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 * $FreeBSD: head/lib/libfetch/http.c 351573 2019-08-28 17:01:28Z markj $ 31 */ 32 33 #include <sys/cdefs.h> 34 35 /* 36 * The following copyright applies to the base64 code: 37 * 38 *- 39 * Copyright 1997 Massachusetts Institute of Technology 40 * 41 * Permission to use, copy, modify, and distribute this software and 42 * its documentation for any purpose and without fee is hereby 43 * granted, provided that both the above copyright notice and this 44 * permission notice appear in all copies, that both the above 45 * copyright notice and this permission notice appear in all 46 * supporting documentation, and that the name of M.I.T. not be used 47 * in advertising or publicity pertaining to distribution of the 48 * software without specific, written prior permission. M.I.T. makes 49 * no representations about the suitability of this software for any 50 * purpose. It is provided "as is" without express or implied 51 * warranty. 52 * 53 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS 54 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE, 55 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 56 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT 57 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 58 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 59 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 60 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 61 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 62 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 63 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 64 * SUCH DAMAGE. 65 */ 66 67 #include <sys/param.h> 68 #include <sys/socket.h> 69 #include <sys/time.h> 70 71 #include <ctype.h> 72 #include <err.h> 73 #include <errno.h> 74 #include <locale.h> 75 #include <netdb.h> 76 #include <stdarg.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, r; 980 981 l = strlen(src); 982 if ((str = malloc(((l + 2) / 3) * 4 + 1)) == NULL) 983 return (NULL); 984 dst = str; 985 r = 0; 986 987 while (l >= 3) { 988 t = (src[0] << 16) | (src[1] << 8) | src[2]; 989 dst[0] = base64[(t >> 18) & 0x3f]; 990 dst[1] = base64[(t >> 12) & 0x3f]; 991 dst[2] = base64[(t >> 6) & 0x3f]; 992 dst[3] = base64[(t >> 0) & 0x3f]; 993 src += 3; l -= 3; 994 dst += 4; r += 4; 995 } 996 997 switch (l) { 998 case 2: 999 t = (src[0] << 16) | (src[1] << 8); 1000 dst[0] = base64[(t >> 18) & 0x3f]; 1001 dst[1] = base64[(t >> 12) & 0x3f]; 1002 dst[2] = base64[(t >> 6) & 0x3f]; 1003 dst[3] = '='; 1004 dst += 4; 1005 r += 4; 1006 break; 1007 case 1: 1008 t = src[0] << 16; 1009 dst[0] = base64[(t >> 18) & 0x3f]; 1010 dst[1] = base64[(t >> 12) & 0x3f]; 1011 dst[2] = dst[3] = '='; 1012 dst += 4; 1013 r += 4; 1014 break; 1015 case 0: 1016 break; 1017 } 1018 1019 *dst = 0; 1020 return (str); 1021 } 1022 1023 1024 /* 1025 * Extract authorization parameters from environment value. 1026 * The value is like scheme:realm:user:pass 1027 */ 1028 typedef struct { 1029 char *scheme; 1030 char *realm; 1031 char *user; 1032 char *password; 1033 } http_auth_params_t; 1034 1035 static void 1036 init_http_auth_params(http_auth_params_t *s) 1037 { 1038 s->scheme = s->realm = s->user = s->password = NULL; 1039 } 1040 1041 static void 1042 clean_http_auth_params(http_auth_params_t *s) 1043 { 1044 if (s->scheme) 1045 free(s->scheme); 1046 if (s->realm) 1047 free(s->realm); 1048 if (s->user) 1049 free(s->user); 1050 if (s->password) 1051 free(s->password); 1052 init_http_auth_params(s); 1053 } 1054 1055 static int 1056 http_authfromenv(const char *p, http_auth_params_t *parms) 1057 { 1058 int ret = -1; 1059 char *v, *ve; 1060 char *str = strdup(p); 1061 1062 if (str == NULL) { 1063 fetch_syserr(); 1064 return (-1); 1065 } 1066 v = str; 1067 1068 if ((ve = strchr(v, ':')) == NULL) 1069 goto out; 1070 1071 *ve = 0; 1072 if ((parms->scheme = strdup(v)) == NULL) { 1073 fetch_syserr(); 1074 goto out; 1075 } 1076 v = ve + 1; 1077 1078 if ((ve = strchr(v, ':')) == NULL) 1079 goto out; 1080 1081 *ve = 0; 1082 if ((parms->realm = strdup(v)) == NULL) { 1083 fetch_syserr(); 1084 goto out; 1085 } 1086 v = ve + 1; 1087 1088 if ((ve = strchr(v, ':')) == NULL) 1089 goto out; 1090 1091 *ve = 0; 1092 if ((parms->user = strdup(v)) == NULL) { 1093 fetch_syserr(); 1094 goto out; 1095 } 1096 v = ve + 1; 1097 1098 1099 if ((parms->password = strdup(v)) == NULL) { 1100 fetch_syserr(); 1101 goto out; 1102 } 1103 ret = 0; 1104 out: 1105 if (ret == -1) 1106 clean_http_auth_params(parms); 1107 if (str) 1108 free(str); 1109 return (ret); 1110 } 1111 1112 1113 /* 1114 * Digest response: the code to compute the digest is taken from the 1115 * sample implementation in RFC2616 1116 */ 1117 #define IN const 1118 #define OUT 1119 1120 #define HASHLEN 16 1121 typedef char HASH[HASHLEN]; 1122 #define HASHHEXLEN 32 1123 typedef char HASHHEX[HASHHEXLEN+1]; 1124 1125 static const char *hexchars = "0123456789abcdef"; 1126 static void 1127 CvtHex(IN HASH Bin, OUT HASHHEX Hex) 1128 { 1129 unsigned short i; 1130 unsigned char j; 1131 1132 for (i = 0; i < HASHLEN; i++) { 1133 j = (Bin[i] >> 4) & 0xf; 1134 Hex[i*2] = hexchars[j]; 1135 j = Bin[i] & 0xf; 1136 Hex[i*2+1] = hexchars[j]; 1137 } 1138 Hex[HASHHEXLEN] = '\0'; 1139 }; 1140 1141 /* calculate H(A1) as per spec */ 1142 static void 1143 DigestCalcHA1( 1144 IN char * pszAlg, 1145 IN char * pszUserName, 1146 IN char * pszRealm, 1147 IN char * pszPassword, 1148 IN char * pszNonce, 1149 IN char * pszCNonce, 1150 OUT HASHHEX SessionKey 1151 ) 1152 { 1153 MD5_CTX Md5Ctx; 1154 HASH HA1; 1155 1156 MD5Init(&Md5Ctx); 1157 MD5Update(&Md5Ctx, pszUserName, strlen(pszUserName)); 1158 MD5Update(&Md5Ctx, ":", 1); 1159 MD5Update(&Md5Ctx, pszRealm, strlen(pszRealm)); 1160 MD5Update(&Md5Ctx, ":", 1); 1161 MD5Update(&Md5Ctx, pszPassword, strlen(pszPassword)); 1162 MD5Final(HA1, &Md5Ctx); 1163 if (strcasecmp(pszAlg, "md5-sess") == 0) { 1164 1165 MD5Init(&Md5Ctx); 1166 MD5Update(&Md5Ctx, HA1, HASHLEN); 1167 MD5Update(&Md5Ctx, ":", 1); 1168 MD5Update(&Md5Ctx, pszNonce, strlen(pszNonce)); 1169 MD5Update(&Md5Ctx, ":", 1); 1170 MD5Update(&Md5Ctx, pszCNonce, strlen(pszCNonce)); 1171 MD5Final(HA1, &Md5Ctx); 1172 } 1173 CvtHex(HA1, SessionKey); 1174 } 1175 1176 /* calculate request-digest/response-digest as per HTTP Digest spec */ 1177 static void 1178 DigestCalcResponse( 1179 IN HASHHEX HA1, /* H(A1) */ 1180 IN char * pszNonce, /* nonce from server */ 1181 IN char * pszNonceCount, /* 8 hex digits */ 1182 IN char * pszCNonce, /* client nonce */ 1183 IN char * pszQop, /* qop-value: "", "auth", "auth-int" */ 1184 IN char * pszMethod, /* method from the request */ 1185 IN char * pszDigestUri, /* requested URL */ 1186 IN HASHHEX HEntity, /* H(entity body) if qop="auth-int" */ 1187 OUT HASHHEX Response /* request-digest or response-digest */ 1188 ) 1189 { 1190 #if 0 1191 DEBUGF("Calc: HA1[%s] Nonce[%s] qop[%s] method[%s] URI[%s]\n", 1192 HA1, pszNonce, pszQop, pszMethod, pszDigestUri); 1193 #endif 1194 MD5_CTX Md5Ctx; 1195 HASH HA2; 1196 HASH RespHash; 1197 HASHHEX HA2Hex; 1198 1199 // calculate H(A2) 1200 MD5Init(&Md5Ctx); 1201 MD5Update(&Md5Ctx, pszMethod, strlen(pszMethod)); 1202 MD5Update(&Md5Ctx, ":", 1); 1203 MD5Update(&Md5Ctx, pszDigestUri, strlen(pszDigestUri)); 1204 if (strcasecmp(pszQop, "auth-int") == 0) { 1205 MD5Update(&Md5Ctx, ":", 1); 1206 MD5Update(&Md5Ctx, HEntity, HASHHEXLEN); 1207 } 1208 MD5Final(HA2, &Md5Ctx); 1209 CvtHex(HA2, HA2Hex); 1210 1211 // calculate response 1212 MD5Init(&Md5Ctx); 1213 MD5Update(&Md5Ctx, HA1, HASHHEXLEN); 1214 MD5Update(&Md5Ctx, ":", 1); 1215 MD5Update(&Md5Ctx, pszNonce, strlen(pszNonce)); 1216 MD5Update(&Md5Ctx, ":", 1); 1217 if (*pszQop) { 1218 MD5Update(&Md5Ctx, pszNonceCount, strlen(pszNonceCount)); 1219 MD5Update(&Md5Ctx, ":", 1); 1220 MD5Update(&Md5Ctx, pszCNonce, strlen(pszCNonce)); 1221 MD5Update(&Md5Ctx, ":", 1); 1222 MD5Update(&Md5Ctx, pszQop, strlen(pszQop)); 1223 MD5Update(&Md5Ctx, ":", 1); 1224 } 1225 MD5Update(&Md5Ctx, HA2Hex, HASHHEXLEN); 1226 MD5Final(RespHash, &Md5Ctx); 1227 CvtHex(RespHash, Response); 1228 } 1229 1230 /* 1231 * Generate/Send a Digest authorization header 1232 * This looks like: [Proxy-]Authorization: credentials 1233 * 1234 * credentials = "Digest" digest-response 1235 * digest-response = 1#( username | realm | nonce | digest-uri 1236 * | response | [ algorithm ] | [cnonce] | 1237 * [opaque] | [message-qop] | 1238 * [nonce-count] | [auth-param] ) 1239 * username = "username" "=" username-value 1240 * username-value = quoted-string 1241 * digest-uri = "uri" "=" digest-uri-value 1242 * digest-uri-value = request-uri ; As specified by HTTP/1.1 1243 * message-qop = "qop" "=" qop-value 1244 * cnonce = "cnonce" "=" cnonce-value 1245 * cnonce-value = nonce-value 1246 * nonce-count = "nc" "=" nc-value 1247 * nc-value = 8LHEX 1248 * response = "response" "=" request-digest 1249 * request-digest = <"> 32LHEX <"> 1250 */ 1251 static int 1252 http_digest_auth(conn_t *conn, const char *hdr, http_auth_challenge_t *c, 1253 http_auth_params_t *parms, struct url *url) 1254 { 1255 int r; 1256 char noncecount[10]; 1257 char cnonce[40]; 1258 char *options = NULL; 1259 1260 if (!c->realm || !c->nonce) { 1261 DEBUGF("realm/nonce not set in challenge\n"); 1262 return(-1); 1263 } 1264 if (!c->algo) 1265 c->algo = strdup(""); 1266 1267 if (asprintf(&options, "%s%s%s%s", 1268 *c->algo? ",algorithm=" : "", c->algo, 1269 c->opaque? ",opaque=" : "", c->opaque?c->opaque:"") < 0) 1270 return (-1); 1271 1272 if (!c->qop) { 1273 c->qop = strdup(""); 1274 *noncecount = 0; 1275 *cnonce = 0; 1276 } else { 1277 c->nc++; 1278 sprintf(noncecount, "%08x", c->nc); 1279 /* We don't try very hard with the cnonce ... */ 1280 sprintf(cnonce, "%x%lx", getpid(), (unsigned long)time(0)); 1281 } 1282 1283 HASHHEX HA1; 1284 DigestCalcHA1(c->algo, parms->user, c->realm, 1285 parms->password, c->nonce, cnonce, HA1); 1286 DEBUGF("HA1: [%s]\n", HA1); 1287 HASHHEX digest; 1288 DigestCalcResponse(HA1, c->nonce, noncecount, cnonce, c->qop, 1289 "GET", url->doc, "", digest); 1290 1291 if (c->qop[0]) { 1292 r = http_cmd(conn, "%s: Digest username=\"%s\",realm=\"%s\"," 1293 "nonce=\"%s\",uri=\"%s\",response=\"%s\"," 1294 "qop=\"auth\", cnonce=\"%s\", nc=%s%s", 1295 hdr, parms->user, c->realm, 1296 c->nonce, url->doc, digest, 1297 cnonce, noncecount, options); 1298 } else { 1299 r = http_cmd(conn, "%s: Digest username=\"%s\",realm=\"%s\"," 1300 "nonce=\"%s\",uri=\"%s\",response=\"%s\"%s", 1301 hdr, parms->user, c->realm, 1302 c->nonce, url->doc, digest, options); 1303 } 1304 if (options) 1305 free(options); 1306 return (r); 1307 } 1308 1309 /* 1310 * Encode username and password 1311 */ 1312 static int 1313 http_basic_auth(conn_t *conn, const char *hdr, const char *usr, const char *pwd) 1314 { 1315 char *upw, *auth; 1316 int r; 1317 1318 DEBUGF("basic: usr: [%s]\n", usr); 1319 DEBUGF("basic: pwd: [%s]\n", pwd); 1320 if (asprintf(&upw, "%s:%s", usr, pwd) == -1) 1321 return (-1); 1322 auth = http_base64(upw); 1323 free(upw); 1324 if (auth == NULL) 1325 return (-1); 1326 r = http_cmd(conn, "%s: Basic %s", hdr, auth); 1327 free(auth); 1328 return (r); 1329 } 1330 1331 /* 1332 * Chose the challenge to answer and call the appropriate routine to 1333 * produce the header. 1334 */ 1335 static int 1336 http_authorize(conn_t *conn, const char *hdr, http_auth_challenges_t *cs, 1337 http_auth_params_t *parms, struct url *url) 1338 { 1339 http_auth_challenge_t *digest = NULL; 1340 int i; 1341 1342 /* If user or pass are null we're not happy */ 1343 if (!parms->user || !parms->password) { 1344 DEBUGF("NULL usr or pass\n"); 1345 return (-1); 1346 } 1347 1348 /* Look for a Digest */ 1349 for (i = 0; i < cs->count; i++) { 1350 if (cs->challenges[i]->scheme == HTTPAS_DIGEST) 1351 digest = cs->challenges[i]; 1352 } 1353 1354 /* Error if "Digest" was specified and there is no Digest challenge */ 1355 if (!digest && 1356 (parms->scheme && strcasecmp(parms->scheme, "digest") == 0)) { 1357 DEBUGF("Digest auth in env, not supported by peer\n"); 1358 return (-1); 1359 } 1360 /* 1361 * If "basic" was specified in the environment, or there is no Digest 1362 * challenge, do the basic thing. Don't need a challenge for this, 1363 * so no need to check basic!=NULL 1364 */ 1365 if (!digest || 1366 (parms->scheme && strcasecmp(parms->scheme, "basic") == 0)) 1367 return (http_basic_auth(conn,hdr,parms->user,parms->password)); 1368 1369 /* Else, prefer digest. We just checked that it's not NULL */ 1370 return (http_digest_auth(conn, hdr, digest, parms, url)); 1371 } 1372 1373 /***************************************************************************** 1374 * Helper functions for connecting to a server or proxy 1375 */ 1376 1377 /* 1378 * Connect to the correct HTTP server or proxy. 1379 */ 1380 static conn_t * 1381 http_connect(struct url *URL, struct url *purl, const char *flags) 1382 { 1383 struct url *curl; 1384 conn_t *conn; 1385 hdr_t h; 1386 http_headerbuf_t headerbuf; 1387 const char *p; 1388 int verbose; 1389 int af, val; 1390 int serrno; 1391 1392 #ifdef INET6 1393 af = AF_UNSPEC; 1394 #else 1395 af = AF_INET; 1396 #endif 1397 1398 verbose = CHECK_FLAG('v'); 1399 if (CHECK_FLAG('4')) 1400 af = AF_INET; 1401 #ifdef INET6 1402 else if (CHECK_FLAG('6')) 1403 af = AF_INET6; 1404 #endif 1405 1406 curl = (purl != NULL) ? purl : URL; 1407 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 http_cmd(conn, "CONNECT %s:%d HTTP/1.1", 1414 URL->host, URL->port); 1415 http_cmd(conn, "Host: %s:%d", 1416 URL->host, URL->port); 1417 http_cmd(conn, ""); 1418 if (http_get_reply(conn) != HTTP_OK) { 1419 http_seterr(conn->err); 1420 goto ouch; 1421 } 1422 /* Read and discard the rest of the proxy response */ 1423 if (fetch_getln(conn) < 0) { 1424 fetch_syserr(); 1425 goto ouch; 1426 } 1427 do { 1428 switch ((h = http_next_header(conn, &headerbuf, &p))) { 1429 case hdr_syserror: 1430 fetch_syserr(); 1431 goto ouch; 1432 case hdr_error: 1433 http_seterr(HTTP_PROTOCOL_ERROR); 1434 goto ouch; 1435 default: 1436 /* ignore */ ; 1437 } 1438 } while (h > hdr_end); 1439 } 1440 if (strcmp(URL->scheme, SCHEME_HTTPS) == 0 && 1441 fetch_ssl(conn, URL, verbose) == -1) { 1442 /* grrr */ 1443 errno = EAUTH; 1444 fetch_syserr(); 1445 goto ouch; 1446 } 1447 1448 val = 1; 1449 setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, sizeof(val)); 1450 1451 clean_http_headerbuf(&headerbuf); 1452 return (conn); 1453 ouch: 1454 serrno = errno; 1455 clean_http_headerbuf(&headerbuf); 1456 fetch_close(conn); 1457 errno = serrno; 1458 return (NULL); 1459 } 1460 1461 static struct url * 1462 http_get_proxy(struct url * url, const char *flags) 1463 { 1464 struct url *purl; 1465 char *p; 1466 1467 if (flags != NULL && strchr(flags, 'd') != NULL) 1468 return (NULL); 1469 if (fetch_no_proxy_match(url->host)) 1470 return (NULL); 1471 if (((p = getenv("HTTP_PROXY")) || (p = getenv("http_proxy"))) && 1472 *p && (purl = fetchParseURL(p))) { 1473 if (!*purl->scheme) 1474 strcpy(purl->scheme, SCHEME_HTTP); 1475 if (!purl->port) 1476 purl->port = fetch_default_proxy_port(purl->scheme); 1477 if (strcmp(purl->scheme, SCHEME_HTTP) == 0) 1478 return (purl); 1479 fetchFreeURL(purl); 1480 } 1481 return (NULL); 1482 } 1483 1484 static void 1485 http_print_html(FILE *out, FILE *in) 1486 { 1487 size_t len; 1488 char *line, *p, *q; 1489 int comment, tag; 1490 1491 comment = tag = 0; 1492 while ((line = fgetln(in, &len)) != NULL) { 1493 while (len && isspace((unsigned char)line[len - 1])) 1494 --len; 1495 for (p = q = line; q < line + len; ++q) { 1496 if (comment && *q == '-') { 1497 if (q + 2 < line + len && 1498 strcmp(q, "-->") == 0) { 1499 tag = comment = 0; 1500 q += 2; 1501 } 1502 } else if (tag && !comment && *q == '>') { 1503 p = q + 1; 1504 tag = 0; 1505 } else if (!tag && *q == '<') { 1506 if (q > p) 1507 fwrite(p, q - p, 1, out); 1508 tag = 1; 1509 if (q + 3 < line + len && 1510 strcmp(q, "<!--") == 0) { 1511 comment = 1; 1512 q += 3; 1513 } 1514 } 1515 } 1516 if (!tag && q > p) 1517 fwrite(p, q - p, 1, out); 1518 fputc('\n', out); 1519 } 1520 } 1521 1522 1523 /***************************************************************************** 1524 * Core 1525 */ 1526 1527 FILE * 1528 http_request(struct url *URL, const char *op, struct url_stat *us, 1529 struct url *purl, const char *flags) 1530 { 1531 1532 return (http_request_body(URL, op, us, purl, flags, NULL, NULL)); 1533 } 1534 1535 /* 1536 * Send a request and process the reply 1537 * 1538 * XXX This function is way too long, the do..while loop should be split 1539 * XXX off into a separate function. 1540 */ 1541 FILE * 1542 http_request_body(struct url *URL, const char *op, struct url_stat *us, 1543 struct url *purl, const char *flags, const char *content_type, 1544 const char *body) 1545 { 1546 char timebuf[80]; 1547 char hbuf[MAXHOSTNAMELEN + 7], *host; 1548 conn_t *conn; 1549 struct url *url, *new; 1550 int chunked, direct, ims, noredirect, verbose; 1551 int e, i, n, val; 1552 off_t offset, clength, length, size; 1553 time_t mtime; 1554 const char *p; 1555 FILE *f; 1556 hdr_t h; 1557 struct tm *timestruct; 1558 http_headerbuf_t headerbuf; 1559 http_auth_challenges_t server_challenges; 1560 http_auth_challenges_t proxy_challenges; 1561 size_t body_len; 1562 1563 /* The following calls don't allocate anything */ 1564 init_http_headerbuf(&headerbuf); 1565 init_http_auth_challenges(&server_challenges); 1566 init_http_auth_challenges(&proxy_challenges); 1567 1568 direct = CHECK_FLAG('d'); 1569 noredirect = CHECK_FLAG('A'); 1570 verbose = CHECK_FLAG('v'); 1571 ims = CHECK_FLAG('i'); 1572 1573 if (direct && purl) { 1574 fetchFreeURL(purl); 1575 purl = NULL; 1576 } 1577 1578 /* try the provided URL first */ 1579 url = URL; 1580 1581 n = MAX_REDIRECT; 1582 i = 0; 1583 1584 e = HTTP_PROTOCOL_ERROR; 1585 do { 1586 new = NULL; 1587 chunked = 0; 1588 offset = 0; 1589 clength = -1; 1590 length = -1; 1591 size = -1; 1592 mtime = 0; 1593 1594 /* check port */ 1595 if (!url->port) 1596 url->port = fetch_default_port(url->scheme); 1597 1598 /* were we redirected to an FTP URL? */ 1599 if (purl == NULL && strcmp(url->scheme, SCHEME_FTP) == 0) { 1600 if (strcmp(op, "GET") == 0) 1601 return (ftp_request(url, "RETR", us, purl, flags)); 1602 else if (strcmp(op, "HEAD") == 0) 1603 return (ftp_request(url, "STAT", us, purl, flags)); 1604 } 1605 1606 /* connect to server or proxy */ 1607 if ((conn = http_connect(url, purl, flags)) == NULL) 1608 goto ouch; 1609 1610 /* append port number only if necessary */ 1611 host = url->host; 1612 if (url->port != fetch_default_port(url->scheme)) { 1613 snprintf(hbuf, sizeof(hbuf), "%s:%d", host, url->port); 1614 host = hbuf; 1615 } 1616 1617 /* send request */ 1618 if (verbose) 1619 fetch_info("requesting %s://%s%s", 1620 url->scheme, host, url->doc); 1621 if (purl && strcmp(url->scheme, SCHEME_HTTPS) != 0) { 1622 http_cmd(conn, "%s %s://%s%s HTTP/1.1", 1623 op, url->scheme, host, url->doc); 1624 } else { 1625 http_cmd(conn, "%s %s HTTP/1.1", 1626 op, url->doc); 1627 } 1628 1629 if (ims && url->ims_time) { 1630 timestruct = gmtime((time_t *)&url->ims_time); 1631 (void)strftime(timebuf, 80, "%a, %d %b %Y %T GMT", 1632 timestruct); 1633 if (verbose) 1634 fetch_info("If-Modified-Since: %s", timebuf); 1635 http_cmd(conn, "If-Modified-Since: %s", timebuf); 1636 } 1637 /* virtual host */ 1638 http_cmd(conn, "Host: %s", host); 1639 1640 /* 1641 * Proxy authorization: we only send auth after we received 1642 * a 407 error. We do not first try basic anyway (changed 1643 * when support was added for digest-auth) 1644 */ 1645 if (purl && proxy_challenges.valid) { 1646 http_auth_params_t aparams; 1647 init_http_auth_params(&aparams); 1648 if (*purl->user || *purl->pwd) { 1649 aparams.user = strdup(purl->user); 1650 aparams.password = strdup(purl->pwd); 1651 } else if ((p = getenv("HTTP_PROXY_AUTH")) != NULL && 1652 *p != '\0') { 1653 if (http_authfromenv(p, &aparams) < 0) { 1654 http_seterr(HTTP_NEED_PROXY_AUTH); 1655 goto ouch; 1656 } 1657 } else if (fetch_netrc_auth(purl) == 0) { 1658 aparams.user = strdup(purl->user); 1659 aparams.password = strdup(purl->pwd); 1660 } 1661 http_authorize(conn, "Proxy-Authorization", 1662 &proxy_challenges, &aparams, url); 1663 clean_http_auth_params(&aparams); 1664 } 1665 1666 /* 1667 * Server authorization: we never send "a priori" 1668 * Basic auth, which used to be done if user/pass were 1669 * set in the url. This would be weird because we'd send the 1670 * password in the clear even if Digest is finally to be 1671 * used (it would have made more sense for the 1672 * pre-digest version to do this when Basic was specified 1673 * in the environment) 1674 */ 1675 if (server_challenges.valid) { 1676 http_auth_params_t aparams; 1677 init_http_auth_params(&aparams); 1678 if (*url->user || *url->pwd) { 1679 aparams.user = strdup(url->user); 1680 aparams.password = strdup(url->pwd); 1681 } else if ((p = getenv("HTTP_AUTH")) != NULL && 1682 *p != '\0') { 1683 if (http_authfromenv(p, &aparams) < 0) { 1684 http_seterr(HTTP_NEED_AUTH); 1685 goto ouch; 1686 } 1687 } else if (fetch_netrc_auth(url) == 0) { 1688 aparams.user = strdup(url->user); 1689 aparams.password = strdup(url->pwd); 1690 } else if (fetchAuthMethod && 1691 fetchAuthMethod(url) == 0) { 1692 aparams.user = strdup(url->user); 1693 aparams.password = strdup(url->pwd); 1694 } else { 1695 http_seterr(HTTP_NEED_AUTH); 1696 goto ouch; 1697 } 1698 http_authorize(conn, "Authorization", 1699 &server_challenges, &aparams, url); 1700 clean_http_auth_params(&aparams); 1701 } 1702 1703 /* other headers */ 1704 if ((p = getenv("HTTP_ACCEPT")) != NULL) { 1705 if (*p != '\0') 1706 http_cmd(conn, "Accept: %s", p); 1707 } else { 1708 http_cmd(conn, "Accept: */*"); 1709 } 1710 if ((p = getenv("HTTP_REFERER")) != NULL && *p != '\0') { 1711 if (strcasecmp(p, "auto") == 0) 1712 http_cmd(conn, "Referer: %s://%s%s", 1713 url->scheme, host, url->doc); 1714 else 1715 http_cmd(conn, "Referer: %s", p); 1716 } 1717 if ((p = getenv("HTTP_USER_AGENT")) != NULL) { 1718 /* no User-Agent if defined but empty */ 1719 if (*p != '\0') 1720 http_cmd(conn, "User-Agent: %s", p); 1721 } else { 1722 /* default User-Agent */ 1723 http_cmd(conn, "User-Agent: %s " _LIBFETCH_VER, 1724 getprogname()); 1725 } 1726 if (url->offset > 0) 1727 http_cmd(conn, "Range: bytes=%lld-", (long long)url->offset); 1728 http_cmd(conn, "Connection: close"); 1729 1730 if (body) { 1731 body_len = strlen(body); 1732 http_cmd(conn, "Content-Length: %zu", body_len); 1733 if (content_type != NULL) 1734 http_cmd(conn, "Content-Type: %s", content_type); 1735 } 1736 1737 http_cmd(conn, ""); 1738 1739 if (body) 1740 fetch_write(conn, body, body_len); 1741 1742 /* 1743 * Force the queued request to be dispatched. Normally, one 1744 * would do this with shutdown(2) but squid proxies can be 1745 * configured to disallow such half-closed connections. To 1746 * be compatible with such configurations, fiddle with socket 1747 * options to force the pending data to be written. 1748 */ 1749 val = 0; 1750 setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, 1751 sizeof(val)); 1752 val = 1; 1753 setsockopt(conn->sd, IPPROTO_TCP, TCP_NODELAY, &val, 1754 sizeof(val)); 1755 1756 /* get reply */ 1757 switch (http_get_reply(conn)) { 1758 case HTTP_OK: 1759 case HTTP_PARTIAL: 1760 case HTTP_NOT_MODIFIED: 1761 /* fine */ 1762 break; 1763 case HTTP_MOVED_PERM: 1764 case HTTP_MOVED_TEMP: 1765 case HTTP_TEMP_REDIRECT: 1766 case HTTP_PERM_REDIRECT: 1767 case HTTP_SEE_OTHER: 1768 case HTTP_USE_PROXY: 1769 /* 1770 * Not so fine, but we still have to read the 1771 * headers to get the new location. 1772 */ 1773 break; 1774 case HTTP_NEED_AUTH: 1775 if (server_challenges.valid) { 1776 /* 1777 * We already sent out authorization code, 1778 * so there's nothing more we can do. 1779 */ 1780 http_seterr(conn->err); 1781 goto ouch; 1782 } 1783 /* try again, but send the password this time */ 1784 if (verbose) 1785 fetch_info("server requires authorization"); 1786 break; 1787 case HTTP_NEED_PROXY_AUTH: 1788 if (proxy_challenges.valid) { 1789 /* 1790 * We already sent our proxy 1791 * authorization code, so there's 1792 * nothing more we can do. */ 1793 http_seterr(conn->err); 1794 goto ouch; 1795 } 1796 /* try again, but send the password this time */ 1797 if (verbose) 1798 fetch_info("proxy requires authorization"); 1799 break; 1800 case HTTP_BAD_RANGE: 1801 /* 1802 * This can happen if we ask for 0 bytes because 1803 * we already have the whole file. Consider this 1804 * a success for now, and check sizes later. 1805 */ 1806 break; 1807 case HTTP_PROTOCOL_ERROR: 1808 /* fall through */ 1809 case -1: 1810 fetch_syserr(); 1811 goto ouch; 1812 default: 1813 http_seterr(conn->err); 1814 if (!verbose) 1815 goto ouch; 1816 /* fall through so we can get the full error message */ 1817 } 1818 1819 /* get headers. http_next_header expects one line readahead */ 1820 if (fetch_getln(conn) == -1) { 1821 fetch_syserr(); 1822 goto ouch; 1823 } 1824 do { 1825 switch ((h = http_next_header(conn, &headerbuf, &p))) { 1826 case hdr_syserror: 1827 fetch_syserr(); 1828 goto ouch; 1829 case hdr_error: 1830 http_seterr(HTTP_PROTOCOL_ERROR); 1831 goto ouch; 1832 case hdr_content_length: 1833 http_parse_length(p, &clength); 1834 break; 1835 case hdr_content_range: 1836 http_parse_range(p, &offset, &length, &size); 1837 break; 1838 case hdr_last_modified: 1839 http_parse_mtime(p, &mtime); 1840 break; 1841 case hdr_location: 1842 if (!HTTP_REDIRECT(conn->err)) 1843 break; 1844 /* 1845 * if the A flag is set, we don't follow 1846 * temporary redirects. 1847 */ 1848 if (noredirect && 1849 conn->err != HTTP_MOVED_PERM && 1850 conn->err != HTTP_PERM_REDIRECT && 1851 conn->err != HTTP_USE_PROXY) { 1852 n = 1; 1853 break; 1854 } 1855 if (new) 1856 free(new); 1857 if (verbose) 1858 fetch_info("%d redirect to %s", 1859 conn->err, p); 1860 if (*p == '/') 1861 /* absolute path */ 1862 new = fetchMakeURL(url->scheme, url->host, 1863 url->port, p, url->user, url->pwd); 1864 else 1865 new = fetchParseURL(p); 1866 if (new == NULL) { 1867 /* XXX should set an error code */ 1868 DEBUGF("failed to parse new URL\n"); 1869 goto ouch; 1870 } 1871 1872 /* Only copy credentials if the host matches */ 1873 if (strcmp(new->host, url->host) == 0 && 1874 !*new->user && !*new->pwd) { 1875 strcpy(new->user, url->user); 1876 strcpy(new->pwd, url->pwd); 1877 } 1878 new->offset = url->offset; 1879 new->length = url->length; 1880 new->ims_time = url->ims_time; 1881 break; 1882 case hdr_transfer_encoding: 1883 /* XXX weak test*/ 1884 chunked = (strcasecmp(p, "chunked") == 0); 1885 break; 1886 case hdr_www_authenticate: 1887 if (conn->err != HTTP_NEED_AUTH) 1888 break; 1889 if (http_parse_authenticate(p, &server_challenges) == 0) 1890 ++n; 1891 break; 1892 case hdr_proxy_authenticate: 1893 if (conn->err != HTTP_NEED_PROXY_AUTH) 1894 break; 1895 if (http_parse_authenticate(p, &proxy_challenges) == 0) 1896 ++n; 1897 break; 1898 case hdr_end: 1899 /* fall through */ 1900 case hdr_unknown: 1901 /* ignore */ 1902 break; 1903 } 1904 } while (h > hdr_end); 1905 1906 /* we need to provide authentication */ 1907 if (conn->err == HTTP_NEED_AUTH || 1908 conn->err == HTTP_NEED_PROXY_AUTH) { 1909 e = conn->err; 1910 if ((conn->err == HTTP_NEED_AUTH && 1911 !server_challenges.valid) || 1912 (conn->err == HTTP_NEED_PROXY_AUTH && 1913 !proxy_challenges.valid)) { 1914 /* 401/7 but no www/proxy-authenticate ?? */ 1915 DEBUGF("%03d without auth header\n", conn->err); 1916 goto ouch; 1917 } 1918 fetch_close(conn); 1919 conn = NULL; 1920 continue; 1921 } 1922 1923 /* requested range not satisfiable */ 1924 if (conn->err == HTTP_BAD_RANGE) { 1925 if (url->offset > 0 && url->length == 0) { 1926 /* asked for 0 bytes; fake it */ 1927 offset = url->offset; 1928 clength = -1; 1929 conn->err = HTTP_OK; 1930 break; 1931 } else { 1932 http_seterr(conn->err); 1933 goto ouch; 1934 } 1935 } 1936 1937 /* we have a hit or an error */ 1938 if (conn->err == HTTP_OK 1939 || conn->err == HTTP_NOT_MODIFIED 1940 || conn->err == HTTP_PARTIAL 1941 || HTTP_ERROR(conn->err)) 1942 break; 1943 1944 /* all other cases: we got a redirect */ 1945 e = conn->err; 1946 clean_http_auth_challenges(&server_challenges); 1947 fetch_close(conn); 1948 conn = NULL; 1949 if (!new) { 1950 DEBUGF("redirect with no new location\n"); 1951 break; 1952 } 1953 if (url != URL) 1954 fetchFreeURL(url); 1955 url = new; 1956 } while (++i < n); 1957 1958 /* we failed, or ran out of retries */ 1959 if (conn == NULL) { 1960 http_seterr(e); 1961 goto ouch; 1962 } 1963 1964 DEBUGF("offset %lld, length %lld, size %lld, clength %lld\n", 1965 (long long)offset, (long long)length, 1966 (long long)size, (long long)clength); 1967 1968 if (conn->err == HTTP_NOT_MODIFIED) { 1969 http_seterr(HTTP_NOT_MODIFIED); 1970 return (NULL); 1971 } 1972 1973 /* check for inconsistencies */ 1974 if (clength != -1 && length != -1 && clength != length) { 1975 http_seterr(HTTP_PROTOCOL_ERROR); 1976 goto ouch; 1977 } 1978 if (clength == -1) 1979 clength = length; 1980 if (clength != -1) 1981 length = offset + clength; 1982 if (length != -1 && size != -1 && length != size) { 1983 http_seterr(HTTP_PROTOCOL_ERROR); 1984 goto ouch; 1985 } 1986 if (size == -1) 1987 size = length; 1988 1989 /* fill in stats */ 1990 if (us) { 1991 us->size = size; 1992 us->atime = us->mtime = mtime; 1993 } 1994 1995 /* too far? */ 1996 if (URL->offset > 0 && offset > URL->offset) { 1997 http_seterr(HTTP_PROTOCOL_ERROR); 1998 goto ouch; 1999 } 2000 2001 /* report back real offset and size */ 2002 URL->offset = offset; 2003 URL->length = clength; 2004 2005 /* wrap it up in a FILE */ 2006 if ((f = http_funopen(conn, chunked)) == NULL) { 2007 fetch_syserr(); 2008 goto ouch; 2009 } 2010 2011 if (url != URL) 2012 fetchFreeURL(url); 2013 if (purl) 2014 fetchFreeURL(purl); 2015 2016 if (HTTP_ERROR(conn->err)) { 2017 http_print_html(stderr, f); 2018 fclose(f); 2019 f = NULL; 2020 } 2021 clean_http_headerbuf(&headerbuf); 2022 clean_http_auth_challenges(&server_challenges); 2023 clean_http_auth_challenges(&proxy_challenges); 2024 return (f); 2025 2026 ouch: 2027 if (url != URL) 2028 fetchFreeURL(url); 2029 if (purl) 2030 fetchFreeURL(purl); 2031 if (conn != NULL) 2032 fetch_close(conn); 2033 clean_http_headerbuf(&headerbuf); 2034 clean_http_auth_challenges(&server_challenges); 2035 clean_http_auth_challenges(&proxy_challenges); 2036 return (NULL); 2037 } 2038 2039 2040 /***************************************************************************** 2041 * Entry points 2042 */ 2043 2044 /* 2045 * Retrieve and stat a file by HTTP 2046 */ 2047 FILE * 2048 fetchXGetHTTP(struct url *URL, struct url_stat *us, const char *flags) 2049 { 2050 return (http_request(URL, "GET", us, http_get_proxy(URL, flags), flags)); 2051 } 2052 2053 /* 2054 * Retrieve a file by HTTP 2055 */ 2056 FILE * 2057 fetchGetHTTP(struct url *URL, const char *flags) 2058 { 2059 return (fetchXGetHTTP(URL, NULL, flags)); 2060 } 2061 2062 /* 2063 * Store a file by HTTP 2064 */ 2065 FILE * 2066 fetchPutHTTP(struct url *URL __unused, const char *flags __unused) 2067 { 2068 warnx("fetchPutHTTP(): not implemented"); 2069 return (NULL); 2070 } 2071 2072 /* 2073 * Get an HTTP document's metadata 2074 */ 2075 int 2076 fetchStatHTTP(struct url *URL, struct url_stat *us, const char *flags) 2077 { 2078 FILE *f; 2079 2080 f = http_request(URL, "HEAD", us, http_get_proxy(URL, flags), flags); 2081 if (f == NULL) 2082 return (-1); 2083 fclose(f); 2084 return (0); 2085 } 2086 2087 /* 2088 * List a directory 2089 */ 2090 struct url_ent * 2091 fetchListHTTP(struct url *url __unused, const char *flags __unused) 2092 { 2093 warnx("fetchListHTTP(): not implemented"); 2094 return (NULL); 2095 } 2096 2097 /* 2098 * Arbitrary HTTP verb and content requests 2099 */ 2100 FILE * 2101 fetchReqHTTP(struct url *URL, const char *method, const char *flags, 2102 const char *content_type, const char *body) 2103 { 2104 2105 return (http_request_body(URL, method, NULL, http_get_proxy(URL, flags), 2106 flags, content_type, body)); 2107 } 2108