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 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 * 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