xref: /netbsd-src/sys/net/dl_print.c (revision 946379e7b37692fc43f68eb0d1c10daa0a7f3b6c)
1 /*	$NetBSD: dl_print.c,v 1.2 2014/12/02 19:34:33 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 2014 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 #include <sys/cdefs.h>
29 #include <sys/types.h>
30 
31 #ifdef _KERNEL
32 __KERNEL_RCSID(0, "$NetBSD: dl_print.c,v 1.2 2014/12/02 19:34:33 christos Exp $");
33 #include <sys/systm.h>
34 #else
35 __RCSID("$NetBSD: dl_print.c,v 1.2 2014/12/02 19:34:33 christos Exp $");
36 #include <stdio.h>
37 static const uint8_t hexdigits[] = "0123456789abcdef";
38 #endif
39 #include <net/if_dl.h>
40 
41 int
42 dl_print(char *buf, size_t len, const struct dl_addr *dl)
43 {
44 	const uint8_t *ap = (const uint8_t *)dl->dl_data;
45 	char abuf[256 * 3], *cp, *ecp;
46 
47 	ap += dl->dl_nlen;
48 	cp = abuf;
49 	ecp = abuf + sizeof(abuf);
50 
51 #define ADDC(c) do { \
52 		if (cp >= ecp) {\
53 			cp++; \
54 		} else \
55 			*cp++ = (char)(c); \
56 	} while (/*CONSTCOND*/0)
57 
58 #define ADDX(v) do { \
59 		uint8_t n = hexdigits[(v)]; \
60 		ADDC(n); \
61 	} while (/*CONSTCOND*/0)
62 
63 	for (size_t i = 0; i < dl->dl_alen; i++) {
64 		ADDX((u_int)ap[i] >> 4);
65 		ADDX(ap[i] & 0xf);
66 		ADDC(':');
67 	}
68 	if (cp > abuf)
69 		--cp;
70 	if (ecp > abuf) {
71 		if (cp < ecp)
72 			*cp = '\0';
73 		else
74 			*--ecp = '\0';
75 	}
76 	return snprintf(buf, len, "%.*s/%hhu#%s",
77 	    (int)dl->dl_nlen, dl->dl_data, dl->dl_type, abuf);
78 }
79 
80 int
81 sdl_print(char *buf, size_t len, const void *v)
82 {
83 	const struct sockaddr_dl *sdl = v;
84 	char abuf[LINK_ADDRSTRLEN];
85 
86 	dl_print(abuf, sizeof(abuf), &sdl->sdl_addr);
87 	return snprintf(buf, len, "[%s]:%hu", abuf, sdl->sdl_index);
88 }
89