1 |
|
|
/* $OpenBSD: inet_netof.c,v 1.7 2015/01/16 16:48:51 deraadt Exp $ */ |
2 |
|
|
/* |
3 |
|
|
* Copyright (c) 1983, 1993 |
4 |
|
|
* The Regents of the University of California. All rights reserved. |
5 |
|
|
* |
6 |
|
|
* Redistribution and use in source and binary forms, with or without |
7 |
|
|
* modification, are permitted provided that the following conditions |
8 |
|
|
* are met: |
9 |
|
|
* 1. Redistributions of source code must retain the above copyright |
10 |
|
|
* notice, this list of conditions and the following disclaimer. |
11 |
|
|
* 2. Redistributions in binary form must reproduce the above copyright |
12 |
|
|
* notice, this list of conditions and the following disclaimer in the |
13 |
|
|
* documentation and/or other materials provided with the distribution. |
14 |
|
|
* 3. Neither the name of the University nor the names of its contributors |
15 |
|
|
* may be used to endorse or promote products derived from this software |
16 |
|
|
* without specific prior written permission. |
17 |
|
|
* |
18 |
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
19 |
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
20 |
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
21 |
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
22 |
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
23 |
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
24 |
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
25 |
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
26 |
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
27 |
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
28 |
|
|
* SUCH DAMAGE. |
29 |
|
|
*/ |
30 |
|
|
|
31 |
|
|
#include <netinet/in.h> |
32 |
|
|
#include <arpa/inet.h> |
33 |
|
|
|
34 |
|
|
/* |
35 |
|
|
* Return the network number from an internet |
36 |
|
|
* address; handles class a/b/c network #'s. |
37 |
|
|
*/ |
38 |
|
|
in_addr_t |
39 |
|
|
inet_netof(struct in_addr in) |
40 |
|
|
{ |
41 |
|
|
in_addr_t i = ntohl(in.s_addr); |
42 |
|
|
|
43 |
|
|
if (IN_CLASSA(i)) |
44 |
|
|
return (((i)&IN_CLASSA_NET) >> IN_CLASSA_NSHIFT); |
45 |
|
|
else if (IN_CLASSB(i)) |
46 |
|
|
return (((i)&IN_CLASSB_NET) >> IN_CLASSB_NSHIFT); |
47 |
|
|
else |
48 |
|
|
return (((i)&IN_CLASSC_NET) >> IN_CLASSC_NSHIFT); |
49 |
|
|
} |