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#include <linux/sunrpc/sched.h>
  14#include <linux/sunrpc/msg_prot.h>
  15#include <linux/sunrpc/xdr.h>
  16
  17#include <linux/atomic.h>
  18#include <linux/rcupdate.h>
  19#include <linux/uidgid.h>
  20#include <linux/utsname.h>
  21
  22/*
  23 * Maximum size of AUTH_NONE authentication information, in XDR words.
  24 */
  25#define NUL_CALLSLACK   (4)
  26#define NUL_REPLYSLACK  (2)
  27
  28/*
  29 * Size of the nodename buffer. RFC1831 specifies a hard limit of 255 bytes,
  30 * but Linux hostnames are actually limited to __NEW_UTS_LEN bytes.
  31 */
  32#define UNX_MAXNODENAME __NEW_UTS_LEN
  33#define UNX_CALLSLACK   (21 + XDR_QUADLEN(UNX_MAXNODENAME))
  34#define UNX_NGROUPS     16
  35
  36struct rpcsec_gss_info;
  37
  38struct auth_cred {
  39        const struct cred *cred;
  40        const char *principal;  /* If present, this is a machine credential */
  41};
  42
  43/*
  44 * Client user credentials
  45 */
  46struct rpc_auth;
  47struct rpc_credops;
  48struct rpc_cred {
  49        struct hlist_node       cr_hash;        /* hash chain */
  50        struct list_head        cr_lru;         /* lru garbage collection */
  51        struct rcu_head         cr_rcu;
  52        struct rpc_auth *       cr_auth;
  53        const struct rpc_credops *cr_ops;
  54        unsigned long           cr_expire;      /* when to gc */
  55        unsigned long           cr_flags;       /* various flags */
  56        refcount_t              cr_count;       /* ref count */
  57        const struct cred       *cr_cred;
  58
  59        /* per-flavor data */
  60};
  61#define RPCAUTH_CRED_NEW        0
  62#define RPCAUTH_CRED_UPTODATE   1
  63#define RPCAUTH_CRED_HASHED     2
  64#define RPCAUTH_CRED_NEGATIVE   3
  65
  66const struct cred *rpc_machine_cred(void);
  67
  68/*
  69 * Client authentication handle
  70 */
  71struct rpc_cred_cache;
  72struct rpc_authops;
  73struct rpc_auth {
  74        unsigned int            au_cslack;      /* call cred size estimate */
  75        unsigned int            au_rslack;      /* reply cred size estimate */
  76        unsigned int            au_verfsize;    /* size of reply verifier */
  77        unsigned int            au_ralign;      /* words before UL header */
  78
  79        unsigned long           au_flags;
  80        const struct rpc_authops *au_ops;
  81        rpc_authflavor_t        au_flavor;      /* pseudoflavor (note may
  82                                                 * differ from the flavor in
  83                                                 * au_ops->au_flavor in gss
  84                                                 * case) */
  85        refcount_t              au_count;       /* Reference counter */
  86
  87        struct rpc_cred_cache * au_credcache;
  88        /* per-flavor data */
  89};
  90
  91/* rpc_auth au_flags */
  92#define RPCAUTH_AUTH_DATATOUCH          (1)
  93#define RPCAUTH_AUTH_UPDATE_SLACK       (2)
  94
  95struct rpc_auth_create_args {
  96        rpc_authflavor_t pseudoflavor;
  97        const char *target_name;
  98};
  99
 100/* Flags for rpcauth_lookupcred() */
 101#define RPCAUTH_LOOKUP_NEW              0x01    /* Accept an uninitialised cred */
 102
 103/*
 104 * Client authentication ops
 105 */
 106struct rpc_authops {
 107        struct module           *owner;
 108        rpc_authflavor_t        au_flavor;      /* flavor (RPC_AUTH_*) */
 109        char *                  au_name;
 110        struct rpc_auth *       (*create)(const struct rpc_auth_create_args *,
 111                                          struct rpc_clnt *);
 112        void                    (*destroy)(struct rpc_auth *);
 113
 114        int                     (*hash_cred)(struct auth_cred *, unsigned int);
 115        struct rpc_cred *       (*lookup_cred)(struct rpc_auth *, struct auth_cred *, int);
 116        struct rpc_cred *       (*crcreate)(struct rpc_auth*, struct auth_cred *, int, gfp_t);
 117        rpc_authflavor_t        (*info2flavor)(struct rpcsec_gss_info *);
 118        int                     (*flavor2info)(rpc_authflavor_t,
 119                                                struct rpcsec_gss_info *);
 120        int                     (*key_timeout)(struct rpc_auth *,
 121                                                struct rpc_cred *);
 122};
 123
 124struct rpc_credops {
 125        const char *            cr_name;        /* Name of the auth flavour */
 126        int                     (*cr_init)(struct rpc_auth *, struct rpc_cred *);
 127        void                    (*crdestroy)(struct rpc_cred *);
 128
 129        int                     (*crmatch)(struct auth_cred *, struct rpc_cred *, int);
 130        int                     (*crmarshal)(struct rpc_task *task,
 131                                             struct xdr_stream *xdr);
 132        int                     (*crrefresh)(struct rpc_task *);
 133        int                     (*crvalidate)(struct rpc_task *task,
 134                                              struct xdr_stream *xdr);
 135        int                     (*crwrap_req)(struct rpc_task *task,
 136                                              struct xdr_stream *xdr);
 137        int                     (*crunwrap_resp)(struct rpc_task *task,
 138                                                 struct xdr_stream *xdr);
 139        int                     (*crkey_timeout)(struct rpc_cred *);
 140        char *                  (*crstringify_acceptor)(struct rpc_cred *);
 141        bool                    (*crneed_reencode)(struct rpc_task *);
 142};
 143
 144extern const struct rpc_authops authunix_ops;
 145extern const struct rpc_authops authnull_ops;
 146
 147int __init              rpc_init_authunix(void);
 148int __init              rpcauth_init_module(void);
 149void                    rpcauth_remove_module(void);
 150void                    rpc_destroy_authunix(void);
 151
 152int                     rpcauth_register(const struct rpc_authops *);
 153int                     rpcauth_unregister(const struct rpc_authops *);
 154struct rpc_auth *       rpcauth_create(const struct rpc_auth_create_args *,
 155                                struct rpc_clnt *);
 156void                    rpcauth_release(struct rpc_auth *);
 157rpc_authflavor_t        rpcauth_get_pseudoflavor(rpc_authflavor_t,
 158                                struct rpcsec_gss_info *);
 159int                     rpcauth_get_gssinfo(rpc_authflavor_t,
 160                                struct rpcsec_gss_info *);
 161struct rpc_cred *       rpcauth_lookup_credcache(struct rpc_auth *, struct auth_cred *, int, gfp_t);
 162void                    rpcauth_init_cred(struct rpc_cred *, const struct auth_cred *, struct rpc_auth *, const struct rpc_credops *);
 163struct rpc_cred *       rpcauth_lookupcred(struct rpc_auth *, int);
 164void                    put_rpccred(struct rpc_cred *);
 165int                     rpcauth_marshcred(struct rpc_task *task,
 166                                          struct xdr_stream *xdr);
 167int                     rpcauth_checkverf(struct rpc_task *task,
 168                                          struct xdr_stream *xdr);
 169int                     rpcauth_wrap_req_encode(struct rpc_task *task,
 170                                                struct xdr_stream *xdr);
 171int                     rpcauth_wrap_req(struct rpc_task *task,
 172                                         struct xdr_stream *xdr);
 173int                     rpcauth_unwrap_resp_decode(struct rpc_task *task,
 174                                                   struct xdr_stream *xdr);
 175int                     rpcauth_unwrap_resp(struct rpc_task *task,
 176                                            struct xdr_stream *xdr);
 177bool                    rpcauth_xmit_need_reencode(struct rpc_task *task);
 178int                     rpcauth_refreshcred(struct rpc_task *);
 179void                    rpcauth_invalcred(struct rpc_task *);
 180int                     rpcauth_uptodatecred(struct rpc_task *);
 181int                     rpcauth_init_credcache(struct rpc_auth *);
 182void                    rpcauth_destroy_credcache(struct rpc_auth *);
 183void                    rpcauth_clear_credcache(struct rpc_cred_cache *);
 184char *                  rpcauth_stringify_acceptor(struct rpc_cred *);
 185
 186static inline
 187struct rpc_cred *get_rpccred(struct rpc_cred *cred)
 188{
 189        if (cred != NULL && refcount_inc_not_zero(&cred->cr_count))
 190                return cred;
 191        return NULL;
 192}
 193
 194#endif /* _LINUX_SUNRPC_AUTH_H */
 195