Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/fs/nfs/callback.c | |
3 | * | |
4 | * Copyright (C) 2004 Trond Myklebust | |
5 | * | |
6 | * NFSv4 callback handling | |
7 | */ | |
8 | ||
1da177e4 LT |
9 | #include <linux/completion.h> |
10 | #include <linux/ip.h> | |
11 | #include <linux/module.h> | |
12 | #include <linux/smp_lock.h> | |
13 | #include <linux/sunrpc/svc.h> | |
14 | #include <linux/sunrpc/svcsock.h> | |
15 | #include <linux/nfs_fs.h> | |
353ab6e9 | 16 | #include <linux/mutex.h> |
83144186 | 17 | #include <linux/freezer.h> |
a277e33c | 18 | #include <linux/kthread.h> |
945b34a7 | 19 | #include <linux/sunrpc/svcauth_gss.h> |
a43cde94 RL |
20 | #if defined(CONFIG_NFS_V4_1) |
21 | #include <linux/sunrpc/bc_xprt.h> | |
22 | #endif | |
14c85021 ACM |
23 | |
24 | #include <net/inet_sock.h> | |
25 | ||
4ce79717 | 26 | #include "nfs4_fs.h" |
1da177e4 | 27 | #include "callback.h" |
24c8dbbb | 28 | #include "internal.h" |
1da177e4 LT |
29 | |
30 | #define NFSDBG_FACILITY NFSDBG_CALLBACK | |
31 | ||
32 | struct nfs_callback_data { | |
33 | unsigned int users; | |
a43cde94 | 34 | struct svc_serv *serv; |
5afc597c | 35 | struct svc_rqst *rqst; |
a277e33c | 36 | struct task_struct *task; |
1da177e4 LT |
37 | }; |
38 | ||
e82dc22d | 39 | static struct nfs_callback_data nfs_callback_info[NFS4_MAX_MINOR_VERSION + 1]; |
353ab6e9 | 40 | static DEFINE_MUTEX(nfs_callback_mutex); |
1da177e4 LT |
41 | static struct svc_program nfs4_callback_program; |
42 | ||
a72b4422 | 43 | unsigned int nfs_callback_set_tcpport; |
1da177e4 | 44 | unsigned short nfs_callback_tcpport; |
f738f517 | 45 | unsigned short nfs_callback_tcpport6; |
c140aa91 | 46 | #define NFS_CALLBACK_MAXPORTNR (65535U) |
7d4e2747 | 47 | |
c140aa91 | 48 | static int param_set_portnr(const char *val, struct kernel_param *kp) |
7d4e2747 | 49 | { |
c140aa91 TM |
50 | unsigned long num; |
51 | int ret; | |
52 | ||
53 | if (!val) | |
54 | return -EINVAL; | |
55 | ret = strict_strtoul(val, 0, &num); | |
56 | if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR) | |
7d4e2747 | 57 | return -EINVAL; |
c140aa91 | 58 | *((unsigned int *)kp->arg) = num; |
7d4e2747 DH |
59 | return 0; |
60 | } | |
61 | ||
c140aa91 TM |
62 | static int param_get_portnr(char *buffer, struct kernel_param *kp) |
63 | { | |
64 | return param_get_uint(buffer, kp); | |
65 | } | |
66 | #define param_check_portnr(name, p) __param_check(name, p, unsigned int); | |
67 | ||
68 | module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644); | |
1da177e4 LT |
69 | |
70 | /* | |
e82dc22d | 71 | * This is the NFSv4 callback kernel thread. |
1da177e4 | 72 | */ |
a277e33c | 73 | static int |
71468513 | 74 | nfs4_callback_svc(void *vrqstp) |
1da177e4 | 75 | { |
06e02d66 | 76 | int err, preverr = 0; |
a277e33c | 77 | struct svc_rqst *rqstp = vrqstp; |
1da177e4 | 78 | |
83144186 | 79 | set_freezable(); |
1da177e4 | 80 | |
a277e33c JL |
81 | /* |
82 | * FIXME: do we really need to run this under the BKL? If so, please | |
83 | * add a comment about what it's intended to protect. | |
84 | */ | |
85 | lock_kernel(); | |
86 | while (!kthread_should_stop()) { | |
1da177e4 LT |
87 | /* |
88 | * Listen for a request on the socket | |
89 | */ | |
6fb2b47f | 90 | err = svc_recv(rqstp, MAX_SCHEDULE_TIMEOUT); |
06e02d66 JL |
91 | if (err == -EAGAIN || err == -EINTR) { |
92 | preverr = err; | |
1da177e4 | 93 | continue; |
06e02d66 | 94 | } |
1da177e4 | 95 | if (err < 0) { |
06e02d66 JL |
96 | if (err != preverr) { |
97 | printk(KERN_WARNING "%s: unexpected error " | |
98 | "from svc_recv (%d)\n", __func__, err); | |
99 | preverr = err; | |
100 | } | |
101 | schedule_timeout_uninterruptible(HZ); | |
102 | continue; | |
1da177e4 | 103 | } |
06e02d66 | 104 | preverr = err; |
6fb2b47f | 105 | svc_process(rqstp); |
1da177e4 | 106 | } |
1da177e4 | 107 | unlock_kernel(); |
a277e33c | 108 | return 0; |
1da177e4 LT |
109 | } |
110 | ||
111 | /* | |
71468513 | 112 | * Prepare to bring up the NFSv4 callback service |
1da177e4 | 113 | */ |
71468513 BH |
114 | struct svc_rqst * |
115 | nfs4_callback_up(struct svc_serv *serv) | |
1da177e4 | 116 | { |
71468513 | 117 | int ret; |
482fb94e | 118 | |
26298caa | 119 | ret = svc_create_xprt(serv, "tcp", PF_INET, |
9652ada3 | 120 | nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS); |
482fb94e | 121 | if (ret <= 0) |
8e60029f | 122 | goto out_err; |
482fb94e | 123 | nfs_callback_tcpport = ret; |
18de9735 | 124 | dprintk("NFS: Callback listener port = %u (af %u)\n", |
26298caa | 125 | nfs_callback_tcpport, PF_INET); |
482fb94e | 126 | |
f738f517 CL |
127 | #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) |
128 | ret = svc_create_xprt(serv, "tcp", PF_INET6, | |
129 | nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS); | |
130 | if (ret > 0) { | |
131 | nfs_callback_tcpport6 = ret; | |
132 | dprintk("NFS: Callback listener port = %u (af %u)\n", | |
133 | nfs_callback_tcpport6, PF_INET6); | |
18fc3164 CL |
134 | } else if (ret == -EAFNOSUPPORT) |
135 | ret = 0; | |
136 | else | |
f738f517 CL |
137 | goto out_err; |
138 | #endif /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */ | |
139 | ||
71468513 BH |
140 | return svc_prepare_thread(serv, &serv->sv_pools[0]); |
141 | ||
142 | out_err: | |
143 | if (ret == 0) | |
144 | ret = -ENOMEM; | |
145 | return ERR_PTR(ret); | |
146 | } | |
147 | ||
a43cde94 RL |
148 | #if defined(CONFIG_NFS_V4_1) |
149 | /* | |
150 | * The callback service for NFSv4.1 callbacks | |
151 | */ | |
152 | static int | |
153 | nfs41_callback_svc(void *vrqstp) | |
154 | { | |
155 | struct svc_rqst *rqstp = vrqstp; | |
156 | struct svc_serv *serv = rqstp->rq_server; | |
157 | struct rpc_rqst *req; | |
158 | int error; | |
159 | DEFINE_WAIT(wq); | |
160 | ||
161 | set_freezable(); | |
162 | ||
163 | /* | |
164 | * FIXME: do we really need to run this under the BKL? If so, please | |
165 | * add a comment about what it's intended to protect. | |
166 | */ | |
167 | lock_kernel(); | |
168 | while (!kthread_should_stop()) { | |
169 | prepare_to_wait(&serv->sv_cb_waitq, &wq, TASK_INTERRUPTIBLE); | |
170 | spin_lock_bh(&serv->sv_cb_lock); | |
171 | if (!list_empty(&serv->sv_cb_list)) { | |
172 | req = list_first_entry(&serv->sv_cb_list, | |
173 | struct rpc_rqst, rq_bc_list); | |
174 | list_del(&req->rq_bc_list); | |
175 | spin_unlock_bh(&serv->sv_cb_lock); | |
176 | dprintk("Invoking bc_svc_process()\n"); | |
177 | error = bc_svc_process(serv, req, rqstp); | |
178 | dprintk("bc_svc_process() returned w/ error code= %d\n", | |
179 | error); | |
180 | } else { | |
181 | spin_unlock_bh(&serv->sv_cb_lock); | |
182 | schedule(); | |
183 | } | |
184 | finish_wait(&serv->sv_cb_waitq, &wq); | |
185 | } | |
186 | unlock_kernel(); | |
a43cde94 RL |
187 | return 0; |
188 | } | |
189 | ||
190 | /* | |
191 | * Bring up the NFSv4.1 callback service | |
192 | */ | |
193 | struct svc_rqst * | |
194 | nfs41_callback_up(struct svc_serv *serv, struct rpc_xprt *xprt) | |
195 | { | |
8f975242 BH |
196 | struct svc_xprt *bc_xprt; |
197 | struct svc_rqst *rqstp = ERR_PTR(-ENOMEM); | |
198 | ||
199 | dprintk("--> %s\n", __func__); | |
200 | /* Create a svc_sock for the service */ | |
201 | bc_xprt = svc_sock_create(serv, xprt->prot); | |
202 | if (!bc_xprt) | |
203 | goto out; | |
204 | ||
a43cde94 RL |
205 | /* |
206 | * Save the svc_serv in the transport so that it can | |
207 | * be referenced when the session backchannel is initialized | |
208 | */ | |
8f975242 | 209 | serv->bc_xprt = bc_xprt; |
a43cde94 RL |
210 | xprt->bc_serv = serv; |
211 | ||
212 | INIT_LIST_HEAD(&serv->sv_cb_list); | |
213 | spin_lock_init(&serv->sv_cb_lock); | |
214 | init_waitqueue_head(&serv->sv_cb_waitq); | |
8f975242 BH |
215 | rqstp = svc_prepare_thread(serv, &serv->sv_pools[0]); |
216 | if (IS_ERR(rqstp)) | |
217 | svc_sock_destroy(bc_xprt); | |
218 | out: | |
219 | dprintk("--> %s return %p\n", __func__, rqstp); | |
220 | return rqstp; | |
a43cde94 RL |
221 | } |
222 | ||
223 | static inline int nfs_minorversion_callback_svc_setup(u32 minorversion, | |
224 | struct svc_serv *serv, struct rpc_xprt *xprt, | |
225 | struct svc_rqst **rqstpp, int (**callback_svc)(void *vrqstp)) | |
226 | { | |
227 | if (minorversion) { | |
228 | *rqstpp = nfs41_callback_up(serv, xprt); | |
229 | *callback_svc = nfs41_callback_svc; | |
230 | } | |
231 | return minorversion; | |
232 | } | |
233 | ||
234 | static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt, | |
235 | struct nfs_callback_data *cb_info) | |
236 | { | |
237 | if (minorversion) | |
238 | xprt->bc_serv = cb_info->serv; | |
239 | } | |
240 | #else | |
241 | static inline int nfs_minorversion_callback_svc_setup(u32 minorversion, | |
242 | struct svc_serv *serv, struct rpc_xprt *xprt, | |
243 | struct svc_rqst **rqstpp, int (**callback_svc)(void *vrqstp)) | |
244 | { | |
245 | return 0; | |
246 | } | |
247 | ||
248 | static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt, | |
249 | struct nfs_callback_data *cb_info) | |
250 | { | |
251 | } | |
252 | #endif /* CONFIG_NFS_V4_1 */ | |
253 | ||
71468513 BH |
254 | /* |
255 | * Bring up the callback thread if it is not already up. | |
256 | */ | |
257 | int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt) | |
258 | { | |
259 | struct svc_serv *serv = NULL; | |
260 | struct svc_rqst *rqstp; | |
261 | int (*callback_svc)(void *vrqstp); | |
e82dc22d | 262 | struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion]; |
71468513 BH |
263 | char svc_name[12]; |
264 | int ret = 0; | |
a43cde94 | 265 | int minorversion_setup; |
71468513 BH |
266 | |
267 | mutex_lock(&nfs_callback_mutex); | |
e82dc22d AA |
268 | if (cb_info->users++ || cb_info->task != NULL) { |
269 | nfs_callback_bc_serv(minorversion, xprt, cb_info); | |
71468513 | 270 | goto out; |
a43cde94 | 271 | } |
71468513 BH |
272 | serv = svc_create(&nfs4_callback_program, NFS4_CALLBACK_BUFSIZE, NULL); |
273 | if (!serv) { | |
274 | ret = -ENOMEM; | |
275 | goto out_err; | |
276 | } | |
277 | ||
a43cde94 RL |
278 | minorversion_setup = nfs_minorversion_callback_svc_setup(minorversion, |
279 | serv, xprt, &rqstp, &callback_svc); | |
280 | if (!minorversion_setup) { | |
281 | /* v4.0 callback setup */ | |
71468513 BH |
282 | rqstp = nfs4_callback_up(serv); |
283 | callback_svc = nfs4_callback_svc; | |
71468513 BH |
284 | } |
285 | ||
286 | if (IS_ERR(rqstp)) { | |
287 | ret = PTR_ERR(rqstp); | |
8e60029f | 288 | goto out_err; |
a277e33c JL |
289 | } |
290 | ||
291 | svc_sock_update_bufs(serv); | |
a277e33c | 292 | |
71468513 | 293 | sprintf(svc_name, "nfsv4.%u-svc", minorversion); |
e82dc22d AA |
294 | cb_info->serv = serv; |
295 | cb_info->rqst = rqstp; | |
296 | cb_info->task = kthread_run(callback_svc, cb_info->rqst, svc_name); | |
297 | if (IS_ERR(cb_info->task)) { | |
298 | ret = PTR_ERR(cb_info->task); | |
299 | svc_exit_thread(cb_info->rqst); | |
300 | cb_info->rqst = NULL; | |
301 | cb_info->task = NULL; | |
a277e33c JL |
302 | goto out_err; |
303 | } | |
1da177e4 | 304 | out: |
8e60029f JL |
305 | /* |
306 | * svc_create creates the svc_serv with sv_nrthreads == 1, and then | |
a277e33c | 307 | * svc_prepare_thread increments that. So we need to call svc_destroy |
8e60029f JL |
308 | * on both success and failure so that the refcount is 1 when the |
309 | * thread exits. | |
310 | */ | |
311 | if (serv) | |
312 | svc_destroy(serv); | |
353ab6e9 | 313 | mutex_unlock(&nfs_callback_mutex); |
1da177e4 | 314 | return ret; |
8e60029f | 315 | out_err: |
18de9735 CL |
316 | dprintk("NFS: Couldn't create callback socket or server thread; " |
317 | "err = %d\n", ret); | |
e82dc22d | 318 | cb_info->users--; |
1da177e4 LT |
319 | goto out; |
320 | } | |
321 | ||
322 | /* | |
5afc597c | 323 | * Kill the callback thread if it's no longer being used. |
1da177e4 | 324 | */ |
e82dc22d | 325 | void nfs_callback_down(int minorversion) |
1da177e4 | 326 | { |
e82dc22d AA |
327 | struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion]; |
328 | ||
353ab6e9 | 329 | mutex_lock(&nfs_callback_mutex); |
e82dc22d AA |
330 | cb_info->users--; |
331 | if (cb_info->users == 0 && cb_info->task != NULL) { | |
332 | kthread_stop(cb_info->task); | |
333 | svc_exit_thread(cb_info->rqst); | |
334 | cb_info->serv = NULL; | |
335 | cb_info->rqst = NULL; | |
336 | cb_info->task = NULL; | |
5afc597c | 337 | } |
353ab6e9 | 338 | mutex_unlock(&nfs_callback_mutex); |
1da177e4 LT |
339 | } |
340 | ||
945b34a7 OK |
341 | static int check_gss_callback_principal(struct nfs_client *clp, |
342 | struct svc_rqst *rqstp) | |
343 | { | |
344 | struct rpc_clnt *r = clp->cl_rpcclient; | |
345 | char *p = svc_gss_principal(rqstp); | |
346 | ||
347 | /* | |
348 | * It might just be a normal user principal, in which case | |
349 | * userspace won't bother to tell us the name at all. | |
350 | */ | |
351 | if (p == NULL) | |
352 | return SVC_DENIED; | |
353 | ||
354 | /* Expect a GSS_C_NT_HOSTBASED_NAME like "nfs@serverhostname" */ | |
355 | ||
356 | if (memcmp(p, "nfs@", 4) != 0) | |
357 | return SVC_DENIED; | |
358 | p += 4; | |
359 | if (strcmp(p, r->cl_server) != 0) | |
360 | return SVC_DENIED; | |
361 | return SVC_OK; | |
362 | } | |
363 | ||
1da177e4 LT |
364 | static int nfs_callback_authenticate(struct svc_rqst *rqstp) |
365 | { | |
adfa6f98 | 366 | struct nfs_client *clp; |
5216a8e7 | 367 | RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]); |
945b34a7 | 368 | int ret = SVC_OK; |
1da177e4 LT |
369 | |
370 | /* Don't talk to strangers */ | |
ff052645 | 371 | clp = nfs_find_client(svc_addr(rqstp), 4); |
1da177e4 LT |
372 | if (clp == NULL) |
373 | return SVC_DROP; | |
ad06e4bd | 374 | |
3110ff80 | 375 | dprintk("%s: %s NFSv4 callback!\n", __func__, |
ad06e4bd | 376 | svc_print_addr(rqstp, buf, sizeof(buf))); |
ad06e4bd | 377 | |
1da177e4 LT |
378 | switch (rqstp->rq_authop->flavour) { |
379 | case RPC_AUTH_NULL: | |
380 | if (rqstp->rq_proc != CB_NULL) | |
945b34a7 | 381 | ret = SVC_DENIED; |
1da177e4 LT |
382 | break; |
383 | case RPC_AUTH_UNIX: | |
384 | break; | |
385 | case RPC_AUTH_GSS: | |
945b34a7 OK |
386 | ret = check_gss_callback_principal(clp, rqstp); |
387 | break; | |
1da177e4 | 388 | default: |
945b34a7 | 389 | ret = SVC_DENIED; |
1da177e4 | 390 | } |
945b34a7 OK |
391 | nfs_put_client(clp); |
392 | return ret; | |
1da177e4 LT |
393 | } |
394 | ||
395 | /* | |
396 | * Define NFS4 callback program | |
397 | */ | |
1da177e4 LT |
398 | static struct svc_version *nfs4_callback_version[] = { |
399 | [1] = &nfs4_callback_version1, | |
400 | }; | |
401 | ||
402 | static struct svc_stat nfs4_callback_stats; | |
403 | ||
404 | static struct svc_program nfs4_callback_program = { | |
405 | .pg_prog = NFS4_CALLBACK, /* RPC service number */ | |
406 | .pg_nvers = ARRAY_SIZE(nfs4_callback_version), /* Number of entries */ | |
407 | .pg_vers = nfs4_callback_version, /* version table */ | |
408 | .pg_name = "NFSv4 callback", /* service name */ | |
409 | .pg_class = "nfs", /* authentication class */ | |
410 | .pg_stats = &nfs4_callback_stats, | |
411 | .pg_authenticate = nfs_callback_authenticate, | |
412 | }; |