1 /* $NetBSD: dl_print.c,v 1.8 2021/05/27 13:40:38 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 2014 The NetBSD Foundation, Inc. 5 * 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 * 16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 #include <sys/cdefs.h> 29 #include <sys/types.h> 30 31 #ifdef _KERNEL 32 __KERNEL_RCSID(0, "$NetBSD: dl_print.c,v 1.8 2021/05/27 13:40:38 christos Exp $"); 33 #include <sys/systm.h> 34 #else 35 __RCSID("$NetBSD: dl_print.c,v 1.8 2021/05/27 13:40:38 christos Exp $"); 36 #include <stdio.h> 37 static const char hexdigits[] = "0123456789abcdef"; 38 #endif 39 #include <net/if_dl.h> 40 41 static int 42 lla_snprintf1(char *dst, size_t dst_len, const void *src, size_t src_len) 43 { 44 char *dp; 45 const uint8_t *sp, *ep; 46 47 dp = dst; 48 sp = (const uint8_t *)src; 49 ep = sp + src_len; 50 while (sp < ep) { 51 if (dst_len-- == 0) 52 break; 53 *dp++ = hexdigits[(*sp) >> 4]; 54 if (dst_len-- == 0) 55 break; 56 *dp++ = hexdigits[(*sp++) & 0xf]; 57 if (dst_len-- == 0) 58 break; 59 *dp++ = ':'; 60 } 61 if (dp != dst) 62 *--dp = '\0'; 63 64 return src_len ? (int)(src_len * 3) - 1 : 0; 65 } 66 67 char * 68 lla_snprintf(char *dst, size_t dst_len, const void *src, size_t src_len) 69 { 70 (void)lla_snprintf1(dst, dst_len, src, src_len); 71 return dst; 72 } 73 74 #define clip(a, b) ((a) > (size_t)(b) ? (a) - (size_t)(b) : 0) 75 76 int 77 dl_print(char *buf, size_t len, const struct dl_addr *dl) 78 { 79 int l = snprintf(buf, len, "%.*s/%hhu#", 80 (int)dl->dl_nlen, dl->dl_data, dl->dl_type); 81 if (l == -1) 82 return l; 83 int ll = lla_snprintf1(buf + l, clip(len, l), 84 dl->dl_data + dl->dl_nlen, dl->dl_alen); 85 if (ll == -1) 86 return ll; 87 88 return ll + l; 89 } 90 91 int 92 sdl_print(char *buf, size_t len, const void *v) 93 { 94 const struct sockaddr_dl *sdl = v; 95 96 if (sdl->sdl_slen == 0 && sdl->sdl_nlen == 0 && sdl->sdl_alen == 0) 97 return snprintf(buf, len, "link#%hu", sdl->sdl_index); 98 99 if (len > 0) { 100 buf[0] = '['; 101 len--; 102 } 103 int l = dl_print(buf + 1, len, &sdl->sdl_addr); 104 if (l == -1) 105 return l; 106 l++; 107 len++; 108 int ll = snprintf(buf + l, clip(len, l), "]:%hu", sdl->sdl_index); 109 if (ll == -1) 110 return ll; 111 return ll + l; 112 } 113