summaryrefslogtreecommitdiffstats
path: root/net/sunrpc/pmap_clnt.c
blob: c04609d3476a986e630097998a6eeecb76551870 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
/*
 * linux/net/sunrpc/pmap_clnt.c
 *
 * In-kernel RPC portmapper client.
 *
 * Portmapper supports version 2 of the rpcbind protocol (RFC 1833).
 *
 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
 */

#include <linux/types.h>
#include <linux/socket.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/uio.h>
#include <linux/in.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/sched.h>

#ifdef RPC_DEBUG
# define RPCDBG_FACILITY	RPCDBG_PMAP
#endif

#define PMAP_SET		1
#define PMAP_UNSET		2
#define PMAP_GETPORT		3

struct portmap_args {
	u32			pm_prog;
	u32			pm_vers;
	u32			pm_prot;
	unsigned short		pm_port;
	struct rpc_xprt *	pm_xprt;
};

static struct rpc_procinfo	pmap_procedures[];
static struct rpc_clnt *	pmap_create(char *, struct sockaddr_in *, int, int);
static void			pmap_getport_done(struct rpc_task *, void *);
static struct rpc_program	pmap_program;

static void pmap_getport_prepare(struct rpc_task *task, void *calldata)
{
	struct portmap_args *map = calldata;
	struct rpc_message msg = {
		.rpc_proc	= &pmap_procedures[PMAP_GETPORT],
		.rpc_argp	= map,
		.rpc_resp	= &map->pm_port,
	};

	rpc_call_setup(task, &msg, 0);
}

static inline struct portmap_args *pmap_map_alloc(void)
{
	return kmalloc(sizeof(struct portmap_args), GFP_NOFS);
}

static inline void pmap_map_free(struct portmap_args *map)
{
	kfree(map);
}

static void pmap_map_release(void *data)
{
	pmap_map_free(data);
}

static const struct rpc_call_ops pmap_getport_ops = {
	.rpc_call_prepare	= pmap_getport_prepare,
	.rpc_call_done		= pmap_getport_done,
	.rpc_release		= pmap_map_release,
};

static inline void pmap_wake_portmap_waiters(struct rpc_xprt *xprt, int status)
{
	xprt_clear_binding(xprt);
	rpc_wake_up_status(&xprt->binding, status);
}

/**
 * rpc_getport - obtain the port for a given RPC service on a given host
 * @task: task that is waiting for portmapper request
 *
 * This one can be called for an ongoing RPC request, and can be used in
 * an async (rpciod) context.
 */
void rpc_getport(struct rpc_task *task)
{
	struct rpc_clnt *clnt = task->tk_client;
	struct rpc_xprt *xprt = task->tk_xprt;
	struct sockaddr_in addr;
	struct portmap_args *map;
	struct rpc_clnt	*pmap_clnt;
	struct rpc_task *child;
	int status;

	dprintk("RPC: %4d rpc_getport(%s, %u, %u, %d)\n",
			task->tk_pid, clnt->cl_server,
			clnt->cl_prog, clnt->cl_vers, xprt->prot);

	/* Autobind on cloned rpc clients is discouraged */
	BUG_ON(clnt->cl_parent != clnt);

	if (xprt_test_and_set_binding(xprt)) {
		task->tk_status = -EACCES;	/* tell caller to check again */
		rpc_sleep_on(&xprt->binding, task, NULL, NULL);
		return;
	}

	/* Someone else may have bound if we slept */
	status = 0;
	if (xprt_bound(xprt))
		goto bailout_nofree;

	status = -ENOMEM;
	map = pmap_map_alloc();
	if (!map)
		goto bailout_nofree;
	map->pm_prog = clnt->cl_prog;
	map->pm_vers = clnt->cl_vers;
	map->pm_prot = xprt->prot;
	map->pm_port = 0;
	map->pm_xprt = xprt_get(xprt);

	rpc_peeraddr(clnt, (struct sockaddr *) &addr, sizeof(addr));
	pmap_clnt = pmap_create(clnt->cl_server, &addr, map->pm_prot, 0);
	status = PTR_ERR(pmap_clnt);
	if (IS_ERR(pmap_clnt))
		goto bailout;

	status = -EIO;
	child = rpc_run_task(pmap_clnt, RPC_TASK_ASYNC, &pmap_getport_ops, map);
	if (IS_ERR(child))
		goto bailout;
	rpc_release_task(child);

	rpc_sleep_on(&xprt->binding, task, NULL, NULL);

	task->tk_xprt->stat.bind_count++;
	return;

bailout:
	pmap_map_free(map);
	xprt_put(xprt);
bailout_nofree:
	task->tk_status = status;
	pmap_wake_portmap_waiters(xprt, status);
}

#ifdef CONFIG_ROOT_NFS
/**
 * rpc_getport_external - obtain the port for a given RPC service on a given host
 * @sin: address of remote peer
 * @prog: RPC program number to bind
 * @vers: RPC version number to bind
 * @prot: transport protocol to use to make this request
 *
 * This one is called from outside the RPC client in a synchronous task context.
 */
int rpc_getport_external(struct sockaddr_in *sin, __u32 prog, __u32 vers, int prot)
{
	struct portmap_args map = {
		.pm_prog	= prog,
		.pm_vers	= vers,
		.pm_prot	= prot,
		.pm_port	= 0
	};
	struct rpc_message msg = {
		.rpc_proc	= &pmap_procedures[PMAP_GETPORT],
		.rpc_argp	= &map,
		.rpc_resp	= &map.pm_port,
	};
	struct rpc_clnt	*pmap_clnt;
	char		hostname[32];
	int		status;

	dprintk("RPC:      rpc_getport_external(%u.%u.%u.%u, %u, %u, %d)\n",
			NIPQUAD(sin->sin_addr.s_addr), prog, vers, prot);

	sprintf(hostname, "%u.%u.%u.%u", NIPQUAD(sin->sin_addr.s_addr));
	pmap_clnt = pmap_create(hostname, sin, prot, 0);
	if (IS_ERR(pmap_clnt))
		return PTR_ERR(pmap_clnt);

	/* Setup the call info struct */
	status = rpc_call_sync(pmap_clnt, &msg, 0);

	if (status >= 0) {
		if (map.pm_port != 0)
			return map.pm_port;
		status = -EACCES;
	}
	return status;
}
#endif

/*
 * Portmapper child task invokes this callback via tk_exit.
 */
static void pmap_getport_done(struct rpc_task *child, void *data)
{
	struct portmap_args *map = data;
	struct rpc_xprt *xprt = map->pm_xprt;
	int status = child->tk_status;

	if (status < 0) {
		/* Portmapper not available */
		xprt->ops->set_port(xprt, 0);
	} else if (map->pm_port == 0) {
		/* Requested RPC service wasn't registered */
		xprt->ops->set_port(xprt, 0);
		status = -EACCES;
	} else {
		/* Succeeded */
		xprt->ops->set_port(xprt, map->pm_port);
		xprt_set_bound(xprt);
		status = 0;
	}

	dprintk("RPC: %4d pmap_getport_done(status %d, port %u)\n",
			child->tk_pid, status, map->pm_port);

	pmap_wake_portmap_waiters(xprt, status);
	xprt_put(xprt);
}

/**
 * rpc_register - set or unset a port registration with the local portmapper
 * @prog: RPC program number to bind
 * @vers: RPC version number to bind
 * @prot: transport protocol to use to make this request
 * @port: port value to register
 * @okay: result code
 *
 * port == 0 means unregister, port != 0 means register.
 */
int rpc_register(u32 prog, u32 vers, int prot, unsigned short port, int *okay)
{
	struct sockaddr_in	sin = {
		.sin_family	= AF_INET,
		.sin_addr.s_addr = htonl(INADDR_LOOPBACK),
	};
	struct portmap_args	map = {
		.pm_prog	= prog,
		.pm_vers	= vers,
		.pm_prot	= prot,
		.pm_port	= port,
	};
	struct rpc_message msg = {
		.rpc_proc	= &pmap_procedures[port ? PMAP_SET : PMAP_UNSET],
		.rpc_argp	= &map,
		.rpc_resp	= okay,
	};
	struct rpc_clnt		*pmap_clnt;
	int error = 0;

	dprintk("RPC: registering (%u, %u, %d, %u) with portmapper.\n",
			prog, vers, prot, port);

	pmap_clnt = pmap_create("localhost", &sin, IPPROTO_UDP, 1);
	if (IS_ERR(pmap_clnt)) {
		error = PTR_ERR(pmap_clnt);
		dprintk("RPC: couldn't create pmap client. Error = %d\n", error);
		return error;
	}

	error = rpc_call_sync(pmap_clnt, &msg, 0);

	if (error < 0) {
		printk(KERN_WARNING
			"RPC: failed to contact portmap (errno %d).\n",
			error);
	}
	dprintk("RPC: registration status %d/%d\n", error, *okay);

	/* Client deleted automatically because cl_oneshot == 1 */
	return error;
}

static struct rpc_clnt *pmap_create(char *hostname, struct sockaddr_in *srvaddr, int proto, int privileged)
{
	struct rpc_create_args args = {
		.protocol	= proto,
		.address	= (struct sockaddr *)srvaddr,
		.addrsize	= sizeof(*srvaddr),
		.servername	= hostname,
		.program	= &pmap_program,
		.version	= RPC_PMAP_VERSION,
		.authflavor	= RPC_AUTH_UNIX,
		.flags		= (RPC_CLNT_CREATE_ONESHOT |
				   RPC_CLNT_CREATE_NOPING),
	};

	srvaddr->sin_port = htons(RPC_PMAP_PORT);
	if (!privileged)
		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
	return rpc_create(&args);
}

/*
 * XDR encode/decode functions for PMAP
 */
static int xdr_encode_mapping(struct rpc_rqst *req, u32 *p, struct portmap_args *map)
{
	dprintk("RPC: xdr_encode_mapping(%u, %u, %u, %u)\n",
		map->pm_prog, map->pm_vers, map->pm_prot, map->pm_port);
	*p++ = htonl(map->pm_prog);
	*p++ = htonl(map->pm_vers);
	*p++ = htonl(map->pm_prot);
	*p++ = htonl(map->pm_port);

	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
	return 0;
}

static int xdr_decode_port(struct rpc_rqst *req, u32 *p, unsigned short *portp)
{
	*portp = (unsigned short) ntohl(*p++);
	return 0;
}

static int xdr_decode_bool(struct rpc_rqst *req, u32 *p, unsigned int *boolp)
{
	*boolp = (unsigned int) ntohl(*p++);
	return 0;
}

static struct rpc_procinfo	pmap_procedures[] = {
[PMAP_SET] = {
	  .p_proc		= PMAP_SET,
	  .p_encode		= (kxdrproc_t) xdr_encode_mapping,	
	  .p_decode		= (kxdrproc_t) xdr_decode_bool,
	  .p_bufsiz		= 4,
	  .p_count		= 1,
	  .p_statidx		= PMAP_SET,
	  .p_name		= "SET",
	},
[PMAP_UNSET] = {
	  .p_proc		= PMAP_UNSET,
	  .p_encode		= (kxdrproc_t) xdr_encode_mapping,	
	  .p_decode		= (kxdrproc_t) xdr_decode_bool,
	  .p_bufsiz		= 4,
	  .p_count		= 1,
	  .p_statidx		= PMAP_UNSET,
	  .p_name		= "UNSET",
	},
[PMAP_GETPORT] = {
	  .p_proc		= PMAP_GETPORT,
	  .p_encode		= (kxdrproc_t) xdr_encode_mapping,
	  .p_decode		= (kxdrproc_t) xdr_decode_port,
	  .p_bufsiz		= 4,
	  .p_count		= 1,
	  .p_statidx		= PMAP_GETPORT,
	  .p_name		= "GETPORT",
	},
};

static struct rpc_version	pmap_version2 = {
	.number		= 2,
	.nrprocs	= 4,
	.procs		= pmap_procedures
};

static struct rpc_version *	pmap_version[] = {
	NULL,
	NULL,
	&pmap_version2
};

static struct rpc_stat		pmap_stats;

static struct rpc_program	pmap_program = {
	.name		= "portmap",
	.number		= RPC_PMAP_PROGRAM,
	.nrvers		= ARRAY_SIZE(pmap_version),
	.version	= pmap_version,
	.stats		= &pmap_stats,
};
OpenPOWER on IntegriCloud