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 1.14 2020/09/14 08:40:44 florian Exp $ */
18
19 /* RFC2874 */
20
21 #ifndef RDATA_IN_1_A6_28_C
22 #define RDATA_IN_1_A6_28_C
23
24 static inline isc_result_t
totext_in_a6(ARGS_TOTEXT)25 totext_in_a6(ARGS_TOTEXT) {
26 isc_region_t sr, ar;
27 unsigned char addr[16];
28 unsigned char prefixlen;
29 unsigned char octets;
30 unsigned char mask;
31 char buf[sizeof("128")];
32 dns_name_t name;
33 dns_name_t prefix;
34 int sub;
35
36 REQUIRE(rdata->type == dns_rdatatype_a6);
37 REQUIRE(rdata->rdclass == dns_rdataclass_in);
38 REQUIRE(rdata->length != 0);
39
40 dns_rdata_toregion(rdata, &sr);
41 prefixlen = sr.base[0];
42 INSIST(prefixlen <= 128);
43 isc_region_consume(&sr, 1);
44 snprintf(buf, sizeof(buf), "%u", prefixlen);
45 RETERR(isc_str_tobuffer(buf, target));
46 RETERR(isc_str_tobuffer(" ", target));
47
48 if (prefixlen != 128) {
49 octets = prefixlen/8;
50 memset(addr, 0, sizeof(addr));
51 memmove(&addr[octets], sr.base, 16 - octets);
52 mask = 0xff >> (prefixlen % 8);
53 addr[octets] &= mask;
54 ar.base = addr;
55 ar.length = sizeof(addr);
56 RETERR(inet_totext(AF_INET6, &ar, target));
57 isc_region_consume(&sr, 16 - octets);
58 }
59
60 if (prefixlen == 0)
61 return (ISC_R_SUCCESS);
62
63 RETERR(isc_str_tobuffer(" ", target));
64 dns_name_init(&name, NULL);
65 dns_name_init(&prefix, NULL);
66 dns_name_fromregion(&name, &sr);
67 sub = name_prefix(&name, tctx->origin, &prefix);
68 return (dns_name_totext(&prefix, sub, target));
69 }
70
71 static inline isc_result_t
fromwire_in_a6(ARGS_FROMWIRE)72 fromwire_in_a6(ARGS_FROMWIRE) {
73 isc_region_t sr;
74 unsigned char prefixlen;
75 unsigned char octets;
76 unsigned char mask;
77 dns_name_t name;
78
79 REQUIRE(type == dns_rdatatype_a6);
80 REQUIRE(rdclass == dns_rdataclass_in);
81
82 UNUSED(type);
83 UNUSED(rdclass);
84
85 dns_decompress_setmethods(dctx, DNS_COMPRESS_NONE);
86
87 isc_buffer_activeregion(source, &sr);
88 /*
89 * Prefix length.
90 */
91 if (sr.length < 1)
92 return (ISC_R_UNEXPECTEDEND);
93 prefixlen = sr.base[0];
94 if (prefixlen > 128)
95 return (ISC_R_RANGE);
96 isc_region_consume(&sr, 1);
97 RETERR(isc_mem_tobuffer(target, &prefixlen, 1));
98 isc_buffer_forward(source, 1);
99
100 /*
101 * Suffix.
102 */
103 if (prefixlen != 128) {
104 octets = 16 - prefixlen / 8;
105 if (sr.length < octets)
106 return (ISC_R_UNEXPECTEDEND);
107 mask = 0xff >> (prefixlen % 8);
108 sr.base[0] &= mask; /* Ensure pad bits are zero. */
109 RETERR(isc_mem_tobuffer(target, sr.base, octets));
110 isc_buffer_forward(source, octets);
111 }
112
113 if (prefixlen == 0)
114 return (ISC_R_SUCCESS);
115
116 dns_name_init(&name, NULL);
117 return (dns_name_fromwire(&name, source, dctx, options, target));
118 }
119
120 static inline isc_result_t
towire_in_a6(ARGS_TOWIRE)121 towire_in_a6(ARGS_TOWIRE) {
122 isc_region_t sr;
123 dns_name_t name;
124 dns_offsets_t offsets;
125 unsigned char prefixlen;
126 unsigned char octets;
127
128 REQUIRE(rdata->type == dns_rdatatype_a6);
129 REQUIRE(rdata->rdclass == dns_rdataclass_in);
130 REQUIRE(rdata->length != 0);
131
132 dns_compress_setmethods(cctx, DNS_COMPRESS_NONE);
133 dns_rdata_toregion(rdata, &sr);
134 prefixlen = sr.base[0];
135 INSIST(prefixlen <= 128);
136
137 octets = 1 + 16 - prefixlen / 8;
138 RETERR(isc_mem_tobuffer(target, sr.base, octets));
139 isc_region_consume(&sr, octets);
140
141 if (prefixlen == 0)
142 return (ISC_R_SUCCESS);
143
144 dns_name_init(&name, offsets);
145 dns_name_fromregion(&name, &sr);
146 return (dns_name_towire(&name, cctx, target));
147 }
148
149 #endif /* RDATA_IN_1_A6_38_C */
150