xref: /freebsd/contrib/ntp/libntp/decodenetnum.c (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
1 /*
2  * decodenetnum - return a net number (this is crude, but careful)
3  */
4 #include <config.h>
5 #include <sys/types.h>
6 #include <ctype.h>
7 #ifdef HAVE_SYS_SOCKET_H
8 #include <sys/socket.h>
9 #endif
10 #ifdef HAVE_NETINET_IN_H
11 #include <netinet/in.h>
12 #endif
13 
14 #include "ntp.h"
15 #include "ntp_stdlib.h"
16 #include "ntp_assert.h"
17 
18 /*
19  * decodenetnum		convert text IP address and port to sockaddr_u
20  *
21  * Returns 0 for failure, 1 for success.
22  */
23 int
24 decodenetnum(
25 	const char *num,
26 	sockaddr_u *netnum
27 	)
28 {
29 	struct addrinfo hints, *ai = NULL;
30 	int err;
31 	u_short port;
32 	const char *cp;
33 	const char *port_str;
34 	char *pp;
35 	char *np;
36 	char name[80];
37 
38 	REQUIRE(num != NULL);
39 
40 	if (strlen(num) >= sizeof(name)) {
41 		return 0;
42 	}
43 
44 	port_str = NULL;
45 	if ('[' != num[0]) {
46 		/*
47 		 * to distinguish IPv6 embedded colons from a port
48 		 * specification on an IPv4 address, assume all
49 		 * legal IPv6 addresses have at least two colons.
50 		 */
51 		pp = strchr(num, ':');
52 		if (NULL == pp)
53 			cp = num;	/* no colons */
54 		else if (NULL != strchr(pp + 1, ':'))
55 			cp = num;	/* two or more colons */
56 		else {			/* one colon */
57 			strlcpy(name, num, sizeof(name));
58 			cp = name;
59 			pp = strchr(cp, ':');
60 			*pp = '\0';
61 			port_str = pp + 1;
62 		}
63 	} else {
64 		cp = num + 1;
65 		np = name;
66 		while (*cp && ']' != *cp)
67 			*np++ = *cp++;
68 		*np = 0;
69 		if (']' == cp[0] && ':' == cp[1] && '\0' != cp[2])
70 			port_str = &cp[2];
71 		cp = name;
72 	}
73 	ZERO(hints);
74 	hints.ai_flags = Z_AI_NUMERICHOST;
75 	err = getaddrinfo(cp, "ntp", &hints, &ai);
76 	if (err != 0)
77 		return 0;
78 	INSIST(ai->ai_addrlen <= sizeof(*netnum));
79 	ZERO(*netnum);
80 	memcpy(netnum, ai->ai_addr, ai->ai_addrlen);
81 	freeaddrinfo(ai);
82 	if (NULL == port_str || 1 != sscanf(port_str, "%hu", &port))
83 		port = NTP_PORT;
84 	SET_PORT(netnum, port);
85 	return 1;
86 }
87