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/sunrpc/gss_api.h>
  18 #include <linux/hash.h>
  19 #include <linux/cred.h>
  20
  21 struct svc_cred {
  22         kuid_t                  cr_uid;
  23         kgid_t                  cr_gid;
  24         struct group_info       *cr_group_info;
  25         u32                     cr_flavor; /* pseudoflavor */
  26         /* name of form servicetype/hostname@REALM, passed down by
  27          * gss-proxy: */
  28         char                    *cr_raw_principal;
  29         /* name of form servicetype@hostname, passed down by
  30          * rpc.svcgssd, or computed from the above: */
  31         char                    *cr_principal;
  32         struct gss_api_mech     *cr_gss_mech;
  33 };
  34
  35 static inline void init_svc_cred(struct svc_cred *cred)
  36 {
  37         cred->cr_group_info = NULL;
  38         cred->cr_raw_principal = NULL;
  39         cred->cr_principal = NULL;
  40         cred->cr_gss_mech = NULL;
  41 }
  42
  43 static inline void free_svc_cred(struct svc_cred *cred)
  44 {
  45         if (cred->cr_group_info)
  46                 put_group_info(cred->cr_group_info);
  47         kfree(cred->cr_raw_principal);
  48         kfree(cred->cr_principal);
  49         gss_mech_put(cred->cr_gss_mech);
  50         init_svc_cred(cred);
  51 }
  52
  53 struct svc_rqst;                /* forward decl */
  54 struct in6_addr;
  55
  56 /* Authentication is done in the context of a domain.
  57  *
  58  * Currently, the nfs server uses the auth_domain to stand
  59  * for the "client" listed in /etc/exports.
  60  *
  61  * More generally, a domain might represent a group of clients using
  62  * a common mechanism for authentication and having a common mapping
  63  * between local identity (uid) and network identity.  All clients
  64  * in a domain have similar general access rights.  Each domain can
  65  * contain multiple principals which will have different specific right
  66  * based on normal Discretionary Access Control.
  67  *
  68  * A domain is created by an authentication flavour module based on name
  69  * only.  Userspace then fills in detail on demand.
  70  *
  71  * In the case of auth_unix and auth_null, the auth_domain is also
  72  * associated with entries in another cache representing the mapping
  73  * of ip addresses to the given client.
  74  */
  75 struct auth_domain {
  76         struct kref             ref;
  77         struct hlist_node       hash;
  78         char                    *name;
  79         struct auth_ops         *flavour;
  80 };
  81
  82 /*
  83  * Each authentication flavour registers an auth_ops
  84  * structure.
  85  * name is simply the name.
  86  * flavour gives the auth flavour. It determines where the flavour is registered
  87  * accept() is given a request and should verify it.
  88  *   It should inspect the authenticator and verifier, and possibly the data.
  89  *    If there is a problem with the authentication *authp should be set.
  90  *    The return value of accept() can indicate:
  91  *      OK - authorised. client and credential are set in rqstp.
  92  *           reqbuf points to arguments
  93  *           resbuf points to good place for results.  verfier
  94  *             is (probably) already in place.  Certainly space is
  95  *             reserved for it.
  96  *      DROP - simply drop the request. It may have been deferred
  97  *      GARBAGE - rpc garbage_args error
  98  *      SYSERR - rpc system_err error
  99  *      DENIED - authp holds reason for denial.
 100  *      COMPLETE - the reply is encoded already and ready to be sent; no
 101  *              further processing is necessary.  (This is used for processing
 102  *              null procedure calls which are used to set up encryption
 103  *              contexts.)
 104  *
 105  *   accept is passed the proc number so that it can accept NULL rpc requests
 106  *   even if it cannot authenticate the client (as is sometimes appropriate).
 107  *
 108  * release() is given a request after the procedure has been run.
 109  *  It should sign/encrypt the results if needed
 110  * It should return:
 111  *    OK - the resbuf is ready to be sent
 112  *    DROP - the reply should be quitely dropped
 113  *    DENIED - authp holds a reason for MSG_DENIED
 114  *    SYSERR - rpc system_err
 115  *
 116  * domain_release()
 117  *   This call releases a domain.
 118  * set_client()
 119  *   Givens a pending request (struct svc_rqst), finds and assigns
 120  *   an appropriate 'auth_domain' as the client.
 121  */
 122 struct auth_ops {
 123         char *  name;
 124         struct module *owner;
 125         int     flavour;
 126         int     (*accept)(struct svc_rqst *rq, __be32 *authp);
 127         int     (*release)(struct svc_rqst *rq);
 128         void    (*domain_release)(struct auth_domain *);
 129         int     (*set_client)(struct svc_rqst *rq);
 130 };
 131
 132 #define SVC_GARBAGE     1
 133 #define SVC_SYSERR      2
 134 #define SVC_VALID       3
 135 #define SVC_NEGATIVE    4
 136 #define SVC_OK          5
 137 #define SVC_DROP        6
 138 #define SVC_CLOSE       7       /* Like SVC_DROP, but request is definitely
 139                                  * lost so if there is a tcp connection, it
 140                                  * should be closed
 141                                  */
 142 #define SVC_DENIED      8
 143 #define SVC_PENDING     9
 144 #define SVC_COMPLETE    10
 145
 146 struct svc_xprt;
 147
 148 extern int      svc_authenticate(struct svc_rqst *rqstp, __be32 *authp);
 149 extern int      svc_authorise(struct svc_rqst *rqstp);
 150 extern int      svc_set_client(struct svc_rqst *rqstp);
 151 extern int      svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops);
 152 extern void     svc_auth_unregister(rpc_authflavor_t flavor);
 153
 154 extern struct auth_domain *unix_domain_find(char *name);
 155 extern void auth_domain_put(struct auth_domain *item);
 156 extern int auth_unix_add_addr(struct net *net, struct in6_addr *addr, struct auth_domain *dom);
 157 extern struct auth_domain *auth_domain_lookup(char *name, struct auth_domain *new);
 158 extern struct auth_domain *auth_domain_find(char *name);
 159 extern struct auth_domain *auth_unix_lookup(struct net *net, struct in6_addr *addr);
 160 extern int auth_unix_forget_old(struct auth_domain *dom);
 161 extern void svcauth_unix_purge(struct net *net);
 162 extern void svcauth_unix_info_release(struct svc_xprt *xpt);
 163 extern int svcauth_unix_set_client(struct svc_rqst *rqstp);
 164
 165 extern int unix_gid_cache_create(struct net *net);
 166 extern void unix_gid_cache_destroy(struct net *net);
 167
 168 static inline unsigned long hash_str(char *name, 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 (unlikely(!(c = *name++))) {
 176                         c = (char)len; len = -1;
 177                 }
 178                 l = (l << 8) | c;
 179                 len++;
 180                 if ((len & (BITS_PER_LONG/8-1))==0)
 181                         hash = hash_long(hash^l, BITS_PER_LONG);
 182         } while (len);
 183         return hash >> (BITS_PER_LONG - bits);
 184 }
 185
 186 static inline unsigned long hash_mem(char *buf, int length, int bits)
 187 {
 188         unsigned long hash = 0;
 189         unsigned long l = 0;
 190         int len = 0;
 191         unsigned char c;
 192         do {
 193                 if (len == length) {
 194                         c = (char)len; len = -1;
 195                 } else
 196                         c = *buf++;
 197                 l = (l << 8) | c;
 198                 len++;
 199                 if ((len & (BITS_PER_LONG/8-1))==0)
 200                         hash = hash_long(hash^l, BITS_PER_LONG);
 201         } while (len);
 202         return hash >> (BITS_PER_LONG - bits);
 203 }
 204
 205 #endif /* __KERNEL__ */
 206
 207 #endif /* _LINUX_SUNRPC_SVCAUTH_H_ */