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
  19#define SVC_CRED_NGROUPS        32
  20struct svc_cred {
  21        uid_t                   cr_uid;
  22        gid_t                   cr_gid;
  23        struct group_info       *cr_group_info;
  24};
  25
  26struct svc_rqst;                /* forward decl */
  27struct 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 */
  48struct 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 */
  95struct 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_DENIED      7
 112#define SVC_PENDING     8
 113#define SVC_COMPLETE    9
 114
 115
 116extern int      svc_authenticate(struct svc_rqst *rqstp, __be32 *authp);
 117extern int      svc_authorise(struct svc_rqst *rqstp);
 118extern int      svc_set_client(struct svc_rqst *rqstp);
 119extern int      svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops);
 120extern void     svc_auth_unregister(rpc_authflavor_t flavor);
 121
 122extern struct auth_domain *unix_domain_find(char *name);
 123extern void auth_domain_put(struct auth_domain *item);
 124extern int auth_unix_add_addr(struct in6_addr *addr, struct auth_domain *dom);
 125extern struct auth_domain *auth_domain_lookup(char *name, struct auth_domain *new);
 126extern struct auth_domain *auth_domain_find(char *name);
 127extern struct auth_domain *auth_unix_lookup(struct in6_addr *addr);
 128extern int auth_unix_forget_old(struct auth_domain *dom);
 129extern void svcauth_unix_purge(void);
 130extern void svcauth_unix_info_release(void *);
 131extern int svcauth_unix_set_client(struct svc_rqst *rqstp);
 132
 133static inline unsigned long hash_str(char *name, int bits)
 134{
 135        unsigned long hash = 0;
 136        unsigned long l = 0;
 137        int len = 0;
 138        unsigned char c;
 139        do {
 140                if (unlikely(!(c = *name++))) {
 141                        c = (char)len; len = -1;
 142                }
 143                l = (l << 8) | c;
 144                len++;
 145                if ((len & (BITS_PER_LONG/8-1))==0)
 146                        hash = hash_long(hash^l, BITS_PER_LONG);
 147        } while (len);
 148        return hash >> (BITS_PER_LONG - bits);
 149}
 150
 151static inline unsigned long hash_mem(char *buf, int length, int bits)
 152{
 153        unsigned long hash = 0;
 154        unsigned long l = 0;
 155        int len = 0;
 156        unsigned char c;
 157        do {
 158                if (len == length) {
 159                        c = (char)len; len = -1;
 160                } else
 161                        c = *buf++;
 162                l = (l << 8) | c;
 163                len++;
 164                if ((len & (BITS_PER_LONG/8-1))==0)
 165                        hash = hash_long(hash^l, BITS_PER_LONG);
 166        } while (len);
 167        return hash >> (BITS_PER_LONG - bits);
 168}
 169
 170#endif /* __KERNEL__ */
 171
 172#endif /* _LINUX_SUNRPC_SVCAUTH_H_ */
 173