FreeBSD-5.3/lib/libfetch/http.c
/*-
* Copyright (c) 2000 Dag-Erling Coïdan Smørgrav
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer
* in this position and unchanged.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/lib/libfetch/http.c,v 1.73 2004/08/07 20:23:50 des Exp $");
/*
* The following copyright applies to the base64 code:
*
*-
* Copyright 1997 Massachusetts Institute of Technology
*
* Permission to use, copy, modify, and distribute this software and
* its documentation for any purpose and without fee is hereby
* granted, provided that both the above copyright notice and this
* permission notice appear in all copies, that both the above
* copyright notice and this permission notice appear in all
* supporting documentation, and that the name of M.I.T. not be used
* in advertising or publicity pertaining to distribution of the
* software without specific, written prior permission. M.I.T. makes
* no representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied
* warranty.
*
* THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS
* ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
* SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/param.h>
#include <sys/socket.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <locale.h>
#include <netdb.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include "fetch.h"
#include "common.h"
#include "httperr.h"
/* Maximum number of redirects to follow */
#define MAX_REDIRECT 5
/* Symbolic names for reply codes we care about */
#define HTTP_OK 200
#define HTTP_PARTIAL 206
#define HTTP_MOVED_PERM 301
#define HTTP_MOVED_TEMP 302
#define HTTP_SEE_OTHER 303
#define HTTP_NEED_AUTH 401
#define HTTP_NEED_PROXY_AUTH 407
#define HTTP_BAD_RANGE 416
#define HTTP_PROTOCOL_ERROR 999
#define HTTP_REDIRECT(xyz) ((xyz) == HTTP_MOVED_PERM \
|| (xyz) == HTTP_MOVED_TEMP \
|| (xyz) == HTTP_SEE_OTHER)
#define HTTP_ERROR(xyz) ((xyz) > 400 && (xyz) < 599)
/*****************************************************************************
* I/O functions for decoding chunked streams
*/
struct httpio
{
conn_t *conn; /* connection */
int chunked; /* chunked mode */
char *buf; /* chunk buffer */
size_t bufsize; /* size of chunk buffer */
ssize_t buflen; /* amount of data currently in buffer */
int bufpos; /* current read offset in buffer */
int eof; /* end-of-file flag */
int error; /* error flag */
size_t chunksize; /* remaining size of current chunk */
#ifndef NDEBUG
size_t total;
#endif
};
/*
* Get next chunk header
*/
static int
_http_new_chunk(struct httpio *io)
{
char *p;
if (_fetch_getln(io->conn) == -1)
return (-1);
if (io->conn->buflen < 2 || !ishexnumber(*io->conn->buf))
return (-1);
for (p = io->conn->buf; *p && !isspace(*p); ++p) {
if (*p == ';')
break;
if (!ishexnumber(*p))
return (-1);
if (isdigit(*p)) {
io->chunksize = io->chunksize * 16 +
*p - '0';
} else {
io->chunksize = io->chunksize * 16 +
10 + tolower(*p) - 'a';
}
}
#ifndef NDEBUG
if (fetchDebug) {
io->total += io->chunksize;
if (io->chunksize == 0)
fprintf(stderr, "%s(): end of last chunk\n", __func__);
else
fprintf(stderr, "%s(): new chunk: %lu (%lu)\n",
__func__, (unsigned long)io->chunksize,
(unsigned long)io->total);
}
#endif
return (io->chunksize);
}
/*
* Grow the input buffer to at least len bytes
*/
static inline int
_http_growbuf(struct httpio *io, size_t len)
{
char *tmp;
if (io->bufsize >= len)
return (0);
if ((tmp = realloc(io->buf, len)) == NULL)
return (-1);
io->buf = tmp;
io->bufsize = len;
return (0);
}
/*
* Fill the input buffer, do chunk decoding on the fly
*/
static int
_http_fillbuf(struct httpio *io, size_t len)
{
if (io->error)
return (-1);
if (io->eof)
return (0);
if (io->chunked == 0) {
if (_http_growbuf(io, len) == -1)
return (-1);
if ((io->buflen = _fetch_read(io->conn, io->buf, len)) == -1) {
io->error = 1;
return (-1);
}
io->bufpos = 0;
return (io->buflen);
}
if (io->chunksize == 0) {
switch (_http_new_chunk(io)) {
case -1:
io->error = 1;
return (-1);
case 0:
io->eof = 1;
return (0);
}
}
if (len > io->chunksize)
len = io->chunksize;
if (_http_growbuf(io, len) == -1)
return (-1);
if ((io->buflen = _fetch_read(io->conn, io->buf, len)) == -1) {
io->error = 1;
return (-1);
}
io->chunksize -= io->buflen;
if (io->chunksize == 0) {
char endl[2];
if (_fetch_read(io->conn, endl, 2) != 2 ||
endl[0] != '\r' || endl[1] != '\n')
return (-1);
}
io->bufpos = 0;
return (io->buflen);
}
/*
* Read function
*/
static int
_http_readfn(void *v, char *buf, int len)
{
struct httpio *io = (struct httpio *)v;
int l, pos;
if (io->error)
return (-1);
if (io->eof)
return (0);
for (pos = 0; len > 0; pos += l, len -= l) {
/* empty buffer */
if (!io->buf || io->bufpos == io->buflen)
if (_http_fillbuf(io, len) < 1)
break;
l = io->buflen - io->bufpos;
if (len < l)
l = len;
bcopy(io->buf + io->bufpos, buf + pos, l);
io->bufpos += l;
}
if (!pos && io->error)
return (-1);
return (pos);
}
/*
* Write function
*/
static int
_http_writefn(void *v, const char *buf, int len)
{
struct httpio *io = (struct httpio *)v;
return (_fetch_write(io->conn, buf, len));
}
/*
* Close function
*/
static int
_http_closefn(void *v)
{
struct httpio *io = (struct httpio *)v;
int r;
r = _fetch_close(io->conn);
if (io->buf)
free(io->buf);
free(io);
return (r);
}
/*
* Wrap a file descriptor up
*/
static FILE *
_http_funopen(conn_t *conn, int chunked)
{
struct httpio *io;
FILE *f;
if ((io = calloc(1, sizeof(*io))) == NULL) {
_fetch_syserr();
return (NULL);
}
io->conn = conn;
io->chunked = chunked;
f = funopen(io, _http_readfn, _http_writefn, NULL, _http_closefn);
if (f == NULL) {
_fetch_syserr();
free(io);
return (NULL);
}
return (f);
}
/*****************************************************************************
* Helper functions for talking to the server and parsing its replies
*/
/* Header types */
typedef enum {
hdr_syserror = -2,
hdr_error = -1,
hdr_end = 0,
hdr_unknown = 1,
hdr_content_length,
hdr_content_range,
hdr_last_modified,
hdr_location,
hdr_transfer_encoding,
hdr_www_authenticate
} hdr_t;
/* Names of interesting headers */
static struct {
hdr_t num;
const char *name;
} hdr_names[] = {
{ hdr_content_length, "Content-Length" },
{ hdr_content_range, "Content-Range" },
{ hdr_last_modified, "Last-Modified" },
{ hdr_location, "Location" },
{ hdr_transfer_encoding, "Transfer-Encoding" },
{ hdr_www_authenticate, "WWW-Authenticate" },
{ hdr_unknown, NULL },
};
/*
* Send a formatted line; optionally echo to terminal
*/
static int
_http_cmd(conn_t *conn, const char *fmt, ...)
{
va_list ap;
size_t len;
char *msg;
int r;
va_start(ap, fmt);
len = vasprintf(&msg, fmt, ap);
va_end(ap);
if (msg == NULL) {
errno = ENOMEM;
_fetch_syserr();
return (-1);
}
r = _fetch_putln(conn, msg, len);
free(msg);
if (r == -1) {
_fetch_syserr();
return (-1);
}
return (0);
}
/*
* Get and parse status line
*/
static int
_http_get_reply(conn_t *conn)
{
char *p;
if (_fetch_getln(conn) == -1)
return (-1);
/*
* A valid status line looks like "HTTP/m.n xyz reason" where m
* and n are the major and minor protocol version numbers and xyz
* is the reply code.
* Unfortunately, there are servers out there (NCSA 1.5.1, to name
* just one) that do not send a version number, so we can't rely
* on finding one, but if we do, insist on it being 1.0 or 1.1.
* We don't care about the reason phrase.
*/
if (strncmp(conn->buf, "HTTP", 4) != 0)
return (HTTP_PROTOCOL_ERROR);
p = conn->buf + 4;
if (*p == '/') {
if (p[1] != '1' || p[2] != '.' || (p[3] != '0' && p[3] != '1'))
return (HTTP_PROTOCOL_ERROR);
p += 4;
}
if (*p != ' ' || !isdigit(p[1]) || !isdigit(p[2]) || !isdigit(p[3]))
return (HTTP_PROTOCOL_ERROR);
conn->err = (p[1] - '0') * 100 + (p[2] - '0') * 10 + (p[3] - '0');
return (conn->err);
}
/*
* Check a header; if the type matches the given string, return a pointer
* to the beginning of the value.
*/
static const char *
_http_match(const char *str, const char *hdr)
{
while (*str && *hdr && tolower(*str++) == tolower(*hdr++))
/* nothing */;
if (*str || *hdr != ':')
return (NULL);
while (*hdr && isspace(*++hdr))
/* nothing */;
return (hdr);
}
/*
* Get the next header and return the appropriate symbolic code.
*/
static hdr_t
_http_next_header(conn_t *conn, const char **p)
{
int i;
if (_fetch_getln(conn) == -1)
return (hdr_syserror);
while (conn->buflen && isspace(conn->buf[conn->buflen - 1]))
conn->buflen--;
conn->buf[conn->buflen] = '\0';
if (conn->buflen == 0)
return (hdr_end);
/*
* We could check for malformed headers but we don't really care.
* A valid header starts with a token immediately followed by a
* colon; a token is any sequence of non-control, non-whitespace
* characters except "()<>@,;:\\\"{}".
*/
for (i = 0; hdr_names[i].num != hdr_unknown; i++)
if ((*p = _http_match(hdr_names[i].name, conn->buf)) != NULL)
return (hdr_names[i].num);
return (hdr_unknown);
}
/*
* Parse a last-modified header
*/
static int
_http_parse_mtime(const char *p, time_t *mtime)
{
char locale[64], *r;
struct tm tm;
strncpy(locale, setlocale(LC_TIME, NULL), sizeof(locale));
setlocale(LC_TIME, "C");
r = strptime(p, "%a, %d %b %Y %H:%M:%S GMT", &tm);
/* XXX should add support for date-2 and date-3 */
setlocale(LC_TIME, locale);
if (r == NULL)
return (-1);
DEBUG(fprintf(stderr, "last modified: [%04d-%02d-%02d "
"%02d:%02d:%02d]\n",
tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday,
tm.tm_hour, tm.tm_min, tm.tm_sec));
*mtime = timegm(&tm);
return (0);
}
/*
* Parse a content-length header
*/
static int
_http_parse_length(const char *p, off_t *length)
{
off_t len;
for (len = 0; *p && isdigit(*p); ++p)
len = len * 10 + (*p - '0');
if (*p)
return (-1);
DEBUG(fprintf(stderr, "content length: [%lld]\n",
(long long)len));
*length = len;
return (0);
}
/*
* Parse a content-range header
*/
static int
_http_parse_range(const char *p, off_t *offset, off_t *length, off_t *size)
{
off_t first, last, len;
if (strncasecmp(p, "bytes ", 6) != 0)
return (-1);
p += 6;
if (*p == '*') {
first = last = -1;
++p;
} else {
for (first = 0; *p && isdigit(*p); ++p)
first = first * 10 + *p - '0';
if (*p != '-')
return (-1);
for (last = 0, ++p; *p && isdigit(*p); ++p)
last = last * 10 + *p - '0';
}
if (first > last || *p != '/')
return (-1);
for (len = 0, ++p; *p && isdigit(*p); ++p)
len = len * 10 + *p - '0';
if (*p || len < last - first + 1)
return (-1);
if (first == -1) {
DEBUG(fprintf(stderr, "content range: [*/%lld]\n",
(long long)len));
*length = 0;
} else {
DEBUG(fprintf(stderr, "content range: [%lld-%lld/%lld]\n",
(long long)first, (long long)last, (long long)len));
*length = last - first + 1;
}
*offset = first;
*size = len;
return (0);
}
/*****************************************************************************
* Helper functions for authorization
*/
/*
* Base64 encoding
*/
static char *
_http_base64(const char *src)
{
static const char base64[] =
"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
"abcdefghijklmnopqrstuvwxyz"
"0123456789+/";
char *str, *dst;
size_t l;
int t, r;
l = strlen(src);
if ((str = malloc(((l + 2) / 3) * 4 + 1)) == NULL)
return (NULL);
dst = str;
r = 0;
while (l >= 3) {
t = (src[0] << 16) | (src[1] << 8) | src[2];
dst[0] = base64[(t >> 18) & 0x3f];
dst[1] = base64[(t >> 12) & 0x3f];
dst[2] = base64[(t >> 6) & 0x3f];
dst[3] = base64[(t >> 0) & 0x3f];
src += 3; l -= 3;
dst += 4; r += 4;
}
switch (l) {
case 2:
t = (src[0] << 16) | (src[1] << 8);
dst[0] = base64[(t >> 18) & 0x3f];
dst[1] = base64[(t >> 12) & 0x3f];
dst[2] = base64[(t >> 6) & 0x3f];
dst[3] = '=';
dst += 4;
r += 4;
break;
case 1:
t = src[0] << 16;
dst[0] = base64[(t >> 18) & 0x3f];
dst[1] = base64[(t >> 12) & 0x3f];
dst[2] = dst[3] = '=';
dst += 4;
r += 4;
break;
case 0:
break;
}
*dst = 0;
return (str);
}
/*
* Encode username and password
*/
static int
_http_basic_auth(conn_t *conn, const char *hdr, const char *usr, const char *pwd)
{
char *upw, *auth;
int r;
DEBUG(fprintf(stderr, "usr: [%s]\n", usr));
DEBUG(fprintf(stderr, "pwd: [%s]\n", pwd));
if (asprintf(&upw, "%s:%s", usr, pwd) == -1)
return (-1);
auth = _http_base64(upw);
free(upw);
if (auth == NULL)
return (-1);
r = _http_cmd(conn, "%s: Basic %s", hdr, auth);
free(auth);
return (r);
}
/*
* Send an authorization header
*/
static int
_http_authorize(conn_t *conn, const char *hdr, const char *p)
{
/* basic authorization */
if (strncasecmp(p, "basic:", 6) == 0) {
char *user, *pwd, *str;
int r;
/* skip realm */
for (p += 6; *p && *p != ':'; ++p)
/* nothing */ ;
if (!*p || strchr(++p, ':') == NULL)
return (-1);
if ((str = strdup(p)) == NULL)
return (-1); /* XXX */
user = str;
pwd = strchr(str, ':');
*pwd++ = '\0';
r = _http_basic_auth(conn, hdr, user, pwd);
free(str);
return (r);
}
return (-1);
}
/*****************************************************************************
* Helper functions for connecting to a server or proxy
*/
/*
* Connect to the correct HTTP server or proxy.
*/
static conn_t *
_http_connect(struct url *URL, struct url *purl, const char *flags)
{
conn_t *conn;
int verbose;
int af;
#ifdef INET6
af = AF_UNSPEC;
#else
af = AF_INET;
#endif
verbose = CHECK_FLAG('v');
if (CHECK_FLAG('4'))
af = AF_INET;
#ifdef INET6
else if (CHECK_FLAG('6'))
af = AF_INET6;
#endif
if (purl && strcasecmp(URL->scheme, SCHEME_HTTPS) != 0) {
URL = purl;
} else if (strcasecmp(URL->scheme, SCHEME_FTP) == 0) {
/* can't talk http to an ftp server */
/* XXX should set an error code */
return (NULL);
}
if ((conn = _fetch_connect(URL->host, URL->port, af, verbose)) == NULL)
/* _fetch_connect() has already set an error code */
return (NULL);
if (strcasecmp(URL->scheme, SCHEME_HTTPS) == 0 &&
_fetch_ssl(conn, verbose) == -1) {
_fetch_close(conn);
/* grrr */
errno = EAUTH;
_fetch_syserr();
return (NULL);
}
return (conn);
}
static struct url *
_http_get_proxy(const char *flags)
{
struct url *purl;
char *p;
if (flags != NULL && strchr(flags, 'd') != NULL)
return (NULL);
if (((p = getenv("HTTP_PROXY")) || (p = getenv("http_proxy"))) &&
(purl = fetchParseURL(p))) {
if (!*purl->scheme)
strcpy(purl->scheme, SCHEME_HTTP);
if (!purl->port)
purl->port = _fetch_default_proxy_port(purl->scheme);
if (strcasecmp(purl->scheme, SCHEME_HTTP) == 0)
return (purl);
fetchFreeURL(purl);
}
return (NULL);
}
static void
_http_print_html(FILE *out, FILE *in)
{
size_t len;
char *line, *p, *q;
int comment, tag;
comment = tag = 0;
while ((line = fgetln(in, &len)) != NULL) {
while (len && isspace(line[len - 1]))
--len;
for (p = q = line; q < line + len; ++q) {
if (comment && *q == '-') {
if (q + 2 < line + len &&
strcmp(q, "-->") == 0) {
tag = comment = 0;
q += 2;
}
} else if (tag && !comment && *q == '>') {
p = q + 1;
tag = 0;
} else if (!tag && *q == '<') {
if (q > p)
fwrite(p, q - p, 1, out);
tag = 1;
if (q + 3 < line + len &&
strcmp(q, "<!--") == 0) {
comment = 1;
q += 3;
}
}
}
if (!tag && q > p)
fwrite(p, q - p, 1, out);
fputc('\n', out);
}
}
/*****************************************************************************
* Core
*/
/*
* Send a request and process the reply
*
* XXX This function is way too long, the do..while loop should be split
* XXX off into a separate function.
*/
FILE *
_http_request(struct url *URL, const char *op, struct url_stat *us,
struct url *purl, const char *flags)
{
conn_t *conn;
struct url *url, *new;
int chunked, direct, need_auth, noredirect, verbose;
int e, i, n;
off_t offset, clength, length, size;
time_t mtime;
const char *p;
FILE *f;
hdr_t h;
char hbuf[MAXHOSTNAMELEN + 7], *host;
direct = CHECK_FLAG('d');
noredirect = CHECK_FLAG('A');
verbose = CHECK_FLAG('v');
if (direct && purl) {
fetchFreeURL(purl);
purl = NULL;
}
/* try the provided URL first */
url = URL;
/* if the A flag is set, we only get one try */
n = noredirect ? 1 : MAX_REDIRECT;
i = 0;
e = HTTP_PROTOCOL_ERROR;
need_auth = 0;
do {
new = NULL;
chunked = 0;
offset = 0;
clength = -1;
length = -1;
size = -1;
mtime = 0;
/* check port */
if (!url->port)
url->port = _fetch_default_port(url->scheme);
/* were we redirected to an FTP URL? */
if (purl == NULL && strcmp(url->scheme, SCHEME_FTP) == 0) {
if (strcmp(op, "GET") == 0)
return (_ftp_request(url, "RETR", us, purl, flags));
else if (strcmp(op, "HEAD") == 0)
return (_ftp_request(url, "STAT", us, purl, flags));
}
/* connect to server or proxy */
if ((conn = _http_connect(url, purl, flags)) == NULL)
goto ouch;
host = url->host;
#ifdef INET6
if (strchr(url->host, ':')) {
snprintf(hbuf, sizeof(hbuf), "[%s]", url->host);
host = hbuf;
}
#endif
if (url->port != _fetch_default_port(url->scheme)) {
if (host != hbuf) {
strcpy(hbuf, host);
host = hbuf;
}
snprintf(hbuf + strlen(hbuf),
sizeof(hbuf) - strlen(hbuf), ":%d", url->port);
}
/* send request */
if (verbose)
_fetch_info("requesting %s://%s%s",
url->scheme, host, url->doc);
if (purl) {
_http_cmd(conn, "%s %s://%s%s HTTP/1.1",
op, url->scheme, host, url->doc);
} else {
_http_cmd(conn, "%s %s HTTP/1.1",
op, url->doc);
}
/* virtual host */
_http_cmd(conn, "Host: %s", host);
/* proxy authorization */
if (purl) {
if (*purl->user || *purl->pwd)
_http_basic_auth(conn, "Proxy-Authorization",
purl->user, purl->pwd);
else if ((p = getenv("HTTP_PROXY_AUTH")) != NULL && *p != '\0')
_http_authorize(conn, "Proxy-Authorization", p);
}
/* server authorization */
if (need_auth || *url->user || *url->pwd) {
if (*url->user || *url->pwd)
_http_basic_auth(conn, "Authorization", url->user, url->pwd);
else if ((p = getenv("HTTP_AUTH")) != NULL && *p != '\0')
_http_authorize(conn, "Authorization", p);
else if (fetchAuthMethod && fetchAuthMethod(url) == 0) {
_http_basic_auth(conn, "Authorization", url->user, url->pwd);
} else {
_http_seterr(HTTP_NEED_AUTH);
goto ouch;
}
}
/* other headers */
if ((p = getenv("HTTP_REFERER")) != NULL && *p != '\0') {
if (strcasecmp(p, "auto") == 0)
_http_cmd(conn, "Referer: %s://%s%s",
url->scheme, host, url->doc);
else
_http_cmd(conn, "Referer: %s", p);
}
if ((p = getenv("HTTP_USER_AGENT")) != NULL && *p != '\0')
_http_cmd(conn, "User-Agent: %s", p);
else
_http_cmd(conn, "User-Agent: %s " _LIBFETCH_VER, getprogname());
if (url->offset > 0)
_http_cmd(conn, "Range: bytes=%lld-", (long long)url->offset);
_http_cmd(conn, "Connection: close");
_http_cmd(conn, "");
/* get reply */
switch (_http_get_reply(conn)) {
case HTTP_OK:
case HTTP_PARTIAL:
/* fine */
break;
case HTTP_MOVED_PERM:
case HTTP_MOVED_TEMP:
case HTTP_SEE_OTHER:
/*
* Not so fine, but we still have to read the
* headers to get the new location.
*/
break;
case HTTP_NEED_AUTH:
if (need_auth) {
/*
* We already sent out authorization code,
* so there's nothing more we can do.
*/
_http_seterr(conn->err);
goto ouch;
}
/* try again, but send the password this time */
if (verbose)
_fetch_info("server requires authorization");
break;
case HTTP_NEED_PROXY_AUTH:
/*
* If we're talking to a proxy, we already sent
* our proxy authorization code, so there's
* nothing more we can do.
*/
_http_seterr(conn->err);
goto ouch;
case HTTP_BAD_RANGE:
/*
* This can happen if we ask for 0 bytes because
* we already have the whole file. Consider this
* a success for now, and check sizes later.
*/
break;
case HTTP_PROTOCOL_ERROR:
/* fall through */
case -1:
_fetch_syserr();
goto ouch;
default:
_http_seterr(conn->err);
if (!verbose)
goto ouch;
/* fall through so we can get the full error message */
}
/* get headers */
do {
switch ((h = _http_next_header(conn, &p))) {
case hdr_syserror:
_fetch_syserr();
goto ouch;
case hdr_error:
_http_seterr(HTTP_PROTOCOL_ERROR);
goto ouch;
case hdr_content_length:
_http_parse_length(p, &clength);
break;
case hdr_content_range:
_http_parse_range(p, &offset, &length, &size);
break;
case hdr_last_modified:
_http_parse_mtime(p, &mtime);
break;
case hdr_location:
if (!HTTP_REDIRECT(conn->err))
break;
if (new)
free(new);
if (verbose)
_fetch_info("%d redirect to %s", conn->err, p);
if (*p == '/')
/* absolute path */
new = fetchMakeURL(url->scheme, url->host, url->port, p,
url->user, url->pwd);
else
new = fetchParseURL(p);
if (new == NULL) {
/* XXX should set an error code */
DEBUG(fprintf(stderr, "failed to parse new URL\n"));
goto ouch;
}
if (!*new->user && !*new->pwd) {
strcpy(new->user, url->user);
strcpy(new->pwd, url->pwd);
}
new->offset = url->offset;
new->length = url->length;
break;
case hdr_transfer_encoding:
/* XXX weak test*/
chunked = (strcasecmp(p, "chunked") == 0);
break;
case hdr_www_authenticate:
if (conn->err != HTTP_NEED_AUTH)
break;
/* if we were smarter, we'd check the method and realm */
break;
case hdr_end:
/* fall through */
case hdr_unknown:
/* ignore */
break;
}
} while (h > hdr_end);
/* we need to provide authentication */
if (conn->err == HTTP_NEED_AUTH) {
e = conn->err;
need_auth = 1;
_fetch_close(conn);
conn = NULL;
continue;
}
/* requested range not satisfiable */
if (conn->err == HTTP_BAD_RANGE) {
if (url->offset == size && url->length == 0) {
/* asked for 0 bytes; fake it */
offset = url->offset;
conn->err = HTTP_OK;
break;
} else {
_http_seterr(conn->err);
goto ouch;
}
}
/* we have a hit or an error */
if (conn->err == HTTP_OK || conn->err == HTTP_PARTIAL || HTTP_ERROR(conn->err))
break;
/* all other cases: we got a redirect */
e = conn->err;
need_auth = 0;
_fetch_close(conn);
conn = NULL;
if (!new) {
DEBUG(fprintf(stderr, "redirect with no new location\n"));
break;
}
if (url != URL)
fetchFreeURL(url);
url = new;
} while (++i < n);
/* we failed, or ran out of retries */
if (conn == NULL) {
_http_seterr(e);
goto ouch;
}
DEBUG(fprintf(stderr, "offset %lld, length %lld,"
" size %lld, clength %lld\n",
(long long)offset, (long long)length,
(long long)size, (long long)clength));
/* check for inconsistencies */
if (clength != -1 && length != -1 && clength != length) {
_http_seterr(HTTP_PROTOCOL_ERROR);
goto ouch;
}
if (clength == -1)
clength = length;
if (clength != -1)
length = offset + clength;
if (length != -1 && size != -1 && length != size) {
_http_seterr(HTTP_PROTOCOL_ERROR);
goto ouch;
}
if (size == -1)
size = length;
/* fill in stats */
if (us) {
us->size = size;
us->atime = us->mtime = mtime;
}
/* too far? */
if (URL->offset > 0 && offset > URL->offset) {
_http_seterr(HTTP_PROTOCOL_ERROR);
goto ouch;
}
/* report back real offset and size */
URL->offset = offset;
URL->length = clength;
/* wrap it up in a FILE */
if ((f = _http_funopen(conn, chunked)) == NULL) {
_fetch_syserr();
goto ouch;
}
if (url != URL)
fetchFreeURL(url);
if (purl)
fetchFreeURL(purl);
if (HTTP_ERROR(conn->err)) {
_http_print_html(stderr, f);
fclose(f);
f = NULL;
}
return (f);
ouch:
if (url != URL)
fetchFreeURL(url);
if (purl)
fetchFreeURL(purl);
if (conn != NULL)
_fetch_close(conn);
return (NULL);
}
/*****************************************************************************
* Entry points
*/
/*
* Retrieve and stat a file by HTTP
*/
FILE *
fetchXGetHTTP(struct url *URL, struct url_stat *us, const char *flags)
{
return (_http_request(URL, "GET", us, _http_get_proxy(flags), flags));
}
/*
* Retrieve a file by HTTP
*/
FILE *
fetchGetHTTP(struct url *URL, const char *flags)
{
return (fetchXGetHTTP(URL, NULL, flags));
}
/*
* Store a file by HTTP
*/
FILE *
fetchPutHTTP(struct url *URL __unused, const char *flags __unused)
{
warnx("fetchPutHTTP(): not implemented");
return (NULL);
}
/*
* Get an HTTP document's metadata
*/
int
fetchStatHTTP(struct url *URL, struct url_stat *us, const char *flags)
{
FILE *f;
f = _http_request(URL, "HEAD", us, _http_get_proxy(flags), flags);
if (f == NULL)
return (-1);
fclose(f);
return (0);
}
/*
* List a directory
*/
struct url_ent *
fetchListHTTP(struct url *url __unused, const char *flags __unused)
{
warnx("fetchListHTTP(): not implemented");
return (NULL);
}