1/* 2 * linux/net/sunrpc/svcauth.c 3 * 4 * The generic interface for RPC authentication on the server side. 5 * 6 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> 7 * 8 * CHANGES 9 * 19-Apr-2000 Chris Evans - Security fix 10 */ 11 12#include <linux/types.h> 13#include <linux/module.h> 14#include <linux/sunrpc/types.h> 15#include <linux/sunrpc/xdr.h> 16#include <linux/sunrpc/svcsock.h> 17#include <linux/sunrpc/svcauth.h> 18#include <linux/err.h> 19#include <linux/hash.h> 20 21#define RPCDBG_FACILITY RPCDBG_AUTH 22 23 24/* 25 * Table of authenticators 26 */ 27extern struct auth_ops svcauth_null; 28extern struct auth_ops svcauth_unix; 29 30static DEFINE_SPINLOCK(authtab_lock); 31static struct auth_ops *authtab[RPC_AUTH_MAXFLAVOR] = { 32 [0] = &svcauth_null, 33 [1] = &svcauth_unix, 34}; 35 36int 37svc_authenticate(struct svc_rqst *rqstp, __be32 *authp) 38{ 39 rpc_authflavor_t flavor; 40 struct auth_ops *aops; 41 42 *authp = rpc_auth_ok; 43 44 flavor = svc_getnl(&rqstp->rq_arg.head[0]); 45 46 dprintk("svc: svc_authenticate (%d)\n", flavor); 47 48 spin_lock(&authtab_lock); 49 if (flavor >= RPC_AUTH_MAXFLAVOR || !(aops = authtab[flavor]) || 50 !try_module_get(aops->owner)) { 51 spin_unlock(&authtab_lock); 52 *authp = rpc_autherr_badcred; 53 return SVC_DENIED; 54 } 55 spin_unlock(&authtab_lock); 56 57 rqstp->rq_authop = aops; 58 return aops->accept(rqstp, authp); 59} 60EXPORT_SYMBOL_GPL(svc_authenticate); 61 62int svc_set_client(struct svc_rqst *rqstp) 63{ 64 return rqstp->rq_authop->set_client(rqstp); 65} 66EXPORT_SYMBOL_GPL(svc_set_client); 67 68/* A request, which was authenticated, has now executed. 69 * Time to finalise the credentials and verifier 70 * and release and resources 71 */ 72int svc_authorise(struct svc_rqst *rqstp) 73{ 74 struct auth_ops *aops = rqstp->rq_authop; 75 int rv = 0; 76 77 rqstp->rq_authop = NULL; 78 79 if (aops) { 80 rv = aops->release(rqstp); 81 module_put(aops->owner); 82 } 83 return rv; 84} 85 86int 87svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops) 88{ 89 int rv = -EINVAL; 90 spin_lock(&authtab_lock); 91 if (flavor < RPC_AUTH_MAXFLAVOR && authtab[flavor] == NULL) { 92 authtab[flavor] = aops; 93 rv = 0; 94 } 95 spin_unlock(&authtab_lock); 96 return rv; 97} 98EXPORT_SYMBOL_GPL(svc_auth_register); 99 100void 101svc_auth_unregister(rpc_authflavor_t flavor) 102{ 103 spin_lock(&authtab_lock); 104 if (flavor < RPC_AUTH_MAXFLAVOR) 105 authtab[flavor] = NULL; 106 spin_unlock(&authtab_lock); 107} 108EXPORT_SYMBOL_GPL(svc_auth_unregister); 109 110/************************************************** 111 * 'auth_domains' are stored in a hash table indexed by name. 112 * When the last reference to an 'auth_domain' is dropped, 113 * the object is unhashed and freed. 114 * If auth_domain_lookup fails to find an entry, it will return 115 * it's second argument 'new'. If this is non-null, it will 116 * have been atomically linked into the table. 117 */ 118 119#define DN_HASHBITS 6 120#define DN_HASHMAX (1<<DN_HASHBITS) 121#define DN_HASHMASK (DN_HASHMAX-1) 122 123static struct hlist_head auth_domain_table[DN_HASHMAX]; 124static spinlock_t auth_domain_lock = 125 __SPIN_LOCK_UNLOCKED(auth_domain_lock); 126 127void auth_domain_put(struct auth_domain *dom) 128{ 129 if (atomic_dec_and_lock(&dom->ref.refcount, &auth_domain_lock)) { 130 hlist_del(&dom->hash); 131 dom->flavour->domain_release(dom); 132 spin_unlock(&auth_domain_lock); 133 } 134} 135EXPORT_SYMBOL_GPL(auth_domain_put); 136 137struct auth_domain * 138auth_domain_lookup(char *name, struct auth_domain *new) 139{ 140 struct auth_domain *hp; 141 struct hlist_head *head; 142 struct hlist_node *np; 143 144 head = &auth_domain_table[hash_str(name, DN_HASHBITS)]; 145 146 spin_lock(&auth_domain_lock); 147 148 hlist_for_each_entry(hp, np, head, hash) { 149 if (strcmp(hp->name, name)==0) { 150 kref_get(&hp->ref); 151 spin_unlock(&auth_domain_lock); 152 return hp; 153 } 154 } 155 if (new) 156 hlist_add_head(&new->hash, head); 157 spin_unlock(&auth_domain_lock); 158 return new; 159} 160EXPORT_SYMBOL_GPL(auth_domain_lookup); 161 162struct auth_domain *auth_domain_find(char *name) 163{ 164 return auth_domain_lookup(name, NULL); 165} 166EXPORT_SYMBOL_GPL(auth_domain_find); 167