Add dns reverse mapping

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世界 2023-03-23 19:08:48 +08:00
parent c74d3a53d4
commit 52b776b561
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GPG key ID: CD109927C34A63C4
5 changed files with 68 additions and 7 deletions

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@ -10,7 +10,8 @@
"final": "",
"strategy": "",
"disable_cache": false,
"disable_expire": false
"disable_expire": false,
"reverse_mapping": false
}
}
@ -43,4 +44,10 @@ Disable dns cache.
#### disable_expire
Disable dns cache expire.
Disable dns cache expire.
#### reverse_mapping
Stores a reverse mapping of IP addresses after responding to a DNS query in order to provide domain names when routing.
Since this process relies on the act of resolving domain names by an application before making a request, it can be problematic in environments such as macOS, where DNS is proxied and cached by the system.

View file

@ -10,7 +10,8 @@
"final": "",
"strategy": "",
"disable_cache": false,
"disable_expire": false
"disable_expire": false,
"reverse_mapping": false
}
}
@ -43,4 +44,10 @@
#### disable_expire
禁用 DNS 缓存过期。
禁用 DNS 缓存过期。
#### reverse_mapping
在响应 DNS 查询后存储 IP 地址的反向映射以为路由目的提供域名。
由于此过程依赖于应用程序在发出请求之前解析域名的行为,因此在 macOS 等 DNS 由系统代理和缓存的环境中可能会出现问题。

View file

@ -10,9 +10,10 @@ import (
)
type DNSOptions struct {
Servers []DNSServerOptions `json:"servers,omitempty"`
Rules []DNSRule `json:"rules,omitempty"`
Final string `json:"final,omitempty"`
Servers []DNSServerOptions `json:"servers,omitempty"`
Rules []DNSRule `json:"rules,omitempty"`
Final string `json:"final,omitempty"`
ReverseMapping bool `json:"reverse_mapping,omitempty"`
DNSClientOptions
}

View file

@ -69,6 +69,7 @@ type Router struct {
transports []dns.Transport
transportMap map[string]dns.Transport
transportDomainStrategy map[dns.Transport]dns.DomainStrategy
dnsReverseMapping *DNSReverseMapping
interfaceFinder myInterfaceFinder
autoDetectInterface bool
defaultInterface string
@ -237,6 +238,10 @@ func NewRouter(
router.transportMap = transportMap
router.transportDomainStrategy = transportDomainStrategy
if dnsOptions.ReverseMapping {
router.dnsReverseMapping = NewDNSReverseMapping()
}
usePlatformDefaultInterfaceMonitor := platformInterface != nil && platformInterface.UsePlatformDefaultInterfaceMonitor()
needInterfaceMonitor := options.AutoDetectInterface || common.Any(inbounds, func(inbound option.Inbound) bool {
return inbound.HTTPOptions.SetSystemProxy || inbound.MixedOptions.SetSystemProxy || inbound.TunOptions.AutoRoute
@ -631,6 +636,15 @@ func (r *Router) RouteConnection(ctx context.Context, conn net.Conn, metadata ad
buffer.Release()
}
}
if r.dnsReverseMapping != nil && metadata.Domain == "" {
domain, loaded := r.dnsReverseMapping.Query(metadata.Destination.Addr)
if loaded {
metadata.Domain = domain
r.logger.DebugContext(ctx, "found reserve mapped domain: ", metadata.Domain)
}
}
if metadata.Destination.IsFqdn() && dns.DomainStrategy(metadata.InboundOptions.DomainStrategy) != dns.DomainStrategyAsIS {
addresses, err := r.Lookup(adapter.WithContext(ctx, &metadata), metadata.Destination.Fqdn, dns.DomainStrategy(metadata.InboundOptions.DomainStrategy))
if err != nil {

View file

@ -4,17 +4,39 @@ import (
"context"
"net/netip"
"strings"
"time"
"github.com/sagernet/sing-box/adapter"
C "github.com/sagernet/sing-box/constant"
"github.com/sagernet/sing-box/log"
"github.com/sagernet/sing-dns"
"github.com/sagernet/sing/common/cache"
E "github.com/sagernet/sing/common/exceptions"
F "github.com/sagernet/sing/common/format"
M "github.com/sagernet/sing/common/metadata"
mDNS "github.com/miekg/dns"
)
type DNSReverseMapping struct {
cache *cache.LruCache[netip.Addr, string]
}
func NewDNSReverseMapping() *DNSReverseMapping {
return &DNSReverseMapping{
cache: cache.New[netip.Addr, string](),
}
}
func (m *DNSReverseMapping) Save(address netip.Addr, domain string, ttl int) {
m.cache.StoreWithExpire(address, domain, time.Now().Add(time.Duration(ttl)*time.Second))
}
func (m *DNSReverseMapping) Query(address netip.Addr) (string, bool) {
domain, loaded := m.cache.Load(address)
return domain, loaded
}
func (r *Router) matchDNS(ctx context.Context) (context.Context, dns.Transport, dns.DomainStrategy) {
metadata := adapter.ContextFrom(ctx)
if metadata == nil {
@ -69,6 +91,16 @@ func (r *Router) Exchange(ctx context.Context, message *mDNS.Msg) (*mDNS.Msg, er
if len(message.Question) > 0 && response != nil {
LogDNSAnswers(r.dnsLogger, ctx, message.Question[0].Name, response.Answer)
}
if r.dnsReverseMapping != nil && len(message.Question) > 0 && response != nil && len(response.Answer) > 0 {
for _, answer := range response.Answer {
switch record := answer.(type) {
case *mDNS.A:
r.dnsReverseMapping.Save(M.AddrFromIP(record.A), fqdnToDomain(record.Hdr.Name), int(record.Hdr.Ttl))
case *mDNS.AAAA:
r.dnsReverseMapping.Save(M.AddrFromIP(record.AAAA), fqdnToDomain(record.Hdr.Name), int(record.Hdr.Ttl))
}
}
}
return response, err
}