xref: /freebsd/crypto/heimdal/lib/roken/inet_ntop.c (revision 1e413cf93298b5b97441a21d9a50fdcd0ee9945e)
1 /*
2  * Copyright (c) 1999 - 2001 Kungliga Tekniska H�gskolan
3  * (Royal Institute of Technology, Stockholm, Sweden).
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * 3. Neither the name of the Institute nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifdef HAVE_CONFIG_H
35 #include <config.h>
36 RCSID("$Id: inet_ntop.c,v 1.5 2001/04/04 23:58:01 assar Exp $");
37 #endif
38 
39 #include <roken.h>
40 
41 /*
42  *
43  */
44 
45 static const char *
46 inet_ntop_v4 (const void *src, char *dst, size_t size)
47 {
48     const char digits[] = "0123456789";
49     int i;
50     struct in_addr *addr = (struct in_addr *)src;
51     u_long a = ntohl(addr->s_addr);
52     const char *orig_dst = dst;
53 
54     if (size < INET_ADDRSTRLEN) {
55 	errno = ENOSPC;
56 	return NULL;
57     }
58     for (i = 0; i < 4; ++i) {
59 	int n = (a >> (24 - i * 8)) & 0xFF;
60 	int non_zerop = 0;
61 
62 	if (non_zerop || n / 100 > 0) {
63 	    *dst++ = digits[n / 100];
64 	    n %= 100;
65 	    non_zerop = 1;
66 	}
67 	if (non_zerop || n / 10 > 0) {
68 	    *dst++ = digits[n / 10];
69 	    n %= 10;
70 	    non_zerop = 1;
71 	}
72 	*dst++ = digits[n];
73 	if (i != 3)
74 	    *dst++ = '.';
75     }
76     *dst++ = '\0';
77     return orig_dst;
78 }
79 
80 #ifdef HAVE_IPV6
81 static const char *
82 inet_ntop_v6 (const void *src, char *dst, size_t size)
83 {
84     const char xdigits[] = "0123456789abcdef";
85     int i;
86     const struct in6_addr *addr = (struct in6_addr *)src;
87     const u_char *ptr = addr->s6_addr;
88     const char *orig_dst = dst;
89 
90     if (size < INET6_ADDRSTRLEN) {
91 	errno = ENOSPC;
92 	return NULL;
93     }
94     for (i = 0; i < 8; ++i) {
95 	int non_zerop = 0;
96 
97 	if (non_zerop || (ptr[0] >> 4)) {
98 	    *dst++ = xdigits[ptr[0] >> 4];
99 	    non_zerop = 1;
100 	}
101 	if (non_zerop || (ptr[0] & 0x0F)) {
102 	    *dst++ = xdigits[ptr[0] & 0x0F];
103 	    non_zerop = 1;
104 	}
105 	if (non_zerop || (ptr[1] >> 4)) {
106 	    *dst++ = xdigits[ptr[1] >> 4];
107 	    non_zerop = 1;
108 	}
109 	*dst++ = xdigits[ptr[1] & 0x0F];
110 	if (i != 7)
111 	    *dst++ = ':';
112 	ptr += 2;
113     }
114     *dst++ = '\0';
115     return orig_dst;
116 }
117 #endif /* HAVE_IPV6 */
118 
119 const char *
120 inet_ntop(int af, const void *src, char *dst, size_t size)
121 {
122     switch (af) {
123     case AF_INET :
124 	return inet_ntop_v4 (src, dst, size);
125 #ifdef HAVE_IPV6
126     case AF_INET6 :
127 	return inet_ntop_v6 (src, dst, size);
128 #endif
129     default :
130 	errno = EAFNOSUPPORT;
131 	return NULL;
132     }
133 }
134