/******************************************************************************
Copyright 1993, 1998 The Open Group
Permission to use, copy, modify, distribute, and sell this software and its
documentation for any purpose is hereby granted without fee, provided that
the above copyright notice appear in all copies and that both that
copyright notice and this permission notice appear in supporting
documentation.
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
Except as contained in this notice, the name of The Open Group shall not be
used in advertising or otherwise to promote the sale, use or other dealings
in this Software without prior written authorization from The Open Group.
Author: Ralph Mor, X Consortium
******************************************************************************/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <X11/ICE/ICElib.h>
#include "ICElibint.h"
#include <X11/ICE/ICEutil.h>
#include <time.h>
#define Time_t time_t
#ifdef HAVE_LIBBSD
#include <bsd/stdlib.h> /* for arc4random_buf() */
#endif
static int was_called_state;
#ifndef HAVE_ARC4RANDOM_BUF
static void
emulate_getrandom_buf (
char *auth,
int len
)
{
long ldata[2];
int seed;
int value;
int i;
#ifdef ITIMER_REAL
{
struct timeval now;
X_GETTIMEOFDAY (&now);
ldata[0] = now.tv_sec;
ldata[1] = now.tv_usec;
}
#else /* ITIMER_REAL */
{
long time ();
ldata[0] = time ((long *) 0);
ldata[1] = getpid ();
}
#endif /* ITIMER_REAL */
seed = (ldata[0]) + (ldata[1] << 16);
srand (seed);
for (i = 0; i < len; i++)
{
value = rand ();
auth[i] = value & 0xff;
}
}
#ifndef HAVE_GETENTROPY
#include <sys/syscall.h>
#include <errno.h>
/* code taken from libressl, license: */
/*
* Copyright (c) 2014 Theo de Raadt <deraadt@openbsd.org>
* Copyright (c) 2014 Bob Beck <beck@obtuse.com>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* Emulation of getentropy(2) as documented at:
* http://man.openbsd.org/getentropy.2
*/
#ifdef __NR_getrandom
static int
getentropy(void *buf, size_t len)
{
int pre_errno = errno;
int ret;
if (len > 256)
return (-1);
do {
ret = syscall(__NR_getrandom, buf, len, 0);
} while (ret == -1 && errno == EINTR);
if (ret != len)
return (-1);
errno = pre_errno;
fprintf(stderr, "generating cookie with syscall\n");
return (0);
}
#define HAVE_GETENTROPY 1
#endif /* __NR_getrandom */
#endif /* HAVE_GETENTROPY */
static void
arc4random_buf (
char *auth,
int len
)
{
int ret;
#if HAVE_GETENTROPY
/* weak emulation of arc4random through the entropy libc */
ret = getentropy (auth, len);
if (ret == 0)
return;
#endif /* HAVE_GETENTROPY */
emulate_getrandom_buf (auth, len);
}
#endif /* !defined(HAVE_ARC4RANDOM_BUF) */
/*
* MIT-MAGIC-COOKIE-1 is a sample authentication method implemented by
* the SI. It is not part of standard ICElib.
*/
char *
IceGenerateMagicCookie (
int len
)
{
char *auth;
if ((auth = malloc (len + 1)) == NULL)
return (NULL);
arc4random_buf (auth, len);
auth[len] = '\0';
return (auth);
}
IcePoAuthStatus
_IcePoMagicCookie1Proc (
IceConn iceConn,
IcePointer *authStatePtr,
Bool cleanUp,
Bool swap,
int authDataLen,
IcePointer authData,
int *replyDataLenRet,
IcePointer *replyDataRet,
char **errorStringRet
)
{
if (cleanUp)
{
/*
* We didn't allocate any state. We're done.
*/
return (IcePoAuthDoneCleanup);
}
*errorStringRet = NULL;
if (*authStatePtr == NULL)
{
/*
* This is the first time we're being called. Search the
* authentication data for the first occurence of
* MIT-MAGIC-COOKIE-1 that matches iceConn->connection_string.
*/
unsigned short length;
char *data;
_IceGetPoAuthData ("ICE", iceConn->connection_string,
"MIT-MAGIC-COOKIE-1", &length, &data);
if (!data)
{
const char *tempstr =
"Could not find correct MIT-MAGIC-COOKIE-1 authentication";
*errorStringRet = strdup(tempstr);
return (IcePoAuthFailed);
}
else
{
*authStatePtr = (IcePointer) &was_called_state;
*replyDataLenRet = length;
*replyDataRet = data;
return (IcePoAuthHaveReply);
}
}
else
{
/*
* We should never get here for MIT-MAGIC-COOKIE-1 since it is
* a single pass authentication method.
*/
const char *tempstr =
"MIT-MAGIC-COOKIE-1 authentication internal error";
*errorStringRet = strdup(tempstr);
return (IcePoAuthFailed);
}
}
IcePoAuthProc _IcePoAuthProcs[] = {_IcePoMagicCookie1Proc};
IcePaAuthStatus
_IcePaMagicCookie1Proc (
IceConn iceConn,
IcePointer *authStatePtr,
Bool swap,
int authDataLen,
IcePointer authData,
int *replyDataLenRet,
IcePointer *replyDataRet,
char **errorStringRet
)
{
*errorStringRet = NULL;
*replyDataLenRet = 0;
*replyDataRet = NULL;
if (*authStatePtr == NULL)
{
/*
* This is the first time we're being called. We don't have
* any data to pass to the other client.
*/
*authStatePtr = (IcePointer) &was_called_state;
return (IcePaAuthContinue);
}
else
{
/*
* Search the authentication data for the first occurence of
* MIT-MAGIC-COOKIE-1 that matches iceConn->connection_string.
*/
unsigned short length;
char *data;
_IceGetPaAuthData ("ICE", iceConn->connection_string,
"MIT-MAGIC-COOKIE-1", &length, &data);
if (data)
{
IcePaAuthStatus stat;
if (authDataLen == length &&
memcmp (authData, data, authDataLen) == 0)
{
stat = IcePaAuthAccepted;
}
else
{
const char *tempstr
= "MIT-MAGIC-COOKIE-1 authentication rejected";
*errorStringRet = strdup(tempstr);
stat = IcePaAuthRejected;
}
free (data);
return (stat);
}
else
{
/*
* We should never get here because in the ConnectionReply
* we should have passed all the valid methods. So we should
* always find a valid entry.
*/
const char *tempstr =
"MIT-MAGIC-COOKIE-1 authentication internal error";
*errorStringRet = strdup(tempstr);
return (IcePaAuthFailed);
}
}
}
IcePaAuthProc _IcePaAuthProcs[] = {_IcePaMagicCookie1Proc};