1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
6 This file is part of systemd.
8 Copyright 2014 Lennart Poettering
10 systemd is free software; you can redistribute it and/or modify it
11 under the terms of the GNU Lesser General Public License as published by
12 the Free Software Foundation; either version 2.1 of the License, or
13 (at your option) any later version.
15 systemd is distributed in the hope that it will be useful, but
16 WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 Lesser General Public License for more details.
20 You should have received a copy of the GNU Lesser General Public License
21 along with systemd; If not, see <http://www.gnu.org/licenses/>.
24 typedef struct DnsPacketHeader DnsPacketHeader;
25 typedef struct DnsPacket DnsPacket;
30 #include "sparse-endian.h"
32 #include "resolved-dns-rr.h"
34 struct DnsPacketHeader {
43 #define DNS_PACKET_HEADER_SIZE sizeof(DnsPacketHeader)
44 #define DNS_PACKET_SIZE_START 512
48 size_t size, allocated, rindex;
49 Hashmap *names; /* For name compression */
54 static inline uint8_t* DNS_PACKET_DATA(DnsPacket *p) {
61 return ((uint8_t*) p) + ALIGN(sizeof(DnsPacket));
64 #define DNS_PACKET_HEADER(p) ((DnsPacketHeader*) DNS_PACKET_DATA(p))
65 #define DNS_PACKET_ID(p) DNS_PACKET_HEADER(p)->id
66 #define DNS_PACKET_QR(p) ((be16toh(DNS_PACKET_HEADER(p)->flags) >> 15) & 1)
67 #define DNS_PACKET_OPCODE(p) ((be16toh(DNS_PACKET_HEADER(p)->flags) >> 11) & 15)
68 #define DNS_PACKET_RCODE(p) (be16toh(DNS_PACKET_HEADER(p)->flags) & 15)
69 #define DNS_PACKET_QDCOUNT(p) be16toh(DNS_PACKET_HEADER(p)->qdcount)
70 #define DNS_PACKET_ANCOUNT(p) be16toh(DNS_PACKET_HEADER(p)->ancount)
71 #define DNS_PACKET_NSCOUNT(p) be16toh(DNS_PACKET_HEADER(p)->nscount)
72 #define DNS_PACKET_ARCOUNT(p) be16toh(DNS_PACKET_HEADER(p)->arcount)
74 #define DNS_PACKET_MAKE_FLAGS(qr, opcode, aa, tc, rd, ra, ad, cd, rcode) \
75 (((uint16_t) !!qr << 15) | \
76 ((uint16_t) (opcode & 15) << 11) | \
77 ((uint16_t) !!aa << 10) | \
78 ((uint16_t) !!tc << 9) | \
79 ((uint16_t) !!rd << 8) | \
80 ((uint16_t) !!ra << 7) | \
81 ((uint16_t) !!ad << 5) | \
82 ((uint16_t) !!cd << 4) | \
83 ((uint16_t) (rcode & 15)))
86 int dns_packet_new(DnsPacket **p, size_t mtu);
87 int dns_packet_new_query(DnsPacket **p, size_t mtu);
89 DnsPacket *dns_packet_ref(DnsPacket *p);
90 DnsPacket *dns_packet_unref(DnsPacket *p);
92 DEFINE_TRIVIAL_CLEANUP_FUNC(DnsPacket*, dns_packet_unref);
94 int dns_packet_validate(DnsPacket *p);
95 int dns_packet_validate_reply(DnsPacket *p);
97 int dns_packet_append_uint8(DnsPacket *p, uint8_t v, size_t *start);
98 int dns_packet_append_uint16(DnsPacket *p, uint16_t v, size_t *start);
99 int dns_packet_append_string(DnsPacket *p, const char *s, size_t *start);
100 int dns_packet_append_label(DnsPacket *p, const char *s, size_t l, size_t *start);
101 int dns_packet_append_name(DnsPacket *p, const char *name, size_t *start);
102 int dns_packet_append_key(DnsPacket *p, const DnsResourceKey *k, size_t *start);
104 int dns_packet_read(DnsPacket *p, size_t sz, const void **ret, size_t *start);
105 int dns_packet_read_uint8(DnsPacket *p, uint8_t *ret, size_t *start);
106 int dns_packet_read_uint16(DnsPacket *p, uint16_t *ret, size_t *start);
107 int dns_packet_read_uint32(DnsPacket *p, uint32_t *ret, size_t *start);
108 int dns_packet_read_string(DnsPacket *p, char **ret, size_t *start);
109 int dns_packet_read_name(DnsPacket *p, char **ret, size_t *start);
110 int dns_packet_read_key(DnsPacket *p, DnsResourceKey *ret, size_t *start);
111 int dns_packet_read_rr(DnsPacket *p, DnsResourceRecord **ret, size_t *start);
113 int dns_packet_skip_question(DnsPacket *p);
116 DNS_RCODE_SUCCESS = 0,
117 DNS_RCODE_FORMERR = 1,
118 DNS_RCODE_SERVFAIL = 2,
119 DNS_RCODE_NXDOMAIN = 3,
120 DNS_RCODE_NOTIMP = 4,
121 DNS_RCODE_REFUSED = 5,
122 DNS_RCODE_YXDOMAIN = 6,
123 DNS_RCODE_YXRRSET = 7,
124 DNS_RCODE_NXRRSET = 8,
125 DNS_RCODE_NOTAUTH = 9,
126 DNS_RCODE_NOTZONE = 10,
127 DNS_RCODE_BADVERS = 16,
128 DNS_RCODE_BADSIG = 16, /* duplicate value! */
129 DNS_RCODE_BADKEY = 17,
130 DNS_RCODE_BADTIME = 18,
131 DNS_RCODE_BADMODE = 19,
132 DNS_RCODE_BADNAME = 20,
133 DNS_RCODE_BADALG = 21,
134 DNS_RCODE_BADTRUNC = 22,
135 _DNS_RCODE_MAX_DEFINED
138 const char* dns_rcode_to_string(int i) _const_;
139 int dns_rcode_from_string(const char *s) _pure_;