xref: /freebsd/lib/libc/net/linkaddr.c (revision 6fd05b64b5b65dd4ba9b86482a0634a5f0b96c29)
1 /*-
2  * Copyright (c) 1990, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #if defined(LIBC_SCCS) && !defined(lint)
35 static char sccsid[] = "@(#)linkaddr.c	8.1 (Berkeley) 6/4/93";
36 #endif /* LIBC_SCCS and not lint */
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39 
40 #include <sys/types.h>
41 #include <sys/socket.h>
42 #include <net/if_dl.h>
43 #include <string.h>
44 
45 /* States*/
46 #define NAMING	0
47 #define GOTONE	1
48 #define GOTTWO	2
49 #define RESET	3
50 /* Inputs */
51 #define	DIGIT	(4*0)
52 #define	END	(4*1)
53 #define DELIM	(4*2)
54 #define LETTER	(4*3)
55 
56 void
57 link_addr(addr, sdl)
58 	const char *addr;
59 	struct sockaddr_dl *sdl;
60 {
61 	char *cp = sdl->sdl_data;
62 	char *cplim = sdl->sdl_len + (char *)sdl;
63 	int byte = 0, state = NAMING, new;
64 
65 	bzero((char *)&sdl->sdl_family, sdl->sdl_len - 1);
66 	sdl->sdl_family = AF_LINK;
67 	do {
68 		state &= ~LETTER;
69 		if ((*addr >= '0') && (*addr <= '9')) {
70 			new = *addr - '0';
71 		} else if ((*addr >= 'a') && (*addr <= 'f')) {
72 			new = *addr - 'a' + 10;
73 		} else if ((*addr >= 'A') && (*addr <= 'F')) {
74 			new = *addr - 'A' + 10;
75 		} else if (*addr == 0) {
76 			state |= END;
77 		} else if (state == NAMING &&
78 			   (((*addr >= 'A') && (*addr <= 'Z')) ||
79 			   ((*addr >= 'a') && (*addr <= 'z'))))
80 			state |= LETTER;
81 		else
82 			state |= DELIM;
83 		addr++;
84 		switch (state /* | INPUT */) {
85 		case NAMING | DIGIT:
86 		case NAMING | LETTER:
87 			*cp++ = addr[-1];
88 			continue;
89 		case NAMING | DELIM:
90 			state = RESET;
91 			sdl->sdl_nlen = cp - sdl->sdl_data;
92 			continue;
93 		case GOTTWO | DIGIT:
94 			*cp++ = byte;
95 			/* FALLTHROUGH */
96 		case RESET | DIGIT:
97 			state = GOTONE;
98 			byte = new;
99 			continue;
100 		case GOTONE | DIGIT:
101 			state = GOTTWO;
102 			byte = new + (byte << 4);
103 			continue;
104 		default: /* | DELIM */
105 			state = RESET;
106 			*cp++ = byte;
107 			byte = 0;
108 			continue;
109 		case GOTONE | END:
110 		case GOTTWO | END:
111 			*cp++ = byte;
112 			/* FALLTHROUGH */
113 		case RESET | END:
114 			break;
115 		}
116 		break;
117 	} while (cp < cplim);
118 	sdl->sdl_alen = cp - LLADDR(sdl);
119 	new = cp - (char *)sdl;
120 	if (new > sizeof(*sdl))
121 		sdl->sdl_len = new;
122 	return;
123 }
124 
125 static char hexlist[] = "0123456789abcdef";
126 
127 char *
128 link_ntoa(sdl)
129 	const struct sockaddr_dl *sdl;
130 {
131 	static char obuf[64];
132 	char *out = obuf;
133 	int i;
134 	u_char *in = (u_char *)LLADDR(sdl);
135 	u_char *inlim = in + sdl->sdl_alen;
136 	int firsttime = 1;
137 
138 	if (sdl->sdl_nlen) {
139 		bcopy(sdl->sdl_data, obuf, sdl->sdl_nlen);
140 		out += sdl->sdl_nlen;
141 		if (sdl->sdl_alen)
142 			*out++ = ':';
143 	}
144 	while (in < inlim) {
145 		if (firsttime)
146 			firsttime = 0;
147 		else
148 			*out++ = '.';
149 		i = *in++;
150 		if (i > 0xf) {
151 			out[1] = hexlist[i & 0xf];
152 			i >>= 4;
153 			out[0] = hexlist[i];
154 			out += 2;
155 		} else
156 			*out++ = hexlist[i];
157 	}
158 	*out = 0;
159 	return (obuf);
160 }
161