1 /* 2 * Copyright (C) Internet Systems Consortium, Inc. ("ISC") 3 * 4 * Permission to use, copy, modify, and/or distribute this software for any 5 * purpose with or without fee is hereby granted, provided that the above 6 * copyright notice and this permission notice appear in all copies. 7 * 8 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH 9 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY 10 * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, 11 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 12 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE 13 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR 14 * PERFORMANCE OF THIS SOFTWARE. 15 */ 16 17 /* $Id: a6_38.c,v 1.12 2020/02/26 18:47:59 florian Exp $ */ 18 19 /* RFC2874 */ 20 21 #ifndef RDATA_IN_1_A6_28_C 22 #define RDATA_IN_1_A6_28_C 23 24 #include <isc/net.h> 25 26 static inline isc_result_t 27 totext_in_a6(ARGS_TOTEXT) { 28 isc_region_t sr, ar; 29 unsigned char addr[16]; 30 unsigned char prefixlen; 31 unsigned char octets; 32 unsigned char mask; 33 char buf[sizeof("128")]; 34 dns_name_t name; 35 dns_name_t prefix; 36 isc_boolean_t sub; 37 38 REQUIRE(rdata->type == dns_rdatatype_a6); 39 REQUIRE(rdata->rdclass == dns_rdataclass_in); 40 REQUIRE(rdata->length != 0); 41 42 dns_rdata_toregion(rdata, &sr); 43 prefixlen = sr.base[0]; 44 INSIST(prefixlen <= 128); 45 isc_region_consume(&sr, 1); 46 snprintf(buf, sizeof(buf), "%u", prefixlen); 47 RETERR(isc_str_tobuffer(buf, target)); 48 RETERR(isc_str_tobuffer(" ", target)); 49 50 if (prefixlen != 128) { 51 octets = prefixlen/8; 52 memset(addr, 0, sizeof(addr)); 53 memmove(&addr[octets], sr.base, 16 - octets); 54 mask = 0xff >> (prefixlen % 8); 55 addr[octets] &= mask; 56 ar.base = addr; 57 ar.length = sizeof(addr); 58 RETERR(inet_totext(AF_INET6, &ar, target)); 59 isc_region_consume(&sr, 16 - octets); 60 } 61 62 if (prefixlen == 0) 63 return (ISC_R_SUCCESS); 64 65 RETERR(isc_str_tobuffer(" ", target)); 66 dns_name_init(&name, NULL); 67 dns_name_init(&prefix, NULL); 68 dns_name_fromregion(&name, &sr); 69 sub = name_prefix(&name, tctx->origin, &prefix); 70 return (dns_name_totext(&prefix, sub, target)); 71 } 72 73 static inline isc_result_t 74 fromwire_in_a6(ARGS_FROMWIRE) { 75 isc_region_t sr; 76 unsigned char prefixlen; 77 unsigned char octets; 78 unsigned char mask; 79 dns_name_t name; 80 81 REQUIRE(type == dns_rdatatype_a6); 82 REQUIRE(rdclass == dns_rdataclass_in); 83 84 UNUSED(type); 85 UNUSED(rdclass); 86 87 dns_decompress_setmethods(dctx, DNS_COMPRESS_NONE); 88 89 isc_buffer_activeregion(source, &sr); 90 /* 91 * Prefix length. 92 */ 93 if (sr.length < 1) 94 return (ISC_R_UNEXPECTEDEND); 95 prefixlen = sr.base[0]; 96 if (prefixlen > 128) 97 return (ISC_R_RANGE); 98 isc_region_consume(&sr, 1); 99 RETERR(isc_mem_tobuffer(target, &prefixlen, 1)); 100 isc_buffer_forward(source, 1); 101 102 /* 103 * Suffix. 104 */ 105 if (prefixlen != 128) { 106 octets = 16 - prefixlen / 8; 107 if (sr.length < octets) 108 return (ISC_R_UNEXPECTEDEND); 109 mask = 0xff >> (prefixlen % 8); 110 sr.base[0] &= mask; /* Ensure pad bits are zero. */ 111 RETERR(isc_mem_tobuffer(target, sr.base, octets)); 112 isc_buffer_forward(source, octets); 113 } 114 115 if (prefixlen == 0) 116 return (ISC_R_SUCCESS); 117 118 dns_name_init(&name, NULL); 119 return (dns_name_fromwire(&name, source, dctx, options, target)); 120 } 121 122 static inline isc_result_t 123 towire_in_a6(ARGS_TOWIRE) { 124 isc_region_t sr; 125 dns_name_t name; 126 dns_offsets_t offsets; 127 unsigned char prefixlen; 128 unsigned char octets; 129 130 REQUIRE(rdata->type == dns_rdatatype_a6); 131 REQUIRE(rdata->rdclass == dns_rdataclass_in); 132 REQUIRE(rdata->length != 0); 133 134 dns_compress_setmethods(cctx, DNS_COMPRESS_NONE); 135 dns_rdata_toregion(rdata, &sr); 136 prefixlen = sr.base[0]; 137 INSIST(prefixlen <= 128); 138 139 octets = 1 + 16 - prefixlen / 8; 140 RETERR(isc_mem_tobuffer(target, sr.base, octets)); 141 isc_region_consume(&sr, octets); 142 143 if (prefixlen == 0) 144 return (ISC_R_SUCCESS); 145 146 dns_name_init(&name, offsets); 147 dns_name_fromregion(&name, &sr); 148 return (dns_name_towire(&name, cctx, target)); 149 } 150 151 #endif /* RDATA_IN_1_A6_38_C */ 152