Files
netbird/client/inspect/sni_test.go

110 lines
2.4 KiB
Go

package inspect
import (
"bytes"
"crypto/tls"
"net"
"testing"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
func TestExtractSNI(t *testing.T) {
tests := []struct {
name string
sni string
wantSNI string
wantErr bool
}{
{
name: "standard domain",
sni: "example.com",
wantSNI: "example.com",
},
{
name: "subdomain",
sni: "api.staging.example.com",
wantSNI: "api.staging.example.com",
},
{
name: "mixed case normalized to lowercase",
sni: "Example.COM",
wantSNI: "example.com",
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
clientHello := buildClientHello(t, tt.sni)
sni, err := extractSNI(bytes.NewReader(clientHello))
if tt.wantErr {
require.Error(t, err)
return
}
require.NoError(t, err)
assert.Equal(t, tt.wantSNI, sni.PunycodeString())
})
}
}
func TestExtractSNI_NotTLS(t *testing.T) {
// HTTP request instead of TLS
data := []byte("GET / HTTP/1.1\r\nHost: example.com\r\n\r\n")
_, err := extractSNI(bytes.NewReader(data))
require.Error(t, err)
assert.Contains(t, err.Error(), "not a TLS handshake")
}
func TestExtractSNI_Truncated(t *testing.T) {
// Just the record header, no body
data := []byte{0x16, 0x03, 0x01, 0x00, 0x05}
_, err := extractSNI(bytes.NewReader(data))
require.Error(t, err)
}
func TestExtractSNIFromBytes(t *testing.T) {
clientHello := buildClientHello(t, "test.example.com")
sni, err := extractSNIFromBytes(clientHello)
require.NoError(t, err)
assert.Equal(t, "test.example.com", sni.PunycodeString())
}
// buildClientHello generates a real TLS ClientHello with the given SNI.
func buildClientHello(t *testing.T, serverName string) []byte {
t.Helper()
// Use a pipe to capture the ClientHello bytes
clientConn, serverConn := net.Pipe()
done := make(chan []byte, 1)
go func() {
buf := make([]byte, 4096)
n, _ := serverConn.Read(buf)
done <- buf[:n]
serverConn.Close()
}()
tlsConn := tls.Client(clientConn, &tls.Config{
ServerName: serverName,
InsecureSkipVerify: true,
})
// Trigger the handshake (will fail since server isn't TLS, but we capture the ClientHello)
go func() {
_ = tlsConn.Handshake()
tlsConn.Close()
}()
clientHello := <-done
clientConn.Close()
require.True(t, len(clientHello) > 5, "ClientHello too short")
require.Equal(t, byte(0x16), clientHello[0], "not a TLS handshake record")
return clientHello
}