xref: /minix/lib/libc/net/linkaddr.c (revision f14fb602)
1 /*	$NetBSD: linkaddr.c,v 1.16 2012/03/20 17:44:18 matt Exp $	*/
2 
3 /*-
4  * Copyright (c) 1990, 1993
5  *	The Regents of the University of California.  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  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #if defined(LIBC_SCCS) && !defined(lint)
34 #if 0
35 static char sccsid[] = "@(#)linkaddr.c	8.1 (Berkeley) 6/4/93";
36 #else
37 __RCSID("$NetBSD: linkaddr.c,v 1.16 2012/03/20 17:44:18 matt Exp $");
38 #endif
39 #endif /* LIBC_SCCS and not lint */
40 
41 #include <sys/types.h>
42 #include <sys/socket.h>
43 #include <net/if_dl.h>
44 
45 #include <assert.h>
46 #include <string.h>
47 
48 /* States*/
49 #define NAMING	0
50 #define GOTONE	1
51 #define GOTTWO	2
52 #define RESET	3
53 /* Inputs */
54 #define	DIGIT	(4*0)
55 #define	END	(4*1)
56 #define DELIM	(4*2)
57 #define LETTER	(4*3)
58 
59 void
link_addr(const char * addr,struct sockaddr_dl * sdl)60 link_addr(const char *addr, struct sockaddr_dl *sdl)
61 {
62 	register char *cp = sdl->sdl_data;
63 	char *cplim = sdl->sdl_len + (char *)(void *)sdl;
64 	int byte = 0, state = NAMING;
65 	size_t newaddr = 0;	/* pacify gcc */
66 
67 	_DIAGASSERT(addr != NULL);
68 	_DIAGASSERT(sdl != NULL);
69 
70 	(void)memset(&sdl->sdl_family, 0, (size_t)sdl->sdl_len - 1);
71 	sdl->sdl_family = AF_LINK;
72 	do {
73 		state &= ~LETTER;
74 		if ((*addr >= '0') && (*addr <= '9')) {
75 			newaddr = *addr - '0';
76 		} else if ((*addr >= 'a') && (*addr <= 'f')) {
77 			newaddr = *addr - 'a' + 10;
78 		} else if ((*addr >= 'A') && (*addr <= 'F')) {
79 			newaddr = *addr - 'A' + 10;
80 		} else if (*addr == 0) {
81 			state |= END;
82 		} else if (state == NAMING &&
83 			   (((*addr >= 'A') && (*addr <= 'Z')) ||
84 			   ((*addr >= 'a') && (*addr <= 'z'))))
85 			state |= LETTER;
86 		else
87 			state |= DELIM;
88 		addr++;
89 		switch (state /* | INPUT */) {
90 		case NAMING | DIGIT:
91 		case NAMING | LETTER:
92 			*cp++ = addr[-1];
93 			continue;
94 		case NAMING | DELIM:
95 			state = RESET;
96 			_DIAGASSERT(__type_fit(uint8_t, cp - sdl->sdl_data));
97 			sdl->sdl_nlen = (uint8_t)(cp - sdl->sdl_data);
98 			continue;
99 		case GOTTWO | DIGIT:
100 			*cp++ = byte;
101 			/* FALLTHROUGH */
102 		case RESET | DIGIT:
103 			state = GOTONE;
104 			byte = (int)newaddr;
105 			continue;
106 		case GOTONE | DIGIT:
107 			state = GOTTWO;
108 			byte = (int)newaddr + (byte << 4);
109 			continue;
110 		default: /* | DELIM */
111 			state = RESET;
112 			*cp++ = byte;
113 			byte = 0;
114 			continue;
115 		case GOTONE | END:
116 		case GOTTWO | END:
117 			*cp++ = byte;
118 			/* FALLTHROUGH */
119 		case RESET | END:
120 			break;
121 		}
122 		break;
123 	} while (cp < cplim);
124 
125 	_DIAGASSERT(__type_fit(uint8_t, cp - LLADDR(sdl)));
126 	sdl->sdl_alen = (uint8_t)(cp - LLADDR(sdl));
127 	newaddr = cp - (char *)(void *)sdl;
128 	if (newaddr > sizeof(*sdl)) {
129 		_DIAGASSERT(__type_fit(uint8_t, newaddr));
130 		sdl->sdl_len = (uint8_t)newaddr;
131 	}
132 	return;
133 }
134 
135 static const char hexlist[16] = "0123456789abcdef";
136 
137 char *
link_ntoa(const struct sockaddr_dl * sdl)138 link_ntoa(const struct sockaddr_dl *sdl)
139 {
140 	static char obuf[64];
141 	register char *out = obuf;
142 	register size_t i;
143 	const u_char *in = (const u_char *)CLLADDR(sdl);
144 	const u_char *inlim = in + sdl->sdl_alen;
145 	int firsttime = 1;
146 
147 	_DIAGASSERT(sdl != NULL);
148 
149 	if (sdl->sdl_nlen) {
150 		(void)memcpy(obuf, sdl->sdl_data, (size_t)sdl->sdl_nlen);
151 		out += sdl->sdl_nlen;
152 		if (sdl->sdl_alen)
153 			*out++ = ':';
154 	}
155 	while (in < inlim) {
156 		if (firsttime)
157 			firsttime = 0;
158 		else
159 			*out++ = '.';
160 		i = *in++;
161 		if (i > 0xf) {
162 			out[1] = hexlist[i & 0xf];
163 			i >>= 4;
164 			out[0] = hexlist[i];
165 			out += 2;
166 		} else
167 			*out++ = hexlist[i];
168 	}
169 	*out = 0;
170 	return (obuf);
171 }
172