 225 if (http_growbuf(io, len) == -1) 226 return (-1); 227 if ((io->buflen = fetch_read(io->conn, io->buf, len)) == -1) { 228 io->error = 1; 229 return (-1); 230 } 231 io->chunksize -= io->buflen; 232 233 if (io->chunksize == 0) { 234 char endl[2]; 235 236 if (fetch_read(io->conn, endl, 2) != 2 || 237 endl[0] != '\r' || endl[1] != '\n') 238 return (-1); 239 } 240 241 io->bufpos = 0; 242 243 return (io->buflen); 244 } 245 246 /* 247 * Read function 248 */ 249 static int 250 http_readfn(void *v, char *buf, int len) 251 { 252 struct httpio *io = (struct httpio *)v; 253 int l, pos; 254 255 if (io->error) 256 return (-1); 257 if (io->eof) 258 return (0); 259 260 for (pos = 0; len > 0; pos += l, len -= l) { 261 /* empty buffer */ 262 if (!io->buf || io->bufpos == io->buflen) 263 if (http_fillbuf(io, len) < 1) 264 break; 265 l = io->buflen - io->bufpos; 266 if (len < l) 267 l = len; 268 memcpy(buf + pos, io->buf + io->bufpos, l); 269 io->bufpos += l; 270 } 271 272 if (!pos && io->error) 273 return (-1); 274 return (pos); 275 } 276 277 /* 278 * Write function 279 */ 280 static int 281 http_writefn(void *v, const char *buf, int len) 282 { 283 struct httpio *io = (struct httpio *)v; 284 285 return (fetch_write(io->conn, buf, len)); 286 } 287 288 /* 289 * Close function 290 */ 291 static int 292 http_closefn(void *v) 293 { 294 struct httpio *io = (struct httpio *)v; 295 int r; 296 297 r = fetch_close(io->conn); 298 if (io->buf) 299 free(io->buf); 300 free(io); 301 return (r); 302 } 303 304 /* 305 * Wrap a file descriptor up 306 */ 307 static FILE * 308 http_funopen(conn_t *conn, int chunked) 309 { 310 struct httpio *io; 311 FILE *f; 312 313 if ((io = calloc(1, sizeof(*io))) == NULL) { 314 fetch_syserr(); 315 return (NULL); 316 } 317 io->conn = conn; 318 io->chunked = chunked; 319 f = funopen(io, http_readfn, http_writefn, NULL, http_closefn); 320 if (f == NULL) { 321 fetch_syserr(); 322 free(io); 323 return (NULL); 324 } 325 return (f); 326 } 327 328 329 /***************************************************************************** 330 * Helper functions for talking to the server and parsing its replies 331 */ 332 333 /* Header types */ 334 typedef enum { 335 hdr_syserror = -2, 336 hdr_error = -1, 337 hdr_end = 0, 338 hdr_unknown = 1, 339 hdr_content_length, 340 hdr_content_range, 341 hdr_last_modified, 342 hdr_location, 343 hdr_transfer_encoding, 344 hdr_www_authenticate 345 } hdr_t; 346 347 /* Names of interesting headers */ 348 static struct { 349 hdr_t num; 350 const char *name; 351 } hdr_names[] = { 352 { hdr_content_length, "Content-Length" }, 353 { hdr_content_range, "Content-Range" }, 354 { hdr_last_modified, "Last-Modified" }, 355 { hdr_location, "Location" }, 356 { hdr_transfer_encoding, "Transfer-Encoding" }, 357 { hdr_www_authenticate, "WWW-Authenticate" }, 358 { hdr_unknown, NULL }, 359 }; 360 361 /* 362 * Send a formatted line; optionally echo to terminal 363 */ 364 static int 365 http_cmd(conn_t *conn, const char *fmt, ...) 366 { 367 va_list ap; 368 size_t len; 369 char *msg; 370 int r; 371 372 va_start(ap, fmt); 373 len = vasprintf(&msg, fmt, ap); 374 va_end(ap); 375 376 if (msg == NULL) { 377 errno = ENOMEM; 378 fetch_syserr(); 379 return (-1); 380 } 381 382 r = fetch_putln(conn, msg, len); 383 free(msg); 384 385 if (r == -1) { 386 fetch_syserr(); 387 return (-1); 388 } 389 390 return (0); 391 } 392 393 /* 394 * Get and parse status line 395 */ 396 static int 397 http_get_reply(conn_t *conn) 398 { 399 char *p; 400 401 if (fetch_getln(conn) == -1) 402 return (-1); 403 /* 404 * A valid status line looks like "HTTP/m.n xyz reason" where m 405 * and n are the major and minor protocol version numbers and xyz 406 * is the reply code. 407 * Unfortunately, there are servers out there (NCSA 1.5.1, to name 408 * just one) that do not send a version number, so we can't rely 409 * on finding one, but if we do, insist on it being 1.0 or 1.1. 410 * We don't care about the reason phrase. 411 */ 412 if (strncmp(conn->buf, "HTTP", 4) != 0) 413 return (HTTP_PROTOCOL_ERROR); 414 p = conn->buf + 4; 415 if (*p == '/') { 416 if (p[1] != '1' || p[2] != '.' || (p[3] != '0' && p[3] != '1')) 417 return (HTTP_PROTOCOL_ERROR); 418 p += 4; 419 } 420 if (*p != ' ' || 421 !isdigit((unsigned char)p[1]) || 422 !isdigit((unsigned char)p[2]) || 423 !isdigit((unsigned char)p[3])) 424 return (HTTP_PROTOCOL_ERROR); 425 426 conn->err = (p[1] - '0') * 100 + (p[2] - '0') * 10 + (p[3] - '0'); 427 return (conn->err); 428 } 429 430 /* 431 * Check a header; if the type matches the given string, return a pointer 432 * to the beginning of the value. 433 */ 434 static const char * 435 http_match(const char *str, const char *hdr) 436 { 437 while (*str && *hdr && 438 tolower((unsigned char)*str++) == tolower((unsigned char)*hdr++)) 439 /* nothing */; 440 if (*str || *hdr != ':') 441 return (NULL); 442 while (*hdr && isspace((unsigned char)*++hdr)) 443 /* nothing */; 444 return (hdr); 445 } 446 447 /* 448 * Get the next header and return the appropriate symbolic code. 449 */ 450 static hdr_t 451 http_next_header(conn_t *conn, const char **p) 452 { 453 int i; 454 455 if (fetch_getln(conn) == -1) 456 return (hdr_syserror); 457 while (conn->buflen && isspace((unsigned char)conn->buf[conn->buflen - 1])) 458 conn->buflen--; 459 conn->buf[conn->buflen] = '\0'; 460 if (conn->buflen == 0) 461 return (hdr_end); 462 /* 463 * We could check for malformed headers but we don't really care. 464 * A valid header starts with a token immediately followed by a 465 * colon; a token is any sequence of non-control, non-whitespace 466 * characters except "()<>@,;:\\\"{}". 467 */ 468 for (i = 0; hdr_names[i].num != hdr_unknown; i++) 469 if ((*p = http_match(hdr_names[i].name, conn->buf)) != NULL) 470 return (hdr_names[i].num); 471 return (hdr_unknown); 472 } 473 474 /* 475 * Parse a last-modified header 476 */ 477 static int 478 http_parse_mtime(const char *p, time_t *mtime) 479 { 480 char locale[64], *r; 481 struct tm tm; 482 483 strncpy(locale, setlocale(LC_TIME, NULL), sizeof(locale)); 484 setlocale(LC_TIME, "C"); 485 r = strptime(p, "%a, %d %b %Y %H:%M:%S GMT", &tm); 486 /* XXX should add support for date-2 and date-3 */ 487 setlocale(LC_TIME, locale); 488 if (r == NULL) 489 return (-1); 490 DEBUG(fprintf(stderr, "last modified: [%04d-%02d-%02d " 491 "%02d:%02d:%02d]\n", 492 tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, 493 tm.tm_hour, tm.tm_min, tm.tm_sec)); 494 *mtime = timegm(&tm); 495 return (0); 496 } 497 498 /* 499 * Parse a content-length header 500 */ 501 static int 502 http_parse_length(const char *p, off_t *length) 503 { 504 off_t len; 505 506 for (len = 0; *p && isdigit((unsigned char)*p); ++p) 507 len = len * 10 + (*p - '0'); 508 if (*p) 509 return (-1); 510 DEBUG(fprintf(stderr, "content length: [%lld]\n", 511 (long long)len)); 512 *length = len; 513 return (0); 514 } 515 516 /* 517 * Parse a content-range header 518 */ 519 static int 520 http_parse_range(const char *p, off_t *offset, off_t *length, off_t *size) 521 { 522 off_t first, last, len; 523 524 if (strncasecmp(p, "bytes ", 6) != 0) 525 return (-1); 526 p += 6; 527 if (*p == '*') { 528 first = last = -1; 529 ++p; 530 } else { 531 for (first = 0; *p && isdigit((unsigned char)*p); ++p) 532 first = first * 10 + *p - '0'; 533 if (*p != '-') 534 return (-1); 535 for (last = 0, ++p; *p && isdigit((unsigned char)*p); ++p) 536 last = last * 10 + *p - '0'; 537 } 538 if (first > last || *p != '/') 539 return (-1); 540 for (len = 0, ++p; *p && isdigit((unsigned char)*p); ++p) 541 len = len * 10 + *p - '0'; 542 if (*p || len < last - first + 1) 543 return (-1); 544 if (first == -1) { 545 DEBUG(fprintf(stderr, "content range: [*/%lld]\n", 546 (long long)len)); 547 *length = 0; 548 } else { 549 DEBUG(fprintf(stderr, "content range: [%lld-%lld/%lld]\n", 550 (long long)first, (long long)last, (long long)len)); 551 *length = last - first + 1; 552 } 553 *offset = first; 554 *size = len; 555 return (0); 556 } 557 558 559 /***************************************************************************** 560 * Helper functions for authorization 561 */ 562 563 /* 564 * Base64 encoding 565 */ 566 static char * 567 http_base64(const char *src) 568 { 569 static const char base64[] = 570 "ABCDEFGHIJKLMNOPQRSTUVWXYZ" 571 "abcdefghijklmnopqrstuvwxyz" 572 "0123456789+/"; 573 char *str, *dst; 574 size_t l; 575 int t, r; 576 577 l = strlen(src); 578 if ((str = malloc(((l + 2) / 3) * 4 + 1)) == NULL) 579 return (NULL); 580 dst = str; 581 r = 0; 582 583 while (l >= 3) { 584 t = (src[0] << 16) | (src[1] << 8) | src[2]; 585 dst[0] = base64[(t >> 18) & 0x3f]; 586 dst[1] = base64[(t >> 12) & 0x3f]; 587 dst[2] = base64[(t >> 6) & 0x3f]; 588 dst[3] = base64[(t >> 0) & 0x3f]; 589 src += 3; l -= 3; 590 dst += 4; r += 4; 591 } 592 593 switch (l) { 594 case 2: 595 t = (src[0] << 16) | (src[1] << 8); 596 dst[0] = base64[(t >> 18) & 0x3f]; 597 dst[1] = base64[(t >> 12) & 0x3f]; 598 dst[2] = base64[(t >> 6) & 0x3f]; 599 dst[3] = '='; 600 dst += 4; 601 r += 4; 602 break; 603 case 1: 604 t = src[0] << 16; 605 dst[0] = base64[(t >> 18) & 0x3f]; 606 dst[1] = base64[(t >> 12) & 0x3f]; 607 dst[2] = dst[3] = '='; 608 dst += 4; 609 r += 4; 610 break; 611 case 0: 612 break; 613 } 614 615 *dst = 0; 616 return (str); 617 } 618 619 /* 620 * Encode username and password 621 */ 622 static int 623 http_basic_auth(conn_t *conn, const char *hdr, const char *usr, const char *pwd) 624 { 625 char *upw, *auth; 626 int r; 627 628 DEBUG(fprintf(stderr, "usr: [%s]\n", usr)); 629 DEBUG(fprintf(stderr, "pwd: [%s]\n", pwd)); 630 if (asprintf(&upw, "%s:%s", usr, pwd) == -1) 631 return (-1); 632 auth = http_base64(upw); 633 free(upw); 634 if (auth == NULL) 635 return (-1); 636 r = http_cmd(conn, "%s: Basic %s", hdr, auth); 637 free(auth); 638 return (r); 639 } 640 641 /* 642 * Send an authorization header 643 */ 644 static int 645 http_authorize(conn_t *conn, const char *hdr, const char *p) 646 { 647 /* basic authorization */ 648 if (strncasecmp(p, "basic:", 6) == 0) { 649 char *user, *pwd, *str; 650 int r; 651 652 /* skip realm */ 653 for (p += 6; *p && *p != ':'; ++p) 654 /* nothing */ ; 655 if (!*p || strchr(++p, ':') == NULL) 656 return (-1); 657 if ((str = strdup(p)) == NULL) 658 return (-1); /* XXX */ 659 user = str; 660 pwd = strchr(str, ':'); 661 *pwd++ = '\0'; 662 r = http_basic_auth(conn, hdr, user, pwd); 663 free(str); 664 return (r); 665 } 666 return (-1); 667 } 668 669 670 /***************************************************************************** 671 * Helper functions for connecting to a server or proxy 672 */ 673 674 /* 675 * Connect to the correct HTTP server or proxy. 676 */ 677 static conn_t * 678 http_connect(struct url *URL, struct url *purl, const char *flags) 679 { 680 conn_t *conn; 681 int verbose; 682 int af, val; 683 684 #ifdef INET6 685 af = AF_UNSPEC; 686 #else 687 af = AF_INET; 688 #endif 689 690 verbose = CHECK_FLAG('v'); 691 if (CHECK_FLAG('4')) 692 af = AF_INET; 693 #ifdef INET6 694 else if (CHECK_FLAG('6')) 695 af = AF_INET6; 696 #endif 697 698 if (purl && strcasecmp(URL->scheme, SCHEME_HTTPS) != 0) { 699 URL = purl; 700 } else if (strcasecmp(URL->scheme, SCHEME_FTP) == 0) { 701 /* can't talk http to an ftp server */ 702 /* XXX should set an error code */ 703 return (NULL); 704 } 705 706 if ((conn = fetch_connect(URL->host, URL->port, af, verbose)) == NULL) 707 /* fetch_connect() has already set an error code */ 708 return (NULL); 709 if (strcasecmp(URL->scheme, SCHEME_HTTPS) == 0 && 710 fetch_ssl(conn, verbose) == -1) { 711 fetch_close(conn); 712 /* grrr */ 713 errno = EAUTH; 714 fetch_syserr(); 715 return (NULL); 716 } 717 718 val = 1; 719 setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, sizeof(val)); 720 721 return (conn); 722 } 723 724 static struct url * 725 http_get_proxy(struct url * url, const char *flags) 726 { 727 struct url *purl; 728 char *p; 729 730 if (flags != NULL && strchr(flags, 'd') != NULL) 731 return (NULL); 732 if (fetch_no_proxy_match(url->host)) 733 return (NULL); 734 if (((p = getenv("HTTP_PROXY")) || (p = getenv("http_proxy"))) && 735 *p && (purl = fetchParseURL(p))) { 736 if (!*purl->scheme) 737 strcpy(purl->scheme, SCHEME_HTTP); 738 if (!purl->port) 739 purl->port = fetch_default_proxy_port(purl->scheme); 740 if (strcasecmp(purl->scheme, SCHEME_HTTP) == 0) 741 return (purl); 742 fetchFreeURL(purl); 743 } 744 return (NULL); 745 } 746 747 static void 748 http_print_html(FILE *out, FILE *in) 749 { 750 size_t len; 751 char *line, *p, *q; 752 int comment, tag; 753 754 comment = tag = 0; 755 while ((line = fgetln(in, &len)) != NULL) { 756 while (len && isspace((unsigned char)line[len - 1])) 757 --len; 758 for (p = q = line; q < line + len; ++q) { 759 if (comment && *q == '-') { 760 if (q + 2 < line + len && 761 strcmp(q, "-->") == 0) { 762 tag = comment = 0; 763 q += 2; 764 } 765 } else if (tag && !comment && *q == '>') { 766 p = q + 1; 767 tag = 0; 768 } else if (!tag && *q == '<') { 769 if (q > p) 770 fwrite(p, q - p, 1, out); 771 tag = 1; 772 if (q + 3 < line + len && 773 strcmp(q, "<!--") == 0) { 774 comment = 1; 775 q += 3; 776 } 777 } 778 } 779 if (!tag && q > p) 780 fwrite(p, q - p, 1, out); 781 fputc('\n', out); 782 } 783 } 784 785 786 /***************************************************************************** 787 * Core 788 */ 789 790 /* 791 * Send a request and process the reply 792 * 793 * XXX This function is way too long, the do..while loop should be split 794 * XXX off into a separate function. 795 */ 796 FILE * 797 http_request(struct url *URL, const char *op, struct url_stat *us, 798 struct url *purl, const char *flags) 799 { 800 conn_t *conn; 801 struct url *url, *new; 802 int chunked, direct, need_auth, noredirect, verbose; 803 int e, i, n, val; 804 off_t offset, clength, length, size; 805 time_t mtime; 806 const char *p; 807 FILE *f; 808 hdr_t h; 809 char hbuf[MAXHOSTNAMELEN + 7], *host; 810 811 direct = CHECK_FLAG('d'); 812 noredirect = CHECK_FLAG('A'); 813 verbose = CHECK_FLAG('v'); 814 815 if (direct && purl) { 816 fetchFreeURL(purl); 817 purl = NULL; 818 } 819 820 /* try the provided URL first */ 821 url = URL; 822 823 /* if the A flag is set, we only get one try */ 824 n = noredirect ? 1 : MAX_REDIRECT; 825 i = 0; 826 827 e = HTTP_PROTOCOL_ERROR; 828 need_auth = 0; 829 do { 830 new = NULL; 831 chunked = 0; 832 offset = 0; 833 clength = -1; 834 length = -1; 835 size = -1; 836 mtime = 0; 837 838 /* check port */ 839 if (!url->port) 840 url->port = fetch_default_port(url->scheme); 841 842 /* were we redirected to an FTP URL? */ 843 if (purl == NULL && strcmp(url->scheme, SCHEME_FTP) == 0) { 844 if (strcmp(op, "GET") == 0) 845 return (ftp_request(url, "RETR", us, purl, flags)); 846 else if (strcmp(op, "HEAD") == 0) 847 return (ftp_request(url, "STAT", us, purl, flags)); 848 } 849 850 /* connect to server or proxy */ 851 if ((conn = http_connect(url, purl, flags)) == NULL) 852 goto ouch; 853 854 host = url->host; 855 #ifdef INET6 856 if (strchr(url->host, ':')) { 857 snprintf(hbuf, sizeof(hbuf), "[%s]", url->host); 858 host = hbuf; 859 } 860 #endif 861 if (url->port != fetch_default_port(url->scheme)) { 862 if (host != hbuf) { 863 strcpy(hbuf, host); 864 host = hbuf; 865 } 866 snprintf(hbuf + strlen(hbuf), 867 sizeof(hbuf) - strlen(hbuf), ":%d", url->port); 868 } 869 870 /* send request */ 871 if (verbose) 872 fetch_info("requesting %s://%s%s", 873 url->scheme, host, url->doc); 874 if (purl) { 875 http_cmd(conn, "%s %s://%s%s HTTP/1.1", 876 op, url->scheme, host, url->doc); 877 } else { 878 http_cmd(conn, "%s %s HTTP/1.1", 879 op, url->doc); 880 } 881 882 /* virtual host */ 883 http_cmd(conn, "Host: %s", host); 884 885 /* proxy authorization */ 886 if (purl) { 887 if (*purl->user || *purl->pwd) 888 http_basic_auth(conn, "Proxy-Authorization", 889 purl->user, purl->pwd); 890 else if ((p = getenv("HTTP_PROXY_AUTH")) != NULL && *p != '\0') 891 http_authorize(conn, "Proxy-Authorization", p); 892 } 893 894 /* server authorization */ 895 if (need_auth || *url->user || *url->pwd) { 896 if (*url->user || *url->pwd) 897 http_basic_auth(conn, "Authorization", url->user, url->pwd); 898 else if ((p = getenv("HTTP_AUTH")) != NULL && *p != '\0') 899 http_authorize(conn, "Authorization", p); 900 else if (fetchAuthMethod && fetchAuthMethod(url) == 0) { 901 http_basic_auth(conn, "Authorization", url->user, url->pwd); 902 } else { 903 http_seterr(HTTP_NEED_AUTH); 904 goto ouch; 905 } 906 } 907 908 /* other headers */ 909 if ((p = getenv("HTTP_REFERER")) != NULL && *p != '\0') { 910 if (strcasecmp(p, "auto") == 0) 911 http_cmd(conn, "Referer: %s://%s%s", 912 url->scheme, host, url->doc); 913 else 914 http_cmd(conn, "Referer: %s", p); 915 } 916 if ((p = getenv("HTTP_USER_AGENT")) != NULL && *p != '\0') 917 http_cmd(conn, "User-Agent: %s", p); 918 else 919 http_cmd(conn, "User-Agent: %s " _LIBFETCH_VER, getprogname()); 920 if (url->offset > 0) 921 http_cmd(conn, "Range: bytes=%lld-", (long long)url->offset); 922 http_cmd(conn, "Connection: close"); 923 http_cmd(conn, ""); 924 925 /* 926 * Force the queued request to be dispatched. Normally, one 927 * would do this with shutdown(2) but squid proxies can be 928 * configured to disallow such half-closed connections. To 929 * be compatible with such configurations, fiddle with socket 930 * options to force the pending data to be written. 931 */ 932 val = 0; 933 setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, 934 sizeof(val)); 935 val = 1; 936 setsockopt(conn->sd, IPPROTO_TCP, TCP_NODELAY, &val, 937 sizeof(val)); 938 939 /* get reply */ 940 switch (http_get_reply(conn)) { 941 case HTTP_OK: 942 case HTTP_PARTIAL: 943 /* fine */ 944 break; 945 case HTTP_MOVED_PERM: 946 case HTTP_MOVED_TEMP: 947 case HTTP_SEE_OTHER: 948 /* 949 * Not so fine, but we still have to read the 950 * headers to get the new location. 951 */ 952 break; 953 case HTTP_NEED_AUTH: 954 if (need_auth) { 955 /* 956 * We already sent out authorization code, 957 * so there's nothing more we can do. 958 */ 959 http_seterr(conn->err); 960 goto ouch; 961 } 962 /* try again, but send the password this time */ 963 if (verbose) 964 fetch_info("server requires authorization"); 965 break; 966 case HTTP_NEED_PROXY_AUTH: 967 /* 968 * If we're talking to a proxy, we already sent 969 * our proxy authorization code, so there's 970 * nothing more we can do. 971 */ 972 http_seterr(conn->err); 973 goto ouch; 974 case HTTP_BAD_RANGE: 975 /* 976 * This can happen if we ask for 0 bytes because 977 * we already have the whole file. Consider this 978 * a success for now, and check sizes later. 979 */ 980 break; 981 case HTTP_PROTOCOL_ERROR: 982 /* fall through */ 983 case -1: 984 fetch_syserr(); 985 goto ouch; 986 default: 987 http_seterr(conn->err); 988 if (!verbose) 989 goto ouch; 990 /* fall through so we can get the full error message */ 991 } 992 993 /* get headers */ 994 do { 995 switch ((h = http_next_header(conn, &p))) { 996 case hdr_syserror: 997 fetch_syserr(); 998 goto ouch; 999 case hdr_error: 1000 http_seterr(HTTP_PROTOCOL_ERROR); 1001 goto ouch; 1002 case hdr_content_length: 1003 http_parse_length(p, &clength); 1004 break; 1005 case hdr_content_range: 1006 http_parse_range(p, &offset, &length, &size); 1007 break; 1008 case hdr_last_modified: 1009 http_parse_mtime(p, &mtime); 1010 break; 1011 case hdr_location: 1012 if (!HTTP_REDIRECT(conn->err)) 1013 break; 1014 if (new) 1015 free(new); 1016 if (verbose) 1017 fetch_info("%d redirect to %s", conn->err, p); 1018 if (*p == '/') 1019 /* absolute path */ 1020 new = fetchMakeURL(url->scheme, url->host, url->port, p, 1021 url->user, url->pwd); 1022 else 1023 new = fetchParseURL(p); 1024 if (new == NULL) { 1025 /* XXX should set an error code */ 1026 DEBUG(fprintf(stderr, "failed to parse new URL\n")); 1027 goto ouch; 1028 } 1029 if (!*new->user && !*new->pwd) { 1030 strcpy(new->user, url->user); 1031 strcpy(new->pwd, url->pwd); 1032 } 1033 new->offset = url->offset; 1034 new->length = url->length; 1035 break; 1036 case hdr_transfer_encoding: 1037 /* XXX weak test*/ 1038 chunked = (strcasecmp(p, "chunked") == 0); 1039 break; 1040 case hdr_www_authenticate: 1041 if (conn->err != HTTP_NEED_AUTH) 1042 break; 1043 /* if we were smarter, we'd check the method and realm */ 1044 break; 1045 case hdr_end: 1046 /* fall through */ 1047 case hdr_unknown: 1048 /* ignore */ 1049 break; 1050 } 1051 } while (h > hdr_end); 1052 1053 /* we need to provide authentication */ 1054 if (conn->err == HTTP_NEED_AUTH) { 1055 e = conn->err; 1056 need_auth = 1; 1057 fetch_close(conn); 1058 conn = NULL; 1059 continue; 1060 } 1061 1062 /* requested range not satisfiable */ 1063 if (conn->err == HTTP_BAD_RANGE) { 1064 if (url->offset == size && url->length == 0) { 1065 /* asked for 0 bytes; fake it */ 1066 offset = url->offset; 1067 conn->err = HTTP_OK; 1068 break; 1069 } else { 1070 http_seterr(conn->err); 1071 goto ouch; 1072 } 1073 } 1074 1075 /* we have a hit or an error */ 1076 if (conn->err == HTTP_OK || conn->err == HTTP_PARTIAL || HTTP_ERROR(conn->err)) 1077 break; 1078 1079 /* all other cases: we got a redirect */ 1080 e = conn->err; 1081 need_auth = 0; 1082 fetch_close(conn); 1083 conn = NULL; 1084 if (!new) { 1085 DEBUG(fprintf(stderr, "redirect with no new location\n")); 1086 break; 1087 } 1088 if (url != URL) 1089 fetchFreeURL(url); 1090 url = new; 1091 } while (++i < n); 1092 1093 /* we failed, or ran out of retries */ 1094 if (conn == NULL) { 1095 http_seterr(e); 1096 goto ouch; 1097 } 1098 1099 DEBUG(fprintf(stderr, "offset %lld, length %lld," 1100 " size %lld, clength %lld\n", 1101 (long long)offset, (long long)length, 1102 (long long)size, (long long)clength)); 1103 1104 /* check for inconsistencies */ 1105 if (clength != -1 && length != -1 && clength != length) { 1106 http_seterr(HTTP_PROTOCOL_ERROR); 1107 goto ouch; 1108 } 1109 if (clength == -1) 1110 clength = length; 1111 if (clength != -1) 1112 length = offset + clength; 1113 if (length != -1 && size != -1 && length != size) { 1114 http_seterr(HTTP_PROTOCOL_ERROR); 1115 goto ouch; 1116 } 1117 if (size == -1) 1118 size = length; 1119 1120 /* fill in stats */ 1121 if (us) { 1122 us->size = size; 1123 us->atime = us->mtime = mtime; 1124 } 1125 1126 /* too far? */ 1127 if (URL->offset > 0 && offset > URL->offset) { 1128 http_seterr(HTTP_PROTOCOL_ERROR); 1129 goto ouch; 1130 } 1131 1132 /* report back real offset and size */ 1133 URL->offset = offset; 1134 URL->length = clength; 1135 1136 /* wrap it up in a FILE */ 1137 if ((f = http_funopen(conn, chunked)) == NULL) { 1138 fetch_syserr(); 1139 goto ouch; 1140 } 1141 1142 if (url != URL) 1143 fetchFreeURL(url); 1144 if (purl) 1145 fetchFreeURL(purl); 1146 1147 if (HTTP_ERROR(conn->err)) { 1148 http_print_html(stderr, f); 1149 fclose(f); 1150 f = NULL; 1151 } 1152 1153 return (f); 1154 1155 ouch: 1156 if (url != URL) 1157 fetchFreeURL(url); 1158 if (purl) 1159 fetchFreeURL(purl); 1160 if (conn != NULL) 1161 fetch_close(conn); 1162 return (NULL); 1163 } 1164 1165 1166 /***************************************************************************** 1167 * Entry points 1168 */ 1169 1170 /* 1171 * Retrieve and stat a file by HTTP 1172 */ 1173 FILE * 1174 fetchXGetHTTP(struct url *URL, struct url_stat *us, const char *flags) 1175 { 1176 return (http_request(URL, "GET", us, http_get_proxy(URL, flags), flags)); 1177 } 1178 1179 /* 1180 * Retrieve a file by HTTP 1181 */ 1182 FILE * 1183 fetchGetHTTP(struct url *URL, const char *flags) 1184 { 1185 return (fetchXGetHTTP(URL, NULL, flags)); 1186 } 1187 1188 /* 1189 * Store a file by HTTP 1190 */ 1191 FILE * 1192 fetchPutHTTP(struct url *URL __unused, const char *flags __unused) 1193 { 1194 warnx("fetchPutHTTP(): not implemented"); 1195 return (NULL); 1196 } 1197 1198 /* 1199 * Get an HTTP document's metadata 1200 */ 1201 int 1202 fetchStatHTTP(struct url *URL, struct url_stat *us, const char *flags) 1203 { 1204 FILE *f; 1205 1206 f = http_request(URL, "HEAD", us, http_get_proxy(URL, flags), flags); 1207 if (f == NULL) 1208 return (-1); 1209 fclose(f); 1210 return (0); 1211 } 1212 1213 /* 1214 * List a directory 1215 */ 1216 struct url_ent * 1217 fetchListHTTP(struct url *url __unused, const char *flags __unused) 1218 { 1219 warnx("fetchListHTTP(): not implemented"); 1220 return (NULL); 1221 } 1222