include/linux/sunrpc/auth.h

   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
  14 #include <linux/sunrpc/sched.h>
  15 #include <linux/sunrpc/msg_prot.h>
  16 #include <linux/sunrpc/xdr.h>
  17
  18 #include <linux/atomic.h>
  19 #include <linux/rcupdate.h>
  20 #include <linux/uidgid.h>
  21 #include <linux/utsname.h>
  22
  23 /*
  24  * Maximum size of AUTH_NONE authentication information, in XDR words.
  25  */
  26 #define NUL_CALLSLACK   (4)
  27 #define NUL_REPLYSLACK  (2)
  28
  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
  34 #define UNX_CALLSLACK   (21 + XDR_QUADLEN(UNX_MAXNODENAME))
  35
  36 struct rpcsec_gss_info;
  37
  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
  46 /* Work around the lack of a VFS credential */
  47 struct auth_cred {
  48         kuid_t  uid;
  49         kgid_t  gid;
  50         struct group_info *group_info;
  51         const char *principal;
  52         unsigned long ac_flags;
  53         unsigned char machine_cred : 1;
  54 };
  55
  56 /*
  57  * Client user credentials
  58  */
  59 struct rpc_auth;
  60 struct rpc_credops;
  61 struct rpc_cred {
  62         struct hlist_node       cr_hash;        /* hash chain */
  63         struct list_head        cr_lru;         /* lru garbage collection */
  64         struct rcu_head         cr_rcu;
  65         struct rpc_auth *       cr_auth;
  66         const struct rpc_credops *cr_ops;
  67 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
  68         unsigned long           cr_magic;       /* 0x0f4aa4f0 */
  69 #endif
  70         unsigned long           cr_expire;      /* when to gc */
  71         unsigned long           cr_flags;       /* various flags */
  72         atomic_t                cr_count;       /* ref count */
  73
  74         kuid_t                  cr_uid;
  75
  76         /* per-flavor data */
  77 };
  78 #define RPCAUTH_CRED_NEW        0
  79 #define RPCAUTH_CRED_UPTODATE   1
  80 #define RPCAUTH_CRED_HASHED     2
  81 #define RPCAUTH_CRED_NEGATIVE   3
  82
  83 #define RPCAUTH_CRED_MAGIC      0x0f4aa4f0
  84
  85 /*
  86  * Client authentication handle
  87  */
  88 struct rpc_cred_cache;
  89 struct rpc_authops;
  90 struct rpc_auth {
  91         unsigned int            au_cslack;      /* call cred size estimate */
  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
  98         unsigned int            au_flags;       /* various flags */
  99         const struct rpc_authops *au_ops;               /* operations */
 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 };
 109
 110 struct rpc_auth_create_args {
 111         rpc_authflavor_t pseudoflavor;
 112         const char *target_name;
 113 };
 114
 115 /* Flags for rpcauth_lookupcred() */
 116 #define RPCAUTH_LOOKUP_NEW              0x01    /* Accept an uninitialised cred */
 117 #define RPCAUTH_LOOKUP_RCU              0x02    /* lock-less lookup */
 118
 119 /*
 120  * Client authentication ops
 121  */
 122 struct rpc_authops {
 123         struct module           *owner;
 124         rpc_authflavor_t        au_flavor;      /* flavor (RPC_AUTH_*) */
 125         char *                  au_name;
 126         struct rpc_auth *       (*create)(struct rpc_auth_create_args *, struct rpc_clnt *);
 127         void                    (*destroy)(struct rpc_auth *);
 128
 129         struct rpc_cred *       (*lookup_cred)(struct rpc_auth *, struct auth_cred *, int);
 130         struct rpc_cred *       (*crcreate)(struct rpc_auth*, struct auth_cred *, int);
 131         int                     (*list_pseudoflavors)(rpc_authflavor_t *, int);
 132         rpc_authflavor_t        (*info2flavor)(struct rpcsec_gss_info *);
 133         int                     (*flavor2info)(rpc_authflavor_t,
 134                                                 struct rpcsec_gss_info *);
 135         int                     (*key_timeout)(struct rpc_auth *,
 136                                                 struct rpc_cred *);
 137 };
 138
 139 struct rpc_credops {
 140         const char *            cr_name;        /* Name of the auth flavour */
 141         int                     (*cr_init)(struct rpc_auth *, struct rpc_cred *);
 142         void                    (*crdestroy)(struct rpc_cred *);
 143
 144         int                     (*crmatch)(struct auth_cred *, struct rpc_cred *, int);
 145         struct rpc_cred *       (*crbind)(struct rpc_task *, struct rpc_cred *, int);
 146         __be32 *                (*crmarshal)(struct rpc_task *, __be32 *);
 147         int                     (*crrefresh)(struct rpc_task *);
 148         __be32 *                (*crvalidate)(struct rpc_task *, __be32 *);
 149         int                     (*crwrap_req)(struct rpc_task *, kxdreproc_t,
 150                                                 void *, __be32 *, void *);
 151         int                     (*crunwrap_resp)(struct rpc_task *, kxdrdproc_t,
 152                                                 void *, __be32 *, void *);
 153         int                     (*crkey_timeout)(struct rpc_cred *);
 154         bool                    (*crkey_to_expire)(struct rpc_cred *);
 155         char *                  (*crstringify_acceptor)(struct rpc_cred *);
 156 };
 157
 158 extern const struct rpc_authops authunix_ops;
 159 extern const struct rpc_authops authnull_ops;
 160
 161 int __init              rpc_init_authunix(void);
 162 int __init              rpc_init_generic_auth(void);
 163 int __init              rpcauth_init_module(void);
 164 void                    rpcauth_remove_module(void);
 165 void                    rpc_destroy_generic_auth(void);
 166 void                    rpc_destroy_authunix(void);
 167
 168 struct rpc_cred *       rpc_lookup_cred(void);
 169 struct rpc_cred *       rpc_lookup_cred_nonblock(void);
 170 struct rpc_cred *       rpc_lookup_machine_cred(const char *service_name);
 171 int                     rpcauth_register(const struct rpc_authops *);
 172 int                     rpcauth_unregister(const struct rpc_authops *);
 173 struct rpc_auth *       rpcauth_create(struct rpc_auth_create_args *,
 174                                 struct rpc_clnt *);
 175 void                    rpcauth_release(struct rpc_auth *);
 176 rpc_authflavor_t        rpcauth_get_pseudoflavor(rpc_authflavor_t,
 177                                 struct rpcsec_gss_info *);
 178 int                     rpcauth_get_gssinfo(rpc_authflavor_t,
 179                                 struct rpcsec_gss_info *);
 180 int                     rpcauth_list_flavors(rpc_authflavor_t *, int);
 181 struct rpc_cred *       rpcauth_lookup_credcache(struct rpc_auth *, struct auth_cred *, int);
 182 void                    rpcauth_init_cred(struct rpc_cred *, const struct auth_cred *, struct rpc_auth *, const struct rpc_credops *);
 183 struct rpc_cred *       rpcauth_lookupcred(struct rpc_auth *, int);
 184 struct rpc_cred *       rpcauth_generic_bind_cred(struct rpc_task *, struct rpc_cred *, int);
 185 void                    put_rpccred(struct rpc_cred *);
 186 __be32 *                rpcauth_marshcred(struct rpc_task *, __be32 *);
 187 __be32 *                rpcauth_checkverf(struct rpc_task *, __be32 *);
 188 int                     rpcauth_wrap_req(struct rpc_task *task, kxdreproc_t encode, void *rqstp, __be32 *data, void *obj);
 189 int                     rpcauth_unwrap_resp(struct rpc_task *task, kxdrdproc_t decode, void *rqstp, __be32 *data, void *obj);
 190 int                     rpcauth_refreshcred(struct rpc_task *);
 191 void                    rpcauth_invalcred(struct rpc_task *);
 192 int                     rpcauth_uptodatecred(struct rpc_task *);
 193 int                     rpcauth_init_credcache(struct rpc_auth *);
 194 void                    rpcauth_destroy_credcache(struct rpc_auth *);
 195 void                    rpcauth_clear_credcache(struct rpc_cred_cache *);
 196 int                     rpcauth_key_timeout_notify(struct rpc_auth *,
 197                                                 struct rpc_cred *);
 198 bool                    rpcauth_cred_key_to_expire(struct rpc_cred *);
 199 char *                  rpcauth_stringify_acceptor(struct rpc_cred *);
 200
 201 static inline
 202 struct rpc_cred *       get_rpccred(struct rpc_cred *cred)
 203 {
 204         atomic_inc(&cred->cr_count);
 205         return cred;
 206 }
 207
 208 #endif /* __KERNEL__ */
 209 #endif /* _LINUX_SUNRPC_AUTH_H */