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
  20 struct svc_cred {
  21         uid_t                   cr_uid;
  22         gid_t                   cr_gid;
  23         struct group_info       *cr_group_info;
  24 };
  25
  26 struct svc_rqst;                /* forward decl */
  27
  28 /* Authentication is done in the context of a domain.
  29  * For a server, a domain represents a group of clients using
  30  * a common mechanism for authentication and having a common mapping
  31  * between local identity (uid) and network identity.  All clients
  32  * in a domain have similar general access rights.  Each domain can
  33  * contain multiple principals which will have different specific right
  34  * based on normal Discretionary Access Control.
  35  *
  36  * For a client, a domain represents a number of servers which all
  37  * use a common authentication mechanism and network identity name space.
  38  *
  39  * A domain is created by an authentication flavour module based on name
  40  * only.  Userspace then fills in detail on demand.
  41  *
  42  * The creation of a domain typically implies creation of one or
  43  * more caches for storing domain specific information.
  44  */
  45 struct auth_domain {
  46         struct  cache_head      h;
  47         char                    *name;
  48         int                     flavour;
  49 };
  50
  51 /*
  52  * Each authentication flavour registers an auth_ops
  53  * structure.
  54  * name is simply the name.
  55  * flavour gives the auth flavour. It determines where the flavour is registered
  56  * accept() is given a request and should verify it.
  57  *   It should inspect the authenticator and verifier, and possibly the data.
  58  *    If there is a problem with the authentication *authp should be set.
  59  *    The return value of accept() can indicate:
  60  *      OK - authorised. client and credential are set in rqstp.
  61  *           reqbuf points to arguments
  62  *           resbuf points to good place for results.  verfier
  63  *             is (probably) already in place.  Certainly space is
  64  *             reserved for it.
  65  *      DROP - simply drop the request. It may have been deferred
  66  *      GARBAGE - rpc garbage_args error
  67  *      SYSERR - rpc system_err error
  68  *      DENIED - authp holds reason for denial.
  69  *      COMPLETE - the reply is encoded already and ready to be sent; no
  70  *              further processing is necessary.  (This is used for processing
  71  *              null procedure calls which are used to set up encryption
  72  *              contexts.)
  73  *
  74  *   accept is passed the proc number so that it can accept NULL rpc requests
  75  *   even if it cannot authenticate the client (as is sometimes appropriate).
  76  *
  77  * release() is given a request after the procedure has been run.
  78  *  It should sign/encrypt the results if needed
  79  * It should return:
  80  *    OK - the resbuf is ready to be sent
  81  *    DROP - the reply should be quitely dropped
  82  *    DENIED - authp holds a reason for MSG_DENIED
  83  *    SYSERR - rpc system_err
  84  *
  85  * domain_release()
  86  *   This call releases a domain.
  87  */
  88 struct auth_ops {
  89         char *  name;
  90         struct module *owner;
  91         int     flavour;
  92         int     (*accept)(struct svc_rqst *rq, u32 *authp);
  93         int     (*release)(struct svc_rqst *rq);
  94         void    (*domain_release)(struct auth_domain *);
  95 };
  96
  97 #define SVC_GARBAGE     1
  98 #define SVC_SYSERR      2
  99 #define SVC_VALID       3
 100 #define SVC_NEGATIVE    4
 101 #define SVC_OK          5
 102 #define SVC_DROP        6
 103 #define SVC_DENIED      7
 104 #define SVC_PENDING     8
 105 #define SVC_COMPLETE    9
 106
 107
 108 extern int      svc_authenticate(struct svc_rqst *rqstp, u32 *authp);
 109 extern int      svc_authorise(struct svc_rqst *rqstp);
 110 extern int      svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops);
 111 extern void     svc_auth_unregister(rpc_authflavor_t flavor);
 112
 113 extern struct auth_domain *unix_domain_find(char *name);
 114 extern void auth_domain_put(struct auth_domain *item);
 115 extern int auth_unix_add_addr(struct in_addr addr, struct auth_domain *dom);
 116 extern struct auth_domain *auth_domain_lookup(struct auth_domain *item, int set);
 117 extern struct auth_domain *auth_domain_find(char *name);
 118 extern struct auth_domain *auth_unix_lookup(struct in_addr addr);
 119 extern int auth_unix_forget_old(struct auth_domain *dom);
 120 extern void svcauth_unix_purge(void);
 121
 122 static inline unsigned long hash_str(char *name, int bits)
 123 {
 124         unsigned long hash = 0;
 125         unsigned long l = 0;
 126         int len = 0;
 127         unsigned char c;
 128         do {
 129                 if (unlikely(!(c = *name++))) {
 130                         c = (char)len; len = -1;
 131                 }
 132                 l = (l << 8) | c;
 133                 len++;
 134                 if ((len & (BITS_PER_LONG/8-1))==0)
 135                         hash = hash_long(hash^l, BITS_PER_LONG);
 136         } while (len);
 137         return hash >> (BITS_PER_LONG - bits);
 138 }
 139
 140 static inline unsigned long hash_mem(char *buf, int length, int bits)
 141 {
 142         unsigned long hash = 0;
 143         unsigned long l = 0;
 144         int len = 0;
 145         unsigned char c;
 146         do {
 147                 if (len == length) {
 148                         c = (char)len; len = -1;
 149                 } else
 150                         c = *buf++;
 151                 l = (l << 8) | c;
 152                 len++;
 153                 if ((len & (BITS_PER_LONG/8-1))==0)
 154                         hash = hash_long(hash^l, BITS_PER_LONG);
 155         } while (len);
 156         return hash >> (BITS_PER_LONG - bits);
 157 }
 158
 159 extern struct cache_detail auth_domain_cache, ip_map_cache;
 160
 161 #endif /* __KERNEL__ */
 162
 163 #endif /* _LINUX_SUNRPC_SVCAUTH_H_ */