glibc/sunrpc/auth_des.c
2017-08-31 15:59:02 +02:00

466 lines
13 KiB
C

/*
* Copyright (c) 2010, Oracle America, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of the "Oracle America, Inc." nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "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
* COPYRIGHT HOLDER OR CONTRIBUTORS 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.
*/
/*
* auth_des.c, client-side implementation of DES authentication
*/
#include <string.h>
#include <stdint.h>
#include <rpc/des_crypt.h>
#include <rpc/types.h>
#include <rpc/auth.h>
#include <rpc/auth_des.h>
#include <rpc/xdr.h>
#include <netinet/in.h> /* XXX: just to get htonl() and ntohl() */
#include <sys/socket.h>
#include <shlib-compat.h>
#define MILLION 1000000L
#define RTIME_TIMEOUT 5 /* seconds to wait for sync */
#define AUTH_PRIVATE(auth) (struct ad_private *) auth->ah_private
#define ALLOC(object_type) (object_type *) mem_alloc(sizeof(object_type))
#define FREE(ptr, size) mem_free((char *)(ptr), (int) size)
#define ATTEMPT(xdr_op) if (!(xdr_op)) return (FALSE)
#define debug(msg) /* printf("%s\n", msg) */
/*
* DES authenticator operations vector
*/
static void authdes_nextverf (AUTH *);
static bool_t authdes_marshal (AUTH *, XDR *);
static bool_t authdes_validate (AUTH *, struct opaque_auth *);
static bool_t authdes_refresh (AUTH *);
static void authdes_destroy (AUTH *);
static bool_t synchronize (struct sockaddr *, struct rpc_timeval *);
static const struct auth_ops authdes_ops = {
authdes_nextverf,
authdes_marshal,
authdes_validate,
authdes_refresh,
authdes_destroy
};
/*
* This struct is pointed to by the ah_private field of an "AUTH *"
*/
struct ad_private {
char *ad_fullname; /* client's full name */
u_int ad_fullnamelen; /* length of name, rounded up */
char *ad_servername; /* server's full name */
u_int ad_servernamelen; /* length of name, rounded up */
uint32_t ad_window; /* client specified window */
bool_t ad_dosync; /* synchronize? */
struct sockaddr ad_syncaddr; /* remote host to synch with */
struct rpc_timeval ad_timediff; /* server's time - client's time */
uint32_t ad_nickname; /* server's nickname for client */
struct authdes_cred ad_cred; /* storage for credential */
struct authdes_verf ad_verf; /* storage for verifier */
struct rpc_timeval ad_timestamp; /* timestamp sent */
des_block ad_xkey; /* encrypted conversation key */
u_char ad_pkey[1024]; /* Servers actual public key */
};
/*
* Create the client des authentication object
*/
AUTH *
authdes_create (const char *servername, u_int window,
struct sockaddr *syncaddr, des_block *ckey)
/* servername - network name of server */
/* window - time to live */
/* syncaddr - optional addr of host to sync with */
/* ckey - optional conversation key to use */
{
char pkey_data[1024];
netobj pkey;
if (!getpublickey (servername, pkey_data))
return NULL;
pkey.n_bytes = pkey_data;
pkey.n_len = strlen (pkey_data) + 1;
return authdes_pk_create (servername, &pkey, window, syncaddr, ckey);
}
#ifdef EXPORT_RPC_SYMBOLS
libc_hidden_def (authdes_create)
#else
libc_hidden_nolink_sunrpc (authdes_create, GLIBC_2_1)
#endif
AUTH *
authdes_pk_create (const char *servername, netobj *pkey, u_int window,
struct sockaddr *syncaddr, des_block *ckey)
{
AUTH *auth;
struct ad_private *ad;
char namebuf[MAXNETNAMELEN + 1];
/*
* Allocate everything now
*/
auth = ALLOC (AUTH);
ad = ALLOC (struct ad_private);
if (auth == NULL || ad == NULL)
{
debug ("authdes_create: out of memory");
goto failed;
}
memset (ad, 0, sizeof (struct ad_private));
memcpy (ad->ad_pkey, pkey->n_bytes, pkey->n_len);
if (!getnetname (namebuf))
goto failed;
ad->ad_fullnamelen = RNDUP (strlen (namebuf));
ad->ad_fullname = mem_alloc (ad->ad_fullnamelen + 1);
ad->ad_servernamelen = strlen (servername);
ad->ad_servername = mem_alloc (ad->ad_servernamelen + 1);
if (ad->ad_fullname == NULL || ad->ad_servername == NULL)
{
debug ("authdes_create: out of memory");
goto failed;
}
/*
* Set up private data
*/
memcpy (ad->ad_fullname, namebuf, ad->ad_fullnamelen + 1);
memcpy (ad->ad_servername, servername, ad->ad_servernamelen + 1);
ad->ad_timediff.tv_sec = ad->ad_timediff.tv_usec = 0;
if (syncaddr != NULL)
{
ad->ad_syncaddr = *syncaddr;
ad->ad_dosync = TRUE;
}
else
ad->ad_dosync = FALSE;
ad->ad_window = window;
if (ckey == NULL)
{
if (key_gendes (&auth->ah_key) < 0)
{
debug ("authdes_create: unable to gen conversation key");
goto failed;
}
}
else
auth->ah_key = *ckey;
/*
* Set up auth handle
*/
auth->ah_cred.oa_flavor = AUTH_DES;
auth->ah_verf.oa_flavor = AUTH_DES;
auth->ah_ops = (struct auth_ops *) &authdes_ops;
auth->ah_private = (caddr_t) ad;
if (!authdes_refresh (auth))
goto failed;
return auth;
failed:
if (auth != NULL)
FREE (auth, sizeof (AUTH));
if (ad != NULL)
{
if (ad->ad_fullname != NULL)
FREE (ad->ad_fullname, ad->ad_fullnamelen + 1);
if (ad->ad_servername != NULL)
FREE (ad->ad_servername, ad->ad_servernamelen + 1);
FREE (ad, sizeof (struct ad_private));
}
return NULL;
}
#ifdef EXPORT_RPC_SYMBOLS
libc_hidden_def (authdes_pk_create)
#else
libc_hidden_nolink_sunrpc (authdes_pk_create, GLIBC_2_1)
#endif
/*
* Implement the five authentication operations
*/
/*
* 1. Next Verifier
*/
/*ARGSUSED */
static void
authdes_nextverf (AUTH *auth)
{
/* what the heck am I supposed to do??? */
}
/*
* 2. Marshal
*/
static bool_t
authdes_marshal (AUTH *auth, XDR *xdrs)
{
struct ad_private *ad = AUTH_PRIVATE (auth);
struct authdes_cred *cred = &ad->ad_cred;
struct authdes_verf *verf = &ad->ad_verf;
des_block cryptbuf[2];
des_block ivec;
int status;
int len;
register int32_t *ixdr;
struct timeval tval;
/*
* Figure out the "time", accounting for any time difference
* with the server if necessary.
*/
__gettimeofday (&tval, (struct timezone *) NULL);
ad->ad_timestamp.tv_sec = tval.tv_sec + ad->ad_timediff.tv_sec;
ad->ad_timestamp.tv_usec = tval.tv_usec + ad->ad_timediff.tv_usec;
if (ad->ad_timestamp.tv_usec >= MILLION)
{
ad->ad_timestamp.tv_usec -= MILLION;
ad->ad_timestamp.tv_sec += 1;
}
/*
* XDR the timestamp and possibly some other things, then
* encrypt them.
* XXX We have a real Year 2038 problem here.
*/
ixdr = (int32_t *) cryptbuf;
IXDR_PUT_INT32 (ixdr, ad->ad_timestamp.tv_sec);
IXDR_PUT_INT32 (ixdr, ad->ad_timestamp.tv_usec);
if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
{
IXDR_PUT_U_INT32 (ixdr, ad->ad_window);
IXDR_PUT_U_INT32 (ixdr, ad->ad_window - 1);
ivec.key.high = ivec.key.low = 0;
status = cbc_crypt ((char *) &auth->ah_key, (char *) cryptbuf,
2 * sizeof (des_block), DES_ENCRYPT | DES_HW, (char *) &ivec);
}
else
status = ecb_crypt ((char *) &auth->ah_key, (char *) cryptbuf,
sizeof (des_block), DES_ENCRYPT | DES_HW);
if (DES_FAILED (status))
{
debug ("authdes_marshal: DES encryption failure");
return FALSE;
}
ad->ad_verf.adv_xtimestamp = cryptbuf[0];
if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
{
ad->ad_cred.adc_fullname.window = cryptbuf[1].key.high;
ad->ad_verf.adv_winverf = cryptbuf[1].key.low;
}
else
{
ad->ad_cred.adc_nickname = ad->ad_nickname;
ad->ad_verf.adv_winverf = 0;
}
/*
* Serialize the credential and verifier into opaque
* authentication data.
*/
if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
len = ((1 + 1 + 2 + 1) * BYTES_PER_XDR_UNIT + ad->ad_fullnamelen);
else
len = (1 + 1) * BYTES_PER_XDR_UNIT;
if ((ixdr = xdr_inline (xdrs, 2 * BYTES_PER_XDR_UNIT)) != NULL)
{
IXDR_PUT_INT32 (ixdr, AUTH_DES);
IXDR_PUT_U_INT32 (ixdr, len);
}
else
{
ATTEMPT (xdr_putint32 (xdrs, &auth->ah_cred.oa_flavor));
ATTEMPT (xdr_putint32 (xdrs, &len));
}
ATTEMPT (xdr_authdes_cred (xdrs, cred));
len = (2 + 1) * BYTES_PER_XDR_UNIT;
if ((ixdr = xdr_inline (xdrs, 2 * BYTES_PER_XDR_UNIT)) != NULL)
{
IXDR_PUT_INT32 (ixdr, AUTH_DES);
IXDR_PUT_U_INT32 (ixdr, len);
}
else
{
ATTEMPT (xdr_putint32 (xdrs, &auth->ah_verf.oa_flavor));
ATTEMPT (xdr_putint32 (xdrs, &len));
}
ATTEMPT (xdr_authdes_verf (xdrs, verf));
return TRUE;
}
/*
* 3. Validate
*/
static bool_t
authdes_validate (AUTH *auth, struct opaque_auth *rverf)
{
struct ad_private *ad = AUTH_PRIVATE (auth);
struct authdes_verf verf;
int status;
register uint32_t *ixdr;
if (rverf->oa_length != (2 + 1) * BYTES_PER_XDR_UNIT)
return FALSE;
ixdr = (uint32_t *) rverf->oa_base;
verf.adv_xtimestamp.key.high = *ixdr++;
verf.adv_xtimestamp.key.low = *ixdr++;
verf.adv_int_u = *ixdr++; /* nickname not XDR'd ! */
/*
* Decrypt the timestamp
*/
status = ecb_crypt ((char *) &auth->ah_key, (char *) &verf.adv_xtimestamp,
sizeof (des_block), DES_DECRYPT | DES_HW);
if (DES_FAILED (status))
{
debug ("authdes_validate: DES decryption failure");
return FALSE;
}
/*
* xdr the decrypted timestamp
*/
ixdr = (uint32_t *) verf.adv_xtimestamp.c;
verf.adv_timestamp.tv_sec = IXDR_GET_U_INT32 (ixdr) + 1;
verf.adv_timestamp.tv_usec = IXDR_GET_U_INT32 (ixdr);
/*
* validate
*/
if (memcmp ((char *) &ad->ad_timestamp, (char *) &verf.adv_timestamp,
sizeof (struct rpc_timeval)) != 0)
{
debug ("authdes_validate: verifier mismatch\n");
return FALSE;
}
/*
* We have a nickname now, let's use it
*/
ad->ad_nickname = verf.adv_nickname;
ad->ad_cred.adc_namekind = ADN_NICKNAME;
return TRUE;
}
/*
* 4. Refresh
*/
static bool_t
authdes_refresh (AUTH *auth)
{
netobj pkey;
struct ad_private *ad = AUTH_PRIVATE (auth);
struct authdes_cred *cred = &ad->ad_cred;
if (ad->ad_dosync && !synchronize (&ad->ad_syncaddr, &ad->ad_timediff))
{
/*
* Hope the clocks are synced!
*/
ad->ad_timediff.tv_sec = ad->ad_timediff.tv_usec = 0;
debug ("authdes_refresh: unable to synchronize with server");
}
ad->ad_xkey = auth->ah_key;
pkey.n_bytes = (char *) (ad->ad_pkey);
pkey.n_len = strlen ((char *) ad->ad_pkey) + 1;
if (key_encryptsession_pk (ad->ad_servername, &pkey, &ad->ad_xkey) < 0)
{
debug ("authdes_create: unable to encrypt conversation key");
return FALSE;
}
cred->adc_fullname.key = ad->ad_xkey;
cred->adc_namekind = ADN_FULLNAME;
cred->adc_fullname.name = ad->ad_fullname;
return TRUE;
}
/*
* 5. Destroy
*/
static void
authdes_destroy (AUTH *auth)
{
struct ad_private *ad = AUTH_PRIVATE (auth);
FREE (ad->ad_fullname, ad->ad_fullnamelen + 1);
FREE (ad->ad_servername, ad->ad_servernamelen + 1);
FREE (ad, sizeof (struct ad_private));
FREE (auth, sizeof (AUTH));
}
/*
* Synchronize with the server at the given address, that is,
* adjust timep to reflect the delta between our clocks
*/
static bool_t
synchronize (struct sockaddr *syncaddr, struct rpc_timeval *timep)
{
struct timeval mytime;
struct rpc_timeval timeout;
timeout.tv_sec = RTIME_TIMEOUT;
timeout.tv_usec = 0;
if (rtime ((struct sockaddr_in *) syncaddr, timep, &timeout) < 0)
return FALSE;
__gettimeofday (&mytime, (struct timezone *) NULL);
timep->tv_sec -= mytime.tv_sec;
if (mytime.tv_usec > timep->tv_usec)
{
timep->tv_sec -= 1;
timep->tv_usec += MILLION;
}
timep->tv_usec -= mytime.tv_usec;
return TRUE;
}