is_ip_address.c revision 298699 
1/*
2 * is_ip_address
3 *
4 */
5
6#ifdef HAVE_CONFIG_H
7# include <config.h>
8#endif
9
10#include "ntp_assert.h"
11#include "ntp_stdlib.h"
12#include "safecast.h"
13
14/* Don't include ISC's version of IPv6 variables and structures */
15#define ISC_IPV6_H 1
16#include <isc/netaddr.h>
17#include <isc/sockaddr.h>
18
19
20/*
21 * Code to tell if we have an IP address
22 * If we have then return the sockaddr structure
23 * and set the return value
24 * see the bind9/getaddresses.c for details
25 */
26int
27is_ip_address(
28	const char *	host,
29	u_short		af,
30	sockaddr_u *	addr
31	)
32{
33	struct in_addr in4;
34	struct addrinfo hints;
35	struct addrinfo *result;
36	struct sockaddr_in6 *resaddr6;
37	char tmpbuf[128];
38	char *pch;
39
40	REQUIRE(host != NULL);
41	REQUIRE(addr != NULL);
42
43	ZERO_SOCK(addr);
44
45	/*
46	 * Try IPv4, then IPv6.  In order to handle the extended format
47	 * for IPv6 scoped addresses (address%scope_ID), we'll use a local
48	 * working buffer of 128 bytes.  The length is an ad-hoc value, but
49	 * should be enough for this purpose; the buffer can contain a string
50	 * of at least 80 bytes for scope_ID in addition to any IPv6 numeric
51	 * addresses (up to 46 bytes), the delimiter character and the
52	 * terminating NULL character.
53	 */
54	if (AF_UNSPEC == af || AF_INET == af)
55		if (inet_pton(AF_INET, host, &in4) == 1) {
56			AF(addr) = AF_INET;
57			SET_ADDR4N(addr, in4.s_addr);
58
59			return TRUE;
60		}
61
62	if (AF_UNSPEC == af || AF_INET6 == af)
63		if (sizeof(tmpbuf) > strlen(host)) {
64			if ('[' == host[0]) {
65				strlcpy(tmpbuf, &host[1], sizeof(tmpbuf));
66				pch = strchr(tmpbuf, ']');
67				if (pch != NULL)
68					*pch = '\0';
69			} else {
70				strlcpy(tmpbuf, host, sizeof(tmpbuf));
71			}
72			ZERO(hints);
73			hints.ai_family = AF_INET6;
74			hints.ai_flags |= AI_NUMERICHOST;
75			if (getaddrinfo(tmpbuf, NULL, &hints, &result) == 0) {
76				AF(addr) = AF_INET6;
77				resaddr6 = UA_PTR(struct sockaddr_in6, result->ai_addr);
78				SET_ADDR6N(addr, resaddr6->sin6_addr);
79				SET_SCOPE(addr, resaddr6->sin6_scope_id);
80
81				freeaddrinfo(result);
82				return TRUE;
83			}
84		}
85	/*
86	 * If we got here it was not an IP address
87	 */
88	return FALSE;
89}
90