1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 2000-2014 Dag-Erling Smørgrav 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer 12 * in this position and unchanged. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. The name of the author may not be used to endorse or promote products 17 * derived from this software without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #include <sys/cdefs.h> 32 __FBSDID("$FreeBSD$"); 33 34 /* 35 * The following copyright applies to the base64 code: 36 * 37 *- 38 * Copyright 1997 Massachusetts Institute of Technology 39 * 40 * Permission to use, copy, modify, and distribute this software and 41 * its documentation for any purpose and without fee is hereby 42 * granted, provided that both the above copyright notice and this 43 * permission notice appear in all copies, that both the above 44 * copyright notice and this permission notice appear in all 45 * supporting documentation, and that the name of M.I.T. not be used 46 * in advertising or publicity pertaining to distribution of the 47 * software without specific, written prior permission. M.I.T. makes 48 * no representations about the suitability of this software for any 49 * purpose. It is provided "as is" without express or implied 50 * warranty. 51 * 52 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS 53 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE, 54 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 55 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT 56 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 57 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 58 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 59 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 60 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 61 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 62 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 63 * SUCH DAMAGE. 64 */ 65 66 #include <sys/param.h> 67 #include <sys/socket.h> 68 #include <sys/time.h> 69 70 #include <ctype.h> 71 #include <err.h> 72 #include <errno.h> 73 #include <locale.h> 74 #include <netdb.h> 75 #include <stdarg.h> 76 #include <stdbool.h> 77 #include <stdio.h> 78 #include <stdlib.h> 79 #include <string.h> 80 #include <time.h> 81 #include <unistd.h> 82 83 #ifdef WITH_SSL 84 #include <openssl/md5.h> 85 #define MD5Init(c) MD5_Init(c) 86 #define MD5Update(c, data, len) MD5_Update(c, data, len) 87 #define MD5Final(md, c) MD5_Final(md, c) 88 #else 89 #include <md5.h> 90 #endif 91 92 #include <netinet/in.h> 93 #include <netinet/tcp.h> 94 95 #include "fetch.h" 96 #include "common.h" 97 #include "httperr.h" 98 99 /* Maximum number of redirects to follow */ 100 #define MAX_REDIRECT 20 101 102 /* Symbolic names for reply codes we care about */ 103 #define HTTP_OK 200 104 #define HTTP_PARTIAL 206 105 #define HTTP_MOVED_PERM 301 106 #define HTTP_MOVED_TEMP 302 107 #define HTTP_SEE_OTHER 303 108 #define HTTP_NOT_MODIFIED 304 109 #define HTTP_USE_PROXY 305 110 #define HTTP_TEMP_REDIRECT 307 111 #define HTTP_PERM_REDIRECT 308 112 #define HTTP_NEED_AUTH 401 113 #define HTTP_NEED_PROXY_AUTH 407 114 #define HTTP_BAD_RANGE 416 115 #define HTTP_PROTOCOL_ERROR 999 116 117 #define HTTP_REDIRECT(xyz) ((xyz) == HTTP_MOVED_PERM \ 118 || (xyz) == HTTP_MOVED_TEMP \ 119 || (xyz) == HTTP_TEMP_REDIRECT \ 120 || (xyz) == HTTP_PERM_REDIRECT \ 121 || (xyz) == HTTP_USE_PROXY \ 122 || (xyz) == HTTP_SEE_OTHER) 123 124 #define HTTP_ERROR(xyz) ((xyz) >= 400 && (xyz) <= 599) 125 126 127 /***************************************************************************** 128 * I/O functions for decoding chunked streams 129 */ 130 131 struct httpio 132 { 133 conn_t *conn; /* connection */ 134 int chunked; /* chunked mode */ 135 char *buf; /* chunk buffer */ 136 size_t bufsize; /* size of chunk buffer */ 137 size_t buflen; /* amount of data currently in buffer */ 138 size_t bufpos; /* current read offset in buffer */ 139 int eof; /* end-of-file flag */ 140 int error; /* error flag */ 141 size_t chunksize; /* remaining size of current chunk */ 142 #ifndef NDEBUG 143 size_t total; 144 #endif 145 }; 146 147 /* 148 * Get next chunk header 149 */ 150 static int 151 http_new_chunk(struct httpio *io) 152 { 153 char *p; 154 155 if (fetch_getln(io->conn) == -1) 156 return (-1); 157 158 if (io->conn->buflen < 2 || !isxdigit((unsigned char)*io->conn->buf)) 159 return (-1); 160 161 for (p = io->conn->buf; *p && !isspace((unsigned char)*p); ++p) { 162 if (*p == ';') 163 break; 164 if (!isxdigit((unsigned char)*p)) 165 return (-1); 166 if (isdigit((unsigned char)*p)) { 167 io->chunksize = io->chunksize * 16 + 168 *p - '0'; 169 } else { 170 io->chunksize = io->chunksize * 16 + 171 10 + tolower((unsigned char)*p) - 'a'; 172 } 173 } 174 175 #ifndef NDEBUG 176 if (fetchDebug) { 177 io->total += io->chunksize; 178 if (io->chunksize == 0) 179 fprintf(stderr, "%s(): end of last chunk\n", __func__); 180 else 181 fprintf(stderr, "%s(): new chunk: %lu (%lu)\n", 182 __func__, (unsigned long)io->chunksize, 183 (unsigned long)io->total); 184 } 185 #endif 186 187 return (io->chunksize); 188 } 189 190 /* 191 * Grow the input buffer to at least len bytes 192 */ 193 static inline int 194 http_growbuf(struct httpio *io, size_t len) 195 { 196 char *tmp; 197 198 if (io->bufsize >= len) 199 return (0); 200 201 if ((tmp = realloc(io->buf, len)) == NULL) 202 return (-1); 203 io->buf = tmp; 204 io->bufsize = len; 205 return (0); 206 } 207 208 /* 209 * Fill the input buffer, do chunk decoding on the fly 210 */ 211 static ssize_t 212 http_fillbuf(struct httpio *io, size_t len) 213 { 214 ssize_t nbytes; 215 char ch; 216 217 if (io->error) 218 return (-1); 219 if (io->eof) 220 return (0); 221 222 /* not chunked: just fetch the requested amount */ 223 if (io->chunked == 0) { 224 if (http_growbuf(io, len) == -1) 225 return (-1); 226 if ((nbytes = fetch_read(io->conn, io->buf, len)) == -1) { 227 io->error = errno; 228 return (-1); 229 } 230 io->buflen = nbytes; 231 io->bufpos = 0; 232 return (io->buflen); 233 } 234 235 /* chunked, but we ran out: get the next chunk header */ 236 if (io->chunksize == 0) { 237 switch (http_new_chunk(io)) { 238 case -1: 239 io->error = EPROTO; 240 return (-1); 241 case 0: 242 io->eof = 1; 243 return (0); 244 } 245 } 246 247 /* fetch the requested amount, but no more than the current chunk */ 248 if (len > io->chunksize) 249 len = io->chunksize; 250 if (http_growbuf(io, len) == -1) 251 return (-1); 252 if ((nbytes = fetch_read(io->conn, io->buf, len)) == -1) { 253 io->error = errno; 254 return (-1); 255 } 256 io->bufpos = 0; 257 io->buflen = nbytes; 258 io->chunksize -= nbytes; 259 260 if (io->chunksize == 0) { 261 if (fetch_read(io->conn, &ch, 1) != 1 || ch != '\r' || 262 fetch_read(io->conn, &ch, 1) != 1 || ch != '\n') 263 return (-1); 264 } 265 266 return (io->buflen); 267 } 268 269 /* 270 * Read function 271 */ 272 static int 273 http_readfn(void *v, char *buf, int len) 274 { 275 struct httpio *io = (struct httpio *)v; 276 int rlen; 277 278 if (io->error) 279 return (-1); 280 if (io->eof) 281 return (0); 282 283 /* empty buffer */ 284 if (!io->buf || io->bufpos == io->buflen) { 285 if ((rlen = http_fillbuf(io, len)) < 0) { 286 if ((errno = io->error) == EINTR) 287 io->error = 0; 288 return (-1); 289 } else if (rlen == 0) { 290 return (0); 291 } 292 } 293 294 rlen = io->buflen - io->bufpos; 295 if (len < rlen) 296 rlen = len; 297 memcpy(buf, io->buf + io->bufpos, rlen); 298 io->bufpos += rlen; 299 return (rlen); 300 } 301 302 /* 303 * Write function 304 */ 305 static int 306 http_writefn(void *v, const char *buf, int len) 307 { 308 struct httpio *io = (struct httpio *)v; 309 310 return (fetch_write(io->conn, buf, len)); 311 } 312 313 /* 314 * Close function 315 */ 316 static int 317 http_closefn(void *v) 318 { 319 struct httpio *io = (struct httpio *)v; 320 int r; 321 322 r = fetch_close(io->conn); 323 if (io->buf) 324 free(io->buf); 325 free(io); 326 return (r); 327 } 328 329 /* 330 * Wrap a file descriptor up 331 */ 332 static FILE * 333 http_funopen(conn_t *conn, int chunked) 334 { 335 struct httpio *io; 336 FILE *f; 337 338 if ((io = calloc(1, sizeof(*io))) == NULL) { 339 fetch_syserr(); 340 return (NULL); 341 } 342 io->conn = conn; 343 io->chunked = chunked; 344 f = funopen(io, http_readfn, http_writefn, NULL, http_closefn); 345 if (f == NULL) { 346 fetch_syserr(); 347 free(io); 348 return (NULL); 349 } 350 return (f); 351 } 352 353 354 /***************************************************************************** 355 * Helper functions for talking to the server and parsing its replies 356 */ 357 358 /* Header types */ 359 typedef enum { 360 hdr_syserror = -2, 361 hdr_error = -1, 362 hdr_end = 0, 363 hdr_unknown = 1, 364 hdr_content_length, 365 hdr_content_range, 366 hdr_last_modified, 367 hdr_location, 368 hdr_transfer_encoding, 369 hdr_www_authenticate, 370 hdr_proxy_authenticate, 371 } hdr_t; 372 373 /* Names of interesting headers */ 374 static struct { 375 hdr_t num; 376 const char *name; 377 } hdr_names[] = { 378 { hdr_content_length, "Content-Length" }, 379 { hdr_content_range, "Content-Range" }, 380 { hdr_last_modified, "Last-Modified" }, 381 { hdr_location, "Location" }, 382 { hdr_transfer_encoding, "Transfer-Encoding" }, 383 { hdr_www_authenticate, "WWW-Authenticate" }, 384 { hdr_proxy_authenticate, "Proxy-Authenticate" }, 385 { hdr_unknown, NULL }, 386 }; 387 388 /* 389 * Send a formatted line; optionally echo to terminal 390 */ 391 static int 392 http_cmd(conn_t *conn, const char *fmt, ...) 393 { 394 va_list ap; 395 size_t len; 396 char *msg; 397 int r; 398 399 va_start(ap, fmt); 400 len = vasprintf(&msg, fmt, ap); 401 va_end(ap); 402 403 if (msg == NULL) { 404 errno = ENOMEM; 405 fetch_syserr(); 406 return (-1); 407 } 408 409 r = fetch_putln(conn, msg, len); 410 free(msg); 411 412 if (r == -1) { 413 fetch_syserr(); 414 return (-1); 415 } 416 417 return (0); 418 } 419 420 /* 421 * Get and parse status line 422 */ 423 static int 424 http_get_reply(conn_t *conn) 425 { 426 char *p; 427 428 if (fetch_getln(conn) == -1) 429 return (-1); 430 /* 431 * A valid status line looks like "HTTP/m.n xyz reason" where m 432 * and n are the major and minor protocol version numbers and xyz 433 * is the reply code. 434 * Unfortunately, there are servers out there (NCSA 1.5.1, to name 435 * just one) that do not send a version number, so we can't rely 436 * on finding one, but if we do, insist on it being 1.0 or 1.1. 437 * We don't care about the reason phrase. 438 */ 439 if (strncmp(conn->buf, "HTTP", 4) != 0) 440 return (HTTP_PROTOCOL_ERROR); 441 p = conn->buf + 4; 442 if (*p == '/') { 443 if (p[1] != '1' || p[2] != '.' || (p[3] != '0' && p[3] != '1')) 444 return (HTTP_PROTOCOL_ERROR); 445 p += 4; 446 } 447 if (*p != ' ' || 448 !isdigit((unsigned char)p[1]) || 449 !isdigit((unsigned char)p[2]) || 450 !isdigit((unsigned char)p[3])) 451 return (HTTP_PROTOCOL_ERROR); 452 453 conn->err = (p[1] - '0') * 100 + (p[2] - '0') * 10 + (p[3] - '0'); 454 return (conn->err); 455 } 456 457 /* 458 * Check a header; if the type matches the given string, return a pointer 459 * to the beginning of the value. 460 */ 461 static const char * 462 http_match(const char *str, const char *hdr) 463 { 464 while (*str && *hdr && 465 tolower((unsigned char)*str++) == tolower((unsigned char)*hdr++)) 466 /* nothing */; 467 if (*str || *hdr != ':') 468 return (NULL); 469 while (*hdr && isspace((unsigned char)*++hdr)) 470 /* nothing */; 471 return (hdr); 472 } 473 474 475 /* 476 * Get the next header and return the appropriate symbolic code. We 477 * need to read one line ahead for checking for a continuation line 478 * belonging to the current header (continuation lines start with 479 * white space). 480 * 481 * We get called with a fresh line already in the conn buffer, either 482 * from the previous http_next_header() invocation, or, the first 483 * time, from a fetch_getln() performed by our caller. 484 * 485 * This stops when we encounter an empty line (we dont read beyond the header 486 * area). 487 * 488 * Note that the "headerbuf" is just a place to return the result. Its 489 * contents are not used for the next call. This means that no cleanup 490 * is needed when ie doing another connection, just call the cleanup when 491 * fully done to deallocate memory. 492 */ 493 494 /* Limit the max number of continuation lines to some reasonable value */ 495 #define HTTP_MAX_CONT_LINES 10 496 497 /* Place into which to build a header from one or several lines */ 498 typedef struct { 499 char *buf; /* buffer */ 500 size_t bufsize; /* buffer size */ 501 size_t buflen; /* length of buffer contents */ 502 } http_headerbuf_t; 503 504 static void 505 init_http_headerbuf(http_headerbuf_t *buf) 506 { 507 buf->buf = NULL; 508 buf->bufsize = 0; 509 buf->buflen = 0; 510 } 511 512 static void 513 clean_http_headerbuf(http_headerbuf_t *buf) 514 { 515 if (buf->buf) 516 free(buf->buf); 517 init_http_headerbuf(buf); 518 } 519 520 /* Remove whitespace at the end of the buffer */ 521 static void 522 http_conn_trimright(conn_t *conn) 523 { 524 while (conn->buflen && 525 isspace((unsigned char)conn->buf[conn->buflen - 1])) 526 conn->buflen--; 527 conn->buf[conn->buflen] = '\0'; 528 } 529 530 static hdr_t 531 http_next_header(conn_t *conn, http_headerbuf_t *hbuf, const char **p) 532 { 533 unsigned int i, len; 534 535 /* 536 * Have to do the stripping here because of the first line. So 537 * it's done twice for the subsequent lines. No big deal 538 */ 539 http_conn_trimright(conn); 540 if (conn->buflen == 0) 541 return (hdr_end); 542 543 /* Copy the line to the headerbuf */ 544 if (hbuf->bufsize < conn->buflen + 1) { 545 if ((hbuf->buf = realloc(hbuf->buf, conn->buflen + 1)) == NULL) 546 return (hdr_syserror); 547 hbuf->bufsize = conn->buflen + 1; 548 } 549 strcpy(hbuf->buf, conn->buf); 550 hbuf->buflen = conn->buflen; 551 552 /* 553 * Fetch possible continuation lines. Stop at 1st non-continuation 554 * and leave it in the conn buffer 555 */ 556 for (i = 0; i < HTTP_MAX_CONT_LINES; i++) { 557 if (fetch_getln(conn) == -1) 558 return (hdr_syserror); 559 560 /* 561 * Note: we carry on the idea from the previous version 562 * that a pure whitespace line is equivalent to an empty 563 * one (so it's not continuation and will be handled when 564 * we are called next) 565 */ 566 http_conn_trimright(conn); 567 if (conn->buf[0] != ' ' && conn->buf[0] != "\t"[0]) 568 break; 569 570 /* Got a continuation line. Concatenate to previous */ 571 len = hbuf->buflen + conn->buflen; 572 if (hbuf->bufsize < len + 1) { 573 len *= 2; 574 if ((hbuf->buf = realloc(hbuf->buf, len + 1)) == NULL) 575 return (hdr_syserror); 576 hbuf->bufsize = len + 1; 577 } 578 strcpy(hbuf->buf + hbuf->buflen, conn->buf); 579 hbuf->buflen += conn->buflen; 580 } 581 582 /* 583 * We could check for malformed headers but we don't really care. 584 * A valid header starts with a token immediately followed by a 585 * colon; a token is any sequence of non-control, non-whitespace 586 * characters except "()<>@,;:\\\"{}". 587 */ 588 for (i = 0; hdr_names[i].num != hdr_unknown; i++) 589 if ((*p = http_match(hdr_names[i].name, hbuf->buf)) != NULL) 590 return (hdr_names[i].num); 591 592 return (hdr_unknown); 593 } 594 595 /************************** 596 * [Proxy-]Authenticate header parsing 597 */ 598 599 /* 600 * Read doublequote-delimited string into output buffer obuf (allocated 601 * by caller, whose responsibility it is to ensure that it's big enough) 602 * cp points to the first char after the initial '"' 603 * Handles \ quoting 604 * Returns pointer to the first char after the terminating double quote, or 605 * NULL for error. 606 */ 607 static const char * 608 http_parse_headerstring(const char *cp, char *obuf) 609 { 610 for (;;) { 611 switch (*cp) { 612 case 0: /* Unterminated string */ 613 *obuf = 0; 614 return (NULL); 615 case '"': /* Ending quote */ 616 *obuf = 0; 617 return (++cp); 618 case '\\': 619 if (*++cp == 0) { 620 *obuf = 0; 621 return (NULL); 622 } 623 /* FALLTHROUGH */ 624 default: 625 *obuf++ = *cp++; 626 } 627 } 628 } 629 630 /* Http auth challenge schemes */ 631 typedef enum {HTTPAS_UNKNOWN, HTTPAS_BASIC,HTTPAS_DIGEST} http_auth_schemes_t; 632 633 /* Data holder for a Basic or Digest challenge. */ 634 typedef struct { 635 http_auth_schemes_t scheme; 636 char *realm; 637 char *qop; 638 char *nonce; 639 char *opaque; 640 char *algo; 641 int stale; 642 int nc; /* Nonce count */ 643 } http_auth_challenge_t; 644 645 static void 646 init_http_auth_challenge(http_auth_challenge_t *b) 647 { 648 b->scheme = HTTPAS_UNKNOWN; 649 b->realm = b->qop = b->nonce = b->opaque = b->algo = NULL; 650 b->stale = b->nc = 0; 651 } 652 653 static void 654 clean_http_auth_challenge(http_auth_challenge_t *b) 655 { 656 if (b->realm) 657 free(b->realm); 658 if (b->qop) 659 free(b->qop); 660 if (b->nonce) 661 free(b->nonce); 662 if (b->opaque) 663 free(b->opaque); 664 if (b->algo) 665 free(b->algo); 666 init_http_auth_challenge(b); 667 } 668 669 /* Data holder for an array of challenges offered in an http response. */ 670 #define MAX_CHALLENGES 10 671 typedef struct { 672 http_auth_challenge_t *challenges[MAX_CHALLENGES]; 673 int count; /* Number of parsed challenges in the array */ 674 int valid; /* We did parse an authenticate header */ 675 } http_auth_challenges_t; 676 677 static void 678 init_http_auth_challenges(http_auth_challenges_t *cs) 679 { 680 int i; 681 for (i = 0; i < MAX_CHALLENGES; i++) 682 cs->challenges[i] = NULL; 683 cs->count = cs->valid = 0; 684 } 685 686 static void 687 clean_http_auth_challenges(http_auth_challenges_t *cs) 688 { 689 int i; 690 /* We rely on non-zero pointers being allocated, not on the count */ 691 for (i = 0; i < MAX_CHALLENGES; i++) { 692 if (cs->challenges[i] != NULL) { 693 clean_http_auth_challenge(cs->challenges[i]); 694 free(cs->challenges[i]); 695 } 696 } 697 init_http_auth_challenges(cs); 698 } 699 700 /* 701 * Enumeration for lexical elements. Separators will be returned as their own 702 * ascii value 703 */ 704 typedef enum {HTTPHL_WORD=256, HTTPHL_STRING=257, HTTPHL_END=258, 705 HTTPHL_ERROR = 259} http_header_lex_t; 706 707 /* 708 * Determine what kind of token comes next and return possible value 709 * in buf, which is supposed to have been allocated big enough by 710 * caller. Advance input pointer and return element type. 711 */ 712 static int 713 http_header_lex(const char **cpp, char *buf) 714 { 715 size_t l; 716 /* Eat initial whitespace */ 717 *cpp += strspn(*cpp, " \t"); 718 if (**cpp == 0) 719 return (HTTPHL_END); 720 721 /* Separator ? */ 722 if (**cpp == ',' || **cpp == '=') 723 return (*((*cpp)++)); 724 725 /* String ? */ 726 if (**cpp == '"') { 727 *cpp = http_parse_headerstring(++*cpp, buf); 728 if (*cpp == NULL) 729 return (HTTPHL_ERROR); 730 return (HTTPHL_STRING); 731 } 732 733 /* Read other token, until separator or whitespace */ 734 l = strcspn(*cpp, " \t,="); 735 memcpy(buf, *cpp, l); 736 buf[l] = 0; 737 *cpp += l; 738 return (HTTPHL_WORD); 739 } 740 741 /* 742 * Read challenges from http xxx-authenticate header and accumulate them 743 * in the challenges list structure. 744 * 745 * Headers with multiple challenges are specified by rfc2617, but 746 * servers (ie: squid) often send them in separate headers instead, 747 * which in turn is forbidden by the http spec (multiple headers with 748 * the same name are only allowed for pure comma-separated lists, see 749 * rfc2616 sec 4.2). 750 * 751 * We support both approaches anyway 752 */ 753 static int 754 http_parse_authenticate(const char *cp, http_auth_challenges_t *cs) 755 { 756 int ret = -1; 757 http_header_lex_t lex; 758 char *key = malloc(strlen(cp) + 1); 759 char *value = malloc(strlen(cp) + 1); 760 char *buf = malloc(strlen(cp) + 1); 761 762 if (key == NULL || value == NULL || buf == NULL) { 763 fetch_syserr(); 764 goto out; 765 } 766 767 /* In any case we've seen the header and we set the valid bit */ 768 cs->valid = 1; 769 770 /* Need word first */ 771 lex = http_header_lex(&cp, key); 772 if (lex != HTTPHL_WORD) 773 goto out; 774 775 /* Loop on challenges */ 776 for (; cs->count < MAX_CHALLENGES; cs->count++) { 777 cs->challenges[cs->count] = 778 malloc(sizeof(http_auth_challenge_t)); 779 if (cs->challenges[cs->count] == NULL) { 780 fetch_syserr(); 781 goto out; 782 } 783 init_http_auth_challenge(cs->challenges[cs->count]); 784 if (strcasecmp(key, "basic") == 0) { 785 cs->challenges[cs->count]->scheme = HTTPAS_BASIC; 786 } else if (strcasecmp(key, "digest") == 0) { 787 cs->challenges[cs->count]->scheme = HTTPAS_DIGEST; 788 } else { 789 cs->challenges[cs->count]->scheme = HTTPAS_UNKNOWN; 790 /* 791 * Continue parsing as basic or digest may 792 * follow, and the syntax is the same for 793 * all. We'll just ignore this one when 794 * looking at the list 795 */ 796 } 797 798 /* Loop on attributes */ 799 for (;;) { 800 /* Key */ 801 lex = http_header_lex(&cp, key); 802 if (lex != HTTPHL_WORD) 803 goto out; 804 805 /* Equal sign */ 806 lex = http_header_lex(&cp, buf); 807 if (lex != '=') 808 goto out; 809 810 /* Value */ 811 lex = http_header_lex(&cp, value); 812 if (lex != HTTPHL_WORD && lex != HTTPHL_STRING) 813 goto out; 814 815 if (strcasecmp(key, "realm") == 0) { 816 cs->challenges[cs->count]->realm = 817 strdup(value); 818 } else if (strcasecmp(key, "qop") == 0) { 819 cs->challenges[cs->count]->qop = 820 strdup(value); 821 } else if (strcasecmp(key, "nonce") == 0) { 822 cs->challenges[cs->count]->nonce = 823 strdup(value); 824 } else if (strcasecmp(key, "opaque") == 0) { 825 cs->challenges[cs->count]->opaque = 826 strdup(value); 827 } else if (strcasecmp(key, "algorithm") == 0) { 828 cs->challenges[cs->count]->algo = 829 strdup(value); 830 } else if (strcasecmp(key, "stale") == 0) { 831 cs->challenges[cs->count]->stale = 832 strcasecmp(value, "no"); 833 } else { 834 /* ignore unknown attributes */ 835 } 836 837 /* Comma or Next challenge or End */ 838 lex = http_header_lex(&cp, key); 839 /* 840 * If we get a word here, this is the beginning of the 841 * next challenge. Break the attributes loop 842 */ 843 if (lex == HTTPHL_WORD) 844 break; 845 846 if (lex == HTTPHL_END) { 847 /* End while looking for ',' is normal exit */ 848 cs->count++; 849 ret = 0; 850 goto out; 851 } 852 /* Anything else is an error */ 853 if (lex != ',') 854 goto out; 855 856 } /* End attributes loop */ 857 } /* End challenge loop */ 858 859 /* 860 * Challenges max count exceeded. This really can't happen 861 * with normal data, something's fishy -> error 862 */ 863 864 out: 865 if (key) 866 free(key); 867 if (value) 868 free(value); 869 if (buf) 870 free(buf); 871 return (ret); 872 } 873 874 875 /* 876 * Parse a last-modified header 877 */ 878 static int 879 http_parse_mtime(const char *p, time_t *mtime) 880 { 881 char locale[64], *r; 882 struct tm tm; 883 884 strlcpy(locale, setlocale(LC_TIME, NULL), sizeof(locale)); 885 setlocale(LC_TIME, "C"); 886 r = strptime(p, "%a, %d %b %Y %H:%M:%S GMT", &tm); 887 /* 888 * Some proxies use UTC in response, but it should still be 889 * parsed. RFC2616 states GMT and UTC are exactly equal for HTTP. 890 */ 891 if (r == NULL) 892 r = strptime(p, "%a, %d %b %Y %H:%M:%S UTC", &tm); 893 /* XXX should add support for date-2 and date-3 */ 894 setlocale(LC_TIME, locale); 895 if (r == NULL) 896 return (-1); 897 DEBUGF("last modified: [%04d-%02d-%02d %02d:%02d:%02d]\n", 898 tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, 899 tm.tm_hour, tm.tm_min, tm.tm_sec); 900 *mtime = timegm(&tm); 901 return (0); 902 } 903 904 /* 905 * Parse a content-length header 906 */ 907 static int 908 http_parse_length(const char *p, off_t *length) 909 { 910 off_t len; 911 912 for (len = 0; *p && isdigit((unsigned char)*p); ++p) 913 len = len * 10 + (*p - '0'); 914 if (*p) 915 return (-1); 916 DEBUGF("content length: [%lld]\n", (long long)len); 917 *length = len; 918 return (0); 919 } 920 921 /* 922 * Parse a content-range header 923 */ 924 static int 925 http_parse_range(const char *p, off_t *offset, off_t *length, off_t *size) 926 { 927 off_t first, last, len; 928 929 if (strncasecmp(p, "bytes ", 6) != 0) 930 return (-1); 931 p += 6; 932 if (*p == '*') { 933 first = last = -1; 934 ++p; 935 } else { 936 for (first = 0; *p && isdigit((unsigned char)*p); ++p) 937 first = first * 10 + *p - '0'; 938 if (*p != '-') 939 return (-1); 940 for (last = 0, ++p; *p && isdigit((unsigned char)*p); ++p) 941 last = last * 10 + *p - '0'; 942 } 943 if (first > last || *p != '/') 944 return (-1); 945 for (len = 0, ++p; *p && isdigit((unsigned char)*p); ++p) 946 len = len * 10 + *p - '0'; 947 if (*p || len < last - first + 1) 948 return (-1); 949 if (first == -1) { 950 DEBUGF("content range: [*/%lld]\n", (long long)len); 951 *length = 0; 952 } else { 953 DEBUGF("content range: [%lld-%lld/%lld]\n", 954 (long long)first, (long long)last, (long long)len); 955 *length = last - first + 1; 956 } 957 *offset = first; 958 *size = len; 959 return (0); 960 } 961 962 963 /***************************************************************************** 964 * Helper functions for authorization 965 */ 966 967 /* 968 * Base64 encoding 969 */ 970 static char * 971 http_base64(const char *src) 972 { 973 static const char base64[] = 974 "ABCDEFGHIJKLMNOPQRSTUVWXYZ" 975 "abcdefghijklmnopqrstuvwxyz" 976 "0123456789+/"; 977 char *str, *dst; 978 size_t l; 979 int t; 980 981 l = strlen(src); 982 if ((str = malloc(((l + 2) / 3) * 4 + 1)) == NULL) 983 return (NULL); 984 dst = str; 985 986 while (l >= 3) { 987 t = (src[0] << 16) | (src[1] << 8) | src[2]; 988 dst[0] = base64[(t >> 18) & 0x3f]; 989 dst[1] = base64[(t >> 12) & 0x3f]; 990 dst[2] = base64[(t >> 6) & 0x3f]; 991 dst[3] = base64[(t >> 0) & 0x3f]; 992 src += 3; l -= 3; 993 dst += 4; 994 } 995 996 switch (l) { 997 case 2: 998 t = (src[0] << 16) | (src[1] << 8); 999 dst[0] = base64[(t >> 18) & 0x3f]; 1000 dst[1] = base64[(t >> 12) & 0x3f]; 1001 dst[2] = base64[(t >> 6) & 0x3f]; 1002 dst[3] = '='; 1003 dst += 4; 1004 break; 1005 case 1: 1006 t = src[0] << 16; 1007 dst[0] = base64[(t >> 18) & 0x3f]; 1008 dst[1] = base64[(t >> 12) & 0x3f]; 1009 dst[2] = dst[3] = '='; 1010 dst += 4; 1011 break; 1012 case 0: 1013 break; 1014 } 1015 1016 *dst = 0; 1017 return (str); 1018 } 1019 1020 1021 /* 1022 * Extract authorization parameters from environment value. 1023 * The value is like scheme:realm:user:pass 1024 */ 1025 typedef struct { 1026 char *scheme; 1027 char *realm; 1028 char *user; 1029 char *password; 1030 } http_auth_params_t; 1031 1032 static void 1033 init_http_auth_params(http_auth_params_t *s) 1034 { 1035 s->scheme = s->realm = s->user = s->password = NULL; 1036 } 1037 1038 static void 1039 clean_http_auth_params(http_auth_params_t *s) 1040 { 1041 if (s->scheme) 1042 free(s->scheme); 1043 if (s->realm) 1044 free(s->realm); 1045 if (s->user) 1046 free(s->user); 1047 if (s->password) 1048 free(s->password); 1049 init_http_auth_params(s); 1050 } 1051 1052 static int 1053 http_authfromenv(const char *p, http_auth_params_t *parms) 1054 { 1055 int ret = -1; 1056 char *v, *ve; 1057 char *str = strdup(p); 1058 1059 if (str == NULL) { 1060 fetch_syserr(); 1061 return (-1); 1062 } 1063 v = str; 1064 1065 if ((ve = strchr(v, ':')) == NULL) 1066 goto out; 1067 1068 *ve = 0; 1069 if ((parms->scheme = strdup(v)) == NULL) { 1070 fetch_syserr(); 1071 goto out; 1072 } 1073 v = ve + 1; 1074 1075 if ((ve = strchr(v, ':')) == NULL) 1076 goto out; 1077 1078 *ve = 0; 1079 if ((parms->realm = strdup(v)) == NULL) { 1080 fetch_syserr(); 1081 goto out; 1082 } 1083 v = ve + 1; 1084 1085 if ((ve = strchr(v, ':')) == NULL) 1086 goto out; 1087 1088 *ve = 0; 1089 if ((parms->user = strdup(v)) == NULL) { 1090 fetch_syserr(); 1091 goto out; 1092 } 1093 v = ve + 1; 1094 1095 1096 if ((parms->password = strdup(v)) == NULL) { 1097 fetch_syserr(); 1098 goto out; 1099 } 1100 ret = 0; 1101 out: 1102 if (ret == -1) 1103 clean_http_auth_params(parms); 1104 if (str) 1105 free(str); 1106 return (ret); 1107 } 1108 1109 1110 /* 1111 * Digest response: the code to compute the digest is taken from the 1112 * sample implementation in RFC2616 1113 */ 1114 #define IN const 1115 #define OUT 1116 1117 #define HASHLEN 16 1118 typedef char HASH[HASHLEN]; 1119 #define HASHHEXLEN 32 1120 typedef char HASHHEX[HASHHEXLEN+1]; 1121 1122 static const char *hexchars = "0123456789abcdef"; 1123 static void 1124 CvtHex(IN HASH Bin, OUT HASHHEX Hex) 1125 { 1126 unsigned short i; 1127 unsigned char j; 1128 1129 for (i = 0; i < HASHLEN; i++) { 1130 j = (Bin[i] >> 4) & 0xf; 1131 Hex[i*2] = hexchars[j]; 1132 j = Bin[i] & 0xf; 1133 Hex[i*2+1] = hexchars[j]; 1134 } 1135 Hex[HASHHEXLEN] = '\0'; 1136 }; 1137 1138 /* calculate H(A1) as per spec */ 1139 static void 1140 DigestCalcHA1( 1141 IN char * pszAlg, 1142 IN char * pszUserName, 1143 IN char * pszRealm, 1144 IN char * pszPassword, 1145 IN char * pszNonce, 1146 IN char * pszCNonce, 1147 OUT HASHHEX SessionKey 1148 ) 1149 { 1150 MD5_CTX Md5Ctx; 1151 HASH HA1; 1152 1153 MD5Init(&Md5Ctx); 1154 MD5Update(&Md5Ctx, pszUserName, strlen(pszUserName)); 1155 MD5Update(&Md5Ctx, ":", 1); 1156 MD5Update(&Md5Ctx, pszRealm, strlen(pszRealm)); 1157 MD5Update(&Md5Ctx, ":", 1); 1158 MD5Update(&Md5Ctx, pszPassword, strlen(pszPassword)); 1159 MD5Final(HA1, &Md5Ctx); 1160 if (strcasecmp(pszAlg, "md5-sess") == 0) { 1161 1162 MD5Init(&Md5Ctx); 1163 MD5Update(&Md5Ctx, HA1, HASHLEN); 1164 MD5Update(&Md5Ctx, ":", 1); 1165 MD5Update(&Md5Ctx, pszNonce, strlen(pszNonce)); 1166 MD5Update(&Md5Ctx, ":", 1); 1167 MD5Update(&Md5Ctx, pszCNonce, strlen(pszCNonce)); 1168 MD5Final(HA1, &Md5Ctx); 1169 } 1170 CvtHex(HA1, SessionKey); 1171 } 1172 1173 /* calculate request-digest/response-digest as per HTTP Digest spec */ 1174 static void 1175 DigestCalcResponse( 1176 IN HASHHEX HA1, /* H(A1) */ 1177 IN char * pszNonce, /* nonce from server */ 1178 IN char * pszNonceCount, /* 8 hex digits */ 1179 IN char * pszCNonce, /* client nonce */ 1180 IN char * pszQop, /* qop-value: "", "auth", "auth-int" */ 1181 IN char * pszMethod, /* method from the request */ 1182 IN char * pszDigestUri, /* requested URL */ 1183 IN HASHHEX HEntity, /* H(entity body) if qop="auth-int" */ 1184 OUT HASHHEX Response /* request-digest or response-digest */ 1185 ) 1186 { 1187 #if 0 1188 DEBUGF("Calc: HA1[%s] Nonce[%s] qop[%s] method[%s] URI[%s]\n", 1189 HA1, pszNonce, pszQop, pszMethod, pszDigestUri); 1190 #endif 1191 MD5_CTX Md5Ctx; 1192 HASH HA2; 1193 HASH RespHash; 1194 HASHHEX HA2Hex; 1195 1196 // calculate H(A2) 1197 MD5Init(&Md5Ctx); 1198 MD5Update(&Md5Ctx, pszMethod, strlen(pszMethod)); 1199 MD5Update(&Md5Ctx, ":", 1); 1200 MD5Update(&Md5Ctx, pszDigestUri, strlen(pszDigestUri)); 1201 if (strcasecmp(pszQop, "auth-int") == 0) { 1202 MD5Update(&Md5Ctx, ":", 1); 1203 MD5Update(&Md5Ctx, HEntity, HASHHEXLEN); 1204 } 1205 MD5Final(HA2, &Md5Ctx); 1206 CvtHex(HA2, HA2Hex); 1207 1208 // calculate response 1209 MD5Init(&Md5Ctx); 1210 MD5Update(&Md5Ctx, HA1, HASHHEXLEN); 1211 MD5Update(&Md5Ctx, ":", 1); 1212 MD5Update(&Md5Ctx, pszNonce, strlen(pszNonce)); 1213 MD5Update(&Md5Ctx, ":", 1); 1214 if (*pszQop) { 1215 MD5Update(&Md5Ctx, pszNonceCount, strlen(pszNonceCount)); 1216 MD5Update(&Md5Ctx, ":", 1); 1217 MD5Update(&Md5Ctx, pszCNonce, strlen(pszCNonce)); 1218 MD5Update(&Md5Ctx, ":", 1); 1219 MD5Update(&Md5Ctx, pszQop, strlen(pszQop)); 1220 MD5Update(&Md5Ctx, ":", 1); 1221 } 1222 MD5Update(&Md5Ctx, HA2Hex, HASHHEXLEN); 1223 MD5Final(RespHash, &Md5Ctx); 1224 CvtHex(RespHash, Response); 1225 } 1226 1227 /* 1228 * Generate/Send a Digest authorization header 1229 * This looks like: [Proxy-]Authorization: credentials 1230 * 1231 * credentials = "Digest" digest-response 1232 * digest-response = 1#( username | realm | nonce | digest-uri 1233 * | response | [ algorithm ] | [cnonce] | 1234 * [opaque] | [message-qop] | 1235 * [nonce-count] | [auth-param] ) 1236 * username = "username" "=" username-value 1237 * username-value = quoted-string 1238 * digest-uri = "uri" "=" digest-uri-value 1239 * digest-uri-value = request-uri ; As specified by HTTP/1.1 1240 * message-qop = "qop" "=" qop-value 1241 * cnonce = "cnonce" "=" cnonce-value 1242 * cnonce-value = nonce-value 1243 * nonce-count = "nc" "=" nc-value 1244 * nc-value = 8LHEX 1245 * response = "response" "=" request-digest 1246 * request-digest = <"> 32LHEX <"> 1247 */ 1248 static int 1249 http_digest_auth(conn_t *conn, const char *hdr, http_auth_challenge_t *c, 1250 http_auth_params_t *parms, struct url *url) 1251 { 1252 int r; 1253 char noncecount[10]; 1254 char cnonce[40]; 1255 char *options = NULL; 1256 1257 if (!c->realm || !c->nonce) { 1258 DEBUGF("realm/nonce not set in challenge\n"); 1259 return(-1); 1260 } 1261 if (!c->algo) 1262 c->algo = strdup(""); 1263 1264 if (asprintf(&options, "%s%s%s%s", 1265 *c->algo? ",algorithm=" : "", c->algo, 1266 c->opaque? ",opaque=" : "", c->opaque?c->opaque:"") < 0) 1267 return (-1); 1268 1269 if (!c->qop) { 1270 c->qop = strdup(""); 1271 *noncecount = 0; 1272 *cnonce = 0; 1273 } else { 1274 c->nc++; 1275 sprintf(noncecount, "%08x", c->nc); 1276 /* We don't try very hard with the cnonce ... */ 1277 sprintf(cnonce, "%x%lx", getpid(), (unsigned long)time(0)); 1278 } 1279 1280 HASHHEX HA1; 1281 DigestCalcHA1(c->algo, parms->user, c->realm, 1282 parms->password, c->nonce, cnonce, HA1); 1283 DEBUGF("HA1: [%s]\n", HA1); 1284 HASHHEX digest; 1285 DigestCalcResponse(HA1, c->nonce, noncecount, cnonce, c->qop, 1286 "GET", url->doc, "", digest); 1287 1288 if (c->qop[0]) { 1289 r = http_cmd(conn, "%s: Digest username=\"%s\",realm=\"%s\"," 1290 "nonce=\"%s\",uri=\"%s\",response=\"%s\"," 1291 "qop=\"auth\", cnonce=\"%s\", nc=%s%s", 1292 hdr, parms->user, c->realm, 1293 c->nonce, url->doc, digest, 1294 cnonce, noncecount, options); 1295 } else { 1296 r = http_cmd(conn, "%s: Digest username=\"%s\",realm=\"%s\"," 1297 "nonce=\"%s\",uri=\"%s\",response=\"%s\"%s", 1298 hdr, parms->user, c->realm, 1299 c->nonce, url->doc, digest, options); 1300 } 1301 if (options) 1302 free(options); 1303 return (r); 1304 } 1305 1306 /* 1307 * Encode username and password 1308 */ 1309 static int 1310 http_basic_auth(conn_t *conn, const char *hdr, const char *usr, const char *pwd) 1311 { 1312 char *upw, *auth; 1313 int r; 1314 1315 DEBUGF("basic: usr: [%s]\n", usr); 1316 DEBUGF("basic: pwd: [%s]\n", pwd); 1317 if (asprintf(&upw, "%s:%s", usr, pwd) == -1) 1318 return (-1); 1319 auth = http_base64(upw); 1320 free(upw); 1321 if (auth == NULL) 1322 return (-1); 1323 r = http_cmd(conn, "%s: Basic %s", hdr, auth); 1324 free(auth); 1325 return (r); 1326 } 1327 1328 /* 1329 * Chose the challenge to answer and call the appropriate routine to 1330 * produce the header. 1331 */ 1332 static int 1333 http_authorize(conn_t *conn, const char *hdr, http_auth_challenges_t *cs, 1334 http_auth_params_t *parms, struct url *url) 1335 { 1336 http_auth_challenge_t *digest = NULL; 1337 int i; 1338 1339 /* If user or pass are null we're not happy */ 1340 if (!parms->user || !parms->password) { 1341 DEBUGF("NULL usr or pass\n"); 1342 return (-1); 1343 } 1344 1345 /* Look for a Digest */ 1346 for (i = 0; i < cs->count; i++) { 1347 if (cs->challenges[i]->scheme == HTTPAS_DIGEST) 1348 digest = cs->challenges[i]; 1349 } 1350 1351 /* Error if "Digest" was specified and there is no Digest challenge */ 1352 if (!digest && 1353 (parms->scheme && strcasecmp(parms->scheme, "digest") == 0)) { 1354 DEBUGF("Digest auth in env, not supported by peer\n"); 1355 return (-1); 1356 } 1357 /* 1358 * If "basic" was specified in the environment, or there is no Digest 1359 * challenge, do the basic thing. Don't need a challenge for this, 1360 * so no need to check basic!=NULL 1361 */ 1362 if (!digest || 1363 (parms->scheme && strcasecmp(parms->scheme, "basic") == 0)) 1364 return (http_basic_auth(conn,hdr,parms->user,parms->password)); 1365 1366 /* Else, prefer digest. We just checked that it's not NULL */ 1367 return (http_digest_auth(conn, hdr, digest, parms, url)); 1368 } 1369 1370 /***************************************************************************** 1371 * Helper functions for connecting to a server or proxy 1372 */ 1373 1374 /* 1375 * Connect to the correct HTTP server or proxy. 1376 */ 1377 static conn_t * 1378 http_connect(struct url *URL, struct url *purl, const char *flags) 1379 { 1380 struct url *curl; 1381 conn_t *conn; 1382 hdr_t h; 1383 http_headerbuf_t headerbuf; 1384 const char *p; 1385 int verbose; 1386 int af, val; 1387 int serrno; 1388 bool isproxyauth = false; 1389 http_auth_challenges_t proxy_challenges; 1390 1391 #ifdef INET6 1392 af = AF_UNSPEC; 1393 #else 1394 af = AF_INET; 1395 #endif 1396 1397 verbose = CHECK_FLAG('v'); 1398 if (CHECK_FLAG('4')) 1399 af = AF_INET; 1400 #ifdef INET6 1401 else if (CHECK_FLAG('6')) 1402 af = AF_INET6; 1403 #endif 1404 1405 curl = (purl != NULL) ? purl : URL; 1406 1407 retry: 1408 if ((conn = fetch_connect(curl->host, curl->port, af, verbose)) == NULL) 1409 /* fetch_connect() has already set an error code */ 1410 return (NULL); 1411 init_http_headerbuf(&headerbuf); 1412 if (strcmp(URL->scheme, SCHEME_HTTPS) == 0 && purl) { 1413 init_http_auth_challenges(&proxy_challenges); 1414 http_cmd(conn, "CONNECT %s:%d HTTP/1.1", URL->host, URL->port); 1415 http_cmd(conn, "Host: %s:%d", URL->host, URL->port); 1416 if (isproxyauth) { 1417 http_auth_params_t aparams; 1418 init_http_auth_params(&aparams); 1419 if (*purl->user || *purl->pwd) { 1420 aparams.user = strdup(purl->user); 1421 aparams.password = strdup(purl->pwd); 1422 } else if ((p = getenv("HTTP_PROXY_AUTH")) != NULL && 1423 *p != '\0') { 1424 if (http_authfromenv(p, &aparams) < 0) { 1425 http_seterr(HTTP_NEED_PROXY_AUTH); 1426 fetch_syserr(); 1427 goto ouch; 1428 } 1429 } else if (fetch_netrc_auth(purl) == 0) { 1430 aparams.user = strdup(purl->user); 1431 aparams.password = strdup(purl->pwd); 1432 } else { 1433 /* 1434 * No auth information found in system - exiting 1435 * with warning. 1436 */ 1437 warnx("Missing username and/or password set"); 1438 fetch_syserr(); 1439 goto ouch; 1440 } 1441 http_authorize(conn, "Proxy-Authorization", 1442 &proxy_challenges, &aparams, purl); 1443 clean_http_auth_params(&aparams); 1444 } 1445 http_cmd(conn, ""); 1446 /* Get reply from CONNECT Tunnel attempt */ 1447 int httpreply = http_get_reply(conn); 1448 if (httpreply != HTTP_OK) { 1449 http_seterr(httpreply); 1450 /* If the error is a 407/HTTP_NEED_PROXY_AUTH */ 1451 if (httpreply == HTTP_NEED_PROXY_AUTH && 1452 ! isproxyauth) { 1453 /* Try again with authentication. */ 1454 clean_http_headerbuf(&headerbuf); 1455 fetch_close(conn); 1456 isproxyauth = true; 1457 goto retry; 1458 } 1459 goto ouch; 1460 } 1461 /* Read and discard the rest of the proxy response */ 1462 if (fetch_getln(conn) < 0) { 1463 fetch_syserr(); 1464 goto ouch; 1465 } 1466 do { 1467 switch ((h = http_next_header(conn, &headerbuf, &p))) { 1468 case hdr_syserror: 1469 fetch_syserr(); 1470 goto ouch; 1471 case hdr_error: 1472 http_seterr(HTTP_PROTOCOL_ERROR); 1473 goto ouch; 1474 default: 1475 /* ignore */ ; 1476 } 1477 } while (h > hdr_end); 1478 } 1479 if (strcmp(URL->scheme, SCHEME_HTTPS) == 0 && 1480 fetch_ssl(conn, URL, verbose) == -1) { 1481 /* grrr */ 1482 errno = EAUTH; 1483 fetch_syserr(); 1484 goto ouch; 1485 } 1486 1487 val = 1; 1488 setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, sizeof(val)); 1489 1490 clean_http_headerbuf(&headerbuf); 1491 return (conn); 1492 ouch: 1493 serrno = errno; 1494 clean_http_headerbuf(&headerbuf); 1495 fetch_close(conn); 1496 errno = serrno; 1497 return (NULL); 1498 } 1499 1500 static struct url * 1501 http_get_proxy(struct url * url, const char *flags) 1502 { 1503 struct url *purl; 1504 char *p; 1505 1506 if (flags != NULL && strchr(flags, 'd') != NULL) 1507 return (NULL); 1508 if (fetch_no_proxy_match(url->host)) 1509 return (NULL); 1510 if (((p = getenv("HTTP_PROXY")) || (p = getenv("http_proxy"))) && 1511 *p && (purl = fetchParseURL(p))) { 1512 if (!*purl->scheme) 1513 strcpy(purl->scheme, SCHEME_HTTP); 1514 if (!purl->port) 1515 purl->port = fetch_default_proxy_port(purl->scheme); 1516 if (strcmp(purl->scheme, SCHEME_HTTP) == 0) 1517 return (purl); 1518 fetchFreeURL(purl); 1519 } 1520 return (NULL); 1521 } 1522 1523 static void 1524 http_print_html(FILE *out, FILE *in) 1525 { 1526 ssize_t len = 0; 1527 size_t cap; 1528 char *line = NULL, *p, *q; 1529 int comment, tag; 1530 1531 comment = tag = 0; 1532 while ((len = getline(&line, &cap, in)) >= 0) { 1533 while (len && isspace((unsigned char)line[len - 1])) 1534 --len; 1535 for (p = q = line; q < line + len; ++q) { 1536 if (comment && *q == '-') { 1537 if (q + 2 < line + len && 1538 strcmp(q, "-->") == 0) { 1539 tag = comment = 0; 1540 q += 2; 1541 } 1542 } else if (tag && !comment && *q == '>') { 1543 p = q + 1; 1544 tag = 0; 1545 } else if (!tag && *q == '<') { 1546 if (q > p) 1547 fwrite(p, q - p, 1, out); 1548 tag = 1; 1549 if (q + 3 < line + len && 1550 strcmp(q, "<!--") == 0) { 1551 comment = 1; 1552 q += 3; 1553 } 1554 } 1555 } 1556 if (!tag && q > p) 1557 fwrite(p, q - p, 1, out); 1558 fputc('\n', out); 1559 } 1560 1561 free(line); 1562 } 1563 1564 1565 /***************************************************************************** 1566 * Core 1567 */ 1568 1569 FILE * 1570 http_request(struct url *URL, const char *op, struct url_stat *us, 1571 struct url *purl, const char *flags) 1572 { 1573 1574 return (http_request_body(URL, op, us, purl, flags, NULL, NULL)); 1575 } 1576 1577 /* 1578 * Send a request and process the reply 1579 * 1580 * XXX This function is way too long, the do..while loop should be split 1581 * XXX off into a separate function. 1582 */ 1583 FILE * 1584 http_request_body(struct url *URL, const char *op, struct url_stat *us, 1585 struct url *purl, const char *flags, const char *content_type, 1586 const char *body) 1587 { 1588 char timebuf[80]; 1589 char hbuf[MAXHOSTNAMELEN + 7], *host; 1590 conn_t *conn; 1591 struct url *url, *new; 1592 int chunked, direct, ims, noredirect, verbose; 1593 int e, i, n, val; 1594 off_t offset, clength, length, size; 1595 time_t mtime; 1596 const char *p; 1597 FILE *f; 1598 hdr_t h; 1599 struct tm *timestruct; 1600 http_headerbuf_t headerbuf; 1601 http_auth_challenges_t server_challenges; 1602 http_auth_challenges_t proxy_challenges; 1603 size_t body_len; 1604 1605 /* The following calls don't allocate anything */ 1606 init_http_headerbuf(&headerbuf); 1607 init_http_auth_challenges(&server_challenges); 1608 init_http_auth_challenges(&proxy_challenges); 1609 1610 direct = CHECK_FLAG('d'); 1611 noredirect = CHECK_FLAG('A'); 1612 verbose = CHECK_FLAG('v'); 1613 ims = CHECK_FLAG('i'); 1614 1615 if (direct && purl) { 1616 fetchFreeURL(purl); 1617 purl = NULL; 1618 } 1619 1620 /* try the provided URL first */ 1621 url = URL; 1622 1623 n = MAX_REDIRECT; 1624 i = 0; 1625 1626 e = HTTP_PROTOCOL_ERROR; 1627 do { 1628 new = NULL; 1629 chunked = 0; 1630 offset = 0; 1631 clength = -1; 1632 length = -1; 1633 size = -1; 1634 mtime = 0; 1635 1636 /* check port */ 1637 if (!url->port) 1638 url->port = fetch_default_port(url->scheme); 1639 1640 /* were we redirected to an FTP URL? */ 1641 if (purl == NULL && strcmp(url->scheme, SCHEME_FTP) == 0) { 1642 if (strcmp(op, "GET") == 0) 1643 return (ftp_request(url, "RETR", us, purl, flags)); 1644 else if (strcmp(op, "HEAD") == 0) 1645 return (ftp_request(url, "STAT", us, purl, flags)); 1646 } 1647 1648 /* connect to server or proxy */ 1649 if ((conn = http_connect(url, purl, flags)) == NULL) 1650 goto ouch; 1651 1652 /* append port number only if necessary */ 1653 host = url->host; 1654 if (url->port != fetch_default_port(url->scheme)) { 1655 snprintf(hbuf, sizeof(hbuf), "%s:%d", host, url->port); 1656 host = hbuf; 1657 } 1658 1659 /* send request */ 1660 if (verbose) 1661 fetch_info("requesting %s://%s%s", 1662 url->scheme, host, url->doc); 1663 if (purl && strcmp(url->scheme, SCHEME_HTTPS) != 0) { 1664 http_cmd(conn, "%s %s://%s%s HTTP/1.1", 1665 op, url->scheme, host, url->doc); 1666 } else { 1667 http_cmd(conn, "%s %s HTTP/1.1", 1668 op, url->doc); 1669 } 1670 1671 if (ims && url->ims_time) { 1672 timestruct = gmtime((time_t *)&url->ims_time); 1673 (void)strftime(timebuf, 80, "%a, %d %b %Y %T GMT", 1674 timestruct); 1675 if (verbose) 1676 fetch_info("If-Modified-Since: %s", timebuf); 1677 http_cmd(conn, "If-Modified-Since: %s", timebuf); 1678 } 1679 /* virtual host */ 1680 http_cmd(conn, "Host: %s", host); 1681 1682 /* 1683 * Proxy authorization: we only send auth after we received 1684 * a 407 error. We do not first try basic anyway (changed 1685 * when support was added for digest-auth) 1686 */ 1687 if (purl && proxy_challenges.valid) { 1688 http_auth_params_t aparams; 1689 init_http_auth_params(&aparams); 1690 if (*purl->user || *purl->pwd) { 1691 aparams.user = strdup(purl->user); 1692 aparams.password = strdup(purl->pwd); 1693 } else if ((p = getenv("HTTP_PROXY_AUTH")) != NULL && 1694 *p != '\0') { 1695 if (http_authfromenv(p, &aparams) < 0) { 1696 http_seterr(HTTP_NEED_PROXY_AUTH); 1697 goto ouch; 1698 } 1699 } else if (fetch_netrc_auth(purl) == 0) { 1700 aparams.user = strdup(purl->user); 1701 aparams.password = strdup(purl->pwd); 1702 } 1703 http_authorize(conn, "Proxy-Authorization", 1704 &proxy_challenges, &aparams, url); 1705 clean_http_auth_params(&aparams); 1706 } 1707 1708 /* 1709 * Server authorization: we never send "a priori" 1710 * Basic auth, which used to be done if user/pass were 1711 * set in the url. This would be weird because we'd send the 1712 * password in the clear even if Digest is finally to be 1713 * used (it would have made more sense for the 1714 * pre-digest version to do this when Basic was specified 1715 * in the environment) 1716 */ 1717 if (server_challenges.valid) { 1718 http_auth_params_t aparams; 1719 init_http_auth_params(&aparams); 1720 if (*url->user || *url->pwd) { 1721 aparams.user = strdup(url->user); 1722 aparams.password = strdup(url->pwd); 1723 } else if ((p = getenv("HTTP_AUTH")) != NULL && 1724 *p != '\0') { 1725 if (http_authfromenv(p, &aparams) < 0) { 1726 http_seterr(HTTP_NEED_AUTH); 1727 goto ouch; 1728 } 1729 } else if (fetch_netrc_auth(url) == 0) { 1730 aparams.user = strdup(url->user); 1731 aparams.password = strdup(url->pwd); 1732 } else if (fetchAuthMethod && 1733 fetchAuthMethod(url) == 0) { 1734 aparams.user = strdup(url->user); 1735 aparams.password = strdup(url->pwd); 1736 } else { 1737 http_seterr(HTTP_NEED_AUTH); 1738 goto ouch; 1739 } 1740 http_authorize(conn, "Authorization", 1741 &server_challenges, &aparams, url); 1742 clean_http_auth_params(&aparams); 1743 } 1744 1745 /* other headers */ 1746 if ((p = getenv("HTTP_ACCEPT")) != NULL) { 1747 if (*p != '\0') 1748 http_cmd(conn, "Accept: %s", p); 1749 } else { 1750 http_cmd(conn, "Accept: */*"); 1751 } 1752 if ((p = getenv("HTTP_REFERER")) != NULL && *p != '\0') { 1753 if (strcasecmp(p, "auto") == 0) 1754 http_cmd(conn, "Referer: %s://%s%s", 1755 url->scheme, host, url->doc); 1756 else 1757 http_cmd(conn, "Referer: %s", p); 1758 } 1759 if ((p = getenv("HTTP_USER_AGENT")) != NULL) { 1760 /* no User-Agent if defined but empty */ 1761 if (*p != '\0') 1762 http_cmd(conn, "User-Agent: %s", p); 1763 } else { 1764 /* default User-Agent */ 1765 http_cmd(conn, "User-Agent: %s " _LIBFETCH_VER, 1766 getprogname()); 1767 } 1768 if (url->offset > 0) 1769 http_cmd(conn, "Range: bytes=%lld-", (long long)url->offset); 1770 http_cmd(conn, "Connection: close"); 1771 1772 if (body) { 1773 body_len = strlen(body); 1774 http_cmd(conn, "Content-Length: %zu", body_len); 1775 if (content_type != NULL) 1776 http_cmd(conn, "Content-Type: %s", content_type); 1777 } 1778 1779 http_cmd(conn, ""); 1780 1781 if (body) 1782 fetch_write(conn, body, body_len); 1783 1784 /* 1785 * Force the queued request to be dispatched. Normally, one 1786 * would do this with shutdown(2) but squid proxies can be 1787 * configured to disallow such half-closed connections. To 1788 * be compatible with such configurations, fiddle with socket 1789 * options to force the pending data to be written. 1790 */ 1791 val = 0; 1792 setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, 1793 sizeof(val)); 1794 val = 1; 1795 setsockopt(conn->sd, IPPROTO_TCP, TCP_NODELAY, &val, 1796 sizeof(val)); 1797 1798 /* get reply */ 1799 switch (http_get_reply(conn)) { 1800 case HTTP_OK: 1801 case HTTP_PARTIAL: 1802 case HTTP_NOT_MODIFIED: 1803 /* fine */ 1804 break; 1805 case HTTP_MOVED_PERM: 1806 case HTTP_MOVED_TEMP: 1807 case HTTP_TEMP_REDIRECT: 1808 case HTTP_PERM_REDIRECT: 1809 case HTTP_SEE_OTHER: 1810 case HTTP_USE_PROXY: 1811 /* 1812 * Not so fine, but we still have to read the 1813 * headers to get the new location. 1814 */ 1815 break; 1816 case HTTP_NEED_AUTH: 1817 if (server_challenges.valid) { 1818 /* 1819 * We already sent out authorization code, 1820 * so there's nothing more we can do. 1821 */ 1822 http_seterr(conn->err); 1823 goto ouch; 1824 } 1825 /* try again, but send the password this time */ 1826 if (verbose) 1827 fetch_info("server requires authorization"); 1828 break; 1829 case HTTP_NEED_PROXY_AUTH: 1830 if (proxy_challenges.valid) { 1831 /* 1832 * We already sent our proxy 1833 * authorization code, so there's 1834 * nothing more we can do. */ 1835 http_seterr(conn->err); 1836 goto ouch; 1837 } 1838 /* try again, but send the password this time */ 1839 if (verbose) 1840 fetch_info("proxy requires authorization"); 1841 break; 1842 case HTTP_BAD_RANGE: 1843 /* 1844 * This can happen if we ask for 0 bytes because 1845 * we already have the whole file. Consider this 1846 * a success for now, and check sizes later. 1847 */ 1848 break; 1849 case HTTP_PROTOCOL_ERROR: 1850 /* fall through */ 1851 case -1: 1852 fetch_syserr(); 1853 goto ouch; 1854 default: 1855 http_seterr(conn->err); 1856 if (!verbose) 1857 goto ouch; 1858 /* fall through so we can get the full error message */ 1859 } 1860 1861 /* get headers. http_next_header expects one line readahead */ 1862 if (fetch_getln(conn) == -1) { 1863 fetch_syserr(); 1864 goto ouch; 1865 } 1866 do { 1867 switch ((h = http_next_header(conn, &headerbuf, &p))) { 1868 case hdr_syserror: 1869 fetch_syserr(); 1870 goto ouch; 1871 case hdr_error: 1872 http_seterr(HTTP_PROTOCOL_ERROR); 1873 goto ouch; 1874 case hdr_content_length: 1875 http_parse_length(p, &clength); 1876 break; 1877 case hdr_content_range: 1878 http_parse_range(p, &offset, &length, &size); 1879 break; 1880 case hdr_last_modified: 1881 http_parse_mtime(p, &mtime); 1882 break; 1883 case hdr_location: 1884 if (!HTTP_REDIRECT(conn->err)) 1885 break; 1886 /* 1887 * if the A flag is set, we don't follow 1888 * temporary redirects. 1889 */ 1890 if (noredirect && 1891 conn->err != HTTP_MOVED_PERM && 1892 conn->err != HTTP_PERM_REDIRECT && 1893 conn->err != HTTP_USE_PROXY) { 1894 n = 1; 1895 break; 1896 } 1897 if (new) 1898 free(new); 1899 if (verbose) 1900 fetch_info("%d redirect to %s", 1901 conn->err, p); 1902 if (*p == '/') 1903 /* absolute path */ 1904 new = fetchMakeURL(url->scheme, url->host, 1905 url->port, p, url->user, url->pwd); 1906 else 1907 new = fetchParseURL(p); 1908 if (new == NULL) { 1909 /* XXX should set an error code */ 1910 DEBUGF("failed to parse new URL\n"); 1911 goto ouch; 1912 } 1913 1914 /* Only copy credentials if the host matches */ 1915 if (strcmp(new->host, url->host) == 0 && 1916 !*new->user && !*new->pwd) { 1917 strcpy(new->user, url->user); 1918 strcpy(new->pwd, url->pwd); 1919 } 1920 new->offset = url->offset; 1921 new->length = url->length; 1922 new->ims_time = url->ims_time; 1923 break; 1924 case hdr_transfer_encoding: 1925 /* XXX weak test*/ 1926 chunked = (strcasecmp(p, "chunked") == 0); 1927 break; 1928 case hdr_www_authenticate: 1929 if (conn->err != HTTP_NEED_AUTH) 1930 break; 1931 if (http_parse_authenticate(p, &server_challenges) == 0) 1932 ++n; 1933 break; 1934 case hdr_proxy_authenticate: 1935 if (conn->err != HTTP_NEED_PROXY_AUTH) 1936 break; 1937 if (http_parse_authenticate(p, &proxy_challenges) == 0) 1938 ++n; 1939 break; 1940 case hdr_end: 1941 /* fall through */ 1942 case hdr_unknown: 1943 /* ignore */ 1944 break; 1945 } 1946 } while (h > hdr_end); 1947 1948 /* we need to provide authentication */ 1949 if (conn->err == HTTP_NEED_AUTH || 1950 conn->err == HTTP_NEED_PROXY_AUTH) { 1951 e = conn->err; 1952 if ((conn->err == HTTP_NEED_AUTH && 1953 !server_challenges.valid) || 1954 (conn->err == HTTP_NEED_PROXY_AUTH && 1955 !proxy_challenges.valid)) { 1956 /* 401/7 but no www/proxy-authenticate ?? */ 1957 DEBUGF("%03d without auth header\n", conn->err); 1958 goto ouch; 1959 } 1960 fetch_close(conn); 1961 conn = NULL; 1962 continue; 1963 } 1964 1965 /* requested range not satisfiable */ 1966 if (conn->err == HTTP_BAD_RANGE) { 1967 if (url->offset > 0 && url->length == 0) { 1968 /* asked for 0 bytes; fake it */ 1969 offset = url->offset; 1970 clength = -1; 1971 conn->err = HTTP_OK; 1972 break; 1973 } else { 1974 http_seterr(conn->err); 1975 goto ouch; 1976 } 1977 } 1978 1979 /* we have a hit or an error */ 1980 if (conn->err == HTTP_OK 1981 || conn->err == HTTP_NOT_MODIFIED 1982 || conn->err == HTTP_PARTIAL 1983 || HTTP_ERROR(conn->err)) 1984 break; 1985 1986 /* all other cases: we got a redirect */ 1987 e = conn->err; 1988 clean_http_auth_challenges(&server_challenges); 1989 fetch_close(conn); 1990 conn = NULL; 1991 if (!new) { 1992 DEBUGF("redirect with no new location\n"); 1993 break; 1994 } 1995 if (url != URL) 1996 fetchFreeURL(url); 1997 url = new; 1998 } while (++i < n); 1999 2000 /* we failed, or ran out of retries */ 2001 if (conn == NULL) { 2002 http_seterr(e); 2003 goto ouch; 2004 } 2005 2006 DEBUGF("offset %lld, length %lld, size %lld, clength %lld\n", 2007 (long long)offset, (long long)length, 2008 (long long)size, (long long)clength); 2009 2010 if (conn->err == HTTP_NOT_MODIFIED) { 2011 http_seterr(HTTP_NOT_MODIFIED); 2012 return (NULL); 2013 } 2014 2015 /* check for inconsistencies */ 2016 if (clength != -1 && length != -1 && clength != length) { 2017 http_seterr(HTTP_PROTOCOL_ERROR); 2018 goto ouch; 2019 } 2020 if (clength == -1) 2021 clength = length; 2022 if (clength != -1) 2023 length = offset + clength; 2024 if (length != -1 && size != -1 && length != size) { 2025 http_seterr(HTTP_PROTOCOL_ERROR); 2026 goto ouch; 2027 } 2028 if (size == -1) 2029 size = length; 2030 2031 /* fill in stats */ 2032 if (us) { 2033 us->size = size; 2034 us->atime = us->mtime = mtime; 2035 } 2036 2037 /* too far? */ 2038 if (URL->offset > 0 && offset > URL->offset) { 2039 http_seterr(HTTP_PROTOCOL_ERROR); 2040 goto ouch; 2041 } 2042 2043 /* report back real offset and size */ 2044 URL->offset = offset; 2045 URL->length = clength; 2046 2047 /* wrap it up in a FILE */ 2048 if ((f = http_funopen(conn, chunked)) == NULL) { 2049 fetch_syserr(); 2050 goto ouch; 2051 } 2052 2053 if (url != URL) 2054 fetchFreeURL(url); 2055 if (purl) 2056 fetchFreeURL(purl); 2057 2058 if (HTTP_ERROR(conn->err)) { 2059 http_print_html(stderr, f); 2060 fclose(f); 2061 f = NULL; 2062 } 2063 clean_http_headerbuf(&headerbuf); 2064 clean_http_auth_challenges(&server_challenges); 2065 clean_http_auth_challenges(&proxy_challenges); 2066 return (f); 2067 2068 ouch: 2069 if (url != URL) 2070 fetchFreeURL(url); 2071 if (purl) 2072 fetchFreeURL(purl); 2073 if (conn != NULL) 2074 fetch_close(conn); 2075 clean_http_headerbuf(&headerbuf); 2076 clean_http_auth_challenges(&server_challenges); 2077 clean_http_auth_challenges(&proxy_challenges); 2078 return (NULL); 2079 } 2080 2081 2082 /***************************************************************************** 2083 * Entry points 2084 */ 2085 2086 /* 2087 * Retrieve and stat a file by HTTP 2088 */ 2089 FILE * 2090 fetchXGetHTTP(struct url *URL, struct url_stat *us, const char *flags) 2091 { 2092 return (http_request(URL, "GET", us, http_get_proxy(URL, flags), flags)); 2093 } 2094 2095 /* 2096 * Retrieve a file by HTTP 2097 */ 2098 FILE * 2099 fetchGetHTTP(struct url *URL, const char *flags) 2100 { 2101 return (fetchXGetHTTP(URL, NULL, flags)); 2102 } 2103 2104 /* 2105 * Store a file by HTTP 2106 */ 2107 FILE * 2108 fetchPutHTTP(struct url *URL __unused, const char *flags __unused) 2109 { 2110 warnx("fetchPutHTTP(): not implemented"); 2111 return (NULL); 2112 } 2113 2114 /* 2115 * Get an HTTP document's metadata 2116 */ 2117 int 2118 fetchStatHTTP(struct url *URL, struct url_stat *us, const char *flags) 2119 { 2120 FILE *f; 2121 2122 f = http_request(URL, "HEAD", us, http_get_proxy(URL, flags), flags); 2123 if (f == NULL) 2124 return (-1); 2125 fclose(f); 2126 return (0); 2127 } 2128 2129 /* 2130 * List a directory 2131 */ 2132 struct url_ent * 2133 fetchListHTTP(struct url *url __unused, const char *flags __unused) 2134 { 2135 warnx("fetchListHTTP(): not implemented"); 2136 return (NULL); 2137 } 2138 2139 /* 2140 * Arbitrary HTTP verb and content requests 2141 */ 2142 FILE * 2143 fetchReqHTTP(struct url *URL, const char *method, const char *flags, 2144 const char *content_type, const char *body) 2145 { 2146 2147 return (http_request_body(URL, method, NULL, http_get_proxy(URL, flags), 2148 flags, content_type, body)); 2149 } 2150