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 #include <sys/types.h> 37 #include <sys/socket.h> 38 #include <net/if.h> 39 #include <net/if_dl.h> 40 #include <string.h> 41 42 /* States*/ 43 #define NAMING 0 44 #define GOTONE 1 45 #define GOTTWO 2 46 #define RESET 3 47 /* Inputs */ 48 #define DIGIT (4*0) 49 #define END (4*1) 50 #define DELIM (4*2) 51 #define LETTER (4*3) 52 53 void 54 link_addr(const char *addr, struct sockaddr_dl *sdl) 55 { 56 char *cp = sdl->sdl_data; 57 char *cplim = sdl->sdl_len + (char *)sdl; 58 int byte = 0, state = NAMING, new; 59 60 bzero((char *)&sdl->sdl_family, sdl->sdl_len - 1); 61 sdl->sdl_family = AF_LINK; 62 do { 63 state &= ~LETTER; 64 if ((*addr >= '0') && (*addr <= '9')) { 65 new = *addr - '0'; 66 } else if ((*addr >= 'a') && (*addr <= 'f')) { 67 new = *addr - 'a' + 10; 68 } else if ((*addr >= 'A') && (*addr <= 'F')) { 69 new = *addr - 'A' + 10; 70 } else if (*addr == 0) { 71 state |= END; 72 } else if (state == NAMING && 73 (((*addr >= 'A') && (*addr <= 'Z')) || 74 ((*addr >= 'a') && (*addr <= 'z')))) 75 state |= LETTER; 76 else 77 state |= DELIM; 78 addr++; 79 switch (state /* | INPUT */) { 80 case NAMING | DIGIT: 81 case NAMING | LETTER: 82 *cp++ = addr[-1]; 83 continue; 84 case NAMING | DELIM: 85 state = RESET; 86 sdl->sdl_nlen = cp - sdl->sdl_data; 87 continue; 88 case GOTTWO | DIGIT: 89 *cp++ = byte; 90 /* FALLTHROUGH */ 91 case RESET | DIGIT: 92 state = GOTONE; 93 byte = new; 94 continue; 95 case GOTONE | DIGIT: 96 state = GOTTWO; 97 byte = new + (byte << 4); 98 continue; 99 default: /* | DELIM */ 100 state = RESET; 101 *cp++ = byte; 102 byte = 0; 103 continue; 104 case GOTONE | END: 105 case GOTTWO | END: 106 *cp++ = byte; 107 /* FALLTHROUGH */ 108 case RESET | END: 109 break; 110 } 111 break; 112 } while (cp < cplim); 113 sdl->sdl_alen = cp - LLADDR(sdl); 114 new = cp - (char *)sdl; 115 if (new > sizeof(*sdl)) 116 sdl->sdl_len = new; 117 return; 118 } 119 120 static const char hexlist[] = "0123456789abcdef"; 121 122 char * 123 link_ntoa(const struct sockaddr_dl *sdl) 124 { 125 static char obuf[64]; 126 _Static_assert(sizeof(obuf) >= IFNAMSIZ + 20, "obuf is too small"); 127 char *out; 128 const u_char *in, *inlim; 129 int namelen, i, rem; 130 131 namelen = (sdl->sdl_nlen <= IFNAMSIZ) ? sdl->sdl_nlen : IFNAMSIZ; 132 133 out = obuf; 134 rem = sizeof(obuf); 135 if (namelen > 0) { 136 bcopy(sdl->sdl_data, out, namelen); 137 out += namelen; 138 rem -= namelen; 139 if (sdl->sdl_alen > 0) { 140 *out++ = ':'; 141 rem--; 142 } 143 } 144 145 in = (const u_char *)sdl->sdl_data + sdl->sdl_nlen; 146 inlim = in + sdl->sdl_alen; 147 148 while (in < inlim && rem > 1) { 149 if (in != (const u_char *)sdl->sdl_data + sdl->sdl_nlen) { 150 *out++ = '.'; 151 rem--; 152 } 153 i = *in++; 154 if (i > 0xf) { 155 if (rem < 3) 156 break; 157 *out++ = hexlist[i >> 4]; 158 *out++ = hexlist[i & 0xf]; 159 rem -= 2; 160 } else { 161 if (rem < 2) 162 break; 163 *out++ = hexlist[i]; 164 rem--; 165 } 166 } 167 *out = 0; 168 return (obuf); 169 } 170