1 /* From openssh 4.3p2 compat/inet_ntop.c */
2 /* Copyright (c) 1996 by Internet Software Consortium.
4 * Permission to use, copy, modify, and distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
8 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
9 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
10 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
11 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
12 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
13 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
14 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
18 /* OPENBSD ORIGINAL: lib/libc/net/inet_ntop.c */
20 #include <ldns/config.h>
22 #ifndef HAVE_INET_NTOP
24 #include <sys/param.h>
25 #include <sys/types.h>
26 #ifdef HAVE_SYS_SOCKET_H
27 #include <sys/socket.h>
29 #ifdef HAVE_NETINET_IN_H
30 #include <netinet/in.h>
37 #define IN6ADDRSZ 16 /* IPv6 T_AAAA */
41 #define INT16SZ 2 /* for systems without 16-bit ints */
45 * WARNING: Don't even consider trying to compile this on a system where
46 * sizeof(int) < 4. sizeof(int) > 4 is fine; all the world's not a VAX.
49 static const char *inet_ntop4(const u_char *src, char *dst, size_t size);
50 static const char *inet_ntop6(const u_char *src, char *dst, size_t size);
53 * inet_ntop(af, src, dst, size)
54 * convert a network format address to presentation format.
56 * pointer to presentation format address (`dst'), or NULL (see errno).
61 inet_ntop(int af, const void *src, char *dst, size_t size)
65 return (inet_ntop4(src, dst, size));
67 return (inet_ntop6(src, dst, size));
80 * inet_ntop4(src, dst, size)
81 * format an IPv4 address, more or less like inet_ntoa()
86 * (2) takes a u_char* not an in_addr as input
91 inet_ntop4(const u_char *src, char *dst, size_t size)
93 static const char fmt[] = "%u.%u.%u.%u";
94 char tmp[sizeof "255.255.255.255"];
97 l = snprintf(tmp, size, fmt, src[0], src[1], src[2], src[3]);
98 if (l <= 0 || l >= (int)size) {
102 strlcpy(dst, tmp, size);
107 * inet_ntop6(src, dst, size)
108 * convert IPv6 binary address into presentation (printable) format
113 inet_ntop6(const u_char *src, char *dst, size_t size)
116 * Note that int32_t and int16_t need only be "at least" large enough
117 * to contain a value of the specified size. On some systems, like
118 * Crays, there is no such thing as an integer variable with 16 bits.
119 * Keep this in mind if you think this function should have been coded
120 * to use pointer overlays. All the world's not a VAX.
122 char tmp[sizeof "ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255"];
124 struct { int base, len; } best, cur;
125 u_int words[IN6ADDRSZ / INT16SZ];
131 * Copy the input (bytewise) array into a wordwise array.
132 * Find the longest run of 0x00's in src[] for :: shorthanding.
134 memset(words, '\0', sizeof words);
135 for (i = 0; i < IN6ADDRSZ; i++)
136 words[i / 2] |= (src[i] << ((1 - (i % 2)) << 3));
141 for (i = 0; i < (IN6ADDRSZ / INT16SZ); i++) {
144 cur.base = i, cur.len = 1;
148 if (cur.base != -1) {
149 if (best.base == -1 || cur.len > best.len)
155 if (cur.base != -1) {
156 if (best.base == -1 || cur.len > best.len)
159 if (best.base != -1 && best.len < 2)
166 ep = tmp + sizeof(tmp);
167 for (i = 0; i < (IN6ADDRSZ / INT16SZ) && tp < ep; i++) {
168 /* Are we inside the best run of 0x00's? */
169 if (best.base != -1 && i >= best.base &&
170 i < (best.base + best.len)) {
171 if (i == best.base) {
178 /* Are we following an initial run of 0x00s or any real hex? */
184 /* Is this address an encapsulated IPv4? */
185 if (i == 6 && best.base == 0 &&
186 (best.len == 6 || (best.len == 5 && words[5] == 0xffff))) {
187 if (!inet_ntop4(src+12, tp, (size_t)(ep - tp)))
192 advance = snprintf(tp, ep - tp, "%x", words[i]);
193 if (advance <= 0 || advance >= ep - tp)
197 /* Was it a trailing run of 0x00's? */
198 if (best.base != -1 && (best.base + best.len) == (IN6ADDRSZ / INT16SZ)) {
208 * Check for overflow, copy, and we're done.
210 if ((size_t)(tp - tmp) > size) {
214 strlcpy(dst, tmp, size);
218 #endif /* !HAVE_INET_NTOP */