LXR linux/include/linux/sunrpc/auth.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   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
  15#include <linux/sunrpc/sched.h>
  16#include <linux/sunrpc/msg_prot.h>
  17#include <linux/sunrpc/xdr.h>
  18
  19#include <linux/atomic.h>
  20#include <linux/rcupdate.h>
  21#include <linux/uidgid.h>
  22#include <linux/utsname.h>
  23
  24/*
  25 * Maximum size of AUTH_NONE authentication information, in XDR words.
  26 */
  27#define NUL_CALLSLACK   (4)
  28#define NUL_REPLYSLACK  (2)
  29
  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
  35#define UNX_CALLSLACK   (21 + XDR_QUADLEN(UNX_MAXNODENAME))
  36#define UNX_NGROUPS     16
  37
  38struct rpcsec_gss_info;
  39
  40struct auth_cred {
  41        const struct cred *cred;
  42        const char *principal;  /* If present, this is a machine credential */
  43};
  44
  45/*
  46 * Client user credentials
  47 */
  48struct rpc_auth;
  49struct rpc_credops;
  50struct rpc_cred {
  51        struct hlist_node       cr_hash;        /* hash chain */
  52        struct list_head        cr_lru;         /* lru garbage collection */
  53        struct rcu_head         cr_rcu;
  54        struct rpc_auth *       cr_auth;
  55        const struct rpc_credops *cr_ops;
  56        unsigned long           cr_expire;      /* when to gc */
  57        unsigned long           cr_flags;       /* various flags */
  58        refcount_t              cr_count;       /* ref count */
  59        const struct cred       *cr_cred;
  60
  61        /* per-flavor data */
  62};
  63#define RPCAUTH_CRED_NEW        0
  64#define RPCAUTH_CRED_UPTODATE   1
  65#define RPCAUTH_CRED_HASHED     2
  66#define RPCAUTH_CRED_NEGATIVE   3
  67
  68const struct cred *rpc_machine_cred(void);
  69
  70/*
  71 * Client authentication handle
  72 */
  73struct rpc_cred_cache;
  74struct rpc_authops;
  75struct rpc_auth {
  76        unsigned int            au_cslack;      /* call cred size estimate */
  77        unsigned int            au_rslack;      /* reply cred size estimate */
  78        unsigned int            au_verfsize;    /* size of reply verifier */
  79        unsigned int            au_ralign;      /* words before UL header */
  80
  81        unsigned int            au_flags;
  82        const struct rpc_authops *au_ops;
  83        rpc_authflavor_t        au_flavor;      /* pseudoflavor (note may
  84                                                 * differ from the flavor in
  85                                                 * au_ops->au_flavor in gss
  86                                                 * case) */
  87        refcount_t              au_count;       /* Reference counter */
  88
  89        struct rpc_cred_cache * au_credcache;
  90        /* per-flavor data */
  91};
  92
  93/* rpc_auth au_flags */
  94#define RPCAUTH_AUTH_DATATOUCH  0x00000002
  95
  96struct rpc_auth_create_args {
  97        rpc_authflavor_t pseudoflavor;
  98        const char *target_name;
  99};
 100
 101/* Flags for rpcauth_lookupcred() */
 102#define RPCAUTH_LOOKUP_NEW              0x01    /* Accept an uninitialised cred */
 103
 104/*
 105 * Client authentication ops
 106 */
 107struct rpc_authops {
 108        struct module           *owner;
 109        rpc_authflavor_t        au_flavor;      /* flavor (RPC_AUTH_*) */
 110        char *                  au_name;
 111        struct rpc_auth *       (*create)(const struct rpc_auth_create_args *,
 112                                          struct rpc_clnt *);
 113        void                    (*destroy)(struct rpc_auth *);
 114
 115        int                     (*hash_cred)(struct auth_cred *, unsigned int);
 116        struct rpc_cred *       (*lookup_cred)(struct rpc_auth *, struct auth_cred *, int);
 117        struct rpc_cred *       (*crcreate)(struct rpc_auth*, struct auth_cred *, int, gfp_t);
 118        int                     (*list_pseudoflavors)(rpc_authflavor_t *, int);
 119        rpc_authflavor_t        (*info2flavor)(struct rpcsec_gss_info *);
 120        int                     (*flavor2info)(rpc_authflavor_t,
 121                                                struct rpcsec_gss_info *);
 122        int                     (*key_timeout)(struct rpc_auth *,
 123                                                struct rpc_cred *);
 124};
 125
 126struct rpc_credops {
 127        const char *            cr_name;        /* Name of the auth flavour */
 128        int                     (*cr_init)(struct rpc_auth *, struct rpc_cred *);
 129        void                    (*crdestroy)(struct rpc_cred *);
 130
 131        int                     (*crmatch)(struct auth_cred *, struct rpc_cred *, int);
 132        int                     (*crmarshal)(struct rpc_task *task,
 133                                             struct xdr_stream *xdr);
 134        int                     (*crrefresh)(struct rpc_task *);
 135        int                     (*crvalidate)(struct rpc_task *task,
 136                                              struct xdr_stream *xdr);
 137        int                     (*crwrap_req)(struct rpc_task *task,
 138                                              struct xdr_stream *xdr);
 139        int                     (*crunwrap_resp)(struct rpc_task *task,
 140                                                 struct xdr_stream *xdr);
 141        int                     (*crkey_timeout)(struct rpc_cred *);
 142        char *                  (*crstringify_acceptor)(struct rpc_cred *);
 143        bool                    (*crneed_reencode)(struct rpc_task *);
 144};
 145
 146extern const struct rpc_authops authunix_ops;
 147extern const struct rpc_authops authnull_ops;
 148
 149int __init              rpc_init_authunix(void);
 150int __init              rpcauth_init_module(void);
 151void                    rpcauth_remove_module(void);
 152void                    rpc_destroy_authunix(void);
 153
 154int                     rpcauth_register(const struct rpc_authops *);
 155int                     rpcauth_unregister(const struct rpc_authops *);
 156struct rpc_auth *       rpcauth_create(const struct rpc_auth_create_args *,
 157                                struct rpc_clnt *);
 158void                    rpcauth_release(struct rpc_auth *);
 159rpc_authflavor_t        rpcauth_get_pseudoflavor(rpc_authflavor_t,
 160                                struct rpcsec_gss_info *);
 161int                     rpcauth_get_gssinfo(rpc_authflavor_t,
 162                                struct rpcsec_gss_info *);
 163int                     rpcauth_list_flavors(rpc_authflavor_t *, int);
 164struct rpc_cred *       rpcauth_lookup_credcache(struct rpc_auth *, struct auth_cred *, int, gfp_t);
 165void                    rpcauth_init_cred(struct rpc_cred *, const struct auth_cred *, struct rpc_auth *, const struct rpc_credops *);
 166struct rpc_cred *       rpcauth_lookupcred(struct rpc_auth *, int);
 167void                    put_rpccred(struct rpc_cred *);
 168int                     rpcauth_marshcred(struct rpc_task *task,
 169                                          struct xdr_stream *xdr);
 170int                     rpcauth_checkverf(struct rpc_task *task,
 171                                          struct xdr_stream *xdr);
 172int                     rpcauth_wrap_req_encode(struct rpc_task *task,
 173                                                struct xdr_stream *xdr);
 174int                     rpcauth_wrap_req(struct rpc_task *task,
 175                                         struct xdr_stream *xdr);
 176int                     rpcauth_unwrap_resp_decode(struct rpc_task *task,
 177                                                   struct xdr_stream *xdr);
 178int                     rpcauth_unwrap_resp(struct rpc_task *task,
 179                                            struct xdr_stream *xdr);
 180bool                    rpcauth_xmit_need_reencode(struct rpc_task *task);
 181int                     rpcauth_refreshcred(struct rpc_task *);
 182void                    rpcauth_invalcred(struct rpc_task *);
 183int                     rpcauth_uptodatecred(struct rpc_task *);
 184int                     rpcauth_init_credcache(struct rpc_auth *);
 185void                    rpcauth_destroy_credcache(struct rpc_auth *);
 186void                    rpcauth_clear_credcache(struct rpc_cred_cache *);
 187char *                  rpcauth_stringify_acceptor(struct rpc_cred *);
 188
 189static inline
 190struct rpc_cred *get_rpccred(struct rpc_cred *cred)
 191{
 192        if (cred != NULL && refcount_inc_not_zero(&cred->cr_count))
 193                return cred;
 194        return NULL;
 195}
 196
 197#endif /* __KERNEL__ */
 198#endif /* _LINUX_SUNRPC_AUTH_H */
 199