Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/net/sunrpc/auth_unix.c | |
3 | * | |
4 | * UNIX-style authentication; no AUTH_SHORT support | |
5 | * | |
6 | * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de> | |
7 | */ | |
8 | ||
9 | #include <linux/types.h> | |
10 | #include <linux/sched.h> | |
11 | #include <linux/module.h> | |
1da177e4 LT |
12 | #include <linux/sunrpc/clnt.h> |
13 | #include <linux/sunrpc/auth.h> | |
14 | ||
15 | #define NFS_NGROUPS 16 | |
16 | ||
17 | struct unx_cred { | |
18 | struct rpc_cred uc_base; | |
19 | gid_t uc_gid; | |
20 | gid_t uc_gids[NFS_NGROUPS]; | |
21 | }; | |
22 | #define uc_uid uc_base.cr_uid | |
1da177e4 LT |
23 | |
24 | #define UNX_CRED_EXPIRE (60 * HZ) | |
25 | ||
26 | #define UNX_WRITESLACK (21 + (UNX_MAXNODENAME >> 2)) | |
27 | ||
28 | #ifdef RPC_DEBUG | |
29 | # define RPCDBG_FACILITY RPCDBG_AUTH | |
30 | #endif | |
31 | ||
32 | static struct rpc_auth unix_auth; | |
33 | static struct rpc_cred_cache unix_cred_cache; | |
f1c0a861 | 34 | static const struct rpc_credops unix_credops; |
1da177e4 LT |
35 | |
36 | static struct rpc_auth * | |
37 | unx_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor) | |
38 | { | |
46121cf7 CL |
39 | dprintk("RPC: creating UNIX authenticator for client %p\n", |
40 | clnt); | |
5c9cfc82 | 41 | if (atomic_inc_return(&unix_auth.au_count) == 1) |
1da177e4 LT |
42 | unix_cred_cache.nextgc = jiffies + (unix_cred_cache.expire >> 1); |
43 | return &unix_auth; | |
44 | } | |
45 | ||
46 | static void | |
47 | unx_destroy(struct rpc_auth *auth) | |
48 | { | |
46121cf7 | 49 | dprintk("RPC: destroying UNIX authenticator %p\n", auth); |
3ab9bb72 | 50 | rpcauth_clear_credcache(auth->au_credcache); |
1da177e4 LT |
51 | } |
52 | ||
53 | /* | |
54 | * Lookup AUTH_UNIX creds for current process | |
55 | */ | |
56 | static struct rpc_cred * | |
57 | unx_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) | |
58 | { | |
59 | return rpcauth_lookup_credcache(auth, acred, flags); | |
60 | } | |
61 | ||
62 | static struct rpc_cred * | |
63 | unx_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) | |
64 | { | |
65 | struct unx_cred *cred; | |
66 | int i; | |
67 | ||
46121cf7 CL |
68 | dprintk("RPC: allocating UNIX cred for uid %d gid %d\n", |
69 | acred->uid, acred->gid); | |
1da177e4 | 70 | |
8b3a7005 | 71 | if (!(cred = kmalloc(sizeof(*cred), GFP_KERNEL))) |
1da177e4 LT |
72 | return ERR_PTR(-ENOMEM); |
73 | ||
5fe4755e | 74 | rpcauth_init_cred(&cred->uc_base, acred, auth, &unix_credops); |
fc432dd9 | 75 | cred->uc_base.cr_flags = 1UL << RPCAUTH_CRED_UPTODATE; |
8a317760 | 76 | if (flags & RPCAUTH_LOOKUP_ROOTCREDS) { |
1da177e4 LT |
77 | cred->uc_uid = 0; |
78 | cred->uc_gid = 0; | |
79 | cred->uc_gids[0] = NOGROUP; | |
80 | } else { | |
81 | int groups = acred->group_info->ngroups; | |
82 | if (groups > NFS_NGROUPS) | |
83 | groups = NFS_NGROUPS; | |
84 | ||
1da177e4 LT |
85 | cred->uc_gid = acred->gid; |
86 | for (i = 0; i < groups; i++) | |
87 | cred->uc_gids[i] = GROUP_AT(acred->group_info, i); | |
88 | if (i < NFS_NGROUPS) | |
89 | cred->uc_gids[i] = NOGROUP; | |
90 | } | |
1da177e4 | 91 | |
696e38df | 92 | return &cred->uc_base; |
1da177e4 LT |
93 | } |
94 | ||
95 | static void | |
31be5bf1 | 96 | unx_free_cred(struct unx_cred *unx_cred) |
1da177e4 | 97 | { |
31be5bf1 TM |
98 | dprintk("RPC: unx_free_cred %p\n", unx_cred); |
99 | kfree(unx_cred); | |
100 | } | |
696e38df | 101 | |
31be5bf1 TM |
102 | static void |
103 | unx_free_cred_callback(struct rcu_head *head) | |
104 | { | |
105 | struct unx_cred *unx_cred = container_of(head, struct unx_cred, uc_base.cr_rcu); | |
106 | unx_free_cred(unx_cred); | |
107 | } | |
108 | ||
109 | static void | |
110 | unx_destroy_cred(struct rpc_cred *cred) | |
111 | { | |
112 | call_rcu(&cred->cr_rcu, unx_free_cred_callback); | |
1da177e4 LT |
113 | } |
114 | ||
115 | /* | |
116 | * Match credentials against current process creds. | |
117 | * The root_override argument takes care of cases where the caller may | |
118 | * request root creds (e.g. for NFS swapping). | |
119 | */ | |
120 | static int | |
8a317760 | 121 | unx_match(struct auth_cred *acred, struct rpc_cred *rcred, int flags) |
1da177e4 | 122 | { |
696e38df | 123 | struct unx_cred *cred = container_of(rcred, struct unx_cred, uc_base); |
1da177e4 LT |
124 | int i; |
125 | ||
8a317760 | 126 | if (!(flags & RPCAUTH_LOOKUP_ROOTCREDS)) { |
1da177e4 LT |
127 | int groups; |
128 | ||
129 | if (cred->uc_uid != acred->uid | |
130 | || cred->uc_gid != acred->gid) | |
131 | return 0; | |
132 | ||
133 | groups = acred->group_info->ngroups; | |
134 | if (groups > NFS_NGROUPS) | |
135 | groups = NFS_NGROUPS; | |
136 | for (i = 0; i < groups ; i++) | |
137 | if (cred->uc_gids[i] != GROUP_AT(acred->group_info, i)) | |
138 | return 0; | |
139 | return 1; | |
140 | } | |
141 | return (cred->uc_uid == 0 | |
142 | && cred->uc_gid == 0 | |
143 | && cred->uc_gids[0] == (gid_t) NOGROUP); | |
144 | } | |
145 | ||
146 | /* | |
147 | * Marshal credentials. | |
148 | * Maybe we should keep a cached credential for performance reasons. | |
149 | */ | |
d8ed029d AD |
150 | static __be32 * |
151 | unx_marshal(struct rpc_task *task, __be32 *p) | |
1da177e4 LT |
152 | { |
153 | struct rpc_clnt *clnt = task->tk_client; | |
696e38df | 154 | struct unx_cred *cred = container_of(task->tk_msg.rpc_cred, struct unx_cred, uc_base); |
d8ed029d | 155 | __be32 *base, *hold; |
1da177e4 LT |
156 | int i; |
157 | ||
158 | *p++ = htonl(RPC_AUTH_UNIX); | |
159 | base = p++; | |
160 | *p++ = htonl(jiffies/HZ); | |
161 | ||
162 | /* | |
163 | * Copy the UTS nodename captured when the client was created. | |
164 | */ | |
165 | p = xdr_encode_array(p, clnt->cl_nodename, clnt->cl_nodelen); | |
166 | ||
167 | *p++ = htonl((u32) cred->uc_uid); | |
168 | *p++ = htonl((u32) cred->uc_gid); | |
169 | hold = p++; | |
170 | for (i = 0; i < 16 && cred->uc_gids[i] != (gid_t) NOGROUP; i++) | |
171 | *p++ = htonl((u32) cred->uc_gids[i]); | |
172 | *hold = htonl(p - hold - 1); /* gid array length */ | |
173 | *base = htonl((p - base - 1) << 2); /* cred length */ | |
174 | ||
175 | *p++ = htonl(RPC_AUTH_NULL); | |
176 | *p++ = htonl(0); | |
177 | ||
178 | return p; | |
179 | } | |
180 | ||
181 | /* | |
182 | * Refresh credentials. This is a no-op for AUTH_UNIX | |
183 | */ | |
184 | static int | |
185 | unx_refresh(struct rpc_task *task) | |
186 | { | |
fc432dd9 | 187 | set_bit(RPCAUTH_CRED_UPTODATE, &task->tk_msg.rpc_cred->cr_flags); |
1da177e4 LT |
188 | return 0; |
189 | } | |
190 | ||
d8ed029d AD |
191 | static __be32 * |
192 | unx_validate(struct rpc_task *task, __be32 *p) | |
1da177e4 LT |
193 | { |
194 | rpc_authflavor_t flavor; | |
195 | u32 size; | |
196 | ||
197 | flavor = ntohl(*p++); | |
198 | if (flavor != RPC_AUTH_NULL && | |
199 | flavor != RPC_AUTH_UNIX && | |
200 | flavor != RPC_AUTH_SHORT) { | |
201 | printk("RPC: bad verf flavor: %u\n", flavor); | |
202 | return NULL; | |
203 | } | |
204 | ||
205 | size = ntohl(*p++); | |
206 | if (size > RPC_MAX_AUTH_SIZE) { | |
207 | printk("RPC: giant verf size: %u\n", size); | |
208 | return NULL; | |
209 | } | |
210 | task->tk_auth->au_rslack = (size >> 2) + 2; | |
211 | p += (size >> 2); | |
212 | ||
213 | return p; | |
214 | } | |
215 | ||
9499b434 TM |
216 | void __init rpc_init_authunix(void) |
217 | { | |
218 | spin_lock_init(&unix_cred_cache.lock); | |
219 | } | |
220 | ||
f1c0a861 | 221 | const struct rpc_authops authunix_ops = { |
1da177e4 LT |
222 | .owner = THIS_MODULE, |
223 | .au_flavor = RPC_AUTH_UNIX, | |
224 | #ifdef RPC_DEBUG | |
225 | .au_name = "UNIX", | |
226 | #endif | |
227 | .create = unx_create, | |
228 | .destroy = unx_destroy, | |
229 | .lookup_cred = unx_lookup_cred, | |
230 | .crcreate = unx_create_cred, | |
231 | }; | |
232 | ||
233 | static | |
234 | struct rpc_cred_cache unix_cred_cache = { | |
235 | .expire = UNX_CRED_EXPIRE, | |
236 | }; | |
237 | ||
238 | static | |
239 | struct rpc_auth unix_auth = { | |
240 | .au_cslack = UNX_WRITESLACK, | |
241 | .au_rslack = 2, /* assume AUTH_NULL verf */ | |
242 | .au_ops = &authunix_ops, | |
81039f1f | 243 | .au_flavor = RPC_AUTH_UNIX, |
1da177e4 LT |
244 | .au_count = ATOMIC_INIT(0), |
245 | .au_credcache = &unix_cred_cache, | |
246 | }; | |
247 | ||
248 | static | |
f1c0a861 | 249 | const struct rpc_credops unix_credops = { |
1da177e4 LT |
250 | .cr_name = "AUTH_UNIX", |
251 | .crdestroy = unx_destroy_cred, | |
252 | .crmatch = unx_match, | |
253 | .crmarshal = unx_marshal, | |
254 | .crrefresh = unx_refresh, | |
255 | .crvalidate = unx_validate, | |
256 | }; |