fastdns/record.go at master · phuslu/fastdns · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
package fastdns

import (
	"net"
)

// AppendSRV appends the SRV records to msg.
func (msg *Message) AppendSRV(ttl uint32, srvs []net.SRV) {
	// SRV Records
	for _, srv := range srvs {
		length := 8 + len(srv.Target)
		msg.Raw = EncodeDomain(append(msg.Raw,
			// NAME
			0xc0, 0x0c,
			// TYPE
			0x00, byte(TypeSRV),
			// CLASS
			byte(msg.Question.Class>>8), byte(msg.Question.Class),
			// TTL
			byte(ttl>>24), byte(ttl>>16), byte(ttl>>8), byte(ttl),
			// RDLENGTH
			byte(length>>8), byte(length),
			// PRIOVRITY
			byte(srv.Priority>>8), byte(srv.Priority),
			// WEIGHT
			byte(srv.Weight>>8), byte(srv.Weight),
			// PORT
			byte(srv.Port>>8), byte(srv.Port),
			// RDATA
		), srv.Target)
	}
}

// AppendNS appends the NS records to msg.
func (msg *Message) AppendNS(ttl uint32, nameservers []net.NS) {
	// NS Records
	for _, ns := range nameservers {
		msg.Raw = EncodeDomain(append(msg.Raw,
			// NAME
			0xc0, 0x0c,
			// TYPE
			0x00, byte(TypeNS),
			// CLASS
			byte(msg.Question.Class>>8), byte(msg.Question.Class),
			// TTL
			byte(ttl>>24), byte(ttl>>16), byte(ttl>>8), byte(ttl),
			// RDLENGTH
			0x00, byte(len(ns.Host)+2),
			// RDATA
		), ns.Host)
	}
}

// AppendSOA appends the SOA records to msg.
func (msg *Message) AppendSOA(ttl uint32, mname, rname net.NS, serial, refresh, retry, expire, minimum uint32) {
	length := 2 + len(mname.Host) + 2 + len(rname.Host) + 4 + 4 + 4 + 4 + 4
	msg.Raw = append(msg.Raw,
		// NAME
		0xc0, 0x0c,
		// TYPE
		0x00, byte(TypeSOA),
		// CLASS
		byte(msg.Question.Class>>8), byte(msg.Question.Class),
		// TTL
		byte(ttl>>24), byte(ttl>>16), byte(ttl>>8), byte(ttl),
		// RDLENGTH
		byte(length>>8), byte(length),
	)

	// MNAME
	msg.Raw = EncodeDomain(msg.Raw, mname.Host)
	// RNAME
	msg.Raw = EncodeDomain(msg.Raw, rname.Host)

	msg.Raw = append(msg.Raw,
		// SERIAL
		byte(serial>>24), byte(serial>>16), byte(serial>>8), byte(serial),
		// REFRESH
		byte(refresh>>24), byte(refresh>>16), byte(refresh>>8), byte(refresh),
		// RETRY
		byte(retry>>24), byte(retry>>16), byte(retry>>8), byte(retry),
		// EXPIRE
		byte(expire>>24), byte(expire>>16), byte(expire>>8), byte(expire),
		// MINIMUM
		byte(minimum>>24), byte(minimum>>16), byte(minimum>>8), byte(minimum),
	)
}

// AppendMX appends the MX records to msg.
func (msg *Message) AppendMX(ttl uint32, mxs []net.MX) {
	// MX Records
	for _, mx := range mxs {
		length := 4 + len(mx.Host)
		msg.Raw = EncodeDomain(append(msg.Raw,
			// NAME
			0xc0, 0x0c,
			// TYPE
			0x00, byte(TypeMX),
			// CLASS
			byte(msg.Question.Class>>8), byte(msg.Question.Class),
			// TTL
			byte(ttl>>24), byte(ttl>>16), byte(ttl>>8), byte(ttl),
			// RDLENGTH
			byte(length>>8), byte(length),
			// PRIOVRITY
			byte(mx.Pref>>8), byte(mx.Pref),
			// RDATA
		), mx.Host)
	}
}

// AppendPTR appends the PTR records to msg.
func (msg *Message) AppendPTR(ttl uint32, ptr string) {
	msg.Raw = EncodeDomain(append(msg.Raw,
		// NAME
		0xc0, 0x0c,
		// TYPE
		0x00, byte(TypePTR),
		// CLASS
		byte(msg.Question.Class>>8), byte(msg.Question.Class),
		// TTL
		byte(ttl>>24), byte(ttl>>16), byte(ttl>>8), byte(ttl),
		// RDLENGTH
		00, byte(2+len(ptr)),
		// PTR
	), ptr)
}

// AppendTXT appends the TXT records to msg.
func (msg *Message) AppendTXT(ttl uint32, txt string) {
	length := len(txt) + (len(txt)+0xff)/0x100
	msg.Raw = append(msg.Raw,
		// NAME
		0xc0, 0x0c,
		// TYPE
		0x00, byte(TypeTXT),
		// CLASS
		byte(msg.Question.Class>>8), byte(msg.Question.Class),
		// TTL
		byte(ttl>>24), byte(ttl>>16), byte(ttl>>8), byte(ttl),
		// RDLENGTH
		byte(length>>8), byte(length),
	)

	for len(txt) > 0xff {
		// TXT Length
		msg.Raw = append(msg.Raw, 0xff)
		// TXT
		msg.Raw = append(msg.Raw, txt[:0xff]...)
		txt = txt[0xff:]
	}

	// TXT Length
	msg.Raw = append(msg.Raw, byte(len(txt)))
	// TXT
	msg.Raw = append(msg.Raw, txt...)
}