xref: /xnu-8792.81.2/libkern/net/inet_pton.c (revision 19c3b8c28c31cb8130e034cfb5df6bf9ba342d90)
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 #if defined(LIBC_SCCS) && !defined(lint)
18 static const char rcsid[] = "$Id: inet_pton.c,v 1.3.18.2 2005/07/28 07:38:07 marka Exp $";
19 #endif /* LIBC_SCCS and not lint */
20 
21 #include <string.h>
22 
23 #include <sys/param.h>
24 #include <sys/socket.h>
25 #include <sys/systm.h>
26 
27 #include <netinet/in.h>
28 
29 /*%
30  * WARNING: Don't even consider trying to compile this on a system where
31  * sizeof(int) < 4.  sizeof(int) > 4 is fine; all the world's not a VAX.
32  */
33 
34 static int      inet_pton4(const char *src, u_char *dst);
35 static int      inet_pton6(const char *src, u_char *dst);
36 
37 /* int
38  * inet_pton(af, src, dst)
39  *	convert from presentation format (which usually means ASCII printable)
40  *	to network format (which is usually some kind of binary format).
41  * return:
42  *	1 if the address was valid for the specified address family
43  *	0 if the address wasn't valid (`dst' is untouched in this case)
44  *	-1 if some other error occurred (`dst' is untouched in this case, too)
45  * author:
46  *	Paul Vixie, 1996.
47  */
48 int
inet_pton(int af,const char * src,void * dst)49 inet_pton(int af, const char *src, void *dst)
50 {
51 	switch (af) {
52 	case AF_INET:
53 		return inet_pton4(src, dst);
54 	case AF_INET6:
55 		return inet_pton6(src, dst);
56 	default:
57 		return -1;
58 	}
59 	/* NOTREACHED */
60 }
61 
62 /* int
63  * inet_pton4(src, dst)
64  *	like inet_aton() but without all the hexadecimal and shorthand.
65  * return:
66  *	1 if `src' is a valid dotted quad, else 0.
67  * notice:
68  *	does not touch `dst' unless it's returning 1.
69  * author:
70  *	Paul Vixie, 1996.
71  */
72 static int
inet_pton4(const char * src,u_char * dst)73 inet_pton4(const char *src, u_char *dst)
74 {
75 	static const char digits[] = "0123456789";
76 	int saw_digit, octets, ch;
77 #define NS_INADDRSZ     4
78 	u_char tmp[NS_INADDRSZ], *tp;
79 
80 	saw_digit = 0;
81 	octets = 0;
82 	*(tp = tmp) = 0;
83 	while ((ch = *src++) != '\0') {
84 		const char *pch;
85 
86 		if ((pch = strchr(digits, ch)) != NULL) {
87 			u_int new = *tp * 10 + (u_int)(pch - digits);
88 
89 			if (saw_digit && *tp == 0) {
90 				return 0;
91 			}
92 			if (new > 255) {
93 				return 0;
94 			}
95 			*tp = (u_char)new;
96 			if (!saw_digit) {
97 				if (++octets > 4) {
98 					return 0;
99 				}
100 				saw_digit = 1;
101 			}
102 		} else if (ch == '.' && saw_digit) {
103 			if (octets == 4) {
104 				return 0;
105 			}
106 			*++tp = 0;
107 			saw_digit = 0;
108 		} else {
109 			return 0;
110 		}
111 	}
112 	if (octets < 4) {
113 		return 0;
114 	}
115 	memcpy(dst, tmp, NS_INADDRSZ);
116 	return 1;
117 }
118 
119 /* int
120  * inet_pton6(src, dst)
121  *	convert presentation level address to network order binary form.
122  * return:
123  *	1 if `src' is a valid [RFC1884 2.2] address, else 0.
124  * notice:
125  *	(1) does not touch `dst' unless it's returning 1.
126  *	(2) :: in a full address is silently ignored.
127  * credit:
128  *	inspired by Mark Andrews.
129  * author:
130  *	Paul Vixie, 1996.
131  */
132 static int
inet_pton6(const char * src,u_char * dst)133 inet_pton6(const char *src, u_char *dst)
134 {
135 	static const char xdigits_l[] = "0123456789abcdef",
136 	    xdigits_u[] = "0123456789ABCDEF";
137 #define NS_IN6ADDRSZ    16
138 #define NS_INT16SZ      2
139 	u_char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
140 	const char *xdigits, *curtok;
141 	int ch, seen_xdigits;
142 	u_int val;
143 
144 	memset((tp = tmp), '\0', NS_IN6ADDRSZ);
145 	endp = tp + NS_IN6ADDRSZ;
146 	colonp = NULL;
147 	/* Leading :: requires some special handling. */
148 	if (*src == ':') {
149 		if (*++src != ':') {
150 			return 0;
151 		}
152 	}
153 	curtok = src;
154 	seen_xdigits = 0;
155 	val = 0;
156 	while ((ch = *src++) != '\0') {
157 		const char *pch;
158 
159 		if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL) {
160 			pch = strchr((xdigits = xdigits_u), ch);
161 		}
162 		if (pch != NULL) {
163 			val <<= 4;
164 			val |= (pch - xdigits);
165 			if (++seen_xdigits > 4) {
166 				return 0;
167 			}
168 			continue;
169 		}
170 		if (ch == ':') {
171 			curtok = src;
172 			if (!seen_xdigits) {
173 				if (colonp) {
174 					return 0;
175 				}
176 				colonp = tp;
177 				continue;
178 			} else if (*src == '\0') {
179 				return 0;
180 			}
181 			if (tp + NS_INT16SZ > endp) {
182 				return 0;
183 			}
184 			*tp++ = (u_char) (val >> 8) & 0xff;
185 			*tp++ = (u_char) val & 0xff;
186 			seen_xdigits = 0;
187 			val = 0;
188 			continue;
189 		}
190 		if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
191 		    inet_pton4(curtok, tp) > 0) {
192 			tp += NS_INADDRSZ;
193 			seen_xdigits = 0;
194 			break;  /*%< '\\0' was seen by inet_pton4(). */
195 		}
196 		return 0;
197 	}
198 	if (seen_xdigits) {
199 		if (tp + NS_INT16SZ > endp) {
200 			return 0;
201 		}
202 		*tp++ = (u_char) (val >> 8) & 0xff;
203 		*tp++ = (u_char) val & 0xff;
204 	}
205 	if (colonp != NULL) {
206 		/*
207 		 * Since some memmove()'s erroneously fail to handle
208 		 * overlapping regions, we'll do the shift by hand.
209 		 */
210 		const long n = tp - colonp;
211 		int i;
212 
213 		if (tp == endp) {
214 			return 0;
215 		}
216 		for (i = 1; i <= n; i++) {
217 			endp[-i] = colonp[n - i];
218 			colonp[n - i] = 0;
219 		}
220 		tp = endp;
221 	}
222 	if (tp != endp) {
223 		return 0;
224 	}
225 	memcpy(dst, tmp, NS_IN6ADDRSZ);
226 	return 1;
227 }
228