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 1.26 89/02/07 Copyr 1984 Sun Micro
  30  * $FreeBSD: src/lib/libc/rpc/svc_auth.c,v 1.7 1999/12/29 05:04:16 peter Exp $
  31  * $DragonFly: src/lib/libc/rpc/svc_auth.c,v 1.4 2005/11/13 12:27:04 swildner Exp $
  32  */
  33 /*
  34  * Copyright (c) 1986-1991 by Sun Microsystems Inc.
  35  */
  36
  37 #ident  "@(#)svc_auth.c 1.16    94/04/24 SMI"
  38
  39 /*
  40  * svc_auth.c, Server-side rpc authenticator interface.
  41  *
  42  */
  43
  44 #ifdef _KERNEL
  45 #include <sys/param.h>
  46 #include <rpc/types.h>
  47 #include <rpc/xdr.h>
  48 #include <rpc/auth.h>
  49 #include <rpc/clnt.h>
  50 #include <rpc/rpc_msg.h>
  51 #include <rpc/svc.h>
  52 #include <rpc/svc_auth.h>
  53 #else
  54 #include <stdlib.h>
  55 #include <rpc/rpc.h>
  56 #endif
  57 #include <sys/types.h>
  58
  59 /*
  60  * svcauthsw is the bdevsw of server side authentication.
  61  *
  62  * Server side authenticators are called from authenticate by
  63  * using the client auth struct flavor field to index into svcauthsw.
  64  * The server auth flavors must implement a routine that looks
  65  * like:
  66  *
  67  *      enum auth_stat
  68  *      flavorx_auth(rqst, msg)
  69  *              struct svc_req *rqst;
  70  *              struct rpc_msg *msg;
  71  *
  72  */
  73
  74 enum auth_stat _svcauth_null(); /* no authentication */
  75 enum auth_stat _svcauth_unix();         /* (system) unix style (uid, gids) */
  76 enum auth_stat _svcauth_short();        /* short hand unix style */
  77 enum auth_stat _svcauth_des();          /* des style */
  78
  79 /* declarations to allow servers to specify new authentication flavors */
  80 struct authsvc {
  81         int     flavor;
  82         enum    auth_stat (*handler)();
  83         struct  authsvc   *next;
  84 };
  85 static struct authsvc *Auths = NULL;
  86
  87 /*
  88  * The call rpc message, msg has been obtained from the wire.  The msg contains
  89  * the raw form of credentials and verifiers.  authenticate returns AUTH_OK
  90  * if the msg is successfully authenticated.  If AUTH_OK then the routine also
  91  * does the following things:
  92  * set rqst->rq_xprt->verf to the appropriate response verifier;
  93  * sets rqst->rq_client_cred to the "cooked" form of the credentials.
  94  *
  95  * NB: rqst->rq_cxprt->verf must be pre-alloctaed;
  96  * its length is set appropriately.
  97  *
  98  * The caller still owns and is responsible for msg->u.cmb.cred and
  99  * msg->u.cmb.verf.  The authentication system retains ownership of
 100  * rqst->rq_client_cred, the cooked credentials.
 101  *
 102  * There is an assumption that any flavour less than AUTH_NULL is
 103  * invalid.
 104  */
 105 enum auth_stat
 106 _authenticate(struct svc_req *rqst, struct rpc_msg *msg)
 107 {
 108         int cred_flavor;
 109         struct authsvc *asp;
 110
 111         rqst->rq_cred = msg->rm_call.cb_cred;
 112         rqst->rq_xprt->xp_verf.oa_flavor = _null_auth.oa_flavor;
 113         rqst->rq_xprt->xp_verf.oa_length = 0;
 114         cred_flavor = rqst->rq_cred.oa_flavor;
 115         switch (cred_flavor) {
 116         case AUTH_NULL:
 117                 return(_svcauth_null(rqst, msg));
 118         case AUTH_UNIX:
 119                 return(_svcauth_unix(rqst, msg));
 120         case AUTH_SHORT:
 121                 return(_svcauth_short(rqst, msg));
 122         /*
 123          * We leave AUTH_DES turned off by default because svcauth_des()
 124          * needs getpublickey(), which is in librpcsvc, not libc. If we
 125          * included AUTH_DES as a built-in flavor, programs that don't
 126          * have -lrpcsvc in their Makefiles wouldn't link correctly, even
 127          * though they don't use AUTH_DES. And I'm too lazy to go through
 128          * the tree looking for all of them.
 129          */
 130 #ifdef DES_BUILTIN
 131         case AUTH_DES:
 132                 return(_svcauth_des(rqst, msg));
 133 #endif
 134         }
 135
 136         /* flavor doesn't match any of the builtin types, so try new ones */
 137         for (asp = Auths; asp; asp = asp->next) {
 138                 if (asp->flavor == cred_flavor) {
 139                         enum auth_stat as;
 140
 141                         as = (*asp->handler)(rqst, msg);
 142                         return (as);
 143                 }
 144         }
 145
 146         return (AUTH_REJECTEDCRED);
 147 }
 148
 149 /*ARGSUSED*/
 150 enum auth_stat
 151 _svcauth_null(struct svc_req *rqst, struct rpc_msg *msg)
 152 {
 153         return (AUTH_OK);
 154 }
 155
 156 /*
 157  *  Allow the rpc service to register new authentication types that it is
 158  *  prepared to handle.  When an authentication flavor is registered,
 159  *  the flavor is checked against already registered values.  If not
 160  *  registered, then a new Auths entry is added on the list.
 161  *
 162  *  There is no provision to delete a registration once registered.
 163  *
 164  *  This routine returns:
 165  *       0 if registration successful
 166  *       1 if flavor already registered
 167  *      -1 if can't register (errno set)
 168  */
 169
 170 int
 171 svc_auth_reg(int cred_flavor, enum auth_stat (*handler)())
 172 {
 173         struct authsvc *asp;
 174
 175         switch (cred_flavor) {
 176             case AUTH_NULL:
 177             case AUTH_UNIX:
 178             case AUTH_SHORT:
 179 #ifdef DES_BUILTIN
 180             case AUTH_DES:
 181 #endif
 182                 /* already registered */
 183                 return (1);
 184
 185             default:
 186                 for (asp = Auths; asp; asp = asp->next) {
 187                         if (asp->flavor == cred_flavor) {
 188                                 /* already registered */
 189                                 return (1);
 190                         }
 191                 }
 192
 193                 /* this is a new one, so go ahead and register it */
 194                 asp = (struct authsvc *)mem_alloc(sizeof (*asp));
 195                 if (asp == NULL) {
 196                         return (-1);
 197                 }
 198                 asp->flavor = cred_flavor;
 199                 asp->handler = handler;
 200                 asp->next = Auths;
 201                 Auths = asp;
 202                 break;
 203         }
 204         return (0);
 205 }