1 /**
2 * @file ntop.c Network address structure functions
3 *
4 * Copyright (C) 2010 Creytiv.com
5 */
6
7 #define _BSD_SOURCE 1
8 #define _DEFAULT_SOURCE 1
9
10 #ifdef HAVE_INET_NTOP
11 #ifdef WIN32
12 #ifdef _MSC_VER
13 #pragma warning (disable: 4090)
14 #endif
15 #include <windows.h>
16 #else
17 #define __USE_BSD 1 /**< Use BSD code */
18 #include <sys/types.h>
19 #include <sys/socket.h>
20 #include <arpa/inet.h>
21 #define __USE_POSIX 1 /**< Use POSIX code */
22 #include <netdb.h>
23 #endif /* WIN32 */
24 #endif
25 #include <string.h>
26 #include <re_types.h>
27 #include <re_fmt.h>
28 #include <re_mbuf.h>
29 #include <re_sa.h>
30 #include "sa.h"
31
32
33 #define DEBUG_MODULE "net_ntop"
34 #define DEBUG_LEVEL 5
35 #include <re_dbg.h>
36
37
38 #ifndef HAVE_INET_NTOP
39
40
41 #define NS_IN6ADDRSZ 16 /**< IPv6 T_AAAA */
42 #define NS_INT16SZ 2 /**< #/bytes of data in a u_int16_t */
43
44
45 static const char*
inet_ntop4(const u_char * src,char * dst,size_t size)46 inet_ntop4(const u_char *src, char *dst, size_t size)
47 {
48 if (re_snprintf(dst, size, "%u.%u.%u.%u",
49 src[0], src[1], src[2], src[3]) < 0) {
50 errno = ENOSPC;
51 dst[size-1] = 0;
52 return NULL;
53 }
54
55 return dst;
56 }
57
58
59 #ifdef HAVE_INET6
60 /* const char *
61 * inet_ntop6(src, dst, size)
62 * convert IPv6 binary address into presentation (printable) format
63 * author:
64 * Paul Vixie, 1996.
65 */
66
67 static const char *
inet_ntop6(const u_char * src,char * dst,size_t size)68 inet_ntop6(const u_char *src, char *dst, size_t size)
69 {
70 /*
71 * Note that int32_t and int16_t need only be "at least" large enough
72 * to contain a value of the specified size. On some systems, like
73 * Crays, there is no such thing as an integer variable with 16 bits.
74 * Keep this in mind if you think this function should have been coded
75 * to use pointer overlays. All the world's not a VAX.
76 */
77 char tmp[sizeof "ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255"], *tp;
78 struct { int base, len; } best, cur;
79 u_int words[NS_IN6ADDRSZ / NS_INT16SZ];
80 int i;
81
82 /*
83 * Preprocess:
84 * Copy the input (bytewise) array into a wordwise array.
85 * Find the longest run of 0x00's in src[] for :: shorthanding.
86 */
87 memset(words, '\0', sizeof words);
88 for (i = 0; i < NS_IN6ADDRSZ; i++)
89 words[i / 2] |= (src[i] << ((1 - (i % 2)) << 3));
90 best.base = -1;
91 best.len = 0;
92 cur.base = -1;
93 cur.len = 0;
94 for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++) {
95 if (words[i] == 0) {
96 if (cur.base == -1)
97 cur.base = i, cur.len = 1;
98 else
99 cur.len++;
100 }
101 else {
102 if (cur.base != -1) {
103 if (best.base == -1 || cur.len > best.len)
104 best = cur;
105 cur.base = -1;
106 }
107 }
108 }
109 if (cur.base != -1) {
110 if (best.base == -1 || cur.len > best.len)
111 best = cur;
112 }
113 if (best.base != -1 && best.len < 2)
114 best.base = -1;
115
116 /*
117 * Format the result.
118 */
119 tp = tmp;
120 for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++) {
121 /* Are we inside the best run of 0x00's? */
122 if (best.base != -1 && i >= best.base &&
123 i < (best.base + best.len)) {
124 if (i == best.base)
125 *tp++ = ':';
126 continue;
127 }
128 /* Are we following an initial run of 0x00s or any real hex?*/
129 if (i != 0)
130 *tp++ = ':';
131 /* Is this address an encapsulated IPv4? */
132 if (i == 6 && best.base == 0 &&
133 (best.len == 6 || (best.len == 5 && words[5] == 0xffff))) {
134 if (!inet_ntop4(src+12, tp, sizeof tmp - (tp - tmp)))
135 return NULL;
136 tp += strlen(tp);
137 break;
138 }
139 tp += sprintf(tp, "%x", words[i]);
140 }
141 /* Was it a trailing run of 0x00's? */
142 if (best.base != -1 && (best.base + best.len) ==
143 (NS_IN6ADDRSZ / NS_INT16SZ))
144 *tp++ = ':';
145 *tp++ = '\0';
146
147 /*
148 * Check for overflow, copy, and we're done.
149 */
150 if ((size_t)(tp - tmp) > size) {
151 errno = ENOSPC;
152 return NULL;
153 }
154 strcpy(dst, tmp);
155
156 return dst;
157 }
158 #endif
159
160
161 /*
162 * Implementation of inet_ntop()
163 */
164 const char* inet_ntop(int af, const void *src, char *dst, size_t size);
inet_ntop(int af,const void * src,char * dst,size_t size)165 const char* inet_ntop(int af, const void *src, char *dst, size_t size)
166 {
167 switch (af) {
168
169 case AF_INET:
170 return inet_ntop4(src, dst, size);
171
172 #ifdef HAVE_INET6
173 case AF_INET6:
174 return inet_ntop6(src, dst, size);
175 #endif
176
177 default:
178 DEBUG_WARNING("inet_ntop: unknown address family %d\n", af);
179 return NULL;
180 }
181 }
182 #endif
183
184
185 /*
186 * POSIX 1003.1-2001 marks gethostbyaddr() and gethostbyname() obsolescent.
187 * See getaddrinfo(3), getnameinfo(3), gai_strerror(3).
188 */
189
190
191 /**
192 * Convert network address structure to a character string
193 *
194 * @param sa Socket address
195 * @param buf Buffer to return IP address
196 * @param size Size of buffer
197 *
198 * @return 0 if success, otherwise errorcode
199 */
net_inet_ntop(const struct sa * sa,char * buf,int size)200 int net_inet_ntop(const struct sa *sa, char *buf, int size)
201 {
202 if (!sa || !buf || !size)
203 return EINVAL;
204
205 switch (sa->u.sa.sa_family) {
206
207 case AF_INET:
208 inet_ntop(AF_INET, &sa->u.in.sin_addr, buf, size);
209 break;
210
211 #ifdef HAVE_INET6
212 case AF_INET6:
213 inet_ntop(AF_INET6, &sa->u.in6.sin6_addr, buf, size);
214 break;
215 #endif
216
217 default:
218 return EAFNOSUPPORT;
219 }
220
221 return 0;
222 }
223