summaryrefslogtreecommitdiffstats
path: root/contrib/bind/lib/irs/getnameinfo.c
blob: 7bd30ae5687c0c92188406a9f9b53af7213269d3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
/*
 * Issues to be discussed:
 * - Thread safe-ness must be checked
 * - Return values.  There seems to be no standard for return value (RFC2133)
 *   but INRIA implementation returns EAI_xxx defined for getaddrinfo().
 */

/*
 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    This product includes software developed by WIDE Project and
 *    its contributors.
 * 4. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <port_before.h>

#include <sys/types.h>
#include <sys/socket.h>

#include <netinet/in.h>
#include <arpa/nameser.h>
#include <arpa/inet.h>

#include <netdb.h>
#include <resolv.h>
#include <string.h>

#include <port_after.h>

#define SUCCESS 0
#define ANY 0
#define YES 1
#define NO  0

/*
 * Note that a_off will be dynamically adjusted so that to be consistent
 * with the definition of sockaddr_in{,6}.
 * The value presented below is just a guess.
 */
static struct afd {
	int a_af;
	int a_addrlen;
	int a_socklen;
	int a_off;
} afdl [] = {
	/* first entry is linked last... */
	{PF_INET, sizeof(struct in_addr), sizeof(struct sockaddr_in),
		4 /*XXX*/},
	{PF_INET6, sizeof(struct in6_addr), sizeof(struct sockaddr_in6),
		8 /*XXX*/},
	{0, 0, 0},
};

struct sockinet {
	u_char	si_len;
	u_char	si_family;
	u_short	si_port;
};

#define ENI_NOSOCKET 	0
#define ENI_NOSERVNAME	1
#define ENI_NOHOSTNAME	2
#define ENI_MEMORY	3
#define ENI_SYSTEM	4
#define ENI_FAMILY	5
#define ENI_SALEN	6

int
getnameinfo(sa, salen, host, hostlen, serv, servlen, flags)
	const struct sockaddr *sa;
	size_t salen;
	char *host;
	size_t hostlen;
	char *serv;
	size_t servlen;
	int flags;
{
	struct afd *afd;
	struct servent *sp;
	struct hostent *hp;
	u_short port;
#ifdef HAVE_SA_LEN
	int len;
#endif
	int family, i;
	char *addr, *p;
	u_char pfx;
	static int firsttime = 1;
	static char numserv[512];
	static char numaddr[512];


	/* dynamically adjust a_off */
	if (firsttime) {
		struct afd *p;
		u_char *q;
		struct sockaddr_in sin;
		struct sockaddr_in6 sin6;

		for (p = &afdl[0]; p->a_af; p++) {
			switch (p->a_af) {
			case PF_INET:
				q = (u_char *)&sin.sin_addr.s_addr;
				p->a_off = q - (u_char *)&sin;
				break;
			case PF_INET6:
				q = (u_char *)&sin6.sin6_addr.s6_addr;
				p->a_off = q - (u_char *)&sin6;
				break;
			default:
				break;
			}
		}
		firsttime = 0;
	}

	if (sa == NULL)
		return ENI_NOSOCKET;

#ifdef HAVE_SA_LEN
	len = sa->sa_len;
	if (len != salen) return ENI_SALEN;
#endif
	
	family = sa->sa_family;
	for (i = 0; afdl[i].a_af; i++)
		if (afdl[i].a_af == family) {
			afd = &afdl[i];
			goto found;
		}
	return ENI_FAMILY;
	
 found:
	if (salen != afd->a_socklen) return ENI_SALEN;
	
	port = ((struct sockinet *)sa)->si_port; /* network byte order */
	addr = (char *)sa + afd->a_off;

	if (serv == NULL || servlen == 0) {
		/* what we should do? */
	} else if (flags & NI_NUMERICSERV) {
		snprintf(numserv, strlen(numserv), "%d", ntohs(port));
		if (strlen(numserv) > servlen)
			return ENI_MEMORY;
		strcpy(serv, numserv);
	} else {
		sp = getservbyport(port, (flags & NI_DGRAM) ? "udp" : "tcp");
		if (sp) {
			if (strlen(sp->s_name) > servlen)
				return ENI_MEMORY;
			strcpy(serv, sp->s_name);
		} else
			return ENI_NOSERVNAME;
	}

	switch (sa->sa_family) {
	case AF_INET:
		if (ntohl(*(u_long *)addr) >> IN_CLASSA_NSHIFT == 0)
			flags |= NI_NUMERICHOST;			
		break;
	case AF_INET6:
		pfx = *addr;
		if (pfx == 0 || pfx == 0xfe || pfx == 0xff)
			flags |= NI_NUMERICHOST;
		break;
	}
	if (host == NULL || hostlen == 0) {
		/* what should we do? */
	} else if (flags & NI_NUMERICHOST) {
		if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr))
		    == NULL)
			return ENI_SYSTEM;
		if (strlen(numaddr) > hostlen)
			return ENI_MEMORY;
		strcpy(host, numaddr);
	} else {
		hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af);

		if (hp) {
			if (flags & NI_NOFQDN) {
				p = strchr(hp->h_name, '.');
				if (p) *p = '\0';
			}
			if (strlen(hp->h_name) > hostlen)
				return ENI_MEMORY;
			strcpy(host, hp->h_name);
		} else {
			if (flags & NI_NAMEREQD)
				return ENI_NOHOSTNAME;
			if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr))
			    == NULL)
				return ENI_NOHOSTNAME;
			if (strlen(numaddr) > hostlen)
				return ENI_MEMORY;
			strcpy(host, numaddr);
		}
	}
	return SUCCESS;
}
OpenPOWER on IntegriCloud