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http.c
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http.c
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/*-
* Copyright (c) 2000-2014 Dag-Erling 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: stable/10/lib/libfetch/http.c 262560 2014-02-27 13:27:04Z des $");
/*
* 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 <sys/time.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>
#ifdef WITH_SSL
#include <openssl/md5.h>
#define MD5Init(c) MD5_Init(c)
#define MD5Update(c, data, len) MD5_Update(c, data, len)
#define MD5Final(md, c) MD5_Final(md, c)
#else
#include <md5.h>
#endif
#include <netinet/in.h>
#include <netinet/tcp.h>
#include "fetch.h"
#include "common.h"
#include "httperr.h"
/* Maximum number of redirects to follow */
#define MAX_REDIRECT 20
/* 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_NOT_MODIFIED 304
#define HTTP_USE_PROXY 305
#define HTTP_TEMP_REDIRECT 307
#define HTTP_PERM_REDIRECT 308
#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_TEMP_REDIRECT \
|| (xyz) == HTTP_USE_PROXY \
|| (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 || !isxdigit((unsigned char)*io->conn->buf))
return (-1);
for (p = io->conn->buf; *p && !isspace((unsigned char)*p); ++p) {
if (*p == ';')
break;
if (!isxdigit((unsigned char)*p))
return (-1);
if (isdigit((unsigned char)*p)) {
io->chunksize = io->chunksize * 16 +
*p - '0';
} else {
io->chunksize = io->chunksize * 16 +
10 + tolower((unsigned char)*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 ssize_t
http_fillbuf(struct httpio *io, size_t len)
{
ssize_t nbytes;
char ch;
if (io->error)
return (-1);
if (io->eof)
return (0);
if (io->chunked == 0) {
if (http_growbuf(io, len) == -1)
return (-1);
if ((nbytes = fetch_read(io->conn, io->buf, len)) == -1) {
io->error = errno;
return (-1);
}
io->buflen = nbytes;
io->bufpos = 0;
return (io->buflen);
}
if (io->chunksize == 0) {
switch (http_new_chunk(io)) {
case -1:
io->error = EPROTO;
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 ((nbytes = fetch_read(io->conn, io->buf, len)) == -1) {
io->error = errno;
return (-1);
}
io->buflen = nbytes;
io->chunksize -= io->buflen;
if (io->chunksize == 0) {
if (fetch_read(io->conn, &ch, 1) != 1 || ch != '\r' ||
fetch_read(io->conn, &ch, 1) != 1 || ch != '\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 rlen;
if (io->error)
return (-1);
if (io->eof)
return (0);
/* empty buffer */
if (!io->buf || io->bufpos == io->buflen) {
if ((rlen = http_fillbuf(io, len)) < 0) {
if ((errno = io->error) == EINTR)
io->error = 0;
return (-1);
} else if (rlen == 0) {
return (0);
}
}
rlen = io->buflen - io->bufpos;
if (len < rlen)
rlen = len;
memcpy(buf, io->buf + io->bufpos, rlen);
io->bufpos += rlen;
return (rlen);
}
/*
* 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_proxy_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_proxy_authenticate, "Proxy-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((unsigned char)p[1]) ||
!isdigit((unsigned char)p[2]) ||
!isdigit((unsigned char)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((unsigned char)*str++) == tolower((unsigned char)*hdr++))
/* nothing */;
if (*str || *hdr != ':')
return (NULL);
while (*hdr && isspace((unsigned char)*++hdr))
/* nothing */;
return (hdr);
}
/*
* Get the next header and return the appropriate symbolic code. We
* need to read one line ahead for checking for a continuation line
* belonging to the current header (continuation lines start with
* white space).
*
* We get called with a fresh line already in the conn buffer, either
* from the previous http_next_header() invocation, or, the first
* time, from a fetch_getln() performed by our caller.
*
* This stops when we encounter an empty line (we dont read beyond the header
* area).
*
* Note that the "headerbuf" is just a place to return the result. Its
* contents are not used for the next call. This means that no cleanup
* is needed when ie doing another connection, just call the cleanup when
* fully done to deallocate memory.
*/
/* Limit the max number of continuation lines to some reasonable value */
#define HTTP_MAX_CONT_LINES 10
/* Place into which to build a header from one or several lines */
typedef struct {
char *buf; /* buffer */
size_t bufsize; /* buffer size */
size_t buflen; /* length of buffer contents */
} http_headerbuf_t;
static void
init_http_headerbuf(http_headerbuf_t *buf)
{
buf->buf = NULL;
buf->bufsize = 0;
buf->buflen = 0;
}
static void
clean_http_headerbuf(http_headerbuf_t *buf)
{
if (buf->buf)
free(buf->buf);
init_http_headerbuf(buf);
}
/* Remove whitespace at the end of the buffer */
static void
http_conn_trimright(conn_t *conn)
{
while (conn->buflen &&
isspace((unsigned char)conn->buf[conn->buflen - 1]))
conn->buflen--;
conn->buf[conn->buflen] = '\0';
}
static hdr_t
http_next_header(conn_t *conn, http_headerbuf_t *hbuf, const char **p)
{
unsigned int i, len;
/*
* Have to do the stripping here because of the first line. So
* it's done twice for the subsequent lines. No big deal
*/
http_conn_trimright(conn);
if (conn->buflen == 0)
return (hdr_end);
/* Copy the line to the headerbuf */
if (hbuf->bufsize < conn->buflen + 1) {
if ((hbuf->buf = realloc(hbuf->buf, conn->buflen + 1)) == NULL)
return (hdr_syserror);
hbuf->bufsize = conn->buflen + 1;
}
strcpy(hbuf->buf, conn->buf);
hbuf->buflen = conn->buflen;
/*
* Fetch possible continuation lines. Stop at 1st non-continuation
* and leave it in the conn buffer
*/
for (i = 0; i < HTTP_MAX_CONT_LINES; i++) {
if (fetch_getln(conn) == -1)
return (hdr_syserror);
/*
* Note: we carry on the idea from the previous version
* that a pure whitespace line is equivalent to an empty
* one (so it's not continuation and will be handled when
* we are called next)
*/
http_conn_trimright(conn);
if (conn->buf[0] != ' ' && conn->buf[0] != "\t"[0])
break;
/* Got a continuation line. Concatenate to previous */
len = hbuf->buflen + conn->buflen;
if (hbuf->bufsize < len + 1) {
len *= 2;
if ((hbuf->buf = realloc(hbuf->buf, len + 1)) == NULL)
return (hdr_syserror);
hbuf->bufsize = len + 1;
}
strcpy(hbuf->buf + hbuf->buflen, conn->buf);
hbuf->buflen += conn->buflen;
}
/*
* 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, hbuf->buf)) != NULL)
return (hdr_names[i].num);
return (hdr_unknown);
}
/**************************
* [Proxy-]Authenticate header parsing
*/
/*
* Read doublequote-delimited string into output buffer obuf (allocated
* by caller, whose responsibility it is to ensure that it's big enough)
* cp points to the first char after the initial '"'
* Handles \ quoting
* Returns pointer to the first char after the terminating double quote, or
* NULL for error.
*/
static const char *
http_parse_headerstring(const char *cp, char *obuf)
{
for (;;) {
switch (*cp) {
case 0: /* Unterminated string */
*obuf = 0;
return (NULL);
case '"': /* Ending quote */
*obuf = 0;
return (++cp);
case '\\':
if (*++cp == 0) {
*obuf = 0;
return (NULL);
}
/* FALLTHROUGH */
default:
*obuf++ = *cp++;
}
}
}
/* Http auth challenge schemes */
typedef enum {HTTPAS_UNKNOWN, HTTPAS_BASIC,HTTPAS_DIGEST} http_auth_schemes_t;
/* Data holder for a Basic or Digest challenge. */
typedef struct {
http_auth_schemes_t scheme;
char *realm;
char *qop;
char *nonce;
char *opaque;
char *algo;
int stale;
int nc; /* Nonce count */
} http_auth_challenge_t;
static void
init_http_auth_challenge(http_auth_challenge_t *b)
{
b->scheme = HTTPAS_UNKNOWN;
b->realm = b->qop = b->nonce = b->opaque = b->algo = NULL;
b->stale = b->nc = 0;
}
static void
clean_http_auth_challenge(http_auth_challenge_t *b)
{
if (b->realm)
free(b->realm);
if (b->qop)
free(b->qop);
if (b->nonce)
free(b->nonce);
if (b->opaque)
free(b->opaque);
if (b->algo)
free(b->algo);
init_http_auth_challenge(b);
}
/* Data holder for an array of challenges offered in an http response. */
#define MAX_CHALLENGES 10
typedef struct {
http_auth_challenge_t *challenges[MAX_CHALLENGES];
int count; /* Number of parsed challenges in the array */
int valid; /* We did parse an authenticate header */
} http_auth_challenges_t;
static void
init_http_auth_challenges(http_auth_challenges_t *cs)
{
int i;
for (i = 0; i < MAX_CHALLENGES; i++)
cs->challenges[i] = NULL;
cs->count = cs->valid = 0;
}
static void
clean_http_auth_challenges(http_auth_challenges_t *cs)
{
int i;
/* We rely on non-zero pointers being allocated, not on the count */
for (i = 0; i < MAX_CHALLENGES; i++) {
if (cs->challenges[i] != NULL) {
clean_http_auth_challenge(cs->challenges[i]);
free(cs->challenges[i]);
}
}
init_http_auth_challenges(cs);
}
/*
* Enumeration for lexical elements. Separators will be returned as their own
* ascii value
*/
typedef enum {HTTPHL_WORD=256, HTTPHL_STRING=257, HTTPHL_END=258,
HTTPHL_ERROR = 259} http_header_lex_t;
/*
* Determine what kind of token comes next and return possible value
* in buf, which is supposed to have been allocated big enough by
* caller. Advance input pointer and return element type.
*/
static int
http_header_lex(const char **cpp, char *buf)
{
size_t l;
/* Eat initial whitespace */
*cpp += strspn(*cpp, " \t");
if (**cpp == 0)
return (HTTPHL_END);
/* Separator ? */
if (**cpp == ',' || **cpp == '=')
return (*((*cpp)++));
/* String ? */
if (**cpp == '"') {
*cpp = http_parse_headerstring(++*cpp, buf);
if (*cpp == NULL)
return (HTTPHL_ERROR);
return (HTTPHL_STRING);
}
/* Read other token, until separator or whitespace */
l = strcspn(*cpp, " \t,=");
memcpy(buf, *cpp, l);
buf[l] = 0;
*cpp += l;
return (HTTPHL_WORD);
}
/*
* Read challenges from http xxx-authenticate header and accumulate them
* in the challenges list structure.
*
* Headers with multiple challenges are specified by rfc2617, but
* servers (ie: squid) often send them in separate headers instead,
* which in turn is forbidden by the http spec (multiple headers with
* the same name are only allowed for pure comma-separated lists, see
* rfc2616 sec 4.2).
*
* We support both approaches anyway
*/
static int
http_parse_authenticate(const char *cp, http_auth_challenges_t *cs)
{
int ret = -1;
http_header_lex_t lex;
char *key = malloc(strlen(cp) + 1);
char *value = malloc(strlen(cp) + 1);
char *buf = malloc(strlen(cp) + 1);
if (key == NULL || value == NULL || buf == NULL) {
fetch_syserr();
goto out;
}
/* In any case we've seen the header and we set the valid bit */
cs->valid = 1;
/* Need word first */
lex = http_header_lex(&cp, key);
if (lex != HTTPHL_WORD)
goto out;
/* Loop on challenges */
for (; cs->count < MAX_CHALLENGES; cs->count++) {
cs->challenges[cs->count] =
malloc(sizeof(http_auth_challenge_t));
if (cs->challenges[cs->count] == NULL) {
fetch_syserr();
goto out;
}
init_http_auth_challenge(cs->challenges[cs->count]);
if (!strcasecmp(key, "basic")) {
cs->challenges[cs->count]->scheme = HTTPAS_BASIC;
} else if (!strcasecmp(key, "digest")) {
cs->challenges[cs->count]->scheme = HTTPAS_DIGEST;
} else {
cs->challenges[cs->count]->scheme = HTTPAS_UNKNOWN;
/*
* Continue parsing as basic or digest may
* follow, and the syntax is the same for
* all. We'll just ignore this one when
* looking at the list
*/
}
/* Loop on attributes */
for (;;) {
/* Key */
lex = http_header_lex(&cp, key);
if (lex != HTTPHL_WORD)
goto out;
/* Equal sign */
lex = http_header_lex(&cp, buf);
if (lex != '=')
goto out;
/* Value */
lex = http_header_lex(&cp, value);
if (lex != HTTPHL_WORD && lex != HTTPHL_STRING)
goto out;
if (!strcasecmp(key, "realm"))
cs->challenges[cs->count]->realm =
strdup(value);
else if (!strcasecmp(key, "qop"))
cs->challenges[cs->count]->qop =
strdup(value);
else if (!strcasecmp(key, "nonce"))
cs->challenges[cs->count]->nonce =
strdup(value);
else if (!strcasecmp(key, "opaque"))
cs->challenges[cs->count]->opaque =
strdup(value);
else if (!strcasecmp(key, "algorithm"))
cs->challenges[cs->count]->algo =
strdup(value);
else if (!strcasecmp(key, "stale"))
cs->challenges[cs->count]->stale =
strcasecmp(value, "no");
/* Else ignore unknown attributes */
/* Comma or Next challenge or End */
lex = http_header_lex(&cp, key);
/*
* If we get a word here, this is the beginning of the
* next challenge. Break the attributes loop
*/
if (lex == HTTPHL_WORD)
break;
if (lex == HTTPHL_END) {
/* End while looking for ',' is normal exit */
cs->count++;
ret = 0;
goto out;
}
/* Anything else is an error */
if (lex != ',')
goto out;
} /* End attributes loop */
} /* End challenge loop */
/*
* Challenges max count exceeded. This really can't happen
* with normal data, something's fishy -> error
*/
out:
if (key)
free(key);
if (value)
free(value);
if (buf)
free(buf);
return (ret);
}
/*
* 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((unsigned char)*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((unsigned char)*p); ++p)
first = first * 10 + *p - '0';
if (*p != '-')
return (-1);
for (last = 0, ++p; *p && isdigit((unsigned char)*p); ++p)
last = last * 10 + *p - '0';
}
if (first > last || *p != '/')
return (-1);
for (len = 0, ++p; *p && isdigit((unsigned char)*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] = '=';