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        char                    *cr_targ_princ;
  35        struct gss_api_mech     *cr_gss_mech;
  36};
  37
  38static inline void init_svc_cred(struct svc_cred *cred)
  39{
  40        cred->cr_group_info = NULL;
  41        cred->cr_raw_principal = NULL;
  42        cred->cr_principal = NULL;
  43        cred->cr_targ_princ = NULL;
  44        cred->cr_gss_mech = NULL;
  45}
  46
  47static inline void free_svc_cred(struct svc_cred *cred)
  48{
  49        if (cred->cr_group_info)
  50                put_group_info(cred->cr_group_info);
  51        kfree(cred->cr_raw_principal);
  52        kfree(cred->cr_principal);
  53        kfree(cred->cr_targ_princ);
  54        gss_mech_put(cred->cr_gss_mech);
  55        init_svc_cred(cred);
  56}
  57
  58struct svc_rqst;                /* forward decl */
  59struct in6_addr;
  60
  61/* Authentication is done in the context of a domain.
  62 *
  63 * Currently, the nfs server uses the auth_domain to stand
  64 * for the "client" listed in /etc/exports.
  65 *
  66 * More generally, a domain might represent a group of clients using
  67 * a common mechanism for authentication and having a common mapping
  68 * between local identity (uid) and network identity.  All clients
  69 * in a domain have similar general access rights.  Each domain can
  70 * contain multiple principals which will have different specific right
  71 * based on normal Discretionary Access Control.
  72 *
  73 * A domain is created by an authentication flavour module based on name
  74 * only.  Userspace then fills in detail on demand.
  75 *
  76 * In the case of auth_unix and auth_null, the auth_domain is also
  77 * associated with entries in another cache representing the mapping
  78 * of ip addresses to the given client.
  79 */
  80struct auth_domain {
  81        struct kref             ref;
  82        struct hlist_node       hash;
  83        char                    *name;
  84        struct auth_ops         *flavour;
  85        struct rcu_head         rcu_head;
  86};
  87
  88/*
  89 * Each authentication flavour registers an auth_ops
  90 * structure.
  91 * name is simply the name.
  92 * flavour gives the auth flavour. It determines where the flavour is registered
  93 * accept() is given a request and should verify it.
  94 *   It should inspect the authenticator and verifier, and possibly the data.
  95 *    If there is a problem with the authentication *authp should be set.
  96 *    The return value of accept() can indicate:
  97 *      OK - authorised. client and credential are set in rqstp.
  98 *           reqbuf points to arguments
  99 *           resbuf points to good place for results.  verfier
 100 *             is (probably) already in place.  Certainly space is
 101 *             reserved for it.
 102 *      DROP - simply drop the request. It may have been deferred
 103 *      GARBAGE - rpc garbage_args error
 104 *      SYSERR - rpc system_err error
 105 *      DENIED - authp holds reason for denial.
 106 *      COMPLETE - the reply is encoded already and ready to be sent; no
 107 *              further processing is necessary.  (This is used for processing
 108 *              null procedure calls which are used to set up encryption
 109 *              contexts.)
 110 *
 111 *   accept is passed the proc number so that it can accept NULL rpc requests
 112 *   even if it cannot authenticate the client (as is sometimes appropriate).
 113 *
 114 * release() is given a request after the procedure has been run.
 115 *  It should sign/encrypt the results if needed
 116 * It should return:
 117 *    OK - the resbuf is ready to be sent
 118 *    DROP - the reply should be quitely dropped
 119 *    DENIED - authp holds a reason for MSG_DENIED
 120 *    SYSERR - rpc system_err
 121 *
 122 * domain_release()
 123 *   This call releases a domain.
 124 * set_client()
 125 *   Givens a pending request (struct svc_rqst), finds and assigns
 126 *   an appropriate 'auth_domain' as the client.
 127 */
 128struct auth_ops {
 129        char *  name;
 130        struct module *owner;
 131        int     flavour;
 132        int     (*accept)(struct svc_rqst *rq, __be32 *authp);
 133        int     (*release)(struct svc_rqst *rq);
 134        void    (*domain_release)(struct auth_domain *);
 135        int     (*set_client)(struct svc_rqst *rq);
 136};
 137
 138#define SVC_GARBAGE     1
 139#define SVC_SYSERR      2
 140#define SVC_VALID       3
 141#define SVC_NEGATIVE    4
 142#define SVC_OK          5
 143#define SVC_DROP        6
 144#define SVC_CLOSE       7       /* Like SVC_DROP, but request is definitely
 145                                 * lost so if there is a tcp connection, it
 146                                 * should be closed
 147                                 */
 148#define SVC_DENIED      8
 149#define SVC_PENDING     9
 150#define SVC_COMPLETE    10
 151
 152struct svc_xprt;
 153
 154extern int      svc_authenticate(struct svc_rqst *rqstp, __be32 *authp);
 155extern int      svc_authorise(struct svc_rqst *rqstp);
 156extern int      svc_set_client(struct svc_rqst *rqstp);
 157extern int      svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops);
 158extern void     svc_auth_unregister(rpc_authflavor_t flavor);
 159
 160extern struct auth_domain *unix_domain_find(char *name);
 161extern void auth_domain_put(struct auth_domain *item);
 162extern int auth_unix_add_addr(struct net *net, struct in6_addr *addr, struct auth_domain *dom);
 163extern struct auth_domain *auth_domain_lookup(char *name, struct auth_domain *new);
 164extern struct auth_domain *auth_domain_find(char *name);
 165extern struct auth_domain *auth_unix_lookup(struct net *net, struct in6_addr *addr);
 166extern int auth_unix_forget_old(struct auth_domain *dom);
 167extern void svcauth_unix_purge(struct net *net);
 168extern void svcauth_unix_info_release(struct svc_xprt *xpt);
 169extern int svcauth_unix_set_client(struct svc_rqst *rqstp);
 170
 171extern int unix_gid_cache_create(struct net *net);
 172extern void unix_gid_cache_destroy(struct net *net);
 173
 174/*
 175 * The <stringhash.h> functions are good enough that we don't need to
 176 * use hash_32() on them; just extracting the high bits is enough.
 177 */
 178static inline unsigned long hash_str(char const *name, int bits)
 179{
 180        return hashlen_hash(hashlen_string(NULL, name)) >> (32 - bits);
 181}
 182
 183static inline unsigned long hash_mem(char const *buf, int length, int bits)
 184{
 185        return full_name_hash(NULL, buf, length) >> (32 - bits);
 186}
 187
 188#endif /* __KERNEL__ */
 189
 190#endif /* _LINUX_SUNRPC_SVCAUTH_H_ */
 191