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(*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 bcopy(io->buf + io->bufpos, buf + pos, 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 && tolower(*str++) == tolower(*hdr++)) 438 /* nothing */; 439 if (*str || *hdr != ':') 440 return (NULL); 441 while (*hdr && isspace((unsigned char)*++hdr)) 442 /* nothing */; 443 return (hdr); 444 } 445 446 /* 447 * Get the next header and return the appropriate symbolic code. 448 */ 449 static hdr_t 450 http_next_header(conn_t *conn, const char **p) 451 { 452 int i; 453 454 if (fetch_getln(conn) == -1) 455 return (hdr_syserror); 456 while (conn->buflen && isspace((unsigned char)conn->buf[conn->buflen - 1])) 457 conn->buflen--; 458 conn->buf[conn->buflen] = '\0'; 459 if (conn->buflen == 0) 460 return (hdr_end); 461 /* 462 * We could check for malformed headers but we don't really care. 463 * A valid header starts with a token immediately followed by a 464 * colon; a token is any sequence of non-control, non-whitespace 465 * characters except "()<>@,;:\\\"{}". 466 */ 467 for (i = 0; hdr_names[i].num != hdr_unknown; i++) 468 if ((*p = http_match(hdr_names[i].name, conn->buf)) != NULL) 469 return (hdr_names[i].num); 470 return (hdr_unknown); 471 } 472 473 /* 474 * Parse a last-modified header 475 */ 476 static int 477 http_parse_mtime(const char *p, time_t *mtime) 478 { 479 char locale[64], *r; 480 struct tm tm; 481 482 strncpy(locale, setlocale(LC_TIME, NULL), sizeof(locale)); 483 setlocale(LC_TIME, "C"); 484 r = strptime(p, "%a, %d %b %Y %H:%M:%S GMT", &tm); 485 /* XXX should add support for date-2 and date-3 */ 486 setlocale(LC_TIME, locale); 487 if (r == NULL) 488 return (-1); 489 DEBUG(fprintf(stderr, "last modified: [%04d-%02d-%02d " 490 "%02d:%02d:%02d]\n", 491 tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, 492 tm.tm_hour, tm.tm_min, tm.tm_sec)); 493 *mtime = timegm(&tm); 494 return (0); 495 } 496 497 /* 498 * Parse a content-length header 499 */ 500 static int 501 http_parse_length(const char *p, off_t *length) 502 { 503 off_t len; 504 505 for (len = 0; *p && isdigit((unsigned char)*p); ++p) 506 len = len * 10 + (*p - '0'); 507 if (*p) 508 return (-1); 509 DEBUG(fprintf(stderr, "content length: [%lld]\n", 510 (long long)len)); 511 *length = len; 512 return (0); 513 } 514 515 /* 516 * Parse a content-range header 517 */ 518 static int 519 http_parse_range(const char *p, off_t *offset, off_t *length, off_t *size) 520 { 521 off_t first, last, len; 522 523 if (strncasecmp(p, "bytes ", 6) != 0) 524 return (-1); 525 p += 6; 526 if (*p == '*') { 527 first = last = -1; 528 ++p; 529 } else { 530 for (first = 0; *p && isdigit((unsigned char)*p); ++p) 531 first = first * 10 + *p - '0'; 532 if (*p != '-') 533 return (-1); 534 for (last = 0, ++p; *p && isdigit((unsigned char)*p); ++p) 535 last = last * 10 + *p - '0'; 536 } 537 if (first > last || *p != '/') 538 return (-1); 539 for (len = 0, ++p; *p && isdigit((unsigned char)*p); ++p) 540 len = len * 10 + *p - '0'; 541 if (*p || len < last - first + 1) 542 return (-1); 543 if (first == -1) { 544 DEBUG(fprintf(stderr, "content range: [*/%lld]\n", 545 (long long)len)); 546 *length = 0; 547 } else { 548 DEBUG(fprintf(stderr, "content range: [%lld-%lld/%lld]\n", 549 (long long)first, (long long)last, (long long)len)); 550 *length = last - first + 1; 551 } 552 *offset = first; 553 *size = len; 554 return (0); 555 } 556 557 558 /***************************************************************************** 559 * Helper functions for authorization 560 */ 561 562 /* 563 * Base64 encoding 564 */ 565 static char * 566 http_base64(const char *src) 567 { 568 static const char base64[] = 569 "ABCDEFGHIJKLMNOPQRSTUVWXYZ" 570 "abcdefghijklmnopqrstuvwxyz" 571 "0123456789+/"; 572 char *str, *dst; 573 size_t l; 574 int t, r; 575 576 l = strlen(src); 577 if ((str = malloc(((l + 2) / 3) * 4 + 1)) == NULL) 578 return (NULL); 579 dst = str; 580 r = 0; 581 582 while (l >= 3) { 583 t = (src[0] << 16) | (src[1] << 8) | src[2]; 584 dst[0] = base64[(t >> 18) & 0x3f]; 585 dst[1] = base64[(t >> 12) & 0x3f]; 586 dst[2] = base64[(t >> 6) & 0x3f]; 587 dst[3] = base64[(t >> 0) & 0x3f]; 588 src += 3; l -= 3; 589 dst += 4; r += 4; 590 } 591 592 switch (l) { 593 case 2: 594 t = (src[0] << 16) | (src[1] << 8); 595 dst[0] = base64[(t >> 18) & 0x3f]; 596 dst[1] = base64[(t >> 12) & 0x3f]; 597 dst[2] = base64[(t >> 6) & 0x3f]; 598 dst[3] = '='; 599 dst += 4; 600 r += 4; 601 break; 602 case 1: 603 t = src[0] << 16; 604 dst[0] = base64[(t >> 18) & 0x3f]; 605 dst[1] = base64[(t >> 12) & 0x3f]; 606 dst[2] = dst[3] = '='; 607 dst += 4; 608 r += 4; 609 break; 610 case 0: 611 break; 612 } 613 614 *dst = 0; 615 return (str); 616 } 617 618 /* 619 * Encode username and password 620 */ 621 static int 622 http_basic_auth(conn_t *conn, const char *hdr, const char *usr, const char *pwd) 623 { 624 char *upw, *auth; 625 int r; 626 627 DEBUG(fprintf(stderr, "usr: [%s]\n", usr)); 628 DEBUG(fprintf(stderr, "pwd: [%s]\n", pwd)); 629 if (asprintf(&upw, "%s:%s", usr, pwd) == -1) 630 return (-1); 631 auth = http_base64(upw); 632 free(upw); 633 if (auth == NULL) 634 return (-1); 635 r = http_cmd(conn, "%s: Basic %s", hdr, auth); 636 free(auth); 637 return (r); 638 } 639 640 /* 641 * Send an authorization header 642 */ 643 static int 644 http_authorize(conn_t *conn, const char *hdr, const char *p) 645 { 646 /* basic authorization */ 647 if (strncasecmp(p, "basic:", 6) == 0) { 648 char *user, *pwd, *str; 649 int r; 650 651 /* skip realm */ 652 for (p += 6; *p && *p != ':'; ++p) 653 /* nothing */ ; 654 if (!*p || strchr(++p, ':') == NULL) 655 return (-1); 656 if ((str = strdup(p)) == NULL) 657 return (-1); /* XXX */ 658 user = str; 659 pwd = strchr(str, ':'); 660 *pwd++ = '\0'; 661 r = http_basic_auth(conn, hdr, user, pwd); 662 free(str); 663 return (r); 664 } 665 return (-1); 666 } 667 668 669 /***************************************************************************** 670 * Helper functions for connecting to a server or proxy 671 */ 672 673 /* 674 * Connect to the correct HTTP server or proxy. 675 */ 676 static conn_t * 677 http_connect(struct url *URL, struct url *purl, const char *flags) 678 { 679 conn_t *conn; 680 int verbose; 681 int af, val; 682 683 #ifdef INET6 684 af = AF_UNSPEC; 685 #else 686 af = AF_INET; 687 #endif 688 689 verbose = CHECK_FLAG('v'); 690 if (CHECK_FLAG('4')) 691 af = AF_INET; 692 #ifdef INET6 693 else if (CHECK_FLAG('6')) 694 af = AF_INET6; 695 #endif 696 697 if (purl && strcasecmp(URL->scheme, SCHEME_HTTPS) != 0) { 698 URL = purl; 699 } else if (strcasecmp(URL->scheme, SCHEME_FTP) == 0) { 700 /* can't talk http to an ftp server */ 701 /* XXX should set an error code */ 702 return (NULL); 703 } 704 705 if ((conn = fetch_connect(URL->host, URL->port, af, verbose)) == NULL) 706 /* fetch_connect() has already set an error code */ 707 return (NULL); 708 if (strcasecmp(URL->scheme, SCHEME_HTTPS) == 0 && 709 fetch_ssl(conn, verbose) == -1) { 710 fetch_close(conn); 711 /* grrr */ 712 errno = EAUTH; 713 fetch_syserr(); 714 return (NULL); 715 } 716 717 val = 1; 718 setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, sizeof(val)); 719 720 return (conn); 721 } 722 723 static struct url * 724 http_get_proxy(struct url * url, const char *flags) 725 { 726 struct url *purl; 727 char *p; 728 729 if (flags != NULL && strchr(flags, 'd') != NULL) 730 return (NULL); 731 if (fetch_no_proxy_match(url->host)) 732 return (NULL); 733 if (((p = getenv("HTTP_PROXY")) || (p = getenv("http_proxy"))) && 734 *p && (purl = fetchParseURL(p))) { 735 if (!*purl->scheme) 736 strcpy(purl->scheme, SCHEME_HTTP); 737 if (!purl->port) 738 purl->port = fetch_default_proxy_port(purl->scheme); 739 if (strcasecmp(purl->scheme, SCHEME_HTTP) == 0) 740 return (purl); 741 fetchFreeURL(purl); 742 } 743 return (NULL); 744 } 745 746 static void 747 http_print_html(FILE *out, FILE *in) 748 { 749 size_t len; 750 char *line, *p, *q; 751 int comment, tag; 752 753 comment = tag = 0; 754 while ((line = fgetln(in, &len)) != NULL) { 755 while (len && isspace((unsigned char)line[len - 1])) 756 --len; 757 for (p = q = line; q < line + len; ++q) { 758 if (comment && *q == '-') { 759 if (q + 2 < line + len && 760 strcmp(q, "-->") == 0) { 761 tag = comment = 0; 762 q += 2; 763 } 764 } else if (tag && !comment && *q == '>') { 765 p = q + 1; 766 tag = 0; 767 } else if (!tag && *q == '<') { 768 if (q > p) 769 fwrite(p, q - p, 1, out); 770 tag = 1; 771 if (q + 3 < line + len && 772 strcmp(q, "<!--") == 0) { 773 comment = 1; 774 q += 3; 775 } 776 } 777 } 778 if (!tag && q > p) 779 fwrite(p, q - p, 1, out); 780 fputc('\n', out); 781 } 782 } 783 784 785 /***************************************************************************** 786 * Core 787 */ 788 789 /* 790 * Send a request and process the reply 791 * 792 * XXX This function is way too long, the do..while loop should be split 793 * XXX off into a separate function. 794 */ 795 FILE * 796 http_request(struct url *URL, const char *op, struct url_stat *us, 797 struct url *purl, const char *flags) 798 { 799 conn_t *conn; 800 struct url *url, *new; 801 int chunked, direct, need_auth, noredirect, verbose; 802 int e, i, n, val; 803 off_t offset, clength, length, size; 804 time_t mtime; 805 const char *p; 806 FILE *f; 807 hdr_t h; 808 char hbuf[MAXHOSTNAMELEN + 7], *host; 809 810 direct = CHECK_FLAG('d'); 811 noredirect = CHECK_FLAG('A'); 812 verbose = CHECK_FLAG('v'); 813 814 if (direct && purl) { 815 fetchFreeURL(purl); 816 purl = NULL; 817 } 818 819 /* try the provided URL first */ 820 url = URL; 821 822 /* if the A flag is set, we only get one try */ 823 n = noredirect ? 1 : MAX_REDIRECT; 824 i = 0; 825 826 e = HTTP_PROTOCOL_ERROR; 827 need_auth = 0; 828 do { 829 new = NULL; 830 chunked = 0; 831 offset = 0; 832 clength = -1; 833 length = -1; 834 size = -1; 835 mtime = 0; 836 837 /* check port */ 838 if (!url->port) 839 url->port = fetch_default_port(url->scheme); 840 841 /* were we redirected to an FTP URL? */ 842 if (purl == NULL && strcmp(url->scheme, SCHEME_FTP) == 0) { 843 if (strcmp(op, "GET") == 0) 844 return (ftp_request(url, "RETR", us, purl, flags)); 845 else if (strcmp(op, "HEAD") == 0) 846 return (ftp_request(url, "STAT", us, purl, flags)); 847 } 848 849 /* connect to server or proxy */ 850 if ((conn = http_connect(url, purl, flags)) == NULL) 851 goto ouch; 852 853 host = url->host; 854 #ifdef INET6 855 if (strchr(url->host, ':')) { 856 snprintf(hbuf, sizeof(hbuf), "[%s]", url->host); 857 host = hbuf; 858 } 859 #endif 860 if (url->port != fetch_default_port(url->scheme)) { 861 if (host != hbuf) { 862 strcpy(hbuf, host); 863 host = hbuf; 864 } 865 snprintf(hbuf + strlen(hbuf), 866 sizeof(hbuf) - strlen(hbuf), ":%d", url->port); 867 } 868 869 /* send request */ 870 if (verbose) 871 fetch_info("requesting %s://%s%s", 872 url->scheme, host, url->doc); 873 if (purl) { 874 http_cmd(conn, "%s %s://%s%s HTTP/1.1", 875 op, url->scheme, host, url->doc); 876 } else { 877 http_cmd(conn, "%s %s HTTP/1.1", 878 op, url->doc); 879 } 880 881 /* virtual host */ 882 http_cmd(conn, "Host: %s", host); 883 884 /* proxy authorization */ 885 if (purl) { 886 if (*purl->user || *purl->pwd) 887 http_basic_auth(conn, "Proxy-Authorization", 888 purl->user, purl->pwd); 889 else if ((p = getenv("HTTP_PROXY_AUTH")) != NULL && *p != '\0') 890 http_authorize(conn, "Proxy-Authorization", p); 891 } 892 893 /* server authorization */ 894 if (need_auth || *url->user || *url->pwd) { 895 if (*url->user || *url->pwd) 896 http_basic_auth(conn, "Authorization", url->user, url->pwd); 897 else if ((p = getenv("HTTP_AUTH")) != NULL && *p != '\0') 898 http_authorize(conn, "Authorization", p); 899 else if (fetchAuthMethod && fetchAuthMethod(url) == 0) { 900 http_basic_auth(conn, "Authorization", url->user, url->pwd); 901 } else { 902 http_seterr(HTTP_NEED_AUTH); 903 goto ouch; 904 } 905 } 906 907 /* other headers */ 908 if ((p = getenv("HTTP_REFERER")) != NULL && *p != '\0') { 909 if (strcasecmp(p, "auto") == 0) 910 http_cmd(conn, "Referer: %s://%s%s", 911 url->scheme, host, url->doc); 912 else 913 http_cmd(conn, "Referer: %s", p); 914 } 915 if ((p = getenv("HTTP_USER_AGENT")) != NULL && *p != '\0') 916 http_cmd(conn, "User-Agent: %s", p); 917 else 918 http_cmd(conn, "User-Agent: %s " _LIBFETCH_VER, getprogname()); 919 if (url->offset > 0) 920 http_cmd(conn, "Range: bytes=%lld-", (long long)url->offset); 921 http_cmd(conn, "Connection: close"); 922 http_cmd(conn, ""); 923 924 /* 925 * Force the queued request to be dispatched. Normally, one 926 * would do this with shutdown(2) but squid proxies can be 927 * configured to disallow such half-closed connections. To 928 * be compatible with such configurations, fiddle with socket 929 * options to force the pending data to be written. 930 */ 931 val = 0; 932 setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, 933 sizeof(val)); 934 val = 1; 935 setsockopt(conn->sd, IPPROTO_TCP, TCP_NODELAY, &val, 936 sizeof(val)); 937 938 /* get reply */ 939 switch (http_get_reply(conn)) { 940 case HTTP_OK: 941 case HTTP_PARTIAL: 942 /* fine */ 943 break; 944 case HTTP_MOVED_PERM: 945 case HTTP_MOVED_TEMP: 946 case HTTP_SEE_OTHER: 947 /* 948 * Not so fine, but we still have to read the 949 * headers to get the new location. 950 */ 951 break; 952 case HTTP_NEED_AUTH: 953 if (need_auth) { 954 /* 955 * We already sent out authorization code, 956 * so there's nothing more we can do. 957 */ 958 http_seterr(conn->err); 959 goto ouch; 960 } 961 /* try again, but send the password this time */ 962 if (verbose) 963 fetch_info("server requires authorization"); 964 break; 965 case HTTP_NEED_PROXY_AUTH: 966 /* 967 * If we're talking to a proxy, we already sent 968 * our proxy authorization code, so there's 969 * nothing more we can do. 970 */ 971 http_seterr(conn->err); 972 goto ouch; 973 case HTTP_BAD_RANGE: 974 /* 975 * This can happen if we ask for 0 bytes because 976 * we already have the whole file. Consider this 977 * a success for now, and check sizes later. 978 */ 979 break; 980 case HTTP_PROTOCOL_ERROR: 981 /* fall through */ 982 case -1: 983 fetch_syserr(); 984 goto ouch; 985 default: 986 http_seterr(conn->err); 987 if (!verbose) 988 goto ouch; 989 /* fall through so we can get the full error message */ 990 } 991 992 /* get headers */ 993 do { 994 switch ((h = http_next_header(conn, &p))) { 995 case hdr_syserror: 996 fetch_syserr(); 997 goto ouch; 998 case hdr_error: 999 http_seterr(HTTP_PROTOCOL_ERROR); 1000 goto ouch; 1001 case hdr_content_length: 1002 http_parse_length(p, &clength); 1003 break; 1004 case hdr_content_range: 1005 http_parse_range(p, &offset, &length, &size); 1006 break; 1007 case hdr_last_modified: 1008 http_parse_mtime(p, &mtime); 1009 break; 1010 case hdr_location: 1011 if (!HTTP_REDIRECT(conn->err)) 1012 break; 1013 if (new) 1014 free(new); 1015 if (verbose) 1016 fetch_info("%d redirect to %s", conn->err, p); 1017 if (*p == '/') 1018 /* absolute path */ 1019 new = fetchMakeURL(url->scheme, url->host, url->port, p, 1020 url->user, url->pwd); 1021 else 1022 new = fetchParseURL(p); 1023 if (new == NULL) { 1024 /* XXX should set an error code */ 1025 DEBUG(fprintf(stderr, "failed to parse new URL\n")); 1026 goto ouch; 1027 } 1028 if (!*new->user && !*new->pwd) { 1029 strcpy(new->user, url->user); 1030 strcpy(new->pwd, url->pwd); 1031 } 1032 new->offset = url->offset; 1033 new->length = url->length; 1034 break; 1035 case hdr_transfer_encoding: 1036 /* XXX weak test*/ 1037 chunked = (strcasecmp(p, "chunked") == 0); 1038 break; 1039 case hdr_www_authenticate: 1040 if (conn->err != HTTP_NEED_AUTH) 1041 break; 1042 /* if we were smarter, we'd check the method and realm */ 1043 break; 1044 case hdr_end: 1045 /* fall through */ 1046 case hdr_unknown: 1047 /* ignore */ 1048 break; 1049 } 1050 } while (h > hdr_end); 1051 1052 /* we need to provide authentication */ 1053 if (conn->err == HTTP_NEED_AUTH) { 1054 e = conn->err; 1055 need_auth = 1; 1056 fetch_close(conn); 1057 conn = NULL; 1058 continue; 1059 } 1060 1061 /* requested range not satisfiable */ 1062 if (conn->err == HTTP_BAD_RANGE) { 1063 if (url->offset == size && url->length == 0) { 1064 /* asked for 0 bytes; fake it */ 1065 offset = url->offset; 1066 conn->err = HTTP_OK; 1067 break; 1068 } else { 1069 http_seterr(conn->err); 1070 goto ouch; 1071 } 1072 } 1073 1074 /* we have a hit or an error */ 1075 if (conn->err == HTTP_OK || conn->err == HTTP_PARTIAL || HTTP_ERROR(conn->err)) 1076 break; 1077 1078 /* all other cases: we got a redirect */ 1079 e = conn->err; 1080 need_auth = 0; 1081 fetch_close(conn); 1082 conn = NULL; 1083 if (!new) { 1084 DEBUG(fprintf(stderr, "redirect with no new location\n")); 1085 break; 1086 } 1087 if (url != URL) 1088 fetchFreeURL(url); 1089 url = new; 1090 } while (++i < n); 1091 1092 /* we failed, or ran out of retries */ 1093 if (conn == NULL) { 1094 http_seterr(e); 1095 goto ouch; 1096 } 1097 1098 DEBUG(fprintf(stderr, "offset %lld, length %lld," 1099 " size %lld, clength %lld\n", 1100 (long long)offset, (long long)length, 1101 (long long)size, (long long)clength)); 1102 1103 /* check for inconsistencies */ 1104 if (clength != -1 && length != -1 && clength != length) { 1105 http_seterr(HTTP_PROTOCOL_ERROR); 1106 goto ouch; 1107 } 1108 if (clength == -1) 1109 clength = length; 1110 if (clength != -1) 1111 length = offset + clength; 1112 if (length != -1 && size != -1 && length != size) { 1113 http_seterr(HTTP_PROTOCOL_ERROR); 1114 goto ouch; 1115 } 1116 if (size == -1) 1117 size = length; 1118 1119 /* fill in stats */ 1120 if (us) { 1121 us->size = size; 1122 us->atime = us->mtime = mtime; 1123 } 1124 1125 /* too far? */ 1126 if (URL->offset > 0 && offset > URL->offset) { 1127 http_seterr(HTTP_PROTOCOL_ERROR); 1128 goto ouch; 1129 } 1130 1131 /* report back real offset and size */ 1132 URL->offset = offset; 1133 URL->length = clength; 1134 1135 /* wrap it up in a FILE */ 1136 if ((f = http_funopen(conn, chunked)) == NULL) { 1137 fetch_syserr(); 1138 goto ouch; 1139 } 1140 1141 if (url != URL) 1142 fetchFreeURL(url); 1143 if (purl) 1144 fetchFreeURL(purl); 1145 1146 if (HTTP_ERROR(conn->err)) { 1147 http_print_html(stderr, f); 1148 fclose(f); 1149 f = NULL; 1150 } 1151 1152 return (f); 1153 1154 ouch: 1155 if (url != URL) 1156 fetchFreeURL(url); 1157 if (purl) 1158 fetchFreeURL(purl); 1159 if (conn != NULL) 1160 fetch_close(conn); 1161 return (NULL); 1162 } 1163 1164 1165 /***************************************************************************** 1166 * Entry points 1167 */ 1168 1169 /* 1170 * Retrieve and stat a file by HTTP 1171 */ 1172 FILE * 1173 fetchXGetHTTP(struct url *URL, struct url_stat *us, const char *flags) 1174 { 1175 return (http_request(URL, "GET", us, http_get_proxy(URL, flags), flags)); 1176 } 1177 1178 /* 1179 * Retrieve a file by HTTP 1180 */ 1181 FILE * 1182 fetchGetHTTP(struct url *URL, const char *flags) 1183 { 1184 return (fetchXGetHTTP(URL, NULL, flags)); 1185 } 1186 1187 /* 1188 * Store a file by HTTP 1189 */ 1190 FILE * 1191 fetchPutHTTP(struct url *URL __unused, const char *flags __unused) 1192 { 1193 warnx("fetchPutHTTP(): not implemented"); 1194 return (NULL); 1195 } 1196 1197 /* 1198 * Get an HTTP document's metadata 1199 */ 1200 int 1201 fetchStatHTTP(struct url *URL, struct url_stat *us, const char *flags) 1202 { 1203 FILE *f; 1204 1205 f = http_request(URL, "HEAD", us, http_get_proxy(URL, flags), flags); 1206 if (f == NULL) 1207 return (-1); 1208 fclose(f); 1209 return (0); 1210 } 1211 1212 /* 1213 * List a directory 1214 */ 1215 struct url_ent * 1216 fetchListHTTP(struct url *url __unused, const char *flags __unused) 1217 { 1218 warnx("fetchListHTTP(): not implemented"); 1219 return (NULL); 1220 } 1221