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 *
30 * Currently, the nfs server uses the auth_domain to stand
31 * for the "client" listed in /etc/exports.
32 *
33 * More generally, a domain might represent a group of clients using
34 * a common mechanism for authentication and having a common mapping
35 * between local identity (uid) and network identity. All clients
36 * in a domain have similar general access rights. Each domain can
37 * contain multiple principals which will have different specific right
38 * based on normal Discretionary Access Control.
39 *
40 * A domain is created by an authentication flavour module based on name
41 * only. Userspace then fills in detail on demand.
42 *
43 * In the case of auth_unix and auth_null, the auth_domain is also
44 * associated with entries in another cache representing the mapping
45 * of ip addresses to the given client.
46 */
47 struct auth_domain {
48 struct kref ref;
49 struct hlist_node hash;
50 char *name;
51 struct auth_ops *flavour;
52 };
53
54 /*
55 * Each authentication flavour registers an auth_ops
56 * structure.
57 * name is simply the name.
58 * flavour gives the auth flavour. It determines where the flavour is registered
59 * accept() is given a request and should verify it.
60 * It should inspect the authenticator and verifier, and possibly the data.
61 * If there is a problem with the authentication *authp should be set.
62 * The return value of accept() can indicate:
63 * OK - authorised. client and credential are set in rqstp.
64 * reqbuf points to arguments
65 * resbuf points to good place for results. verfier
66 * is (probably) already in place. Certainly space is
67 * reserved for it.
68 * DROP - simply drop the request. It may have been deferred
69 * GARBAGE - rpc garbage_args error
70 * SYSERR - rpc system_err error
71 * DENIED - authp holds reason for denial.
72 * COMPLETE - the reply is encoded already and ready to be sent; no
73 * further processing is necessary. (This is used for processing
74 * null procedure calls which are used to set up encryption
75 * contexts.)
76 *
77 * accept is passed the proc number so that it can accept NULL rpc requests
78 * even if it cannot authenticate the client (as is sometimes appropriate).
79 *
80 * release() is given a request after the procedure has been run.
81 * It should sign/encrypt the results if needed
82 * It should return:
83 * OK - the resbuf is ready to be sent
84 * DROP - the reply should be quitely dropped
85 * DENIED - authp holds a reason for MSG_DENIED
86 * SYSERR - rpc system_err
87 *
88 * domain_release()
89 * This call releases a domain.
90 * set_client()
91 * Givens a pending request (struct svc_rqst), finds and assigns
92 * an appropriate 'auth_domain' as the client.
93 */
94 struct auth_ops {
95 char * name;
96 struct module *owner;
97 int flavour;
98 int (*accept)(struct svc_rqst *rq, u32 *authp);
99 int (*release)(struct svc_rqst *rq);
100 void (*domain_release)(struct auth_domain *);
101 int (*set_client)(struct svc_rqst *rq);
102 };
103
104 #define SVC_GARBAGE 1
105 #define SVC_SYSERR 2
106 #define SVC_VALID 3
107 #define SVC_NEGATIVE 4
108 #define SVC_OK 5
109 #define SVC_DROP 6
110 #define SVC_DENIED 7
111 #define SVC_PENDING 8
112 #define SVC_COMPLETE 9
113
114
115 extern int svc_authenticate(struct svc_rqst *rqstp, u32 *authp);
116 extern int svc_authorise(struct svc_rqst *rqstp);
117 extern int svc_set_client(struct svc_rqst *rqstp);
118 extern int svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops);
119 extern void svc_auth_unregister(rpc_authflavor_t flavor);
120
121 extern struct auth_domain *unix_domain_find(char *name);
122 extern void auth_domain_put(struct auth_domain *item);
123 extern int auth_unix_add_addr(struct in_addr addr, struct auth_domain *dom);
124 extern struct auth_domain *auth_domain_lookup(char *name, struct auth_domain *new);
125 extern struct auth_domain *auth_domain_find(char *name);
126 extern struct auth_domain *auth_unix_lookup(struct in_addr addr);
127 extern int auth_unix_forget_old(struct auth_domain *dom);
128 extern void svcauth_unix_purge(void);
129
hash_str(char * name,int bits)130 static inline unsigned long hash_str(char *name, int bits)
131 {
132 unsigned long hash = 0;
133 unsigned long l = 0;
134 int len = 0;
135 unsigned char c;
136 do {
137 if (unlikely(!(c = *name++))) {
138 c = (char)len; len = -1;
139 }
140 l = (l << 8) | c;
141 len++;
142 if ((len & (BITS_PER_LONG/8-1))==0)
143 hash = hash_long(hash^l, BITS_PER_LONG);
144 } while (len);
145 return hash >> (BITS_PER_LONG - bits);
146 }
147
hash_mem(char * buf,int length,int bits)148 static inline unsigned long hash_mem(char *buf, int length, int bits)
149 {
150 unsigned long hash = 0;
151 unsigned long l = 0;
152 int len = 0;
153 unsigned char c;
154 do {
155 if (len == length) {
156 c = (char)len; len = -1;
157 } else
158 c = *buf++;
159 l = (l << 8) | c;
160 len++;
161 if ((len & (BITS_PER_LONG/8-1))==0)
162 hash = hash_long(hash^l, BITS_PER_LONG);
163 } while (len);
164 return hash >> (BITS_PER_LONG - bits);
165 }
166
167 #endif /* __KERNEL__ */
168
169 #endif /* _LINUX_SUNRPC_SVCAUTH_H_ */
170