net/sunrpc/auth_generic.c

   1 /*
   2  * Generic RPC credential
   3  *
   4  * Copyright (C) 2008, Trond Myklebust <Trond.Myklebust@netapp.com>
   5  */
   6
   7 #include <linux/err.h>
   8 #include <linux/types.h>
   9 #include <linux/module.h>
  10 #include <linux/sched.h>
  11 #include <linux/sunrpc/auth.h>
  12 #include <linux/sunrpc/clnt.h>
  13 #include <linux/sunrpc/debug.h>
  14 #include <linux/sunrpc/sched.h>
  15
  16 #ifdef RPC_DEBUG
  17 # define RPCDBG_FACILITY        RPCDBG_AUTH
  18 #endif
  19
  20 struct generic_cred {
  21         struct rpc_cred gc_base;
  22         struct auth_cred acred;
  23 };
  24
  25 static struct rpc_auth generic_auth;
  26 static struct rpc_cred_cache generic_cred_cache;
  27 static const struct rpc_credops generic_credops;
  28
  29 /*
  30  * Public call interface
  31  */
  32 struct rpc_cred *rpc_lookup_cred(void)
  33 {
  34         return rpcauth_lookupcred(&generic_auth, 0);
  35 }
  36 EXPORT_SYMBOL_GPL(rpc_lookup_cred);
  37
  38 static void
  39 generic_bind_cred(struct rpc_task *task, struct rpc_cred *cred)
  40 {
  41         struct rpc_auth *auth = task->tk_client->cl_auth;
  42         struct auth_cred *acred = &container_of(cred, struct generic_cred, gc_base)->acred;
  43         struct rpc_cred *ret;
  44
  45         ret = auth->au_ops->lookup_cred(auth, acred, 0);
  46         if (!IS_ERR(ret))
  47                 task->tk_msg.rpc_cred = ret;
  48         else
  49                 task->tk_status = PTR_ERR(ret);
  50 }
  51
  52 /*
  53  * Lookup generic creds for current process
  54  */
  55 static struct rpc_cred *
  56 generic_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
  57 {
  58         return rpcauth_lookup_credcache(&generic_auth, acred, flags);
  59 }
  60
  61 static struct rpc_cred *
  62 generic_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
  63 {
  64         struct generic_cred *gcred;
  65
  66         gcred = kmalloc(sizeof(*gcred), GFP_KERNEL);
  67         if (gcred == NULL)
  68                 return ERR_PTR(-ENOMEM);
  69
  70         rpcauth_init_cred(&gcred->gc_base, acred, &generic_auth, &generic_credops);
  71         gcred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_UPTODATE;
  72
  73         gcred->acred.uid = acred->uid;
  74         gcred->acred.gid = acred->gid;
  75         gcred->acred.group_info = acred->group_info;
  76         if (gcred->acred.group_info != NULL)
  77                 get_group_info(gcred->acred.group_info);
  78
  79         dprintk("RPC:       allocated generic cred %p for uid %d gid %d\n",
  80                         gcred, acred->uid, acred->gid);
  81         return &gcred->gc_base;
  82 }
  83
  84 static void
  85 generic_free_cred(struct rpc_cred *cred)
  86 {
  87         struct generic_cred *gcred = container_of(cred, struct generic_cred, gc_base);
  88
  89         dprintk("RPC:       generic_free_cred %p\n", gcred);
  90         if (gcred->acred.group_info != NULL)
  91                 put_group_info(gcred->acred.group_info);
  92         kfree(gcred);
  93 }
  94
  95 static void
  96 generic_free_cred_callback(struct rcu_head *head)
  97 {
  98         struct rpc_cred *cred = container_of(head, struct rpc_cred, cr_rcu);
  99         generic_free_cred(cred);
 100 }
 101
 102 static void
 103 generic_destroy_cred(struct rpc_cred *cred)
 104 {
 105         call_rcu(&cred->cr_rcu, generic_free_cred_callback);
 106 }
 107
 108 /*
 109  * Match credentials against current process creds.
 110  */
 111 static int
 112 generic_match(struct auth_cred *acred, struct rpc_cred *cred, int flags)
 113 {
 114         struct generic_cred *gcred = container_of(cred, struct generic_cred, gc_base);
 115
 116         if (gcred->acred.uid != acred->uid ||
 117             gcred->acred.gid != acred->gid ||
 118             gcred->acred.group_info != acred->group_info)
 119                 return 0;
 120         return 1;
 121 }
 122
 123 void __init rpc_init_generic_auth(void)
 124 {
 125         spin_lock_init(&generic_cred_cache.lock);
 126 }
 127
 128 void __exit rpc_destroy_generic_auth(void)
 129 {
 130         rpcauth_clear_credcache(&generic_cred_cache);
 131 }
 132
 133 static struct rpc_cred_cache generic_cred_cache = {
 134         {{ NULL, },},
 135 };
 136
 137 static const struct rpc_authops generic_auth_ops = {
 138         .owner = THIS_MODULE,
 139         .au_name = "Generic",
 140         .lookup_cred = generic_lookup_cred,
 141         .crcreate = generic_create_cred,
 142 };
 143
 144 static struct rpc_auth generic_auth = {
 145         .au_ops = &generic_auth_ops,
 146         .au_count = ATOMIC_INIT(0),
 147         .au_credcache = &generic_cred_cache,
 148 };
 149
 150 static const struct rpc_credops generic_credops = {
 151         .cr_name = "Generic cred",
 152         .crdestroy = generic_destroy_cred,
 153         .crbind = generic_bind_cred,
 154         .crmatch = generic_match,
 155 };