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
  38 /*
  39  * svcauthsw is the bdevsw of server side authentication.
  40  *
  41  * Server side authenticators are called from authenticate by
  42  * using the client auth struct flavor field to index into svcauthsw.
  43  * The server auth flavors must implement a routine that looks
  44  * like:
  45  *
  46  *      enum auth_stat
  47  *      flavorx_auth(rqst, msg)
  48  *              register struct svc_req *rqst;
  49  *              register struct rpc_msg *msg;
  50  *
  51  */
  52
  53 static enum auth_stat _svcauth_null (struct svc_req *, struct rpc_msg *);
  54                                 /* no authentication */
  55 extern enum auth_stat _svcauth_unix (struct svc_req *, struct rpc_msg *);
  56                                 /* unix style (uid, gids) */
  57 extern enum auth_stat _svcauth_short (struct svc_req *, struct rpc_msg *);
  58                                 /* short hand unix style */
  59 extern enum auth_stat _svcauth_des (struct svc_req *, struct rpc_msg *);
  60                                 /* des style */
  61
  62 static const struct
  63   {
  64     enum auth_stat (*authenticator) (struct svc_req *, struct rpc_msg *);
  65   }
  66 svcauthsw[] =
  67 {
  68   { _svcauth_null },            /* AUTH_NULL */
  69   { _svcauth_unix },            /* AUTH_UNIX */
  70   { _svcauth_short },           /* AUTH_SHORT */
  71   { _svcauth_des }              /* AUTH_DES */
  72 };
  73 #define AUTH_MAX        3       /* HIGHEST AUTH NUMBER */
  74
  75
  76 /*
  77  * The call rpc message, msg has been obtained from the wire.  The msg contains
  78  * the raw form of credentials and verifiers.  authenticate returns AUTH_OK
  79  * if the msg is successfully authenticated.  If AUTH_OK then the routine also
  80  * does the following things:
  81  * set rqst->rq_xprt->verf to the appropriate response verifier;
  82  * sets rqst->rq_client_cred to the "cooked" form of the credentials.
  83  *
  84  * NB: rqst->rq_cxprt->verf must be pre-allocated;
  85  * its length is set appropriately.
  86  *
  87  * The caller still owns and is responsible for msg->u.cmb.cred and
  88  * msg->u.cmb.verf.  The authentication system retains ownership of
  89  * rqst->rq_client_cred, the cooked credentials.
  90  *
  91  * There is an assumption that any flavour less than AUTH_NULL is
  92  * invalid.
  93  */
  94 enum auth_stat
  95 _authenticate (register struct svc_req *rqst, struct rpc_msg *msg)
  96 {
  97   register int cred_flavor;
  98
  99   rqst->rq_cred = msg->rm_call.cb_cred;
 100   rqst->rq_xprt->xp_verf.oa_flavor = _null_auth.oa_flavor;
 101   rqst->rq_xprt->xp_verf.oa_length = 0;
 102   cred_flavor = rqst->rq_cred.oa_flavor;
 103   if ((cred_flavor <= AUTH_MAX) && (cred_flavor >= AUTH_NULL))
 104     return (*(svcauthsw[cred_flavor].authenticator)) (rqst, msg);
 105
 106   return AUTH_REJECTEDCRED;
 107 }
 108 libc_hidden_nolink_sunrpc (_authenticate, GLIBC_2_1)
 109
 110 static enum auth_stat
 111 _svcauth_null (struct svc_req *rqst, struct rpc_msg *msg)
 112 {
 113   return AUTH_OK;
 114 }