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(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 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 return get_rpccred(&null_cred); 40 } 41 42 /* 43 * Destroy cred handle. 44 */ 45 static void 46 nul_destroy_cred(struct rpc_cred *cred) 47 { 48 } 49 50 /* 51 * Match cred handle against current process 52 */ 53 static int 54 nul_match(struct auth_cred *acred, struct rpc_cred *cred, int taskflags) 55 { 56 return 1; 57 } 58 59 /* 60 * Marshal credential. 61 */ 62 static int 63 nul_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 */ 82 static int 83 nul_refresh(struct rpc_task *task) 84 { 85 set_bit(RPCAUTH_CRED_UPTODATE, &task->tk_rqstp->rq_cred->cr_flags); 86 return 0; 87 } 88 89 static int 90 nul_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 } 103 104 const 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 }; 112 113 static 114 struct 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 }; 123 124 static 125 const 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 }; 135 136 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 = REFCOUNT_INIT(2), 142 .cr_flags = 1UL << RPCAUTH_CRED_UPTODATE, 143 }; 144