1 /*	$OpenBSD: linkaddr.c,v 1.5 2005/08/06 20:30:03 espie Exp $ */
2 /*-
3  * Copyright (c) 1990, 1993
4  *	The Regents of the University of California.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. Neither the name of the University nor the names of its contributors
15  *    may be used to endorse or promote products derived from this software
16  *    without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/types.h>
32 #include <sys/socket.h>
33 #include <net/if_dl.h>
34 #include <string.h>
35 
36 __RCSID("$MirOS: src/lib/libc/net/linkaddr.c,v 1.6 2010/01/07 22:34:53 tg Exp $");
37 
38 extern const uint8_t mbsd_digits_hex[17];
39 
40 /* States*/
41 #define NAMING	0
42 #define GOTONE	1
43 #define GOTTWO	2
44 #define RESET	3
45 /* Inputs */
46 #define	DIGIT	(4*0)
47 #define	END	(4*1)
48 #define DELIM	(4*2)
49 #define LETTER	(4*3)
50 
51 void
link_addr(const char * addr,struct sockaddr_dl * sdl)52 link_addr(const char *addr, struct sockaddr_dl *sdl)
53 {
54 	char *cp = sdl->sdl_data;
55 	char *cplim = sdl->sdl_len + (char *)sdl;
56 	int byte = 0, state = NAMING;
57 	size_t new = 0;
58 
59 	memset((char *)&sdl->sdl_family, 0, sdl->sdl_len - 1);
60 	sdl->sdl_family = AF_LINK;
61 	do {
62 		state &= ~LETTER;
63 		if ((*addr >= '0') && (*addr <= '9')) {
64 			new = *addr - '0';
65 		} else if ((*addr >= 'a') && (*addr <= 'f')) {
66 			new = *addr - 'a' + 10;
67 		} else if ((*addr >= 'A') && (*addr <= 'F')) {
68 			new = *addr - 'A' + 10;
69 		} else if (*addr == 0) {
70 			state |= END;
71 		} else if (state == NAMING &&
72 			   (((*addr >= 'A') && (*addr <= 'Z')) ||
73 			   ((*addr >= 'a') && (*addr <= 'z'))))
74 			state |= LETTER;
75 		else
76 			state |= DELIM;
77 		addr++;
78 		switch (state /* | INPUT */) {
79 		case NAMING | DIGIT:
80 		case NAMING | LETTER:
81 			*cp++ = addr[-1];
82 			continue;
83 		case NAMING | DELIM:
84 			state = RESET;
85 			sdl->sdl_nlen = cp - sdl->sdl_data;
86 			continue;
87 		case GOTTWO | DIGIT:
88 			*cp++ = byte;
89 			/* FALLTHROUGH */
90 		case RESET | DIGIT:
91 			state = GOTONE;
92 			byte = new;
93 			continue;
94 		case GOTONE | DIGIT:
95 			state = GOTTWO;
96 			byte = new + (byte << 4);
97 			continue;
98 		default: /* | DELIM */
99 			state = RESET;
100 			*cp++ = byte;
101 			byte = 0;
102 			continue;
103 		case GOTONE | END:
104 		case GOTTWO | END:
105 			*cp++ = byte;
106 			/* FALLTHROUGH */
107 		case RESET | END:
108 			break;
109 		}
110 		break;
111 	} while (cp < cplim);
112 	sdl->sdl_alen = cp - LLADDR(sdl);
113 	new = cp - (char *)sdl;
114 	if (new > sizeof(*sdl))
115 		sdl->sdl_len = new;
116 	return;
117 }
118 
119 char *
link_ntoa(const struct sockaddr_dl * sdl)120 link_ntoa(const struct sockaddr_dl *sdl)
121 {
122 	static char obuf[64];
123 	char *out = obuf;
124 	int i;
125 	u_char *in = (u_char *)LLADDR(sdl);
126 	u_char *inlim = in + sdl->sdl_alen;
127 	int firsttime = 1;
128 
129 	if (sdl->sdl_nlen) {
130 		memmove(obuf, sdl->sdl_data, sdl->sdl_nlen);
131 		out += sdl->sdl_nlen;
132 		if (sdl->sdl_alen)
133 			*out++ = ':';
134 	}
135 	while (in < inlim) {
136 		if (firsttime)
137 			firsttime = 0;
138 		else
139 			*out++ = '.';
140 		i = *in++;
141 		if (i > 0xf) {
142 			out[1] = mbsd_digits_hex[i & 0xf];
143 			i >>= 4;
144 			out[0] = mbsd_digits_hex[i];
145 			out += 2;
146 		} else
147 			*out++ = mbsd_digits_hex[i];
148 	}
149 	*out = 0;
150 	return (obuf);
151 }
152