include/linux/sunrpc/svcauth.h

   1 /*
   2  * linux/include/linux/sunrpc/svcauth.h
   3  *
   4  * RPC server-side authentication stuff.
   5  *
   6  * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
   7  */
   8
   9 #ifndef _LINUX_SUNRPC_SVCAUTH_H_
  10 #define _LINUX_SUNRPC_SVCAUTH_H_
  11
  12 #ifdef __KERNEL__
  13
  14 #include <linux/string.h>
  15 #include <linux/sunrpc/msg_prot.h>
  16 #include <linux/sunrpc/cache.h>
  17 #include <linux/hash.h>
  18
  19 #define SVC_CRED_NGROUPS        32
  20 struct svc_cred {
  21         uid_t                   cr_uid;
  22         gid_t                   cr_gid;
  23         struct group_info       *cr_group_info;
  24 };
  25
  26 struct svc_rqst;                /* forward decl */
  27 struct in6_addr;
  28
  29 /* Authentication is done in the context of a domain.
  30  *
  31  * Currently, the nfs server uses the auth_domain to stand
  32  * for the "client" listed in /etc/exports.
  33  *
  34  * More generally, a domain might represent a group of clients using
  35  * a common mechanism for authentication and having a common mapping
  36  * between local identity (uid) and network identity.  All clients
  37  * in a domain have similar general access rights.  Each domain can
  38  * contain multiple principals which will have different specific right
  39  * based on normal Discretionary Access Control.
  40  *
  41  * A domain is created by an authentication flavour module based on name
  42  * only.  Userspace then fills in detail on demand.
  43  *
  44  * In the case of auth_unix and auth_null, the auth_domain is also
  45  * associated with entries in another cache representing the mapping
  46  * of ip addresses to the given client.
  47  */
  48 struct auth_domain {
  49         struct kref             ref;
  50         struct hlist_node       hash;
  51         char                    *name;
  52         struct auth_ops         *flavour;
  53 };
  54
  55 /*
  56  * Each authentication flavour registers an auth_ops
  57  * structure.
  58  * name is simply the name.
  59  * flavour gives the auth flavour. It determines where the flavour is registered
  60  * accept() is given a request and should verify it.
  61  *   It should inspect the authenticator and verifier, and possibly the data.
  62  *    If there is a problem with the authentication *authp should be set.
  63  *    The return value of accept() can indicate:
  64  *      OK - authorised. client and credential are set in rqstp.
  65  *           reqbuf points to arguments
  66  *           resbuf points to good place for results.  verfier
  67  *             is (probably) already in place.  Certainly space is
  68  *             reserved for it.
  69  *      DROP - simply drop the request. It may have been deferred
  70  *      GARBAGE - rpc garbage_args error
  71  *      SYSERR - rpc system_err error
  72  *      DENIED - authp holds reason for denial.
  73  *      COMPLETE - the reply is encoded already and ready to be sent; no
  74  *              further processing is necessary.  (This is used for processing
  75  *              null procedure calls which are used to set up encryption
  76  *              contexts.)
  77  *
  78  *   accept is passed the proc number so that it can accept NULL rpc requests
  79  *   even if it cannot authenticate the client (as is sometimes appropriate).
  80  *
  81  * release() is given a request after the procedure has been run.
  82  *  It should sign/encrypt the results if needed
  83  * It should return:
  84  *    OK - the resbuf is ready to be sent
  85  *    DROP - the reply should be quitely dropped
  86  *    DENIED - authp holds a reason for MSG_DENIED
  87  *    SYSERR - rpc system_err
  88  *
  89  * domain_release()
  90  *   This call releases a domain.
  91  * set_client()
  92  *   Givens a pending request (struct svc_rqst), finds and assigns
  93  *   an appropriate 'auth_domain' as the client.
  94  */
  95 struct auth_ops {
  96         char *  name;
  97         struct module *owner;
  98         int     flavour;
  99         int     (*accept)(struct svc_rqst *rq, __be32 *authp);
 100         int     (*release)(struct svc_rqst *rq);
 101         void    (*domain_release)(struct auth_domain *);
 102         int     (*set_client)(struct svc_rqst *rq);
 103 };
 104
 105 #define SVC_GARBAGE     1
 106 #define SVC_SYSERR      2
 107 #define SVC_VALID       3
 108 #define SVC_NEGATIVE    4
 109 #define SVC_OK          5
 110 #define SVC_DROP        6
 111 #define SVC_CLOSE       7       /* Like SVC_DROP, but request is definitely
 112                                  * lost so if there is a tcp connection, it
 113                                  * should be closed
 114                                  */
 115 #define SVC_DENIED      8
 116 #define SVC_PENDING     9
 117 #define SVC_COMPLETE    10
 118
 119 struct svc_xprt;
 120
 121 extern int      svc_authenticate(struct svc_rqst *rqstp, __be32 *authp);
 122 extern int      svc_authorise(struct svc_rqst *rqstp);
 123 extern int      svc_set_client(struct svc_rqst *rqstp);
 124 extern int      svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops);
 125 extern void     svc_auth_unregister(rpc_authflavor_t flavor);
 126
 127 extern struct auth_domain *unix_domain_find(char *name);
 128 extern void auth_domain_put(struct auth_domain *item);
 129 extern int auth_unix_add_addr(struct net *net, struct in6_addr *addr, struct auth_domain *dom);
 130 extern struct auth_domain *auth_domain_lookup(char *name, struct auth_domain *new);
 131 extern struct auth_domain *auth_domain_find(char *name);
 132 extern struct auth_domain *auth_unix_lookup(struct net *net, struct in6_addr *addr);
 133 extern int auth_unix_forget_old(struct auth_domain *dom);
 134 extern void svcauth_unix_purge(void);
 135 extern void svcauth_unix_info_release(struct svc_xprt *xpt);
 136 extern int svcauth_unix_set_client(struct svc_rqst *rqstp);
 137
 138 static inline unsigned long hash_str(char *name, int bits)
 139 {
 140         unsigned long hash = 0;
 141         unsigned long l = 0;
 142         int len = 0;
 143         unsigned char c;
 144         do {
 145                 if (unlikely(!(c = *name++))) {
 146                         c = (char)len; len = -1;
 147                 }
 148                 l = (l << 8) | c;
 149                 len++;
 150                 if ((len & (BITS_PER_LONG/8-1))==0)
 151                         hash = hash_long(hash^l, BITS_PER_LONG);
 152         } while (len);
 153         return hash >> (BITS_PER_LONG - bits);
 154 }
 155
 156 static inline unsigned long hash_mem(char *buf, int length, int bits)
 157 {
 158         unsigned long hash = 0;
 159         unsigned long l = 0;
 160         int len = 0;
 161         unsigned char c;
 162         do {
 163                 if (len == length) {
 164                         c = (char)len; len = -1;
 165                 } else
 166                         c = *buf++;
 167                 l = (l << 8) | c;
 168                 len++;
 169                 if ((len & (BITS_PER_LONG/8-1))==0)
 170                         hash = hash_long(hash^l, BITS_PER_LONG);
 171         } while (len);
 172         return hash >> (BITS_PER_LONG - bits);
 173 }
 174
 175 #endif /* __KERNEL__ */
 176
 177 #endif /* _LINUX_SUNRPC_SVCAUTH_H_ */