http.c revision 242293
1/*- 2 * Copyright (c) 2000-2011 Dag-Erling 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: stable/9/lib/libfetch/http.c 242293 2012-10-29 04:18:34Z eadler $"); 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#include <md5.h> 80 81#include <netinet/in.h> 82#include <netinet/tcp.h> 83 84#include "fetch.h" 85#include "common.h" 86#include "httperr.h" 87 88/* Maximum number of redirects to follow */ 89#define MAX_REDIRECT 20 90 91/* Symbolic names for reply codes we care about */ 92#define HTTP_OK 200 93#define HTTP_PARTIAL 206 94#define HTTP_MOVED_PERM 301 95#define HTTP_MOVED_TEMP 302 96#define HTTP_SEE_OTHER 303 97#define HTTP_NOT_MODIFIED 304 98#define HTTP_USE_PROXY 305 99#define HTTP_TEMP_REDIRECT 307 100#define HTTP_PERM_REDIRECT 308 101#define HTTP_NEED_AUTH 401 102#define HTTP_NEED_PROXY_AUTH 407 103#define HTTP_BAD_RANGE 416 104#define HTTP_PROTOCOL_ERROR 999 105 106#define HTTP_REDIRECT(xyz) ((xyz) == HTTP_MOVED_PERM \ 107 || (xyz) == HTTP_MOVED_TEMP \ 108 || (xyz) == HTTP_TEMP_REDIRECT \ 109 || (xyz) == HTTP_USE_PROXY \ 110 || (xyz) == HTTP_SEE_OTHER) 111 112#define HTTP_ERROR(xyz) ((xyz) > 400 && (xyz) < 599) 113 114 115/***************************************************************************** 116 * I/O functions for decoding chunked streams 117 */ 118 119struct httpio 120{ 121 conn_t *conn; /* connection */ 122 int chunked; /* chunked mode */ 123 char *buf; /* chunk buffer */ 124 size_t bufsize; /* size of chunk buffer */ 125 ssize_t buflen; /* amount of data currently in buffer */ 126 int bufpos; /* current read offset in buffer */ 127 int eof; /* end-of-file flag */ 128 int error; /* error flag */ 129 size_t chunksize; /* remaining size of current chunk */ 130#ifndef NDEBUG 131 size_t total; 132#endif 133}; 134 135/* 136 * Get next chunk header 137 */ 138static int 139http_new_chunk(struct httpio *io) 140{ 141 char *p; 142 143 if (fetch_getln(io->conn) == -1) 144 return (-1); 145 146 if (io->conn->buflen < 2 || !isxdigit((unsigned char)*io->conn->buf)) 147 return (-1); 148 149 for (p = io->conn->buf; *p && !isspace((unsigned char)*p); ++p) { 150 if (*p == ';') 151 break; 152 if (!isxdigit((unsigned char)*p)) 153 return (-1); 154 if (isdigit((unsigned char)*p)) { 155 io->chunksize = io->chunksize * 16 + 156 *p - '0'; 157 } else { 158 io->chunksize = io->chunksize * 16 + 159 10 + tolower((unsigned char)*p) - 'a'; 160 } 161 } 162 163#ifndef NDEBUG 164 if (fetchDebug) { 165 io->total += io->chunksize; 166 if (io->chunksize == 0) 167 fprintf(stderr, "%s(): end of last chunk\n", __func__); 168 else 169 fprintf(stderr, "%s(): new chunk: %lu (%lu)\n", 170 __func__, (unsigned long)io->chunksize, 171 (unsigned long)io->total); 172 } 173#endif 174 175 return (io->chunksize); 176} 177 178/* 179 * Grow the input buffer to at least len bytes 180 */ 181static inline int 182http_growbuf(struct httpio *io, size_t len) 183{ 184 char *tmp; 185 186 if (io->bufsize >= len) 187 return (0); 188 189 if ((tmp = realloc(io->buf, len)) == NULL) 190 return (-1); 191 io->buf = tmp; 192 io->bufsize = len; 193 return (0); 194} 195 196/* 197 * Fill the input buffer, do chunk decoding on the fly 198 */ 199static int 200http_fillbuf(struct httpio *io, size_t len) 201{ 202 ssize_t nbytes; 203 204 if (io->error) 205 return (-1); 206 if (io->eof) 207 return (0); 208 209 if (io->chunked == 0) { 210 if (http_growbuf(io, len) == -1) 211 return (-1); 212 if ((nbytes = fetch_read(io->conn, io->buf, len)) == -1) { 213 io->error = errno; 214 return (-1); 215 } 216 io->buflen = nbytes; 217 io->bufpos = 0; 218 return (io->buflen); 219 } 220 221 if (io->chunksize == 0) { 222 switch (http_new_chunk(io)) { 223 case -1: 224 io->error = 1; 225 return (-1); 226 case 0: 227 io->eof = 1; 228 return (0); 229 } 230 } 231 232 if (len > io->chunksize) 233 len = io->chunksize; 234 if (http_growbuf(io, len) == -1) 235 return (-1); 236 if ((nbytes = fetch_read(io->conn, io->buf, len)) == -1) { 237 io->error = errno; 238 return (-1); 239 } 240 io->buflen = nbytes; 241 io->chunksize -= io->buflen; 242 243 if (io->chunksize == 0) { 244 char endl[2]; 245 246 if (fetch_read(io->conn, endl, 2) != 2 || 247 endl[0] != '\r' || endl[1] != '\n') 248 return (-1); 249 } 250 251 io->bufpos = 0; 252 253 return (io->buflen); 254} 255 256/* 257 * Read function 258 */ 259static int 260http_readfn(void *v, char *buf, int len) 261{ 262 struct httpio *io = (struct httpio *)v; 263 int l, pos; 264 265 if (io->error) 266 return (-1); 267 if (io->eof) 268 return (0); 269 270 for (pos = 0; len > 0; pos += l, len -= l) { 271 /* empty buffer */ 272 if (!io->buf || io->bufpos == io->buflen) 273 if (http_fillbuf(io, len) < 1) 274 break; 275 l = io->buflen - io->bufpos; 276 if (len < l) 277 l = len; 278 memcpy(buf + pos, io->buf + io->bufpos, l); 279 io->bufpos += l; 280 } 281 282 if (!pos && io->error) { 283 if (io->error == EINTR) 284 io->error = 0; 285 return (-1); 286 } 287 return (pos); 288} 289 290/* 291 * Write function 292 */ 293static int 294http_writefn(void *v, const char *buf, int len) 295{ 296 struct httpio *io = (struct httpio *)v; 297 298 return (fetch_write(io->conn, buf, len)); 299} 300 301/* 302 * Close function 303 */ 304static int 305http_closefn(void *v) 306{ 307 struct httpio *io = (struct httpio *)v; 308 int r; 309 310 r = fetch_close(io->conn); 311 if (io->buf) 312 free(io->buf); 313 free(io); 314 return (r); 315} 316 317/* 318 * Wrap a file descriptor up 319 */ 320static FILE * 321http_funopen(conn_t *conn, int chunked) 322{ 323 struct httpio *io; 324 FILE *f; 325 326 if ((io = calloc(1, sizeof(*io))) == NULL) { 327 fetch_syserr(); 328 return (NULL); 329 } 330 io->conn = conn; 331 io->chunked = chunked; 332 f = funopen(io, http_readfn, http_writefn, NULL, http_closefn); 333 if (f == NULL) { 334 fetch_syserr(); 335 free(io); 336 return (NULL); 337 } 338 return (f); 339} 340 341 342/***************************************************************************** 343 * Helper functions for talking to the server and parsing its replies 344 */ 345 346/* Header types */ 347typedef enum { 348 hdr_syserror = -2, 349 hdr_error = -1, 350 hdr_end = 0, 351 hdr_unknown = 1, 352 hdr_content_length, 353 hdr_content_range, 354 hdr_last_modified, 355 hdr_location, 356 hdr_transfer_encoding, 357 hdr_www_authenticate, 358 hdr_proxy_authenticate, 359} hdr_t; 360 361/* Names of interesting headers */ 362static struct { 363 hdr_t num; 364 const char *name; 365} hdr_names[] = { 366 { hdr_content_length, "Content-Length" }, 367 { hdr_content_range, "Content-Range" }, 368 { hdr_last_modified, "Last-Modified" }, 369 { hdr_location, "Location" }, 370 { hdr_transfer_encoding, "Transfer-Encoding" }, 371 { hdr_www_authenticate, "WWW-Authenticate" }, 372 { hdr_proxy_authenticate, "Proxy-Authenticate" }, 373 { hdr_unknown, NULL }, 374}; 375 376/* 377 * Send a formatted line; optionally echo to terminal 378 */ 379static int 380http_cmd(conn_t *conn, const char *fmt, ...) 381{ 382 va_list ap; 383 size_t len; 384 char *msg; 385 int r; 386 387 va_start(ap, fmt); 388 len = vasprintf(&msg, fmt, ap); 389 va_end(ap); 390 391 if (msg == NULL) { 392 errno = ENOMEM; 393 fetch_syserr(); 394 return (-1); 395 } 396 397 r = fetch_putln(conn, msg, len); 398 free(msg); 399 400 if (r == -1) { 401 fetch_syserr(); 402 return (-1); 403 } 404 405 return (0); 406} 407 408/* 409 * Get and parse status line 410 */ 411static int 412http_get_reply(conn_t *conn) 413{ 414 char *p; 415 416 if (fetch_getln(conn) == -1) 417 return (-1); 418 /* 419 * A valid status line looks like "HTTP/m.n xyz reason" where m 420 * and n are the major and minor protocol version numbers and xyz 421 * is the reply code. 422 * Unfortunately, there are servers out there (NCSA 1.5.1, to name 423 * just one) that do not send a version number, so we can't rely 424 * on finding one, but if we do, insist on it being 1.0 or 1.1. 425 * We don't care about the reason phrase. 426 */ 427 if (strncmp(conn->buf, "HTTP", 4) != 0) 428 return (HTTP_PROTOCOL_ERROR); 429 p = conn->buf + 4; 430 if (*p == '/') { 431 if (p[1] != '1' || p[2] != '.' || (p[3] != '0' && p[3] != '1')) 432 return (HTTP_PROTOCOL_ERROR); 433 p += 4; 434 } 435 if (*p != ' ' || 436 !isdigit((unsigned char)p[1]) || 437 !isdigit((unsigned char)p[2]) || 438 !isdigit((unsigned char)p[3])) 439 return (HTTP_PROTOCOL_ERROR); 440 441 conn->err = (p[1] - '0') * 100 + (p[2] - '0') * 10 + (p[3] - '0'); 442 return (conn->err); 443} 444 445/* 446 * Check a header; if the type matches the given string, return a pointer 447 * to the beginning of the value. 448 */ 449static const char * 450http_match(const char *str, const char *hdr) 451{ 452 while (*str && *hdr && 453 tolower((unsigned char)*str++) == tolower((unsigned char)*hdr++)) 454 /* nothing */; 455 if (*str || *hdr != ':') 456 return (NULL); 457 while (*hdr && isspace((unsigned char)*++hdr)) 458 /* nothing */; 459 return (hdr); 460} 461 462 463/* 464 * Get the next header and return the appropriate symbolic code. We 465 * need to read one line ahead for checking for a continuation line 466 * belonging to the current header (continuation lines start with 467 * white space). 468 * 469 * We get called with a fresh line already in the conn buffer, either 470 * from the previous http_next_header() invocation, or, the first 471 * time, from a fetch_getln() performed by our caller. 472 * 473 * This stops when we encounter an empty line (we dont read beyond the header 474 * area). 475 * 476 * Note that the "headerbuf" is just a place to return the result. Its 477 * contents are not used for the next call. This means that no cleanup 478 * is needed when ie doing another connection, just call the cleanup when 479 * fully done to deallocate memory. 480 */ 481 482/* Limit the max number of continuation lines to some reasonable value */ 483#define HTTP_MAX_CONT_LINES 10 484 485/* Place into which to build a header from one or several lines */ 486typedef struct { 487 char *buf; /* buffer */ 488 size_t bufsize; /* buffer size */ 489 size_t buflen; /* length of buffer contents */ 490} http_headerbuf_t; 491 492static void 493init_http_headerbuf(http_headerbuf_t *buf) 494{ 495 buf->buf = NULL; 496 buf->bufsize = 0; 497 buf->buflen = 0; 498} 499 500static void 501clean_http_headerbuf(http_headerbuf_t *buf) 502{ 503 if (buf->buf) 504 free(buf->buf); 505 init_http_headerbuf(buf); 506} 507 508/* Remove whitespace at the end of the buffer */ 509static void 510http_conn_trimright(conn_t *conn) 511{ 512 while (conn->buflen && 513 isspace((unsigned char)conn->buf[conn->buflen - 1])) 514 conn->buflen--; 515 conn->buf[conn->buflen] = '\0'; 516} 517 518static hdr_t 519http_next_header(conn_t *conn, http_headerbuf_t *hbuf, const char **p) 520{ 521 unsigned int i, len; 522 523 /* 524 * Have to do the stripping here because of the first line. So 525 * it's done twice for the subsequent lines. No big deal 526 */ 527 http_conn_trimright(conn); 528 if (conn->buflen == 0) 529 return (hdr_end); 530 531 /* Copy the line to the headerbuf */ 532 if (hbuf->bufsize < conn->buflen + 1) { 533 if ((hbuf->buf = realloc(hbuf->buf, conn->buflen + 1)) == NULL) 534 return (hdr_syserror); 535 hbuf->bufsize = conn->buflen + 1; 536 } 537 strcpy(hbuf->buf, conn->buf); 538 hbuf->buflen = conn->buflen; 539 540 /* 541 * Fetch possible continuation lines. Stop at 1st non-continuation 542 * and leave it in the conn buffer 543 */ 544 for (i = 0; i < HTTP_MAX_CONT_LINES; i++) { 545 if (fetch_getln(conn) == -1) 546 return (hdr_syserror); 547 548 /* 549 * Note: we carry on the idea from the previous version 550 * that a pure whitespace line is equivalent to an empty 551 * one (so it's not continuation and will be handled when 552 * we are called next) 553 */ 554 http_conn_trimright(conn); 555 if (conn->buf[0] != ' ' && conn->buf[0] != "\t"[0]) 556 break; 557 558 /* Got a continuation line. Concatenate to previous */ 559 len = hbuf->buflen + conn->buflen; 560 if (hbuf->bufsize < len + 1) { 561 len *= 2; 562 if ((hbuf->buf = realloc(hbuf->buf, len + 1)) == NULL) 563 return (hdr_syserror); 564 hbuf->bufsize = len + 1; 565 } 566 strcpy(hbuf->buf + hbuf->buflen, conn->buf); 567 hbuf->buflen += conn->buflen; 568 } 569 570 /* 571 * We could check for malformed headers but we don't really care. 572 * A valid header starts with a token immediately followed by a 573 * colon; a token is any sequence of non-control, non-whitespace 574 * characters except "()<>@,;:\\\"{}". 575 */ 576 for (i = 0; hdr_names[i].num != hdr_unknown; i++) 577 if ((*p = http_match(hdr_names[i].name, hbuf->buf)) != NULL) 578 return (hdr_names[i].num); 579 580 return (hdr_unknown); 581} 582 583/************************** 584 * [Proxy-]Authenticate header parsing 585 */ 586 587/* 588 * Read doublequote-delimited string into output buffer obuf (allocated 589 * by caller, whose responsibility it is to ensure that it's big enough) 590 * cp points to the first char after the initial '"' 591 * Handles \ quoting 592 * Returns pointer to the first char after the terminating double quote, or 593 * NULL for error. 594 */ 595static const char * 596http_parse_headerstring(const char *cp, char *obuf) 597{ 598 for (;;) { 599 switch (*cp) { 600 case 0: /* Unterminated string */ 601 *obuf = 0; 602 return (NULL); 603 case '"': /* Ending quote */ 604 *obuf = 0; 605 return (++cp); 606 case '\\': 607 if (*++cp == 0) { 608 *obuf = 0; 609 return (NULL); 610 } 611 /* FALLTHROUGH */ 612 default: 613 *obuf++ = *cp++; 614 } 615 } 616} 617 618/* Http auth challenge schemes */ 619typedef enum {HTTPAS_UNKNOWN, HTTPAS_BASIC,HTTPAS_DIGEST} http_auth_schemes_t; 620 621/* Data holder for a Basic or Digest challenge. */ 622typedef struct { 623 http_auth_schemes_t scheme; 624 char *realm; 625 char *qop; 626 char *nonce; 627 char *opaque; 628 char *algo; 629 int stale; 630 int nc; /* Nonce count */ 631} http_auth_challenge_t; 632 633static void 634init_http_auth_challenge(http_auth_challenge_t *b) 635{ 636 b->scheme = HTTPAS_UNKNOWN; 637 b->realm = b->qop = b->nonce = b->opaque = b->algo = NULL; 638 b->stale = b->nc = 0; 639} 640 641static void 642clean_http_auth_challenge(http_auth_challenge_t *b) 643{ 644 if (b->realm) 645 free(b->realm); 646 if (b->qop) 647 free(b->qop); 648 if (b->nonce) 649 free(b->nonce); 650 if (b->opaque) 651 free(b->opaque); 652 if (b->algo) 653 free(b->algo); 654 init_http_auth_challenge(b); 655} 656 657/* Data holder for an array of challenges offered in an http response. */ 658#define MAX_CHALLENGES 10 659typedef struct { 660 http_auth_challenge_t *challenges[MAX_CHALLENGES]; 661 int count; /* Number of parsed challenges in the array */ 662 int valid; /* We did parse an authenticate header */ 663} http_auth_challenges_t; 664 665static void 666init_http_auth_challenges(http_auth_challenges_t *cs) 667{ 668 int i; 669 for (i = 0; i < MAX_CHALLENGES; i++) 670 cs->challenges[i] = NULL; 671 cs->count = cs->valid = 0; 672} 673 674static void 675clean_http_auth_challenges(http_auth_challenges_t *cs) 676{ 677 int i; 678 /* We rely on non-zero pointers being allocated, not on the count */ 679 for (i = 0; i < MAX_CHALLENGES; i++) { 680 if (cs->challenges[i] != NULL) { 681 clean_http_auth_challenge(cs->challenges[i]); 682 free(cs->challenges[i]); 683 } 684 } 685 init_http_auth_challenges(cs); 686} 687 688/* 689 * Enumeration for lexical elements. Separators will be returned as their own 690 * ascii value 691 */ 692typedef enum {HTTPHL_WORD=256, HTTPHL_STRING=257, HTTPHL_END=258, 693 HTTPHL_ERROR = 259} http_header_lex_t; 694 695/* 696 * Determine what kind of token comes next and return possible value 697 * in buf, which is supposed to have been allocated big enough by 698 * caller. Advance input pointer and return element type. 699 */ 700static int 701http_header_lex(const char **cpp, char *buf) 702{ 703 size_t l; 704 /* Eat initial whitespace */ 705 *cpp += strspn(*cpp, " \t"); 706 if (**cpp == 0) 707 return (HTTPHL_END); 708 709 /* Separator ? */ 710 if (**cpp == ',' || **cpp == '=') 711 return (*((*cpp)++)); 712 713 /* String ? */ 714 if (**cpp == '"') { 715 *cpp = http_parse_headerstring(++*cpp, buf); 716 if (*cpp == NULL) 717 return (HTTPHL_ERROR); 718 return (HTTPHL_STRING); 719 } 720 721 /* Read other token, until separator or whitespace */ 722 l = strcspn(*cpp, " \t,="); 723 memcpy(buf, *cpp, l); 724 buf[l] = 0; 725 *cpp += l; 726 return (HTTPHL_WORD); 727} 728 729/* 730 * Read challenges from http xxx-authenticate header and accumulate them 731 * in the challenges list structure. 732 * 733 * Headers with multiple challenges are specified by rfc2617, but 734 * servers (ie: squid) often send them in separate headers instead, 735 * which in turn is forbidden by the http spec (multiple headers with 736 * the same name are only allowed for pure comma-separated lists, see 737 * rfc2616 sec 4.2). 738 * 739 * We support both approaches anyway 740 */ 741static int 742http_parse_authenticate(const char *cp, http_auth_challenges_t *cs) 743{ 744 int ret = -1; 745 http_header_lex_t lex; 746 char *key = malloc(strlen(cp) + 1); 747 char *value = malloc(strlen(cp) + 1); 748 char *buf = malloc(strlen(cp) + 1); 749 750 if (key == NULL || value == NULL || buf == NULL) { 751 fetch_syserr(); 752 goto out; 753 } 754 755 /* In any case we've seen the header and we set the valid bit */ 756 cs->valid = 1; 757 758 /* Need word first */ 759 lex = http_header_lex(&cp, key); 760 if (lex != HTTPHL_WORD) 761 goto out; 762 763 /* Loop on challenges */ 764 for (; cs->count < MAX_CHALLENGES; cs->count++) { 765 cs->challenges[cs->count] = 766 malloc(sizeof(http_auth_challenge_t)); 767 if (cs->challenges[cs->count] == NULL) { 768 fetch_syserr(); 769 goto out; 770 } 771 init_http_auth_challenge(cs->challenges[cs->count]); 772 if (!strcasecmp(key, "basic")) { 773 cs->challenges[cs->count]->scheme = HTTPAS_BASIC; 774 } else if (!strcasecmp(key, "digest")) { 775 cs->challenges[cs->count]->scheme = HTTPAS_DIGEST; 776 } else { 777 cs->challenges[cs->count]->scheme = HTTPAS_UNKNOWN; 778 /* 779 * Continue parsing as basic or digest may 780 * follow, and the syntax is the same for 781 * all. We'll just ignore this one when 782 * looking at the list 783 */ 784 } 785 786 /* Loop on attributes */ 787 for (;;) { 788 /* Key */ 789 lex = http_header_lex(&cp, key); 790 if (lex != HTTPHL_WORD) 791 goto out; 792 793 /* Equal sign */ 794 lex = http_header_lex(&cp, buf); 795 if (lex != '=') 796 goto out; 797 798 /* Value */ 799 lex = http_header_lex(&cp, value); 800 if (lex != HTTPHL_WORD && lex != HTTPHL_STRING) 801 goto out; 802 803 if (!strcasecmp(key, "realm")) 804 cs->challenges[cs->count]->realm = 805 strdup(value); 806 else if (!strcasecmp(key, "qop")) 807 cs->challenges[cs->count]->qop = 808 strdup(value); 809 else if (!strcasecmp(key, "nonce")) 810 cs->challenges[cs->count]->nonce = 811 strdup(value); 812 else if (!strcasecmp(key, "opaque")) 813 cs->challenges[cs->count]->opaque = 814 strdup(value); 815 else if (!strcasecmp(key, "algorithm")) 816 cs->challenges[cs->count]->algo = 817 strdup(value); 818 else if (!strcasecmp(key, "stale")) 819 cs->challenges[cs->count]->stale = 820 strcasecmp(value, "no"); 821 /* Else ignore unknown attributes */ 822 823 /* Comma or Next challenge or End */ 824 lex = http_header_lex(&cp, key); 825 /* 826 * If we get a word here, this is the beginning of the 827 * next challenge. Break the attributes loop 828 */ 829 if (lex == HTTPHL_WORD) 830 break; 831 832 if (lex == HTTPHL_END) { 833 /* End while looking for ',' is normal exit */ 834 cs->count++; 835 ret = 0; 836 goto out; 837 } 838 /* Anything else is an error */ 839 if (lex != ',') 840 goto out; 841 842 } /* End attributes loop */ 843 } /* End challenge loop */ 844 845 /* 846 * Challenges max count exceeded. This really can't happen 847 * with normal data, something's fishy -> error 848 */ 849 850out: 851 if (key) 852 free(key); 853 if (value) 854 free(value); 855 if (buf) 856 free(buf); 857 return (ret); 858} 859 860 861/* 862 * Parse a last-modified header 863 */ 864static int 865http_parse_mtime(const char *p, time_t *mtime) 866{ 867 char locale[64], *r; 868 struct tm tm; 869 870 strncpy(locale, setlocale(LC_TIME, NULL), sizeof(locale)); 871 setlocale(LC_TIME, "C"); 872 r = strptime(p, "%a, %d %b %Y %H:%M:%S GMT", &tm); 873 /* XXX should add support for date-2 and date-3 */ 874 setlocale(LC_TIME, locale); 875 if (r == NULL) 876 return (-1); 877 DEBUG(fprintf(stderr, "last modified: [%04d-%02d-%02d " 878 "%02d:%02d:%02d]\n", 879 tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, 880 tm.tm_hour, tm.tm_min, tm.tm_sec)); 881 *mtime = timegm(&tm); 882 return (0); 883} 884 885/* 886 * Parse a content-length header 887 */ 888static int 889http_parse_length(const char *p, off_t *length) 890{ 891 off_t len; 892 893 for (len = 0; *p && isdigit((unsigned char)*p); ++p) 894 len = len * 10 + (*p - '0'); 895 if (*p) 896 return (-1); 897 DEBUG(fprintf(stderr, "content length: [%lld]\n", 898 (long long)len)); 899 *length = len; 900 return (0); 901} 902 903/* 904 * Parse a content-range header 905 */ 906static int 907http_parse_range(const char *p, off_t *offset, off_t *length, off_t *size) 908{ 909 off_t first, last, len; 910 911 if (strncasecmp(p, "bytes ", 6) != 0) 912 return (-1); 913 p += 6; 914 if (*p == '*') { 915 first = last = -1; 916 ++p; 917 } else { 918 for (first = 0; *p && isdigit((unsigned char)*p); ++p) 919 first = first * 10 + *p - '0'; 920 if (*p != '-') 921 return (-1); 922 for (last = 0, ++p; *p && isdigit((unsigned char)*p); ++p) 923 last = last * 10 + *p - '0'; 924 } 925 if (first > last || *p != '/') 926 return (-1); 927 for (len = 0, ++p; *p && isdigit((unsigned char)*p); ++p) 928 len = len * 10 + *p - '0'; 929 if (*p || len < last - first + 1) 930 return (-1); 931 if (first == -1) { 932 DEBUG(fprintf(stderr, "content range: [*/%lld]\n", 933 (long long)len)); 934 *length = 0; 935 } else { 936 DEBUG(fprintf(stderr, "content range: [%lld-%lld/%lld]\n", 937 (long long)first, (long long)last, (long long)len)); 938 *length = last - first + 1; 939 } 940 *offset = first; 941 *size = len; 942 return (0); 943} 944 945 946/***************************************************************************** 947 * Helper functions for authorization 948 */ 949 950/* 951 * Base64 encoding 952 */ 953static char * 954http_base64(const char *src) 955{ 956 static const char base64[] = 957 "ABCDEFGHIJKLMNOPQRSTUVWXYZ" 958 "abcdefghijklmnopqrstuvwxyz" 959 "0123456789+/"; 960 char *str, *dst; 961 size_t l; 962 int t, r; 963 964 l = strlen(src); 965 if ((str = malloc(((l + 2) / 3) * 4 + 1)) == NULL) 966 return (NULL); 967 dst = str; 968 r = 0; 969 970 while (l >= 3) { 971 t = (src[0] << 16) | (src[1] << 8) | src[2]; 972 dst[0] = base64[(t >> 18) & 0x3f]; 973 dst[1] = base64[(t >> 12) & 0x3f]; 974 dst[2] = base64[(t >> 6) & 0x3f]; 975 dst[3] = base64[(t >> 0) & 0x3f]; 976 src += 3; l -= 3; 977 dst += 4; r += 4; 978 } 979 980 switch (l) { 981 case 2: 982 t = (src[0] << 16) | (src[1] << 8); 983 dst[0] = base64[(t >> 18) & 0x3f]; 984 dst[1] = base64[(t >> 12) & 0x3f]; 985 dst[2] = base64[(t >> 6) & 0x3f]; 986 dst[3] = '='; 987 dst += 4; 988 r += 4; 989 break; 990 case 1: 991 t = src[0] << 16; 992 dst[0] = base64[(t >> 18) & 0x3f]; 993 dst[1] = base64[(t >> 12) & 0x3f]; 994 dst[2] = dst[3] = '='; 995 dst += 4; 996 r += 4; 997 break; 998 case 0: 999 break; 1000 } 1001 1002 *dst = 0; 1003 return (str); 1004} 1005 1006 1007/* 1008 * Extract authorization parameters from environment value. 1009 * The value is like scheme:realm:user:pass 1010 */ 1011typedef struct { 1012 char *scheme; 1013 char *realm; 1014 char *user; 1015 char *password; 1016} http_auth_params_t; 1017 1018static void 1019init_http_auth_params(http_auth_params_t *s) 1020{ 1021 s->scheme = s->realm = s->user = s->password = 0; 1022} 1023 1024static void 1025clean_http_auth_params(http_auth_params_t *s) 1026{ 1027 if (s->scheme) 1028 free(s->scheme); 1029 if (s->realm) 1030 free(s->realm); 1031 if (s->user) 1032 free(s->user); 1033 if (s->password) 1034 free(s->password); 1035 init_http_auth_params(s); 1036} 1037 1038static int 1039http_authfromenv(const char *p, http_auth_params_t *parms) 1040{ 1041 int ret = -1; 1042 char *v, *ve; 1043 char *str = strdup(p); 1044 1045 if (str == NULL) { 1046 fetch_syserr(); 1047 return (-1); 1048 } 1049 v = str; 1050 1051 if ((ve = strchr(v, ':')) == NULL) 1052 goto out; 1053 1054 *ve = 0; 1055 if ((parms->scheme = strdup(v)) == NULL) { 1056 fetch_syserr(); 1057 goto out; 1058 } 1059 v = ve + 1; 1060 1061 if ((ve = strchr(v, ':')) == NULL) 1062 goto out; 1063 1064 *ve = 0; 1065 if ((parms->realm = strdup(v)) == NULL) { 1066 fetch_syserr(); 1067 goto out; 1068 } 1069 v = ve + 1; 1070 1071 if ((ve = strchr(v, ':')) == NULL) 1072 goto out; 1073 1074 *ve = 0; 1075 if ((parms->user = strdup(v)) == NULL) { 1076 fetch_syserr(); 1077 goto out; 1078 } 1079 v = ve + 1; 1080 1081 1082 if ((parms->password = strdup(v)) == NULL) { 1083 fetch_syserr(); 1084 goto out; 1085 } 1086 ret = 0; 1087out: 1088 if (ret == -1) 1089 clean_http_auth_params(parms); 1090 if (str) 1091 free(str); 1092 return (ret); 1093} 1094 1095 1096/* 1097 * Digest response: the code to compute the digest is taken from the 1098 * sample implementation in RFC2616 1099 */ 1100#define IN const 1101#define OUT 1102 1103#define HASHLEN 16 1104typedef char HASH[HASHLEN]; 1105#define HASHHEXLEN 32 1106typedef char HASHHEX[HASHHEXLEN+1]; 1107 1108static const char *hexchars = "0123456789abcdef"; 1109static void 1110CvtHex(IN HASH Bin, OUT HASHHEX Hex) 1111{ 1112 unsigned short i; 1113 unsigned char j; 1114 1115 for (i = 0; i < HASHLEN; i++) { 1116 j = (Bin[i] >> 4) & 0xf; 1117 Hex[i*2] = hexchars[j]; 1118 j = Bin[i] & 0xf; 1119 Hex[i*2+1] = hexchars[j]; 1120 }; 1121 Hex[HASHHEXLEN] = '\0'; 1122}; 1123 1124/* calculate H(A1) as per spec */ 1125static void 1126DigestCalcHA1( 1127 IN char * pszAlg, 1128 IN char * pszUserName, 1129 IN char * pszRealm, 1130 IN char * pszPassword, 1131 IN char * pszNonce, 1132 IN char * pszCNonce, 1133 OUT HASHHEX SessionKey 1134 ) 1135{ 1136 MD5_CTX Md5Ctx; 1137 HASH HA1; 1138 1139 MD5Init(&Md5Ctx); 1140 MD5Update(&Md5Ctx, pszUserName, strlen(pszUserName)); 1141 MD5Update(&Md5Ctx, ":", 1); 1142 MD5Update(&Md5Ctx, pszRealm, strlen(pszRealm)); 1143 MD5Update(&Md5Ctx, ":", 1); 1144 MD5Update(&Md5Ctx, pszPassword, strlen(pszPassword)); 1145 MD5Final(HA1, &Md5Ctx); 1146 if (strcasecmp(pszAlg, "md5-sess") == 0) { 1147 1148 MD5Init(&Md5Ctx); 1149 MD5Update(&Md5Ctx, HA1, HASHLEN); 1150 MD5Update(&Md5Ctx, ":", 1); 1151 MD5Update(&Md5Ctx, pszNonce, strlen(pszNonce)); 1152 MD5Update(&Md5Ctx, ":", 1); 1153 MD5Update(&Md5Ctx, pszCNonce, strlen(pszCNonce)); 1154 MD5Final(HA1, &Md5Ctx); 1155 }; 1156 CvtHex(HA1, SessionKey); 1157} 1158 1159/* calculate request-digest/response-digest as per HTTP Digest spec */ 1160static void 1161DigestCalcResponse( 1162 IN HASHHEX HA1, /* H(A1) */ 1163 IN char * pszNonce, /* nonce from server */ 1164 IN char * pszNonceCount, /* 8 hex digits */ 1165 IN char * pszCNonce, /* client nonce */ 1166 IN char * pszQop, /* qop-value: "", "auth", "auth-int" */ 1167 IN char * pszMethod, /* method from the request */ 1168 IN char * pszDigestUri, /* requested URL */ 1169 IN HASHHEX HEntity, /* H(entity body) if qop="auth-int" */ 1170 OUT HASHHEX Response /* request-digest or response-digest */ 1171 ) 1172{ 1173/* DEBUG(fprintf(stderr, 1174 "Calc: HA1[%s] Nonce[%s] qop[%s] method[%s] URI[%s]\n", 1175 HA1, pszNonce, pszQop, pszMethod, pszDigestUri));*/ 1176 MD5_CTX Md5Ctx; 1177 HASH HA2; 1178 HASH RespHash; 1179 HASHHEX HA2Hex; 1180 1181 // calculate H(A2) 1182 MD5Init(&Md5Ctx); 1183 MD5Update(&Md5Ctx, pszMethod, strlen(pszMethod)); 1184 MD5Update(&Md5Ctx, ":", 1); 1185 MD5Update(&Md5Ctx, pszDigestUri, strlen(pszDigestUri)); 1186 if (strcasecmp(pszQop, "auth-int") == 0) { 1187 MD5Update(&Md5Ctx, ":", 1); 1188 MD5Update(&Md5Ctx, HEntity, HASHHEXLEN); 1189 }; 1190 MD5Final(HA2, &Md5Ctx); 1191 CvtHex(HA2, HA2Hex); 1192 1193 // calculate response 1194 MD5Init(&Md5Ctx); 1195 MD5Update(&Md5Ctx, HA1, HASHHEXLEN); 1196 MD5Update(&Md5Ctx, ":", 1); 1197 MD5Update(&Md5Ctx, pszNonce, strlen(pszNonce)); 1198 MD5Update(&Md5Ctx, ":", 1); 1199 if (*pszQop) { 1200 MD5Update(&Md5Ctx, pszNonceCount, strlen(pszNonceCount)); 1201 MD5Update(&Md5Ctx, ":", 1); 1202 MD5Update(&Md5Ctx, pszCNonce, strlen(pszCNonce)); 1203 MD5Update(&Md5Ctx, ":", 1); 1204 MD5Update(&Md5Ctx, pszQop, strlen(pszQop)); 1205 MD5Update(&Md5Ctx, ":", 1); 1206 }; 1207 MD5Update(&Md5Ctx, HA2Hex, HASHHEXLEN); 1208 MD5Final(RespHash, &Md5Ctx); 1209 CvtHex(RespHash, Response); 1210} 1211 1212/* 1213 * Generate/Send a Digest authorization header 1214 * This looks like: [Proxy-]Authorization: credentials 1215 * 1216 * credentials = "Digest" digest-response 1217 * digest-response = 1#( username | realm | nonce | digest-uri 1218 * | response | [ algorithm ] | [cnonce] | 1219 * [opaque] | [message-qop] | 1220 * [nonce-count] | [auth-param] ) 1221 * username = "username" "=" username-value 1222 * username-value = quoted-string 1223 * digest-uri = "uri" "=" digest-uri-value 1224 * digest-uri-value = request-uri ; As specified by HTTP/1.1 1225 * message-qop = "qop" "=" qop-value 1226 * cnonce = "cnonce" "=" cnonce-value 1227 * cnonce-value = nonce-value 1228 * nonce-count = "nc" "=" nc-value 1229 * nc-value = 8LHEX 1230 * response = "response" "=" request-digest 1231 * request-digest = <"> 32LHEX <"> 1232 */ 1233static int 1234http_digest_auth(conn_t *conn, const char *hdr, http_auth_challenge_t *c, 1235 http_auth_params_t *parms, struct url *url) 1236{ 1237 int r; 1238 char noncecount[10]; 1239 char cnonce[40]; 1240 char *options = 0; 1241 1242 if (!c->realm || !c->nonce) { 1243 DEBUG(fprintf(stderr, "realm/nonce not set in challenge\n")); 1244 return(-1); 1245 } 1246 if (!c->algo) 1247 c->algo = strdup(""); 1248 1249 if (asprintf(&options, "%s%s%s%s", 1250 *c->algo? ",algorithm=" : "", c->algo, 1251 c->opaque? ",opaque=" : "", c->opaque?c->opaque:"")== -1) 1252 return (-1); 1253 1254 if (!c->qop) { 1255 c->qop = strdup(""); 1256 *noncecount = 0; 1257 *cnonce = 0; 1258 } else { 1259 c->nc++; 1260 sprintf(noncecount, "%08x", c->nc); 1261 /* We don't try very hard with the cnonce ... */ 1262 sprintf(cnonce, "%x%lx", getpid(), (unsigned long)time(0)); 1263 } 1264 1265 HASHHEX HA1; 1266 DigestCalcHA1(c->algo, parms->user, c->realm, 1267 parms->password, c->nonce, cnonce, HA1); 1268 DEBUG(fprintf(stderr, "HA1: [%s]\n", HA1)); 1269 HASHHEX digest; 1270 DigestCalcResponse(HA1, c->nonce, noncecount, cnonce, c->qop, 1271 "GET", url->doc, "", digest); 1272 1273 if (c->qop[0]) { 1274 r = http_cmd(conn, "%s: Digest username=\"%s\",realm=\"%s\"," 1275 "nonce=\"%s\",uri=\"%s\",response=\"%s\"," 1276 "qop=\"auth\", cnonce=\"%s\", nc=%s%s", 1277 hdr, parms->user, c->realm, 1278 c->nonce, url->doc, digest, 1279 cnonce, noncecount, options); 1280 } else { 1281 r = http_cmd(conn, "%s: Digest username=\"%s\",realm=\"%s\"," 1282 "nonce=\"%s\",uri=\"%s\",response=\"%s\"%s", 1283 hdr, parms->user, c->realm, 1284 c->nonce, url->doc, digest, options); 1285 } 1286 if (options) 1287 free(options); 1288 return (r); 1289} 1290 1291/* 1292 * Encode username and password 1293 */ 1294static int 1295http_basic_auth(conn_t *conn, const char *hdr, const char *usr, const char *pwd) 1296{ 1297 char *upw, *auth; 1298 int r; 1299 1300 DEBUG(fprintf(stderr, "basic: usr: [%s]\n", usr)); 1301 DEBUG(fprintf(stderr, "basic: pwd: [%s]\n", pwd)); 1302 if (asprintf(&upw, "%s:%s", usr, pwd) == -1) 1303 return (-1); 1304 auth = http_base64(upw); 1305 free(upw); 1306 if (auth == NULL) 1307 return (-1); 1308 r = http_cmd(conn, "%s: Basic %s", hdr, auth); 1309 free(auth); 1310 return (r); 1311} 1312 1313/* 1314 * Chose the challenge to answer and call the appropriate routine to 1315 * produce the header. 1316 */ 1317static int 1318http_authorize(conn_t *conn, const char *hdr, http_auth_challenges_t *cs, 1319 http_auth_params_t *parms, struct url *url) 1320{ 1321 http_auth_challenge_t *basic = NULL; 1322 http_auth_challenge_t *digest = NULL; 1323 int i; 1324 1325 /* If user or pass are null we're not happy */ 1326 if (!parms->user || !parms->password) { 1327 DEBUG(fprintf(stderr, "NULL usr or pass\n")); 1328 return (-1); 1329 } 1330 1331 /* Look for a Digest and a Basic challenge */ 1332 for (i = 0; i < cs->count; i++) { 1333 if (cs->challenges[i]->scheme == HTTPAS_BASIC) 1334 basic = cs->challenges[i]; 1335 if (cs->challenges[i]->scheme == HTTPAS_DIGEST) 1336 digest = cs->challenges[i]; 1337 } 1338 1339 /* Error if "Digest" was specified and there is no Digest challenge */ 1340 if (!digest && (parms->scheme && 1341 !strcasecmp(parms->scheme, "digest"))) { 1342 DEBUG(fprintf(stderr, 1343 "Digest auth in env, not supported by peer\n")); 1344 return (-1); 1345 } 1346 /* 1347 * If "basic" was specified in the environment, or there is no Digest 1348 * challenge, do the basic thing. Don't need a challenge for this, 1349 * so no need to check basic!=NULL 1350 */ 1351 if (!digest || (parms->scheme && !strcasecmp(parms->scheme,"basic"))) 1352 return (http_basic_auth(conn,hdr,parms->user,parms->password)); 1353 1354 /* Else, prefer digest. We just checked that it's not NULL */ 1355 return (http_digest_auth(conn, hdr, digest, parms, url)); 1356} 1357 1358/***************************************************************************** 1359 * Helper functions for connecting to a server or proxy 1360 */ 1361 1362/* 1363 * Connect to the correct HTTP server or proxy. 1364 */ 1365static conn_t * 1366http_connect(struct url *URL, struct url *purl, const char *flags) 1367{ 1368 conn_t *conn; 1369 int verbose; 1370 int af, val; 1371 1372#ifdef INET6 1373 af = AF_UNSPEC; 1374#else 1375 af = AF_INET; 1376#endif 1377 1378 verbose = CHECK_FLAG('v'); 1379 if (CHECK_FLAG('4')) 1380 af = AF_INET; 1381#ifdef INET6 1382 else if (CHECK_FLAG('6')) 1383 af = AF_INET6; 1384#endif 1385 1386 if (purl && strcasecmp(URL->scheme, SCHEME_HTTPS) != 0) { 1387 URL = purl; 1388 } else if (strcasecmp(URL->scheme, SCHEME_FTP) == 0) { 1389 /* can't talk http to an ftp server */ 1390 /* XXX should set an error code */ 1391 return (NULL); 1392 } 1393 1394 if ((conn = fetch_connect(URL->host, URL->port, af, verbose)) == NULL) 1395 /* fetch_connect() has already set an error code */ 1396 return (NULL); 1397 if (strcasecmp(URL->scheme, SCHEME_HTTPS) == 0 && 1398 fetch_ssl(conn, verbose) == -1) { 1399 fetch_close(conn); 1400 /* grrr */ 1401 errno = EAUTH; 1402 fetch_syserr(); 1403 return (NULL); 1404 } 1405 1406 val = 1; 1407 setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, sizeof(val)); 1408 1409 return (conn); 1410} 1411 1412static struct url * 1413http_get_proxy(struct url * url, const char *flags) 1414{ 1415 struct url *purl; 1416 char *p; 1417 1418 if (flags != NULL && strchr(flags, 'd') != NULL) 1419 return (NULL); 1420 if (fetch_no_proxy_match(url->host)) 1421 return (NULL); 1422 if (((p = getenv("HTTP_PROXY")) || (p = getenv("http_proxy"))) && 1423 *p && (purl = fetchParseURL(p))) { 1424 if (!*purl->scheme) 1425 strcpy(purl->scheme, SCHEME_HTTP); 1426 if (!purl->port) 1427 purl->port = fetch_default_proxy_port(purl->scheme); 1428 if (strcasecmp(purl->scheme, SCHEME_HTTP) == 0) 1429 return (purl); 1430 fetchFreeURL(purl); 1431 } 1432 return (NULL); 1433} 1434 1435static void 1436http_print_html(FILE *out, FILE *in) 1437{ 1438 size_t len; 1439 char *line, *p, *q; 1440 int comment, tag; 1441 1442 comment = tag = 0; 1443 while ((line = fgetln(in, &len)) != NULL) { 1444 while (len && isspace((unsigned char)line[len - 1])) 1445 --len; 1446 for (p = q = line; q < line + len; ++q) { 1447 if (comment && *q == '-') { 1448 if (q + 2 < line + len && 1449 strcmp(q, "-->") == 0) { 1450 tag = comment = 0; 1451 q += 2; 1452 } 1453 } else if (tag && !comment && *q == '>') { 1454 p = q + 1; 1455 tag = 0; 1456 } else if (!tag && *q == '<') { 1457 if (q > p) 1458 fwrite(p, q - p, 1, out); 1459 tag = 1; 1460 if (q + 3 < line + len && 1461 strcmp(q, "<!--") == 0) { 1462 comment = 1; 1463 q += 3; 1464 } 1465 } 1466 } 1467 if (!tag && q > p) 1468 fwrite(p, q - p, 1, out); 1469 fputc('\n', out); 1470 } 1471} 1472 1473 1474/***************************************************************************** 1475 * Core 1476 */ 1477 1478/* 1479 * Send a request and process the reply 1480 * 1481 * XXX This function is way too long, the do..while loop should be split 1482 * XXX off into a separate function. 1483 */ 1484FILE * 1485http_request(struct url *URL, const char *op, struct url_stat *us, 1486 struct url *purl, const char *flags) 1487{ 1488 char timebuf[80]; 1489 char hbuf[MAXHOSTNAMELEN + 7], *host; 1490 conn_t *conn; 1491 struct url *url, *new; 1492 int chunked, direct, ims, noredirect, verbose; 1493 int e, i, n, val; 1494 off_t offset, clength, length, size; 1495 time_t mtime; 1496 const char *p; 1497 FILE *f; 1498 hdr_t h; 1499 struct tm *timestruct; 1500 http_headerbuf_t headerbuf; 1501 http_auth_challenges_t server_challenges; 1502 http_auth_challenges_t proxy_challenges; 1503 1504 /* The following calls don't allocate anything */ 1505 init_http_headerbuf(&headerbuf); 1506 init_http_auth_challenges(&server_challenges); 1507 init_http_auth_challenges(&proxy_challenges); 1508 1509 direct = CHECK_FLAG('d'); 1510 noredirect = CHECK_FLAG('A'); 1511 verbose = CHECK_FLAG('v'); 1512 ims = CHECK_FLAG('i'); 1513 1514 if (direct && purl) { 1515 fetchFreeURL(purl); 1516 purl = NULL; 1517 } 1518 1519 /* try the provided URL first */ 1520 url = URL; 1521 1522 n = MAX_REDIRECT; 1523 i = 0; 1524 1525 e = HTTP_PROTOCOL_ERROR; 1526 do { 1527 new = NULL; 1528 chunked = 0; 1529 offset = 0; 1530 clength = -1; 1531 length = -1; 1532 size = -1; 1533 mtime = 0; 1534 1535 /* check port */ 1536 if (!url->port) 1537 url->port = fetch_default_port(url->scheme); 1538 1539 /* were we redirected to an FTP URL? */ 1540 if (purl == NULL && strcmp(url->scheme, SCHEME_FTP) == 0) { 1541 if (strcmp(op, "GET") == 0) 1542 return (ftp_request(url, "RETR", us, purl, flags)); 1543 else if (strcmp(op, "HEAD") == 0) 1544 return (ftp_request(url, "STAT", us, purl, flags)); 1545 } 1546 1547 /* connect to server or proxy */ 1548 if ((conn = http_connect(url, purl, flags)) == NULL) 1549 goto ouch; 1550 1551 host = url->host; 1552#ifdef INET6 1553 if (strchr(url->host, ':')) { 1554 snprintf(hbuf, sizeof(hbuf), "[%s]", url->host); 1555 host = hbuf; 1556 } 1557#endif 1558 if (url->port != fetch_default_port(url->scheme)) { 1559 if (host != hbuf) { 1560 strcpy(hbuf, host); 1561 host = hbuf; 1562 } 1563 snprintf(hbuf + strlen(hbuf), 1564 sizeof(hbuf) - strlen(hbuf), ":%d", url->port); 1565 } 1566 1567 /* send request */ 1568 if (verbose) 1569 fetch_info("requesting %s://%s%s", 1570 url->scheme, host, url->doc); 1571 if (purl) { 1572 http_cmd(conn, "%s %s://%s%s HTTP/1.1", 1573 op, url->scheme, host, url->doc); 1574 } else { 1575 http_cmd(conn, "%s %s HTTP/1.1", 1576 op, url->doc); 1577 } 1578 1579 if (ims && url->ims_time) { 1580 timestruct = gmtime((time_t *)&url->ims_time); 1581 (void)strftime(timebuf, 80, "%a, %d %b %Y %T GMT", 1582 timestruct); 1583 if (verbose) 1584 fetch_info("If-Modified-Since: %s", timebuf); 1585 http_cmd(conn, "If-Modified-Since: %s", timebuf); 1586 } 1587 /* virtual host */ 1588 http_cmd(conn, "Host: %s", host); 1589 1590 /* 1591 * Proxy authorization: we only send auth after we received 1592 * a 407 error. We do not first try basic anyway (changed 1593 * when support was added for digest-auth) 1594 */ 1595 if (purl && proxy_challenges.valid) { 1596 http_auth_params_t aparams; 1597 init_http_auth_params(&aparams); 1598 if (*purl->user || *purl->pwd) { 1599 aparams.user = purl->user ? 1600 strdup(purl->user) : strdup(""); 1601 aparams.password = purl->pwd? 1602 strdup(purl->pwd) : strdup(""); 1603 } else if ((p = getenv("HTTP_PROXY_AUTH")) != NULL && 1604 *p != '\0') { 1605 if (http_authfromenv(p, &aparams) < 0) { 1606 http_seterr(HTTP_NEED_PROXY_AUTH); 1607 goto ouch; 1608 } 1609 } 1610 http_authorize(conn, "Proxy-Authorization", 1611 &proxy_challenges, &aparams, url); 1612 clean_http_auth_params(&aparams); 1613 } 1614 1615 /* 1616 * Server authorization: we never send "a priori" 1617 * Basic auth, which used to be done if user/pass were 1618 * set in the url. This would be weird because we'd send the 1619 * password in the clear even if Digest is finally to be 1620 * used (it would have made more sense for the 1621 * pre-digest version to do this when Basic was specified 1622 * in the environment) 1623 */ 1624 if (server_challenges.valid) { 1625 http_auth_params_t aparams; 1626 init_http_auth_params(&aparams); 1627 if (*url->user || *url->pwd) { 1628 aparams.user = url->user ? 1629 strdup(url->user) : strdup(""); 1630 aparams.password = url->pwd ? 1631 strdup(url->pwd) : strdup(""); 1632 } else if ((p = getenv("HTTP_AUTH")) != NULL && 1633 *p != '\0') { 1634 if (http_authfromenv(p, &aparams) < 0) { 1635 http_seterr(HTTP_NEED_AUTH); 1636 goto ouch; 1637 } 1638 } else if (fetchAuthMethod && 1639 fetchAuthMethod(url) == 0) { 1640 aparams.user = url->user ? 1641 strdup(url->user) : strdup(""); 1642 aparams.password = url->pwd ? 1643 strdup(url->pwd) : strdup(""); 1644 } else { 1645 http_seterr(HTTP_NEED_AUTH); 1646 goto ouch; 1647 } 1648 http_authorize(conn, "Authorization", 1649 &server_challenges, &aparams, url); 1650 clean_http_auth_params(&aparams); 1651 } 1652 1653 /* other headers */ 1654 if ((p = getenv("HTTP_REFERER")) != NULL && *p != '\0') { 1655 if (strcasecmp(p, "auto") == 0) 1656 http_cmd(conn, "Referer: %s://%s%s", 1657 url->scheme, host, url->doc); 1658 else 1659 http_cmd(conn, "Referer: %s", p); 1660 } 1661 if ((p = getenv("HTTP_USER_AGENT")) != NULL && *p != '\0') 1662 http_cmd(conn, "User-Agent: %s", p); 1663 else 1664 http_cmd(conn, "User-Agent: %s " _LIBFETCH_VER, getprogname()); 1665 if (url->offset > 0) 1666 http_cmd(conn, "Range: bytes=%lld-", (long long)url->offset); 1667 http_cmd(conn, "Connection: close"); 1668 http_cmd(conn, ""); 1669 1670 /* 1671 * Force the queued request to be dispatched. Normally, one 1672 * would do this with shutdown(2) but squid proxies can be 1673 * configured to disallow such half-closed connections. To 1674 * be compatible with such configurations, fiddle with socket 1675 * options to force the pending data to be written. 1676 */ 1677 val = 0; 1678 setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, 1679 sizeof(val)); 1680 val = 1; 1681 setsockopt(conn->sd, IPPROTO_TCP, TCP_NODELAY, &val, 1682 sizeof(val)); 1683 1684 /* get reply */ 1685 switch (http_get_reply(conn)) { 1686 case HTTP_OK: 1687 case HTTP_PARTIAL: 1688 case HTTP_NOT_MODIFIED: 1689 /* fine */ 1690 break; 1691 case HTTP_MOVED_PERM: 1692 case HTTP_MOVED_TEMP: 1693 case HTTP_SEE_OTHER: 1694 case HTTP_USE_PROXY: 1695 /* 1696 * Not so fine, but we still have to read the 1697 * headers to get the new location. 1698 */ 1699 break; 1700 case HTTP_NEED_AUTH: 1701 if (server_challenges.valid) { 1702 /* 1703 * We already sent out authorization code, 1704 * so there's nothing more we can do. 1705 */ 1706 http_seterr(conn->err); 1707 goto ouch; 1708 } 1709 /* try again, but send the password this time */ 1710 if (verbose) 1711 fetch_info("server requires authorization"); 1712 break; 1713 case HTTP_NEED_PROXY_AUTH: 1714 if (proxy_challenges.valid) { 1715 /* 1716 * We already sent our proxy 1717 * authorization code, so there's 1718 * nothing more we can do. */ 1719 http_seterr(conn->err); 1720 goto ouch; 1721 } 1722 /* try again, but send the password this time */ 1723 if (verbose) 1724 fetch_info("proxy requires authorization"); 1725 break; 1726 case HTTP_BAD_RANGE: 1727 /* 1728 * This can happen if we ask for 0 bytes because 1729 * we already have the whole file. Consider this 1730 * a success for now, and check sizes later. 1731 */ 1732 break; 1733 case HTTP_PROTOCOL_ERROR: 1734 /* fall through */ 1735 case -1: 1736 fetch_syserr(); 1737 goto ouch; 1738 default: 1739 http_seterr(conn->err); 1740 if (!verbose) 1741 goto ouch; 1742 /* fall through so we can get the full error message */ 1743 } 1744 1745 /* get headers. http_next_header expects one line readahead */ 1746 if (fetch_getln(conn) == -1) { 1747 fetch_syserr(); 1748 goto ouch; 1749 } 1750 do { 1751 switch ((h = http_next_header(conn, &headerbuf, &p))) { 1752 case hdr_syserror: 1753 fetch_syserr(); 1754 goto ouch; 1755 case hdr_error: 1756 http_seterr(HTTP_PROTOCOL_ERROR); 1757 goto ouch; 1758 case hdr_content_length: 1759 http_parse_length(p, &clength); 1760 break; 1761 case hdr_content_range: 1762 http_parse_range(p, &offset, &length, &size); 1763 break; 1764 case hdr_last_modified: 1765 http_parse_mtime(p, &mtime); 1766 break; 1767 case hdr_location: 1768 if (!HTTP_REDIRECT(conn->err)) 1769 break; 1770 /* 1771 * if the A flag is set, we don't follow 1772 * temporary redirects. 1773 */ 1774 if (noredirect && 1775 conn->err != HTTP_MOVED_PERM && 1776 conn->err != HTTP_PERM_REDIRECT && 1777 conn->err != HTTP_USE_PROXY) { 1778 n = 1; 1779 break; 1780 } 1781 if (new) 1782 free(new); 1783 if (verbose) 1784 fetch_info("%d redirect to %s", conn->err, p); 1785 if (*p == '/') 1786 /* absolute path */ 1787 new = fetchMakeURL(url->scheme, url->host, url->port, p, 1788 url->user, url->pwd); 1789 else 1790 new = fetchParseURL(p); 1791 if (new == NULL) { 1792 /* XXX should set an error code */ 1793 DEBUG(fprintf(stderr, "failed to parse new URL\n")); 1794 goto ouch; 1795 } 1796 1797 /* Only copy credentials if the host matches */ 1798 if (!strcmp(new->host, url->host) && !*new->user && !*new->pwd) { 1799 strcpy(new->user, url->user); 1800 strcpy(new->pwd, url->pwd); 1801 } 1802 new->offset = url->offset; 1803 new->length = url->length; 1804 break; 1805 case hdr_transfer_encoding: 1806 /* XXX weak test*/ 1807 chunked = (strcasecmp(p, "chunked") == 0); 1808 break; 1809 case hdr_www_authenticate: 1810 if (conn->err != HTTP_NEED_AUTH) 1811 break; 1812 if (http_parse_authenticate(p, &server_challenges) == 0) 1813 ++n; 1814 break; 1815 case hdr_proxy_authenticate: 1816 if (conn->err != HTTP_NEED_PROXY_AUTH) 1817 break; 1818 if (http_parse_authenticate(p, &proxy_challenges) == 0) 1819 ++n; 1820 break; 1821 case hdr_end: 1822 /* fall through */ 1823 case hdr_unknown: 1824 /* ignore */ 1825 break; 1826 } 1827 } while (h > hdr_end); 1828 1829 /* we need to provide authentication */ 1830 if (conn->err == HTTP_NEED_AUTH || 1831 conn->err == HTTP_NEED_PROXY_AUTH) { 1832 e = conn->err; 1833 if ((conn->err == HTTP_NEED_AUTH && 1834 !server_challenges.valid) || 1835 (conn->err == HTTP_NEED_PROXY_AUTH && 1836 !proxy_challenges.valid)) { 1837 /* 401/7 but no www/proxy-authenticate ?? */ 1838 DEBUG(fprintf(stderr, "401/7 and no auth header\n")); 1839 goto ouch; 1840 } 1841 fetch_close(conn); 1842 conn = NULL; 1843 continue; 1844 } 1845 1846 /* requested range not satisfiable */ 1847 if (conn->err == HTTP_BAD_RANGE) { 1848 if (url->offset == size && url->length == 0) { 1849 /* asked for 0 bytes; fake it */ 1850 offset = url->offset; 1851 clength = -1; 1852 conn->err = HTTP_OK; 1853 break; 1854 } else { 1855 http_seterr(conn->err); 1856 goto ouch; 1857 } 1858 } 1859 1860 /* we have a hit or an error */ 1861 if (conn->err == HTTP_OK 1862 || conn->err == HTTP_NOT_MODIFIED 1863 || conn->err == HTTP_PARTIAL 1864 || HTTP_ERROR(conn->err)) 1865 break; 1866 1867 /* all other cases: we got a redirect */ 1868 e = conn->err; 1869 clean_http_auth_challenges(&server_challenges); 1870 fetch_close(conn); 1871 conn = NULL; 1872 if (!new) { 1873 DEBUG(fprintf(stderr, "redirect with no new location\n")); 1874 break; 1875 } 1876 if (url != URL) 1877 fetchFreeURL(url); 1878 url = new; 1879 } while (++i < n); 1880 1881 /* we failed, or ran out of retries */ 1882 if (conn == NULL) { 1883 http_seterr(e); 1884 goto ouch; 1885 } 1886 1887 DEBUG(fprintf(stderr, "offset %lld, length %lld," 1888 " size %lld, clength %lld\n", 1889 (long long)offset, (long long)length, 1890 (long long)size, (long long)clength)); 1891 1892 if (conn->err == HTTP_NOT_MODIFIED) { 1893 http_seterr(HTTP_NOT_MODIFIED); 1894 return (NULL); 1895 } 1896 1897 /* check for inconsistencies */ 1898 if (clength != -1 && length != -1 && clength != length) { 1899 http_seterr(HTTP_PROTOCOL_ERROR); 1900 goto ouch; 1901 } 1902 if (clength == -1) 1903 clength = length; 1904 if (clength != -1) 1905 length = offset + clength; 1906 if (length != -1 && size != -1 && length != size) { 1907 http_seterr(HTTP_PROTOCOL_ERROR); 1908 goto ouch; 1909 } 1910 if (size == -1) 1911 size = length; 1912 1913 /* fill in stats */ 1914 if (us) { 1915 us->size = size; 1916 us->atime = us->mtime = mtime; 1917 } 1918 1919 /* too far? */ 1920 if (URL->offset > 0 && offset > URL->offset) { 1921 http_seterr(HTTP_PROTOCOL_ERROR); 1922 goto ouch; 1923 } 1924 1925 /* report back real offset and size */ 1926 URL->offset = offset; 1927 URL->length = clength; 1928 1929 /* wrap it up in a FILE */ 1930 if ((f = http_funopen(conn, chunked)) == NULL) { 1931 fetch_syserr(); 1932 goto ouch; 1933 } 1934 1935 if (url != URL) 1936 fetchFreeURL(url); 1937 if (purl) 1938 fetchFreeURL(purl); 1939 1940 if (HTTP_ERROR(conn->err)) { 1941 http_print_html(stderr, f); 1942 fclose(f); 1943 f = NULL; 1944 } 1945 clean_http_headerbuf(&headerbuf); 1946 clean_http_auth_challenges(&server_challenges); 1947 clean_http_auth_challenges(&proxy_challenges); 1948 return (f); 1949 1950ouch: 1951 if (url != URL) 1952 fetchFreeURL(url); 1953 if (purl) 1954 fetchFreeURL(purl); 1955 if (conn != NULL) 1956 fetch_close(conn); 1957 clean_http_headerbuf(&headerbuf); 1958 clean_http_auth_challenges(&server_challenges); 1959 clean_http_auth_challenges(&proxy_challenges); 1960 return (NULL); 1961} 1962 1963 1964/***************************************************************************** 1965 * Entry points 1966 */ 1967 1968/* 1969 * Retrieve and stat a file by HTTP 1970 */ 1971FILE * 1972fetchXGetHTTP(struct url *URL, struct url_stat *us, const char *flags) 1973{ 1974 return (http_request(URL, "GET", us, http_get_proxy(URL, flags), flags)); 1975} 1976 1977/* 1978 * Retrieve a file by HTTP 1979 */ 1980FILE * 1981fetchGetHTTP(struct url *URL, const char *flags) 1982{ 1983 return (fetchXGetHTTP(URL, NULL, flags)); 1984} 1985 1986/* 1987 * Store a file by HTTP 1988 */ 1989FILE * 1990fetchPutHTTP(struct url *URL __unused, const char *flags __unused) 1991{ 1992 warnx("fetchPutHTTP(): not implemented"); 1993 return (NULL); 1994} 1995 1996/* 1997 * Get an HTTP document's metadata 1998 */ 1999int 2000fetchStatHTTP(struct url *URL, struct url_stat *us, const char *flags) 2001{ 2002 FILE *f; 2003 2004 f = http_request(URL, "HEAD", us, http_get_proxy(URL, flags), flags); 2005 if (f == NULL) 2006 return (-1); 2007 fclose(f); 2008 return (0); 2009} 2010 2011/* 2012 * List a directory 2013 */ 2014struct url_ent * 2015fetchListHTTP(struct url *url __unused, const char *flags __unused) 2016{ 2017 warnx("fetchListHTTP(): not implemented"); 2018 return (NULL); 2019} 2020