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/types.h>
36 #include <sys/socket.h>
37 #include <net/if.h>
38 #include <net/if_dl.h>
39 #include <string.h>
40
41 /* States*/
42 #define NAMING 0
43 #define GOTONE 1
44 #define GOTTWO 2
45 #define RESET 3
46 /* Inputs */
47 #define DIGIT (4*0)
48 #define END (4*1)
49 #define DELIM (4*2)
50 #define LETTER (4*3)
51
52 void
link_addr(const char * addr,struct sockaddr_dl * sdl)53 link_addr(const char *addr, struct sockaddr_dl *sdl)
54 {
55 char *cp = sdl->sdl_data;
56 char *cplim = sdl->sdl_len + (char *)sdl;
57 int byte = 0, state = NAMING, new;
58
59 bzero((char *)&sdl->sdl_family, 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 static const char hexlist[] = "0123456789abcdef";
120
121 char *
link_ntoa(const struct sockaddr_dl * sdl)122 link_ntoa(const struct sockaddr_dl *sdl)
123 {
124 static char obuf[64];
125 _Static_assert(sizeof(obuf) >= IFNAMSIZ + 20, "obuf is too small");
126 char *out;
127 const u_char *in, *inlim;
128 int namelen, i, rem;
129
130 namelen = (sdl->sdl_nlen <= IFNAMSIZ) ? sdl->sdl_nlen : IFNAMSIZ;
131
132 out = obuf;
133 rem = sizeof(obuf);
134 if (namelen > 0) {
135 bcopy(sdl->sdl_data, out, namelen);
136 out += namelen;
137 rem -= namelen;
138 if (sdl->sdl_alen > 0) {
139 *out++ = ':';
140 rem--;
141 }
142 }
143
144 in = (const u_char *)sdl->sdl_data + sdl->sdl_nlen;
145 inlim = in + sdl->sdl_alen;
146
147 while (in < inlim && rem > 1) {
148 if (in != (const u_char *)sdl->sdl_data + sdl->sdl_nlen) {
149 *out++ = '.';
150 rem--;
151 }
152 i = *in++;
153 if (i > 0xf) {
154 if (rem < 3)
155 break;
156 *out++ = hexlist[i >> 4];
157 *out++ = hexlist[i & 0xf];
158 rem -= 2;
159 } else {
160 if (rem < 2)
161 break;
162 *out++ = hexlist[i];
163 rem--;
164 }
165 }
166 *out = 0;
167 return (obuf);
168 }
169