[deliverable/linux.git] / include / linux / sunrpc / auth.h

/*
 * linux/include/linux/sunrpc/auth.h
 *
 * Declarations for the RPC client authentication machinery.
 *
 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
 */

#ifndef _LINUX_SUNRPC_AUTH_H
#define _LINUX_SUNRPC_AUTH_H

#ifdef __KERNEL__

#include <linux/sunrpc/sched.h>
#include <linux/sunrpc/msg_prot.h>
#include <linux/sunrpc/xdr.h>

#include <linux/atomic.h>
#include <linux/rcupdate.h>
#include <linux/uidgid.h>
#include <linux/utsname.h>

/*
 * Maximum size of AUTH_NONE authentication information, in XDR words.
 */
#define NUL_CALLSLACK	(4)
#define NUL_REPLYSLACK	(2)

/*
 * Size of the nodename buffer. RFC1831 specifies a hard limit of 255 bytes,
 * but Linux hostnames are actually limited to __NEW_UTS_LEN bytes.
 */
#define UNX_MAXNODENAME	__NEW_UTS_LEN
#define UNX_CALLSLACK	(21 + XDR_QUADLEN(UNX_MAXNODENAME))

struct rpcsec_gss_info;

/* auth_cred ac_flags bits */
enum {
	RPC_CRED_NO_CRKEY_TIMEOUT = 0, /* underlying cred has no key timeout */
	RPC_CRED_KEY_EXPIRE_SOON = 1, /* underlying cred key will expire soon */
	RPC_CRED_NOTIFY_TIMEOUT = 2,   /* nofity generic cred when underlying
					key will expire soon */
};

/* Work around the lack of a VFS credential */
struct auth_cred {
	kuid_t	uid;
	kgid_t	gid;
	struct group_info *group_info;
	const char *principal;
	unsigned long ac_flags;
	unsigned char machine_cred : 1;
};

/*
 * Client user credentials
 */
struct rpc_auth;
struct rpc_credops;
struct rpc_cred {
	struct hlist_node	cr_hash;	/* hash chain */
	struct list_head	cr_lru;		/* lru garbage collection */
	struct rcu_head		cr_rcu;
	struct rpc_auth *	cr_auth;
	const struct rpc_credops *cr_ops;
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
	unsigned long		cr_magic;	/* 0x0f4aa4f0 */
#endif
	unsigned long		cr_expire;	/* when to gc */
	unsigned long		cr_flags;	/* various flags */
	atomic_t		cr_count;	/* ref count */

	kuid_t			cr_uid;

	/* per-flavor data */
};
#define RPCAUTH_CRED_NEW	0
#define RPCAUTH_CRED_UPTODATE	1
#define RPCAUTH_CRED_HASHED	2
#define RPCAUTH_CRED_NEGATIVE	3

#define RPCAUTH_CRED_MAGIC	0x0f4aa4f0

/*
 * Client authentication handle
 */
struct rpc_cred_cache;
struct rpc_authops;
struct rpc_auth {
	unsigned int		au_cslack;	/* call cred size estimate */
				/* guess at number of u32's auth adds before
				 * reply data; normally the verifier size: */
	unsigned int		au_rslack;
				/* for gss, used to calculate au_rslack: */
	unsigned int		au_verfsize;

	unsigned int		au_flags;	/* various flags */
	const struct rpc_authops *au_ops;		/* operations */
	rpc_authflavor_t	au_flavor;	/* pseudoflavor (note may
						 * differ from the flavor in
						 * au_ops->au_flavor in gss
						 * case) */
	atomic_t		au_count;	/* Reference counter */

	struct rpc_cred_cache *	au_credcache;
	/* per-flavor data */
};

struct rpc_auth_create_args {
	rpc_authflavor_t pseudoflavor;
	const char *target_name;
};

/* Flags for rpcauth_lookupcred() */
#define RPCAUTH_LOOKUP_NEW		0x01	/* Accept an uninitialised cred */
#define RPCAUTH_LOOKUP_RCU		0x02	/* lock-less lookup */

/*
 * Client authentication ops
 */
struct rpc_authops {
	struct module		*owner;
	rpc_authflavor_t	au_flavor;	/* flavor (RPC_AUTH_*) */
	char *			au_name;
	struct rpc_auth *	(*create)(struct rpc_auth_create_args *, struct rpc_clnt *);
	void			(*destroy)(struct rpc_auth *);

	struct rpc_cred *	(*lookup_cred)(struct rpc_auth *, struct auth_cred *, int);
	struct rpc_cred *	(*crcreate)(struct rpc_auth*, struct auth_cred *, int, gfp_t);
	int			(*list_pseudoflavors)(rpc_authflavor_t *, int);
	rpc_authflavor_t	(*info2flavor)(struct rpcsec_gss_info *);
	int			(*flavor2info)(rpc_authflavor_t,
						struct rpcsec_gss_info *);
	int			(*key_timeout)(struct rpc_auth *,
						struct rpc_cred *);
};

struct rpc_credops {
	const char *		cr_name;	/* Name of the auth flavour */
	int			(*cr_init)(struct rpc_auth *, struct rpc_cred *);
	void			(*crdestroy)(struct rpc_cred *);

	int			(*crmatch)(struct auth_cred *, struct rpc_cred *, int);
	struct rpc_cred *	(*crbind)(struct rpc_task *, struct rpc_cred *, int);
	__be32 *		(*crmarshal)(struct rpc_task *, __be32 *);
	int			(*crrefresh)(struct rpc_task *);
	__be32 *		(*crvalidate)(struct rpc_task *, __be32 *);
	int			(*crwrap_req)(struct rpc_task *, kxdreproc_t,
						void *, __be32 *, void *);
	int			(*crunwrap_resp)(struct rpc_task *, kxdrdproc_t,
						void *, __be32 *, void *);
	int			(*crkey_timeout)(struct rpc_cred *);
	bool			(*crkey_to_expire)(struct rpc_cred *);
	char *			(*crstringify_acceptor)(struct rpc_cred *);
};

extern const struct rpc_authops	authunix_ops;
extern const struct rpc_authops	authnull_ops;

int __init		rpc_init_authunix(void);
int __init		rpc_init_generic_auth(void);
int __init		rpcauth_init_module(void);
void			rpcauth_remove_module(void);
void			rpc_destroy_generic_auth(void);
void 			rpc_destroy_authunix(void);

struct rpc_cred *	rpc_lookup_cred(void);
struct rpc_cred *	rpc_lookup_cred_nonblock(void);
struct rpc_cred *	rpc_lookup_generic_cred(struct auth_cred *, int, gfp_t);
struct rpc_cred *	rpc_lookup_machine_cred(const char *service_name);
int			rpcauth_register(const struct rpc_authops *);
int			rpcauth_unregister(const struct rpc_authops *);
struct rpc_auth *	rpcauth_create(struct rpc_auth_create_args *,
				struct rpc_clnt *);
void			rpcauth_release(struct rpc_auth *);
rpc_authflavor_t	rpcauth_get_pseudoflavor(rpc_authflavor_t,
				struct rpcsec_gss_info *);
int			rpcauth_get_gssinfo(rpc_authflavor_t,
				struct rpcsec_gss_info *);
int			rpcauth_list_flavors(rpc_authflavor_t *, int);
struct rpc_cred *	rpcauth_lookup_credcache(struct rpc_auth *, struct auth_cred *, int, gfp_t);
void			rpcauth_init_cred(struct rpc_cred *, const struct auth_cred *, struct rpc_auth *, const struct rpc_credops *);
struct rpc_cred *	rpcauth_lookupcred(struct rpc_auth *, int);
struct rpc_cred *	rpcauth_generic_bind_cred(struct rpc_task *, struct rpc_cred *, int);
void			put_rpccred(struct rpc_cred *);
__be32 *		rpcauth_marshcred(struct rpc_task *, __be32 *);
__be32 *		rpcauth_checkverf(struct rpc_task *, __be32 *);
int			rpcauth_wrap_req(struct rpc_task *task, kxdreproc_t encode, void *rqstp, __be32 *data, void *obj);
int			rpcauth_unwrap_resp(struct rpc_task *task, kxdrdproc_t decode, void *rqstp, __be32 *data, void *obj);
int			rpcauth_refreshcred(struct rpc_task *);
void			rpcauth_invalcred(struct rpc_task *);
int			rpcauth_uptodatecred(struct rpc_task *);
int			rpcauth_init_credcache(struct rpc_auth *);
void			rpcauth_destroy_credcache(struct rpc_auth *);
void			rpcauth_clear_credcache(struct rpc_cred_cache *);
int			rpcauth_key_timeout_notify(struct rpc_auth *,
						struct rpc_cred *);
bool			rpcauth_cred_key_to_expire(struct rpc_cred *);
char *			rpcauth_stringify_acceptor(struct rpc_cred *);

static inline
struct rpc_cred *	get_rpccred(struct rpc_cred *cred)
{
	if (cred != NULL)
		atomic_inc(&cred->cr_count);
	return cred;
}

/**
 * get_rpccred_rcu - get a reference to a cred using rcu-protected pointer
 * @cred: cred of which to take a reference
 *
 * In some cases, we may have a pointer to a credential to which we
 * want to take a reference, but don't already have one. Because these
 * objects are freed using RCU, we can access the cr_count while its
 * on its way to destruction and only take a reference if it's not already
 * zero.
 */
static inline struct rpc_cred *
get_rpccred_rcu(struct rpc_cred *cred)
{
	if (atomic_inc_not_zero(&cred->cr_count))
		return cred;
	return NULL;
}

#endif /* __KERNEL__ */
#endif /* _LINUX_SUNRPC_AUTH_H */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/include/linux/sunrpc/auth.h
	3	*
	4	* Declarations for the RPC client authentication machinery.
	5	*
	6	* Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
	7	*/
	8
	9	#ifndef _LINUX_SUNRPC_AUTH_H
	10	#define _LINUX_SUNRPC_AUTH_H
	11
	12	#ifdef __KERNEL__
	13
1da177e4 LT	14	#include <linux/sunrpc/sched.h>
	15	#include <linux/sunrpc/msg_prot.h>
	16	#include <linux/sunrpc/xdr.h>
	17
60063497	18	#include <linux/atomic.h>
31be5bf1	19	#include <linux/rcupdate.h>
7eaf040b	20	#include <linux/uidgid.h>
24a9a961	21	#include <linux/utsname.h>
1da177e4	22
4500632f CL	23	/*
	24	* Maximum size of AUTH_NONE authentication information, in XDR words.
	25	*/
	26	#define NUL_CALLSLACK (4)
	27	#define NUL_REPLYSLACK (2)
	28
24a9a961 JL	29	/*
	30	* Size of the nodename buffer. RFC1831 specifies a hard limit of 255 bytes,
	31	* but Linux hostnames are actually limited to __NEW_UTS_LEN bytes.
	32	*/
	33	#define UNX_MAXNODENAME __NEW_UTS_LEN
4500632f	34	#define UNX_CALLSLACK (21 + XDR_QUADLEN(UNX_MAXNODENAME))
1da177e4	35
9568c5e9 CL	36	struct rpcsec_gss_info;
9568c5e9 CL	37
4de6caa2 AA	38	/* auth_cred ac_flags bits */
	39	enum {
	40	RPC_CRED_NO_CRKEY_TIMEOUT = 0, /* underlying cred has no key timeout */
	41	RPC_CRED_KEY_EXPIRE_SOON = 1, /* underlying cred key will expire soon */
	42	RPC_CRED_NOTIFY_TIMEOUT = 2, /* nofity generic cred when underlying
	43	key will expire soon */
	44	};
	45
1da177e4 LT	46	/* Work around the lack of a VFS credential */
1da177e4 LT	47	struct auth_cred {
7eaf040b EB	48	kuid_t uid;
7eaf040b EB	49	kgid_t gid;
1da177e4	50	struct group_info *group_info;
68c97153	51	const char *principal;
4de6caa2	52	unsigned long ac_flags;
7c67db3a	53	unsigned char machine_cred : 1;
1da177e4 LT	54	};
	55
	56	/*
	57	* Client user credentials
	58	*/
4a8c1344 TM	59	struct rpc_auth;
4a8c1344 TM	60	struct rpc_credops;
1da177e4 LT	61	struct rpc_cred {
1da177e4 LT	62	struct hlist_node cr_hash; /* hash chain */
e092bdcd	63	struct list_head cr_lru; /* lru garbage collection */
31be5bf1	64	struct rcu_head cr_rcu;
4a8c1344	65	struct rpc_auth * cr_auth;
f1c0a861	66	const struct rpc_credops *cr_ops;
f895b252	67	#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
1da177e4 LT	68	unsigned long cr_magic; /* 0x0f4aa4f0 */
1da177e4 LT	69	#endif
fc432dd9 TM	70	unsigned long cr_expire; /* when to gc */
	71	unsigned long cr_flags; /* various flags */
	72	atomic_t cr_count; /* ref count */
1da177e4	73
7eaf040b	74	kuid_t cr_uid;
1da177e4 LT	75
	76	/* per-flavor data */
	77	};
fc432dd9 TM	78	#define RPCAUTH_CRED_NEW 0
fc432dd9 TM	79	#define RPCAUTH_CRED_UPTODATE 1
31be5bf1	80	#define RPCAUTH_CRED_HASHED 2
126e216a	81	#define RPCAUTH_CRED_NEGATIVE 3
1da177e4 LT	82
	83	#define RPCAUTH_CRED_MAGIC 0x0f4aa4f0
	84
	85	/*
	86	* Client authentication handle
	87	*/
241269bd	88	struct rpc_cred_cache;
4a8c1344	89	struct rpc_authops;
1da177e4 LT	90	struct rpc_auth {
1da177e4 LT	91	unsigned int au_cslack; /* call cred size estimate */
24b2605b BF	92	/* guess at number of u32's auth adds before
	93	* reply data; normally the verifier size: */
	94	unsigned int au_rslack;
	95	/* for gss, used to calculate au_rslack: */
	96	unsigned int au_verfsize;
	97
1da177e4	98	unsigned int au_flags; /* various flags */
f1c0a861	99	const struct rpc_authops au_ops; / operations */
1da177e4 LT	100	rpc_authflavor_t au_flavor; /* pseudoflavor (note may
	101	* differ from the flavor in
	102	* au_ops->au_flavor in gss
	103	* case) */
	104	atomic_t au_count; /* Reference counter */
	105
	106	struct rpc_cred_cache * au_credcache;
	107	/* per-flavor data */
	108	};
1da177e4	109
c2190661 TM	110	struct rpc_auth_create_args {
	111	rpc_authflavor_t pseudoflavor;
	112	const char *target_name;
	113	};
	114
8a317760 TM	115	/* Flags for rpcauth_lookupcred() */
8a317760 TM	116	#define RPCAUTH_LOOKUP_NEW 0x01 /* Accept an uninitialised cred */
bd956080	117	#define RPCAUTH_LOOKUP_RCU 0x02 /* lock-less lookup */
8a317760	118
1da177e4 LT	119	/*
	120	* Client authentication ops
	121	*/
	122	struct rpc_authops {
	123	struct module *owner;
	124	rpc_authflavor_t au_flavor; /* flavor (RPC_AUTH_) /
1da177e4	125	char * au_name;
c2190661	126	struct rpc_auth * (create)(struct rpc_auth_create_args , struct rpc_clnt *);
1da177e4 LT	127	void (destroy)(struct rpc_auth );
	128
	129	struct rpc_cred * (lookup_cred)(struct rpc_auth , struct auth_cred *, int);
3c6e0bc8	130	struct rpc_cred * (crcreate)(struct rpc_auth, struct auth_cred *, int, gfp_t);
6a1a1e34	131	int (list_pseudoflavors)(rpc_authflavor_t , int);
9568c5e9	132	rpc_authflavor_t (info2flavor)(struct rpcsec_gss_info );
a77c806f CL	133	int (*flavor2info)(rpc_authflavor_t,
a77c806f CL	134	struct rpcsec_gss_info *);
4de6caa2 AA	135	int (key_timeout)(struct rpc_auth ,
4de6caa2 AA	136	struct rpc_cred *);
1da177e4 LT	137	};
	138
	139	struct rpc_credops {
	140	const char * cr_name; /* Name of the auth flavour */
fba3bad4	141	int (cr_init)(struct rpc_auth , struct rpc_cred *);
1da177e4 LT	142	void (crdestroy)(struct rpc_cred );
	143
	144	int (crmatch)(struct auth_cred , struct rpc_cred *, int);
8572b8e2	145	struct rpc_cred * (crbind)(struct rpc_task , struct rpc_cred *, int);
d8ed029d	146	__be32 * (crmarshal)(struct rpc_task , __be32 *);
1da177e4	147	int (crrefresh)(struct rpc_task );
d8ed029d	148	__be32 * (crvalidate)(struct rpc_task , __be32 *);
9f06c719	149	int (crwrap_req)(struct rpc_task , kxdreproc_t,
d8ed029d	150	void , __be32 , void *);
bf269551	151	int (crunwrap_resp)(struct rpc_task , kxdrdproc_t,
d8ed029d	152	void , __be32 , void *);
4de6caa2 AA	153	int (crkey_timeout)(struct rpc_cred );
4de6caa2 AA	154	bool (crkey_to_expire)(struct rpc_cred );
a0337d1d	155	char * (crstringify_acceptor)(struct rpc_cred );
1da177e4 LT	156	};
1da177e4 LT	157
f1c0a861 TM	158	extern const struct rpc_authops authunix_ops;
f1c0a861 TM	159	extern const struct rpc_authops authnull_ops;
1da177e4	160
5d8d9a4d TM	161	int __init rpc_init_authunix(void);
	162	int __init rpc_init_generic_auth(void);
	163	int __init rpcauth_init_module(void);
c135e84a SR	164	void rpcauth_remove_module(void);
c135e84a SR	165	void rpc_destroy_generic_auth(void);
5d8d9a4d	166	void rpc_destroy_authunix(void);
9499b434	167
9a559efd	168	struct rpc_cred * rpc_lookup_cred(void);
bd956080	169	struct rpc_cred * rpc_lookup_cred_nonblock(void);
c065d229	170	struct rpc_cred * rpc_lookup_generic_cred(struct auth_cred *, int, gfp_t);
68c97153	171	struct rpc_cred * rpc_lookup_machine_cred(const char *service_name);
f1c0a861 TM	172	int rpcauth_register(const struct rpc_authops *);
f1c0a861 TM	173	int rpcauth_unregister(const struct rpc_authops *);
c2190661 TM	174	struct rpc_auth * rpcauth_create(struct rpc_auth_create_args *,
c2190661 TM	175	struct rpc_clnt *);
de7a8ce3	176	void rpcauth_release(struct rpc_auth *);
9568c5e9 CL	177	rpc_authflavor_t rpcauth_get_pseudoflavor(rpc_authflavor_t,
9568c5e9 CL	178	struct rpcsec_gss_info *);
a77c806f CL	179	int rpcauth_get_gssinfo(rpc_authflavor_t,
a77c806f CL	180	struct rpcsec_gss_info *);
6a1a1e34	181	int rpcauth_list_flavors(rpc_authflavor_t *, int);
3c6e0bc8	182	struct rpc_cred * rpcauth_lookup_credcache(struct rpc_auth , struct auth_cred , int, gfp_t);
5fe4755e	183	void rpcauth_init_cred(struct rpc_cred , const struct auth_cred , struct rpc_auth , const struct rpc_credops );
1da177e4	184	struct rpc_cred * rpcauth_lookupcred(struct rpc_auth *, int);
8572b8e2	185	struct rpc_cred * rpcauth_generic_bind_cred(struct rpc_task , struct rpc_cred , int);
1da177e4	186	void put_rpccred(struct rpc_cred *);
d8ed029d AD	187	__be32 * rpcauth_marshcred(struct rpc_task , __be32 );
d8ed029d AD	188	__be32 * rpcauth_checkverf(struct rpc_task , __be32 );
9f06c719	189	int rpcauth_wrap_req(struct rpc_task task, kxdreproc_t encode, void rqstp, __be32 data, void obj);
bf269551	190	int rpcauth_unwrap_resp(struct rpc_task task, kxdrdproc_t decode, void rqstp, __be32 data, void obj);
1da177e4 LT	191	int rpcauth_refreshcred(struct rpc_task *);
	192	void rpcauth_invalcred(struct rpc_task *);
	193	int rpcauth_uptodatecred(struct rpc_task *);
f5c2187c	194	int rpcauth_init_credcache(struct rpc_auth *);
3ab9bb72 TM	195	void rpcauth_destroy_credcache(struct rpc_auth *);
3ab9bb72 TM	196	void rpcauth_clear_credcache(struct rpc_cred_cache *);
4de6caa2 AA	197	int rpcauth_key_timeout_notify(struct rpc_auth *,
	198	struct rpc_cred *);
	199	bool rpcauth_cred_key_to_expire(struct rpc_cred *);
a0337d1d	200	char * rpcauth_stringify_acceptor(struct rpc_cred *);
1da177e4 LT	201
	202	static inline
	203	struct rpc_cred * get_rpccred(struct rpc_cred *cred)
	204	{
9a8f6b5e TM	205	if (cred != NULL)
9a8f6b5e TM	206	atomic_inc(&cred->cr_count);
1da177e4 LT	207	return cred;
	208	}
	209
62dbef2a JL	210	/**
	211	* get_rpccred_rcu - get a reference to a cred using rcu-protected pointer
	212	* @cred: cred of which to take a reference
	213	*
	214	* In some cases, we may have a pointer to a credential to which we
	215	* want to take a reference, but don't already have one. Because these
	216	* objects are freed using RCU, we can access the cr_count while its
	217	* on its way to destruction and only take a reference if it's not already
	218	* zero.
	219	*/
	220	static inline struct rpc_cred *
	221	get_rpccred_rcu(struct rpc_cred *cred)
	222	{
	223	if (atomic_inc_not_zero(&cred->cr_count))
	224	return cred;
	225	return NULL;
	226	}
	227
1da177e4 LT	228	#endif /* __KERNEL__ */
1da177e4 LT	229	#endif /* _LINUX_SUNRPC_AUTH_H */