248 lines
6.2 KiB
C
248 lines
6.2 KiB
C
/* inet.c
|
|
|
|
Subroutines to manipulate internet addresses in a safely portable
|
|
way... */
|
|
|
|
/*
|
|
* Copyright (c) 2004-2005 by Internet Systems Consortium, Inc. ("ISC")
|
|
* Copyright (c) 1995-2003 by 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.
|
|
*
|
|
* Internet Systems Consortium, Inc.
|
|
* 950 Charter Street
|
|
* Redwood City, CA 94063
|
|
* <info@isc.org>
|
|
* http://www.isc.org/
|
|
*
|
|
* This software has been written for Internet Systems Consortium
|
|
* by Ted Lemon in cooperation with Vixie Enterprises and Nominum, Inc.
|
|
* To learn more about Internet Systems Consortium, see
|
|
* ``http://www.isc.org/''. To learn more about Vixie Enterprises,
|
|
* see ``http://www.vix.com''. To learn more about Nominum, Inc., see
|
|
* ``http://www.nominum.com''.
|
|
*/
|
|
|
|
#ifndef lint
|
|
static char copyright[] =
|
|
"$Id: inet.c,v 1.4 2005/08/11 17:13:21 drochner Exp $ Copyright (c) 2004-2005 Internet Systems Consortium. All rights reserved.\n";
|
|
#endif /* not lint */
|
|
|
|
#include "dhcpd.h"
|
|
|
|
/* Return just the network number of an internet address... */
|
|
|
|
struct iaddr subnet_number (addr, mask)
|
|
struct iaddr addr;
|
|
struct iaddr mask;
|
|
{
|
|
int i;
|
|
struct iaddr rv;
|
|
|
|
if (addr.len > sizeof(addr.iabuf))
|
|
log_fatal("subnet_number():%s:%d: Invalid addr length.", MDL);
|
|
if (addr.len != mask.len)
|
|
log_fatal("subnet_number():%s:%d: Addr/mask length mismatch.",
|
|
MDL);
|
|
|
|
rv.len = 0;
|
|
|
|
/* Both addresses must have the same length... */
|
|
if (addr.len != mask.len)
|
|
return rv;
|
|
|
|
rv.len = addr.len;
|
|
for (i = 0; i < rv.len; i++)
|
|
rv.iabuf [i] = addr.iabuf [i] & mask.iabuf [i];
|
|
return rv;
|
|
}
|
|
|
|
/* Combine a network number and a integer to produce an internet address.
|
|
This won't work for subnets with more than 32 bits of host address, but
|
|
maybe this isn't a problem. */
|
|
|
|
struct iaddr ip_addr (subnet, mask, host_address)
|
|
struct iaddr subnet;
|
|
struct iaddr mask;
|
|
u_int32_t host_address;
|
|
{
|
|
int i, j, k;
|
|
u_int32_t swaddr;
|
|
struct iaddr rv;
|
|
unsigned char habuf [sizeof swaddr];
|
|
|
|
if (subnet.len > sizeof(subnet.iabuf))
|
|
log_fatal("ip_addr():%s:%d: Invalid addr length.", MDL);
|
|
if (subnet.len != mask.len)
|
|
log_fatal("ip_addr():%s:%d: Addr/mask length mismatch.",
|
|
MDL);
|
|
|
|
swaddr = htonl (host_address);
|
|
memcpy (habuf, &swaddr, sizeof swaddr);
|
|
|
|
/* Combine the subnet address and the host address. If
|
|
the host address is bigger than can fit in the subnet,
|
|
return a zero-length iaddr structure. */
|
|
rv = subnet;
|
|
j = rv.len - sizeof habuf;
|
|
for (i = sizeof habuf - 1; i >= 0; i--) {
|
|
if (mask.iabuf [i + j]) {
|
|
if (habuf [i] > (mask.iabuf [i + j] ^ 0xFF)) {
|
|
rv.len = 0;
|
|
return rv;
|
|
}
|
|
for (k = i - 1; k >= 0; k--) {
|
|
if (habuf [k]) {
|
|
rv.len = 0;
|
|
return rv;
|
|
}
|
|
}
|
|
rv.iabuf [i + j] |= habuf [i];
|
|
break;
|
|
} else
|
|
rv.iabuf [i + j] = habuf [i];
|
|
}
|
|
|
|
return rv;
|
|
}
|
|
|
|
/* Given a subnet number and netmask, return the address on that subnet
|
|
for which the host portion of the address is all ones (the standard
|
|
broadcast address). */
|
|
|
|
struct iaddr broadcast_addr (subnet, mask)
|
|
struct iaddr subnet;
|
|
struct iaddr mask;
|
|
{
|
|
int i;
|
|
struct iaddr rv;
|
|
|
|
if (subnet.len > sizeof(subnet.iabuf))
|
|
log_fatal("broadcast_addr():%s:%d: Invalid addr length.", MDL);
|
|
if (subnet.len != mask.len)
|
|
log_fatal("broadcast_addr():%s:%d: Addr/mask length mismatch.",
|
|
MDL);
|
|
|
|
if (subnet.len != mask.len) {
|
|
rv.len = 0;
|
|
return rv;
|
|
}
|
|
|
|
for (i = 0; i < subnet.len; i++) {
|
|
rv.iabuf [i] = subnet.iabuf [i] | (~mask.iabuf [i] & 255);
|
|
}
|
|
rv.len = subnet.len;
|
|
|
|
return rv;
|
|
}
|
|
|
|
u_int32_t host_addr (addr, mask)
|
|
struct iaddr addr;
|
|
struct iaddr mask;
|
|
{
|
|
int i;
|
|
u_int32_t swaddr;
|
|
struct iaddr rv;
|
|
|
|
if (addr.len > sizeof(addr.iabuf))
|
|
log_fatal("host_addr():%s:%d: Invalid addr length.", MDL);
|
|
if (addr.len != mask.len)
|
|
log_fatal("host_addr():%s:%d: Addr/mask length mismatch.",
|
|
MDL);
|
|
|
|
rv.len = 0;
|
|
|
|
/* Mask out the network bits... */
|
|
rv.len = addr.len;
|
|
for (i = 0; i < rv.len; i++)
|
|
rv.iabuf [i] = addr.iabuf [i] & ~mask.iabuf [i];
|
|
|
|
/* Copy out up to 32 bits... */
|
|
memcpy (&swaddr, &rv.iabuf [rv.len - sizeof swaddr], sizeof swaddr);
|
|
|
|
/* Swap it and return it. */
|
|
return ntohl (swaddr);
|
|
}
|
|
|
|
int addr_eq (addr1, addr2)
|
|
struct iaddr addr1, addr2;
|
|
{
|
|
if (addr1.len > sizeof(addr1.iabuf))
|
|
log_fatal("addr_eq():%s:%d: Invalid addr length.", MDL);
|
|
|
|
if (addr1.len != addr2.len)
|
|
return 0;
|
|
return memcmp (addr1.iabuf, addr2.iabuf, addr1.len) == 0;
|
|
}
|
|
|
|
char *piaddr (addr)
|
|
struct iaddr addr;
|
|
{
|
|
static char pbuf [4 * 16];
|
|
char *s = pbuf;
|
|
int i;
|
|
|
|
if (addr.len > sizeof(addr.iabuf))
|
|
log_fatal("piaddr():%s:%d: Address length too long.", MDL);
|
|
|
|
if (addr.len == 0) {
|
|
strcpy (s, "<null address>");
|
|
}
|
|
for (i = 0; i < addr.len; i++) {
|
|
sprintf (s, "%s%d", i ? "." : "", addr.iabuf [i]);
|
|
s += strlen (s);
|
|
}
|
|
return pbuf;
|
|
}
|
|
|
|
char *piaddrmask (struct iaddr addr, struct iaddr mask,
|
|
const char *file, int line)
|
|
{
|
|
char *s, tbuf[sizeof("255.255.255.255/32")];
|
|
int mw;
|
|
unsigned i, oct, bit;
|
|
|
|
if (addr.len != 4)
|
|
log_fatal("piaddrmask():%s:%d: Address length %d invalid",
|
|
MDL, addr.len);
|
|
if (addr.len != mask.len)
|
|
log_fatal("piaddrmask():%s:%d: Address and mask size mismatch",
|
|
MDL);
|
|
|
|
/* Determine netmask width in bits. */
|
|
for (mw = 32; mw > 0; ) {
|
|
oct = (mw - 1) / 8;
|
|
bit = 0x80 >> ((mw - 1) % 8);
|
|
if (!mask.iabuf [oct])
|
|
mw -= 8;
|
|
else if (mask.iabuf [oct] & bit)
|
|
break;
|
|
else
|
|
mw--;
|
|
}
|
|
|
|
s = tbuf;
|
|
for (i = 0 ; i <= oct ; i++) {
|
|
sprintf(s, "%s%d", i ? "." : "", addr.iabuf[i]);
|
|
s += strlen(s);
|
|
}
|
|
sprintf(s, "/%d", mw);
|
|
|
|
s = dmalloc (strlen(tbuf) + 1, file, line);
|
|
if (!s)
|
|
return s;
|
|
strcpy(s, tbuf);
|
|
return s;
|
|
}
|
|
|