xref: /freebsd/crypto/krb5/src/lib/rpc/svc_auth_unix.c (revision 7f2fe78b9dd5f51c821d771b63d2e096f6fd49e9)

/* @(#)svc_auth_unix.c	2.3 88/08/01 4.0 RPCSRC; from 1.28 88/02/08 SMI */
/*
 * Copyright (c) 2010, Oracle America, 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 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.
 */
#if !defined(lint) && defined(SCCSIDS)
static char sccsid[] = "@(#)svc_auth_unix.c 1.28 88/02/08 Copyr 1984 Sun Micro";
#endif

/*
 * svc_auth_unix.c
 * Handles UNIX flavor authentication parameters on the service side of rpc.
 * There are two svc auth implementations here: AUTH_UNIX and AUTH_SHORT.
 * _svcauth_unix does full blown unix style uid,gid+gids auth,
 * _svcauth_short uses a shorthand auth to index into a cache of longhand auths.
 * Note: the shorthand has been gutted for efficiency.
 */

#include <stdio.h>
#include <string.h>
#include <gssrpc/rpc.h>

/*
 * Unix longhand authenticator
 */
enum auth_stat
gssrpc__svcauth_unix(
	struct svc_req *rqst,
	struct rpc_msg *msg,
	bool_t *dispatch)
{
	enum auth_stat stat;
	XDR xdrs;
	struct authunix_parms *aup;
	rpc_inline_t *buf;
	struct area {
		struct authunix_parms area_aup;
		char area_machname[MAX_MACHINE_NAME+1];
		int area_gids[NGRPS];
	} *area;
	u_int auth_len, str_len, gid_len, i;

	rqst->rq_xprt->xp_auth = &svc_auth_none;

	area = (struct area *) rqst->rq_clntcred;
	aup = &area->area_aup;
	aup->aup_machname = area->area_machname;
	aup->aup_gids = area->area_gids;
	auth_len = msg->rm_call.cb_cred.oa_length;
	if (auth_len > INT_MAX)
		return AUTH_BADCRED;
	xdrmem_create(&xdrs, msg->rm_call.cb_cred.oa_base, auth_len,XDR_DECODE);
	buf = XDR_INLINE(&xdrs, (int)auth_len);
	if (buf != NULL) {
		aup->aup_time = IXDR_GET_LONG(buf);
		str_len = IXDR_GET_U_LONG(buf);
		if (str_len > MAX_MACHINE_NAME) {
			stat = AUTH_BADCRED;
			goto done;
		}
		memmove(aup->aup_machname, buf, str_len);
		aup->aup_machname[str_len] = 0;
		str_len = RNDUP(str_len);
		buf += str_len / BYTES_PER_XDR_UNIT;
		aup->aup_uid = IXDR_GET_LONG(buf);
		aup->aup_gid = IXDR_GET_LONG(buf);
		gid_len = IXDR_GET_U_LONG(buf);
		if (gid_len > NGRPS) {
			stat = AUTH_BADCRED;
			goto done;
		}
		aup->aup_len = gid_len;
		for (i = 0; i < gid_len; i++) {
			aup->aup_gids[i] = IXDR_GET_LONG(buf);
		}
		/*
		 * five is the smallest unix credentials structure -
		 * timestamp, hostname len (0), uid, gid, and gids len (0).
		 */
		if ((5 + gid_len) * BYTES_PER_XDR_UNIT + str_len > auth_len) {
			(void) printf("bad auth_len gid %u str %u auth %u\n",
			    gid_len, str_len, auth_len);
			stat = AUTH_BADCRED;
			goto done;
		}
	} else if (! xdr_authunix_parms(&xdrs, aup)) {
		xdrs.x_op = XDR_FREE;
		(void)xdr_authunix_parms(&xdrs, aup);
		stat = AUTH_BADCRED;
		goto done;
	}
	rqst->rq_xprt->xp_verf.oa_flavor = AUTH_NULL;
	rqst->rq_xprt->xp_verf.oa_length = 0;
	stat = AUTH_OK;
done:
	XDR_DESTROY(&xdrs);
	return (stat);
}


/*
 * Shorthand unix authenticator
 * Looks up longhand in a cache.
 */
/*ARGSUSED*/
enum auth_stat
gssrpc__svcauth_short(
	struct svc_req *rqst,
	struct rpc_msg *msg,
	bool_t *dispatch)
{
	rqst->rq_xprt->xp_auth = &svc_auth_none;
	return (AUTH_REJECTEDCRED);
}