/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
 20struct svc_cred {
 21	uid_t			cr_uid;
 22	gid_t			cr_gid;
 23	struct group_info	*cr_group_info;
 24};
 25
 26struct svc_rqst;		/* forward decl */
 27struct in6_addr;
 28
 29/* Authentication is done in the context of a domain.
 30 *
 31 * Currently, the nfs server uses the auth_domain to stand
 32 * for the "client" listed in /etc/exports.
 33 *
 34 * More generally, a domain might represent a group of clients using
 35 * a common mechanism for authentication and having a common mapping
 36 * between local identity (uid) and network identity.  All clients
 37 * in a domain have similar general access rights.  Each domain can
 38 * contain multiple principals which will have different specific right
 39 * based on normal Discretionary Access Control.
 40 *
 41 * A domain is created by an authentication flavour module based on name
 42 * only.  Userspace then fills in detail on demand.
 43 *
 44 * In the case of auth_unix and auth_null, the auth_domain is also
 45 * associated with entries in another cache representing the mapping
 46 * of ip addresses to the given client.
 47 */
 48struct auth_domain {
 49	struct kref		ref;
 50	struct hlist_node	hash;
 51	char			*name;
 52	struct auth_ops		*flavour;
 53};
 54
 55/*
 56 * Each authentication flavour registers an auth_ops
 57 * structure.
 58 * name is simply the name.
 59 * flavour gives the auth flavour. It determines where the flavour is registered
 60 * accept() is given a request and should verify it.
 61 *   It should inspect the authenticator and verifier, and possibly the data.
 62 *    If there is a problem with the authentication *authp should be set.
 63 *    The return value of accept() can indicate:
 64 *      OK - authorised. client and credential are set in rqstp.
 65 *           reqbuf points to arguments
 66 *           resbuf points to good place for results.  verfier
 67 *             is (probably) already in place.  Certainly space is
 68 *	       reserved for it.
 69 *      DROP - simply drop the request. It may have been deferred
 70 *      GARBAGE - rpc garbage_args error
 71 *      SYSERR - rpc system_err error
 72 *      DENIED - authp holds reason for denial.
 73 *      COMPLETE - the reply is encoded already and ready to be sent; no
 74 *		further processing is necessary.  (This is used for processing
 75 *		null procedure calls which are used to set up encryption
 76 *		contexts.)
 77 *
 78 *   accept is passed the proc number so that it can accept NULL rpc requests
 79 *   even if it cannot authenticate the client (as is sometimes appropriate).
 80 *
 81 * release() is given a request after the procedure has been run.
 82 *  It should sign/encrypt the results if needed
 83 * It should return:
 84 *    OK - the resbuf is ready to be sent
 85 *    DROP - the reply should be quitely dropped
 86 *    DENIED - authp holds a reason for MSG_DENIED
 87 *    SYSERR - rpc system_err
 88 *
 89 * domain_release()
 90 *   This call releases a domain.
 91 * set_client()
 92 *   Givens a pending request (struct svc_rqst), finds and assigns
 93 *   an appropriate 'auth_domain' as the client.
 94 */
 95struct auth_ops {
 96	char *	name;
 97	struct module *owner;
 98	int	flavour;
 99	int	(*accept)(struct svc_rqst *rq, __be32 *authp);
100	int	(*release)(struct svc_rqst *rq);
101	void	(*domain_release)(struct auth_domain *);
102	int	(*set_client)(struct svc_rqst *rq);
103};
104
105#define	SVC_GARBAGE	1
106#define	SVC_SYSERR	2
107#define	SVC_VALID	3
108#define	SVC_NEGATIVE	4
109#define	SVC_OK		5
110#define	SVC_DROP	6
111#define	SVC_DENIED	7
112#define	SVC_PENDING	8
113#define	SVC_COMPLETE	9
114
115
116extern int	svc_authenticate(struct svc_rqst *rqstp, __be32 *authp);
117extern int	svc_authorise(struct svc_rqst *rqstp);
118extern int	svc_set_client(struct svc_rqst *rqstp);
119extern int	svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops);
120extern void	svc_auth_unregister(rpc_authflavor_t flavor);
121
122extern struct auth_domain *unix_domain_find(char *name);
123extern void auth_domain_put(struct auth_domain *item);
124extern int auth_unix_add_addr(struct in6_addr *addr, struct auth_domain *dom);
125extern struct auth_domain *auth_domain_lookup(char *name, struct auth_domain *new);
126extern struct auth_domain *auth_domain_find(char *name);
127extern struct auth_domain *auth_unix_lookup(struct in6_addr *addr);
128extern int auth_unix_forget_old(struct auth_domain *dom);
129extern void svcauth_unix_purge(void);
130extern void svcauth_unix_info_release(void *);
131extern int svcauth_unix_set_client(struct svc_rqst *rqstp);
132
133static inline unsigned long hash_str(char *name, int bits)
134{
135	unsigned long hash = 0;
136	unsigned long l = 0;
137	int len = 0;
138	unsigned char c;
139	do {
140		if (unlikely(!(c = *name++))) {
141			c = (char)len; len = -1;
142		}
143		l = (l << 8) | c;
144		len++;
145		if ((len & (BITS_PER_LONG/8-1))==0)
146			hash = hash_long(hash^l, BITS_PER_LONG);
147	} while (len);
148	return hash >> (BITS_PER_LONG - bits);
149}
150
151static inline unsigned long hash_mem(char *buf, int length, int bits)
152{
153	unsigned long hash = 0;
154	unsigned long l = 0;
155	int len = 0;
156	unsigned char c;
157	do {
158		if (len == length) {
159			c = (char)len; len = -1;
160		} else
161			c = *buf++;
162		l = (l << 8) | c;
163		len++;
164		if ((len & (BITS_PER_LONG/8-1))==0)
165			hash = hash_long(hash^l, BITS_PER_LONG);
166	} while (len);
167	return hash >> (BITS_PER_LONG - bits);
168}
169
170#endif /* __KERNEL__ */
171
172#endif /* _LINUX_SUNRPC_SVCAUTH_H_ */