xref: /netbsd-src/external/bsd/ntp/dist/libntp/decodenetnum.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: decodenetnum.c,v 1.5 2016/01/08 21:35:38 christos Exp $	*/
2 
3 /*
4  * decodenetnum - return a net number (this is crude, but careful)
5  */
6 #include <config.h>
7 #include <sys/types.h>
8 #include <ctype.h>
9 #ifdef HAVE_SYS_SOCKET_H
10 #include <sys/socket.h>
11 #endif
12 #ifdef HAVE_NETINET_IN_H
13 #include <netinet/in.h>
14 #endif
15 
16 #include "ntp.h"
17 #include "ntp_stdlib.h"
18 #include "ntp_assert.h"
19 
20 /*
21  * decodenetnum		convert text IP address and port to sockaddr_u
22  *
23  * Returns 0 for failure, 1 for success.
24  */
25 int
26 decodenetnum(
27 	const char *num,
28 	sockaddr_u *netnum
29 	)
30 {
31 	struct addrinfo hints, *ai = NULL;
32 	int err;
33 	u_short port;
34 	const char *cp;
35 	const char *port_str;
36 	char *pp;
37 	char *np;
38 	char name[80];
39 
40 	REQUIRE(num != NULL);
41 
42 	if (strlen(num) >= sizeof(name)) {
43 		return 0;
44 	}
45 
46 	port_str = NULL;
47 	if ('[' != num[0]) {
48 		/*
49 		 * to distinguish IPv6 embedded colons from a port
50 		 * specification on an IPv4 address, assume all
51 		 * legal IPv6 addresses have at least two colons.
52 		 */
53 		pp = strchr(num, ':');
54 		if (NULL == pp)
55 			cp = num;	/* no colons */
56 		else if (NULL != strchr(pp + 1, ':'))
57 			cp = num;	/* two or more colons */
58 		else {			/* one colon */
59 			strlcpy(name, num, sizeof(name));
60 			cp = name;
61 			pp = strchr(cp, ':');
62 			*pp = '\0';
63 			port_str = pp + 1;
64 		}
65 	} else {
66 		cp = num + 1;
67 		np = name;
68 		while (*cp && ']' != *cp)
69 			*np++ = *cp++;
70 		*np = 0;
71 		if (']' == cp[0] && ':' == cp[1] && '\0' != cp[2])
72 			port_str = &cp[2];
73 		cp = name;
74 	}
75 	ZERO(hints);
76 	hints.ai_flags = Z_AI_NUMERICHOST;
77 	err = getaddrinfo(cp, "ntp", &hints, &ai);
78 	if (err != 0)
79 		return 0;
80 	INSIST(ai->ai_addrlen <= sizeof(*netnum));
81 	ZERO(*netnum);
82 	memcpy(netnum, ai->ai_addr, ai->ai_addrlen);
83 	freeaddrinfo(ai);
84 	if (NULL == port_str || 1 != sscanf(port_str, "%hu", &port))
85 		port = NTP_PORT;
86 	SET_PORT(netnum, port);
87 	return 1;
88 }
89