about summary refs log tree commit diff
path: root/resolv/inet_net_pton.c
blob: d3f1350312cd77a11e2ef5edcc69a9e3f50a4a47 (plain) (blame)
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
/*
 * Copyright (c) 1996 by Internet Software Consortium.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static const char rcsid[] = "$Id$";
#endif

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#ifdef SPRINTF_CHAR
# define SPRINTF(x) strlen(sprintf/**/x)
#else
# define SPRINTF(x) ((size_t)sprintf x)
#endif

static int	inet_net_pton_ipv4 __P((const char *src, u_char *dst,
					size_t size));

/*
 * static int
 * inet_net_pton(af, src, dst, size)
 *	convert network number from presentation to network format.
 *	accepts hex octets, hex strings, decimal octets, and /CIDR.
 *	"size" is in bytes and describes "dst".
 * return:
 *	number of bits, either imputed classfully or specified with /CIDR,
 *	or -1 if some failure occurred (check errno).  ENOENT means it was
 *	not a valid network specification.
 * author:
 *	Paul Vixie (ISC), June 1996
 */
int
inet_net_pton(af, src, dst, size)
	int af;
	const char *src;
	void *dst;
	size_t size;
{
	switch (af) {
	case AF_INET:
		return (inet_net_pton_ipv4(src, dst, size));
	default:
		__set_errno (EAFNOSUPPORT);
		return (-1);
	}
}

/*
 * static int
 * inet_net_pton_ipv4(src, dst, size)
 *	convert IPv4 network number from presentation to network format.
 *	accepts hex octets, hex strings, decimal octets, and /CIDR.
 *	"size" is in bytes and describes "dst".
 * return:
 *	number of bits, either imputed classfully or specified with /CIDR,
 *	or -1 if some failure occurred (check errno).  ENOENT means it was
 *	not an IPv4 network specification.
 * note:
 *	network byte order assumed.  this means 192.5.5.240/28 has
 *	0x11110000 in its fourth octet.
 * author:
 *	Paul Vixie (ISC), June 1996
 */
static int
inet_net_pton_ipv4(src, dst, size)
	const char *src;
	u_char *dst;
	size_t size;
{
	static const char
		xdigits[] = "0123456789abcdef",
		digits[] = "0123456789";
	int n, ch, tmp, dirty, bits;
	const u_char *odst = dst;

	ch = *src++;
	if (ch == '0' && (src[0] == 'x' || src[0] == 'X')
	    && isascii(src[1]) && isxdigit(src[1])) {
		/* Hexadecimal: Eat nybble string. */
		if (size <= 0)
			goto emsgsize;
		*dst = 0, dirty = 0;
		src++;	/* skip x or X. */
		while ((ch = *src++) != '\0' &&
		       isascii(ch) && isxdigit(ch)) {
			ch = _tolower(ch);
			n = strchr(xdigits, ch) - xdigits;
			assert(n >= 0 && n <= 15);
			*dst |= n;
			if (!dirty++)
				*dst <<= 4;
			else if (size-- > 0)
				*++dst = 0, dirty = 0;
			else
				goto emsgsize;
		}
		if (dirty)
			size--;
	} else if (isascii(ch) && isdigit(ch)) {
		/* Decimal: eat dotted digit string. */
		for (;;) {
			tmp = 0;
			do {
				n = strchr(digits, ch) - digits;
				assert(n >= 0 && n <= 9);
				tmp *= 10;
				tmp += n;
				if (tmp > 255)
					goto enoent;
			} while ((ch = *src++) != '\0' &&
				 isascii(ch) && isdigit(ch));
			if (size-- <= 0)
				goto emsgsize;
			*dst++ = (u_char) tmp;
			if (ch == '\0' || ch == '/')
				break;
			if (ch != '.')
				goto enoent;
			ch = *src++;
			if (!isascii(ch) || !isdigit(ch))
				goto enoent;
		}
	} else
		goto enoent;

	bits = -1;
	if (ch == '/' && isascii(src[0]) && isdigit(src[0]) && dst > odst) {
		/* CIDR width specifier.  Nothing can follow it. */
		ch = *src++;	/* Skip over the /. */
		bits = 0;
		do {
			n = strchr(digits, ch) - digits;
			assert(n >= 0 && n <= 9);
			bits *= 10;
			bits += n;
		} while ((ch = *src++) != '\0' &&
			 isascii(ch) && isdigit(ch));
		if (ch != '\0')
			goto enoent;
		if (bits > 32)
			goto emsgsize;
	}

	/* Firey death and destruction unless we prefetched EOS. */
	if (ch != '\0')
		goto enoent;

	/* If nothing was written to the destination, we found no address. */
	if (dst == odst)
		goto enoent;
	/* If no CIDR spec was given, infer width from net class. */
	if (bits == -1) {
		if (*odst >= 240)	/* Class E */
			bits = 32;
		else if (*odst >= 224)	/* Class D */
			bits = 4;
		else if (*odst >= 192)	/* Class C */
			bits = 24;
		else if (*odst >= 128)	/* Class B */
			bits = 16;
		else			/* Class A */
			bits = 8;
		/* If imputed mask is narrower than specified octets, widen. */
		if (bits >= 8 && bits < ((dst - odst) * 8))
			bits = (dst - odst) * 8;
	}
	/* Extend network to cover the actual mask. */
	while (bits > ((dst - odst) * 8)) {
		if (size-- <= 0)
			goto emsgsize;
		*dst++ = '\0';
	}
	return (bits);

 enoent:
	__set_errno (ENOENT);
	return (-1);

 emsgsize:
	__set_errno (EMSGSIZE);
	return (-1);
}