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/* $OpenBSD: auth2-none.c,v 1.14 2007/08/23 03:22:16 djm Exp $ */
/*
* Copyright (c) 2000 Markus Friedl. 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.
* 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.
*
* 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/types.h>
#include <sys/stat.h>
#include <sys/uio.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include "xmalloc.h"
#include "key.h"
#include "hostfile.h"
#include "auth.h"
#include "packet.h"
#include "log.h"
#include "buffer.h"
#include "servconf.h"
#include "atomicio.h"
#include "compat.h"
#include "ssh2.h"
#ifdef GSSAPI
#include "ssh-gss.h"
#endif
#include "monitor_wrap.h"
/* import */
extern ServerOptions options;
/* "none" is allowed only one time */
static int none_enabled = 1;
char *
auth2_read_banner(void)
{
struct stat st;
char *banner = NULL;
size_t len, n;
int fd;
if ((fd = open(options.banner, O_RDONLY)) == -1)
return (NULL);
if (fstat(fd, &st) == -1) {
close(fd);
return (NULL);
}
if (st.st_size > 1*1024*1024) {
close(fd);
return (NULL);
}
len = (size_t)st.st_size; /* truncate */
banner = xmalloc(len + 1);
n = atomicio(read, fd, banner, len);
close(fd);
if (n != len) {
xfree(banner);
return (NULL);
}
banner[n] = '\0';
return (banner);
}
static void
userauth_banner(void)
{
char *banner = NULL;
if (options.banner == NULL ||
strcasecmp(options.banner, "none") == 0 ||
(datafellows & SSH_BUG_BANNER) != 0)
return;
if ((banner = PRIVSEP(auth2_read_banner())) == NULL)
goto done;
packet_start(SSH2_MSG_USERAUTH_BANNER);
packet_put_cstring(banner);
packet_put_cstring(""); /* language, unused */
packet_send();
debug("userauth_banner: sent");
done:
if (banner)
xfree(banner);
}
static int
userauth_none(Authctxt *authctxt)
{
none_enabled = 0;
packet_check_eom();
userauth_banner();
if (options.password_authentication)
return (PRIVSEP(auth_password(authctxt, "")));
return (0);
}
Authmethod method_none = {
"none",
userauth_none,
&none_enabled
};
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