lib/libc/rpc/svc_auth.c

   1 /*
   2  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
   3  * unrestricted use provided that this legend is included on all tape
   4  * media and as a part of the software program in whole or part.  Users
   5  * may copy or modify Sun RPC without charge, but are not authorized
   6  * to license or distribute it to anyone else except as part of a product or
   7  * program developed by the user.
   8  *
   9  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  10  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  11  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  12  *
  13  * Sun RPC is provided with no support and without any obligation on the
  14  * part of Sun Microsystems, Inc. to assist in its use, correction,
  15  * modification or enhancement.
  16  *
  17  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  18  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  19  * OR ANY PART THEREOF.
  20  *
  21  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  22  * or profits or other special, indirect and consequential damages, even if
  23  * Sun has been advised of the possibility of such damages.
  24  *
  25  * Sun Microsystems, Inc.
  26  * 2550 Garcia Avenue
  27  * Mountain View, California  94043
  28  *
  29  * @(#)svc_auth.c       1.16    94/04/24 SMI; 1.26 89/02/07 Copyr 1984 Sun Micro
  30  * $NetBSD: svc_auth.c,v 1.12 2000/07/06 03:10:35 christos Exp $
  31  * $FreeBSD: src/lib/libc/rpc/svc_auth.c,v 1.13 2006/02/27 22:10:59 deischen Exp $
  32  * $DragonFly: src/lib/libc/rpc/svc_auth.c,v 1.4 2005/11/13 12:27:04 swildner Exp $
  33  */
  34 /*
  35  * Copyright (c) 1986-1991 by Sun Microsystems Inc.
  36  */
  37
  38 /*
  39  * svc_auth.c, Server-side rpc authenticator interface.
  40  */
  41
  42 #include "namespace.h"
  43 #include "reentrant.h"
  44 #include <sys/types.h>
  45 #include <rpc/rpc.h>
  46 #include <stdlib.h>
  47 #include "un-namespace.h"
  48 #include "mt_misc.h"
  49
  50 /*
  51  * svcauthsw is the bdevsw of server side authentication.
  52  *
  53  * Server side authenticators are called from authenticate by
  54  * using the client auth struct flavor field to index into svcauthsw.
  55  * The server auth flavors must implement a routine that looks
  56  * like:
  57  *
  58  *      enum auth_stat
  59  *      flavorx_auth(rqst, msg)
  60  *              struct svc_req *rqst;
  61  *              struct rpc_msg *msg;
  62  *
  63  */
  64
  65 /* declarations to allow servers to specify new authentication flavors */
  66 struct authsvc {
  67         int     flavor;
  68         enum    auth_stat (*handler)(struct svc_req *, struct rpc_msg *);
  69         struct  authsvc   *next;
  70 };
  71 static struct authsvc *Auths = NULL;
  72
  73 /*
  74  * The call rpc message, msg has been obtained from the wire.  The msg contains
  75  * the raw form of credentials and verifiers.  authenticate returns AUTH_OK
  76  * if the msg is successfully authenticated.  If AUTH_OK then the routine also
  77  * does the following things:
  78  * set rqst->rq_xprt->verf to the appropriate response verifier;
  79  * sets rqst->rq_client_cred to the "cooked" form of the credentials.
  80  *
  81  * NB: rqst->rq_cxprt->verf must be pre-alloctaed;
  82  * its length is set appropriately.
  83  *
  84  * The caller still owns and is responsible for msg->u.cmb.cred and
  85  * msg->u.cmb.verf.  The authentication system retains ownership of
  86  * rqst->rq_client_cred, the cooked credentials.
  87  *
  88  * There is an assumption that any flavour less than AUTH_NULL is
  89  * invalid.
  90  */
  91 enum auth_stat
  92 _authenticate(struct svc_req *rqst, struct rpc_msg *msg)
  93 {
  94         int cred_flavor;
  95         struct authsvc *asp;
  96         enum auth_stat dummy;
  97
  98 /* VARIABLES PROTECTED BY authsvc_lock: asp, Auths */
  99
 100         rqst->rq_cred = msg->rm_call.cb_cred;
 101         rqst->rq_xprt->xp_verf.oa_flavor = _null_auth.oa_flavor;
 102         rqst->rq_xprt->xp_verf.oa_length = 0;
 103         cred_flavor = rqst->rq_cred.oa_flavor;
 104         switch (cred_flavor) {
 105         case AUTH_NULL:
 106                 dummy = _svcauth_null(rqst, msg);
 107                 return (dummy);
 108         case AUTH_SYS:
 109                 dummy = _svcauth_unix(rqst, msg);
 110                 return (dummy);
 111         case AUTH_SHORT:
 112                 dummy = _svcauth_short(rqst, msg);
 113                 return (dummy);
 114 #ifdef DES_BUILTIN
 115         case AUTH_DES:
 116                 dummy = _svcauth_des(rqst, msg);
 117                 return (dummy);
 118 #endif
 119         default:
 120                 break;
 121         }
 122
 123         /* flavor doesn't match any of the builtin types, so try new ones */
 124         mutex_lock(&authsvc_lock);
 125         for (asp = Auths; asp; asp = asp->next) {
 126                 if (asp->flavor == cred_flavor) {
 127                         enum auth_stat as;
 128
 129                         as = (*asp->handler)(rqst, msg);
 130                         mutex_unlock(&authsvc_lock);
 131                         return (as);
 132                 }
 133         }
 134         mutex_unlock(&authsvc_lock);
 135
 136         return (AUTH_REJECTEDCRED);
 137 }
 138
 139 /*ARGSUSED*/
 140 enum auth_stat
 141 _svcauth_null(struct svc_req *rqst, struct rpc_msg *msg)
 142 {
 143         return (AUTH_OK);
 144 }
 145
 146 /*
 147  *  Allow the rpc service to register new authentication types that it is
 148  *  prepared to handle.  When an authentication flavor is registered,
 149  *  the flavor is checked against already registered values.  If not
 150  *  registered, then a new Auths entry is added on the list.
 151  *
 152  *  There is no provision to delete a registration once registered.
 153  *
 154  *  This routine returns:
 155  *       0 if registration successful
 156  *       1 if flavor already registered
 157  *      -1 if can't register (errno set)
 158  */
 159
 160 int
 161 svc_auth_reg(int cred_flavor,
 162              enum auth_stat (*handler)(struct svc_req *, struct rpc_msg *))
 163 {
 164         struct authsvc *asp;
 165
 166         switch (cred_flavor) {
 167             case AUTH_NULL:
 168             case AUTH_SYS:
 169             case AUTH_SHORT:
 170 #ifdef DES_BUILTIN
 171             case AUTH_DES:
 172 #endif
 173                 /* already registered */
 174                 return (1);
 175
 176             default:
 177                 mutex_lock(&authsvc_lock);
 178                 for (asp = Auths; asp; asp = asp->next) {
 179                         if (asp->flavor == cred_flavor) {
 180                                 /* already registered */
 181                                 mutex_unlock(&authsvc_lock);
 182                                 return (1);
 183                         }
 184                 }
 185
 186                 /* this is a new one, so go ahead and register it */
 187                 asp = mem_alloc(sizeof (*asp));
 188                 if (asp == NULL) {
 189                         mutex_unlock(&authsvc_lock);
 190                         return (-1);
 191                 }
 192                 asp->flavor = cred_flavor;
 193                 asp->handler = handler;
 194                 asp->next = Auths;
 195                 Auths = asp;
 196                 mutex_unlock(&authsvc_lock);
 197                 break;
 198         }
 199         return (0);
 200 }