add anonymous_id and nullifier for uniqueness (#15)

* add anonymous_id and nullifier for uniqueness

* use unique index for: aid and nullifier instead of using unique field in table

config.yaml

@@ -27,6 +27,6 @@ signature_verification:
   pub_key: "04e29323ad356ab524fa5dbe3e490244e741b4d445ac7d2ee5f321556b3fda616bb9d2f2216fc27e099ab3019103cca872679e130629b2b90ea16cedb2b2136371"
 
 poseidonsmt_root_verifier:
-  rpc: rpc_url
-  contract: contract_address
+  rpc: "https://rpc.evm.mainnet.rarimo.com"
+  contract: "0xA25a197d26Cad659A8fFf7F268cA4F9e0283de03"
   request_timeout: 10s

internal/assets/migrations/005_anonymousId.sql

@@ -0,0 +1,12 @@
+-- +migrate Up
+ALTER TABLE verify_users ADD COLUMN anonymous_id TEXT DEFAULT '';
+ALTER TABLE verify_users ADD COLUMN nullifier TEXT DEFAULT '';
+
+CREATE UNIQUE INDEX verify_users_anonymous_id_unique ON verify_users(anonymous_id) WHERE anonymous_id != '';
+CREATE UNIQUE INDEX verify_users_nullifier_unique ON verify_users(nullifier) WHERE nullifier != '';
+-- +migrate Down
+ALTER TABLE verify_users DROP COLUMN anonymous_id;
+ALTER TABLE verify_users DROP COLUMN nullifier;
+
+DROP INDEX verify_users_anonymous_id_unique;
+DROP INDEX verify_users_nullifier_unique;

internal/data/pg/verify_users.go

@@ -80,6 +80,8 @@ func (q *VerifyUsersQ) Insert(VerifyUsers *data.VerifyUsers) error {
 		"sex":                VerifyUsers.Sex,
 		"sex_enable":         VerifyUsers.SexEnable,
 		"nationality_enable": VerifyUsers.NationalityEnable,
+		"anonymous_id":       VerifyUsers.AnonymousID,
+		"nullifier":          VerifyUsers.Nullifier,
 	})
 
 	if err = q.db.Exec(stmt); err != nil {
@@ -93,10 +95,12 @@ func (q *VerifyUsersQ) Update(VerifyUsers *data.VerifyUsers) error {
 	err := q.db.Exec(
 		sq.Update(verifyUsersTableName).
 			SetMap(map[string]interface{}{
-				"status":      VerifyUsers.Status,
-				"proof":       VerifyUsers.Proof,
-				"sex":         VerifyUsers.Sex,
-				"nationality": VerifyUsers.Nationality,
+				"status":       VerifyUsers.Status,
+				"proof":        VerifyUsers.Proof,
+				"sex":          VerifyUsers.Sex,
+				"nationality":  VerifyUsers.Nationality,
+				"anonymous_id": VerifyUsers.AnonymousID,
+				"nullifier":    VerifyUsers.Nullifier,
 			}).
 			Where(sq.Eq{userIdColumnName: VerifyUsers.UserID}),
 	)
@@ -144,3 +148,8 @@ func (q *VerifyUsersQ) WhereCreatedAtLt(createdAt time.Time) data.VerifyUsersQ {
 	q.del = q.del.Where(sq.Lt{createdAtColumnName: &createdAt})
 	return q
 }
+
+func (q *VerifyUsersQ) FilterByInternalAID(aid string) data.VerifyUsersQ {
+	q.sel = q.sel.Where(sq.Eq{"anonymous_id": aid})
+	return q
+}

internal/data/verify_users.go

@@ -17,6 +17,8 @@ type VerifyUsers struct {
 	Sex               string    `db:"sex"`
 	SexEnable         bool      `db:"sex_enable"`
 	NationalityEnable bool      `db:"nationality_enable"`
+	AnonymousID       string    `db:"anonymous_id"`
+	Nullifier         string    `db:"nullifier"`
 }
 
 type VerifyUsersQ interface {
@@ -32,4 +34,5 @@ type VerifyUsersQ interface {
 	WhereID(userId string) VerifyUsersQ
 	WhereHashID(userId string) VerifyUsersQ
 	WhereCreatedAtLt(createdAt time.Time) VerifyUsersQ
+	FilterByInternalAID(aid string) VerifyUsersQ
 }

internal/service/handlers/verification_callback_light.go

@@ -54,18 +54,6 @@ func VerificationSignatureCallback(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	verifiedUser, err := VerifyUsersQ(r).WhereHashID(userIDHash).Get()
-	if err != nil {
-		Log(r).WithError(err).Errorf("failed to get user with userHashID [%s]", userIDHash)
-		ape.RenderErr(w, problems.BadRequest(err)...)
-		return
-	}
-	if verifiedUser == nil {
-		Log(r).Error("user not found or eventData != userHashID")
-		ape.RenderErr(w, problems.NotFound())
-		return
-	}
-
 	userIDHashDecimal, ok := new(big.Int).SetString(pubSignals[10], 10)
 	if !ok {
 		Log(r).Error("failed to parse event data")
@@ -89,6 +77,45 @@ func VerificationSignatureCallback(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	nullifier, ok := new(big.Int).SetString(pubSignals[0], 10)
+	if !ok {
+		Log(r).Error("failed to parse nullifier")
+		ape.RenderErr(w, problems.BadRequest(err)...)
+		return
+	}
+	var nullifierBytes [32]byte
+	nullifier.FillBytes(nullifierBytes[:])
+	nullifierHex := hex.EncodeToString(nullifierBytes[:])
+
+	anonymousID, ok := new(big.Int).SetString(pubSignals[11], 10)
+	if !ok {
+		Log(r).Error("failed to parse anonymous_id")
+		ape.RenderErr(w, problems.BadRequest(err)...)
+		return
+	}
+	var anonymousIDBytes [32]byte
+	anonymousID.FillBytes(anonymousIDBytes[:])
+	anonymousIDHex := hex.EncodeToString(anonymousIDBytes[:])
+
+	byAnonymousID, err := VerifyUsersQ(r).FilterByInternalAID(anonymousIDHex).Get()
+	if err != nil {
+		Log(r).Error("Failed to get user by anonymous_id")
+		ape.RenderErr(w, problems.BadRequest(err)...)
+		return
+	}
+
+	verifiedUser, err := VerifyUsersQ(r).WhereHashID(userIDHash).Get()
+	if err != nil {
+		Log(r).WithError(err).Errorf("failed to get user with userHashID [%s]", userIDHash)
+		ape.RenderErr(w, problems.BadRequest(err)...)
+		return
+	}
+	if verifiedUser == nil {
+		Log(r).Error("user not found or eventData != userHashID")
+		ape.RenderErr(w, problems.NotFound())
+		return
+	}
+
 	if verifiedUser.Nationality == "" && pubSignals[6] != "0" {
 		verifiedUser.Nationality = nationality
 	}
@@ -97,6 +124,13 @@ func VerificationSignatureCallback(w http.ResponseWriter, r *http.Request) {
 	}
 
 	verifiedUser.Status = "verified"
+	if byAnonymousID != nil && byAnonymousID.UserIDHash != verifiedUser.UserIDHash {
+		Log(r).WithError(err).Errorf("User with anonymous_id [%s] but a different userIDHash already exists", anonymousIDHex)
+		verifiedUser.Status = "failed_verification"
+	} else {
+		verifiedUser.Nullifier = nullifierHex
+		verifiedUser.AnonymousID = anonymousIDHex
+	}
 	if eventData != userIDHash {
 		Log(r).WithError(err).Errorf("failed to verify user: EventData from pub-signals [%s] != userIdHash from db [%s]", eventData, userIDHash)
 		verifiedUser.Status = "failed_verification"