LXR linux/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/sunrpc/gss_api.h>
  18#include <linux/hash.h>
  19#include <linux/cred.h>
  20
  21struct svc_cred {
  22        kuid_t                  cr_uid;
  23        kgid_t                  cr_gid;
  24        struct group_info       *cr_group_info;
  25        u32                     cr_flavor; /* pseudoflavor */
  26        char                    *cr_principal; /* for gss */
  27        struct gss_api_mech     *cr_gss_mech;
  28};
  29
  30static inline void init_svc_cred(struct svc_cred *cred)
  31{
  32        cred->cr_group_info = NULL;
  33        cred->cr_principal = NULL;
  34        cred->cr_gss_mech = NULL;
  35}
  36
  37static inline void free_svc_cred(struct svc_cred *cred)
  38{
  39        if (cred->cr_group_info)
  40                put_group_info(cred->cr_group_info);
  41        kfree(cred->cr_principal);
  42        gss_mech_put(cred->cr_gss_mech);
  43        init_svc_cred(cred);
  44}
  45
  46struct svc_rqst;                /* forward decl */
  47struct in6_addr;
  48
  49/* Authentication is done in the context of a domain.
  50 *
  51 * Currently, the nfs server uses the auth_domain to stand
  52 * for the "client" listed in /etc/exports.
  53 *
  54 * More generally, a domain might represent a group of clients using
  55 * a common mechanism for authentication and having a common mapping
  56 * between local identity (uid) and network identity.  All clients
  57 * in a domain have similar general access rights.  Each domain can
  58 * contain multiple principals which will have different specific right
  59 * based on normal Discretionary Access Control.
  60 *
  61 * A domain is created by an authentication flavour module based on name
  62 * only.  Userspace then fills in detail on demand.
  63 *
  64 * In the case of auth_unix and auth_null, the auth_domain is also
  65 * associated with entries in another cache representing the mapping
  66 * of ip addresses to the given client.
  67 */
  68struct auth_domain {
  69        struct kref             ref;
  70        struct hlist_node       hash;
  71        char                    *name;
  72        struct auth_ops         *flavour;
  73};
  74
  75/*
  76 * Each authentication flavour registers an auth_ops
  77 * structure.
  78 * name is simply the name.
  79 * flavour gives the auth flavour. It determines where the flavour is registered
  80 * accept() is given a request and should verify it.
  81 *   It should inspect the authenticator and verifier, and possibly the data.
  82 *    If there is a problem with the authentication *authp should be set.
  83 *    The return value of accept() can indicate:
  84 *      OK - authorised. client and credential are set in rqstp.
  85 *           reqbuf points to arguments
  86 *           resbuf points to good place for results.  verfier
  87 *             is (probably) already in place.  Certainly space is
  88 *             reserved for it.
  89 *      DROP - simply drop the request. It may have been deferred
  90 *      GARBAGE - rpc garbage_args error
  91 *      SYSERR - rpc system_err error
  92 *      DENIED - authp holds reason for denial.
  93 *      COMPLETE - the reply is encoded already and ready to be sent; no
  94 *              further processing is necessary.  (This is used for processing
  95 *              null procedure calls which are used to set up encryption
  96 *              contexts.)
  97 *
  98 *   accept is passed the proc number so that it can accept NULL rpc requests
  99 *   even if it cannot authenticate the client (as is sometimes appropriate).
 100 *
 101 * release() is given a request after the procedure has been run.
 102 *  It should sign/encrypt the results if needed
 103 * It should return:
 104 *    OK - the resbuf is ready to be sent
 105 *    DROP - the reply should be quitely dropped
 106 *    DENIED - authp holds a reason for MSG_DENIED
 107 *    SYSERR - rpc system_err
 108 *
 109 * domain_release()
 110 *   This call releases a domain.
 111 * set_client()
 112 *   Givens a pending request (struct svc_rqst), finds and assigns
 113 *   an appropriate 'auth_domain' as the client.
 114 */
 115struct auth_ops {
 116        char *  name;
 117        struct module *owner;
 118        int     flavour;
 119        int     (*accept)(struct svc_rqst *rq, __be32 *authp);
 120        int     (*release)(struct svc_rqst *rq);
 121        void    (*domain_release)(struct auth_domain *);
 122        int     (*set_client)(struct svc_rqst *rq);
 123};
 124
 125#define SVC_GARBAGE     1
 126#define SVC_SYSERR      2
 127#define SVC_VALID       3
 128#define SVC_NEGATIVE    4
 129#define SVC_OK          5
 130#define SVC_DROP        6
 131#define SVC_CLOSE       7       /* Like SVC_DROP, but request is definitely
 132                                 * lost so if there is a tcp connection, it
 133                                 * should be closed
 134                                 */
 135#define SVC_DENIED      8
 136#define SVC_PENDING     9
 137#define SVC_COMPLETE    10
 138
 139struct svc_xprt;
 140
 141extern int      svc_authenticate(struct svc_rqst *rqstp, __be32 *authp);
 142extern int      svc_authorise(struct svc_rqst *rqstp);
 143extern int      svc_set_client(struct svc_rqst *rqstp);
 144extern int      svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops);
 145extern void     svc_auth_unregister(rpc_authflavor_t flavor);
 146
 147extern struct auth_domain *unix_domain_find(char *name);
 148extern void auth_domain_put(struct auth_domain *item);
 149extern int auth_unix_add_addr(struct net *net, struct in6_addr *addr, struct auth_domain *dom);
 150extern struct auth_domain *auth_domain_lookup(char *name, struct auth_domain *new);
 151extern struct auth_domain *auth_domain_find(char *name);
 152extern struct auth_domain *auth_unix_lookup(struct net *net, struct in6_addr *addr);
 153extern int auth_unix_forget_old(struct auth_domain *dom);
 154extern void svcauth_unix_purge(struct net *net);
 155extern void svcauth_unix_info_release(struct svc_xprt *xpt);
 156extern int svcauth_unix_set_client(struct svc_rqst *rqstp);
 157
 158extern int unix_gid_cache_create(struct net *net);
 159extern void unix_gid_cache_destroy(struct net *net);
 160
 161static inline unsigned long hash_str(char *name, int bits)
 162{
 163        unsigned long hash = 0;
 164        unsigned long l = 0;
 165        int len = 0;
 166        unsigned char c;
 167        do {
 168                if (unlikely(!(c = *name++))) {
 169                        c = (char)len; len = -1;
 170                }
 171                l = (l << 8) | c;
 172                len++;
 173                if ((len & (BITS_PER_LONG/8-1))==0)
 174                        hash = hash_long(hash^l, BITS_PER_LONG);
 175        } while (len);
 176        return hash >> (BITS_PER_LONG - bits);
 177}
 178
 179static inline unsigned long hash_mem(char *buf, int length, int bits)
 180{
 181        unsigned long hash = 0;
 182        unsigned long l = 0;
 183        int len = 0;
 184        unsigned char c;
 185        do {
 186                if (len == length) {
 187                        c = (char)len; len = -1;
 188                } else
 189                        c = *buf++;
 190                l = (l << 8) | c;
 191                len++;
 192                if ((len & (BITS_PER_LONG/8-1))==0)
 193                        hash = hash_long(hash^l, BITS_PER_LONG);
 194        } while (len);
 195        return hash >> (BITS_PER_LONG - bits);
 196}
 197
 198#endif /* __KERNEL__ */
 199
 200#endif /* _LINUX_SUNRPC_SVCAUTH_H_ */
 201