WIP: Add event handling with Schnorr signature verification

events/events.go

@@ -2,59 +2,146 @@ package events
 
 import (
 	"context"
+	"crypto/sha256"
+	"encoding/hex"
+	"encoding/json"
 	"fmt"
 
+	"github.com/btcsuite/btcd/btcec/v2"
+	"github.com/btcsuite/btcd/btcec/v2/schnorr"
 	"go.mongodb.org/mongo-driver/bson"
 	"go.mongodb.org/mongo-driver/mongo"
 	"go.mongodb.org/mongo-driver/mongo/options"
+	"golang.org/x/net/websocket"
 )
 
 type Event struct {
-	ID        string   `json:"id"`
-	PubKey    string   `json:"pubkey"`
-	CreatedAt int64    `json:"created_at"`
-	Kind      int      `json:"kind"`
-	Tags      []string `json:"tags"`
-	Content   string   `json:"content"`
-	Sig       string   `json:"sig"`
+	ID        string     `json:"id"`
+	PubKey    string     `json:"pubkey"`
+	CreatedAt int64      `json:"created_at"`
+	Kind      int        `json:"kind"`
+	Tags      [][]string `json:"tags"`
+	Content   string     `json:"content"`
+	Sig       string     `json:"sig"`
 }
 
-var eventKind0Collection *mongo.Collection
-var eventKind1Collection *mongo.Collection
+var collections = make(map[int]*mongo.Collection)
 
-func InitCollections(client *mongo.Client, eventKind0, eventKind1 string) {
-	eventKind0Collection = client.Database("grain").Collection(eventKind0)
-	eventKind1Collection = client.Database("grain").Collection(eventKind1)
+func InitCollections(client *mongo.Client, kinds ...int) {
+	for _, kind := range kinds {
+		collectionName := fmt.Sprintf("event-kind%d", kind)
+		collections[kind] = client.Database("grain").Collection(collectionName)
+		indexModel := mongo.IndexModel{
+			Keys:    bson.D{{Key: "id", Value: 1}},
+			Options: options.Index().SetUnique(true),
+		}
+		_, err := collections[kind].Indexes().CreateOne(context.TODO(), indexModel)
+		if err != nil {
+			fmt.Printf("Failed to create index on %s: %v\n", collectionName, err)
+		}
+	}
+}
 
+func GetCollection(kind int, client *mongo.Client) *mongo.Collection {
+	if collection, exists := collections[kind]; exists {
+		return collection
+	}
+	collectionName := fmt.Sprintf("event-kind%d", kind)
+	collection := client.Database("grain").Collection(collectionName)
+	collections[kind] = collection
 	indexModel := mongo.IndexModel{
 		Keys:    bson.D{{Key: "id", Value: 1}},
 		Options: options.Index().SetUnique(true),
 	}
-	_, err := eventKind0Collection.Indexes().CreateOne(context.TODO(), indexModel)
+	_, err := collection.Indexes().CreateOne(context.TODO(), indexModel)
 	if err != nil {
-		fmt.Println("Failed to create index on event-kind0: ", err)
-	}
-	_, err = eventKind1Collection.Indexes().CreateOne(context.TODO(), indexModel)
-	if err != nil {
-		fmt.Println("Failed to create index on event-kind1: ", err)
+		fmt.Printf("Failed to create index on %s: %v\n", collectionName, err)
 	}
+	return collection
 }
 
-func HandleEvent(ctx context.Context, evt Event) error {
+func HandleEvent(ctx context.Context, evt Event, client *mongo.Client, ws *websocket.Conn) {
+	if !ValidateEvent(evt) {
+		sendOKResponse(ws, evt.ID, false, "invalid: signature verification failed")
+		return
+	}
+
+	collection := GetCollection(evt.Kind, client)
+
+	var err error
 	switch evt.Kind {
 	case 0:
-		return HandleEventKind0(ctx, evt, eventKind0Collection)
+		err = HandleEventKind0(ctx, evt, collection)
 	case 1:
-		return HandleEventKind1(ctx, evt, eventKind1Collection)
+		err = HandleEventKind1(ctx, evt, collection)
 	default:
-		fmt.Println("Unknown event kind:", evt.Kind)
-		return fmt.Errorf("unknown event kind: %d", evt.Kind)
+		err = HandleDefaultEvent(ctx, evt, collection)
 	}
+
+	if err != nil {
+		sendOKResponse(ws, evt.ID, false, fmt.Sprintf("error: %v", err))
+		return
+	}
+
+	sendOKResponse(ws, evt.ID, true, "")
 }
 
-func GetCollections() map[string]*mongo.Collection {
-	return map[string]*mongo.Collection{
-		"eventKind0": eventKind0Collection,
-		"eventKind1": eventKind1Collection,
-	}
+func sendOKResponse(ws *websocket.Conn, eventID string, status bool, message string) {
+	response := []interface{}{"OK", eventID, status, message}
+	responseBytes, _ := json.Marshal(response)
+	websocket.Message.Send(ws, string(responseBytes))
+}
+
+func ValidateEvent(evt Event) bool {
+	serializedEvent := SerializeEvent(evt)
+	hash := sha256.Sum256(serializedEvent)
+	eventID := hex.EncodeToString(hash[:])
+	if eventID != evt.ID {
+		return false
+	}
+
+	sigBytes, err := hex.DecodeString(evt.Sig)
+	if err != nil {
+		return false
+	}
+
+	sig, err := schnorr.ParseSignature(sigBytes)
+	if err != nil {
+		return false
+	}
+
+	pubKeyBytes, err := hex.DecodeString(evt.PubKey)
+	if err != nil {
+		return false
+	}
+
+	pubKey, err := btcec.ParsePubKey(pubKeyBytes)
+	if err != nil {
+		return false
+	}
+
+	return sig.Verify(hash[:], pubKey)
+}
+
+func SerializeEvent(evt Event) []byte {
+	eventData := []interface{}{
+		0,
+		evt.PubKey,
+		evt.CreatedAt,
+		evt.Kind,
+		evt.Tags,
+		evt.Content,
+	}
+	serializedEvent, _ := json.Marshal(eventData)
+	return serializedEvent
+}
+
+func HandleDefaultEvent(ctx context.Context, evt Event, collection *mongo.Collection) error {
+	_, err := collection.InsertOne(ctx, evt)
+	if err != nil {
+		return fmt.Errorf("Error inserting default event into MongoDB: %v", err)
+	}
+
+	fmt.Println("Inserted default event into MongoDB:", evt.ID)
+	return nil
 }

events/kind0.go

@@ -10,11 +10,6 @@ import (
 )
 
 func HandleEventKind0(ctx context.Context, evt Event, collection *mongo.Collection) error {
-	// Perform specific validation for event kind 0
-	if !isValidEventKind0(evt) {
-		return fmt.Errorf("validation failed for event kind 0: %s", evt.ID)
-	}
-
 	// Replace the existing event if it has the same pubkey
 	filter := bson.M{"pubkey": evt.PubKey}
 	update := bson.M{
@@ -28,21 +23,12 @@ func HandleEventKind0(ctx context.Context, evt Event, collection *mongo.Collecti
 		},
 	}
 
-	options := options.Update().SetUpsert(true) // Insert if not found
-	_, err := collection.UpdateOne(ctx, filter, update, options)
+	opts := options.Update().SetUpsert(true) // Insert if not found
+	_, err := collection.UpdateOne(ctx, filter, update, opts)
 	if err != nil {
-		fmt.Println("Error updating/inserting event kind 0 into MongoDB:", err)
-		return err
+		return fmt.Errorf("Error updating/inserting event kind 0 into MongoDB: %v", err)
 	}
 
 	fmt.Println("Upserted event kind 0 into MongoDB:", evt.ID)
 	return nil
 }
-
-func isValidEventKind0(evt Event) bool {
-	// Placeholder for actual validation logic
-	if evt.Content == "" {
-		return false
-	}
-	return true
-}

events/kind1.go

@@ -8,26 +8,12 @@ import (
 )
 
 func HandleEventKind1(ctx context.Context, evt Event, collection *mongo.Collection) error {
-	// Perform specific validation for event kind 1
-	if !isValidEventKind1(evt) {
-		return fmt.Errorf("validation failed for event kind 1: %s", evt.ID)
-	}
-
 	// Insert event into MongoDB
 	_, err := collection.InsertOne(ctx, evt)
 	if err != nil {
-		fmt.Println("Error inserting event into MongoDB:", err)
-		return err
+		return fmt.Errorf("Error inserting event into MongoDB: %v", err)
 	}
 
 	fmt.Println("Inserted event kind 1 into MongoDB:", evt.ID)
 	return nil
 }
-
-func isValidEventKind1(evt Event) bool {
-	// Placeholder for actual validation logic
-	if evt.Content == "" {
-		return false
-	}
-	return true
-}

go.mod

@@ -8,6 +8,10 @@ require (
 )
 
 require (
+	github.com/btcsuite/btcd/btcec/v2 v2.3.4 // indirect
+	github.com/btcsuite/btcd/chaincfg/chainhash v1.0.1 // indirect
+	github.com/decred/dcrd/crypto/blake256 v1.0.0 // indirect
+	github.com/decred/dcrd/dcrec/secp256k1/v4 v4.0.1 // indirect
 	github.com/golang/snappy v0.0.4 // indirect
 	github.com/klauspost/compress v1.13.6 // indirect
 	github.com/montanaflynn/stats v0.7.1 // indirect

go.sum

@@ -1,5 +1,13 @@
+github.com/btcsuite/btcd/btcec/v2 v2.3.4 h1:3EJjcN70HCu/mwqlUsGK8GcNVyLVxFDlWurTXGPFfiQ=
+github.com/btcsuite/btcd/btcec/v2 v2.3.4/go.mod h1:zYzJ8etWJQIv1Ogk7OzpWjowwOdXY1W/17j2MW85J04=
+github.com/btcsuite/btcd/chaincfg/chainhash v1.0.1 h1:q0rUy8C/TYNBQS1+CGKw68tLOFYSNEs0TFnxxnS9+4U=
+github.com/btcsuite/btcd/chaincfg/chainhash v1.0.1/go.mod h1:7SFka0XMvUgj3hfZtydOrQY2mwhPclbT2snogU7SQQc=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/decred/dcrd/crypto/blake256 v1.0.0 h1:/8DMNYp9SGi5f0w7uCm6d6M4OU2rGFK09Y2A4Xv7EE0=
+github.com/decred/dcrd/crypto/blake256 v1.0.0/go.mod h1:sQl2p6Y26YV+ZOcSTP6thNdn47hh8kt6rqSlvmrXFAc=
+github.com/decred/dcrd/dcrec/secp256k1/v4 v4.0.1 h1:YLtO71vCjJRCBcrPMtQ9nqBsqpA1m5sE92cU+pd5Mcc=
+github.com/decred/dcrd/dcrec/secp256k1/v4 v4.0.1/go.mod h1:hyedUtir6IdtD/7lIxGeCxkaw7y45JueMRL4DIyJDKs=
 github.com/golang/snappy v0.0.4 h1:yAGX7huGHXlcLOEtBnF4w7FQwA26wojNCwOYAEhLjQM=
 github.com/golang/snappy v0.0.4/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
 github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=

main.go

@@ -28,7 +28,7 @@ func main() {
 	defer db.DisconnectDB(client)
 
 	// Initialize collections
-	events.InitCollections(client, config.Collections.EventKind0, config.Collections.EventKind1)
+	events.InitCollections(client, 0, 1) // Initialize known kinds
 
 	server.SetClient(client)
 

server/server.go

@@ -7,6 +7,8 @@ import (
 	"grain/events"
 	"time"
 
+	"grain/utils"
+
 	"go.mongodb.org/mongo-driver/mongo"
 	"golang.org/x/net/websocket"
 )
@@ -101,11 +103,7 @@ func handleEvent(ws *websocket.Conn, message []interface{}) {
 		return
 	}
 
-	err = events.HandleEvent(context.TODO(), evt)
-	if err != nil {
-		fmt.Println("Error handling event:", err)
-		return
-	}
+	events.HandleEvent(context.TODO(), evt, client, ws)
 
 	fmt.Println("Event processed:", evt.ID)
 }
@@ -131,13 +129,13 @@ func handleReq(ws *websocket.Conn, message []interface{}) {
 		}
 
 		var f Filter
-		f.IDs = toStringArray(filterData["ids"])
-		f.Authors = toStringArray(filterData["authors"])
-		f.Kinds = toIntArray(filterData["kinds"])
-		f.Tags = toTagsMap(filterData["tags"])
-		f.Since = toTime(filterData["since"])
-		f.Until = toTime(filterData["until"])
-		f.Limit = toInt(filterData["limit"])
+		f.IDs = utils.ToStringArray(filterData["ids"])
+		f.Authors = utils.ToStringArray(filterData["authors"])
+		f.Kinds = utils.ToIntArray(filterData["kinds"])
+		f.Tags = utils.ToTagsMap(filterData["tags"])
+		f.Since = utils.ToTime(filterData["since"])
+		f.Until = utils.ToTime(filterData["until"])
+		f.Limit = utils.ToInt(filterData["limit"])
 
 		filters[i] = f
 	}
@@ -194,93 +192,4 @@ func handleClose(ws *websocket.Conn, message []interface{}) {
 		fmt.Println("Error sending CLOSE message:", err)
 		return
 	}
-}
-
-func toStringArray(i interface{}) []string {
-	if i == nil {
-		return nil
-	}
-	arr, ok := i.([]interface{})
-	if !ok {
-		return nil
-	}
-	var result []string
-	for _, v := range arr {
-		str, ok := v.(string)
-		if ok {
-			result = append(result, str)
-		}
-	}
-	return result
-}
-
-func toIntArray(i interface{}) []int {
-	if i == nil {
-		return nil
-	}
-	arr, ok := i.([]interface{})
-	if !ok {
-		return nil
-	}
-	var result []int
-	for _, v := range arr {
-		num, ok := v.(float64)
-		if ok {
-			result = append(result, int(num))
-		}
-	}
-	return result
-}
-
-func toTagsMap(i interface{}) map[string][]string {
-	if i == nil {
-		return nil
-	}
-	tags, ok := i.(map[string]interface{})
-	if !ok {
-		return nil
-	}
-	result := make(map[string][]string)
-	for k, v := range tags {
-		result[k] = toStringArray(v)
-	}
-	return result
-}
-
-func toInt64(i interface{}) *int64 {
-	if i == nil {
-		return nil
-	}
-	num, ok := i.(float64)
-	if !ok {
-		return nil
-	}
-	val := int64(num)
-	return &val
-}
-
-func toInt(i interface{}) *int {
-	if i == nil {
-		return nil
-	}
-	num, ok := i.(float64)
-	if !ok {
-		return nil
-	}
-	val := int(num)
-	return &val
-}
-
-func toTime(data interface{}) *time.Time {
-	if data == nil {
-		return nil
-	}
-	// Ensure data is a float64 which MongoDB uses for numbers
-	timestamp, ok := data.(float64)
-	if !ok {
-		fmt.Println("Invalid timestamp format")
-		return nil
-	}
-	t := time.Unix(int64(timestamp), 0).UTC()
-	return &t
-}
+}

utils/decode.go

@@ -0,0 +1,95 @@
+package utils
+
+import (
+	"fmt"
+	"time"
+)
+
+func ToStringArray(i interface{}) []string {
+	if i == nil {
+		return nil
+	}
+	arr, ok := i.([]interface{})
+	if !ok {
+		return nil
+	}
+	var result []string
+	for _, v := range arr {
+		str, ok := v.(string)
+		if ok {
+			result = append(result, str)
+		}
+	}
+	return result
+}
+
+func ToIntArray(i interface{}) []int {
+	if i == nil {
+		return nil
+	}
+	arr, ok := i.([]interface{})
+	if !ok {
+		return nil
+	}
+	var result []int
+	for _, v := range arr {
+		num, ok := v.(float64)
+		if ok {
+			result = append(result, int(num))
+		}
+	}
+	return result
+}
+
+func ToTagsMap(i interface{}) map[string][]string {
+	if i == nil {
+		return nil
+	}
+	tags, ok := i.(map[string]interface{})
+	if !ok {
+		return nil
+	}
+	result := make(map[string][]string)
+	for k, v := range tags {
+		result[k] = ToStringArray(v)
+	}
+	return result
+}
+
+func ToInt64(i interface{}) *int64 {
+	if i == nil {
+		return nil
+	}
+	num, ok := i.(float64)
+	if !ok {
+		return nil
+	}
+	val := int64(num)
+	return &val
+}
+
+func ToInt(i interface{}) *int {
+	if i == nil {
+		return nil
+	}
+	num, ok := i.(float64)
+	if !ok {
+		return nil
+	}
+	val := int(num)
+	return &val
+}
+
+func ToTime(data interface{}) *time.Time {
+	if data == nil {
+		return nil
+	}
+	// Ensure data is a float64 which MongoDB uses for numbers
+	timestamp, ok := data.(float64)
+	if !ok {
+		fmt.Println("Invalid timestamp format")
+		return nil
+	}
+	t := time.Unix(int64(timestamp), 0).UTC()
+	return &t
+}