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 struct 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 */
48 struct 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 */
95 struct 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_CLOSE 7 /* Like SVC_DROP, but request is definitely
112 * lost so if there is a tcp connection, it
113 * should be closed
114 */
115 #define SVC_DENIED 8
116 #define SVC_PENDING 9
117 #define SVC_COMPLETE 10
118
119 struct svc_xprt;
120
121 extern int svc_authenticate(struct svc_rqst *rqstp, __be32 *authp);
122 extern int svc_authorise(struct svc_rqst *rqstp);
123 extern int svc_set_client(struct svc_rqst *rqstp);
124 extern int svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops);
125 extern void svc_auth_unregister(rpc_authflavor_t flavor);
126
127 extern struct auth_domain *unix_domain_find(char *name);
128 extern void auth_domain_put(struct auth_domain *item);
129 extern int auth_unix_add_addr(struct net *net, struct in6_addr *addr, struct auth_domain *dom);
130 extern struct auth_domain *auth_domain_lookup(char *name, struct auth_domain *new);
131 extern struct auth_domain *auth_domain_find(char *name);
132 extern struct auth_domain *auth_unix_lookup(struct net *net, struct in6_addr *addr);
133 extern int auth_unix_forget_old(struct auth_domain *dom);
134 extern void svcauth_unix_purge(void);
135 extern void svcauth_unix_info_release(struct svc_xprt *xpt);
136 extern int svcauth_unix_set_client(struct svc_rqst *rqstp);
137
138 extern int unix_gid_cache_create(struct net *net);
139 extern void unix_gid_cache_destroy(struct net *net);
140
hash_str(char * name,int bits)141 static inline unsigned long hash_str(char *name, int bits)
142 {
143 unsigned long hash = 0;
144 unsigned long l = 0;
145 int len = 0;
146 unsigned char c;
147 do {
148 if (unlikely(!(c = *name++))) {
149 c = (char)len; len = -1;
150 }
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
hash_mem(char * buf,int length,int bits)159 static inline unsigned long hash_mem(char *buf, int length, int bits)
160 {
161 unsigned long hash = 0;
162 unsigned long l = 0;
163 int len = 0;
164 unsigned char c;
165 do {
166 if (len == length) {
167 c = (char)len; len = -1;
168 } else
169 c = *buf++;
170 l = (l << 8) | c;
171 len++;
172 if ((len & (BITS_PER_LONG/8-1))==0)
173 hash = hash_long(hash^l, BITS_PER_LONG);
174 } while (len);
175 return hash >> (BITS_PER_LONG - bits);
176 }
177
178 #endif /* __KERNEL__ */
179
180 #endif /* _LINUX_SUNRPC_SVCAUTH_H_ */
181