lib/libfetch/http.c

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