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. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * @(#)linkaddr.c 8.1 (Berkeley) 6/4/93
30 * $FreeBSD: head/lib/libc/net/linkaddr.c 309688 2016-12-07 23:18:00Z glebius $
31 */
32
33 #include <sys/types.h>
34 #include <sys/socket.h>
35 #include <net/if.h>
36 #include <net/if_dl.h>
37 #include <string.h>
38
39 /* States*/
40 #define NAMING 0
41 #define GOTONE 1
42 #define GOTTWO 2
43 #define RESET 3
44 /* Inputs */
45 #define DIGIT (4*0)
46 #define END (4*1)
47 #define DELIM (4*2)
48 #define LETTER (4*3)
49
50 void
link_addr(const char * addr,struct sockaddr_dl * sdl)51 link_addr(const char *addr, struct sockaddr_dl *sdl)
52 {
53 char *cp = sdl->sdl_data;
54 char *cplim = sdl->sdl_len + (char *)sdl;
55 int byte = 0, state = NAMING, new;
56
57 bzero((char *)&sdl->sdl_family, sdl->sdl_len - 1);
58 sdl->sdl_family = AF_LINK;
59 do {
60 state &= ~LETTER;
61 if ((*addr >= '0') && (*addr <= '9')) {
62 new = *addr - '0';
63 } else if ((*addr >= 'a') && (*addr <= 'f')) {
64 new = *addr - 'a' + 10;
65 } else if ((*addr >= 'A') && (*addr <= 'F')) {
66 new = *addr - 'A' + 10;
67 } else if (*addr == 0) {
68 state |= END;
69 } else if (state == NAMING &&
70 (((*addr >= 'A') && (*addr <= 'Z')) ||
71 ((*addr >= 'a') && (*addr <= 'z'))))
72 state |= LETTER;
73 else
74 state |= DELIM;
75 addr++;
76 switch (state /* | INPUT */) {
77 case NAMING | DIGIT:
78 case NAMING | LETTER:
79 *cp++ = addr[-1];
80 continue;
81 case NAMING | DELIM:
82 state = RESET;
83 sdl->sdl_nlen = cp - sdl->sdl_data;
84 continue;
85 case GOTTWO | DIGIT:
86 *cp++ = byte;
87 /* FALLTHROUGH */
88 case RESET | DIGIT:
89 state = GOTONE;
90 byte = new;
91 continue;
92 case GOTONE | DIGIT:
93 state = GOTTWO;
94 byte = new + (byte << 4);
95 continue;
96 default: /* | DELIM */
97 state = RESET;
98 *cp++ = byte;
99 byte = 0;
100 continue;
101 case GOTONE | END:
102 case GOTTWO | END:
103 *cp++ = byte;
104 /* FALLTHROUGH */
105 case RESET | END:
106 break;
107 }
108 break;
109 } while (cp < cplim);
110 sdl->sdl_alen = cp - LLADDR(sdl);
111 new = cp - (char *)sdl;
112 if (new > sizeof(*sdl))
113 sdl->sdl_len = new;
114 return;
115 }
116
117 static const char hexlist[] = "0123456789abcdef";
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 _Static_assert(sizeof(obuf) >= IFNAMSIZ + 20, "obuf is too small");
124 char *out;
125 const u_char *in, *inlim;
126 int namelen, i, rem;
127
128 namelen = (sdl->sdl_nlen <= IFNAMSIZ) ? sdl->sdl_nlen : IFNAMSIZ;
129
130 out = obuf;
131 rem = sizeof(obuf);
132 if (namelen > 0) {
133 bcopy(sdl->sdl_data, out, namelen);
134 out += namelen;
135 rem -= namelen;
136 if (sdl->sdl_alen > 0) {
137 *out++ = ':';
138 rem--;
139 }
140 }
141
142 in = (const u_char *)sdl->sdl_data + sdl->sdl_nlen;
143 inlim = in + sdl->sdl_alen;
144
145 while (in < inlim && rem > 1) {
146 if (in != (const u_char *)sdl->sdl_data + sdl->sdl_nlen) {
147 *out++ = '.';
148 rem--;
149 }
150 i = *in++;
151 if (i > 0xf) {
152 if (rem < 3)
153 break;
154 *out++ = hexlist[i >> 4];
155 *out++ = hexlist[i & 0xf];
156 rem -= 2;
157 } else {
158 if (rem < 2)
159 break;
160 *out++ = hexlist[i];
161 rem--;
162 }
163 }
164 *out = 0;
165 return (obuf);
166 }
167