[mirror_ubuntu-bionic-kernel.git] / net / sunrpc / svcauth.c

/*
 * linux/net/sunrpc/svcauth.c
 *
 * The generic interface for RPC authentication on the server side.
 *
 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
 *
 * 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>

#define RPCDBG_FACILITY	RPCDBG_AUTH


/*
 * Table of authenticators
 */
extern struct auth_ops svcauth_null;
extern struct auth_ops svcauth_unix;

static DEFINE_SPINLOCK(authtab_lock);
static struct auth_ops	*authtab[RPC_AUTH_MAXFLAVOR] = {
	[0] = &svcauth_null,
	[1] = &svcauth_unix,
};

int
svc_authenticate(struct svc_rqst *rqstp, __be32 *authp)
{
	rpc_authflavor_t	flavor;
	struct auth_ops		*aops;

	*authp = rpc_auth_ok;

	flavor = svc_getnl(&rqstp->rq_arg.head[0]);

	dprintk("svc: svc_authenticate (%d)\n", flavor);

	spin_lock(&authtab_lock);
	if (flavor >= RPC_AUTH_MAXFLAVOR || !(aops = authtab[flavor]) ||
	    !try_module_get(aops->owner)) {
		spin_unlock(&authtab_lock);
		*authp = rpc_autherr_badcred;
		return SVC_DENIED;
	}
	spin_unlock(&authtab_lock);

	rqstp->rq_auth_slack = 0;
	init_svc_cred(&rqstp->rq_cred);

	rqstp->rq_authop = aops;
	return aops->accept(rqstp, authp);
}
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);
		module_put(aops->owner);
	}
	return rv;
}

int
svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops)
{
	int rv = -EINVAL;
	spin_lock(&authtab_lock);
	if (flavor < RPC_AUTH_MAXFLAVOR && authtab[flavor] == NULL) {
		authtab[flavor] = aops;
		rv = 0;
	}
	spin_unlock(&authtab_lock);
	return rv;
}
EXPORT_SYMBOL_GPL(svc_auth_register);

void
svc_auth_unregister(rpc_authflavor_t flavor)
{
	spin_lock(&authtab_lock);
	if (flavor < RPC_AUTH_MAXFLAVOR)
		authtab[flavor] = NULL;
	spin_unlock(&authtab_lock);
}
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)
{
	struct auth_domain *dom = container_of(kref, struct auth_domain, ref);

	hlist_del(&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(&new->hash, head);
	spin_unlock(&auth_domain_lock);
	return new;
}
EXPORT_SYMBOL_GPL(auth_domain_lookup);

struct auth_domain *auth_domain_find(char *name)
{
	return auth_domain_lookup(name, NULL);
}
EXPORT_SYMBOL_GPL(auth_domain_find);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/net/sunrpc/svcauth.c
	3	*
	4	* The generic interface for RPC authentication on the server side.
cca5172a	5	*
1da177e4 LT	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>
1da177e4 LT	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	*/
	27	extern struct auth_ops svcauth_null;
	28	extern struct auth_ops svcauth_unix;
	29
	30	static DEFINE_SPINLOCK(authtab_lock);
	31	static struct auth_ops *authtab[RPC_AUTH_MAXFLAVOR] = {
	32	[0] = &svcauth_null,
	33	[1] = &svcauth_unix,
	34	};
	35
	36	int
d8ed029d	37	svc_authenticate(struct svc_rqst rqstp, __be32 authp)
1da177e4 LT	38	{
	39	rpc_authflavor_t flavor;
	40	struct auth_ops *aops;
	41
	42	*authp = rpc_auth_ok;
	43
76994313	44	flavor = svc_getnl(&rqstp->rq_arg.head[0]);
1da177e4 LT	45
	46	dprintk("svc: svc_authenticate (%d)\n", flavor);
	47
	48	spin_lock(&authtab_lock);
f64f9e71 JP	49	if (flavor >= RPC_AUTH_MAXFLAVOR \|\| !(aops = authtab[flavor]) \|\|
f64f9e71 JP	50	!try_module_get(aops->owner)) {
1da177e4 LT	51	spin_unlock(&authtab_lock);
	52	*authp = rpc_autherr_badcred;
	53	return SVC_DENIED;
	54	}
	55	spin_unlock(&authtab_lock);
	56
a5cddc88	57	rqstp->rq_auth_slack = 0;
6496500c	58	init_svc_cred(&rqstp->rq_cred);
a5cddc88	59
1da177e4 LT	60	rqstp->rq_authop = aops;
	61	return aops->accept(rqstp, authp);
	62	}
24c3767e	63	EXPORT_SYMBOL_GPL(svc_authenticate);
1da177e4 LT	64
	65	int svc_set_client(struct svc_rqst *rqstp)
	66	{
6496500c	67	rqstp->rq_client = NULL;
1da177e4 LT	68	return rqstp->rq_authop->set_client(rqstp);
1da177e4 LT	69	}
24c3767e	70	EXPORT_SYMBOL_GPL(svc_set_client);
1da177e4 LT	71
1da177e4 LT	72	/* A request, which was authenticated, has now executed.
59c51591	73	* Time to finalise the credentials and verifier
1da177e4 LT	74	* and release and resources
	75	*/
	76	int svc_authorise(struct svc_rqst *rqstp)
	77	{
	78	struct auth_ops *aops = rqstp->rq_authop;
	79	int rv = 0;
	80
	81	rqstp->rq_authop = NULL;
cca5172a	82
1da177e4 LT	83	if (aops) {
	84	rv = aops->release(rqstp);
	85	module_put(aops->owner);
	86	}
	87	return rv;
	88	}
	89
	90	int
	91	svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops)
	92	{
	93	int rv = -EINVAL;
	94	spin_lock(&authtab_lock);
	95	if (flavor < RPC_AUTH_MAXFLAVOR && authtab[flavor] == NULL) {
	96	authtab[flavor] = aops;
	97	rv = 0;
	98	}
	99	spin_unlock(&authtab_lock);
	100	return rv;
	101	}
24c3767e	102	EXPORT_SYMBOL_GPL(svc_auth_register);
1da177e4 LT	103
	104	void
	105	svc_auth_unregister(rpc_authflavor_t flavor)
	106	{
	107	spin_lock(&authtab_lock);
	108	if (flavor < RPC_AUTH_MAXFLAVOR)
	109	authtab[flavor] = NULL;
	110	spin_unlock(&authtab_lock);
	111	}
24c3767e	112	EXPORT_SYMBOL_GPL(svc_auth_unregister);
1da177e4 LT	113
1da177e4 LT	114	/**************************************************
efc36aa5 N	115	* 'auth_domains' are stored in a hash table indexed by name.
	116	* When the last reference to an 'auth_domain' is dropped,
	117	* the object is unhashed and freed.
	118	* If auth_domain_lookup fails to find an entry, it will return
	119	* it's second argument 'new'. If this is non-null, it will
	120	* have been atomically linked into the table.
1da177e4 LT	121	*/
1da177e4 LT	122
1da177e4 LT	123	#define DN_HASHBITS 6
1da177e4 LT	124	#define DN_HASHMAX (1<<DN_HASHBITS)
1da177e4	125
efc36aa5	126	static struct hlist_head auth_domain_table[DN_HASHMAX];
3eb15f28	127	static DEFINE_SPINLOCK(auth_domain_lock);
1da177e4	128
0a13cd1a PZ	129	static void auth_domain_release(struct kref *kref)
	130	{
	131	struct auth_domain *dom = container_of(kref, struct auth_domain, ref);
	132
	133	hlist_del(&dom->hash);
	134	dom->flavour->domain_release(dom);
	135	spin_unlock(&auth_domain_lock);
	136	}
	137
1da177e4 LT	138	void auth_domain_put(struct auth_domain *dom)
1da177e4 LT	139	{
0a13cd1a	140	kref_put_lock(&dom->ref, auth_domain_release, &auth_domain_lock);
1da177e4	141	}
24c3767e	142	EXPORT_SYMBOL_GPL(auth_domain_put);
1da177e4 LT	143
1da177e4 LT	144	struct auth_domain *
efc36aa5	145	auth_domain_lookup(char name, struct auth_domain new)
1da177e4	146	{
efc36aa5 N	147	struct auth_domain *hp;
efc36aa5 N	148	struct hlist_head *head;
efc36aa5 N	149
	150	head = &auth_domain_table[hash_str(name, DN_HASHBITS)];
	151
	152	spin_lock(&auth_domain_lock);
	153
b67bfe0d	154	hlist_for_each_entry(hp, head, hash) {
efc36aa5 N	155	if (strcmp(hp->name, name)==0) {
	156	kref_get(&hp->ref);
	157	spin_unlock(&auth_domain_lock);
	158	return hp;
1da177e4	159	}
1da177e4	160	}
d6740df9	161	if (new)
efc36aa5	162	hlist_add_head(&new->hash, head);
efc36aa5 N	163	spin_unlock(&auth_domain_lock);
efc36aa5 N	164	return new;
1da177e4	165	}
24c3767e	166	EXPORT_SYMBOL_GPL(auth_domain_lookup);
1da177e4 LT	167
	168	struct auth_domain auth_domain_find(char name)
	169	{
efc36aa5	170	return auth_domain_lookup(name, NULL);
1da177e4	171	}
24c3767e	172	EXPORT_SYMBOL_GPL(auth_domain_find);