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
  20 struct svc_cred {
  21         uid_t                   cr_uid;
  22         gid_t                   cr_gid;
  23         struct group_info       *cr_group_info;
  24         u32                     cr_flavor; /* pseudoflavor */
  25         char                    *cr_principal; /* for gss */
  26 };
  27
  28 static 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
  35 struct svc_rqst;                /* forward decl */
  36 struct 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  */
  57 struct 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  */
 104 struct 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
 128 struct svc_xprt;
 129
 130 extern int      svc_authenticate(struct svc_rqst *rqstp, __be32 *authp);
 131 extern int      svc_authorise(struct svc_rqst *rqstp);
 132 extern int      svc_set_client(struct svc_rqst *rqstp);
 133 extern int      svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops);
 134 extern void     svc_auth_unregister(rpc_authflavor_t flavor);
 135
 136 extern struct auth_domain *unix_domain_find(char *name);
 137 extern void auth_domain_put(struct auth_domain *item);
 138 extern int auth_unix_add_addr(struct net *net, struct in6_addr *addr, struct auth_domain *dom);
 139 extern struct auth_domain *auth_domain_lookup(char *name, struct auth_domain *new);
 140 extern struct auth_domain *auth_domain_find(char *name);
 141 extern struct auth_domain *auth_unix_lookup(struct net *net, struct in6_addr *addr);
 142 extern int auth_unix_forget_old(struct auth_domain *dom);
 143 extern void svcauth_unix_purge(struct net *net);
 144 extern void svcauth_unix_info_release(struct svc_xprt *xpt);
 145 extern int svcauth_unix_set_client(struct svc_rqst *rqstp);
 146
 147 extern int unix_gid_cache_create(struct net *net);
 148 extern void unix_gid_cache_destroy(struct net *net);
 149
 150 static 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
 168 static 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_ */