commit 18e3b47c0740a3dd5da812384cdde715dbd52ccf
Author: afonso <afonso@francof.net>
Date:   Wed Feb 26 17:55:14 2025 +0000

    Do53 and DoH (POST) basic queries implemented

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..30f3f28
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,17 @@
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, built with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# Dependency directories (remove the comment below to include it)
+# vendor/
+
+**/tls-key-log.txt
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..31d7daf
--- /dev/null
+++ b/README.md
@@ -0,0 +1,3 @@
+# DNS Resolver
+
+A DNS resolver supporting multiple protocols including DoH, DoT, DoQ, DNSSEC, ODoH, and DNSCrypt.
diff --git a/cmd/resolver/main.go b/cmd/resolver/main.go
new file mode 100644
index 0000000..2731df6
--- /dev/null
+++ b/cmd/resolver/main.go
@@ -0,0 +1,78 @@
+package main
+
+import (
+	"log"
+
+	"github.com/afonsofrancof/sdns-perf/internal/protocols/do53"
+	"github.com/afonsofrancof/sdns-perf/internal/protocols/doh"
+	"github.com/alecthomas/kong"
+)
+
+type CommonFlags struct {
+	DomainName string `help:"Domain name to resolve" arg:"" required:""`
+	QueryType  string `help:"Query type" enum:"A,AAAA,MX,TXT,NS,CNAME,SOA,PTR" default:"A"`
+	Server     string `help:"DNS server to use"`
+	DNSSEC     bool   `help:"Enable DNSSEC validation"`
+}
+
+type DoHCmd struct {
+	CommonFlags `embed:""`
+	HTTP3       bool   `help:"Use HTTP/3" name:"http3"`
+	Path        string `help:"The HTTP path for the POST request" name:"path" required:""`
+	Proxy       string `help:"The Proxy to use with ODoH"`
+}
+
+type DoTCmd struct {
+	CommonFlags
+}
+
+type DoQCmd struct {
+	CommonFlags
+}
+
+type Do53Cmd struct {
+	CommonFlags
+}
+
+var cli struct {
+	Verbose bool `help:"Enable verbose logging" short:"v"`
+
+	DoH  DoHCmd  `cmd:"doh" help:"Query using DNS-over-HTTPS" name:"doh"`
+	DoT  DoTCmd  `cmd:"dot" help:"Query using DNS-over-TLS" name:"dot"`
+	DoQ  DoQCmd  `cmd:"doq" help:"Query using DNS-over-QUIC" name:"doq"`
+	Do53 Do53Cmd `cmd:"doq" help:"Query using plain DNS over UDP" name:"do53"`
+}
+
+func (c *Do53Cmd) Run() error {
+	return do53.Run(c.DomainName, c.QueryType, c.Server, c.DNSSEC)
+}
+
+func (c *DoHCmd) Run() error {
+	return doh.Run(c.DomainName, c.QueryType, c.Server, c.Path,c.Proxy, c.DNSSEC)
+}
+
+func (c *DoTCmd) Run() error {
+	// TODO: Implement DoT query
+	return nil
+}
+
+func (c *DoQCmd) Run() error {
+	// TODO: Implement DoQ query
+	return nil
+}
+
+func main() {
+	ctx := kong.Parse(&cli,
+		kong.Name("dns-go"),
+		kong.Description("A DNS resolver supporting DoH, DoT, and DoQ protocols"),
+		kong.UsageOnError(),
+		kong.ConfigureHelp(kong.HelpOptions{
+			Compact: true,
+			Summary: true,
+		}))
+
+	err := ctx.Run()
+	if err != nil {
+		log.Fatalf("Error: %v", err)
+	}
+}
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..7b1813b
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,8 @@
+module github.com/afonsofrancof/sdns-perf
+
+go 1.24.0
+
+require (
+	github.com/alecthomas/kong v1.8.1
+	golang.org/x/net v0.35.0
+)
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..f14bc2b
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,10 @@
+github.com/alecthomas/assert/v2 v2.11.0 h1:2Q9r3ki8+JYXvGsDyBXwH3LcJ+WK5D0gc5E8vS6K3D0=
+github.com/alecthomas/assert/v2 v2.11.0/go.mod h1:Bze95FyfUr7x34QZrjL+XP+0qgp/zg8yS+TtBj1WA3k=
+github.com/alecthomas/kong v1.8.1 h1:6aamvWBE/REnR/BCq10EcozmcpUPc5aGI1lPAWdB0EE=
+github.com/alecthomas/kong v1.8.1/go.mod h1:p2vqieVMeTAnaC83txKtXe8FLke2X07aruPWXyMPQrU=
+github.com/alecthomas/repr v0.4.0 h1:GhI2A8MACjfegCPVq9f1FLvIBS+DrQ2KQBFZP1iFzXc=
+github.com/alecthomas/repr v0.4.0/go.mod h1:Fr0507jx4eOXV7AlPV6AVZLYrLIuIeSOWtW57eE/O/4=
+github.com/hexops/gotextdiff v1.0.3 h1:gitA9+qJrrTCsiCl7+kh75nPqQt1cx4ZkudSTLoUqJM=
+github.com/hexops/gotextdiff v1.0.3/go.mod h1:pSWU5MAI3yDq+fZBTazCSJysOMbxWL1BSow5/V2vxeg=
+golang.org/x/net v0.35.0 h1:T5GQRQb2y08kTAByq9L4/bz8cipCdA8FbRTXewonqY8=
+golang.org/x/net v0.35.0/go.mod h1:EglIi67kWsHKlRzzVMUD93VMSWGFOMSZgxFjparz1Qk=
diff --git a/internal/protocols/dnscrypt/dnscrypt.go b/internal/protocols/dnscrypt/dnscrypt.go
new file mode 100644
index 0000000..9939b27
--- /dev/null
+++ b/internal/protocols/dnscrypt/dnscrypt.go
@@ -0,0 +1,3 @@
+package dnscrypt
+
+// DNSCrypt resolver implementation
diff --git a/internal/protocols/dnssec/dnssec.go b/internal/protocols/dnssec/dnssec.go
new file mode 100644
index 0000000..fb852f6
--- /dev/null
+++ b/internal/protocols/dnssec/dnssec.go
@@ -0,0 +1,3 @@
+package dnssec
+
+// DNSSEC resolver implementation
diff --git a/internal/protocols/do53/do53.go b/internal/protocols/do53/do53.go
new file mode 100644
index 0000000..8728edd
--- /dev/null
+++ b/internal/protocols/do53/do53.go
@@ -0,0 +1,63 @@
+package do53
+
+import (
+	"fmt"
+	"net"
+
+	"golang.org/x/net/dns/dnsmessage"
+)
+
+func Run(domain, queryType, dest string, dnssec bool) error {
+
+	message, err := MakeDNSMessage(domain, queryType)
+	if err != nil {
+		return err
+	}
+
+	udpAddr, err := net.ResolveUDPAddr("udp", dest)
+	if err != nil {
+		return fmt.Errorf("failed to resolve UDP address: %v", err)
+	}
+
+	udpConn, err := net.DialUDP("udp", nil, udpAddr)
+	if err != nil {
+		return fmt.Errorf("failed to dial UDP connection: %v", err)
+	}
+	defer udpConn.Close()
+
+	_, err = udpConn.Write(message)
+	if err != nil {
+		return fmt.Errorf("failed to send DNS query: %v", err)
+	}
+
+	buf := make([]byte, 4096)
+	n, err := udpConn.Read(buf)
+	if err != nil {
+		return fmt.Errorf("failed to read DNS response: %v", err)
+	}
+
+	var parser dnsmessage.Parser
+	_, err = parser.Start(buf[:n])
+	if err != nil {
+		return fmt.Errorf("failed to parse DNS response: %v", err)
+	}
+
+	// TODO: Check if the response had no errors or TD bit set
+
+	err = parser.SkipAllQuestions()
+	if err != nil {
+		return fmt.Errorf("failed to skip questions: %v", err)
+	}
+
+	answers, err := parser.AllAnswers()
+	if err != nil {
+		return err
+	}
+
+	for _, answer := range answers {
+		fmt.Println(answer.GoString())
+	}
+
+	return nil
+}
+
diff --git a/internal/protocols/do53/packet.go b/internal/protocols/do53/packet.go
new file mode 100644
index 0000000..d287218
--- /dev/null
+++ b/internal/protocols/do53/packet.go
@@ -0,0 +1,60 @@
+package do53
+
+import (
+	"fmt"
+
+	"golang.org/x/net/dns/dnsmessage"
+)
+
+func MakeDNSMessage(domain string, queryType string) ([]byte, error) {
+	messageHeader := dnsmessage.Header{
+		ID:               1234, // FIX: Use a random ID
+		Response:         false,
+		OpCode:           dnsmessage.OpCode(0),
+		RecursionDesired: true,
+	}
+
+	messageBuilder := dnsmessage.NewBuilder(nil, messageHeader)
+	queryName, err := dnsmessage.NewName(domain)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create query name: %v", err)
+	}
+
+	// Determine query type
+	var queryTypeValue dnsmessage.Type
+	switch queryType {
+	case "A":
+		queryTypeValue = dnsmessage.TypeA
+	case "AAAA":
+		queryTypeValue = dnsmessage.TypeAAAA
+	case "MX":
+		queryTypeValue = dnsmessage.TypeMX
+	case "CNAME":
+		queryTypeValue = dnsmessage.TypeCNAME
+	case "TXT":
+		queryTypeValue = dnsmessage.TypeTXT
+	default:
+		queryTypeValue = dnsmessage.TypeA
+	}
+
+	messageQuestion := dnsmessage.Question{
+		Name:  queryName,
+		Type:  queryTypeValue,
+		Class: dnsmessage.ClassINET,
+	}
+
+	err = messageBuilder.StartQuestions()
+	if err != nil {
+		return nil, err
+	}
+	err = messageBuilder.Question(messageQuestion)
+	if err != nil {
+		return nil, fmt.Errorf("failed to add question: %v", err)
+	}
+
+	message, err := messageBuilder.Finish()
+	if err != nil {
+		return nil, fmt.Errorf("failed to build message: %v", err)
+	}
+	return message, nil
+}
diff --git a/internal/protocols/doh/doh.go b/internal/protocols/doh/doh.go
new file mode 100644
index 0000000..915bac5
--- /dev/null
+++ b/internal/protocols/doh/doh.go
@@ -0,0 +1,148 @@
+package doh
+
+import (
+	"bufio"
+	"bytes"
+	"crypto/tls"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"os"
+
+	"github.com/afonsofrancof/sdns-perf/internal/protocols/do53"
+	"golang.org/x/net/dns/dnsmessage"
+)
+
+func Run(domain, queryType, server, path, proxy string, dnssec bool) error {
+
+	DNSMessage, err := do53.MakeDNSMessage(domain, queryType)
+	if err != nil {
+		return err
+	}
+
+	// Step 1 - Establish a TCP Connection
+	tcpConn, err := net.Dial("tcp", server)
+	if err != nil {
+		return fmt.Errorf("failed to establish TCP connection: %v", err)
+	}
+	defer tcpConn.Close()
+
+	// Step 2 - Upgrade it to a TLS Connection
+
+	// Temporary keylog file to allow traffic inspection
+	keyLogFile, err := os.OpenFile(
+		"tls-key-log.txt",
+		os.O_APPEND|os.O_CREATE|os.O_WRONLY,
+		0600,
+	)
+	if err != nil {
+		return fmt.Errorf("failed opening key log file: %v", err)
+	}
+	defer keyLogFile.Close()
+
+	tlsConfig := &tls.Config{
+		InsecureSkipVerify: true,
+		MinVersion:         tls.VersionTLS12,
+		KeyLogWriter:       keyLogFile,
+	}
+
+	tlsConn := tls.Client(tcpConn, tlsConfig)
+	err = tlsConn.Handshake()
+	if err != nil {
+		return fmt.Errorf("failed to execute the TLS handshake: %v", err)
+	}
+	defer tlsConn.Close()
+
+	// Step 3 - Create an HTTP request with the do53 message in the body
+	httpReq, err := http.NewRequest("POST", "https://"+server+"/"+path, bytes.NewBuffer(DNSMessage))
+	if err != nil {
+		return fmt.Errorf("failed to create HTTP request: %v", err)
+	}
+	httpReq.Header.Add("Content-Type", "application/dns-message")
+	httpReq.Header.Set("Accept", "application/dns-message")
+
+	err = httpReq.Write(tlsConn)
+	if err != nil {
+		return fmt.Errorf("failed writing HTTP request: %v", err)
+	}
+
+	reader := bufio.NewReader(tlsConn)
+	resp, err := http.ReadResponse(reader, httpReq)
+	if err != nil {
+		return fmt.Errorf("failed reading HTTP response: %v", err)
+	}
+	defer resp.Body.Close()
+
+	responseBody := make([]byte, 4096)
+	n, err := resp.Body.Read(responseBody)
+	if err != nil && err != io.EOF {
+		return fmt.Errorf("failed reading response body: %v", err)
+	}
+
+	// Parse the response
+	var parser dnsmessage.Parser
+	header, err := parser.Start(responseBody[:n])
+	if err != nil {
+		return fmt.Errorf("failed to parse DNS response: %v", err)
+	}
+
+	fmt.Printf("DNS Response Header:\n")
+	fmt.Printf("  ID: %d\n", header.ID)
+	fmt.Printf("  Response: %v\n", header.Response)
+	fmt.Printf("  RCode: %v\n", header.RCode)
+
+	// Skip all questions before reading answers
+	err = parser.SkipAllQuestions()
+	if err != nil {
+		return fmt.Errorf("failed to skip questions: %v", err)
+	}
+
+	// Parse answers
+	fmt.Printf("\nAnswers:\n")
+	answers, err := parser.AllAnswers()
+
+	for i, answer := range answers {
+
+		if err != nil {
+			return fmt.Errorf("failed to parse answer %d: %v", i, err)
+		}
+
+		fmt.Printf("  Answer %d:\n", i+1)
+		fmt.Printf("    Name: %v\n", answer.Header.Name)
+		fmt.Printf("    Type: %v\n", answer.Header.Type)
+		fmt.Printf("    TTL: %v seconds\n", answer.Header.TTL)
+
+		// Handle different record types
+		switch answer.Header.Type {
+		case dnsmessage.TypeA:
+			if r, ok := answer.Body.(*dnsmessage.AResource); ok {
+				fmt.Printf("    IPv4: %d.%d.%d.%d\n", r.A[0], r.A[1], r.A[2], r.A[3])
+			}
+		case dnsmessage.TypeAAAA:
+			if r, ok := answer.Body.(*dnsmessage.AAAAResource); ok {
+				ip := r.AAAA
+				fmt.Printf("    IPv6: %02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x\n",
+					ip[0], ip[1], ip[2], ip[3], ip[4], ip[5], ip[6], ip[7],
+					ip[8], ip[9], ip[10], ip[11], ip[12], ip[13], ip[14], ip[15])
+			}
+		case dnsmessage.TypeCNAME:
+			if r, ok := answer.Body.(*dnsmessage.CNAMEResource); ok {
+				fmt.Printf("    CNAME: %v\n", r.CNAME)
+			}
+		case dnsmessage.TypeMX:
+			if r, ok := answer.Body.(*dnsmessage.MXResource); ok {
+				fmt.Printf("    Preference: %v\n", r.Pref)
+				fmt.Printf("    MX: %v\n", r.MX)
+			}
+		case dnsmessage.TypeTXT:
+			if r, ok := answer.Body.(*dnsmessage.TXTResource); ok {
+				fmt.Printf("    TXT: %v\n", r.TXT)
+			}
+		default:
+			fmt.Printf("    [Unsupported record type]\n")
+		}
+	}
+
+	return nil
+}
diff --git a/internal/protocols/doq/doq.go b/internal/protocols/doq/doq.go
new file mode 100644
index 0000000..123b02c
--- /dev/null
+++ b/internal/protocols/doq/doq.go
@@ -0,0 +1,3 @@
+package doq
+
+// DoQ (DNS over QUIC) resolver implementation
diff --git a/internal/protocols/dot/dot.go b/internal/protocols/dot/dot.go
new file mode 100644
index 0000000..d1f5d05
--- /dev/null
+++ b/internal/protocols/dot/dot.go
@@ -0,0 +1,3 @@
+package dot
+
+// DoT (DNS over TLS) resolver implementation