/*
* 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_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
/* 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 *);
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 */
