summaryrefslogtreecommitdiffstats
path: root/strtoaddr.c
blob: c6f79d9a6ec4475ecdf2847a6a6daecd81ef9d17 (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
/*
 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
 * Copyright (c) 1996,1999 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 ISC DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC 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.
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "netdissect-stdinc.h"
#include <stddef.h>
#include <string.h>

#include "netdissect-ctype.h"

#include "strtoaddr.h"

#ifndef NS_INADDRSZ
#define NS_INADDRSZ	4	/* IPv4 T_A */
#endif

#ifndef NS_IN6ADDRSZ
#define NS_IN6ADDRSZ	16	/* IPv6 T_AAAA */
#endif

#ifndef NS_INT16SZ
#define NS_INT16SZ	2	/* #/bytes of data in a uint16_t */
#endif

/*%
 * WARNING: Don't even consider trying to compile this on a system where
 * sizeof(int) < 4.  sizeof(int) > 4 is fine; all the world's not a VAX.
 */

/* int
 * strtoaddr(src, dst)
 *	convert presentation level IPv4 address to network order binary form.
 * return:
 *	1 if `src' is a valid input, else 0.
 * notice:
 *	does not touch `dst' unless it's returning 1.
 * author:
 *	Paul Vixie, 1996.
 */
int
strtoaddr(const char *src, void *dst)
{
	uint32_t val;
	u_int digit;
	ptrdiff_t n;
	unsigned char c;
	u_int parts[4];
	u_int *pp = parts;

	c = *src;
	for (;;) {
		/*
		 * Collect number up to ``.''.
		 * Values are specified as for C:
		 * 0x=hex, 0=octal, isdigit=decimal.
		 */
		if (!ND_ASCII_ISDIGIT(c))
			return (0);
		val = 0;
		if (c == '0') {
			c = *++src;
			if (c == 'x' || c == 'X')
				return (0);
			else if (ND_ASCII_ISDIGIT(c) && c != '9')
				return (0);
		}
		for (;;) {
			if (ND_ASCII_ISDIGIT(c)) {
				digit = c - '0';
				val = (val * 10) + digit;
				c = *++src;
			} else
				break;
		}
		if (c == '.') {
			/*
			 * Internet format:
			 *	a.b.c.d
			 *	a.b.c	(with c treated as 16 bits)
			 *	a.b	(with b treated as 24 bits)
			 *	a	(with a treated as 32 bits)
			 */
			if (pp >= parts + 3)
				return (0);
			*pp++ = val;
			c = *++src;
		} else
			break;
	}
	/*
	 * Check for trailing characters.
	 */
	if (c != '\0' && c != ' ' && c != '\t')
		return (0);
	/*
	 * Find the number of parts specified.
	 * It must be 4; we only support dotted quads, we don't
	 * support shorthand.
	 */
	n = pp - parts + 1;
	if (n != 4)
		return (0);
	/*
	 * parts[0-2] were set to the first 3 parts of the address;
	 * val was set to the 4th part.
	 *
	 * Check if any part is bigger than 255.
	 */
	if ((parts[0] | parts[1] | parts[2] | val) > 0xff)
		return (0);
	/*
	 * Add the other three parts to val.
	 */
	val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
	if (dst) {
		val = htonl(val);
		memcpy(dst, &val, NS_INADDRSZ);
	}
	return (1);
}

/* int
 * strtoaddr6(src, dst)
 *	convert presentation level IPv6 address to network order binary form.
 * return:
 *	1 if `src' is a valid [RFC1884 2.2] address, else 0.
 * notice:
 *	(1) does not touch `dst' unless it's returning 1.
 *	(2) :: in a full address is silently ignored.
 * credit:
 *	inspired by Mark Andrews.
 * author:
 *	Paul Vixie, 1996.
 */
int
strtoaddr6(const char *src, void *dst)
{
	static const char xdigits_l[] = "0123456789abcdef",
			  xdigits_u[] = "0123456789ABCDEF";
	u_char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
	const char *xdigits, *curtok;
	int ch, seen_xdigits;
	u_int val;

	memset((tp = tmp), '\0', NS_IN6ADDRSZ);
	endp = tp + NS_IN6ADDRSZ;
	colonp = NULL;
	/* Leading :: requires some special handling. */
	if (*src == ':')
		if (*++src != ':')
			return (0);
	curtok = src;
	seen_xdigits = 0;
	val = 0;
	while ((ch = *src++) != '\0') {
		const char *pch;

		if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
			pch = strchr((xdigits = xdigits_u), ch);
		if (pch != NULL) {
			val <<= 4;
			val |= (int)(pch - xdigits);
			if (++seen_xdigits > 4)
				return (0);
			continue;
		}
		if (ch == ':') {
			curtok = src;
			if (!seen_xdigits) {
				if (colonp)
					return (0);
				colonp = tp;
				continue;
			} else if (*src == '\0')
				return (0);
			if (tp + NS_INT16SZ > endp)
				return (0);
			*tp++ = (u_char) (val >> 8) & 0xff;
			*tp++ = (u_char) val & 0xff;
			seen_xdigits = 0;
			val = 0;
			continue;
		}
		if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
		    strtoaddr(curtok, tp) > 0) {
			tp += NS_INADDRSZ;
			seen_xdigits = 0;
			break;	/*%< '\\0' was seen by strtoaddr(). */
		}
		return (0);
	}
	if (seen_xdigits) {
		if (tp + NS_INT16SZ > endp)
			return (0);
		*tp++ = (u_char) (val >> 8) & 0xff;
		*tp++ = (u_char) val & 0xff;
	}
	if (colonp != NULL) {
		/*
		 * Since some memmove()'s erroneously fail to handle
		 * overlapping regions, we'll do the shift by hand.
		 */
		const ptrdiff_t n = tp - colonp;
		int i;

		if (tp == endp)
			return (0);
		for (i = 1; i <= n; i++) {
			endp[- i] = colonp[n - i];
			colonp[n - i] = 0;
		}
		tp = endp;
	}
	if (tp != endp)
		return (0);
	memcpy(dst, tmp, NS_IN6ADDRSZ);
	return (1);
}