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 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 * 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