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 #include <sys/time.h> 67 68 #include <ctype.h> 69 #include <err.h> 70 #include <errno.h> 71 #include <locale.h> 72 #include <netdb.h> 73 #include <stdarg.h> 74 #include <stdio.h> 75 #include <stdlib.h> 76 #include <string.h> 77 #include <time.h> 78 #include <unistd.h> 79 80 #include <netinet/in.h> 81 #include <netinet/tcp.h> 82 83 #include "fetch.h" 84 #include "common.h" 85 #include "httperr.h" 86 87 /* Maximum number of redirects to follow */ 88 #define MAX_REDIRECT 5 89 90 /* Symbolic names for reply codes we care about */ 91 #define HTTP_OK 200 92 #define HTTP_PARTIAL 206 93 #define HTTP_MOVED_PERM 301 94 #define HTTP_MOVED_TEMP 302 95 #define HTTP_SEE_OTHER 303 96 #define HTTP_NOT_MODIFIED 304 97 #define HTTP_TEMP_REDIRECT 307 98 #define HTTP_NEED_AUTH 401 99 #define HTTP_NEED_PROXY_AUTH 407 100 #define HTTP_BAD_RANGE 416 101 #define HTTP_PROTOCOL_ERROR 999 102 103 #define HTTP_REDIRECT(xyz) ((xyz) == HTTP_MOVED_PERM \ 104 || (xyz) == HTTP_MOVED_TEMP \ 105 || (xyz) == HTTP_TEMP_REDIRECT \ 106 || (xyz) == HTTP_SEE_OTHER) 107 108 #define HTTP_ERROR(xyz) ((xyz) > 400 && (xyz) < 599) 109 110 111 /***************************************************************************** 112 * I/O functions for decoding chunked streams 113 */ 114 115 struct httpio 116 { 117 conn_t *conn; /* connection */ 118 int chunked; /* chunked mode */ 119 char *buf; /* chunk buffer */ 120 size_t bufsize; /* size of chunk buffer */ 121 ssize_t buflen; /* amount of data currently in buffer */ 122 int bufpos; /* current read offset in buffer */ 123 int eof; /* end-of-file flag */ 124 int error; /* error flag */ 125 size_t chunksize; /* remaining size of current chunk */ 126 #ifndef NDEBUG 127 size_t total; 128 #endif 129 }; 130 131 /* 132 * Get next chunk header 133 */ 134 static int 135 http_new_chunk(struct httpio *io) 136 { 137 char *p; 138 139 if (fetch_getln(io->conn) == -1) 140 return (-1); 141 142 if (io->conn->buflen < 2 || !isxdigit((unsigned char)*io->conn->buf)) 143 return (-1); 144 145 for (p = io->conn->buf; *p && !isspace((unsigned char)*p); ++p) { 146 if (*p == ';') 147 break; 148 if (!isxdigit((unsigned char)*p)) 149 return (-1); 150 if (isdigit((unsigned char)*p)) { 151 io->chunksize = io->chunksize * 16 + 152 *p - '0'; 153 } else { 154 io->chunksize = io->chunksize * 16 + 155 10 + tolower((unsigned char)*p) - 'a'; 156 } 157 } 158 159 #ifndef NDEBUG 160 if (fetchDebug) { 161 io->total += io->chunksize; 162 if (io->chunksize == 0) 163 fprintf(stderr, "%s(): end of last chunk\n", __func__); 164 else 165 fprintf(stderr, "%s(): new chunk: %lu (%lu)\n", 166 __func__, (unsigned long)io->chunksize, 167 (unsigned long)io->total); 168 } 169 #endif 170 171 return (io->chunksize); 172 } 173 174 /* 175 * Grow the input buffer to at least len bytes 176 */ 177 static inline int 178 http_growbuf(struct httpio *io, size_t len) 179 { 180 char *tmp; 181 182 if (io->bufsize >= len) 183 return (0); 184 185 if ((tmp = realloc(io->buf, len)) == NULL) 186 return (-1); 187 io->buf = tmp; 188 io->bufsize = len; 189 return (0); 190 } 191 192 /* 193 * Fill the input buffer, do chunk decoding on the fly 194 */ 195 static int 196 http_fillbuf(struct httpio *io, size_t len) 197 { 198 if (io->error) 199 return (-1); 200 if (io->eof) 201 return (0); 202 203 if (io->chunked == 0) { 204 if (http_growbuf(io, len) == -1) 205 return (-1); 206 if ((io->buflen = fetch_read(io->conn, io->buf, len)) == -1) { 207 io->error = 1; 208 return (-1); 209 } 210 io->bufpos = 0; 211 return (io->buflen); 212 } 213 214 if (io->chunksize == 0) { 215 switch (http_new_chunk(io)) { 216 case -1: 217 io->error = 1; 218 return (-1); 219 case 0: 220 io->eof = 1; 221 return (0); 222 } 223 } 224 225 if (len > io->chunksize) 226 len = io->chunksize; 227 if (http_growbuf(io, len) == -1) 228 return (-1); 229 if ((io->buflen = fetch_read(io->conn, io->buf, len)) == -1) { 230 io->error = 1; 231 return (-1); 232 } 233 io->chunksize -= io->buflen; 234 235 if (io->chunksize == 0) { 236 char endl[2]; 237 238 if (fetch_read(io->conn, endl, 2) != 2 || 239 endl[0] != '\r' || endl[1] != '\n') 240 return (-1); 241 } 242 243 io->bufpos = 0; 244 245 return (io->buflen); 246 } 247 248 /* 249 * Read function 250 */ 251 static int 252 http_readfn(void *v, char *buf, int len) 253 { 254 struct httpio *io = (struct httpio *)v; 255 int l, pos; 256 257 if (io->error) 258 return (-1); 259 if (io->eof) 260 return (0); 261 262 for (pos = 0; len > 0; pos += l, len -= l) { 263 /* empty buffer */ 264 if (!io->buf || io->bufpos == io->buflen) 265 if (http_fillbuf(io, len) < 1) 266 break; 267 l = io->buflen - io->bufpos; 268 if (len < l) 269 l = len; 270 memcpy(buf + pos, io->buf + io->bufpos, l); 271 io->bufpos += l; 272 } 273 274 if (!pos && io->error) 275 return (-1); 276 return (pos); 277 } 278 279 /* 280 * Write function 281 */ 282 static int 283 http_writefn(void *v, const char *buf, int len) 284 { 285 struct httpio *io = (struct httpio *)v; 286 287 return (fetch_write(io->conn, buf, len)); 288 } 289 290 /* 291 * Close function 292 */ 293 static int 294 http_closefn(void *v) 295 { 296 struct httpio *io = (struct httpio *)v; 297 int r; 298 299 r = fetch_close(io->conn); 300 if (io->buf) 301 free(io->buf); 302 free(io); 303 return (r); 304 } 305 306 /* 307 * Wrap a file descriptor up 308 */ 309 static FILE * 310 http_funopen(conn_t *conn, int chunked) 311 { 312 struct httpio *io; 313 FILE *f; 314 315 if ((io = calloc(1, sizeof(*io))) == NULL) { 316 fetch_syserr(); 317 return (NULL); 318 } 319 io->conn = conn; 320 io->chunked = chunked; 321 f = funopen(io, http_readfn, http_writefn, NULL, http_closefn); 322 if (f == NULL) { 323 fetch_syserr(); 324 free(io); 325 return (NULL); 326 } 327 return (f); 328 } 329 330 331 /***************************************************************************** 332 * Helper functions for talking to the server and parsing its replies 333 */ 334 335 /* Header types */ 336 typedef enum { 337 hdr_syserror = -2, 338 hdr_error = -1, 339 hdr_end = 0, 340 hdr_unknown = 1, 341 hdr_content_length, 342 hdr_content_range, 343 hdr_last_modified, 344 hdr_location, 345 hdr_transfer_encoding, 346 hdr_www_authenticate 347 } hdr_t; 348 349 /* Names of interesting headers */ 350 static struct { 351 hdr_t num; 352 const char *name; 353 } hdr_names[] = { 354 { hdr_content_length, "Content-Length" }, 355 { hdr_content_range, "Content-Range" }, 356 { hdr_last_modified, "Last-Modified" }, 357 { hdr_location, "Location" }, 358 { hdr_transfer_encoding, "Transfer-Encoding" }, 359 { hdr_www_authenticate, "WWW-Authenticate" }, 360 { hdr_unknown, NULL }, 361 }; 362 363 /* 364 * Send a formatted line; optionally echo to terminal 365 */ 366 static int 367 http_cmd(conn_t *conn, const char *fmt, ...) 368 { 369 va_list ap; 370 size_t len; 371 char *msg; 372 int r; 373 374 va_start(ap, fmt); 375 len = vasprintf(&msg, fmt, ap); 376 va_end(ap); 377 378 if (msg == NULL) { 379 errno = ENOMEM; 380 fetch_syserr(); 381 return (-1); 382 } 383 384 r = fetch_putln(conn, msg, len); 385 free(msg); 386 387 if (r == -1) { 388 fetch_syserr(); 389 return (-1); 390 } 391 392 return (0); 393 } 394 395 /* 396 * Get and parse status line 397 */ 398 static int 399 http_get_reply(conn_t *conn) 400 { 401 char *p; 402 403 if (fetch_getln(conn) == -1) 404 return (-1); 405 /* 406 * A valid status line looks like "HTTP/m.n xyz reason" where m 407 * and n are the major and minor protocol version numbers and xyz 408 * is the reply code. 409 * Unfortunately, there are servers out there (NCSA 1.5.1, to name 410 * just one) that do not send a version number, so we can't rely 411 * on finding one, but if we do, insist on it being 1.0 or 1.1. 412 * We don't care about the reason phrase. 413 */ 414 if (strncmp(conn->buf, "HTTP", 4) != 0) 415 return (HTTP_PROTOCOL_ERROR); 416 p = conn->buf + 4; 417 if (*p == '/') { 418 if (p[1] != '1' || p[2] != '.' || (p[3] != '0' && p[3] != '1')) 419 return (HTTP_PROTOCOL_ERROR); 420 p += 4; 421 } 422 if (*p != ' ' || 423 !isdigit((unsigned char)p[1]) || 424 !isdigit((unsigned char)p[2]) || 425 !isdigit((unsigned char)p[3])) 426 return (HTTP_PROTOCOL_ERROR); 427 428 conn->err = (p[1] - '0') * 100 + (p[2] - '0') * 10 + (p[3] - '0'); 429 return (conn->err); 430 } 431 432 /* 433 * Check a header; if the type matches the given string, return a pointer 434 * to the beginning of the value. 435 */ 436 static const char * 437 http_match(const char *str, const char *hdr) 438 { 439 while (*str && *hdr && 440 tolower((unsigned char)*str++) == tolower((unsigned char)*hdr++)) 441 /* nothing */; 442 if (*str || *hdr != ':') 443 return (NULL); 444 while (*hdr && isspace((unsigned char)*++hdr)) 445 /* nothing */; 446 return (hdr); 447 } 448 449 /* 450 * Get the next header and return the appropriate symbolic code. 451 */ 452 static hdr_t 453 http_next_header(conn_t *conn, const char **p) 454 { 455 int i; 456 457 if (fetch_getln(conn) == -1) 458 return (hdr_syserror); 459 while (conn->buflen && isspace((unsigned char)conn->buf[conn->buflen - 1])) 460 conn->buflen--; 461 conn->buf[conn->buflen] = '\0'; 462 if (conn->buflen == 0) 463 return (hdr_end); 464 /* 465 * We could check for malformed headers but we don't really care. 466 * A valid header starts with a token immediately followed by a 467 * colon; a token is any sequence of non-control, non-whitespace 468 * characters except "()<>@,;:\\\"{}". 469 */ 470 for (i = 0; hdr_names[i].num != hdr_unknown; i++) 471 if ((*p = http_match(hdr_names[i].name, conn->buf)) != NULL) 472 return (hdr_names[i].num); 473 return (hdr_unknown); 474 } 475 476 /* 477 * Parse a last-modified header 478 */ 479 static int 480 http_parse_mtime(const char *p, time_t *mtime) 481 { 482 char locale[64], *r; 483 struct tm tm; 484 485 strncpy(locale, setlocale(LC_TIME, NULL), sizeof(locale)); 486 setlocale(LC_TIME, "C"); 487 r = strptime(p, "%a, %d %b %Y %H:%M:%S GMT", &tm); 488 /* XXX should add support for date-2 and date-3 */ 489 setlocale(LC_TIME, locale); 490 if (r == NULL) 491 return (-1); 492 DEBUG(fprintf(stderr, "last modified: [%04d-%02d-%02d " 493 "%02d:%02d:%02d]\n", 494 tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, 495 tm.tm_hour, tm.tm_min, tm.tm_sec)); 496 *mtime = timegm(&tm); 497 return (0); 498 } 499 500 /* 501 * Parse a content-length header 502 */ 503 static int 504 http_parse_length(const char *p, off_t *length) 505 { 506 off_t len; 507 508 for (len = 0; *p && isdigit((unsigned char)*p); ++p) 509 len = len * 10 + (*p - '0'); 510 if (*p) 511 return (-1); 512 DEBUG(fprintf(stderr, "content length: [%lld]\n", 513 (long long)len)); 514 *length = len; 515 return (0); 516 } 517 518 /* 519 * Parse a content-range header 520 */ 521 static int 522 http_parse_range(const char *p, off_t *offset, off_t *length, off_t *size) 523 { 524 off_t first, last, len; 525 526 if (strncasecmp(p, "bytes ", 6) != 0) 527 return (-1); 528 p += 6; 529 if (*p == '*') { 530 first = last = -1; 531 ++p; 532 } else { 533 for (first = 0; *p && isdigit((unsigned char)*p); ++p) 534 first = first * 10 + *p - '0'; 535 if (*p != '-') 536 return (-1); 537 for (last = 0, ++p; *p && isdigit((unsigned char)*p); ++p) 538 last = last * 10 + *p - '0'; 539 } 540 if (first > last || *p != '/') 541 return (-1); 542 for (len = 0, ++p; *p && isdigit((unsigned char)*p); ++p) 543 len = len * 10 + *p - '0'; 544 if (*p || len < last - first + 1) 545 return (-1); 546 if (first == -1) { 547 DEBUG(fprintf(stderr, "content range: [*/%lld]\n", 548 (long long)len)); 549 *length = 0; 550 } else { 551 DEBUG(fprintf(stderr, "content range: [%lld-%lld/%lld]\n", 552 (long long)first, (long long)last, (long long)len)); 553 *length = last - first + 1; 554 } 555 *offset = first; 556 *size = len; 557 return (0); 558 } 559 560 561 /***************************************************************************** 562 * Helper functions for authorization 563 */ 564 565 /* 566 * Base64 encoding 567 */ 568 static char * 569 http_base64(const char *src) 570 { 571 static const char base64[] = 572 "ABCDEFGHIJKLMNOPQRSTUVWXYZ" 573 "abcdefghijklmnopqrstuvwxyz" 574 "0123456789+/"; 575 char *str, *dst; 576 size_t l; 577 int t, r; 578 579 l = strlen(src); 580 if ((str = malloc(((l + 2) / 3) * 4 + 1)) == NULL) 581 return (NULL); 582 dst = str; 583 r = 0; 584 585 while (l >= 3) { 586 t = (src[0] << 16) | (src[1] << 8) | src[2]; 587 dst[0] = base64[(t >> 18) & 0x3f]; 588 dst[1] = base64[(t >> 12) & 0x3f]; 589 dst[2] = base64[(t >> 6) & 0x3f]; 590 dst[3] = base64[(t >> 0) & 0x3f]; 591 src += 3; l -= 3; 592 dst += 4; r += 4; 593 } 594 595 switch (l) { 596 case 2: 597 t = (src[0] << 16) | (src[1] << 8); 598 dst[0] = base64[(t >> 18) & 0x3f]; 599 dst[1] = base64[(t >> 12) & 0x3f]; 600 dst[2] = base64[(t >> 6) & 0x3f]; 601 dst[3] = '='; 602 dst += 4; 603 r += 4; 604 break; 605 case 1: 606 t = src[0] << 16; 607 dst[0] = base64[(t >> 18) & 0x3f]; 608 dst[1] = base64[(t >> 12) & 0x3f]; 609 dst[2] = dst[3] = '='; 610 dst += 4; 611 r += 4; 612 break; 613 case 0: 614 break; 615 } 616 617 *dst = 0; 618 return (str); 619 } 620 621 /* 622 * Encode username and password 623 */ 624 static int 625 http_basic_auth(conn_t *conn, const char *hdr, const char *usr, const char *pwd) 626 { 627 char *upw, *auth; 628 int r; 629 630 DEBUG(fprintf(stderr, "usr: [%s]\n", usr)); 631 DEBUG(fprintf(stderr, "pwd: [%s]\n", pwd)); 632 if (asprintf(&upw, "%s:%s", usr, pwd) == -1) 633 return (-1); 634 auth = http_base64(upw); 635 free(upw); 636 if (auth == NULL) 637 return (-1); 638 r = http_cmd(conn, "%s: Basic %s", hdr, auth); 639 free(auth); 640 return (r); 641 } 642 643 /* 644 * Send an authorization header 645 */ 646 static int 647 http_authorize(conn_t *conn, const char *hdr, const char *p) 648 { 649 /* basic authorization */ 650 if (strncasecmp(p, "basic:", 6) == 0) { 651 char *user, *pwd, *str; 652 int r; 653 654 /* skip realm */ 655 for (p += 6; *p && *p != ':'; ++p) 656 /* nothing */ ; 657 if (!*p || strchr(++p, ':') == NULL) 658 return (-1); 659 if ((str = strdup(p)) == NULL) 660 return (-1); /* XXX */ 661 user = str; 662 pwd = strchr(str, ':'); 663 *pwd++ = '\0'; 664 r = http_basic_auth(conn, hdr, user, pwd); 665 free(str); 666 return (r); 667 } 668 return (-1); 669 } 670 671 672 /***************************************************************************** 673 * Helper functions for connecting to a server or proxy 674 */ 675 676 /* 677 * Connect to the correct HTTP server or proxy. 678 */ 679 static conn_t * 680 http_connect(struct url *URL, struct url *purl, const char *flags) 681 { 682 conn_t *conn; 683 int verbose; 684 int af, val; 685 686 #ifdef INET6 687 af = AF_UNSPEC; 688 #else 689 af = AF_INET; 690 #endif 691 692 verbose = CHECK_FLAG('v'); 693 if (CHECK_FLAG('4')) 694 af = AF_INET; 695 #ifdef INET6 696 else if (CHECK_FLAG('6')) 697 af = AF_INET6; 698 #endif 699 700 if (purl && strcasecmp(URL->scheme, SCHEME_HTTPS) != 0) { 701 URL = purl; 702 } else if (strcasecmp(URL->scheme, SCHEME_FTP) == 0) { 703 /* can't talk http to an ftp server */ 704 /* XXX should set an error code */ 705 return (NULL); 706 } 707 708 if ((conn = fetch_connect(URL->host, URL->port, af, verbose)) == NULL) 709 /* fetch_connect() has already set an error code */ 710 return (NULL); 711 if (strcasecmp(URL->scheme, SCHEME_HTTPS) == 0 && 712 fetch_ssl(conn, verbose) == -1) { 713 fetch_close(conn); 714 /* grrr */ 715 errno = EAUTH; 716 fetch_syserr(); 717 return (NULL); 718 } 719 720 val = 1; 721 setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, sizeof(val)); 722 723 return (conn); 724 } 725 726 static struct url * 727 http_get_proxy(struct url * url, const char *flags) 728 { 729 struct url *purl; 730 char *p; 731 732 if (flags != NULL && strchr(flags, 'd') != NULL) 733 return (NULL); 734 if (fetch_no_proxy_match(url->host)) 735 return (NULL); 736 if (((p = getenv("HTTP_PROXY")) || (p = getenv("http_proxy"))) && 737 *p && (purl = fetchParseURL(p))) { 738 if (!*purl->scheme) 739 strcpy(purl->scheme, SCHEME_HTTP); 740 if (!purl->port) 741 purl->port = fetch_default_proxy_port(purl->scheme); 742 if (strcasecmp(purl->scheme, SCHEME_HTTP) == 0) 743 return (purl); 744 fetchFreeURL(purl); 745 } 746 return (NULL); 747 } 748 749 static void 750 http_print_html(FILE *out, FILE *in) 751 { 752 size_t len; 753 char *line, *p, *q; 754 int comment, tag; 755 756 comment = tag = 0; 757 while ((line = fgetln(in, &len)) != NULL) { 758 while (len && isspace((unsigned char)line[len - 1])) 759 --len; 760 for (p = q = line; q < line + len; ++q) { 761 if (comment && *q == '-') { 762 if (q + 2 < line + len && 763 strcmp(q, "-->") == 0) { 764 tag = comment = 0; 765 q += 2; 766 } 767 } else if (tag && !comment && *q == '>') { 768 p = q + 1; 769 tag = 0; 770 } else if (!tag && *q == '<') { 771 if (q > p) 772 fwrite(p, q - p, 1, out); 773 tag = 1; 774 if (q + 3 < line + len && 775 strcmp(q, "<!--") == 0) { 776 comment = 1; 777 q += 3; 778 } 779 } 780 } 781 if (!tag && q > p) 782 fwrite(p, q - p, 1, out); 783 fputc('\n', out); 784 } 785 } 786 787 788 /***************************************************************************** 789 * Core 790 */ 791 792 /* 793 * Send a request and process the reply 794 * 795 * XXX This function is way too long, the do..while loop should be split 796 * XXX off into a separate function. 797 */ 798 FILE * 799 http_request(struct url *URL, const char *op, struct url_stat *us, 800 struct url *purl, const char *flags) 801 { 802 char timebuf[80]; 803 char hbuf[MAXHOSTNAMELEN + 7], *host; 804 conn_t *conn; 805 struct url *url, *new; 806 int chunked, direct, ims, need_auth, noredirect, verbose; 807 int e, i, n, val; 808 off_t offset, clength, length, size; 809 time_t mtime; 810 const char *p; 811 FILE *f; 812 hdr_t h; 813 struct tm *timestruct; 814 815 direct = CHECK_FLAG('d'); 816 noredirect = CHECK_FLAG('A'); 817 verbose = CHECK_FLAG('v'); 818 ims = CHECK_FLAG('i'); 819 820 if (direct && purl) { 821 fetchFreeURL(purl); 822 purl = NULL; 823 } 824 825 /* try the provided URL first */ 826 url = URL; 827 828 /* if the A flag is set, we only get one try */ 829 n = noredirect ? 1 : MAX_REDIRECT; 830 i = 0; 831 832 e = HTTP_PROTOCOL_ERROR; 833 need_auth = 0; 834 do { 835 new = NULL; 836 chunked = 0; 837 offset = 0; 838 clength = -1; 839 length = -1; 840 size = -1; 841 mtime = 0; 842 843 /* check port */ 844 if (!url->port) 845 url->port = fetch_default_port(url->scheme); 846 847 /* were we redirected to an FTP URL? */ 848 if (purl == NULL && strcmp(url->scheme, SCHEME_FTP) == 0) { 849 if (strcmp(op, "GET") == 0) 850 return (ftp_request(url, "RETR", us, purl, flags)); 851 else if (strcmp(op, "HEAD") == 0) 852 return (ftp_request(url, "STAT", us, purl, flags)); 853 } 854 855 /* connect to server or proxy */ 856 if ((conn = http_connect(url, purl, flags)) == NULL) 857 goto ouch; 858 859 host = url->host; 860 #ifdef INET6 861 if (strchr(url->host, ':')) { 862 snprintf(hbuf, sizeof(hbuf), "[%s]", url->host); 863 host = hbuf; 864 } 865 #endif 866 if (url->port != fetch_default_port(url->scheme)) { 867 if (host != hbuf) { 868 strcpy(hbuf, host); 869 host = hbuf; 870 } 871 snprintf(hbuf + strlen(hbuf), 872 sizeof(hbuf) - strlen(hbuf), ":%d", url->port); 873 } 874 875 /* send request */ 876 if (verbose) 877 fetch_info("requesting %s://%s%s", 878 url->scheme, host, url->doc); 879 if (purl) { 880 http_cmd(conn, "%s %s://%s%s HTTP/1.1", 881 op, url->scheme, host, url->doc); 882 } else { 883 http_cmd(conn, "%s %s HTTP/1.1", 884 op, url->doc); 885 } 886 887 if (ims && url->ims_time) { 888 timestruct = gmtime((time_t *)&url->ims_time); 889 (void)strftime(timebuf, 80, "%a, %d %b %Y %T GMT", 890 timestruct); 891 if (verbose) 892 fetch_info("If-Modified-Since: %s", timebuf); 893 http_cmd(conn, "If-Modified-Since: %s", timebuf); 894 } 895 /* virtual host */ 896 http_cmd(conn, "Host: %s", host); 897 898 /* proxy authorization */ 899 if (purl) { 900 if (*purl->user || *purl->pwd) 901 http_basic_auth(conn, "Proxy-Authorization", 902 purl->user, purl->pwd); 903 else if ((p = getenv("HTTP_PROXY_AUTH")) != NULL && *p != '\0') 904 http_authorize(conn, "Proxy-Authorization", p); 905 } 906 907 /* server authorization */ 908 if (need_auth || *url->user || *url->pwd) { 909 if (*url->user || *url->pwd) 910 http_basic_auth(conn, "Authorization", url->user, url->pwd); 911 else if ((p = getenv("HTTP_AUTH")) != NULL && *p != '\0') 912 http_authorize(conn, "Authorization", p); 913 else if (fetchAuthMethod && fetchAuthMethod(url) == 0) { 914 http_basic_auth(conn, "Authorization", url->user, url->pwd); 915 } else { 916 http_seterr(HTTP_NEED_AUTH); 917 goto ouch; 918 } 919 } 920 921 /* other headers */ 922 if ((p = getenv("HTTP_REFERER")) != NULL && *p != '\0') { 923 if (strcasecmp(p, "auto") == 0) 924 http_cmd(conn, "Referer: %s://%s%s", 925 url->scheme, host, url->doc); 926 else 927 http_cmd(conn, "Referer: %s", p); 928 } 929 if ((p = getenv("HTTP_USER_AGENT")) != NULL && *p != '\0') 930 http_cmd(conn, "User-Agent: %s", p); 931 else 932 http_cmd(conn, "User-Agent: %s " _LIBFETCH_VER, getprogname()); 933 if (url->offset > 0) 934 http_cmd(conn, "Range: bytes=%lld-", (long long)url->offset); 935 http_cmd(conn, "Connection: close"); 936 http_cmd(conn, ""); 937 938 /* 939 * Force the queued request to be dispatched. Normally, one 940 * would do this with shutdown(2) but squid proxies can be 941 * configured to disallow such half-closed connections. To 942 * be compatible with such configurations, fiddle with socket 943 * options to force the pending data to be written. 944 */ 945 val = 0; 946 setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, 947 sizeof(val)); 948 val = 1; 949 setsockopt(conn->sd, IPPROTO_TCP, TCP_NODELAY, &val, 950 sizeof(val)); 951 952 /* get reply */ 953 switch (http_get_reply(conn)) { 954 case HTTP_OK: 955 case HTTP_PARTIAL: 956 case HTTP_NOT_MODIFIED: 957 /* fine */ 958 break; 959 case HTTP_MOVED_PERM: 960 case HTTP_MOVED_TEMP: 961 case HTTP_SEE_OTHER: 962 /* 963 * Not so fine, but we still have to read the 964 * headers to get the new location. 965 */ 966 break; 967 case HTTP_NEED_AUTH: 968 if (need_auth) { 969 /* 970 * We already sent out authorization code, 971 * so there's nothing more we can do. 972 */ 973 http_seterr(conn->err); 974 goto ouch; 975 } 976 /* try again, but send the password this time */ 977 if (verbose) 978 fetch_info("server requires authorization"); 979 break; 980 case HTTP_NEED_PROXY_AUTH: 981 /* 982 * If we're talking to a proxy, we already sent 983 * our proxy authorization code, so there's 984 * nothing more we can do. 985 */ 986 http_seterr(conn->err); 987 goto ouch; 988 case HTTP_BAD_RANGE: 989 /* 990 * This can happen if we ask for 0 bytes because 991 * we already have the whole file. Consider this 992 * a success for now, and check sizes later. 993 */ 994 break; 995 case HTTP_PROTOCOL_ERROR: 996 /* fall through */ 997 case -1: 998 fetch_syserr(); 999 goto ouch; 1000 default: 1001 http_seterr(conn->err); 1002 if (!verbose) 1003 goto ouch; 1004 /* fall through so we can get the full error message */ 1005 } 1006 1007 /* get headers */ 1008 do { 1009 switch ((h = http_next_header(conn, &p))) { 1010 case hdr_syserror: 1011 fetch_syserr(); 1012 goto ouch; 1013 case hdr_error: 1014 http_seterr(HTTP_PROTOCOL_ERROR); 1015 goto ouch; 1016 case hdr_content_length: 1017 http_parse_length(p, &clength); 1018 break; 1019 case hdr_content_range: 1020 http_parse_range(p, &offset, &length, &size); 1021 break; 1022 case hdr_last_modified: 1023 http_parse_mtime(p, &mtime); 1024 break; 1025 case hdr_location: 1026 if (!HTTP_REDIRECT(conn->err)) 1027 break; 1028 if (new) 1029 free(new); 1030 if (verbose) 1031 fetch_info("%d redirect to %s", conn->err, p); 1032 if (*p == '/') 1033 /* absolute path */ 1034 new = fetchMakeURL(url->scheme, url->host, url->port, p, 1035 url->user, url->pwd); 1036 else 1037 new = fetchParseURL(p); 1038 if (new == NULL) { 1039 /* XXX should set an error code */ 1040 DEBUG(fprintf(stderr, "failed to parse new URL\n")); 1041 goto ouch; 1042 } 1043 if (!*new->user && !*new->pwd) { 1044 strcpy(new->user, url->user); 1045 strcpy(new->pwd, url->pwd); 1046 } 1047 new->offset = url->offset; 1048 new->length = url->length; 1049 break; 1050 case hdr_transfer_encoding: 1051 /* XXX weak test*/ 1052 chunked = (strcasecmp(p, "chunked") == 0); 1053 break; 1054 case hdr_www_authenticate: 1055 if (conn->err != HTTP_NEED_AUTH) 1056 break; 1057 /* if we were smarter, we'd check the method and realm */ 1058 break; 1059 case hdr_end: 1060 /* fall through */ 1061 case hdr_unknown: 1062 /* ignore */ 1063 break; 1064 } 1065 } while (h > hdr_end); 1066 1067 /* we need to provide authentication */ 1068 if (conn->err == HTTP_NEED_AUTH) { 1069 e = conn->err; 1070 need_auth = 1; 1071 fetch_close(conn); 1072 conn = NULL; 1073 continue; 1074 } 1075 1076 /* requested range not satisfiable */ 1077 if (conn->err == HTTP_BAD_RANGE) { 1078 if (url->offset == size && url->length == 0) { 1079 /* asked for 0 bytes; fake it */ 1080 offset = url->offset; 1081 clength = -1; 1082 conn->err = HTTP_OK; 1083 break; 1084 } else { 1085 http_seterr(conn->err); 1086 goto ouch; 1087 } 1088 } 1089 1090 /* we have a hit or an error */ 1091 if (conn->err == HTTP_OK 1092 || conn->err == HTTP_NOT_MODIFIED 1093 || conn->err == HTTP_PARTIAL 1094 || HTTP_ERROR(conn->err)) 1095 break; 1096 1097 /* all other cases: we got a redirect */ 1098 e = conn->err; 1099 need_auth = 0; 1100 fetch_close(conn); 1101 conn = NULL; 1102 if (!new) { 1103 DEBUG(fprintf(stderr, "redirect with no new location\n")); 1104 break; 1105 } 1106 if (url != URL) 1107 fetchFreeURL(url); 1108 url = new; 1109 } while (++i < n); 1110 1111 /* we failed, or ran out of retries */ 1112 if (conn == NULL) { 1113 http_seterr(e); 1114 goto ouch; 1115 } 1116 1117 DEBUG(fprintf(stderr, "offset %lld, length %lld," 1118 " size %lld, clength %lld\n", 1119 (long long)offset, (long long)length, 1120 (long long)size, (long long)clength)); 1121 1122 if (conn->err == HTTP_NOT_MODIFIED) { 1123 http_seterr(HTTP_NOT_MODIFIED); 1124 return (NULL); 1125 } 1126 1127 /* check for inconsistencies */ 1128 if (clength != -1 && length != -1 && clength != length) { 1129 http_seterr(HTTP_PROTOCOL_ERROR); 1130 goto ouch; 1131 } 1132 if (clength == -1) 1133 clength = length; 1134 if (clength != -1) 1135 length = offset + clength; 1136 if (length != -1 && size != -1 && length != size) { 1137 http_seterr(HTTP_PROTOCOL_ERROR); 1138 goto ouch; 1139 } 1140 if (size == -1) 1141 size = length; 1142 1143 /* fill in stats */ 1144 if (us) { 1145 us->size = size; 1146 us->atime = us->mtime = mtime; 1147 } 1148 1149 /* too far? */ 1150 if (URL->offset > 0 && offset > URL->offset) { 1151 http_seterr(HTTP_PROTOCOL_ERROR); 1152 goto ouch; 1153 } 1154 1155 /* report back real offset and size */ 1156 URL->offset = offset; 1157 URL->length = clength; 1158 1159 /* wrap it up in a FILE */ 1160 if ((f = http_funopen(conn, chunked)) == NULL) { 1161 fetch_syserr(); 1162 goto ouch; 1163 } 1164 1165 if (url != URL) 1166 fetchFreeURL(url); 1167 if (purl) 1168 fetchFreeURL(purl); 1169 1170 if (HTTP_ERROR(conn->err)) { 1171 http_print_html(stderr, f); 1172 fclose(f); 1173 f = NULL; 1174 } 1175 1176 return (f); 1177 1178 ouch: 1179 if (url != URL) 1180 fetchFreeURL(url); 1181 if (purl) 1182 fetchFreeURL(purl); 1183 if (conn != NULL) 1184 fetch_close(conn); 1185 return (NULL); 1186 } 1187 1188 1189 /***************************************************************************** 1190 * Entry points 1191 */ 1192 1193 /* 1194 * Retrieve and stat a file by HTTP 1195 */ 1196 FILE * 1197 fetchXGetHTTP(struct url *URL, struct url_stat *us, const char *flags) 1198 { 1199 return (http_request(URL, "GET", us, http_get_proxy(URL, flags), flags)); 1200 } 1201 1202 /* 1203 * Retrieve a file by HTTP 1204 */ 1205 FILE * 1206 fetchGetHTTP(struct url *URL, const char *flags) 1207 { 1208 return (fetchXGetHTTP(URL, NULL, flags)); 1209 } 1210 1211 /* 1212 * Store a file by HTTP 1213 */ 1214 FILE * 1215 fetchPutHTTP(struct url *URL __unused, const char *flags __unused) 1216 { 1217 warnx("fetchPutHTTP(): not implemented"); 1218 return (NULL); 1219 } 1220 1221 /* 1222 * Get an HTTP document's metadata 1223 */ 1224 int 1225 fetchStatHTTP(struct url *URL, struct url_stat *us, const char *flags) 1226 { 1227 FILE *f; 1228 1229 f = http_request(URL, "HEAD", us, http_get_proxy(URL, flags), flags); 1230 if (f == NULL) 1231 return (-1); 1232 fclose(f); 1233 return (0); 1234 } 1235 1236 /* 1237 * List a directory 1238 */ 1239 struct url_ent * 1240 fetchListHTTP(struct url *url __unused, const char *flags __unused) 1241 { 1242 warnx("fetchListHTTP(): not implemented"); 1243 return (NULL); 1244 } 1245