/* $NetBSD: auth_unix.c,v 1.18 2000/07/06 03:03:30 christos Exp $ */
/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 2009, Sun Microsystems, Inc.
* All rights reserved.
*
* 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 Sun Microsystems, 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char *sccsid2 = "@(#)auth_unix.c 1.19 87/08/11 Copyr 1984 Sun Micro";
static char *sccsid = "@(#)auth_unix.c 2.2 88/08/01 4.0 RPCSRC";
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* auth_unix.c, Implements UNIX style authentication parameters.
*
* Copyright (C) 1984, Sun Microsystems, Inc.
*
* The system is very weak. The client uses no encryption for it's
* credentials and only sends null verifiers. The server sends backs
* null verifiers or optionally a verifier that suggests a new short hand
* for the credentials.
*
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/hash.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/pcpu.h>
#include <sys/refcount.h>
#include <sys/sx.h>
#include <sys/ucred.h>
#include <rpc/types.h>
#include <rpc/xdr.h>
#include <rpc/auth.h>
#include <rpc/clnt.h>
#include <rpc/rpc_com.h>
/* auth_unix.c */
static void authunix_nextverf (AUTH *);
static bool_t authunix_marshal (AUTH *, uint32_t, XDR *, struct mbuf *);
static bool_t authunix_validate (AUTH *, uint32_t, struct opaque_auth *,
struct mbuf **);
static bool_t authunix_refresh (AUTH *, void *);
static void authunix_destroy (AUTH *);
static void marshal_new_auth (AUTH *);
static struct auth_ops authunix_ops = {
.ah_nextverf = authunix_nextverf,
.ah_marshal = authunix_marshal,
.ah_validate = authunix_validate,
.ah_refresh = authunix_refresh,
.ah_destroy = authunix_destroy,
};
/*
* This struct is pointed to by the ah_private field of an auth_handle.
*/
struct audata {
TAILQ_ENTRY(audata) au_link;
TAILQ_ENTRY(audata) au_alllink;
volatile u_int au_refs;
struct xucred au_xcred;
struct opaque_auth au_origcred; /* original credentials */
struct opaque_auth au_shcred; /* short hand cred */
u_long au_shfaults; /* short hand cache faults */
char au_marshed[MAX_AUTH_BYTES];
u_int au_mpos; /* xdr pos at end of marshed */
AUTH *au_auth; /* link back to AUTH */
};
TAILQ_HEAD(audata_list, audata);
#define AUTH_PRIVATE(auth) ((struct audata *)auth->ah_private)
#define AUTH_UNIX_HASH_SIZE 16
#define AUTH_UNIX_MAX 256
static struct audata_list auth_unix_cache[AUTH_UNIX_HASH_SIZE];
static struct audata_list auth_unix_all;
static struct sx auth_unix_lock;
static int auth_unix_count;
static void
authunix_init(void *dummy)
{
int i;
for (i = 0; i < AUTH_UNIX_HASH_SIZE; i++)
TAILQ_INIT(&auth_unix_cache[i]);
TAILQ_INIT(&auth_unix_all);
sx_init(&auth_unix_lock, "auth_unix_lock");
}
SYSINIT(authunix_init, SI_SUB_KMEM, SI_ORDER_ANY, authunix_init, NULL);
/*
* Create a unix style authenticator.
* Returns an auth handle with the given stuff in it.
*/
AUTH *
authunix_create(struct ucred *cred)
{
uint32_t h, th;
struct xucred xcr;
char mymem[MAX_AUTH_BYTES];
XDR xdrs;
AUTH *auth;
struct audata *au, *tau;
struct timeval now;
uint32_t time;
int len;
if (auth_unix_count > AUTH_UNIX_MAX) {
while (auth_unix_count > AUTH_UNIX_MAX) {
sx_xlock(&auth_unix_lock);
tau = TAILQ_FIRST(&auth_unix_all);
th = HASHSTEP(HASHINIT, tau->au_xcred.cr_uid)
% AUTH_UNIX_HASH_SIZE;
TAILQ_REMOVE(&auth_unix_cache[th], tau, au_link);
TAILQ_REMOVE(&auth_unix_all, tau, au_alllink);
auth_unix_count--;
sx_xunlock(&auth_unix_lock);
AUTH_DESTROY(tau->au_auth);
}
}
/*
* Hash the uid to see if we already have an AUTH with this cred.
*/
h = HASHSTEP(HASHINIT, cred->cr_uid) % AUTH_UNIX_HASH_SIZE;
cru2x(cred, &xcr);
again:
sx_slock(&auth_unix_lock);
TAILQ_FOREACH(au, &auth_unix_cache[h], au_link) {
if (!memcmp(&xcr, &au->au_xcred, sizeof(xcr))) {
refcount_acquire(&au->au_refs);
if (sx_try_upgrade(&auth_unix_lock)) {
/*
* Keep auth_unix_all LRU sorted.
*/
TAILQ_REMOVE(&auth_unix_all, au, au_alllink);
TAILQ_INSERT_TAIL(&auth_unix_all, au,
au_alllink);
sx_xunlock(&auth_unix_lock);
} else {
sx_sunlock(&auth_unix_lock);
}
return (au->au_auth);
}
}
sx_sunlock(&auth_unix_lock);
/*
* Allocate and set up auth handle
*/
au = NULL;
auth = mem_alloc(sizeof(*auth));
au = mem_alloc(sizeof(*au));
auth->ah_ops = &authunix_ops;
auth->ah_private = (caddr_t)au;
auth->ah_verf = au->au_shcred = _null_auth;
refcount_init(&au->au_refs, 1);
au->au_xcred = xcr;
au->au_shfaults = 0;
au->au_origcred.oa_base = NULL;
au->au_auth = auth;
getmicrotime(&now);
time = now.tv_sec;
/*
* Serialize the parameters into origcred
*/
xdrmem_create(&xdrs, mymem, MAX_AUTH_BYTES, XDR_ENCODE);
cru2x(cred, &xcr);
if (! xdr_authunix_parms(&xdrs, &time, &xcr))
panic("authunix_create: failed to encode creds");
au->au_origcred.oa_length = len = XDR_GETPOS(&xdrs);
au->au_origcred.oa_flavor = AUTH_UNIX;
au->au_origcred.oa_base = mem_alloc((u_int) len);
memcpy(au->au_origcred.oa_base, mymem, (size_t)len);
/*
* set auth handle to reflect new cred.
*/
auth->ah_cred = au->au_origcred;
marshal_new_auth(auth);
sx_xlock(&auth_unix_lock);
TAILQ_FOREACH(tau, &auth_unix_cache[h], au_link) {
if (!memcmp(&xcr, &tau->au_xcred, sizeof(xcr))) {
/*
* We lost a race to create the AUTH that
* matches this cred.
*/
sx_xunlock(&auth_unix_lock);
AUTH_DESTROY(auth);
goto again;
}
}
auth_unix_count++;
TAILQ_INSERT_TAIL(&auth_unix_cache[h], au, au_link);
TAILQ_INSERT_TAIL(&auth_unix_all, au, au_alllink);
refcount_acquire(&au->au_refs); /* one for the cache, one for user */
sx_xunlock(&auth_unix_lock);
return (auth);
}
/*
* authunix operations
*/
/* ARGSUSED */
static void
authunix_nextverf(AUTH *auth)
{
/* no action necessary */
}
static bool_t
authunix_marshal(AUTH *auth, uint32_t xid, XDR *xdrs, struct mbuf *args)
{
struct audata *au;
au = AUTH_PRIVATE(auth);
if (!XDR_PUTBYTES(xdrs, au->au_marshed, au->au_mpos))
return (FALSE);
xdrmbuf_append(xdrs, args);
return (TRUE);
}
static bool_t
authunix_validate(AUTH *auth, uint32_t xid, struct opaque_auth *verf,
struct mbuf **mrepp)
{
struct audata *au;
XDR txdrs;
if (!verf)
return (TRUE);
if (verf->oa_flavor == AUTH_SHORT) {
au = AUTH_PRIVATE(auth);
xdrmem_create(&txdrs, verf->oa_base, verf->oa_length,
XDR_DECODE);
if (au->au_shcred.oa_base != NULL) {
mem_free(au->au_shcred.oa_base,
au->au_shcred.oa_length);
au->au_shcred.oa_base = NULL;
}
if (xdr_opaque_auth(&txdrs, &au->au_shcred)) {
auth->ah_cred = au->au_shcred;
} else {
txdrs.x_op = XDR_FREE;
(void)xdr_opaque_auth(&txdrs, &au->au_shcred);
au->au_shcred.oa_base = NULL;
auth->ah_cred = au->au_origcred;
}
marshal_new_auth(auth);
}
return (TRUE);
}
static bool_t
authunix_refresh(AUTH *auth, void *dummy)
{
struct audata *au = AUTH_PRIVATE(auth);
struct xucred xcr;
uint32_t time;
struct timeval now;
XDR xdrs;
int stat;
if (auth->ah_cred.oa_base == au->au_origcred.oa_base) {
/* there is no hope. Punt */
return (FALSE);
}
au->au_shfaults ++;
/* first deserialize the creds back into a struct ucred */
xdrmem_create(&xdrs, au->au_origcred.oa_base,
au->au_origcred.oa_length, XDR_DECODE);
stat = xdr_authunix_parms(&xdrs, &time, &xcr);
if (! stat)
goto done;
/* update the time and serialize in place */
getmicrotime(&now);
time = now.tv_sec;
xdrs.x_op = XDR_ENCODE;
XDR_SETPOS(&xdrs, 0);
stat = xdr_authunix_parms(&xdrs, &time, &xcr);
if (! stat)
goto done;
auth->ah_cred = au->au_origcred;
marshal_new_auth(auth);
done:
XDR_DESTROY(&xdrs);
return (stat);
}
static void
authunix_destroy(AUTH *auth)
{
struct audata *au;
au = AUTH_PRIVATE(auth);
if (!refcount_release(&au->au_refs))
return;
mem_free(au->au_origcred.oa_base, au->au_origcred.oa_length);
if (au->au_shcred.oa_base != NULL)
mem_free(au->au_shcred.oa_base, au->au_shcred.oa_length);
mem_free(auth->ah_private, sizeof(struct audata));
if (auth->ah_verf.oa_base != NULL)
mem_free(auth->ah_verf.oa_base, auth->ah_verf.oa_length);
mem_free(auth, sizeof(*auth));
}
/*
* Marshals (pre-serializes) an auth struct.
* sets private data, au_marshed and au_mpos
*/
static void
marshal_new_auth(AUTH *auth)
{
XDR xdr_stream;
XDR *xdrs = &xdr_stream;
struct audata *au;
au = AUTH_PRIVATE(auth);
xdrmem_create(xdrs, au->au_marshed, MAX_AUTH_BYTES, XDR_ENCODE);
if ((! xdr_opaque_auth(xdrs, &(auth->ah_cred))) ||
(! xdr_opaque_auth(xdrs, &(auth->ah_verf))))
printf("auth_none.c - Fatal marshalling problem");
else
au->au_mpos = XDR_GETPOS(xdrs);
XDR_DESTROY(xdrs);
}
