LXR linux/net/sunrpc/auth

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * linux/net/sunrpc/auth_null.c
   4 *
   5 * AUTH_NULL authentication. Really :-)
   6 *
   7 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
   8 */
   9
  10#include <linux/types.h>
  11#include <linux/module.h>
  12#include <linux/sunrpc/clnt.h>
  13
  14#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
  15# define RPCDBG_FACILITY        RPCDBG_AUTH
  16#endif
  17
  18static struct rpc_auth null_auth;
  19static struct rpc_cred null_cred;
  20
  21static struct rpc_auth *
  22nul_create(const struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
  23{
  24        refcount_inc(&null_auth.au_count);
  25        return &null_auth;
  26}
  27
  28static void
  29nul_destroy(struct rpc_auth *auth)
  30{
  31}
  32
  33/*
  34 * Lookup NULL creds for current process
  35 */
  36static struct rpc_cred *
  37nul_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
  38{
  39        return get_rpccred(&null_cred);
  40}
  41
  42/*
  43 * Destroy cred handle.
  44 */
  45static void
  46nul_destroy_cred(struct rpc_cred *cred)
  47{
  48}
  49
  50/*
  51 * Match cred handle against current process
  52 */
  53static int
  54nul_match(struct auth_cred *acred, struct rpc_cred *cred, int taskflags)
  55{
  56        return 1;
  57}
  58
  59/*
  60 * Marshal credential.
  61 */
  62static int
  63nul_marshal(struct rpc_task *task, struct xdr_stream *xdr)
  64{
  65        __be32 *p;
  66
  67        p = xdr_reserve_space(xdr, 4 * sizeof(*p));
  68        if (!p)
  69                return -EMSGSIZE;
  70        /* Credential */
  71        *p++ = rpc_auth_null;
  72        *p++ = xdr_zero;
  73        /* Verifier */
  74        *p++ = rpc_auth_null;
  75        *p   = xdr_zero;
  76        return 0;
  77}
  78
  79/*
  80 * Refresh credential. This is a no-op for AUTH_NULL
  81 */
  82static int
  83nul_refresh(struct rpc_task *task)
  84{
  85        set_bit(RPCAUTH_CRED_UPTODATE, &task->tk_rqstp->rq_cred->cr_flags);
  86        return 0;
  87}
  88
  89static int
  90nul_validate(struct rpc_task *task, struct xdr_stream *xdr)
  91{
  92        __be32 *p;
  93
  94        p = xdr_inline_decode(xdr, 2 * sizeof(*p));
  95        if (!p)
  96                return -EIO;
  97        if (*p++ != rpc_auth_null)
  98                return -EIO;
  99        if (*p != xdr_zero)
 100                return -EIO;
 101        return 0;
 102}
 103
 104const struct rpc_authops authnull_ops = {
 105        .owner          = THIS_MODULE,
 106        .au_flavor      = RPC_AUTH_NULL,
 107        .au_name        = "NULL",
 108        .create         = nul_create,
 109        .destroy        = nul_destroy,
 110        .lookup_cred    = nul_lookup_cred,
 111};
 112
 113static
 114struct rpc_auth null_auth = {
 115        .au_cslack      = NUL_CALLSLACK,
 116        .au_rslack      = NUL_REPLYSLACK,
 117        .au_verfsize    = NUL_REPLYSLACK,
 118        .au_ralign      = NUL_REPLYSLACK,
 119        .au_ops         = &authnull_ops,
 120        .au_flavor      = RPC_AUTH_NULL,
 121        .au_count       = REFCOUNT_INIT(1),
 122};
 123
 124static
 125const struct rpc_credops null_credops = {
 126        .cr_name        = "AUTH_NULL",
 127        .crdestroy      = nul_destroy_cred,
 128        .crmatch        = nul_match,
 129        .crmarshal      = nul_marshal,
 130        .crwrap_req     = rpcauth_wrap_req_encode,
 131        .crrefresh      = nul_refresh,
 132        .crvalidate     = nul_validate,
 133        .crunwrap_resp  = rpcauth_unwrap_resp_decode,
 134};
 135
 136static
 137struct rpc_cred null_cred = {
 138        .cr_lru         = LIST_HEAD_INIT(null_cred.cr_lru),
 139        .cr_auth        = &null_auth,
 140        .cr_ops         = &null_credops,
 141        .cr_count       = REFCOUNT_INIT(2),
 142        .cr_flags       = 1UL << RPCAUTH_CRED_UPTODATE,
 143};
 144