Xray-core/features/routing/dns/context.go
2021-04-09 23:36:36 +08:00

45 lines
1.2 KiB
Go

package dns
//go:generate go run github.com/xtls/xray-core/common/errors/errorgen
import (
"github.com/xtls/xray-core/common/net"
"github.com/xtls/xray-core/features/dns"
"github.com/xtls/xray-core/features/routing"
)
// ResolvableContext is an implementation of routing.Context, with domain resolving capability.
type ResolvableContext struct {
routing.Context
dnsClient dns.Client
resolvedIPs []net.IP
}
// GetTargetIPs overrides original routing.Context's implementation.
func (ctx *ResolvableContext) GetTargetIPs() []net.IP {
if ips := ctx.Context.GetTargetIPs(); len(ips) != 0 {
return ips
}
if len(ctx.resolvedIPs) > 0 {
return ctx.resolvedIPs
}
if domain := ctx.GetTargetDomain(); len(domain) != 0 {
ips, err := ctx.dnsClient.LookupIP(domain)
if err == nil {
ctx.resolvedIPs = ips
return ips
}
newError("failed to resolve ip for ", domain).Base(err).WriteToLog()
}
return nil
}
// ContextWithDNSClient creates a new routing context with domain resolving capability.
// Resolved domain IPs can be retrieved by GetTargetIPs().
func ContextWithDNSClient(ctx routing.Context, client dns.Client) routing.Context {
return &ResolvableContext{Context: ctx, dnsClient: client}
}