summaryrefslogtreecommitdiffstats
path: root/net/sunrpc/addr.c
blob: 2e0a6f92e563d7942b3bf7fa17b43e3f44dc9355 (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
/*
 * Copyright 2009, Oracle.  All rights reserved.
 *
 * Convert socket addresses to presentation addresses and universal
 * addresses, and vice versa.
 *
 * Universal addresses are introduced by RFC 1833 and further refined by
 * recent RFCs describing NFSv4.  The universal address format is part
 * of the external (network) interface provided by rpcbind version 3
 * and 4, and by NFSv4.  Such an address is a string containing a
 * presentation format IP address followed by a port number in
 * "hibyte.lobyte" format.
 *
 * IPv6 addresses can also include a scope ID, typically denoted by
 * a '%' followed by a device name or a non-negative integer.  Refer to
 * RFC 4291, Section 2.2 for details on IPv6 presentation formats.
 */

#include <net/ipv6.h>
#include <linux/sunrpc/addr.h>
#include <linux/sunrpc/msg_prot.h>
#include <linux/slab.h>
#include <linux/export.h>

#if IS_ENABLED(CONFIG_IPV6)

static size_t rpc_ntop6_noscopeid(const struct sockaddr *sap,
				  char *buf, const int buflen)
{
	const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
	const struct in6_addr *addr = &sin6->sin6_addr;

	/*
	 * RFC 4291, Section 2.2.2
	 *
	 * Shorthanded ANY address
	 */
	if (ipv6_addr_any(addr))
		return snprintf(buf, buflen, "::");

	/*
	 * RFC 4291, Section 2.2.2
	 *
	 * Shorthanded loopback address
	 */
	if (ipv6_addr_loopback(addr))
		return snprintf(buf, buflen, "::1");

	/*
	 * RFC 4291, Section 2.2.3
	 *
	 * Special presentation address format for mapped v4
	 * addresses.
	 */
	if (ipv6_addr_v4mapped(addr))
		return snprintf(buf, buflen, "::ffff:%pI4",
					&addr->s6_addr32[3]);

	/*
	 * RFC 4291, Section 2.2.1
	 */
	return snprintf(buf, buflen, "%pI6c", addr);
}

static size_t rpc_ntop6(const struct sockaddr *sap,
			char *buf, const size_t buflen)
{
	const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
	char scopebuf[IPV6_SCOPE_ID_LEN];
	size_t len;
	int rc;

	len = rpc_ntop6_noscopeid(sap, buf, buflen);
	if (unlikely(len == 0))
		return len;

	if (!(ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL))
		return len;
	if (sin6->sin6_scope_id == 0)
		return len;

	rc = snprintf(scopebuf, sizeof(scopebuf), "%c%u",
			IPV6_SCOPE_DELIMITER, sin6->sin6_scope_id);
	if (unlikely((size_t)rc > sizeof(scopebuf)))
		return 0;

	len += rc;
	if (unlikely(len > buflen))
		return 0;

	strcat(buf, scopebuf);
	return len;
}

#else	/* !IS_ENABLED(CONFIG_IPV6) */

static size_t rpc_ntop6_noscopeid(const struct sockaddr *sap,
				  char *buf, const int buflen)
{
	return 0;
}

static size_t rpc_ntop6(const struct sockaddr *sap,
			char *buf, const size_t buflen)
{
	return 0;
}

#endif	/* !IS_ENABLED(CONFIG_IPV6) */

static int rpc_ntop4(const struct sockaddr *sap,
		     char *buf, const size_t buflen)
{
	const struct sockaddr_in *sin = (struct sockaddr_in *)sap;

	return snprintf(buf, buflen, "%pI4", &sin->sin_addr);
}

/**
 * rpc_ntop - construct a presentation address in @buf
 * @sap: socket address
 * @buf: construction area
 * @buflen: size of @buf, in bytes
 *
 * Plants a %NUL-terminated string in @buf and returns the length
 * of the string, excluding the %NUL.  Otherwise zero is returned.
 */
size_t rpc_ntop(const struct sockaddr *sap, char *buf, const size_t buflen)
{
	switch (sap->sa_family) {
	case AF_INET:
		return rpc_ntop4(sap, buf, buflen);
	case AF_INET6:
		return rpc_ntop6(sap, buf, buflen);
	}

	return 0;
}
EXPORT_SYMBOL_GPL(rpc_ntop);

static size_t rpc_pton4(const char *buf, const size_t buflen,
			struct sockaddr *sap, const size_t salen)
{
	struct sockaddr_in *sin = (struct sockaddr_in *)sap;
	u8 *addr = (u8 *)&sin->sin_addr.s_addr;

	if (buflen > INET_ADDRSTRLEN || salen < sizeof(struct sockaddr_in))
		return 0;

	memset(sap, 0, sizeof(struct sockaddr_in));

	if (in4_pton(buf, buflen, addr, '\0', NULL) == 0)
		return 0;

	sin->sin_family = AF_INET;
	return sizeof(struct sockaddr_in);
}

#if IS_ENABLED(CONFIG_IPV6)
static int rpc_parse_scope_id(struct net *net, const char *buf,
			      const size_t buflen, const char *delim,
			      struct sockaddr_in6 *sin6)
{
	char *p;
	size_t len;

	if ((buf + buflen) == delim)
		return 1;

	if (*delim != IPV6_SCOPE_DELIMITER)
		return 0;

	if (!(ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL))
		return 0;

	len = (buf + buflen) - delim - 1;
	p = kstrndup(delim + 1, len, GFP_KERNEL);
	if (p) {
		u32 scope_id = 0;
		struct net_device *dev;

		dev = dev_get_by_name(net, p);
		if (dev != NULL) {
			scope_id = dev->ifindex;
			dev_put(dev);
		} else {
			if (kstrtou32(p, 10, &scope_id) == 0) {
				kfree(p);
				return 0;
			}
		}

		kfree(p);

		sin6->sin6_scope_id = scope_id;
		return 1;
	}

	return 0;
}

static size_t rpc_pton6(struct net *net, const char *buf, const size_t buflen,
			struct sockaddr *sap, const size_t salen)
{
	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
	u8 *addr = (u8 *)&sin6->sin6_addr.in6_u;
	const char *delim;

	if (buflen > (INET6_ADDRSTRLEN + IPV6_SCOPE_ID_LEN) ||
	    salen < sizeof(struct sockaddr_in6))
		return 0;

	memset(sap, 0, sizeof(struct sockaddr_in6));

	if (in6_pton(buf, buflen, addr, IPV6_SCOPE_DELIMITER, &delim) == 0)
		return 0;

	if (!rpc_parse_scope_id(net, buf, buflen, delim, sin6))
		return 0;

	sin6->sin6_family = AF_INET6;
	return sizeof(struct sockaddr_in6);
}
#else
static size_t rpc_pton6(struct net *net, const char *buf, const size_t buflen,
			struct sockaddr *sap, const size_t salen)
{
	return 0;
}
#endif

/**
 * rpc_pton - Construct a sockaddr in @sap
 * @net: applicable network namespace
 * @buf: C string containing presentation format IP address
 * @buflen: length of presentation address in bytes
 * @sap: buffer into which to plant socket address
 * @salen: size of buffer in bytes
 *
 * Returns the size of the socket address if successful; otherwise
 * zero is returned.
 *
 * Plants a socket address in @sap and returns the size of the
 * socket address, if successful.  Returns zero if an error
 * occurred.
 */
size_t rpc_pton(struct net *net, const char *buf, const size_t buflen,
		struct sockaddr *sap, const size_t salen)
{
	unsigned int i;

	for (i = 0; i < buflen; i++)
		if (buf[i] == ':')
			return rpc_pton6(net, buf, buflen, sap, salen);
	return rpc_pton4(buf, buflen, sap, salen);
}
EXPORT_SYMBOL_GPL(rpc_pton);

/**
 * rpc_sockaddr2uaddr - Construct a universal address string from @sap.
 * @sap: socket address
 * @gfp_flags: allocation mode
 *
 * Returns a %NUL-terminated string in dynamically allocated memory;
 * otherwise NULL is returned if an error occurred.  Caller must
 * free the returned string.
 */
char *rpc_sockaddr2uaddr(const struct sockaddr *sap, gfp_t gfp_flags)
{
	char portbuf[RPCBIND_MAXUADDRPLEN];
	char addrbuf[RPCBIND_MAXUADDRLEN];
	unsigned short port;

	switch (sap->sa_family) {
	case AF_INET:
		if (rpc_ntop4(sap, addrbuf, sizeof(addrbuf)) == 0)
			return NULL;
		port = ntohs(((struct sockaddr_in *)sap)->sin_port);
		break;
	case AF_INET6:
		if (rpc_ntop6_noscopeid(sap, addrbuf, sizeof(addrbuf)) == 0)
			return NULL;
		port = ntohs(((struct sockaddr_in6 *)sap)->sin6_port);
		break;
	default:
		return NULL;
	}

	if (snprintf(portbuf, sizeof(portbuf),
		     ".%u.%u", port >> 8, port & 0xff) > (int)sizeof(portbuf))
		return NULL;

	if (strlcat(addrbuf, portbuf, sizeof(addrbuf)) > sizeof(addrbuf))
		return NULL;

	return kstrdup(addrbuf, gfp_flags);
}

/**
 * rpc_uaddr2sockaddr - convert a universal address to a socket address.
 * @net: applicable network namespace
 * @uaddr: C string containing universal address to convert
 * @uaddr_len: length of universal address string
 * @sap: buffer into which to plant socket address
 * @salen: size of buffer
 *
 * @uaddr does not have to be '\0'-terminated, but kstrtou8() and
 * rpc_pton() require proper string termination to be successful.
 *
 * Returns the size of the socket address if successful; otherwise
 * zero is returned.
 */
size_t rpc_uaddr2sockaddr(struct net *net, const char *uaddr,
			  const size_t uaddr_len, struct sockaddr *sap,
			  const size_t salen)
{
	char *c, buf[RPCBIND_MAXUADDRLEN + sizeof('\0')];
	u8 portlo, porthi;
	unsigned short port;

	if (uaddr_len > RPCBIND_MAXUADDRLEN)
		return 0;

	memcpy(buf, uaddr, uaddr_len);

	buf[uaddr_len] = '\0';
	c = strrchr(buf, '.');
	if (unlikely(c == NULL))
		return 0;
	if (unlikely(kstrtou8(c + 1, 10, &portlo) != 0))
		return 0;

	*c = '\0';
	c = strrchr(buf, '.');
	if (unlikely(c == NULL))
		return 0;
	if (unlikely(kstrtou8(c + 1, 10, &porthi) != 0))
		return 0;

	port = (unsigned short)((porthi << 8) | portlo);

	*c = '\0';
	if (rpc_pton(net, buf, strlen(buf), sap, salen) == 0)
		return 0;

	switch (sap->sa_family) {
	case AF_INET:
		((struct sockaddr_in *)sap)->sin_port = htons(port);
		return sizeof(struct sockaddr_in);
	case AF_INET6:
		((struct sockaddr_in6 *)sap)->sin6_port = htons(port);
		return sizeof(struct sockaddr_in6);
	}

	return 0;
}
EXPORT_SYMBOL_GPL(rpc_uaddr2sockaddr);
OpenPOWER on IntegriCloud