lib/isc/netscope.c

	netscope.c revision dafcb997e390efa4423883dafd100c975c4095d6
/*
 * Copyright (C) 2004  Internet Systems Consortium, Inc. ("ISC")
 * Copyright (C) 2002  Internet Software Consortium.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char rcsid[] =
    "$Id: netscope.c,v 1.6 2004/03/05 05:10:47 marka Exp $";
#endif /* LIBC_SCCS and not lint */

#include <isc/string.h>
#include <isc/net.h>
#include <isc/netscope.h>
#include <isc/result.h>

isc_result_t
isc_netscope_pton(int af, char *scopename, void *addr, isc_uint32_t *zoneid) {
    char *ep;
    unsigned int ifid;
    struct in6_addr *in6;
    isc_uint32_t zone;
    isc_uint64_t llz;

    /* at this moment, we only support AF_INET6 */
    if (af != AF_INET6)
        return (ISC_R_FAILURE);

    in6 = (struct in6_addr *)addr;

    /*
     * Basically, "names" are more stable than numeric IDs in terms of
     * renumbering, and are more preferred.  However, since there is no
     * standard naming convention and APIs to deal with the names.  Thus,
     * we only handle the case of link-local addresses, for which we use
     * interface names as link names, assuming one to one mapping between
     * interfaces and links.
     */
#ifdef ISC_PLATFORM_HAVEIFNAMETOINDEX
    if (IN6_IS_ADDR_LINKLOCAL(in6) &&
        (ifid = if_nametoindex((const char *)scopename)) != 0)
        zone = (isc_uint32_t)ifid;
    else {
#endif
        llz = isc_string_touint64(scopename, &ep, 10);
        if (ep == scopename)
            return (ISC_R_FAILURE);

        /* check overflow */
        zone = (isc_uint32_t)(llz & 0xffffffffUL);
        if (zone != llz)
            return (ISC_R_FAILURE);
#ifdef ISC_PLATFORM_HAVEIFNAMETOINDEX
    }
#endif

    *zoneid = zone;
    return (ISC_R_SUCCESS);
}