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 */
57 int
strtoaddr(const char * src,void * dst)58 strtoaddr(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 */
152 int
strtoaddr6(const char * src,void * dst)153 strtoaddr6(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