forked from v2fly/v2ray-core
-
Notifications
You must be signed in to change notification settings - Fork 0
/
server.go
130 lines (110 loc) · 2.85 KB
/
server.go
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
package server
import (
"net"
"sync"
"time"
"v2ray.com/core/app"
"v2ray.com/core/app/dispatcher"
"v2ray.com/core/app/dns"
"v2ray.com/core/common/errors"
"v2ray.com/core/common/log"
v2net "v2ray.com/core/common/net"
"v2ray.com/core/common/serial"
dnsmsg "github.com/miekg/dns"
)
const (
QueryTimeout = time.Second * 8
)
type DomainRecord struct {
A *ARecord
}
type CacheServer struct {
sync.RWMutex
space app.Space
hosts map[string]net.IP
records map[string]*DomainRecord
servers []NameServer
}
func NewCacheServer(space app.Space, config *dns.Config) *CacheServer {
server := &CacheServer{
records: make(map[string]*DomainRecord),
servers: make([]NameServer, len(config.NameServers)),
hosts: config.GetInternalHosts(),
}
space.InitializeApplication(func() error {
if !space.HasApp(dispatcher.APP_ID) {
return errors.New("DNS: Dispatcher is not found in the space.")
}
dispatcher := space.GetApp(dispatcher.APP_ID).(dispatcher.PacketDispatcher)
for idx, destPB := range config.NameServers {
address := destPB.Address.AsAddress()
if address.Family().IsDomain() && address.Domain() == "localhost" {
server.servers[idx] = &LocalNameServer{}
} else {
dest := destPB.AsDestination()
if dest.Network == v2net.Network_Unknown {
dest.Network = v2net.Network_UDP
}
if dest.Network == v2net.Network_UDP {
server.servers[idx] = NewUDPNameServer(dest, dispatcher)
}
}
}
if len(config.NameServers) == 0 {
server.servers = append(server.servers, &LocalNameServer{})
}
return nil
})
return server
}
func (v *CacheServer) Release() {
}
// Private: Visible for testing.
func (v *CacheServer) GetCached(domain string) []net.IP {
v.RLock()
defer v.RUnlock()
if record, found := v.records[domain]; found && record.A.Expire.After(time.Now()) {
return record.A.IPs
}
return nil
}
func (v *CacheServer) Get(domain string) []net.IP {
if ip, found := v.hosts[domain]; found {
return []net.IP{ip}
}
domain = dnsmsg.Fqdn(domain)
ips := v.GetCached(domain)
if ips != nil {
return ips
}
for _, server := range v.servers {
response := server.QueryA(domain)
select {
case a, open := <-response:
if !open || a == nil {
continue
}
v.Lock()
v.records[domain] = &DomainRecord{
A: a,
}
v.Unlock()
log.Debug("DNS: Returning ", len(a.IPs), " IPs for domain ", domain)
return a.IPs
case <-time.After(QueryTimeout):
}
}
log.Debug("DNS: Returning nil for domain ", domain)
return nil
}
type CacheServerFactory struct{}
func (v CacheServerFactory) Create(space app.Space, config interface{}) (app.Application, error) {
server := NewCacheServer(space, config.(*dns.Config))
return server, nil
}
func (v CacheServerFactory) AppId() app.ID {
return dns.APP_ID
}
func init() {
app.RegisterApplicationFactory(serial.GetMessageType(new(dns.Config)), CacheServerFactory{})
}