1 /*
2  * Copyright (c) 1999 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. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *      This product includes software developed by the Kungliga Tekniska
20  *      H�gskolan and its contributors.
21  *
22  * 4. Neither the name of the Institute nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  */
38 
39 /* $Id: inet_ntop.c,v 1.7 2003/11/16 09:36:50 guy Exp $ */
40 
41 #ifndef lint
42 static const char rcsid[] =
43      "@(#) $Header: /tcpdump/master/tcpdump/missing/inet_ntop.c,v 1.7 2003/11/16 09:36:50 guy Exp $";
44 #endif
45 
46 /* we aren't tcpdump :) */
47 #ifdef notdef
48 #include <tcpdump-stdinc.h>
49 #endif
50 
51 #include <stdio.h>
52 #include <sys/types.h>
53 
54 #ifndef WIN32
55 #include <errno.h>
56 #include <sys/socket.h>
57 #include <netinet/in.h>
58 
59 #else   /* WIN32 */
60 #include <time.h>
61 #include <winsock2.h>
62 #ifdef DO_IPV6
63 #include <ws2tcpip.h>
64 #endif  /* DO_IPV6 */
65 #include <windows.h>
66 
67 /* The below are copied from netlib.h */
68 #ifdef errno
69 /* delete the one from stdlib.h  */
70 /*#define errno       (*_errno()) */
71 #undef errno
72 #endif
73 #define errno GetLastError()
74 #define Set_errno(num) SetLastError((num))
75 
76 /* INVALID_SOCKET == INVALID_HANDLE_VALUE == (unsigned int)(~0) */
77 /* SOCKET_ERROR == -1 */
78 #define ENOTSOCK WSAENOTSOCK
79 #define EINTR    WSAEINTR
80 #define ENOBUFS  WSAENOBUFS
81 #define EWOULDBLOCK           WSAEWOULDBLOCK
82 #define EAFNOSUPPORT  WSAEAFNOSUPPORT
83 /* from public\sdk\inc\crt\errno.h */
84 #define ENOSPC          28
85 #endif  /* WIN32 */
86 
87 /*
88  *
89  */
90 
91 #ifndef INET_ADDRSTRLEN
92 #define INET_ADDRSTRLEN    16
93 #endif
94 
95 static const char *
inet_ntop_v4(const void * src,char * dst,size_t size)96 inet_ntop_v4 (const void *src, char *dst, size_t size)
97 {
98     const char digits[] = "0123456789";
99     int i;
100     struct in_addr *addr = (struct in_addr *)src;
101     u_long a = ntohl(addr->s_addr);
102     const char *orig_dst = dst;
103 
104     if (size < INET_ADDRSTRLEN) {
105       Set_errno(ENOSPC);
106       return NULL;
107     }
108     for (i = 0; i < 4; ++i) {
109 	int n = (a >> (24 - i * 8)) & 0xFF;
110 	int non_zerop = 0;
111 
112 	if (non_zerop || n / 100 > 0) {
113 	    *dst++ = digits[n / 100];
114 	    n %= 100;
115 	    non_zerop = 1;
116 	}
117 	if (non_zerop || n / 10 > 0) {
118 	    *dst++ = digits[n / 10];
119 	    n %= 10;
120 	    non_zerop = 1;
121 	}
122 	*dst++ = digits[n];
123 	if (i != 3)
124 	    *dst++ = '.';
125     }
126     *dst++ = '\0';
127     return orig_dst;
128 }
129 
130 const char *
inet_ntop(int af,const void * src,char * dst,size_t size)131 inet_ntop(int af, const void *src, char *dst, size_t size)
132 {
133     switch (af) {
134     case AF_INET :
135 	return inet_ntop_v4 (src, dst, size);
136     default :
137       Set_errno(EAFNOSUPPORT);
138       return NULL;
139     }
140 }
141