123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234 |
- // SPDX-License-Identifier: GPL-2.0-only
- /*
- * linux/net/sunrpc/svcauth.c
- *
- * The generic interface for RPC authentication on the server side.
- *
- * Copyright (C) 1995, 1996 Olaf Kirch <[email protected]>
- *
- * CHANGES
- * 19-Apr-2000 Chris Evans - Security fix
- */
- #include <linux/types.h>
- #include <linux/module.h>
- #include <linux/sunrpc/types.h>
- #include <linux/sunrpc/xdr.h>
- #include <linux/sunrpc/svcsock.h>
- #include <linux/sunrpc/svcauth.h>
- #include <linux/err.h>
- #include <linux/hash.h>
- #include <trace/events/sunrpc.h>
- #include "sunrpc.h"
- #define RPCDBG_FACILITY RPCDBG_AUTH
- /*
- * Table of authenticators
- */
- extern struct auth_ops svcauth_null;
- extern struct auth_ops svcauth_unix;
- extern struct auth_ops svcauth_tls;
- static struct auth_ops __rcu *authtab[RPC_AUTH_MAXFLAVOR] = {
- [RPC_AUTH_NULL] = (struct auth_ops __force __rcu *)&svcauth_null,
- [RPC_AUTH_UNIX] = (struct auth_ops __force __rcu *)&svcauth_unix,
- [RPC_AUTH_TLS] = (struct auth_ops __force __rcu *)&svcauth_tls,
- };
- static struct auth_ops *
- svc_get_auth_ops(rpc_authflavor_t flavor)
- {
- struct auth_ops *aops;
- if (flavor >= RPC_AUTH_MAXFLAVOR)
- return NULL;
- rcu_read_lock();
- aops = rcu_dereference(authtab[flavor]);
- if (aops != NULL && !try_module_get(aops->owner))
- aops = NULL;
- rcu_read_unlock();
- return aops;
- }
- static void
- svc_put_auth_ops(struct auth_ops *aops)
- {
- module_put(aops->owner);
- }
- int
- svc_authenticate(struct svc_rqst *rqstp)
- {
- rpc_authflavor_t flavor;
- struct auth_ops *aops;
- rqstp->rq_auth_stat = rpc_auth_ok;
- flavor = svc_getnl(&rqstp->rq_arg.head[0]);
- dprintk("svc: svc_authenticate (%d)\n", flavor);
- aops = svc_get_auth_ops(flavor);
- if (aops == NULL) {
- rqstp->rq_auth_stat = rpc_autherr_badcred;
- return SVC_DENIED;
- }
- rqstp->rq_auth_slack = 0;
- init_svc_cred(&rqstp->rq_cred);
- rqstp->rq_authop = aops;
- return aops->accept(rqstp);
- }
- EXPORT_SYMBOL_GPL(svc_authenticate);
- int svc_set_client(struct svc_rqst *rqstp)
- {
- rqstp->rq_client = NULL;
- return rqstp->rq_authop->set_client(rqstp);
- }
- EXPORT_SYMBOL_GPL(svc_set_client);
- /* A request, which was authenticated, has now executed.
- * Time to finalise the credentials and verifier
- * and release and resources
- */
- int svc_authorise(struct svc_rqst *rqstp)
- {
- struct auth_ops *aops = rqstp->rq_authop;
- int rv = 0;
- rqstp->rq_authop = NULL;
- if (aops) {
- rv = aops->release(rqstp);
- svc_put_auth_ops(aops);
- }
- return rv;
- }
- int
- svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops)
- {
- struct auth_ops *old;
- int rv = -EINVAL;
- if (flavor < RPC_AUTH_MAXFLAVOR) {
- old = cmpxchg((struct auth_ops ** __force)&authtab[flavor], NULL, aops);
- if (old == NULL || old == aops)
- rv = 0;
- }
- return rv;
- }
- EXPORT_SYMBOL_GPL(svc_auth_register);
- void
- svc_auth_unregister(rpc_authflavor_t flavor)
- {
- if (flavor < RPC_AUTH_MAXFLAVOR)
- rcu_assign_pointer(authtab[flavor], NULL);
- }
- EXPORT_SYMBOL_GPL(svc_auth_unregister);
- /**************************************************
- * 'auth_domains' are stored in a hash table indexed by name.
- * When the last reference to an 'auth_domain' is dropped,
- * the object is unhashed and freed.
- * If auth_domain_lookup fails to find an entry, it will return
- * it's second argument 'new'. If this is non-null, it will
- * have been atomically linked into the table.
- */
- #define DN_HASHBITS 6
- #define DN_HASHMAX (1<<DN_HASHBITS)
- static struct hlist_head auth_domain_table[DN_HASHMAX];
- static DEFINE_SPINLOCK(auth_domain_lock);
- static void auth_domain_release(struct kref *kref)
- __releases(&auth_domain_lock)
- {
- struct auth_domain *dom = container_of(kref, struct auth_domain, ref);
- hlist_del_rcu(&dom->hash);
- dom->flavour->domain_release(dom);
- spin_unlock(&auth_domain_lock);
- }
- void auth_domain_put(struct auth_domain *dom)
- {
- kref_put_lock(&dom->ref, auth_domain_release, &auth_domain_lock);
- }
- EXPORT_SYMBOL_GPL(auth_domain_put);
- struct auth_domain *
- auth_domain_lookup(char *name, struct auth_domain *new)
- {
- struct auth_domain *hp;
- struct hlist_head *head;
- head = &auth_domain_table[hash_str(name, DN_HASHBITS)];
- spin_lock(&auth_domain_lock);
- hlist_for_each_entry(hp, head, hash) {
- if (strcmp(hp->name, name)==0) {
- kref_get(&hp->ref);
- spin_unlock(&auth_domain_lock);
- return hp;
- }
- }
- if (new)
- hlist_add_head_rcu(&new->hash, head);
- spin_unlock(&auth_domain_lock);
- return new;
- }
- EXPORT_SYMBOL_GPL(auth_domain_lookup);
- struct auth_domain *auth_domain_find(char *name)
- {
- struct auth_domain *hp;
- struct hlist_head *head;
- head = &auth_domain_table[hash_str(name, DN_HASHBITS)];
- rcu_read_lock();
- hlist_for_each_entry_rcu(hp, head, hash) {
- if (strcmp(hp->name, name)==0) {
- if (!kref_get_unless_zero(&hp->ref))
- hp = NULL;
- rcu_read_unlock();
- return hp;
- }
- }
- rcu_read_unlock();
- return NULL;
- }
- EXPORT_SYMBOL_GPL(auth_domain_find);
- /**
- * auth_domain_cleanup - check that the auth_domain table is empty
- *
- * On module unload the auth_domain_table must be empty. To make it
- * easier to catch bugs which don't clean up domains properly, we
- * warn if anything remains in the table at cleanup time.
- *
- * Note that we cannot proactively remove the domains at this stage.
- * The ->release() function might be in a module that has already been
- * unloaded.
- */
- void auth_domain_cleanup(void)
- {
- int h;
- struct auth_domain *hp;
- for (h = 0; h < DN_HASHMAX; h++)
- hlist_for_each_entry(hp, &auth_domain_table[h], hash)
- pr_warn("svc: domain %s still present at module unload.\n",
- hp->name);
- }
|