1*0Sstevel@tonic-gate /* $OpenBSD: inet_ntop.c,v 1.5 2002/08/23 16:27:31 itojun Exp $ */
2*0Sstevel@tonic-gate
3*0Sstevel@tonic-gate /* Copyright (c) 1996 by Internet Software Consortium.
4*0Sstevel@tonic-gate *
5*0Sstevel@tonic-gate * Permission to use, copy, modify, and distribute this software for any
6*0Sstevel@tonic-gate * purpose with or without fee is hereby granted, provided that the above
7*0Sstevel@tonic-gate * copyright notice and this permission notice appear in all copies.
8*0Sstevel@tonic-gate *
9*0Sstevel@tonic-gate * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
10*0Sstevel@tonic-gate * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
11*0Sstevel@tonic-gate * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
12*0Sstevel@tonic-gate * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
13*0Sstevel@tonic-gate * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
14*0Sstevel@tonic-gate * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
15*0Sstevel@tonic-gate * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
16*0Sstevel@tonic-gate * SOFTWARE.
17*0Sstevel@tonic-gate */
18*0Sstevel@tonic-gate
19*0Sstevel@tonic-gate #include "includes.h"
20*0Sstevel@tonic-gate
21*0Sstevel@tonic-gate #ifndef HAVE_INET_NTOP
22*0Sstevel@tonic-gate
23*0Sstevel@tonic-gate #if defined(LIBC_SCCS) && !defined(lint)
24*0Sstevel@tonic-gate #if 0
25*0Sstevel@tonic-gate static char rcsid[] = "$From: inet_ntop.c,v 8.7 1996/08/05 08:41:18 vixie Exp $";
26*0Sstevel@tonic-gate #else
27*0Sstevel@tonic-gate static char rcsid[] = "$OpenBSD: inet_ntop.c,v 1.5 2002/08/23 16:27:31 itojun Exp $";
28*0Sstevel@tonic-gate #endif
29*0Sstevel@tonic-gate #endif /* LIBC_SCCS and not lint */
30*0Sstevel@tonic-gate
31*0Sstevel@tonic-gate #include <sys/param.h>
32*0Sstevel@tonic-gate #include <sys/types.h>
33*0Sstevel@tonic-gate #include <sys/socket.h>
34*0Sstevel@tonic-gate #include "fake-socket.h"
35*0Sstevel@tonic-gate #include <netinet/in.h>
36*0Sstevel@tonic-gate #include <arpa/inet.h>
37*0Sstevel@tonic-gate #ifndef HAVE_CYGWIN
38*0Sstevel@tonic-gate #include <arpa/nameser.h>
39*0Sstevel@tonic-gate #endif
40*0Sstevel@tonic-gate #include <string.h>
41*0Sstevel@tonic-gate #include <errno.h>
42*0Sstevel@tonic-gate #include <stdio.h>
43*0Sstevel@tonic-gate
44*0Sstevel@tonic-gate #ifndef IN6ADDRSZ
45*0Sstevel@tonic-gate #define IN6ADDRSZ 16 /* IPv6 T_AAAA */
46*0Sstevel@tonic-gate #endif
47*0Sstevel@tonic-gate
48*0Sstevel@tonic-gate #ifndef INT16SZ
49*0Sstevel@tonic-gate #define INT16SZ 2 /* for systems without 16-bit ints */
50*0Sstevel@tonic-gate #endif
51*0Sstevel@tonic-gate
52*0Sstevel@tonic-gate /*
53*0Sstevel@tonic-gate * WARNING: Don't even consider trying to compile this on a system where
54*0Sstevel@tonic-gate * sizeof(int) < 4. sizeof(int) > 4 is fine; all the world's not a VAX.
55*0Sstevel@tonic-gate */
56*0Sstevel@tonic-gate
57*0Sstevel@tonic-gate static const char *inet_ntop4(const u_char *src, char *dst, size_t size);
58*0Sstevel@tonic-gate static const char *inet_ntop6(const u_char *src, char *dst, size_t size);
59*0Sstevel@tonic-gate
60*0Sstevel@tonic-gate /* char *
61*0Sstevel@tonic-gate * inet_ntop(af, src, dst, size)
62*0Sstevel@tonic-gate * convert a network format address to presentation format.
63*0Sstevel@tonic-gate * return:
64*0Sstevel@tonic-gate * pointer to presentation format address (`dst'), or NULL (see errno).
65*0Sstevel@tonic-gate * author:
66*0Sstevel@tonic-gate * Paul Vixie, 1996.
67*0Sstevel@tonic-gate */
68*0Sstevel@tonic-gate const char *
inet_ntop(af,src,dst,size)69*0Sstevel@tonic-gate inet_ntop(af, src, dst, size)
70*0Sstevel@tonic-gate int af;
71*0Sstevel@tonic-gate const void *src;
72*0Sstevel@tonic-gate char *dst;
73*0Sstevel@tonic-gate size_t size;
74*0Sstevel@tonic-gate {
75*0Sstevel@tonic-gate switch (af) {
76*0Sstevel@tonic-gate case AF_INET:
77*0Sstevel@tonic-gate return (inet_ntop4(src, dst, size));
78*0Sstevel@tonic-gate case AF_INET6:
79*0Sstevel@tonic-gate return (inet_ntop6(src, dst, size));
80*0Sstevel@tonic-gate default:
81*0Sstevel@tonic-gate errno = EAFNOSUPPORT;
82*0Sstevel@tonic-gate return (NULL);
83*0Sstevel@tonic-gate }
84*0Sstevel@tonic-gate /* NOTREACHED */
85*0Sstevel@tonic-gate }
86*0Sstevel@tonic-gate
87*0Sstevel@tonic-gate /* const char *
88*0Sstevel@tonic-gate * inet_ntop4(src, dst, size)
89*0Sstevel@tonic-gate * format an IPv4 address, more or less like inet_ntoa()
90*0Sstevel@tonic-gate * return:
91*0Sstevel@tonic-gate * `dst' (as a const)
92*0Sstevel@tonic-gate * notes:
93*0Sstevel@tonic-gate * (1) uses no statics
94*0Sstevel@tonic-gate * (2) takes a u_char* not an in_addr as input
95*0Sstevel@tonic-gate * author:
96*0Sstevel@tonic-gate * Paul Vixie, 1996.
97*0Sstevel@tonic-gate */
98*0Sstevel@tonic-gate static const char *
inet_ntop4(src,dst,size)99*0Sstevel@tonic-gate inet_ntop4(src, dst, size)
100*0Sstevel@tonic-gate const u_char *src;
101*0Sstevel@tonic-gate char *dst;
102*0Sstevel@tonic-gate size_t size;
103*0Sstevel@tonic-gate {
104*0Sstevel@tonic-gate static const char fmt[] = "%u.%u.%u.%u";
105*0Sstevel@tonic-gate char tmp[sizeof "255.255.255.255"];
106*0Sstevel@tonic-gate int l;
107*0Sstevel@tonic-gate
108*0Sstevel@tonic-gate l = snprintf(tmp, size, fmt, src[0], src[1], src[2], src[3]);
109*0Sstevel@tonic-gate if (l <= 0 || l >= size) {
110*0Sstevel@tonic-gate errno = ENOSPC;
111*0Sstevel@tonic-gate return (NULL);
112*0Sstevel@tonic-gate }
113*0Sstevel@tonic-gate strlcpy(dst, tmp, size);
114*0Sstevel@tonic-gate return (dst);
115*0Sstevel@tonic-gate }
116*0Sstevel@tonic-gate
117*0Sstevel@tonic-gate /* const char *
118*0Sstevel@tonic-gate * inet_ntop6(src, dst, size)
119*0Sstevel@tonic-gate * convert IPv6 binary address into presentation (printable) format
120*0Sstevel@tonic-gate * author:
121*0Sstevel@tonic-gate * Paul Vixie, 1996.
122*0Sstevel@tonic-gate */
123*0Sstevel@tonic-gate static const char *
inet_ntop6(src,dst,size)124*0Sstevel@tonic-gate inet_ntop6(src, dst, size)
125*0Sstevel@tonic-gate const u_char *src;
126*0Sstevel@tonic-gate char *dst;
127*0Sstevel@tonic-gate size_t size;
128*0Sstevel@tonic-gate {
129*0Sstevel@tonic-gate /*
130*0Sstevel@tonic-gate * Note that int32_t and int16_t need only be "at least" large enough
131*0Sstevel@tonic-gate * to contain a value of the specified size. On some systems, like
132*0Sstevel@tonic-gate * Crays, there is no such thing as an integer variable with 16 bits.
133*0Sstevel@tonic-gate * Keep this in mind if you think this function should have been coded
134*0Sstevel@tonic-gate * to use pointer overlays. All the world's not a VAX.
135*0Sstevel@tonic-gate */
136*0Sstevel@tonic-gate char tmp[sizeof "ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255"];
137*0Sstevel@tonic-gate char *tp, *ep;
138*0Sstevel@tonic-gate struct { int base, len; } best, cur;
139*0Sstevel@tonic-gate u_int words[IN6ADDRSZ / INT16SZ];
140*0Sstevel@tonic-gate int i;
141*0Sstevel@tonic-gate int advance;
142*0Sstevel@tonic-gate
143*0Sstevel@tonic-gate /*
144*0Sstevel@tonic-gate * Preprocess:
145*0Sstevel@tonic-gate * Copy the input (bytewise) array into a wordwise array.
146*0Sstevel@tonic-gate * Find the longest run of 0x00's in src[] for :: shorthanding.
147*0Sstevel@tonic-gate */
148*0Sstevel@tonic-gate memset(words, '\0', sizeof words);
149*0Sstevel@tonic-gate for (i = 0; i < IN6ADDRSZ; i++)
150*0Sstevel@tonic-gate words[i / 2] |= (src[i] << ((1 - (i % 2)) << 3));
151*0Sstevel@tonic-gate best.base = -1;
152*0Sstevel@tonic-gate cur.base = -1;
153*0Sstevel@tonic-gate for (i = 0; i < (IN6ADDRSZ / INT16SZ); i++) {
154*0Sstevel@tonic-gate if (words[i] == 0) {
155*0Sstevel@tonic-gate if (cur.base == -1)
156*0Sstevel@tonic-gate cur.base = i, cur.len = 1;
157*0Sstevel@tonic-gate else
158*0Sstevel@tonic-gate cur.len++;
159*0Sstevel@tonic-gate } else {
160*0Sstevel@tonic-gate if (cur.base != -1) {
161*0Sstevel@tonic-gate if (best.base == -1 || cur.len > best.len)
162*0Sstevel@tonic-gate best = cur;
163*0Sstevel@tonic-gate cur.base = -1;
164*0Sstevel@tonic-gate }
165*0Sstevel@tonic-gate }
166*0Sstevel@tonic-gate }
167*0Sstevel@tonic-gate if (cur.base != -1) {
168*0Sstevel@tonic-gate if (best.base == -1 || cur.len > best.len)
169*0Sstevel@tonic-gate best = cur;
170*0Sstevel@tonic-gate }
171*0Sstevel@tonic-gate if (best.base != -1 && best.len < 2)
172*0Sstevel@tonic-gate best.base = -1;
173*0Sstevel@tonic-gate
174*0Sstevel@tonic-gate /*
175*0Sstevel@tonic-gate * Format the result.
176*0Sstevel@tonic-gate */
177*0Sstevel@tonic-gate tp = tmp;
178*0Sstevel@tonic-gate ep = tmp + sizeof(tmp);
179*0Sstevel@tonic-gate for (i = 0; i < (IN6ADDRSZ / INT16SZ) && tp < ep; i++) {
180*0Sstevel@tonic-gate /* Are we inside the best run of 0x00's? */
181*0Sstevel@tonic-gate if (best.base != -1 && i >= best.base &&
182*0Sstevel@tonic-gate i < (best.base + best.len)) {
183*0Sstevel@tonic-gate if (i == best.base) {
184*0Sstevel@tonic-gate if (tp + 1 >= ep)
185*0Sstevel@tonic-gate return (NULL);
186*0Sstevel@tonic-gate *tp++ = ':';
187*0Sstevel@tonic-gate }
188*0Sstevel@tonic-gate continue;
189*0Sstevel@tonic-gate }
190*0Sstevel@tonic-gate /* Are we following an initial run of 0x00s or any real hex? */
191*0Sstevel@tonic-gate if (i != 0) {
192*0Sstevel@tonic-gate if (tp + 1 >= ep)
193*0Sstevel@tonic-gate return (NULL);
194*0Sstevel@tonic-gate *tp++ = ':';
195*0Sstevel@tonic-gate }
196*0Sstevel@tonic-gate /* Is this address an encapsulated IPv4? */
197*0Sstevel@tonic-gate if (i == 6 && best.base == 0 &&
198*0Sstevel@tonic-gate (best.len == 6 || (best.len == 5 && words[5] == 0xffff))) {
199*0Sstevel@tonic-gate if (!inet_ntop4(src+12, tp, (size_t)(ep - tp)))
200*0Sstevel@tonic-gate return (NULL);
201*0Sstevel@tonic-gate tp += strlen(tp);
202*0Sstevel@tonic-gate break;
203*0Sstevel@tonic-gate }
204*0Sstevel@tonic-gate advance = snprintf(tp, ep - tp, "%x", words[i]);
205*0Sstevel@tonic-gate if (advance <= 0 || advance >= ep - tp)
206*0Sstevel@tonic-gate return (NULL);
207*0Sstevel@tonic-gate tp += advance;
208*0Sstevel@tonic-gate }
209*0Sstevel@tonic-gate /* Was it a trailing run of 0x00's? */
210*0Sstevel@tonic-gate if (best.base != -1 && (best.base + best.len) == (IN6ADDRSZ / INT16SZ)) {
211*0Sstevel@tonic-gate if (tp + 1 >= ep)
212*0Sstevel@tonic-gate return (NULL);
213*0Sstevel@tonic-gate *tp++ = ':';
214*0Sstevel@tonic-gate }
215*0Sstevel@tonic-gate if (tp + 1 >= ep)
216*0Sstevel@tonic-gate return (NULL);
217*0Sstevel@tonic-gate *tp++ = '\0';
218*0Sstevel@tonic-gate
219*0Sstevel@tonic-gate /*
220*0Sstevel@tonic-gate * Check for overflow, copy, and we're done.
221*0Sstevel@tonic-gate */
222*0Sstevel@tonic-gate if ((size_t)(tp - tmp) > size) {
223*0Sstevel@tonic-gate errno = ENOSPC;
224*0Sstevel@tonic-gate return (NULL);
225*0Sstevel@tonic-gate }
226*0Sstevel@tonic-gate strlcpy(dst, tmp, size);
227*0Sstevel@tonic-gate return (dst);
228*0Sstevel@tonic-gate }
229*0Sstevel@tonic-gate
230*0Sstevel@tonic-gate #endif /* !HAVE_INET_NTOP */
231*0Sstevel@tonic-gate
232*0Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI"
233