1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
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 #if defined(LIBC_SCCS) && !defined(lint)
33 static char sccsid[] = "@(#)linkaddr.c 8.1 (Berkeley) 6/4/93";
34 #endif /* LIBC_SCCS and not lint */
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37
38 #include <sys/types.h>
39 #include <sys/socket.h>
40 #include <net/if.h>
41 #include <net/if_dl.h>
42 #include <string.h>
43
44 /* States*/
45 #define NAMING 0
46 #define GOTONE 1
47 #define GOTTWO 2
48 #define RESET 3
49 /* Inputs */
50 #define DIGIT (4*0)
51 #define END (4*1)
52 #define DELIM (4*2)
53 #define LETTER (4*3)
54
55 void
link_addr(const char * addr,struct sockaddr_dl * sdl)56 link_addr(const char *addr, struct sockaddr_dl *sdl)
57 {
58 char *cp = sdl->sdl_data;
59 char *cplim = sdl->sdl_len + (char *)sdl;
60 int byte = 0, state = NAMING, new;
61
62 bzero((char *)&sdl->sdl_family, sdl->sdl_len - 1);
63 sdl->sdl_family = AF_LINK;
64 do {
65 state &= ~LETTER;
66 if ((*addr >= '0') && (*addr <= '9')) {
67 new = *addr - '0';
68 } else if ((*addr >= 'a') && (*addr <= 'f')) {
69 new = *addr - 'a' + 10;
70 } else if ((*addr >= 'A') && (*addr <= 'F')) {
71 new = *addr - 'A' + 10;
72 } else if (*addr == 0) {
73 state |= END;
74 } else if (state == NAMING &&
75 (((*addr >= 'A') && (*addr <= 'Z')) ||
76 ((*addr >= 'a') && (*addr <= 'z'))))
77 state |= LETTER;
78 else
79 state |= DELIM;
80 addr++;
81 switch (state /* | INPUT */) {
82 case NAMING | DIGIT:
83 case NAMING | LETTER:
84 *cp++ = addr[-1];
85 continue;
86 case NAMING | DELIM:
87 state = RESET;
88 sdl->sdl_nlen = cp - sdl->sdl_data;
89 continue;
90 case GOTTWO | DIGIT:
91 *cp++ = byte;
92 /* FALLTHROUGH */
93 case RESET | DIGIT:
94 state = GOTONE;
95 byte = new;
96 continue;
97 case GOTONE | DIGIT:
98 state = GOTTWO;
99 byte = new + (byte << 4);
100 continue;
101 default: /* | DELIM */
102 state = RESET;
103 *cp++ = byte;
104 byte = 0;
105 continue;
106 case GOTONE | END:
107 case GOTTWO | END:
108 *cp++ = byte;
109 /* FALLTHROUGH */
110 case RESET | END:
111 break;
112 }
113 break;
114 } while (cp < cplim);
115 sdl->sdl_alen = cp - LLADDR(sdl);
116 new = cp - (char *)sdl;
117 if (new > sizeof(*sdl))
118 sdl->sdl_len = new;
119 return;
120 }
121
122 static const char hexlist[] = "0123456789abcdef";
123
124 char *
link_ntoa(const struct sockaddr_dl * sdl)125 link_ntoa(const struct sockaddr_dl *sdl)
126 {
127 static char obuf[64];
128 _Static_assert(sizeof(obuf) >= IFNAMSIZ + 20, "obuf is too small");
129 char *out;
130 const u_char *in, *inlim;
131 int namelen, i, rem;
132
133 namelen = (sdl->sdl_nlen <= IFNAMSIZ) ? sdl->sdl_nlen : IFNAMSIZ;
134
135 out = obuf;
136 rem = sizeof(obuf);
137 if (namelen > 0) {
138 bcopy(sdl->sdl_data, out, namelen);
139 out += namelen;
140 rem -= namelen;
141 if (sdl->sdl_alen > 0) {
142 *out++ = ':';
143 rem--;
144 }
145 }
146
147 in = (const u_char *)sdl->sdl_data + sdl->sdl_nlen;
148 inlim = in + sdl->sdl_alen;
149
150 while (in < inlim && rem > 1) {
151 if (in != (const u_char *)sdl->sdl_data + sdl->sdl_nlen) {
152 *out++ = '.';
153 rem--;
154 }
155 i = *in++;
156 if (i > 0xf) {
157 if (rem < 3)
158 break;
159 *out++ = hexlist[i >> 4];
160 *out++ = hexlist[i & 0xf];
161 rem -= 2;
162 } else {
163 if (rem < 2)
164 break;
165 *out++ = hexlist[i];
166 rem--;
167 }
168 }
169 *out = 0;
170 return (obuf);
171 }
172