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  * Size of the nodename buffer. RFC1831 specifies a hard limit of 255 bytes,
  25  * but Linux hostnames are actually limited to __NEW_UTS_LEN bytes.
  26  */
  27 #define UNX_MAXNODENAME __NEW_UTS_LEN
  28
  29 struct rpcsec_gss_info;
  30
  31 /* auth_cred ac_flags bits */
  32 enum {
  33         RPC_CRED_NO_CRKEY_TIMEOUT = 0, /* underlying cred has no key timeout */
  34         RPC_CRED_KEY_EXPIRE_SOON = 1, /* underlying cred key will expire soon */
  35         RPC_CRED_NOTIFY_TIMEOUT = 2,   /* nofity generic cred when underlying
  36                                         key will expire soon */
  37 };
  38
  39 /* Work around the lack of a VFS credential */
  40 struct auth_cred {
  41         kuid_t  uid;
  42         kgid_t  gid;
  43         struct group_info *group_info;
  44         const char *principal;
  45         unsigned long ac_flags;
  46         unsigned char machine_cred : 1;
  47 };
  48
  49 /*
  50  * Client user credentials
  51  */
  52 struct rpc_auth;
  53 struct rpc_credops;
  54 struct rpc_cred {
  55         struct hlist_node       cr_hash;        /* hash chain */
  56         struct list_head        cr_lru;         /* lru garbage collection */
  57         struct rcu_head         cr_rcu;
  58         struct rpc_auth *       cr_auth;
  59         const struct rpc_credops *cr_ops;
  60 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
  61         unsigned long           cr_magic;       /* 0x0f4aa4f0 */
  62 #endif
  63         unsigned long           cr_expire;      /* when to gc */
  64         unsigned long           cr_flags;       /* various flags */
  65         atomic_t                cr_count;       /* ref count */
  66
  67         kuid_t                  cr_uid;
  68
  69         /* per-flavor data */
  70 };
  71 #define RPCAUTH_CRED_NEW        0
  72 #define RPCAUTH_CRED_UPTODATE   1
  73 #define RPCAUTH_CRED_HASHED     2
  74 #define RPCAUTH_CRED_NEGATIVE   3
  75
  76 #define RPCAUTH_CRED_MAGIC      0x0f4aa4f0
  77
  78 /*
  79  * Client authentication handle
  80  */
  81 struct rpc_cred_cache;
  82 struct rpc_authops;
  83 struct rpc_auth {
  84         unsigned int            au_cslack;      /* call cred size estimate */
  85                                 /* guess at number of u32's auth adds before
  86                                  * reply data; normally the verifier size: */
  87         unsigned int            au_rslack;
  88                                 /* for gss, used to calculate au_rslack: */
  89         unsigned int            au_verfsize;
  90
  91         unsigned int            au_flags;       /* various flags */
  92         const struct rpc_authops *au_ops;               /* operations */
  93         rpc_authflavor_t        au_flavor;      /* pseudoflavor (note may
  94                                                  * differ from the flavor in
  95                                                  * au_ops->au_flavor in gss
  96                                                  * case) */
  97         atomic_t                au_count;       /* Reference counter */
  98
  99         struct rpc_cred_cache * au_credcache;
 100         /* per-flavor data */
 101 };
 102
 103 struct rpc_auth_create_args {
 104         rpc_authflavor_t pseudoflavor;
 105         const char *target_name;
 106 };
 107
 108 /* Flags for rpcauth_lookupcred() */
 109 #define RPCAUTH_LOOKUP_NEW              0x01    /* Accept an uninitialised cred */
 110 #define RPCAUTH_LOOKUP_RCU              0x02    /* lock-less lookup */
 111
 112 /*
 113  * Client authentication ops
 114  */
 115 struct rpc_authops {
 116         struct module           *owner;
 117         rpc_authflavor_t        au_flavor;      /* flavor (RPC_AUTH_*) */
 118         char *                  au_name;
 119         struct rpc_auth *       (*create)(struct rpc_auth_create_args *, struct rpc_clnt *);
 120         void                    (*destroy)(struct rpc_auth *);
 121
 122         struct rpc_cred *       (*lookup_cred)(struct rpc_auth *, struct auth_cred *, int);
 123         struct rpc_cred *       (*crcreate)(struct rpc_auth*, struct auth_cred *, int);
 124         int                     (*list_pseudoflavors)(rpc_authflavor_t *, int);
 125         rpc_authflavor_t        (*info2flavor)(struct rpcsec_gss_info *);
 126         int                     (*flavor2info)(rpc_authflavor_t,
 127                                                 struct rpcsec_gss_info *);
 128         int                     (*key_timeout)(struct rpc_auth *,
 129                                                 struct rpc_cred *);
 130 };
 131
 132 struct rpc_credops {
 133         const char *            cr_name;        /* Name of the auth flavour */
 134         int                     (*cr_init)(struct rpc_auth *, struct rpc_cred *);
 135         void                    (*crdestroy)(struct rpc_cred *);
 136
 137         int                     (*crmatch)(struct auth_cred *, struct rpc_cred *, int);
 138         struct rpc_cred *       (*crbind)(struct rpc_task *, struct rpc_cred *, int);
 139         __be32 *                (*crmarshal)(struct rpc_task *, __be32 *);
 140         int                     (*crrefresh)(struct rpc_task *);
 141         __be32 *                (*crvalidate)(struct rpc_task *, __be32 *);
 142         int                     (*crwrap_req)(struct rpc_task *, kxdreproc_t,
 143                                                 void *, __be32 *, void *);
 144         int                     (*crunwrap_resp)(struct rpc_task *, kxdrdproc_t,
 145                                                 void *, __be32 *, void *);
 146         int                     (*crkey_timeout)(struct rpc_cred *);
 147         bool                    (*crkey_to_expire)(struct rpc_cred *);
 148         char *                  (*crstringify_acceptor)(struct rpc_cred *);
 149 };
 150
 151 extern const struct rpc_authops authunix_ops;
 152 extern const struct rpc_authops authnull_ops;
 153
 154 int __init              rpc_init_authunix(void);
 155 int __init              rpc_init_generic_auth(void);
 156 int __init              rpcauth_init_module(void);
 157 void                    rpcauth_remove_module(void);
 158 void                    rpc_destroy_generic_auth(void);
 159 void                    rpc_destroy_authunix(void);
 160
 161 struct rpc_cred *       rpc_lookup_cred(void);
 162 struct rpc_cred *       rpc_lookup_cred_nonblock(void);
 163 struct rpc_cred *       rpc_lookup_machine_cred(const char *service_name);
 164 int                     rpcauth_register(const struct rpc_authops *);
 165 int                     rpcauth_unregister(const struct rpc_authops *);
 166 struct rpc_auth *       rpcauth_create(struct rpc_auth_create_args *,
 167                                 struct rpc_clnt *);
 168 void                    rpcauth_release(struct rpc_auth *);
 169 rpc_authflavor_t        rpcauth_get_pseudoflavor(rpc_authflavor_t,
 170                                 struct rpcsec_gss_info *);
 171 int                     rpcauth_get_gssinfo(rpc_authflavor_t,
 172                                 struct rpcsec_gss_info *);
 173 int                     rpcauth_list_flavors(rpc_authflavor_t *, int);
 174 struct rpc_cred *       rpcauth_lookup_credcache(struct rpc_auth *, struct auth_cred *, int);
 175 void                    rpcauth_init_cred(struct rpc_cred *, const struct auth_cred *, struct rpc_auth *, const struct rpc_credops *);
 176 struct rpc_cred *       rpcauth_lookupcred(struct rpc_auth *, int);
 177 struct rpc_cred *       rpcauth_generic_bind_cred(struct rpc_task *, struct rpc_cred *, int);
 178 void                    put_rpccred(struct rpc_cred *);
 179 __be32 *                rpcauth_marshcred(struct rpc_task *, __be32 *);
 180 __be32 *                rpcauth_checkverf(struct rpc_task *, __be32 *);
 181 int                     rpcauth_wrap_req(struct rpc_task *task, kxdreproc_t encode, void *rqstp, __be32 *data, void *obj);
 182 int                     rpcauth_unwrap_resp(struct rpc_task *task, kxdrdproc_t decode, void *rqstp, __be32 *data, void *obj);
 183 int                     rpcauth_refreshcred(struct rpc_task *);
 184 void                    rpcauth_invalcred(struct rpc_task *);
 185 int                     rpcauth_uptodatecred(struct rpc_task *);
 186 int                     rpcauth_init_credcache(struct rpc_auth *);
 187 void                    rpcauth_destroy_credcache(struct rpc_auth *);
 188 void                    rpcauth_clear_credcache(struct rpc_cred_cache *);
 189 int                     rpcauth_key_timeout_notify(struct rpc_auth *,
 190                                                 struct rpc_cred *);
 191 bool                    rpcauth_cred_key_to_expire(struct rpc_cred *);
 192 char *                  rpcauth_stringify_acceptor(struct rpc_cred *);
 193
 194 static inline
 195 struct rpc_cred *       get_rpccred(struct rpc_cred *cred)
 196 {
 197         atomic_inc(&cred->cr_count);
 198         return cred;
 199 }
 200
 201 #endif /* __KERNEL__ */
 202 #endif /* _LINUX_SUNRPC_AUTH_H */