Switch to new test harness

protocol/detect_http.go

@@ -25,7 +25,6 @@ func detectHTTPRequest(dir Direction, data []byte, srcPort, dstPort int) (proto
 		confidence = -.1
 	}
 
-	if Strict {
 	var (
 		b = append(data, '\r', '\n')
 		r = bufio.NewReader(bytes.NewReader(b))
@@ -40,6 +39,8 @@ func detectHTTPRequest(dir Direction, data []byte, srcPort, dstPort int) (proto
 			},
 		}, confidence + .85
 	}
+
+	if Strict {
 		return nil, 0
 	}
 

protocol/detect_http_test.go

@@ -1,7 +1,6 @@
 package protocol
 
 import (
-	"errors"
 	"testing"
 )
 
@@ -17,6 +16,32 @@ func TestDetectHTTPRequest(t *testing.T) {
 	// An invalid HTTP request
 	sshBanner := []byte("SSH-2.0-OpenSSH_8.9p1 Ubuntu-3ubuntu0.4\r\n")
 
+	tests := []*testCase{
+		{
+			Name:           "HTTP/1.0 GET",
+			Direction:      Client,
+			Data:           http10Request,
+			DstPort:        80,
+			WantProto:      ProtocolHTTP,
+			WantConfidence: .95,
+		},
+		{
+			Name:           "HTTP/1.1 GET",
+			Direction:      Client,
+			Data:           getRequest,
+			DstPort:        80,
+			WantProto:      ProtocolHTTP,
+			WantConfidence: .95,
+		},
+		{
+			Name:      "Invalid SSH",
+			Direction: Client,
+			Data:      sshBanner,
+			DstPort:   80,
+			WantError: ErrUnknown,
+		},
+	}
+
 	defer func() { Strict = false }()
 	for _, strict := range []bool{false, true} {
 		Strict = strict
@@ -27,40 +52,7 @@ func TestDetectHTTPRequest(t *testing.T) {
 		}
 
 		t.Run(name, func(t *testing.T) {
-			t.Run("HTTP/1.0 GET", func(t *testing.T) {
+			testRunner(t, tests)
-				p, c, err := Detect(Client, http10Request, 1234, 80)
-				if err != nil {
-					t.Fatal(err)
-					return
-				}
-				t.Logf("detected %s version %s confidence %g%%", p.Name, p.Version, c*100)
-				if p.Name != ProtocolHTTP {
-					t.Fatalf("expected http protocol, got %s", p.Name)
-					return
-				}
-			})
-
-			t.Run("HTTP/1.1 GET", func(t *testing.T) {
-				p, c, err := Detect(Client, getRequest, 1234, 80)
-				if err != nil {
-					t.Fatal(err)
-					return
-				}
-				t.Logf("detected %s version %s confidence %g%%", p.Name, p.Version, c*100)
-				if p.Name != ProtocolHTTP {
-					t.Fatalf("expected http protocol, got %s", p.Name)
-					return
-				}
-			})
-
-			t.Run("Invalid SSH", func(t *testing.T) {
-				_, _, err := Detect(Server, sshBanner, 1234, 22)
-				if !errors.Is(err, ErrUnknown) {
-					t.Fatalf("expected unknown format, got error %T: %q", err, err)
-				} else {
-					t.Logf("error %q, as expected", err)
-				}
-			})
 		})
 	}
 }
@@ -83,72 +75,67 @@ func TestDetectHTTPResponse(t *testing.T) {
 	// An invalid banner (SSH)
 	sshBanner := []byte("SSH-2.0-OpenSSH_8.9p1 Ubuntu-3ubuntu0.4\r\n")
 
+	tests := []*testCase{
+		{
+			Name:      "HTTP/1.0 403",
+			Direction: Server,
+			Data:      http10Response,
+			SrcPort:   80,
+			WantProto: ProtocolHTTP,
+		},
+		{
+			Name:      "HTTP/1.1 200",
+			Direction: Server,
+			Data:      responseOK,
+			SrcPort:   80,
+			WantProto: ProtocolHTTP,
+		},
+		{
+			Name:      "HTTP/1.1 404",
+			Direction: Server,
+			Data:      responseNotFound,
+			SrcPort:   80,
+			WantProto: ProtocolHTTP,
+		},
+		{
+			Name:      "Invalid HTTP/1.1 GET",
+			Direction: Server,
+			Data:      getRequest,
+			SrcPort:   80,
+			WantError: ErrUnknown,
+		},
+		{
+			Name:      "Invalid SSH",
+			Direction: Server,
+			Data:      sshBanner,
+			SrcPort:   80,
+			WantError: ErrUnknown,
+		},
+	}
+
 	defer func() { Strict = false }()
 	for _, strict := range []bool{false, true} {
 		Strict = strict
 
-		name := "loose"
+		var name string
 		if strict {
 			name = "strict"
+			for _, test := range tests {
+				if test.WantError == nil {
+					test.WantConfidence = .95
+				}
+			}
+		} else {
+			name = "loose"
+			for _, test := range tests {
+				if test.WantError == nil {
+					test.WantConfidence = .85
+				}
+			}
 		}
 
 		t.Run(name, func(t *testing.T) {
-			t.Run("HTTP/1.0 403", func(t *testing.T) {
+			testRunner(t, tests)
-				p, c, err := Detect(Server, http10Response, 80, 1234)
-				if err != nil {
-					t.Fatal(err)
-					return
-				}
-				t.Logf("detected %s version %s confidence %g%%", p.Name, p.Version, c*100)
-				if p.Name != ProtocolHTTP {
-					t.Fatalf("expected http protocol, got %s", p.Name)
-					return
-				}
-			})
-
-			t.Run("HTTP/1.1 200", func(t *testing.T) {
-				p, c, err := Detect(Server, responseOK, 80, 1234)
-				if err != nil {
-					t.Fatal(err)
-					return
-				}
-				t.Logf("detected %s version %s confidence %g%%", p.Name, p.Version, c*100)
-				if p.Name != ProtocolHTTP {
-					t.Fatalf("expected http protocol, got %s", p.Name)
-					return
-				}
-			})
-
-			t.Run("HTTP/1.1 404", func(t *testing.T) {
-				p, c, err := Detect(Server, responseNotFound, 80, 1234)
-				if err != nil {
-					t.Fatal(err)
-					return
-				}
-				t.Logf("detected %s version %s confidence %g%%", p.Name, p.Version, c*100)
-				if p.Name != ProtocolHTTP {
-					t.Fatalf("expected http protocol, got %s", p.Name)
-					return
-				}
-			})
-
-			t.Run("Invalid HTTP/1.1 GET", func(t *testing.T) {
-				_, _, err := Detect(Server, getRequest, 1234, 80)
-				if !errors.Is(err, ErrUnknown) {
-					t.Fatalf("expected unknown format, got error %T: %q", err, err)
-				} else {
-					t.Logf("error %q, as expected", err)
-				}
-			})
-
-			t.Run("Invalid SSH", func(t *testing.T) {
-				_, _, err := Detect(Server, sshBanner, 22, 1234)
-				if !errors.Is(err, ErrUnknown) {
-					t.Fatalf("expected unknown format, got error %T: %q", err, err)
-				} else {
-					t.Logf("error %q, as expected", err)
-				}
-			})
 		})
 	}
 }

protocol/detect_mysql_test.go

@@ -1,7 +1,6 @@
 package protocol
 
 import (
-	"errors"
 	"testing"
 )
 
@@ -14,7 +13,8 @@ func TestDetectMySQL(t *testing.T) {
 		0x04, 0x5a, 0x56, 0x5f, 0x3e, 0x6e, 0x76, 0x27, 0x00, 0xff, 0xff, 0xff,
 		0x02, 0x00, 0xff, 0xc7, 0x15, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 		0x00, 0x00, 0x00, 0x63, 0x61, 0x63, 0x68, 0x69, 0x6e, 0x67, 0x5f, 0x73,
-		0x68, 0x61, 0x32, 0x5f, 0x70, 0x61, 0x73, 0x73, 0x77, 0x6f, 0x72, 0x64, 0x00,
+		0x68, 0x61, 0x32, 0x5f, 0x70, 0x61, 0x73, 0x73, 0x77, 0x6f, 0x72, 0x64,
+		0x00,
 	}
 
 	// 2. A valid MariaDB banner (protocol-compatible)
@@ -37,46 +37,43 @@ func TestDetectMySQL(t *testing.T) {
 	// 5. A slice that starts correctly but is malformed (no null terminator)
 	malformedSlice := []byte{0x0a, 0x38, 0x2e, 0x30, 0x2e, 0x30, 0x01, 0x02, 0x03, 0x04, 0x05}
 
-	t.Run("MySQL 8", func(t *testing.T) {
+	testRunner(t, []*testCase{
-		p, c, _ := Detect(Server, mysql8Banner, 3306, 0)
+		{
-		if p == nil {
+			Name:           "MySQL server",
-			t.Fatal("expected MySQL protocol, got nil")
+			Direction:      Server,
-		}
+			Data:           mysql8Banner,
-		t.Logf("detected %s version %s confidence %g%%", p.Name, p.Version, c*100)
+			SrcPort:        3306,
-	})
+			WantProto:      ProtocolMySQL,
-
+			WantConfidence: .85,
-	t.Run("MariaDB", func(t *testing.T) {
+		},
-		p, c, _ := Detect(Server, mariaDBBanner, 3306, 0)
+		{
-		if p == nil {
+			Name:           "MariaDB server",
-			t.Fatal("expected MySQL protocol, got nil")
+			Direction:      Server,
-		}
+			Data:           mariaDBBanner,
-		t.Logf("detected %s version %s confidence %g%%", p.Name, p.Version, c*100)
+			SrcPort:        3306,
-	})
+			WantProto:      ProtocolMySQL,
-
+			WantConfidence: .85,
-	t.Run("Invalid HTTP", func(t *testing.T) {
+		},
-		_, _, err := Detect(Server, httpBanner, 1234, 80)
+		{
-		if !errors.Is(err, ErrUnknown) {
+			Name:      "Invalid HTTP",
-			t.Fatalf("expected unknown format, got error %T: %q", err, err)
+			Direction: Server,
-		} else {
+			Data:      httpBanner,
-			t.Logf("error %q, as expected", err)
+			SrcPort:   80,
-		}
+			WantError: ErrUnknown,
-	})
+		},
-
+		{
-	t.Run("Too short", func(t *testing.T) {
+			Name:      "Invalid too short",
-		_, _, err := Detect(Server, shortSlice, 3306, 1234)
+			Direction: Server,
-		if !errors.Is(err, ErrUnknown) {
+			Data:      shortSlice,
-			t.Fatalf("expected unknown format, got error %T: %q", err, err)
+			SrcPort:   3306,
-		} else {
+			WantError: ErrUnknown,
-			t.Logf("error %q, as expected", err)
+		},
-		}
+		{
-	})
+			Name:      "Invalid malformed",
-
+			Direction: Server,
-	t.Run("Malformed", func(t *testing.T) {
+			Data:      malformedSlice,
-		_, _, err := Detect(Server, malformedSlice, 3306, 1234)
+			SrcPort:   3306,
-		if !errors.Is(err, ErrUnknown) {
+			WantError: ErrUnknown,
-			t.Fatalf("expected unknown format, got error %T: %q", err, err)
+		},
-		} else {
-			t.Logf("error %q, as expected", err)
-		}
 	})
 }

protocol/detect_postgres_test.go

@@ -21,17 +21,31 @@ func TestDetectPostgreSQLClient(t *testing.T) {
 		'd', 'a', 't', 'a', 'b', 'a', 's', 'e', 0x00, 't', 'e', 's', 't', 0x00, 0x00,
 	}
 
-	t.Run("Protocol 3.0", func(t *testing.T) {
+	mysqlBanner := []byte{
-		p, c, err := Detect(Client, pgClientStartup, 0, 5432)
+		0x0a, 0x38, 0x2e, 0x30, 0x2e, 0x33, 0x32, 0x00, 0x0d, 0x00, 0x00, 0x00,
-		if err != nil {
+		0x04, 0x5a, 0x56, 0x5f, 0x3e, 0x6e, 0x76, 0x27, 0x00, 0xff, 0xff, 0xff,
-			t.Fatal(err)
+		0x02, 0x00, 0xff, 0xc7, 0x15, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-			return
+		0x00, 0x00, 0x00, 0x63, 0x61, 0x63, 0x68, 0x69, 0x6e, 0x67, 0x5f, 0x73,
-		}
+		0x68, 0x61, 0x32, 0x5f, 0x70, 0x61, 0x73, 0x73, 0x77, 0x6f, 0x72, 0x64,
-		t.Logf("detected %s version %s confidence %g%%", p.Name, p.Version, 100*c)
+		0x00,
-		if p.Name != ProtocolPostgreSQL {
-			t.Fatalf("expected postgres protocol, got %s", p.Name)
-			return
 	}
+
+	testRunner(t, []*testCase{
+		{
+			Name:           "PostgeSQL protocol 3.0",
+			Direction:      Client,
+			Data:           pgClientStartup,
+			DstPort:        5432,
+			WantProto:      ProtocolPostgreSQL,
+			WantConfidence: .85,
+		},
+		{
+			Name:      "Invalid MySQL server",
+			Direction: Server,
+			Data:      mysqlBanner,
+			SrcPort:   3306,
+			WantError: ErrUnknown,
+		},
 	})
 }
 
@@ -57,6 +71,24 @@ func TestDetectPostgreSQLServer(t *testing.T) {
 	// Invalid data (HTTP GET request)
 	httpBanner := []byte("GET / HTTP/1.1\r\nHost: example.com\r\n\r\n")
 
+	testRunner(t, []*testCase{
+		{
+			Name:           "PostgeSQL Sever AuthentcationOk",
+			Direction:      Server,
+			Data:           pgServerAuthOK,
+			DstPort:        5432,
+			WantProto:      ProtocolPostgreSQL,
+			WantConfidence: .65,
+		},
+		{
+			Name:      "Invalid HTTP request",
+			Direction: Server,
+			Data:      httpBanner,
+			SrcPort:   3306,
+			WantError: ErrUnknown,
+		},
+	})
+
 	t.Run("AuthenticationOk", func(t *testing.T) {
 		p, c, err := Detect(Server, pgServerAuthOK, 5432, 0)
 		if err != nil {

protocol/detect_ssh.go

@@ -2,17 +2,37 @@ package protocol
 
 import (
 	"bytes"
+	"strings"
 )
 
+func init() {
+	// We can't match on SSH-?.? here, because the client or server may send a banner prior
+	// to sending the SSH handshake.
+	Register(Both, "", detectSSH)
+}
+
 // The required prefix for the SSH protocol identification line.
 const (
 	ssh199Prefix = "SSH-1.99-"
 	ssh20Prefix  = "SSH-2.0-"
 )
 
-func init() {
+var (
-	Register(Both, "", detectSSH)
+	commonPort = map[int]bool{
-}
+		22:   true,
+		2200: true,
+		2222: true,
+	}
+	commonImplementations = []string{
+		"OpenSSH_",
+		"PuTTY",
+		"libssh",
+		"dropbear",
+		"Go",
+		"paramiko",
+		"Cyberduck",
+	}
+)
 
 func detectSSH(dir Direction, data []byte, srcPort, dstPort int) (proto *Protocol, confidence float64) {
 	// The data must be at least as long as the prefix itself.
@@ -20,34 +40,52 @@ func detectSSH(dir Direction, data []byte, srcPort, dstPort int) (proto *Protoco
 		return nil, 0
 	}
 
-	if dstPort == 22 || dstPort == 2200 || dstPort == 2222 {
+	if commonPort[srcPort] || commonPort[dstPort] {
-		confidence = .1
+		confidence += .1
 	}
 
 	// The protocol allows for pre-banner text, so we have to check all lines.
 	for _, line := range bytes.Split(data, []byte{'\n'}) {
 		line = bytes.TrimSuffix(line, []byte{'\r'})
+
+		// Match the most common SSH 2.0 protocol.
 		if bytes.HasPrefix(line, []byte(ssh20Prefix)) {
+			implementation := string(line[len(ssh20Prefix):])
+			for _, prefix := range commonImplementations {
+				if strings.HasPrefix(implementation, prefix) {
+					confidence += .2
+					break
+				}
+			}
 			return &Protocol{
 				Name: ProtocolSSH,
 				Version: Version{
 					Major: 2,
 					Minor: 0,
 					Patch: -1,
-					Extra: string(line[len(ssh20Prefix):]),
+					Extra: implementation,
 				},
-			}, confidence + 0.75
+			}, confidence + 0.65
 		}
+
+		// Match the (far) less common SSH 1.99 protocol.
 		if bytes.HasPrefix(line, []byte(ssh199Prefix)) {
+			implementation := string(line[len(ssh20Prefix):])
+			for _, prefix := range commonImplementations {
+				if strings.HasPrefix(implementation, prefix) {
+					confidence += .2
+					break
+				}
+			}
 			return &Protocol{
 				Name: ProtocolSSH,
 				Version: Version{
 					Major: 1,
 					Minor: 99,
 					Patch: -1,
-					Extra: string(line[len(ssh20Prefix):]),
+					Extra: implementation,
 				},
-			}, confidence + 0.75
+			}, confidence + 0.65
 		}
 	}
 

protocol/detect_ssh_test.go

@@ -1,7 +1,6 @@
 package protocol
 
 import (
-	"errors"
 	"testing"
 )
 
@@ -31,13 +30,63 @@ func TestDetectSSH(t *testing.T) {
 	// 5. A simple HTTP request
 	httpBanner := []byte("GET / HTTP/1.1\r\nHost: example.com\r\n\r\n")
 
+	testRunner(t, []*testCase{
+		{
+			Name:           "OpenSSH client",
+			Direction:      Client,
+			Data:           openSSHBanner,
+			DstPort:        22,
+			WantProto:      ProtocolSSH,
+			WantConfidence: .95,
+		},
+		{
+			Name:           "OpenSSH server",
+			Direction:      Server,
+			Data:           openSSHBanner,
+			SrcPort:        22,
+			WantProto:      ProtocolSSH,
+			WantConfidence: .95,
+		},
+		{
+			Name:           "OpenSSH server with banner",
+			Direction:      Server,
+			Data:           preBannerSSH,
+			SrcPort:        22,
+			WantProto:      ProtocolSSH,
+			WantConfidence: .95,
+		},
+		{
+			Name:           "Dropbear server",
+			Direction:      Server,
+			Data:           dropbearBanner,
+			SrcPort:        22,
+			WantProto:      ProtocolSSH,
+			WantConfidence: .95,
+		},
+		{
+			Name:      "Invalid MySQL",
+			Direction: Server,
+			Data:      mysqlBanner,
+			SrcPort:   3306,
+			WantError: ErrUnknown,
+		},
+		{
+			Name:      "Invalid HTTP",
+			Direction: Client,
+			Data:      httpBanner,
+			DstPort:   80,
+			WantError: ErrUnknown,
+		},
+	})
+
+	/*
 		t.Run("OpenSSH client", func(t *testing.T) {
-		p, _, err := Detect(Server, openSSHBanner, 0, 22)
+			p, c, err := Detect(Server, openSSHBanner, 0, 22)
 			if err != nil {
 				t.Fatal(err)
 				return
 			}
-		t.Logf("detected %s version %s", p.Name, p.Version)
+			t.Logf("detected %s version %s confidence %g%%", p.Name, p.Version, c*100)
 			if p.Name != ProtocolSSH {
 				t.Fatalf("expected ssh protocol, got %s", p.Name)
 				return
@@ -45,12 +94,12 @@ func TestDetectSSH(t *testing.T) {
 		})
 
 		t.Run("OpenSSH server", func(t *testing.T) {
-		p, _, err := Detect(Server, openSSHBanner, 0, 22)
+			p, c, err := Detect(Server, openSSHBanner, 0, 22)
 			if err != nil {
 				t.Fatal(err)
 				return
 			}
-		t.Logf("detected %s version %s", p.Name, p.Version)
+			t.Logf("detected %s version %s confidence %g%%", p.Name, p.Version, c*100)
 			if p.Name != ProtocolSSH {
 				t.Fatalf("expected ssh protocol, got %s", p.Name)
 				return
@@ -58,12 +107,12 @@ func TestDetectSSH(t *testing.T) {
 		})
 
 		t.Run("OpenSSH server with banner", func(t *testing.T) {
-		p, _, err := Detect(Server, preBannerSSH, 0, 22)
+			p, c, err := Detect(Server, preBannerSSH, 0, 22)
 			if err != nil {
 				t.Fatal(err)
 				return
 			}
-		t.Logf("detected %s version %s", p.Name, p.Version)
+			t.Logf("detected %s version %s confidence %g%%", p.Name, p.Version, c*100)
 			if p.Name != ProtocolSSH {
 				t.Fatalf("expected ssh protocol, got %s", p.Name)
 				return
@@ -71,12 +120,12 @@ func TestDetectSSH(t *testing.T) {
 		})
 
 		t.Run("Dropbear server", func(t *testing.T) {
-		p, _, err := Detect(Server, dropbearBanner, 0, 22)
+			p, c, err := Detect(Server, dropbearBanner, 0, 22)
 			if err != nil {
 				t.Fatal(err)
 				return
 			}
-		t.Logf("detected %s version %s", p.Name, p.Version)
+			t.Logf("detected %s version %s confidence %g%%", p.Name, p.Version, c*100)
 			if p.Name != ProtocolSSH {
 				t.Fatalf("expected ssh protocol, got %s", p.Name)
 				return
@@ -100,4 +149,5 @@ func TestDetectSSH(t *testing.T) {
 				t.Logf("error %q, as expected", err)
 			}
 		})
+	*/
 }

protocol/detect_tls_test.go

@@ -2,7 +2,6 @@ package protocol
 
 import (
 	"encoding/hex"
-	"errors"
 	"strings"
 	"testing"
 )
@@ -167,15 +166,74 @@ func TestDetectTLS(t *testing.T) {
 		0x00, 0x00, 0x00, 0x25, 0x00, 0x03, 0x00, 0x00,
 	}
 
+	tests := []*testCase{
+		{
+			Name:           "SSLv3",
+			Direction:      Client,
+			Data:           sslV3ClientHello,
+			DstPort:        443,
+			WantProto:      ProtocolSSL,
+			WantConfidence: .95,
+		},
+		{
+			Name:           "TLS 1.1",
+			Direction:      Client,
+			Data:           tls11ClientHello,
+			DstPort:        443,
+			WantProto:      ProtocolTLS,
+			WantConfidence: .95,
+		},
+		{
+			Name:           "TLS 1.2",
+			Direction:      Client,
+			Data:           tls12ClientHello,
+			DstPort:        443,
+			WantProto:      ProtocolTLS,
+			WantConfidence: .95,
+		},
+		{
+			Name:           "TLS 1.3",
+			Direction:      Client,
+			Data:           tls13ClientHello,
+			DstPort:        443,
+			WantProto:      ProtocolTLS,
+			WantConfidence: .95,
+		},
+		{
+			Name:      "Invalid PostgreSQL",
+			Direction: Client,
+			Data:      pgClientStartup,
+			DstPort:   5432,
+			WantError: ErrUnknown,
+		},
+	}
+
 	defer func() { Strict = false }()
 	for _, strict := range []bool{false, true} {
 		Strict = strict
 
-		name := "loose"
 		if strict {
-			name = "strict"
+			t.Run("strict", func(t *testing.T) {
+				testRunner(t, tests)
+			})
+		} else {
+			// Strict runner doesn't allow for partial packet matching:
+			t.Run("loose", func(t *testing.T) {
+				testRunner(t, append([]*testCase{
+					{
+						Name:           "TLS 1.1 partial",
+						Direction:      Client,
+						Data:           tls11ClientHelloPartial,
+						DstPort:        443,
+						WantProto:      ProtocolTLS,
+						WantConfidence: .50,
+					},
+				}, tests...))
+			})
 		}
 
+		/*
+
 			t.Run(name, func(t *testing.T) {
 
 				t.Run("SSLv3 Client Hello", func(t *testing.T) {
@@ -260,6 +318,7 @@ func TestDetectTLS(t *testing.T) {
 					}
 				})
 			})
+		*/
 	}
 }
 

protocol/detest_test.go

@@ -1,10 +1,109 @@
 package protocol
 
 import (
+	"errors"
+	"fmt"
 	"math"
+	"math/rand"
+	"strconv"
+	"strings"
 	"testing"
 )
 
+type testCase struct {
+	Name           string
+	Direction      Direction
+	Data           []byte
+	SrcPort        int
+	DstPort        int
+	WantProto      string
+	WantConfidence float64
+	WantError      error
+}
+
+func testRunner(t *testing.T, tests []*testCase) {
+	t.Helper()
+
+	for _, test := range tests {
+		t.Run(test.Name, func(t *testing.T) {
+			if test.SrcPort == 0 {
+				test.SrcPort = 1024 + rand.Intn(65535-1024)
+			}
+			if test.DstPort == 0 {
+				test.DstPort = 1024 + rand.Intn(65535-1024)
+			}
+
+			proto, confidence, err := Detect(test.Direction, test.Data, test.SrcPort, test.DstPort)
+
+			// Process error first
+			if err != nil {
+				if test.WantError == nil {
+					t.Fatalf("unexpected error: %v", err)
+				} else if !errors.Is(err, test.WantError) {
+					t.Fatalf("Detect(%s, %s, %d, %d) returned error %q, expected %q",
+						test.Direction, testBytesSample(test.Data, 8), test.SrcPort, test.DstPort,
+						err, test.WantError)
+				} else {
+					t.Logf("Detect(%s, %s, %d, %d) returned error %q as expected",
+						test.Direction, testBytesSample(test.Data, 8), test.SrcPort, test.DstPort,
+						err)
+				}
+				return
+			} else if test.WantError != nil {
+				t.Fatalf("Detect(%s, %s, %d, %d) returned protocol %q version %s, expected error %q",
+					test.Direction, testBytesSample(test.Data, 8), test.SrcPort, test.DstPort,
+					proto.Name, proto.Version, test.WantError)
+				return
+			}
+
+			// Process protocol
+			if proto == nil {
+				t.Fatalf("Detect(%s, %s, %d, %d) returned nil, expected protocol %q",
+					test.Direction, testBytesSample(test.Data, 8), test.SrcPort, test.DstPort,
+					test.WantProto)
+				return
+			}
+
+			t.Logf("Detect(%s, %s, %d, %d) returned protocol %q version %s with confidence %g%%",
+				test.Direction, testBytesSample(test.Data, 4), test.SrcPort, test.DstPort,
+				proto.Name, proto.Version, confidence*100)
+
+			if proto.Name != test.WantProto {
+				t.Errorf("Expected protocol %q", test.WantProto)
+			}
+			if !testAlmostEqual(confidence, test.WantConfidence) {
+				t.Errorf("Expected confidence %g%%", test.WantConfidence*100)
+			}
+		})
+	}
+}
+
+func testBytesSample(b []byte, n int) string {
+	if b == nil {
+		return "<nil>"
+	}
+	var (
+		hex []string
+		etc string
+	)
+	for i, l := 0, len(b); i < l && i < n; i++ {
+		if strconv.IsPrint(rune(b[i])) {
+			hex = append(hex, fmt.Sprintf("%c", b[i]))
+		} else {
+			hex = append(hex, fmt.Sprintf("\\x%02X", b[i]))
+		}
+		if i == (n-1) && l > (n-1) {
+			etc = fmt.Sprintf(" … (%d more)", l-n)
+		}
+	}
+	return fmt.Sprintf(`"%s"%s`, strings.Join(hex, ""), etc)
+}
+
+func testAlmostEqual(a, b float64) bool {
+	const e = 1e-9
+	return math.Abs(a-b) < e
+}
+
 func TestCompareFloats(t *testing.T) {
 	tests := []struct {
 		name     string