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 #include <config.h>
19
20 #include "netdissect-stdinc.h"
21 #include <stddef.h>
22 #include <string.h>
23
24 #include "netdissect-ctype.h"
25
26 #include "strtoaddr.h"
27
28 #ifndef NS_INADDRSZ
29 #define NS_INADDRSZ 4 /* IPv4 T_A */
30 #endif
31
32 #ifndef NS_IN6ADDRSZ
33 #define NS_IN6ADDRSZ 16 /* IPv6 T_AAAA */
34 #endif
35
36 #ifndef NS_INT16SZ
37 #define NS_INT16SZ 2 /* #/bytes of data in a uint16_t */
38 #endif
39
40 /*%
41 * WARNING: Don't even consider trying to compile this on a system where
42 * sizeof(int) < 4. sizeof(int) > 4 is fine; all the world's not a VAX.
43 */
44
45 /* int
46 * strtoaddr(src, dst)
47 * convert presentation level IPv4 address to network order binary form.
48 * return:
49 * 1 if `src' is a valid input, else 0.
50 * notice:
51 * does not touch `dst' unless it's returning 1.
52 * author:
53 * Paul Vixie, 1996.
54 */
55 int
strtoaddr(const char * src,void * dst)56 strtoaddr(const char *src, void *dst)
57 {
58 uint32_t val;
59 u_int digit;
60 ptrdiff_t n;
61 unsigned char c;
62 u_int parts[4];
63 u_int *pp = parts;
64
65 c = *src;
66 for (;;) {
67 /*
68 * Collect number up to ``.''.
69 * Values are specified as for C:
70 * 0x=hex, 0=octal, isdigit=decimal.
71 */
72 if (!ND_ASCII_ISDIGIT(c))
73 return (0);
74 val = 0;
75 if (c == '0') {
76 c = *++src;
77 if (c == 'x' || c == 'X')
78 return (0);
79 else if (ND_ASCII_ISDIGIT(c) && c != '9')
80 return (0);
81 }
82 for (;;) {
83 if (ND_ASCII_ISDIGIT(c)) {
84 digit = c - '0';
85 val = (val * 10) + digit;
86 c = *++src;
87 } else
88 break;
89 }
90 if (c == '.') {
91 /*
92 * Internet format:
93 * a.b.c.d
94 * a.b.c (with c treated as 16 bits)
95 * a.b (with b treated as 24 bits)
96 * a (with a treated as 32 bits)
97 */
98 if (pp >= parts + 3)
99 return (0);
100 *pp++ = val;
101 c = *++src;
102 } else
103 break;
104 }
105 /*
106 * Check for trailing characters.
107 */
108 if (c != '\0' && c != ' ' && c != '\t')
109 return (0);
110 /*
111 * Find the number of parts specified.
112 * It must be 4; we only support dotted quads, we don't
113 * support shorthand.
114 */
115 n = pp - parts + 1;
116 if (n != 4)
117 return (0);
118 /*
119 * parts[0-2] were set to the first 3 parts of the address;
120 * val was set to the 4th part.
121 *
122 * Check if any part is bigger than 255.
123 */
124 if ((parts[0] | parts[1] | parts[2] | val) > 0xff)
125 return (0);
126 /*
127 * Add the other three parts to val.
128 */
129 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
130 if (dst) {
131 val = htonl(val);
132 memcpy(dst, &val, NS_INADDRSZ);
133 }
134 return (1);
135 }
136
137 /* int
138 * strtoaddr6(src, dst)
139 * convert presentation level IPv6 address to network order binary form.
140 * return:
141 * 1 if `src' is a valid [RFC1884 2.2] address, else 0.
142 * notice:
143 * (1) does not touch `dst' unless it's returning 1.
144 * (2) :: in a full address is silently ignored.
145 * credit:
146 * inspired by Mark Andrews.
147 * author:
148 * Paul Vixie, 1996.
149 */
150 int
strtoaddr6(const char * src,void * dst)151 strtoaddr6(const char *src, void *dst)
152 {
153 static const char xdigits_l[] = "0123456789abcdef",
154 xdigits_u[] = "0123456789ABCDEF";
155 u_char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
156 const char *xdigits, *curtok;
157 int ch, seen_xdigits;
158 u_int val;
159
160 memset((tp = tmp), '\0', NS_IN6ADDRSZ);
161 endp = tp + NS_IN6ADDRSZ;
162 colonp = NULL;
163 /* Leading :: requires some special handling. */
164 if (*src == ':')
165 if (*++src != ':')
166 return (0);
167 curtok = src;
168 seen_xdigits = 0;
169 val = 0;
170 while ((ch = *src++) != '\0') {
171 const char *pch;
172
173 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
174 pch = strchr((xdigits = xdigits_u), ch);
175 if (pch != NULL) {
176 val <<= 4;
177 val |= (int)(pch - xdigits);
178 if (++seen_xdigits > 4)
179 return (0);
180 continue;
181 }
182 if (ch == ':') {
183 curtok = src;
184 if (!seen_xdigits) {
185 if (colonp)
186 return (0);
187 colonp = tp;
188 continue;
189 } else if (*src == '\0')
190 return (0);
191 if (tp + NS_INT16SZ > endp)
192 return (0);
193 *tp++ = (u_char) (val >> 8) & 0xff;
194 *tp++ = (u_char) val & 0xff;
195 seen_xdigits = 0;
196 val = 0;
197 continue;
198 }
199 if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
200 strtoaddr(curtok, tp) > 0) {
201 tp += NS_INADDRSZ;
202 seen_xdigits = 0;
203 break; /*%< '\\0' was seen by strtoaddr(). */
204 }
205 return (0);
206 }
207 if (seen_xdigits) {
208 if (tp + NS_INT16SZ > endp)
209 return (0);
210 *tp++ = (u_char) (val >> 8) & 0xff;
211 *tp++ = (u_char) val & 0xff;
212 }
213 if (colonp != NULL) {
214 /*
215 * Since some memmove()'s erroneously fail to handle
216 * overlapping regions, we'll do the shift by hand.
217 */
218 const ptrdiff_t n = tp - colonp;
219 int i;
220
221 if (tp == endp)
222 return (0);
223 for (i = 1; i <= n; i++) {
224 endp[- i] = colonp[n - i];
225 colonp[n - i] = 0;
226 }
227 tp = endp;
228 }
229 if (tp != endp)
230 return (0);
231 memcpy(dst, tmp, NS_IN6ADDRSZ);
232 return (1);
233 }
234