lib/libfetch/http.c

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