1/*
2 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
3 * Copyright (c) 1996,1999 by Internet Software Consortium.
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
15 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18#ifdef HAVE_CONFIG_H
19#include <config.h>
20#endif
21
22#include "netdissect-stdinc.h"
23#include <stddef.h>
24#include <string.h>
25
26#include "netdissect-ctype.h"
27
28#include "strtoaddr.h"
29
30#ifndef NS_INADDRSZ
31#define NS_INADDRSZ	4	/* IPv4 T_A */
32#endif
33
34#ifndef NS_IN6ADDRSZ
35#define NS_IN6ADDRSZ	16	/* IPv6 T_AAAA */
36#endif
37
38#ifndef NS_INT16SZ
39#define NS_INT16SZ	2	/* #/bytes of data in a uint16_t */
40#endif
41
42/*%
43 * WARNING: Don't even consider trying to compile this on a system where
44 * sizeof(int) < 4.  sizeof(int) > 4 is fine; all the world's not a VAX.
45 */
46
47/* int
48 * strtoaddr(src, dst)
49 *	convert presentation level IPv4 address to network order binary form.
50 * return:
51 *	1 if `src' is a valid input, else 0.
52 * notice:
53 *	does not touch `dst' unless it's returning 1.
54 * author:
55 *	Paul Vixie, 1996.
56 */
57int
58strtoaddr(const char *src, void *dst)
59{
60	uint32_t val;
61	u_int digit;
62	ptrdiff_t n;
63	unsigned char c;
64	u_int parts[4];
65	u_int *pp = parts;
66
67	c = *src;
68	for (;;) {
69		/*
70		 * Collect number up to ``.''.
71		 * Values are specified as for C:
72		 * 0x=hex, 0=octal, isdigit=decimal.
73		 */
74		if (!ND_ASCII_ISDIGIT(c))
75			return (0);
76		val = 0;
77		if (c == '0') {
78			c = *++src;
79			if (c == 'x' || c == 'X')
80				return (0);
81			else if (ND_ASCII_ISDIGIT(c) && c != '9')
82				return (0);
83		}
84		for (;;) {
85			if (ND_ASCII_ISDIGIT(c)) {
86				digit = c - '0';
87				val = (val * 10) + digit;
88				c = *++src;
89			} else
90				break;
91		}
92		if (c == '.') {
93			/*
94			 * Internet format:
95			 *	a.b.c.d
96			 *	a.b.c	(with c treated as 16 bits)
97			 *	a.b	(with b treated as 24 bits)
98			 *	a	(with a treated as 32 bits)
99			 */
100			if (pp >= parts + 3)
101				return (0);
102			*pp++ = val;
103			c = *++src;
104		} else
105			break;
106	}
107	/*
108	 * Check for trailing characters.
109	 */
110	if (c != '\0' && c != ' ' && c != '\t')
111		return (0);
112	/*
113	 * Find the number of parts specified.
114	 * It must be 4; we only support dotted quads, we don't
115	 * support shorthand.
116	 */
117	n = pp - parts + 1;
118	if (n != 4)
119		return (0);
120	/*
121	 * parts[0-2] were set to the first 3 parts of the address;
122	 * val was set to the 4th part.
123	 *
124	 * Check if any part is bigger than 255.
125	 */
126	if ((parts[0] | parts[1] | parts[2] | val) > 0xff)
127		return (0);
128	/*
129	 * Add the other three parts to val.
130	 */
131	val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
132	if (dst) {
133		val = htonl(val);
134		memcpy(dst, &val, NS_INADDRSZ);
135	}
136	return (1);
137}
138
139/* int
140 * strtoaddr6(src, dst)
141 *	convert presentation level IPv6 address to network order binary form.
142 * return:
143 *	1 if `src' is a valid [RFC1884 2.2] address, else 0.
144 * notice:
145 *	(1) does not touch `dst' unless it's returning 1.
146 *	(2) :: in a full address is silently ignored.
147 * credit:
148 *	inspired by Mark Andrews.
149 * author:
150 *	Paul Vixie, 1996.
151 */
152int
153strtoaddr6(const char *src, void *dst)
154{
155	static const char xdigits_l[] = "0123456789abcdef",
156			  xdigits_u[] = "0123456789ABCDEF";
157	u_char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
158	const char *xdigits, *curtok;
159	int ch, seen_xdigits;
160	u_int val;
161
162	memset((tp = tmp), '\0', NS_IN6ADDRSZ);
163	endp = tp + NS_IN6ADDRSZ;
164	colonp = NULL;
165	/* Leading :: requires some special handling. */
166	if (*src == ':')
167		if (*++src != ':')
168			return (0);
169	curtok = src;
170	seen_xdigits = 0;
171	val = 0;
172	while ((ch = *src++) != '\0') {
173		const char *pch;
174
175		if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
176			pch = strchr((xdigits = xdigits_u), ch);
177		if (pch != NULL) {
178			val <<= 4;
179			val |= (int)(pch - xdigits);
180			if (++seen_xdigits > 4)
181				return (0);
182			continue;
183		}
184		if (ch == ':') {
185			curtok = src;
186			if (!seen_xdigits) {
187				if (colonp)
188					return (0);
189				colonp = tp;
190				continue;
191			} else if (*src == '\0')
192				return (0);
193			if (tp + NS_INT16SZ > endp)
194				return (0);
195			*tp++ = (u_char) (val >> 8) & 0xff;
196			*tp++ = (u_char) val & 0xff;
197			seen_xdigits = 0;
198			val = 0;
199			continue;
200		}
201		if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
202		    strtoaddr(curtok, tp) > 0) {
203			tp += NS_INADDRSZ;
204			seen_xdigits = 0;
205			break;	/*%< '\\0' was seen by strtoaddr(). */
206		}
207		return (0);
208	}
209	if (seen_xdigits) {
210		if (tp + NS_INT16SZ > endp)
211			return (0);
212		*tp++ = (u_char) (val >> 8) & 0xff;
213		*tp++ = (u_char) val & 0xff;
214	}
215	if (colonp != NULL) {
216		/*
217		 * Since some memmove()'s erroneously fail to handle
218		 * overlapping regions, we'll do the shift by hand.
219		 */
220		const ptrdiff_t n = tp - colonp;
221		int i;
222
223		if (tp == endp)
224			return (0);
225		for (i = 1; i <= n; i++) {
226			endp[- i] = colonp[n - i];
227			colonp[n - i] = 0;
228		}
229		tp = endp;
230	}
231	if (tp != endp)
232		return (0);
233	memcpy(dst, tmp, NS_IN6ADDRSZ);
234	return (1);
235}
236