LXR linux/include/linux/sunrpc/svcauth.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 * linux/include/linux/sunrpc/svcauth.h
   4 *
   5 * RPC server-side authentication stuff.
   6 *
   7 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
   8 */
   9
  10#ifndef _LINUX_SUNRPC_SVCAUTH_H_
  11#define _LINUX_SUNRPC_SVCAUTH_H_
  12
  13#ifdef __KERNEL__
  14
  15#include <linux/string.h>
  16#include <linux/sunrpc/msg_prot.h>
  17#include <linux/sunrpc/cache.h>
  18#include <linux/sunrpc/gss_api.h>
  19#include <linux/hash.h>
  20#include <linux/stringhash.h>
  21#include <linux/cred.h>
  22
  23struct svc_cred {
  24        kuid_t                  cr_uid;
  25        kgid_t                  cr_gid;
  26        struct group_info       *cr_group_info;
  27        u32                     cr_flavor; /* pseudoflavor */
  28        /* name of form servicetype/hostname@REALM, passed down by
  29         * gss-proxy: */
  30        char                    *cr_raw_principal;
  31        /* name of form servicetype@hostname, passed down by
  32         * rpc.svcgssd, or computed from the above: */
  33        char                    *cr_principal;
  34        struct gss_api_mech     *cr_gss_mech;
  35};
  36
  37static inline void init_svc_cred(struct svc_cred *cred)
  38{
  39        cred->cr_group_info = NULL;
  40        cred->cr_raw_principal = NULL;
  41        cred->cr_principal = NULL;
  42        cred->cr_gss_mech = NULL;
  43}
  44
  45static inline void free_svc_cred(struct svc_cred *cred)
  46{
  47        if (cred->cr_group_info)
  48                put_group_info(cred->cr_group_info);
  49        kfree(cred->cr_raw_principal);
  50        kfree(cred->cr_principal);
  51        gss_mech_put(cred->cr_gss_mech);
  52        init_svc_cred(cred);
  53}
  54
  55struct svc_rqst;                /* forward decl */
  56struct in6_addr;
  57
  58/* Authentication is done in the context of a domain.
  59 *
  60 * Currently, the nfs server uses the auth_domain to stand
  61 * for the "client" listed in /etc/exports.
  62 *
  63 * More generally, a domain might represent a group of clients using
  64 * a common mechanism for authentication and having a common mapping
  65 * between local identity (uid) and network identity.  All clients
  66 * in a domain have similar general access rights.  Each domain can
  67 * contain multiple principals which will have different specific right
  68 * based on normal Discretionary Access Control.
  69 *
  70 * A domain is created by an authentication flavour module based on name
  71 * only.  Userspace then fills in detail on demand.
  72 *
  73 * In the case of auth_unix and auth_null, the auth_domain is also
  74 * associated with entries in another cache representing the mapping
  75 * of ip addresses to the given client.
  76 */
  77struct auth_domain {
  78        struct kref             ref;
  79        struct hlist_node       hash;
  80        char                    *name;
  81        struct auth_ops         *flavour;
  82};
  83
  84/*
  85 * Each authentication flavour registers an auth_ops
  86 * structure.
  87 * name is simply the name.
  88 * flavour gives the auth flavour. It determines where the flavour is registered
  89 * accept() is given a request and should verify it.
  90 *   It should inspect the authenticator and verifier, and possibly the data.
  91 *    If there is a problem with the authentication *authp should be set.
  92 *    The return value of accept() can indicate:
  93 *      OK - authorised. client and credential are set in rqstp.
  94 *           reqbuf points to arguments
  95 *           resbuf points to good place for results.  verfier
  96 *             is (probably) already in place.  Certainly space is
  97 *             reserved for it.
  98 *      DROP - simply drop the request. It may have been deferred
  99 *      GARBAGE - rpc garbage_args error
 100 *      SYSERR - rpc system_err error
 101 *      DENIED - authp holds reason for denial.
 102 *      COMPLETE - the reply is encoded already and ready to be sent; no
 103 *              further processing is necessary.  (This is used for processing
 104 *              null procedure calls which are used to set up encryption
 105 *              contexts.)
 106 *
 107 *   accept is passed the proc number so that it can accept NULL rpc requests
 108 *   even if it cannot authenticate the client (as is sometimes appropriate).
 109 *
 110 * release() is given a request after the procedure has been run.
 111 *  It should sign/encrypt the results if needed
 112 * It should return:
 113 *    OK - the resbuf is ready to be sent
 114 *    DROP - the reply should be quitely dropped
 115 *    DENIED - authp holds a reason for MSG_DENIED
 116 *    SYSERR - rpc system_err
 117 *
 118 * domain_release()
 119 *   This call releases a domain.
 120 * set_client()
 121 *   Givens a pending request (struct svc_rqst), finds and assigns
 122 *   an appropriate 'auth_domain' as the client.
 123 */
 124struct auth_ops {
 125        char *  name;
 126        struct module *owner;
 127        int     flavour;
 128        int     (*accept)(struct svc_rqst *rq, __be32 *authp);
 129        int     (*release)(struct svc_rqst *rq);
 130        void    (*domain_release)(struct auth_domain *);
 131        int     (*set_client)(struct svc_rqst *rq);
 132};
 133
 134#define SVC_GARBAGE     1
 135#define SVC_SYSERR      2
 136#define SVC_VALID       3
 137#define SVC_NEGATIVE    4
 138#define SVC_OK          5
 139#define SVC_DROP        6
 140#define SVC_CLOSE       7       /* Like SVC_DROP, but request is definitely
 141                                 * lost so if there is a tcp connection, it
 142                                 * should be closed
 143                                 */
 144#define SVC_DENIED      8
 145#define SVC_PENDING     9
 146#define SVC_COMPLETE    10
 147
 148struct svc_xprt;
 149
 150extern int      svc_authenticate(struct svc_rqst *rqstp, __be32 *authp);
 151extern int      svc_authorise(struct svc_rqst *rqstp);
 152extern int      svc_set_client(struct svc_rqst *rqstp);
 153extern int      svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops);
 154extern void     svc_auth_unregister(rpc_authflavor_t flavor);
 155
 156extern struct auth_domain *unix_domain_find(char *name);
 157extern void auth_domain_put(struct auth_domain *item);
 158extern int auth_unix_add_addr(struct net *net, struct in6_addr *addr, struct auth_domain *dom);
 159extern struct auth_domain *auth_domain_lookup(char *name, struct auth_domain *new);
 160extern struct auth_domain *auth_domain_find(char *name);
 161extern struct auth_domain *auth_unix_lookup(struct net *net, struct in6_addr *addr);
 162extern int auth_unix_forget_old(struct auth_domain *dom);
 163extern void svcauth_unix_purge(struct net *net);
 164extern void svcauth_unix_info_release(struct svc_xprt *xpt);
 165extern int svcauth_unix_set_client(struct svc_rqst *rqstp);
 166
 167extern int unix_gid_cache_create(struct net *net);
 168extern void unix_gid_cache_destroy(struct net *net);
 169
 170/*
 171 * The <stringhash.h> functions are good enough that we don't need to
 172 * use hash_32() on them; just extracting the high bits is enough.
 173 */
 174static inline unsigned long hash_str(char const *name, int bits)
 175{
 176        return hashlen_hash(hashlen_string(NULL, name)) >> (32 - bits);
 177}
 178
 179static inline unsigned long hash_mem(char const *buf, int length, int bits)
 180{
 181        return full_name_hash(NULL, buf, length) >> (32 - bits);
 182}
 183
 184#endif /* __KERNEL__ */
 185
 186#endif /* _LINUX_SUNRPC_SVCAUTH_H_ */
 187