feat: Store hashed user IP address when submitting new node

This feature added to help trace spammers. The IP address stored with
one-way hash + salt to maintain user privacy.

.env.example

@@ -16,6 +16,11 @@ IPV6_CAPABLE=false
 # #############
 APP_URL="https://xmr.ditatompel.com" # URL where user can access the web UI, don't put trailing slash
 
+# APP_SECRET is random 64-character hex string that give us 32 random bytes.
+# For now, this used for ip address salt, but may be useful for another feature
+# in the future. You can achieve this using `openssl rand -hex 32`.
+APP_SECRET=
+
 # Fiber Config
 APP_PREFORK=false
 APP_HOST="127.0.0.1"

internal/config/app.go

@@ -14,6 +14,7 @@ type App struct {
 
 	// configuration for server
 	URL    string // URL where user can access the web UI, don't put trailing slash
+	Secret string // random 64-character hex string that give us 32 random bytes
 
 	// fiber specific config
 	Prefork     bool
@@ -61,6 +62,7 @@ func LoadApp() {
 
 	// server configuration
 	app.URL = os.Getenv("APP_URL")
+	app.Secret = os.Getenv("APP_SECRET")
 
 	// fiber specific config
 	app.Host = os.Getenv("APP_HOST")

internal/database/schema.go

@@ -7,7 +7,7 @@ import (
 
 type migrateFn func(*DB) error
 
-var dbMigrate = [...]migrateFn{v1, v2, v3, v4}
+var dbMigrate = [...]migrateFn{v1, v2, v3, v4, v5}
 
 func MigrateDb(db *DB) error {
 	version := getSchemaVersion(db)
@@ -287,3 +287,18 @@ func v4(db *DB) error {
 
 	return nil
 }
+
+func v5(db *DB) error {
+	// table: tbl_node
+	slog.Debug("[DB] Adding additional columns to tbl_node")
+	_, err := db.Exec(`
+		ALTER TABLE tbl_node
+		ADD COLUMN submitter_iphash CHAR(64) NOT NULL DEFAULT ''
+		COMMENT 'hashed IP address who submitted the node'
+		AFTER date_entered;`)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}

internal/handler/response.go

@@ -66,7 +66,7 @@ func (s *fiberServer) addNodeHandler(c *fiber.Ctx) error {
 		}
 
 		moneroRepo := monero.New()
-		if err := moneroRepo.Add(f.Protocol, f.Hostname, uint(f.Port)); err != nil {
+		if err := moneroRepo.Add(c.IP(), s.secret, f.Protocol, f.Hostname, uint(f.Port)); err != nil {
 			handler := adaptor.HTTPHandler(templ.Handler(views.Alert("error", err.Error())))
 			return handler(c)
 		}
@@ -354,7 +354,7 @@ func (s *fiberServer) addNodeAPI(c *fiber.Ctx) error {
 	hostname := c.FormValue("hostname")
 
 	moneroRepo := monero.New()
-	if err := moneroRepo.Add(protocol, hostname, uint(port)); err != nil {
+	if err := moneroRepo.Add(c.IP(), s.secret, protocol, hostname, uint(port)); err != nil {
 		return c.JSON(fiber.Map{
 			"status":  "error",
 			"message": err.Error(),

internal/handler/server.go

@@ -10,6 +10,7 @@ type fiberServer struct {
 	*fiber.App
 	db     *database.DB
 	url    string
+	secret string
 }
 
 // NewServer returns a new fiber server

internal/monero/monero.go

@@ -1,7 +1,9 @@
 package monero
 
 import (
+	"crypto/sha256"
 	"database/sql"
+	"encoding/hex"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -54,6 +56,7 @@ type Node struct {
 	Latitude        float64        `json:"latitude" db:"lat"`
 	Longitude       float64        `json:"longitude" db:"lon"`
 	DateEntered     int64          `json:"date_entered,omitempty" db:"date_entered"`
+	SubmitterIPHash string         `json:"submitter_iphash,omitempty" db:"submitter_iphash"`
 	LastChecked     int64          `json:"last_checked" db:"last_checked"`
 	FailedCount     uint           `json:"failed_count,omitempty" db:"failed_count"`
 	LastCheckStatus types.JSONText `json:"last_check_statuses" db:"last_check_status"`
@@ -176,7 +179,35 @@ func (r *moneroRepo) Nodes(q QueryNodes) (Nodes, error) {
 
 	query := fmt.Sprintf(`
 		SELECT
-			*
+			id,
+			hostname,
+			ip_addr,
+			port,
+			protocol,
+			is_tor,
+			is_i2p,
+			is_available,
+			nettype,
+			height,
+			adjusted_time,
+			database_size,
+			difficulty,
+			version,
+			uptime,
+			estimate_fee,
+			asn,
+			asn_name,
+			country,
+			country_name,
+			city,
+			lat,
+			lon,
+			date_entered,
+			last_checked,
+			last_check_status,
+			cors_capable,
+			ipv6_only,
+			ip_addresses
 		FROM
 			tbl_node
 		%s
@@ -190,7 +221,7 @@ func (r *moneroRepo) Nodes(q QueryNodes) (Nodes, error) {
 	return nodes, err
 }
 
-func (r *moneroRepo) Add(protocol string, hostname string, port uint) error {
+func (r *moneroRepo) Add(submitterIP, salt, protocol, hostname string, port uint) error {
 	if protocol != "http" && protocol != "https" {
 		return errors.New("Invalid protocol, must one of or HTTP/HTTPS")
 	}
@@ -270,6 +301,7 @@ func (r *moneroRepo) Add(protocol string, hostname string, port uint) error {
 			lat,
 			lon,
 			date_entered,
+			submitter_iphash,
 			last_checked,
 			last_check_status,
 			ip_addresses,
@@ -288,6 +320,7 @@ func (r *moneroRepo) Add(protocol string, hostname string, port uint) error {
 			?,
 			?,
 			?,
+			?,
 			?
 		)`,
 		protocol,
@@ -300,6 +333,7 @@ func (r *moneroRepo) Add(protocol string, hostname string, port uint) error {
 		0,
 		0,
 		time.Now().Unix(),
+		hashIPWithSalt(submitterIP, salt),
 		0,
 		string(statusDb),
 		ips,
@@ -397,6 +431,14 @@ func (r *moneroRepo) Countries() ([]Countries, error) {
 	return c, err
 }
 
+// hashIPWithSalt hashes IP address with salt designed for checksumming, but
+// still maintain user privacy, this is NOT cryptographic security.
+func hashIPWithSalt(ip, salt string) string {
+	hasher := sha256.New()
+	hasher.Write([]byte(salt + ip)) // Combine salt and IP
+	return hex.EncodeToString(hasher.Sum(nil))
+}
+
 // ParseNodeStatuses parses JSONText into [5]int
 // Used this to parse last_check_status for templ engine
 func ParseNodeStatuses(statuses types.JSONText) [5]int {