xref: /illumos-gate/usr/src/cmd/ypcmd/stdethers.c (revision 23c352973f956f97f817e65150aad7e1cebeb228)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 1987-1990,2002 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/types.h>
30 #include <sys/ethernet.h>
31 
32 #include <netdb.h>
33 #include <stdio.h>
34 #include <strings.h>
35 
36 /*
37  * Filter to convert addresses in /etc/ethers file to standard form
38  */
39 
40 int
41 main(int argc, char **argv)
42 {
43 	/*
44 	 * The hostname buffer must be at least as large as the line buffer
45 	 * to avoid buffer overflows when ether_line(3SOCKET) is called.
46 	 * We simply use the same size for both buffers to be safe.
47 	 */
48 	char line[MAXHOSTNAMELEN + 256], *lf, hostname[sizeof (line)];
49 	struct ether_addr e;
50 	FILE *in;
51 
52 	if (argc > 1) {
53 		in = fopen(argv[1], "r");
54 		if (in == NULL) {
55 			fprintf(stderr,
56 			    "%s: can't open %s\n", argv[0], argv[1]);
57 			return (1);
58 		}
59 	} else {
60 		in = stdin;
61 	}
62 	while (fgets(line, sizeof (line), in) != NULL) {
63 		lf = strchr(line, '\n');
64 		if (lf != NULL)
65 			*lf = '\0';
66 		if ((line[0] == '#') || (line[0] == '\0'))
67 			continue;
68 		if (ether_line(line, &e, hostname) == 0) {
69 			(void) fprintf(stdout, "%s\t%s\n", ether_ntoa(&e),
70 			    hostname);
71 		} else {
72 			(void) fprintf(stderr,
73 			    "%s: ignoring line: %s\n", argv[0], line);
74 		}
75 	}
76 	return (0);
77 }
78