From 0f8bd01aadaf6a54528698cba5abadd12ebeafad Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E5=AE=89=E5=AE=B9?= <HystericalDragons@proton.me>
Date: Sat, 26 Apr 2025 14:03:51 +0800
Subject: [PATCH] Report invalid DNS address early

---
 dns/transport/https.go      | 4 +++-
 dns/transport/quic/http3.go | 4 +++-
 dns/transport/quic/quic.go  | 5 ++++-
 dns/transport/tcp.go        | 5 ++++-
 dns/transport/tls.go        | 4 +++-
 dns/transport/udp.go        | 5 ++++-
 6 files changed, 21 insertions(+), 6 deletions(-)

diff --git a/dns/transport/https.go b/dns/transport/https.go
index 1750fd26..6e71dae1 100644
--- a/dns/transport/https.go
+++ b/dns/transport/https.go
@@ -93,7 +93,9 @@ func NewHTTPS(ctx context.Context, logger log.ContextLogger, tag string, options
 		return nil, err
 	}
 	serverAddr := options.DNSServerAddressOptions.Build()
-	if serverAddr.Port == 0 {
+	if !serverAddr.Addr.IsValid() {
+		return nil, E.New("invalid server address: ", serverAddr)
+	} else if serverAddr.Port == 0 {
 		serverAddr.Port = 443
 	}
 	return NewHTTPSRaw(
diff --git a/dns/transport/quic/http3.go b/dns/transport/quic/http3.go
index 0d871741..6d796576 100644
--- a/dns/transport/quic/http3.go
+++ b/dns/transport/quic/http3.go
@@ -89,7 +89,9 @@ func NewHTTP3(ctx context.Context, logger log.ContextLogger, tag string, options
 		return nil, err
 	}
 	serverAddr := options.DNSServerAddressOptions.Build()
-	if serverAddr.Port == 0 {
+	if !serverAddr.Addr.IsValid() {
+		return nil, E.New("invalid server address: ", serverAddr)
+	} else if serverAddr.Port == 0 {
 		serverAddr.Port = 443
 	}
 	return &HTTP3Transport{
diff --git a/dns/transport/quic/quic.go b/dns/transport/quic/quic.go
index 18f8b9fe..f48412a4 100644
--- a/dns/transport/quic/quic.go
+++ b/dns/transport/quic/quic.go
@@ -16,6 +16,7 @@ import (
 	sQUIC "github.com/sagernet/sing-quic"
 	"github.com/sagernet/sing/common"
 	"github.com/sagernet/sing/common/bufio"
+	E "github.com/sagernet/sing/common/exceptions"
 	"github.com/sagernet/sing/common/logger"
 	M "github.com/sagernet/sing/common/metadata"
 	N "github.com/sagernet/sing/common/network"
@@ -55,7 +56,9 @@ func NewQUIC(ctx context.Context, logger log.ContextLogger, tag string, options
 		tlsConfig.SetNextProtos([]string{"doq"})
 	}
 	serverAddr := options.DNSServerAddressOptions.Build()
-	if serverAddr.Port == 0 {
+	if !serverAddr.Addr.IsValid() {
+		return nil, E.New("invalid server address: ", serverAddr)
+	} else if serverAddr.Port == 0 {
 		serverAddr.Port = 853
 	}
 	return &Transport{
diff --git a/dns/transport/tcp.go b/dns/transport/tcp.go
index a814c030..3277c36d 100644
--- a/dns/transport/tcp.go
+++ b/dns/transport/tcp.go
@@ -13,6 +13,7 @@ import (
 	"github.com/sagernet/sing-box/option"
 	"github.com/sagernet/sing/common"
 	"github.com/sagernet/sing/common/buf"
+	E "github.com/sagernet/sing/common/exceptions"
 	M "github.com/sagernet/sing/common/metadata"
 	N "github.com/sagernet/sing/common/network"
 
@@ -37,7 +38,9 @@ func NewTCP(ctx context.Context, logger log.ContextLogger, tag string, options o
 		return nil, err
 	}
 	serverAddr := options.DNSServerAddressOptions.Build()
-	if serverAddr.Port == 0 {
+	if !serverAddr.Addr.IsValid() {
+		return nil, E.New("invalid server address: ", serverAddr)
+	} else if serverAddr.Port == 0 {
 		serverAddr.Port = 53
 	}
 	return &TCPTransport{
diff --git a/dns/transport/tls.go b/dns/transport/tls.go
index a99bf2f7..a584bff8 100644
--- a/dns/transport/tls.go
+++ b/dns/transport/tls.go
@@ -54,7 +54,9 @@ func NewTLS(ctx context.Context, logger log.ContextLogger, tag string, options o
 		return nil, err
 	}
 	serverAddr := options.DNSServerAddressOptions.Build()
-	if serverAddr.Port == 0 {
+	if !serverAddr.Addr.IsValid() {
+		return nil, E.New("invalid server address: ", serverAddr)
+	} else if serverAddr.Port == 0 {
 		serverAddr.Port = 853
 	}
 	return &TLSTransport{
diff --git a/dns/transport/udp.go b/dns/transport/udp.go
index e2ad9db7..d43bc21f 100644
--- a/dns/transport/udp.go
+++ b/dns/transport/udp.go
@@ -13,6 +13,7 @@ import (
 	"github.com/sagernet/sing-box/log"
 	"github.com/sagernet/sing-box/option"
 	"github.com/sagernet/sing/common/buf"
+	E "github.com/sagernet/sing/common/exceptions"
 	"github.com/sagernet/sing/common/logger"
 	M "github.com/sagernet/sing/common/metadata"
 	N "github.com/sagernet/sing/common/network"
@@ -44,7 +45,9 @@ func NewUDP(ctx context.Context, logger log.ContextLogger, tag string, options o
 		return nil, err
 	}
 	serverAddr := options.DNSServerAddressOptions.Build()
-	if serverAddr.Port == 0 {
+	if !serverAddr.Addr.IsValid() {
+		return nil, E.New("invalid server address: ", serverAddr)
+	} else if serverAddr.Port == 0 {
 		serverAddr.Port = 53
 	}
 	return NewUDPRaw(logger, dns.NewTransportAdapterWithRemoteOptions(C.DNSTypeUDP, tag, options), transportDialer, serverAddr), nil