[thirdparty/kernel/linux.git] / include / linux / sunrpc / auth.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * 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))
#define UNX_NGROUPS	16

struct rpcsec_gss_info;

/* auth_cred ac_flags bits */
enum {
	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;
	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

/* rpc_auth au_flags */
#define RPCAUTH_AUTH_NO_CRKEY_TIMEOUT	0x0001 /* underlying cred has no key timeout */

/*
 * 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 */
};

/* rpc_auth au_flags */
#define RPCAUTH_AUTH_DATATOUCH	0x00000002

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 *);

	int			(*hash_cred)(struct auth_cred *, unsigned int);
	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_auth *, 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
b2441318	1	/* SPDX-License-Identifier: GPL-2.0 */
1da177e4 LT	2	/*
	3	* linux/include/linux/sunrpc/auth.h
	4	*
	5	* Declarations for the RPC client authentication machinery.
	6	*
	7	* Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
	8	*/
	9
	10	#ifndef _LINUX_SUNRPC_AUTH_H
	11	#define _LINUX_SUNRPC_AUTH_H
	12
	13	#ifdef __KERNEL__
	14
1da177e4 LT	15	#include <linux/sunrpc/sched.h>
	16	#include <linux/sunrpc/msg_prot.h>
	17	#include <linux/sunrpc/xdr.h>
	18
60063497	19	#include <linux/atomic.h>
31be5bf1	20	#include <linux/rcupdate.h>
7eaf040b	21	#include <linux/uidgid.h>
24a9a961	22	#include <linux/utsname.h>
1da177e4	23
4500632f CL	24	/*
	25	* Maximum size of AUTH_NONE authentication information, in XDR words.
	26	*/
	27	#define NUL_CALLSLACK (4)
	28	#define NUL_REPLYSLACK (2)
	29
24a9a961 JL	30	/*
	31	* Size of the nodename buffer. RFC1831 specifies a hard limit of 255 bytes,
	32	* but Linux hostnames are actually limited to __NEW_UTS_LEN bytes.
	33	*/
	34	#define UNX_MAXNODENAME __NEW_UTS_LEN
4500632f	35	#define UNX_CALLSLACK (21 + XDR_QUADLEN(UNX_MAXNODENAME))
5786461b	36	#define UNX_NGROUPS 16
1da177e4	37
9568c5e9 CL	38	struct rpcsec_gss_info;
9568c5e9 CL	39
4de6caa2 AA	40	/* auth_cred ac_flags bits */
4de6caa2 AA	41	enum {
4de6caa2 AA	42	RPC_CRED_KEY_EXPIRE_SOON = 1, /* underlying cred key will expire soon */
	43	RPC_CRED_NOTIFY_TIMEOUT = 2, /* nofity generic cred when underlying
	44	key will expire soon */
	45	};
	46
1da177e4 LT	47	/* Work around the lack of a VFS credential */
1da177e4 LT	48	struct auth_cred {
7eaf040b EB	49	kuid_t uid;
7eaf040b EB	50	kgid_t gid;
1da177e4	51	struct group_info *group_info;
68c97153	52	const char *principal;
4de6caa2	53	unsigned long ac_flags;
7c67db3a	54	unsigned char machine_cred : 1;
1da177e4 LT	55	};
	56
	57	/*
	58	* Client user credentials
	59	*/
4a8c1344 TM	60	struct rpc_auth;
4a8c1344 TM	61	struct rpc_credops;
1da177e4 LT	62	struct rpc_cred {
1da177e4 LT	63	struct hlist_node cr_hash; /* hash chain */
e092bdcd	64	struct list_head cr_lru; /* lru garbage collection */
31be5bf1	65	struct rcu_head cr_rcu;
4a8c1344	66	struct rpc_auth * cr_auth;
f1c0a861	67	const struct rpc_credops *cr_ops;
fc432dd9 TM	68	unsigned long cr_expire; /* when to gc */
	69	unsigned long cr_flags; /* various flags */
	70	atomic_t cr_count; /* ref count */
1da177e4	71
7eaf040b	72	kuid_t cr_uid;
1da177e4 LT	73
	74	/* per-flavor data */
	75	};
fc432dd9 TM	76	#define RPCAUTH_CRED_NEW 0
fc432dd9 TM	77	#define RPCAUTH_CRED_UPTODATE 1
31be5bf1	78	#define RPCAUTH_CRED_HASHED 2
126e216a	79	#define RPCAUTH_CRED_NEGATIVE 3
1da177e4	80
ce52914e SM	81	/* rpc_auth au_flags */
	82	#define RPCAUTH_AUTH_NO_CRKEY_TIMEOUT 0x0001 /* underlying cred has no key timeout */
	83
1da177e4 LT	84	/*
	85	* Client authentication handle
	86	*/
241269bd	87	struct rpc_cred_cache;
4a8c1344	88	struct rpc_authops;
1da177e4 LT	89	struct rpc_auth {
1da177e4 LT	90	unsigned int au_cslack; /* call cred size estimate */
24b2605b BF	91	/* guess at number of u32's auth adds before
	92	* reply data; normally the verifier size: */
	93	unsigned int au_rslack;
	94	/* for gss, used to calculate au_rslack: */
	95	unsigned int au_verfsize;
	96
1da177e4	97	unsigned int au_flags; /* various flags */
f1c0a861	98	const struct rpc_authops au_ops; / operations */
1da177e4 LT	99	rpc_authflavor_t au_flavor; /* pseudoflavor (note may
	100	* differ from the flavor in
	101	* au_ops->au_flavor in gss
	102	* case) */
	103	atomic_t au_count; /* Reference counter */
	104
	105	struct rpc_cred_cache * au_credcache;
	106	/* per-flavor data */
	107	};
1da177e4	108
65b80179 CL	109	/* rpc_auth au_flags */
	110	#define RPCAUTH_AUTH_DATATOUCH 0x00000002
	111
c2190661 TM	112	struct rpc_auth_create_args {
	113	rpc_authflavor_t pseudoflavor;
	114	const char *target_name;
	115	};
	116
8a317760 TM	117	/* Flags for rpcauth_lookupcred() */
8a317760 TM	118	#define RPCAUTH_LOOKUP_NEW 0x01 /* Accept an uninitialised cred */
bd956080	119	#define RPCAUTH_LOOKUP_RCU 0x02 /* lock-less lookup */
8a317760	120
1da177e4 LT	121	/*
	122	* Client authentication ops
	123	*/
	124	struct rpc_authops {
	125	struct module *owner;
	126	rpc_authflavor_t au_flavor; /* flavor (RPC_AUTH_) /
1da177e4	127	char * au_name;
c2190661	128	struct rpc_auth * (create)(struct rpc_auth_create_args , struct rpc_clnt *);
1da177e4 LT	129	void (destroy)(struct rpc_auth );
1da177e4 LT	130
e856a231	131	int (hash_cred)(struct auth_cred , unsigned int);
1da177e4	132	struct rpc_cred * (lookup_cred)(struct rpc_auth , struct auth_cred *, int);
3c6e0bc8	133	struct rpc_cred * (crcreate)(struct rpc_auth, struct auth_cred *, int, gfp_t);
6a1a1e34	134	int (list_pseudoflavors)(rpc_authflavor_t , int);
9568c5e9	135	rpc_authflavor_t (info2flavor)(struct rpcsec_gss_info );
a77c806f CL	136	int (*flavor2info)(rpc_authflavor_t,
a77c806f CL	137	struct rpcsec_gss_info *);
4de6caa2 AA	138	int (key_timeout)(struct rpc_auth ,
4de6caa2 AA	139	struct rpc_cred *);
1da177e4 LT	140	};
	141
	142	struct rpc_credops {
	143	const char * cr_name; /* Name of the auth flavour */
fba3bad4	144	int (cr_init)(struct rpc_auth , struct rpc_cred *);
1da177e4 LT	145	void (crdestroy)(struct rpc_cred );
	146
	147	int (crmatch)(struct auth_cred , struct rpc_cred *, int);
8572b8e2	148	struct rpc_cred * (crbind)(struct rpc_task , struct rpc_cred *, int);
d8ed029d	149	__be32 * (crmarshal)(struct rpc_task , __be32 *);
1da177e4	150	int (crrefresh)(struct rpc_task );
d8ed029d	151	__be32 * (crvalidate)(struct rpc_task , __be32 *);
9f06c719	152	int (crwrap_req)(struct rpc_task , kxdreproc_t,
d8ed029d	153	void , __be32 , void *);
bf269551	154	int (crunwrap_resp)(struct rpc_task , kxdrdproc_t,
d8ed029d	155	void , __be32 , void *);
4de6caa2 AA	156	int (crkey_timeout)(struct rpc_cred );
4de6caa2 AA	157	bool (crkey_to_expire)(struct rpc_cred );
a0337d1d	158	char * (crstringify_acceptor)(struct rpc_cred );
1da177e4 LT	159	};
1da177e4 LT	160
f1c0a861 TM	161	extern const struct rpc_authops authunix_ops;
f1c0a861 TM	162	extern const struct rpc_authops authnull_ops;
1da177e4	163
5d8d9a4d TM	164	int __init rpc_init_authunix(void);
	165	int __init rpc_init_generic_auth(void);
	166	int __init rpcauth_init_module(void);
c135e84a SR	167	void rpcauth_remove_module(void);
c135e84a SR	168	void rpc_destroy_generic_auth(void);
5d8d9a4d	169	void rpc_destroy_authunix(void);
9499b434	170
9a559efd	171	struct rpc_cred * rpc_lookup_cred(void);
bd956080	172	struct rpc_cred * rpc_lookup_cred_nonblock(void);
c065d229	173	struct rpc_cred * rpc_lookup_generic_cred(struct auth_cred *, int, gfp_t);
68c97153	174	struct rpc_cred * rpc_lookup_machine_cred(const char *service_name);
f1c0a861 TM	175	int rpcauth_register(const struct rpc_authops *);
f1c0a861 TM	176	int rpcauth_unregister(const struct rpc_authops *);
c2190661 TM	177	struct rpc_auth * rpcauth_create(struct rpc_auth_create_args *,
c2190661 TM	178	struct rpc_clnt *);
de7a8ce3	179	void rpcauth_release(struct rpc_auth *);
9568c5e9 CL	180	rpc_authflavor_t rpcauth_get_pseudoflavor(rpc_authflavor_t,
9568c5e9 CL	181	struct rpcsec_gss_info *);
a77c806f CL	182	int rpcauth_get_gssinfo(rpc_authflavor_t,
a77c806f CL	183	struct rpcsec_gss_info *);
6a1a1e34	184	int rpcauth_list_flavors(rpc_authflavor_t *, int);
3c6e0bc8	185	struct rpc_cred * rpcauth_lookup_credcache(struct rpc_auth , struct auth_cred , int, gfp_t);
5fe4755e	186	void rpcauth_init_cred(struct rpc_cred , const struct auth_cred , struct rpc_auth , const struct rpc_credops );
1da177e4	187	struct rpc_cred * rpcauth_lookupcred(struct rpc_auth *, int);
8572b8e2	188	struct rpc_cred * rpcauth_generic_bind_cred(struct rpc_task , struct rpc_cred , int);
1da177e4	189	void put_rpccred(struct rpc_cred *);
d8ed029d AD	190	__be32 * rpcauth_marshcred(struct rpc_task , __be32 );
d8ed029d AD	191	__be32 * rpcauth_checkverf(struct rpc_task , __be32 );
9f06c719	192	int rpcauth_wrap_req(struct rpc_task task, kxdreproc_t encode, void rqstp, __be32 data, void obj);
bf269551	193	int rpcauth_unwrap_resp(struct rpc_task task, kxdrdproc_t decode, void rqstp, __be32 data, void obj);
1da177e4 LT	194	int rpcauth_refreshcred(struct rpc_task *);
	195	void rpcauth_invalcred(struct rpc_task *);
	196	int rpcauth_uptodatecred(struct rpc_task *);
f5c2187c	197	int rpcauth_init_credcache(struct rpc_auth *);
3ab9bb72 TM	198	void rpcauth_destroy_credcache(struct rpc_auth *);
3ab9bb72 TM	199	void rpcauth_clear_credcache(struct rpc_cred_cache *);
4de6caa2 AA	200	int rpcauth_key_timeout_notify(struct rpc_auth *,
4de6caa2 AA	201	struct rpc_cred *);
ce52914e	202	bool rpcauth_cred_key_to_expire(struct rpc_auth , struct rpc_cred );
a0337d1d	203	char * rpcauth_stringify_acceptor(struct rpc_cred *);
1da177e4 LT	204
	205	static inline
	206	struct rpc_cred * get_rpccred(struct rpc_cred *cred)
	207	{
9a8f6b5e TM	208	if (cred != NULL)
9a8f6b5e TM	209	atomic_inc(&cred->cr_count);
1da177e4 LT	210	return cred;
	211	}
	212
62dbef2a JL	213	/**
	214	* get_rpccred_rcu - get a reference to a cred using rcu-protected pointer
	215	* @cred: cred of which to take a reference
	216	*
	217	* In some cases, we may have a pointer to a credential to which we
	218	* want to take a reference, but don't already have one. Because these
	219	* objects are freed using RCU, we can access the cr_count while its
	220	* on its way to destruction and only take a reference if it's not already
	221	* zero.
	222	*/
	223	static inline struct rpc_cred *
	224	get_rpccred_rcu(struct rpc_cred *cred)
	225	{
	226	if (atomic_inc_not_zero(&cred->cr_count))
	227	return cred;
	228	return NULL;
	229	}
	230
1da177e4 LT	231	#endif /* __KERNEL__ */
1da177e4 LT	232	#endif /* _LINUX_SUNRPC_AUTH_H */