sunrpc/svc_auth.c

   1 /*
   2  * svc_auth.c, Server-side rpc authenticator interface.
   3  *
   4  * Copyright (c) 2010, Oracle America, Inc.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions are
   8  * met:
   9  *
  10  *     * Redistributions of source code must retain the above copyright
  11  *       notice, this list of conditions and the following disclaimer.
  12  *     * Redistributions in binary form must reproduce the above
  13  *       copyright notice, this list of conditions and the following
  14  *       disclaimer in the documentation and/or other materials
  15  *       provided with the distribution.
  16  *     * Neither the name of the "Oracle America, Inc." nor the names of its
  17  *       contributors may be used to endorse or promote products derived
  18  *       from this software without specific prior written permission.
  19  *
  20  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  21  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  22  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  23  *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  24  *   COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
  25  *   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  *   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
  27  *   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  28  *   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  29  *   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  30  *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 #include <rpc/rpc.h>
  35 #include <rpc/svc.h>
  36 #include <rpc/svc_auth.h>
  37 #include <shlib-compat.h>
  38
  39 /*
  40  * svcauthsw is the bdevsw of server side authentication.
  41  *
  42  * Server side authenticators are called from authenticate by
  43  * using the client auth struct flavor field to index into svcauthsw.
  44  * The server auth flavors must implement a routine that looks
  45  * like:
  46  *
  47  *      enum auth_stat
  48  *      flavorx_auth(rqst, msg)
  49  *              register struct svc_req *rqst;
  50  *              register struct rpc_msg *msg;
  51  *
  52  */
  53
  54 static enum auth_stat _svcauth_null (struct svc_req *, struct rpc_msg *);
  55                                 /* no authentication */
  56 extern enum auth_stat _svcauth_unix (struct svc_req *, struct rpc_msg *);
  57                                 /* unix style (uid, gids) */
  58 extern enum auth_stat _svcauth_short (struct svc_req *, struct rpc_msg *);
  59                                 /* short hand unix style */
  60 extern enum auth_stat _svcauth_des (struct svc_req *, struct rpc_msg *);
  61                                 /* des style */
  62
  63 static const struct
  64   {
  65     enum auth_stat (*authenticator) (struct svc_req *, struct rpc_msg *);
  66   }
  67 svcauthsw[] =
  68 {
  69   { _svcauth_null },            /* AUTH_NULL */
  70   { _svcauth_unix },            /* AUTH_UNIX */
  71   { _svcauth_short },           /* AUTH_SHORT */
  72   { _svcauth_des }              /* AUTH_DES */
  73 };
  74 #define AUTH_MAX        3       /* HIGHEST AUTH NUMBER */
  75
  76
  77 /*
  78  * The call rpc message, msg has been obtained from the wire.  The msg contains
  79  * the raw form of credentials and verifiers.  authenticate returns AUTH_OK
  80  * if the msg is successfully authenticated.  If AUTH_OK then the routine also
  81  * does the following things:
  82  * set rqst->rq_xprt->verf to the appropriate response verifier;
  83  * sets rqst->rq_client_cred to the "cooked" form of the credentials.
  84  *
  85  * NB: rqst->rq_cxprt->verf must be pre-allocated;
  86  * its length is set appropriately.
  87  *
  88  * The caller still owns and is responsible for msg->u.cmb.cred and
  89  * msg->u.cmb.verf.  The authentication system retains ownership of
  90  * rqst->rq_client_cred, the cooked credentials.
  91  *
  92  * There is an assumption that any flavour less than AUTH_NULL is
  93  * invalid.
  94  */
  95 enum auth_stat
  96 _authenticate (register struct svc_req *rqst, struct rpc_msg *msg)
  97 {
  98   register int cred_flavor;
  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   if ((cred_flavor <= AUTH_MAX) && (cred_flavor >= AUTH_NULL))
 105     return (*(svcauthsw[cred_flavor].authenticator)) (rqst, msg);
 106
 107   return AUTH_REJECTEDCRED;
 108 }
 109 libc_hidden_nolink_sunrpc (_authenticate, GLIBC_2_1)
 110
 111 static enum auth_stat
 112 _svcauth_null (struct svc_req *rqst, struct rpc_msg *msg)
 113 {
 114   return AUTH_OK;
 115 }