net/sunrpc/auth_null.c

   1 /*
   2  * linux/net/sunrpc/auth_null.c
   3  *
   4  * AUTH_NULL authentication. Really :-)
   5  *
   6  * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
   7  */
   8
   9 #include <linux/types.h>
  10 #include <linux/module.h>
  11 #include <linux/sunrpc/clnt.h>
  12
  13 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
  14 # define RPCDBG_FACILITY        RPCDBG_AUTH
  15 #endif
  16
  17 static struct rpc_auth null_auth;
  18 static struct rpc_cred null_cred;
  19
  20 static struct rpc_auth *
  21 nul_create(struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
  22 {
  23         atomic_inc(&null_auth.au_count);
  24         return &null_auth;
  25 }
  26
  27 static void
  28 nul_destroy(struct rpc_auth *auth)
  29 {
  30 }
  31
  32 /*
  33  * Lookup NULL creds for current process
  34  */
  35 static struct rpc_cred *
  36 nul_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
  37 {
  38         if (flags & RPCAUTH_LOOKUP_RCU)
  39                 return &null_cred;
  40         return get_rpccred(&null_cred);
  41 }
  42
  43 /*
  44  * Destroy cred handle.
  45  */
  46 static void
  47 nul_destroy_cred(struct rpc_cred *cred)
  48 {
  49 }
  50
  51 /*
  52  * Match cred handle against current process
  53  */
  54 static int
  55 nul_match(struct auth_cred *acred, struct rpc_cred *cred, int taskflags)
  56 {
  57         return 1;
  58 }
  59
  60 /*
  61  * Marshal credential.
  62  */
  63 static __be32 *
  64 nul_marshal(struct rpc_task *task, __be32 *p)
  65 {
  66         *p++ = htonl(RPC_AUTH_NULL);
  67         *p++ = 0;
  68         *p++ = htonl(RPC_AUTH_NULL);
  69         *p++ = 0;
  70
  71         return p;
  72 }
  73
  74 /*
  75  * Refresh credential. This is a no-op for AUTH_NULL
  76  */
  77 static int
  78 nul_refresh(struct rpc_task *task)
  79 {
  80         set_bit(RPCAUTH_CRED_UPTODATE, &task->tk_rqstp->rq_cred->cr_flags);
  81         return 0;
  82 }
  83
  84 static __be32 *
  85 nul_validate(struct rpc_task *task, __be32 *p)
  86 {
  87         rpc_authflavor_t        flavor;
  88         u32                     size;
  89
  90         flavor = ntohl(*p++);
  91         if (flavor != RPC_AUTH_NULL) {
  92                 printk("RPC: bad verf flavor: %u\n", flavor);
  93                 return ERR_PTR(-EIO);
  94         }
  95
  96         size = ntohl(*p++);
  97         if (size != 0) {
  98                 printk("RPC: bad verf size: %u\n", size);
  99                 return ERR_PTR(-EIO);
 100         }
 101
 102         return p;
 103 }
 104
 105 const struct rpc_authops authnull_ops = {
 106         .owner          = THIS_MODULE,
 107         .au_flavor      = RPC_AUTH_NULL,
 108         .au_name        = "NULL",
 109         .create         = nul_create,
 110         .destroy        = nul_destroy,
 111         .lookup_cred    = nul_lookup_cred,
 112 };
 113
 114 static
 115 struct rpc_auth null_auth = {
 116         .au_cslack      = 4,
 117         .au_rslack      = 2,
 118         .au_ops         = &authnull_ops,
 119         .au_flavor      = RPC_AUTH_NULL,
 120         .au_count       = ATOMIC_INIT(0),
 121 };
 122
 123 static
 124 const struct rpc_credops null_credops = {
 125         .cr_name        = "AUTH_NULL",
 126         .crdestroy      = nul_destroy_cred,
 127         .crbind         = rpcauth_generic_bind_cred,
 128         .crmatch        = nul_match,
 129         .crmarshal      = nul_marshal,
 130         .crrefresh      = nul_refresh,
 131         .crvalidate     = nul_validate,
 132 };
 133
 134 static
 135 struct rpc_cred null_cred = {
 136         .cr_lru         = LIST_HEAD_INIT(null_cred.cr_lru),
 137         .cr_auth        = &null_auth,
 138         .cr_ops         = &null_credops,
 139         .cr_count       = ATOMIC_INIT(1),
 140         .cr_flags       = 1UL << RPCAUTH_CRED_UPTODATE,
 141 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 142         .cr_magic       = RPCAUTH_CRED_MAGIC,
 143 #endif
 144 };