xref: /freebsd/contrib/ntp/libntp/lib/isc/netscope.c (revision ba3c1f5972d7b90feb6e6da47905ff2757e0fe57)
1 /*
2  * Copyright (C) 2004-2007  Internet Systems Consortium, Inc. ("ISC")
3  * Copyright (C) 2002  Internet Software Consortium.
4  *
5  * Permission to use, copy, modify, and/or distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
15  * PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 /*! \file */
19 
20 #if defined(LIBC_SCCS) && !defined(lint)
21 static char rcsid[] =
22 	"$Id: netscope.c,v 1.13 2007/06/19 23:47:17 tbox Exp $";
23 #endif /* LIBC_SCCS and not lint */
24 
25 #include <config.h>
26 
27 #include <isc/string.h>
28 #include <isc/net.h>
29 #include <isc/netscope.h>
30 #include <isc/result.h>
31 
32 isc_result_t
33 isc_netscope_pton(int af, char *scopename, void *addr, isc_uint32_t *zoneid) {
34 	char *ep;
35 #ifdef ISC_PLATFORM_HAVEIFNAMETOINDEX
36 	unsigned int ifid;
37 #endif
38 	struct in6_addr *in6;
39 	isc_uint32_t zone;
40 	isc_uint64_t llz;
41 
42 	/* at this moment, we only support AF_INET6 */
43 	if (af != AF_INET6)
44 		return (ISC_R_FAILURE);
45 
46 	in6 = (struct in6_addr *)addr;
47 
48 	/*
49 	 * Basically, "names" are more stable than numeric IDs in terms of
50 	 * renumbering, and are more preferred.  However, since there is no
51 	 * standard naming convention and APIs to deal with the names.  Thus,
52 	 * we only handle the case of link-local addresses, for which we use
53 	 * interface names as link names, assuming one to one mapping between
54 	 * interfaces and links.
55 	 */
56 #ifdef ISC_PLATFORM_HAVEIFNAMETOINDEX
57 	if (IN6_IS_ADDR_LINKLOCAL(in6) &&
58 	    (ifid = if_nametoindex((const char *)scopename)) != 0)
59 		zone = (isc_uint32_t)ifid;
60 	else {
61 #endif
62 		llz = isc_string_touint64(scopename, &ep, 10);
63 		if (ep == scopename)
64 			return (ISC_R_FAILURE);
65 
66 		/* check overflow */
67 		zone = (isc_uint32_t)(llz & 0xffffffffUL);
68 		if (zone != llz)
69 			return (ISC_R_FAILURE);
70 #ifdef ISC_PLATFORM_HAVEIFNAMETOINDEX
71 	}
72 #endif
73 
74 	*zoneid = zone;
75 	return (ISC_R_SUCCESS);
76 }
77