net/sunrpc/auth_null.c

   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
  18 static struct rpc_auth null_auth;
  19 static struct rpc_cred null_cred;
  20
  21 static struct rpc_auth *
  22 nul_create(struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
  23 {
  24         atomic_inc(&null_auth.au_count);
  25         return &null_auth;
  26 }
  27
  28 static void
  29 nul_destroy(struct rpc_auth *auth)
  30 {
  31 }
  32
  33 /*
  34  * Lookup NULL creds for current process
  35  */
  36 static struct rpc_cred *
  37 nul_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
  38 {
  39         if (flags & RPCAUTH_LOOKUP_RCU)
  40                 return &null_cred;
  41         return get_rpccred(&null_cred);
  42 }
  43
  44 /*
  45  * Destroy cred handle.
  46  */
  47 static void
  48 nul_destroy_cred(struct rpc_cred *cred)
  49 {
  50 }
  51
  52 /*
  53  * Match cred handle against current process
  54  */
  55 static int
  56 nul_match(struct auth_cred *acred, struct rpc_cred *cred, int taskflags)
  57 {
  58         return 1;
  59 }
  60
  61 /*
  62  * Marshal credential.
  63  */
  64 static __be32 *
  65 nul_marshal(struct rpc_task *task, __be32 *p)
  66 {
  67         *p++ = htonl(RPC_AUTH_NULL);
  68         *p++ = 0;
  69         *p++ = htonl(RPC_AUTH_NULL);
  70         *p++ = 0;
  71
  72         return p;
  73 }
  74
  75 /*
  76  * Refresh credential. This is a no-op for AUTH_NULL
  77  */
  78 static int
  79 nul_refresh(struct rpc_task *task)
  80 {
  81         set_bit(RPCAUTH_CRED_UPTODATE, &task->tk_rqstp->rq_cred->cr_flags);
  82         return 0;
  83 }
  84
  85 static __be32 *
  86 nul_validate(struct rpc_task *task, __be32 *p)
  87 {
  88         rpc_authflavor_t        flavor;
  89         u32                     size;
  90
  91         flavor = ntohl(*p++);
  92         if (flavor != RPC_AUTH_NULL) {
  93                 printk("RPC: bad verf flavor: %u\n", flavor);
  94                 return ERR_PTR(-EIO);
  95         }
  96
  97         size = ntohl(*p++);
  98         if (size != 0) {
  99                 printk("RPC: bad verf size: %u\n", size);
 100                 return ERR_PTR(-EIO);
 101         }
 102
 103         return p;
 104 }
 105
 106 const struct rpc_authops authnull_ops = {
 107         .owner          = THIS_MODULE,
 108         .au_flavor      = RPC_AUTH_NULL,
 109         .au_name        = "NULL",
 110         .create         = nul_create,
 111         .destroy        = nul_destroy,
 112         .lookup_cred    = nul_lookup_cred,
 113 };
 114
 115 static
 116 struct rpc_auth null_auth = {
 117         .au_cslack      = NUL_CALLSLACK,
 118         .au_rslack      = NUL_REPLYSLACK,
 119         .au_flags       = RPCAUTH_AUTH_NO_CRKEY_TIMEOUT,
 120         .au_ops         = &authnull_ops,
 121         .au_flavor      = RPC_AUTH_NULL,
 122         .au_count       = ATOMIC_INIT(0),
 123 };
 124
 125 static
 126 const struct rpc_credops null_credops = {
 127         .cr_name        = "AUTH_NULL",
 128         .crdestroy      = nul_destroy_cred,
 129         .crbind         = rpcauth_generic_bind_cred,
 130         .crmatch        = nul_match,
 131         .crmarshal      = nul_marshal,
 132         .crrefresh      = nul_refresh,
 133         .crvalidate     = nul_validate,
 134 };
 135
 136 static
 137 struct 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       = ATOMIC_INIT(1),
 142         .cr_flags       = 1UL << RPCAUTH_CRED_UPTODATE,
 143 };