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