xref: /freebsd/lib/libc/net/linkaddr.c (revision 3a31b7eb32ad60e1e05b2b2e184ff47e4afbb874)
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 
38 #include <sys/types.h>
39 #include <sys/socket.h>
40 #include <net/if_dl.h>
41 #include <string.h>
42 
43 /* States*/
44 #define NAMING	0
45 #define GOTONE	1
46 #define GOTTWO	2
47 #define RESET	3
48 /* Inputs */
49 #define	DIGIT	(4*0)
50 #define	END	(4*1)
51 #define DELIM	(4*2)
52 #define LETTER	(4*3)
53 
54 void
55 link_addr(addr, sdl)
56 	register const char *addr;
57 	register struct sockaddr_dl *sdl;
58 {
59 	register char *cp = sdl->sdl_data;
60 	char *cplim = sdl->sdl_len + (char *)sdl;
61 	register int byte = 0, state = NAMING, new;
62 
63 	bzero((char *)&sdl->sdl_family, sdl->sdl_len - 1);
64 	sdl->sdl_family = AF_LINK;
65 	do {
66 		state &= ~LETTER;
67 		if ((*addr >= '0') && (*addr <= '9')) {
68 			new = *addr - '0';
69 		} else if ((*addr >= 'a') && (*addr <= 'f')) {
70 			new = *addr - 'a' + 10;
71 		} else if ((*addr >= 'A') && (*addr <= 'F')) {
72 			new = *addr - 'A' + 10;
73 		} else if (*addr == 0) {
74 			state |= END;
75 		} else if (state == NAMING &&
76 			   (((*addr >= 'A') && (*addr <= 'Z')) ||
77 			   ((*addr >= 'a') && (*addr <= 'z'))))
78 			state |= LETTER;
79 		else
80 			state |= DELIM;
81 		addr++;
82 		switch (state /* | INPUT */) {
83 		case NAMING | DIGIT:
84 		case NAMING | LETTER:
85 			*cp++ = addr[-1];
86 			continue;
87 		case NAMING | DELIM:
88 			state = RESET;
89 			sdl->sdl_nlen = cp - sdl->sdl_data;
90 			continue;
91 		case GOTTWO | DIGIT:
92 			*cp++ = byte;
93 			/* FALLTHROUGH */
94 		case RESET | DIGIT:
95 			state = GOTONE;
96 			byte = new;
97 			continue;
98 		case GOTONE | DIGIT:
99 			state = GOTTWO;
100 			byte = new + (byte << 4);
101 			continue;
102 		default: /* | DELIM */
103 			state = RESET;
104 			*cp++ = byte;
105 			byte = 0;
106 			continue;
107 		case GOTONE | END:
108 		case GOTTWO | END:
109 			*cp++ = byte;
110 			/* FALLTHROUGH */
111 		case RESET | END:
112 			break;
113 		}
114 		break;
115 	} while (cp < cplim);
116 	sdl->sdl_alen = cp - LLADDR(sdl);
117 	new = cp - (char *)sdl;
118 	if (new > sizeof(*sdl))
119 		sdl->sdl_len = new;
120 	return;
121 }
122 
123 static char hexlist[] = "0123456789abcdef";
124 
125 char *
126 link_ntoa(sdl)
127 	register const struct sockaddr_dl *sdl;
128 {
129 	static char obuf[64];
130 	register char *out = obuf;
131 	register int i;
132 	register u_char *in = (u_char *)LLADDR(sdl);
133 	u_char *inlim = in + sdl->sdl_alen;
134 	int firsttime = 1;
135 
136 	if (sdl->sdl_nlen) {
137 		bcopy(sdl->sdl_data, obuf, sdl->sdl_nlen);
138 		out += sdl->sdl_nlen;
139 		if (sdl->sdl_alen)
140 			*out++ = ':';
141 	}
142 	while (in < inlim) {
143 		if (firsttime)
144 			firsttime = 0;
145 		else
146 			*out++ = '.';
147 		i = *in++;
148 		if (i > 0xf) {
149 			out[1] = hexlist[i & 0xf];
150 			i >>= 4;
151 			out[0] = hexlist[i];
152 			out += 2;
153 		} else
154 			*out++ = hexlist[i];
155 	}
156 	*out = 0;
157 	return (obuf);
158 }
159