Allow backwards compatibility of Votifier votes

mcstatus-io · May 20, 2024 · 4d1a60a · 4d1a60a
1 parent f7fba5c
commit 4d1a60a
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Showing 4 changed files with 135 additions and 137 deletions.
diff --git a/go.mod b/go.mod
@@ -4,4 +4,4 @@ go 1.18
 
 require github.com/jessevdk/go-flags v1.5.0
 
-require golang.org/x/sys v0.15.0 // indirect
+require golang.org/x/sys v0.20.0 // indirect
diff --git a/go.sum b/go.sum
@@ -1,5 +1,5 @@
 github.com/jessevdk/go-flags v1.5.0 h1:1jKYvbxEjfUl0fmqTCOfonvskHHXMjBySTLW4y9LFvc=
 github.com/jessevdk/go-flags v1.5.0/go.mod h1:Fw0T6WPc1dYxT4mKEZRfG5kJhaTDP9pj1c2EWnYs/m4=
 golang.org/x/sys v0.0.0-20210320140829-1e4c9ba3b0c4/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.15.0 h1:h48lPFYpsTvQJZF4EKyI4aLHaev3CxivZmv7yZig9pc=
-golang.org/x/sys v0.15.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/sys v0.20.0 h1:Od9JTbYCk261bKm4M/mw7AklTlFYIa0bIp9BgSm1S8Y=
+golang.org/x/sys v0.20.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
diff --git a/options/vote.go b/options/vote.go
@@ -4,6 +4,7 @@ import "time"
 
 // Vote is the options used by the SendVote() function
 type Vote struct {
+	// Deprecated: This property no longer affects how the vote is sent or processed.
 	RequireVersion int
 	PublicKey      string
 	ServiceName    string

diff --git a/vote.go b/vote.go
@@ -25,11 +25,11 @@ import (
 
 var (
 	// ErrPublicKeyRequired means that the server is using Votifier 1 but the PublicKey option is missing
-	ErrPublicKeyRequired = errors.New("vote: PublicKey is a required option but the value is empty")
+	ErrPublicKeyRequired = errors.New("vote: server negotiated Votifier 1, but PublicKey option is empty")
 	// ErrInvalidPublicKey means the public key provided cannot be parsed
 	ErrInvalidPublicKey = errors.New("vote: invalid public key value")
 	// ErrPublicKeyRequired means that the server is using Votifier 2 but the Token option is missing
-	ErrTokenRequired = errors.New("vote: Token is a required option but the value is empty")
+	ErrTokenRequired = errors.New("vote: server negotiated Votifier 2, but Token option is empty")
 )
 
 type voteMessage struct {
@@ -87,8 +87,9 @@ func sendVote(host string, port uint16, opts options.Vote) error {
 	}
 
 	var (
-		challenge string
-		version   string
+		challenge    string
+		version      string
+		majorVersion string
 	)
 
 	// Handshake packet
@@ -102,159 +103,155 @@ func sendVote(host string, port uint16, opts options.Vote) error {
 
 		dataSegments := strings.Split(string(data[:len(data)-1]), " ")
 		version = dataSegments[1]
+		majorVersion = strings.Split(version, ".")[0]
 
 		if len(dataSegments) > 2 {
 			challenge = dataSegments[2]
 		}
 	}
 
-	switch strings.Split(version, ".")[0] {
-	case "1":
-		{
-			if opts.RequireVersion != 0 && opts.RequireVersion != 1 {
-				return fmt.Errorf("vote: version mismatch (server is running Votifier 1, expected to send version %d vote)", opts.RequireVersion)
-			}
+	if majorVersion != "2" && majorVersion != "1" {
+		return fmt.Errorf("vote: unknown Votifier version: %s", version)
+	}
 
-			if len(opts.PublicKey) < 1 {
-				return ErrPublicKeyRequired
-			}
+	if majorVersion == "2" && len(opts.Token) > 0 {
+		if err := sendVotifier2Vote(r, conn, host, port, challenge, opts); err != nil {
+			return err
+		}
+	} else if len(opts.PublicKey) > 0 {
+		if err := sendVotifier1Vote(conn, opts); err != nil {
+			return err
+		}
+	} else {
+		return fmt.Errorf("vote: version mismatch (server is expecting a Votifier %s packet, but options are missing to allow sending of this vote packet or any prior backwards-compatible versions)", version)
+	}
 
-			if len(opts.IPAddress) < 1 {
-				opts.IPAddress = "127.0.0.1"
-			}
+	return nil
+}
 
-			// Vote packet
-			// https://github.com/NuVotifier/NuVotifier/wiki/Technical-QA#protocol-v1-deprecated
-			{
-				block, _ := pem.Decode([]byte(fmt.Sprintf("-----BEGIN PUBLIC KEY-----\n%s\n-----END PUBLIC KEY-----", opts.PublicKey)))
+func sendVotifier1Vote(conn net.Conn, opts options.Vote) error {
+	if len(opts.IPAddress) < 1 {
+		opts.IPAddress = "127.0.0.1"
+	}
 
-				if block == nil {
-					return ErrInvalidPublicKey
-				}
+	// Vote packet
+	// https://github.com/NuVotifier/NuVotifier/wiki/Technical-QA#protocol-v1-deprecated
+	{
+		block, _ := pem.Decode([]byte(fmt.Sprintf("-----BEGIN PUBLIC KEY-----\n%s\n-----END PUBLIC KEY-----", opts.PublicKey)))
 
-				key, err := x509.ParsePKIXPublicKey(block.Bytes)
+		if block == nil {
+			return ErrInvalidPublicKey
+		}
 
-				if err != nil {
-					return err
-				}
+		key, err := x509.ParsePKIXPublicKey(block.Bytes)
 
-				publicKey, ok := key.(*rsa.PublicKey)
+		if err != nil {
+			return err
+		}
 
-				if !ok {
-					return fmt.Errorf("vote: parsed invalid key type: %T", key)
-				}
+		publicKey, ok := key.(*rsa.PublicKey)
 
-				payload := fmt.Sprintf(
-					"VOTE\n%s\n%s\n%s\n%s",
-					opts.ServiceName,
-					opts.Username,
-					opts.IPAddress,
-					opts.Timestamp.Format(time.RFC3339),
-				)
+		if !ok {
+			return fmt.Errorf("vote: parsed invalid key type: %T", key)
+		}
 
-				encryptedPayload, err := rsa.EncryptPKCS1v15(rand.Reader, publicKey, []byte(payload))
+		payload := fmt.Sprintf(
+			"VOTE\n%s\n%s\n%s\n%s",
+			opts.ServiceName,
+			opts.Username,
+			opts.IPAddress,
+			opts.Timestamp.Format(time.RFC3339),
+		)
 
-				if err != nil {
-					return err
-				}
+		encryptedPayload, err := rsa.EncryptPKCS1v15(rand.Reader, publicKey, []byte(payload))
 
-				if _, err = conn.Write(encryptedPayload); err != nil {
-					return err
-				}
-			}
+		if err != nil {
+			return err
+		}
 
-			break
+		if _, err = conn.Write(encryptedPayload); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func sendVotifier2Vote(r *bufio.Reader, conn net.Conn, host string, port uint16, challenge string, opts options.Vote) error {
+	// Vote packet
+	// https://github.com/NuVotifier/NuVotifier/wiki/Technical-QA#protocol-v2
+	{
+		buf := &bytes.Buffer{}
+
+		payload := votePayload{
+			ServiceName: opts.ServiceName,
+			Username:    opts.Username,
+			Address:     fmt.Sprintf("%s:%d", host, port),
+			Timestamp:   opts.Timestamp.UnixMilli(),
+			Challenge:   challenge,
+			UUID:        opts.UUID,
+		}
+
+		payloadData, err := json.Marshal(payload)
+
+		if err != nil {
+			return err
 		}
-	case "2":
-		{
-			if opts.RequireVersion != 0 && opts.RequireVersion != 2 {
-				return fmt.Errorf("vote: version mismatch (server is running Votifier 2, expected to send version %d vote)", opts.RequireVersion)
-			}
-
-			if len(opts.Token) < 1 {
-				return ErrTokenRequired
-			}
-
-			// Vote packet
-			// https://github.com/NuVotifier/NuVotifier/wiki/Technical-QA#protocol-v2
-			{
-				buf := &bytes.Buffer{}
-
-				payload := votePayload{
-					ServiceName: opts.ServiceName,
-					Username:    opts.Username,
-					Address:     fmt.Sprintf("%s:%d", host, port),
-					Timestamp:   opts.Timestamp.UnixMilli(),
-					Challenge:   challenge,
-					UUID:        opts.UUID,
-				}
-
-				payloadData, err := json.Marshal(payload)
-
-				if err != nil {
-					return err
-				}
-
-				hash := hmac.New(sha256.New, []byte(opts.Token))
-				hash.Write(payloadData)
-
-				message := voteMessage{
-					Payload:   string(payloadData),
-					Signature: base64.StdEncoding.EncodeToString(hash.Sum(nil)),
-				}
-
-				messageData, err := json.Marshal(message)
-
-				if err != nil {
-					return err
-				}
-
-				if err := binary.Write(buf, binary.BigEndian, uint16(0x733A)); err != nil {
-					return err
-				}
-
-				if err := binary.Write(buf, binary.BigEndian, uint16(len(messageData))); err != nil {
-					return err
-				}
-
-				if _, err := buf.Write(messageData); err != nil {
-					return err
-				}
-
-				if _, err := io.Copy(conn, buf); err != nil {
-					return err
-				}
-			}
-
-			// Response packet
-			// https://github.com/NuVotifier/NuVotifier/wiki/Technical-QA#protocol-v2
-			{
-				data, err := r.ReadBytes('\n')
-
-				if err != nil {
-					return err
-				}
-
-				response := voteResponse{}
-
-				if err = json.Unmarshal(data[:len(data)-1], &response); err != nil {
-					return err
-				}
-
-				switch response.Status {
-				case "ok":
-					break
-				case "error":
-					return fmt.Errorf("vote: server returned error: %s", response.Error)
-				default:
-					return fmt.Errorf("vote: received unexpected server response (expected=<nil>, received=%s)", response.Status)
-				}
-			}
 
+		hash := hmac.New(sha256.New, []byte(opts.Token))
+		hash.Write(payloadData)
+
+		message := voteMessage{
+			Payload:   string(payloadData),
+			Signature: base64.StdEncoding.EncodeToString(hash.Sum(nil)),
+		}
+
+		messageData, err := json.Marshal(message)
+
+		if err != nil {
+			return err
+		}
+
+		if err := binary.Write(buf, binary.BigEndian, uint16(0x733A)); err != nil {
+			return err
+		}
+
+		if err := binary.Write(buf, binary.BigEndian, uint16(len(messageData))); err != nil {
+			return err
+		}
+
+		if _, err := buf.Write(messageData); err != nil {
+			return err
+		}
+
+		if _, err := io.Copy(conn, buf); err != nil {
+			return err
+		}
+	}
+
+	// Response packet
+	// https://github.com/NuVotifier/NuVotifier/wiki/Technical-QA#protocol-v2
+	{
+		data, err := r.ReadBytes('\n')
+
+		if err != nil {
+			return err
+		}
+
+		response := voteResponse{}
+
+		if err = json.Unmarshal(data[:len(data)-1], &response); err != nil {
+			return err
+		}
+
+		switch response.Status {
+		case "ok":
 			break
+		case "error":
+			return fmt.Errorf("vote: server returned error: %s", response.Error)
+		default:
+			return fmt.Errorf("vote: received unexpected server response (expected=<nil>, received=%s)", response.Status)
 		}
-	default:
-		return fmt.Errorf("vote: unknown Votifier version: %s", version)
 	}
 
 	return nil
Original file line number	Diff line number	Diff line change
Expand Up		@@ -4,4 +4,4 @@ go 1.18

		require github.com/jessevdk/go-flags v1.5.0

		require golang.org/x/sys v0.15.0 // indirect
		require golang.org/x/sys v0.20.0 // indirect