usr/src/lib/libc/port/nsl/svc_auth.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22
  23 /*
  24  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
  25  * Use is subject to license terms.
  26  */
  27 /* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
  28 /* All Rights Reserved */
  29 /*
  30  * Portions of this source code were derived from Berkeley
  31  * 4.3 BSD under license from the Regents of the University of
  32  * California.
  33  */
  34
  35 #pragma ident   "%Z%%M% %I%     %E% SMI"
  36
  37 /*
  38  * svc_auth.c, Server-side rpc authenticator interface.
  39  *
  40  */
  41
  42 #include "mt.h"
  43 #include "rpc_mt.h"
  44 #include <rpc/rpc.h>
  45 #include <sys/types.h>
  46 #include <stdlib.h>
  47
  48 /*
  49  * svcauthsw is the bdevsw of server side authentication.
  50  *
  51  * Server side authenticators are called from authenticate by
  52  * using the client auth struct flavor field to index into svcauthsw.
  53  * The server auth flavors must implement a routine that looks
  54  * like:
  55  *
  56  *      enum auth_stat
  57  *      flavorx_auth(rqst, msg)
  58  *              struct svc_req *rqst;
  59  *              struct rpc_msg *msg;
  60  *
  61  * The RPCSEC_GSS flavor is an exception.  Its routine takes an
  62  * additional boolean parameter that gets set to TRUE when the call
  63  * is not to be dispatched to the server.
  64  */
  65
  66 enum auth_stat __svcauth_null();        /* no authentication */
  67 enum auth_stat __svcauth_sys();         /* (system) unix style (uid, gids) */
  68 enum auth_stat __svcauth_short();       /* short hand unix style */
  69 enum auth_stat __svcauth_des();         /* des style */
  70 enum auth_stat __svcauth_loopback();    /* (loopback) unix style (uid, gids) */
  71 extern enum auth_stat __svcrpcsec_gss();        /* GSS style */
  72
  73 /* declarations to allow servers to specify new authentication flavors */
  74 struct authsvc {
  75         int     flavor;
  76         enum    auth_stat (*handler)();
  77         struct  authsvc   *next;
  78 };
  79 static struct authsvc *Auths = NULL;
  80
  81 /*
  82  * The call rpc message, msg has been obtained from the wire.  The msg contains
  83  * the raw form of credentials and verifiers.  no_dispatch is used and
  84  * dereferenced in subsequent gss function calls.  authenticate returns AUTH_OK
  85  * if the msg is successfully authenticated.  If AUTH_OK then the routine also
  86  * does the following things:
  87  * set rqst->rq_xprt->verf to the appropriate response verifier;
  88  * sets rqst->rq_client_cred to the "cooked" form of the credentials.
  89  *
  90  * NB: rqst->rq_cxprt->verf must be pre-alloctaed;
  91  * its length is set appropriately.
  92  *
  93  * The caller still owns and is responsible for msg->u.cmb.cred and
  94  * msg->u.cmb.verf.  The authentication system retains ownership of
  95  * rqst->rq_client_cred, the cooked credentials.
  96  *
  97  * There is an assumption that any flavour less than AUTH_NULL is
  98  * invalid.
  99  */
 100 enum auth_stat
 101 __gss_authenticate(struct svc_req *rqst, struct rpc_msg *msg,
 102                                                         bool_t *no_dispatch)
 103 {
 104         int cred_flavor;
 105         struct authsvc *asp;
 106         extern mutex_t authsvc_lock;
 107
 108 /* VARIABLES PROTECTED BY authsvc_lock: asp, Auths */
 109
 110         rqst->rq_cred = msg->rm_call.cb_cred;
 111         rqst->rq_xprt->xp_verf.oa_flavor = _null_auth.oa_flavor;
 112         rqst->rq_xprt->xp_verf.oa_length = 0;
 113         cred_flavor = rqst->rq_cred.oa_flavor;
 114         *no_dispatch = FALSE;
 115         switch (cred_flavor) {
 116         case AUTH_NULL:
 117                 return (__svcauth_null(rqst, msg));
 118         case AUTH_SYS:
 119                 return (__svcauth_sys(rqst, msg));
 120         case AUTH_SHORT:
 121                 return (__svcauth_short(rqst, msg));
 122         case AUTH_DES:
 123                 return (__svcauth_des(rqst, msg));
 124         case AUTH_LOOPBACK:
 125                 return (__svcauth_loopback(rqst, msg));
 126         case RPCSEC_GSS:
 127                 return (__svcrpcsec_gss(rqst, msg, no_dispatch));
 128         }
 129
 130         /* flavor doesn't match any of the builtin types, so try new ones */
 131         (void) mutex_lock(&authsvc_lock);
 132         for (asp = Auths; asp; asp = asp->next) {
 133                 if (asp->flavor == cred_flavor) {
 134                         enum auth_stat as;
 135
 136                         as = (*asp->handler)(rqst, msg);
 137                         (void) mutex_unlock(&authsvc_lock);
 138                         return (as);
 139                 }
 140         }
 141         (void) mutex_unlock(&authsvc_lock);
 142
 143         return (AUTH_REJECTEDCRED);
 144 }
 145
 146 /*
 147  * The following function __authenticate(rqst, msg) is preserved for
 148  * backward compatibility.
 149  */
 150 enum auth_stat
 151 __authenticate(struct svc_req *rqst, struct rpc_msg *msg)
 152 {
 153         bool_t no_dispatch;
 154
 155         return (__gss_authenticate(rqst, msg, &no_dispatch));
 156 }
 157
 158 /*ARGSUSED*/
 159 enum auth_stat
 160 __svcauth_null(struct svc_req *rqst, struct rpc_msg *msg)
 161 {
 162         return (AUTH_OK);
 163 }
 164
 165 /*
 166  *  Allow the rpc service to register new authentication types that it is
 167  *  prepared to handle.  When an authentication flavor is registered,
 168  *  the flavor is checked against already registered values.  If not
 169  *  registered, then a new Auths entry is added on the list.
 170  *
 171  *  There is no provision to delete a registration once registered.
 172  *
 173  *  This routine returns:
 174  *       0 if registration successful
 175  *       1 if flavor already registered
 176  *      -1 if can't register (errno set)
 177  */
 178
 179 int
 180 svc_auth_reg(int cred_flavor, enum auth_stat (*handler)())
 181 {
 182         struct authsvc *asp;
 183         extern mutex_t authsvc_lock;
 184
 185         switch (cred_flavor) {
 186         case AUTH_NULL:
 187         case AUTH_SYS:
 188         case AUTH_SHORT:
 189         case AUTH_DES:
 190         case AUTH_LOOPBACK:
 191         case RPCSEC_GSS:
 192                 /* already registered */
 193                 return (1);
 194         }
 195         (void) mutex_lock(&authsvc_lock);
 196         for (asp = Auths; asp; asp = asp->next) {
 197                 if (asp->flavor == cred_flavor) {
 198                         /* already registered */
 199                         (void) mutex_unlock(&authsvc_lock);
 200                         return (1);
 201                 }
 202         }
 203
 204         /* this is a new one, so go ahead and register it */
 205         asp = malloc(sizeof (*asp));
 206         if (asp == NULL) {
 207                 (void) mutex_unlock(&authsvc_lock);
 208                 return (-1);
 209         }
 210         asp->flavor = cred_flavor;
 211         asp->handler = handler;
 212         asp->next = Auths;
 213         Auths = asp;
 214         (void) mutex_unlock(&authsvc_lock);
 215         return (0);
 216 }