xref: /netbsd/external/bsd/fetch/dist/libfetch/http.c (revision 6550d01e)
1 /*	$NetBSD: http.c,v 1.1.1.7 2010/01/30 21:26:14 joerg Exp $	*/
2 /*-
3  * Copyright (c) 2000-2004 Dag-Erling Co�dan Sm�rgrav
4  * Copyright (c) 2003 Thomas Klausner <wiz@NetBSD.org>
5  * Copyright (c) 2008, 2009 Joerg Sonnenberger <joerg@NetBSD.org>
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer
13  *    in this position and unchanged.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. The name of the author may not be used to endorse or promote products
18  *    derived from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
24  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  *
31  * $FreeBSD: http.c,v 1.83 2008/02/06 11:39:55 des Exp $
32  */
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 #if defined(__linux__) || defined(__MINT__)
67 /* Keep this down to Linux or MiNT, it can create surprises elsewhere. */
68 #define _GNU_SOURCE
69 #endif
70 
71 /* Needed for gmtime_r on Interix */
72 #define _REENTRANT
73 
74 #if HAVE_CONFIG_H
75 #include "config.h"
76 #endif
77 #ifndef NETBSD
78 #include <nbcompat.h>
79 #endif
80 
81 #include <sys/types.h>
82 #include <sys/socket.h>
83 
84 #include <ctype.h>
85 #include <errno.h>
86 #include <locale.h>
87 #include <stdarg.h>
88 #ifndef NETBSD
89 #include <nbcompat/stdio.h>
90 #else
91 #include <stdio.h>
92 #endif
93 #include <stdlib.h>
94 #include <string.h>
95 #include <time.h>
96 #include <unistd.h>
97 
98 #include <netinet/in.h>
99 #include <netinet/tcp.h>
100 
101 #ifndef NETBSD
102 #include <nbcompat/netdb.h>
103 #else
104 #include <netdb.h>
105 #endif
106 
107 #include <arpa/inet.h>
108 
109 #include "fetch.h"
110 #include "common.h"
111 #include "httperr.h"
112 
113 /* Maximum number of redirects to follow */
114 #define MAX_REDIRECT 5
115 
116 /* Symbolic names for reply codes we care about */
117 #define HTTP_OK			200
118 #define HTTP_PARTIAL		206
119 #define HTTP_MOVED_PERM		301
120 #define HTTP_MOVED_TEMP		302
121 #define HTTP_SEE_OTHER		303
122 #define HTTP_NOT_MODIFIED	304
123 #define HTTP_TEMP_REDIRECT	307
124 #define HTTP_NEED_AUTH		401
125 #define HTTP_NEED_PROXY_AUTH	407
126 #define HTTP_BAD_RANGE		416
127 #define HTTP_PROTOCOL_ERROR	999
128 
129 #define HTTP_REDIRECT(xyz) ((xyz) == HTTP_MOVED_PERM \
130 			    || (xyz) == HTTP_MOVED_TEMP \
131 			    || (xyz) == HTTP_TEMP_REDIRECT \
132 			    || (xyz) == HTTP_SEE_OTHER)
133 
134 #define HTTP_ERROR(xyz) ((xyz) > 400 && (xyz) < 599)
135 
136 
137 /*****************************************************************************
138  * I/O functions for decoding chunked streams
139  */
140 
141 struct httpio
142 {
143 	conn_t		*conn;		/* connection */
144 	int		 chunked;	/* chunked mode */
145 	int		 keep_alive;	/* keep-alive mode */
146 	char		*buf;		/* chunk buffer */
147 	size_t		 bufsize;	/* size of chunk buffer */
148 	ssize_t		 buflen;	/* amount of data currently in buffer */
149 	int		 bufpos;	/* current read offset in buffer */
150 	int		 eof;		/* end-of-file flag */
151 	int		 error;		/* error flag */
152 	size_t		 chunksize;	/* remaining size of current chunk */
153 	off_t		 contentlength;	/* remaining size of the content */
154 };
155 
156 /*
157  * Get next chunk header
158  */
159 static int
160 http_new_chunk(struct httpio *io)
161 {
162 	char *p;
163 
164 	if (fetch_getln(io->conn) == -1)
165 		return (-1);
166 
167 	if (io->conn->buflen < 2 || !isxdigit((unsigned char)*io->conn->buf))
168 		return (-1);
169 
170 	for (p = io->conn->buf; *p && !isspace((unsigned char)*p); ++p) {
171 		if (*p == ';')
172 			break;
173 		if (!isxdigit((unsigned char)*p))
174 			return (-1);
175 		if (isdigit((unsigned char)*p)) {
176 			io->chunksize = io->chunksize * 16 +
177 			    *p - '0';
178 		} else {
179 			io->chunksize = io->chunksize * 16 +
180 			    10 + tolower((unsigned char)*p) - 'a';
181 		}
182 	}
183 
184 	return (io->chunksize);
185 }
186 
187 /*
188  * Grow the input buffer to at least len bytes
189  */
190 static int
191 http_growbuf(struct httpio *io, size_t len)
192 {
193 	char *tmp;
194 
195 	if (io->bufsize >= len)
196 		return (0);
197 
198 	if ((tmp = realloc(io->buf, len)) == NULL)
199 		return (-1);
200 	io->buf = tmp;
201 	io->bufsize = len;
202 	return (0);
203 }
204 
205 /*
206  * Fill the input buffer, do chunk decoding on the fly
207  */
208 static int
209 http_fillbuf(struct httpio *io, size_t len)
210 {
211 	if (io->error)
212 		return (-1);
213 	if (io->eof)
214 		return (0);
215 
216 	if (io->contentlength >= 0 && (off_t)len > io->contentlength)
217 		len = io->contentlength;
218 
219 	if (io->chunked == 0) {
220 		if (http_growbuf(io, len) == -1)
221 			return (-1);
222 		if ((io->buflen = fetch_read(io->conn, io->buf, len)) == -1) {
223 			io->error = 1;
224 			return (-1);
225 		}
226 		if (io->contentlength)
227 			io->contentlength -= io->buflen;
228 		io->bufpos = 0;
229 		return (io->buflen);
230 	}
231 
232 	if (io->chunksize == 0) {
233 		switch (http_new_chunk(io)) {
234 		case -1:
235 			io->error = 1;
236 			return (-1);
237 		case 0:
238 			io->eof = 1;
239 			if (fetch_getln(io->conn) == -1)
240 				return (-1);
241 			return (0);
242 		}
243 	}
244 
245 	if (len > io->chunksize)
246 		len = io->chunksize;
247 	if (http_growbuf(io, len) == -1)
248 		return (-1);
249 	if ((io->buflen = fetch_read(io->conn, io->buf, len)) == -1) {
250 		io->error = 1;
251 		return (-1);
252 	}
253 	io->chunksize -= io->buflen;
254 	if (io->contentlength >= 0)
255 		io->contentlength -= io->buflen;
256 
257 	if (io->chunksize == 0) {
258 		char endl[2];
259 		ssize_t len2;
260 
261 		len2 = fetch_read(io->conn, endl, 2);
262 		if (len2 == 1 && fetch_read(io->conn, endl + 1, 1) != 1)
263 			return (-1);
264 		if (len2 == -1 || endl[0] != '\r' || endl[1] != '\n')
265 			return (-1);
266 	}
267 
268 	io->bufpos = 0;
269 
270 	return (io->buflen);
271 }
272 
273 /*
274  * Read function
275  */
276 static ssize_t
277 http_readfn(void *v, void *buf, size_t len)
278 {
279 	struct httpio *io = (struct httpio *)v;
280 	size_t l, pos;
281 
282 	if (io->error)
283 		return (-1);
284 	if (io->eof)
285 		return (0);
286 
287 	for (pos = 0; len > 0; pos += l, len -= l) {
288 		/* empty buffer */
289 		if (!io->buf || io->bufpos == io->buflen)
290 			if (http_fillbuf(io, len) < 1)
291 				break;
292 		l = io->buflen - io->bufpos;
293 		if (len < l)
294 			l = len;
295 		memcpy((char *)buf + pos, io->buf + io->bufpos, l);
296 		io->bufpos += l;
297 	}
298 
299 	if (!pos && io->error)
300 		return (-1);
301 	return (pos);
302 }
303 
304 /*
305  * Write function
306  */
307 static ssize_t
308 http_writefn(void *v, const void *buf, size_t len)
309 {
310 	struct httpio *io = (struct httpio *)v;
311 
312 	return (fetch_write(io->conn, buf, len));
313 }
314 
315 /*
316  * Close function
317  */
318 static void
319 http_closefn(void *v)
320 {
321 	struct httpio *io = (struct httpio *)v;
322 
323 	if (io->keep_alive) {
324 		int val;
325 
326 		val = 0;
327 		setsockopt(io->conn->sd, IPPROTO_TCP, TCP_NODELAY, &val,
328 			   sizeof(val));
329 			  fetch_cache_put(io->conn, fetch_close);
330 #ifdef TCP_NOPUSH
331 		val = 1;
332 		setsockopt(io->conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val,
333 		    sizeof(val));
334 #endif
335 	} else {
336 		fetch_close(io->conn);
337 	}
338 
339 	free(io->buf);
340 	free(io);
341 }
342 
343 /*
344  * Wrap a file descriptor up
345  */
346 static fetchIO *
347 http_funopen(conn_t *conn, int chunked, int keep_alive, off_t clength)
348 {
349 	struct httpio *io;
350 	fetchIO *f;
351 
352 	if ((io = calloc(1, sizeof(*io))) == NULL) {
353 		fetch_syserr();
354 		return (NULL);
355 	}
356 	io->conn = conn;
357 	io->chunked = chunked;
358 	io->contentlength = clength;
359 	io->keep_alive = keep_alive;
360 	f = fetchIO_unopen(io, http_readfn, http_writefn, http_closefn);
361 	if (f == NULL) {
362 		fetch_syserr();
363 		free(io);
364 		return (NULL);
365 	}
366 	return (f);
367 }
368 
369 
370 /*****************************************************************************
371  * Helper functions for talking to the server and parsing its replies
372  */
373 
374 /* Header types */
375 typedef enum {
376 	hdr_syserror = -2,
377 	hdr_error = -1,
378 	hdr_end = 0,
379 	hdr_unknown = 1,
380 	hdr_connection,
381 	hdr_content_length,
382 	hdr_content_range,
383 	hdr_last_modified,
384 	hdr_location,
385 	hdr_transfer_encoding,
386 	hdr_www_authenticate
387 } hdr_t;
388 
389 /* Names of interesting headers */
390 static struct {
391 	hdr_t		 num;
392 	const char	*name;
393 } hdr_names[] = {
394 	{ hdr_connection,		"Connection" },
395 	{ hdr_content_length,		"Content-Length" },
396 	{ hdr_content_range,		"Content-Range" },
397 	{ hdr_last_modified,		"Last-Modified" },
398 	{ hdr_location,			"Location" },
399 	{ hdr_transfer_encoding,	"Transfer-Encoding" },
400 	{ hdr_www_authenticate,		"WWW-Authenticate" },
401 	{ hdr_unknown,			NULL },
402 };
403 
404 /*
405  * Send a formatted line; optionally echo to terminal
406  */
407 static int
408 http_cmd(conn_t *conn, const char *fmt, ...)
409 {
410 	va_list ap;
411 	size_t len;
412 	char *msg;
413 	int r;
414 
415 	va_start(ap, fmt);
416 	len = vasprintf(&msg, fmt, ap);
417 	va_end(ap);
418 
419 	if (msg == NULL) {
420 		errno = ENOMEM;
421 		fetch_syserr();
422 		return (-1);
423 	}
424 
425 	r = fetch_write(conn, msg, len);
426 	free(msg);
427 
428 	if (r == -1) {
429 		fetch_syserr();
430 		return (-1);
431 	}
432 
433 	return (0);
434 }
435 
436 /*
437  * Get and parse status line
438  */
439 static int
440 http_get_reply(conn_t *conn)
441 {
442 	char *p;
443 
444 	if (fetch_getln(conn) == -1)
445 		return (-1);
446 	/*
447 	 * A valid status line looks like "HTTP/m.n xyz reason" where m
448 	 * and n are the major and minor protocol version numbers and xyz
449 	 * is the reply code.
450 	 * Unfortunately, there are servers out there (NCSA 1.5.1, to name
451 	 * just one) that do not send a version number, so we can't rely
452 	 * on finding one, but if we do, insist on it being 1.0 or 1.1.
453 	 * We don't care about the reason phrase.
454 	 */
455 	if (strncmp(conn->buf, "HTTP", 4) != 0)
456 		return (HTTP_PROTOCOL_ERROR);
457 	p = conn->buf + 4;
458 	if (*p == '/') {
459 		if (p[1] != '1' || p[2] != '.' || (p[3] != '0' && p[3] != '1'))
460 			return (HTTP_PROTOCOL_ERROR);
461 		p += 4;
462 	}
463 	if (*p != ' ' ||
464 	    !isdigit((unsigned char)p[1]) ||
465 	    !isdigit((unsigned char)p[2]) ||
466 	    !isdigit((unsigned char)p[3]))
467 		return (HTTP_PROTOCOL_ERROR);
468 
469 	conn->err = (p[1] - '0') * 100 + (p[2] - '0') * 10 + (p[3] - '0');
470 	return (conn->err);
471 }
472 
473 /*
474  * Check a header; if the type matches the given string, return a pointer
475  * to the beginning of the value.
476  */
477 static const char *
478 http_match(const char *str, const char *hdr)
479 {
480 	while (*str && *hdr &&
481 	    tolower((unsigned char)*str++) == tolower((unsigned char)*hdr++))
482 		/* nothing */;
483 	if (*str || *hdr != ':')
484 		return (NULL);
485 	while (*hdr && isspace((unsigned char)*++hdr))
486 		/* nothing */;
487 	return (hdr);
488 }
489 
490 /*
491  * Get the next header and return the appropriate symbolic code.
492  */
493 static hdr_t
494 http_next_header(conn_t *conn, const char **p)
495 {
496 	int i;
497 
498 	if (fetch_getln(conn) == -1)
499 		return (hdr_syserror);
500 	while (conn->buflen && isspace((unsigned char)conn->buf[conn->buflen - 1]))
501 		conn->buflen--;
502 	conn->buf[conn->buflen] = '\0';
503 	if (conn->buflen == 0)
504 		return (hdr_end);
505 	/*
506 	 * We could check for malformed headers but we don't really care.
507 	 * A valid header starts with a token immediately followed by a
508 	 * colon; a token is any sequence of non-control, non-whitespace
509 	 * characters except "()<>@,;:\\\"{}".
510 	 */
511 	for (i = 0; hdr_names[i].num != hdr_unknown; i++)
512 		if ((*p = http_match(hdr_names[i].name, conn->buf)) != NULL)
513 			return (hdr_names[i].num);
514 	return (hdr_unknown);
515 }
516 
517 /*
518  * Parse a last-modified header
519  */
520 static int
521 http_parse_mtime(const char *p, time_t *mtime)
522 {
523 	char locale[64], *r;
524 	struct tm tm;
525 
526 	strncpy(locale, setlocale(LC_TIME, NULL), sizeof(locale));
527 	setlocale(LC_TIME, "C");
528 	r = strptime(p, "%a, %d %b %Y %H:%M:%S GMT", &tm);
529 	/* XXX should add support for date-2 and date-3 */
530 	setlocale(LC_TIME, locale);
531 	if (r == NULL)
532 		return (-1);
533 	*mtime = timegm(&tm);
534 	return (0);
535 }
536 
537 /*
538  * Parse a content-length header
539  */
540 static int
541 http_parse_length(const char *p, off_t *length)
542 {
543 	off_t len;
544 
545 	for (len = 0; *p && isdigit((unsigned char)*p); ++p)
546 		len = len * 10 + (*p - '0');
547 	if (*p)
548 		return (-1);
549 	*length = len;
550 	return (0);
551 }
552 
553 /*
554  * Parse a content-range header
555  */
556 static int
557 http_parse_range(const char *p, off_t *offset, off_t *length, off_t *size)
558 {
559 	off_t first, last, len;
560 
561 	if (strncasecmp(p, "bytes ", 6) != 0)
562 		return (-1);
563 	p += 6;
564 	if (*p == '*') {
565 		first = last = -1;
566 		++p;
567 	} else {
568 		for (first = 0; *p && isdigit((unsigned char)*p); ++p)
569 			first = first * 10 + *p - '0';
570 		if (*p != '-')
571 			return (-1);
572 		for (last = 0, ++p; *p && isdigit((unsigned char)*p); ++p)
573 			last = last * 10 + *p - '0';
574 	}
575 	if (first > last || *p != '/')
576 		return (-1);
577 	for (len = 0, ++p; *p && isdigit((unsigned char)*p); ++p)
578 		len = len * 10 + *p - '0';
579 	if (*p || len < last - first + 1)
580 		return (-1);
581 	if (first == -1)
582 		*length = 0;
583 	else
584 		*length = last - first + 1;
585 	*offset = first;
586 	*size = len;
587 	return (0);
588 }
589 
590 
591 /*****************************************************************************
592  * Helper functions for authorization
593  */
594 
595 /*
596  * Base64 encoding
597  */
598 static char *
599 http_base64(const char *src)
600 {
601 	static const char base64[] =
602 	    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
603 	    "abcdefghijklmnopqrstuvwxyz"
604 	    "0123456789+/";
605 	char *str, *dst;
606 	size_t l;
607 	int t, r;
608 
609 	l = strlen(src);
610 	if ((str = malloc(((l + 2) / 3) * 4 + 1)) == NULL)
611 		return (NULL);
612 	dst = str;
613 	r = 0;
614 
615 	while (l >= 3) {
616 		t = (src[0] << 16) | (src[1] << 8) | src[2];
617 		dst[0] = base64[(t >> 18) & 0x3f];
618 		dst[1] = base64[(t >> 12) & 0x3f];
619 		dst[2] = base64[(t >> 6) & 0x3f];
620 		dst[3] = base64[(t >> 0) & 0x3f];
621 		src += 3; l -= 3;
622 		dst += 4; r += 4;
623 	}
624 
625 	switch (l) {
626 	case 2:
627 		t = (src[0] << 16) | (src[1] << 8);
628 		dst[0] = base64[(t >> 18) & 0x3f];
629 		dst[1] = base64[(t >> 12) & 0x3f];
630 		dst[2] = base64[(t >> 6) & 0x3f];
631 		dst[3] = '=';
632 		dst += 4;
633 		r += 4;
634 		break;
635 	case 1:
636 		t = src[0] << 16;
637 		dst[0] = base64[(t >> 18) & 0x3f];
638 		dst[1] = base64[(t >> 12) & 0x3f];
639 		dst[2] = dst[3] = '=';
640 		dst += 4;
641 		r += 4;
642 		break;
643 	case 0:
644 		break;
645 	}
646 
647 	*dst = 0;
648 	return (str);
649 }
650 
651 /*
652  * Encode username and password
653  */
654 static int
655 http_basic_auth(conn_t *conn, const char *hdr, const char *usr, const char *pwd)
656 {
657 	char *upw, *auth;
658 	int r;
659 
660 	if (asprintf(&upw, "%s:%s", usr, pwd) == -1)
661 		return (-1);
662 	auth = http_base64(upw);
663 	free(upw);
664 	if (auth == NULL)
665 		return (-1);
666 	r = http_cmd(conn, "%s: Basic %s\r\n", hdr, auth);
667 	free(auth);
668 	return (r);
669 }
670 
671 /*
672  * Send an authorization header
673  */
674 static int
675 http_authorize(conn_t *conn, const char *hdr, const char *p)
676 {
677 	/* basic authorization */
678 	if (strncasecmp(p, "basic:", 6) == 0) {
679 		char *user, *pwd, *str;
680 		int r;
681 
682 		/* skip realm */
683 		for (p += 6; *p && *p != ':'; ++p)
684 			/* nothing */ ;
685 		if (!*p || strchr(++p, ':') == NULL)
686 			return (-1);
687 		if ((str = strdup(p)) == NULL)
688 			return (-1); /* XXX */
689 		user = str;
690 		pwd = strchr(str, ':');
691 		*pwd++ = '\0';
692 		r = http_basic_auth(conn, hdr, user, pwd);
693 		free(str);
694 		return (r);
695 	}
696 	return (-1);
697 }
698 
699 
700 /*****************************************************************************
701  * Helper functions for connecting to a server or proxy
702  */
703 
704 /*
705  * Connect to the correct HTTP server or proxy.
706  */
707 static conn_t *
708 http_connect(struct url *URL, struct url *purl, const char *flags, int *cached)
709 {
710 	conn_t *conn;
711 	int af, verbose;
712 #ifdef TCP_NOPUSH
713 	int val;
714 #endif
715 
716 	*cached = 1;
717 
718 #ifdef INET6
719 	af = AF_UNSPEC;
720 #else
721 	af = AF_INET;
722 #endif
723 
724 	verbose = CHECK_FLAG('v');
725 	if (CHECK_FLAG('4'))
726 		af = AF_INET;
727 #ifdef INET6
728 	else if (CHECK_FLAG('6'))
729 		af = AF_INET6;
730 #endif
731 
732 	if (purl && strcasecmp(URL->scheme, SCHEME_HTTPS) != 0) {
733 		URL = purl;
734 	} else if (strcasecmp(URL->scheme, SCHEME_FTP) == 0) {
735 		/* can't talk http to an ftp server */
736 		/* XXX should set an error code */
737 		return (NULL);
738 	}
739 
740 	if ((conn = fetch_cache_get(URL, af)) != NULL) {
741 		*cached = 1;
742 		return (conn);
743 	}
744 
745 	if ((conn = fetch_connect(URL, af, verbose)) == NULL)
746 		/* fetch_connect() has already set an error code */
747 		return (NULL);
748 	if (strcasecmp(URL->scheme, SCHEME_HTTPS) == 0 &&
749 	    fetch_ssl(conn, verbose) == -1) {
750 		fetch_close(conn);
751 		/* grrr */
752 #ifdef EAUTH
753 		errno = EAUTH;
754 #else
755 		errno = EPERM;
756 #endif
757 		fetch_syserr();
758 		return (NULL);
759 	}
760 
761 #ifdef TCP_NOPUSH
762 	val = 1;
763 	setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val, sizeof(val));
764 #endif
765 
766 	return (conn);
767 }
768 
769 static struct url *
770 http_get_proxy(struct url * url, const char *flags)
771 {
772 	struct url *purl;
773 	char *p;
774 
775 	if (flags != NULL && strchr(flags, 'd') != NULL)
776 		return (NULL);
777 	if (fetch_no_proxy_match(url->host))
778 		return (NULL);
779 	if (((p = getenv("HTTP_PROXY")) || (p = getenv("http_proxy"))) &&
780 	    *p && (purl = fetchParseURL(p))) {
781 		if (!*purl->scheme)
782 			strcpy(purl->scheme, SCHEME_HTTP);
783 		if (!purl->port)
784 			purl->port = fetch_default_proxy_port(purl->scheme);
785 		if (strcasecmp(purl->scheme, SCHEME_HTTP) == 0)
786 			return (purl);
787 		fetchFreeURL(purl);
788 	}
789 	return (NULL);
790 }
791 
792 static void
793 set_if_modified_since(conn_t *conn, time_t last_modified)
794 {
795 	static const char weekdays[] = "SunMonTueWedThuFriSat";
796 	static const char months[] = "JanFebMarAprMayJunJulAugSepOctNovDec";
797 	struct tm tm;
798 	char buf[80];
799 	gmtime_r(&last_modified, &tm);
800 	snprintf(buf, sizeof(buf), "%.3s, %02d %.3s %4d %02d:%02d:%02d GMT",
801 	    weekdays + tm.tm_wday * 3, tm.tm_mday, months + tm.tm_mon * 3,
802 	    tm.tm_year + 1900, tm.tm_hour, tm.tm_min, tm.tm_sec);
803 	http_cmd(conn, "If-Modified-Since: %s\r\n", buf);
804 }
805 
806 
807 /*****************************************************************************
808  * Core
809  */
810 
811 /*
812  * Send a request and process the reply
813  *
814  * XXX This function is way too long, the do..while loop should be split
815  * XXX off into a separate function.
816  */
817 fetchIO *
818 http_request(struct url *URL, const char *op, struct url_stat *us,
819     struct url *purl, const char *flags)
820 {
821 	conn_t *conn;
822 	struct url *url, *new;
823 	int chunked, direct, if_modified_since, need_auth, noredirect;
824 	int keep_alive, verbose, cached;
825 	int e, i, n, val;
826 	off_t offset, clength, length, size;
827 	time_t mtime;
828 	const char *p;
829 	fetchIO *f;
830 	hdr_t h;
831 	char hbuf[URL_HOSTLEN + 7], *host;
832 
833 	direct = CHECK_FLAG('d');
834 	noredirect = CHECK_FLAG('A');
835 	verbose = CHECK_FLAG('v');
836 	if_modified_since = CHECK_FLAG('i');
837 	keep_alive = 0;
838 
839 	if (direct && purl) {
840 		fetchFreeURL(purl);
841 		purl = NULL;
842 	}
843 
844 	/* try the provided URL first */
845 	url = URL;
846 
847 	/* if the A flag is set, we only get one try */
848 	n = noredirect ? 1 : MAX_REDIRECT;
849 	i = 0;
850 
851 	e = HTTP_PROTOCOL_ERROR;
852 	need_auth = 0;
853 	do {
854 		new = NULL;
855 		chunked = 0;
856 		offset = 0;
857 		clength = -1;
858 		length = -1;
859 		size = -1;
860 		mtime = 0;
861 
862 		/* check port */
863 		if (!url->port)
864 			url->port = fetch_default_port(url->scheme);
865 
866 		/* were we redirected to an FTP URL? */
867 		if (purl == NULL && strcmp(url->scheme, SCHEME_FTP) == 0) {
868 			if (strcmp(op, "GET") == 0)
869 				return (ftp_request(url, "RETR", NULL, us, purl, flags));
870 			else if (strcmp(op, "HEAD") == 0)
871 				return (ftp_request(url, "STAT", NULL, us, purl, flags));
872 		}
873 
874 		/* connect to server or proxy */
875 		if ((conn = http_connect(url, purl, flags, &cached)) == NULL)
876 			goto ouch;
877 
878 		host = url->host;
879 #ifdef INET6
880 		if (strchr(url->host, ':')) {
881 			snprintf(hbuf, sizeof(hbuf), "[%s]", url->host);
882 			host = hbuf;
883 		}
884 #endif
885 		if (url->port != fetch_default_port(url->scheme)) {
886 			if (host != hbuf) {
887 				strcpy(hbuf, host);
888 				host = hbuf;
889 			}
890 			snprintf(hbuf + strlen(hbuf),
891 			    sizeof(hbuf) - strlen(hbuf), ":%d", url->port);
892 		}
893 
894 		/* send request */
895 		if (verbose)
896 			fetch_info("requesting %s://%s%s",
897 			    url->scheme, host, url->doc);
898 		if (purl) {
899 			http_cmd(conn, "%s %s://%s%s HTTP/1.1\r\n",
900 			    op, url->scheme, host, url->doc);
901 		} else {
902 			http_cmd(conn, "%s %s HTTP/1.1\r\n",
903 			    op, url->doc);
904 		}
905 
906 		if (if_modified_since && url->last_modified > 0)
907 			set_if_modified_since(conn, url->last_modified);
908 
909 		/* virtual host */
910 		http_cmd(conn, "Host: %s\r\n", host);
911 
912 		/* proxy authorization */
913 		if (purl) {
914 			if (*purl->user || *purl->pwd)
915 				http_basic_auth(conn, "Proxy-Authorization",
916 				    purl->user, purl->pwd);
917 			else if ((p = getenv("HTTP_PROXY_AUTH")) != NULL && *p != '\0')
918 				http_authorize(conn, "Proxy-Authorization", p);
919 		}
920 
921 		/* server authorization */
922 		if (need_auth || *url->user || *url->pwd) {
923 			if (*url->user || *url->pwd)
924 				http_basic_auth(conn, "Authorization", url->user, url->pwd);
925 			else if ((p = getenv("HTTP_AUTH")) != NULL && *p != '\0')
926 				http_authorize(conn, "Authorization", p);
927 			else if (fetchAuthMethod && fetchAuthMethod(url) == 0) {
928 				http_basic_auth(conn, "Authorization", url->user, url->pwd);
929 			} else {
930 				http_seterr(HTTP_NEED_AUTH);
931 				goto ouch;
932 			}
933 		}
934 
935 		/* other headers */
936 		if ((p = getenv("HTTP_REFERER")) != NULL && *p != '\0') {
937 			if (strcasecmp(p, "auto") == 0)
938 				http_cmd(conn, "Referer: %s://%s%s\r\n",
939 				    url->scheme, host, url->doc);
940 			else
941 				http_cmd(conn, "Referer: %s\r\n", p);
942 		}
943 		if ((p = getenv("HTTP_USER_AGENT")) != NULL && *p != '\0')
944 			http_cmd(conn, "User-Agent: %s\r\n", p);
945 		else
946 			http_cmd(conn, "User-Agent: %s\r\n", _LIBFETCH_VER);
947 		if (url->offset > 0)
948 			http_cmd(conn, "Range: bytes=%lld-\r\n", (long long)url->offset);
949 		http_cmd(conn, "\r\n");
950 
951 		/*
952 		 * Force the queued request to be dispatched.  Normally, one
953 		 * would do this with shutdown(2) but squid proxies can be
954 		 * configured to disallow such half-closed connections.  To
955 		 * be compatible with such configurations, fiddle with socket
956 		 * options to force the pending data to be written.
957 		 */
958 #ifdef TCP_NOPUSH
959 		val = 0;
960 		setsockopt(conn->sd, IPPROTO_TCP, TCP_NOPUSH, &val,
961 			   sizeof(val));
962 #endif
963 		val = 1;
964 		setsockopt(conn->sd, IPPROTO_TCP, TCP_NODELAY, &val,
965 			   sizeof(val));
966 
967 		/* get reply */
968 		switch (http_get_reply(conn)) {
969 		case HTTP_OK:
970 		case HTTP_PARTIAL:
971 		case HTTP_NOT_MODIFIED:
972 			/* fine */
973 			break;
974 		case HTTP_MOVED_PERM:
975 		case HTTP_MOVED_TEMP:
976 		case HTTP_SEE_OTHER:
977 			/*
978 			 * Not so fine, but we still have to read the
979 			 * headers to get the new location.
980 			 */
981 			break;
982 		case HTTP_NEED_AUTH:
983 			if (need_auth) {
984 				/*
985 				 * We already sent out authorization code,
986 				 * so there's nothing more we can do.
987 				 */
988 				http_seterr(conn->err);
989 				goto ouch;
990 			}
991 			/* try again, but send the password this time */
992 			if (verbose)
993 				fetch_info("server requires authorization");
994 			break;
995 		case HTTP_NEED_PROXY_AUTH:
996 			/*
997 			 * If we're talking to a proxy, we already sent
998 			 * our proxy authorization code, so there's
999 			 * nothing more we can do.
1000 			 */
1001 			http_seterr(conn->err);
1002 			goto ouch;
1003 		case HTTP_BAD_RANGE:
1004 			/*
1005 			 * This can happen if we ask for 0 bytes because
1006 			 * we already have the whole file.  Consider this
1007 			 * a success for now, and check sizes later.
1008 			 */
1009 			break;
1010 		case HTTP_PROTOCOL_ERROR:
1011 			/* fall through */
1012 		case -1:
1013 			--i;
1014 			if (cached)
1015 				continue;
1016 			fetch_syserr();
1017 			goto ouch;
1018 		default:
1019 			http_seterr(conn->err);
1020 			if (!verbose)
1021 				goto ouch;
1022 			/* fall through so we can get the full error message */
1023 		}
1024 
1025 		/* get headers */
1026 		do {
1027 			switch ((h = http_next_header(conn, &p))) {
1028 			case hdr_syserror:
1029 				fetch_syserr();
1030 				goto ouch;
1031 			case hdr_error:
1032 				http_seterr(HTTP_PROTOCOL_ERROR);
1033 				goto ouch;
1034 			case hdr_connection:
1035 				/* XXX too weak? */
1036 				keep_alive = (strcasecmp(p, "keep-alive") == 0);
1037 				break;
1038 			case hdr_content_length:
1039 				http_parse_length(p, &clength);
1040 				break;
1041 			case hdr_content_range:
1042 				http_parse_range(p, &offset, &length, &size);
1043 				break;
1044 			case hdr_last_modified:
1045 				http_parse_mtime(p, &mtime);
1046 				break;
1047 			case hdr_location:
1048 				if (!HTTP_REDIRECT(conn->err))
1049 					break;
1050 				if (new)
1051 					free(new);
1052 				if (verbose)
1053 					fetch_info("%d redirect to %s", conn->err, p);
1054 				if (*p == '/')
1055 					/* absolute path */
1056 					new = fetchMakeURL(url->scheme, url->host, url->port, p,
1057 					    url->user, url->pwd);
1058 				else
1059 					new = fetchParseURL(p);
1060 				if (new == NULL) {
1061 					/* XXX should set an error code */
1062 					goto ouch;
1063 				}
1064 				if (!*new->user && !*new->pwd) {
1065 					strcpy(new->user, url->user);
1066 					strcpy(new->pwd, url->pwd);
1067 				}
1068 				new->offset = url->offset;
1069 				new->length = url->length;
1070 				break;
1071 			case hdr_transfer_encoding:
1072 				/* XXX weak test*/
1073 				chunked = (strcasecmp(p, "chunked") == 0);
1074 				break;
1075 			case hdr_www_authenticate:
1076 				if (conn->err != HTTP_NEED_AUTH)
1077 					break;
1078 				/* if we were smarter, we'd check the method and realm */
1079 				break;
1080 			case hdr_end:
1081 				/* fall through */
1082 			case hdr_unknown:
1083 				/* ignore */
1084 				break;
1085 			}
1086 		} while (h > hdr_end);
1087 
1088 		/* we need to provide authentication */
1089 		if (conn->err == HTTP_NEED_AUTH) {
1090 			e = conn->err;
1091 			need_auth = 1;
1092 			fetch_close(conn);
1093 			conn = NULL;
1094 			continue;
1095 		}
1096 
1097 		/* requested range not satisfiable */
1098 		if (conn->err == HTTP_BAD_RANGE) {
1099 			if (url->offset == size && url->length == 0) {
1100 				/* asked for 0 bytes; fake it */
1101 				offset = url->offset;
1102 				conn->err = HTTP_OK;
1103 				break;
1104 			} else {
1105 				http_seterr(conn->err);
1106 				goto ouch;
1107 			}
1108 		}
1109 
1110 		/* we have a hit or an error */
1111 		if (conn->err == HTTP_OK ||
1112 		    conn->err == HTTP_PARTIAL ||
1113 		    conn->err == HTTP_NOT_MODIFIED ||
1114 		    HTTP_ERROR(conn->err))
1115 			break;
1116 
1117 		/* all other cases: we got a redirect */
1118 		e = conn->err;
1119 		need_auth = 0;
1120 		fetch_close(conn);
1121 		conn = NULL;
1122 		if (!new)
1123 			break;
1124 		if (url != URL)
1125 			fetchFreeURL(url);
1126 		url = new;
1127 	} while (++i < n);
1128 
1129 	/* we failed, or ran out of retries */
1130 	if (conn == NULL) {
1131 		http_seterr(e);
1132 		goto ouch;
1133 	}
1134 
1135 	/* check for inconsistencies */
1136 	if (clength != -1 && length != -1 && clength != length) {
1137 		http_seterr(HTTP_PROTOCOL_ERROR);
1138 		goto ouch;
1139 	}
1140 	if (clength == -1)
1141 		clength = length;
1142 	if (clength != -1)
1143 		length = offset + clength;
1144 	if (length != -1 && size != -1 && length != size) {
1145 		http_seterr(HTTP_PROTOCOL_ERROR);
1146 		goto ouch;
1147 	}
1148 	if (size == -1)
1149 		size = length;
1150 
1151 	/* fill in stats */
1152 	if (us) {
1153 		us->size = size;
1154 		us->atime = us->mtime = mtime;
1155 	}
1156 
1157 	/* too far? */
1158 	if (URL->offset > 0 && offset > URL->offset) {
1159 		http_seterr(HTTP_PROTOCOL_ERROR);
1160 		goto ouch;
1161 	}
1162 
1163 	/* report back real offset and size */
1164 	URL->offset = offset;
1165 	URL->length = clength;
1166 
1167 	if (clength == -1 && !chunked)
1168 		keep_alive = 0;
1169 
1170 	if (conn->err == HTTP_NOT_MODIFIED) {
1171 		http_seterr(HTTP_NOT_MODIFIED);
1172 		if (keep_alive) {
1173 			fetch_cache_put(conn, fetch_close);
1174 			conn = NULL;
1175 		}
1176 		goto ouch;
1177 	}
1178 
1179 	/* wrap it up in a fetchIO */
1180 	if ((f = http_funopen(conn, chunked, keep_alive, clength)) == NULL) {
1181 		fetch_syserr();
1182 		goto ouch;
1183 	}
1184 
1185 	if (url != URL)
1186 		fetchFreeURL(url);
1187 	if (purl)
1188 		fetchFreeURL(purl);
1189 
1190 	if (HTTP_ERROR(conn->err)) {
1191 
1192 		if (keep_alive) {
1193 			char buf[512];
1194 			do {
1195 			} while (fetchIO_read(f, buf, sizeof(buf)) > 0);
1196 		}
1197 
1198 		fetchIO_close(f);
1199 		f = NULL;
1200 	}
1201 
1202 	return (f);
1203 
1204 ouch:
1205 	if (url != URL)
1206 		fetchFreeURL(url);
1207 	if (purl)
1208 		fetchFreeURL(purl);
1209 	if (conn != NULL)
1210 		fetch_close(conn);
1211 	return (NULL);
1212 }
1213 
1214 
1215 /*****************************************************************************
1216  * Entry points
1217  */
1218 
1219 /*
1220  * Retrieve and stat a file by HTTP
1221  */
1222 fetchIO *
1223 fetchXGetHTTP(struct url *URL, struct url_stat *us, const char *flags)
1224 {
1225 	return (http_request(URL, "GET", us, http_get_proxy(URL, flags), flags));
1226 }
1227 
1228 /*
1229  * Retrieve a file by HTTP
1230  */
1231 fetchIO *
1232 fetchGetHTTP(struct url *URL, const char *flags)
1233 {
1234 	return (fetchXGetHTTP(URL, NULL, flags));
1235 }
1236 
1237 /*
1238  * Store a file by HTTP
1239  */
1240 fetchIO *
1241 fetchPutHTTP(struct url *URL, const char *flags)
1242 {
1243 	fprintf(stderr, "fetchPutHTTP(): not implemented\n");
1244 	return (NULL);
1245 }
1246 
1247 /*
1248  * Get an HTTP document's metadata
1249  */
1250 int
1251 fetchStatHTTP(struct url *URL, struct url_stat *us, const char *flags)
1252 {
1253 	fetchIO *f;
1254 
1255 	f = http_request(URL, "HEAD", us, http_get_proxy(URL, flags), flags);
1256 	if (f == NULL)
1257 		return (-1);
1258 	fetchIO_close(f);
1259 	return (0);
1260 }
1261 
1262 enum http_states {
1263 	ST_NONE,
1264 	ST_LT,
1265 	ST_LTA,
1266 	ST_TAGA,
1267 	ST_H,
1268 	ST_R,
1269 	ST_E,
1270 	ST_F,
1271 	ST_HREF,
1272 	ST_HREFQ,
1273 	ST_TAG,
1274 	ST_TAGAX,
1275 	ST_TAGAQ
1276 };
1277 
1278 struct index_parser {
1279 	struct url_list *ue;
1280 	struct url *url;
1281 	enum http_states state;
1282 };
1283 
1284 static ssize_t
1285 parse_index(struct index_parser *parser, const char *buf, size_t len)
1286 {
1287 	char *end_attr, p = *buf;
1288 
1289 	switch (parser->state) {
1290 	case ST_NONE:
1291 		/* Plain text, not in markup */
1292 		if (p == '<')
1293 			parser->state = ST_LT;
1294 		return 1;
1295 	case ST_LT:
1296 		/* In tag -- "<" already found */
1297 		if (p == '>')
1298 			parser->state = ST_NONE;
1299 		else if (p == 'a' || p == 'A')
1300 			parser->state = ST_LTA;
1301 		else if (!isspace((unsigned char)p))
1302 			parser->state = ST_TAG;
1303 		return 1;
1304 	case ST_LTA:
1305 		/* In tag -- "<a" already found */
1306 		if (p == '>')
1307 			parser->state = ST_NONE;
1308 		else if (p == '"')
1309 			parser->state = ST_TAGAQ;
1310 		else if (isspace((unsigned char)p))
1311 			parser->state = ST_TAGA;
1312 		else
1313 			parser->state = ST_TAG;
1314 		return 1;
1315 	case ST_TAG:
1316 		/* In tag, but not "<a" -- disregard */
1317 		if (p == '>')
1318 			parser->state = ST_NONE;
1319 		return 1;
1320 	case ST_TAGA:
1321 		/* In a-tag -- "<a " already found */
1322 		if (p == '>')
1323 			parser->state = ST_NONE;
1324 		else if (p == '"')
1325 			parser->state = ST_TAGAQ;
1326 		else if (p == 'h' || p == 'H')
1327 			parser->state = ST_H;
1328 		else if (!isspace((unsigned char)p))
1329 			parser->state = ST_TAGAX;
1330 		return 1;
1331 	case ST_TAGAX:
1332 		/* In unknown keyword in a-tag */
1333 		if (p == '>')
1334 			parser->state = ST_NONE;
1335 		else if (p == '"')
1336 			parser->state = ST_TAGAQ;
1337 		else if (isspace((unsigned char)p))
1338 			parser->state = ST_TAGA;
1339 		return 1;
1340 	case ST_TAGAQ:
1341 		/* In a-tag, unknown argument for keys. */
1342 		if (p == '>')
1343 			parser->state = ST_NONE;
1344 		else if (p == '"')
1345 			parser->state = ST_TAGA;
1346 		return 1;
1347 	case ST_H:
1348 		/* In a-tag -- "<a h" already found */
1349 		if (p == '>')
1350 			parser->state = ST_NONE;
1351 		else if (p == '"')
1352 			parser->state = ST_TAGAQ;
1353 		else if (p == 'r' || p == 'R')
1354 			parser->state = ST_R;
1355 		else if (isspace((unsigned char)p))
1356 			parser->state = ST_TAGA;
1357 		else
1358 			parser->state = ST_TAGAX;
1359 		return 1;
1360 	case ST_R:
1361 		/* In a-tag -- "<a hr" already found */
1362 		if (p == '>')
1363 			parser->state = ST_NONE;
1364 		else if (p == '"')
1365 			parser->state = ST_TAGAQ;
1366 		else if (p == 'e' || p == 'E')
1367 			parser->state = ST_E;
1368 		else if (isspace((unsigned char)p))
1369 			parser->state = ST_TAGA;
1370 		else
1371 			parser->state = ST_TAGAX;
1372 		return 1;
1373 	case ST_E:
1374 		/* In a-tag -- "<a hre" already found */
1375 		if (p == '>')
1376 			parser->state = ST_NONE;
1377 		else if (p == '"')
1378 			parser->state = ST_TAGAQ;
1379 		else if (p == 'f' || p == 'F')
1380 			parser->state = ST_F;
1381 		else if (isspace((unsigned char)p))
1382 			parser->state = ST_TAGA;
1383 		else
1384 			parser->state = ST_TAGAX;
1385 		return 1;
1386 	case ST_F:
1387 		/* In a-tag -- "<a href" already found */
1388 		if (p == '>')
1389 			parser->state = ST_NONE;
1390 		else if (p == '"')
1391 			parser->state = ST_TAGAQ;
1392 		else if (p == '=')
1393 			parser->state = ST_HREF;
1394 		else if (!isspace((unsigned char)p))
1395 			parser->state = ST_TAGAX;
1396 		return 1;
1397 	case ST_HREF:
1398 		/* In a-tag -- "<a href=" already found */
1399 		if (p == '>')
1400 			parser->state = ST_NONE;
1401 		else if (p == '"')
1402 			parser->state = ST_HREFQ;
1403 		else if (!isspace((unsigned char)p))
1404 			parser->state = ST_TAGA;
1405 		return 1;
1406 	case ST_HREFQ:
1407 		/* In href of the a-tag */
1408 		end_attr = memchr(buf, '"', len);
1409 		if (end_attr == NULL)
1410 			return 0;
1411 		*end_attr = '\0';
1412 		parser->state = ST_TAGA;
1413 		if (fetch_add_entry(parser->ue, parser->url, buf, 1))
1414 			return -1;
1415 		return end_attr + 1 - buf;
1416 	}
1417 	/* NOTREACHED */
1418 	abort();
1419 }
1420 
1421 struct http_index_cache {
1422 	struct http_index_cache *next;
1423 	struct url *location;
1424 	struct url_list ue;
1425 };
1426 
1427 static struct http_index_cache *index_cache;
1428 
1429 /*
1430  * List a directory
1431  */
1432 int
1433 fetchListHTTP(struct url_list *ue, struct url *url, const char *pattern, const char *flags)
1434 {
1435 	fetchIO *f;
1436 	char buf[2 * PATH_MAX];
1437 	size_t buf_len, sum_processed;
1438 	ssize_t read_len, processed;
1439 	struct index_parser state;
1440 	struct http_index_cache *cache = NULL;
1441 	int do_cache, ret;
1442 
1443 	do_cache = CHECK_FLAG('c');
1444 
1445 	if (do_cache) {
1446 		for (cache = index_cache; cache != NULL; cache = cache->next) {
1447 			if (strcmp(cache->location->scheme, url->scheme))
1448 				continue;
1449 			if (strcmp(cache->location->user, url->user))
1450 				continue;
1451 			if (strcmp(cache->location->pwd, url->pwd))
1452 				continue;
1453 			if (strcmp(cache->location->host, url->host))
1454 				continue;
1455 			if (cache->location->port != url->port)
1456 				continue;
1457 			if (strcmp(cache->location->doc, url->doc))
1458 				continue;
1459 			return fetchAppendURLList(ue, &cache->ue);
1460 		}
1461 
1462 		cache = malloc(sizeof(*cache));
1463 		fetchInitURLList(&cache->ue);
1464 		cache->location = fetchCopyURL(url);
1465 	}
1466 
1467 	f = fetchGetHTTP(url, flags);
1468 	if (f == NULL) {
1469 		if (do_cache) {
1470 			fetchFreeURLList(&cache->ue);
1471 			fetchFreeURL(cache->location);
1472 			free(cache);
1473 		}
1474 		return -1;
1475 	}
1476 
1477 	state.url = url;
1478 	state.state = ST_NONE;
1479 	if (do_cache) {
1480 		state.ue = &cache->ue;
1481 	} else {
1482 		state.ue = ue;
1483 	}
1484 
1485 	buf_len = 0;
1486 
1487 	while ((read_len = fetchIO_read(f, buf + buf_len, sizeof(buf) - buf_len)) > 0) {
1488 		buf_len += read_len;
1489 		sum_processed = 0;
1490 		do {
1491 			processed = parse_index(&state, buf + sum_processed, buf_len);
1492 			if (processed == -1)
1493 				break;
1494 			buf_len -= processed;
1495 			sum_processed += processed;
1496 		} while (processed != 0 && buf_len > 0);
1497 		if (processed == -1) {
1498 			read_len = -1;
1499 			break;
1500 		}
1501 		memmove(buf, buf + sum_processed, buf_len);
1502 	}
1503 
1504 	fetchIO_close(f);
1505 
1506 	ret = read_len < 0 ? -1 : 0;
1507 
1508 	if (do_cache) {
1509 		if (ret == 0) {
1510 			cache->next = index_cache;
1511 			index_cache = cache;
1512 		}
1513 
1514 		if (fetchAppendURLList(ue, &cache->ue))
1515 			ret = -1;
1516 	}
1517 
1518 	return ret;
1519 }
1520