add login and logout endpoints

Signed-off-by: Tobias Erbshäußer <tobias@tesoft.dev>

backend/db.go

@@ -1,9 +1,12 @@
 package main
 
 import (
+	"crypto/rand"
+	"crypto/sha512"
 	"database/sql"
 	"errors"
 	"log"
+	"slices"
 	"strconv"
 	"time"
 
@@ -14,7 +17,7 @@ type Database struct {
 	db *sql.DB
 }
 
-func NewDatabase(path string) (*Database, error) {
+func NewDatabase(path string, rootPassword string) (*Database, error) {
 	log.Println("Opening database '" + path + "'")
 
 	db, err := sql.Open("sqlite3", path)
@@ -22,7 +25,7 @@ func NewDatabase(path string) (*Database, error) {
 		return nil, err
 	}
 
-	err = migrate(db)
+	err = migrate(db, rootPassword)
 	if err != nil {
 		_ = db.Close()
 		return nil, err
@@ -38,6 +41,18 @@ func (db *Database) Close() {
 	}
 }
 
+func (db *Database) ValidateRootPassword(password string) (bool, error) {
+	var salt []byte
+	var rootPasswordHash []byte
+	err := db.db.QueryRow("SELECT salt, root_password FROM schema_info").Scan(&salt, &rootPasswordHash)
+	if err != nil {
+		return false, err
+	}
+
+	passwordHash := sha512.Sum512(append(salt, []byte(password)...))
+	return slices.Compare(passwordHash[:], rootPasswordHash) == 0, nil
+}
+
 func (db *Database) CreateBlogArticle() (int64, func(*Article) error, error) {
 	tx, err := db.db.Begin()
 	if err != nil {
@@ -188,10 +203,10 @@ func (db *Database) GetBlogArticles(showAll bool, offset int, limit int) ([]Arti
 	return articles, nil
 }
 
-func migrate(db *sql.DB) error {
+func migrate(db *sql.DB, rootPassword string) error {
 	tx, err := db.Begin()
 	if err != nil {
-		log.Fatal(err)
+		return err
 	}
 
 	log.Println("Checking database schema version")
@@ -204,7 +219,7 @@ func migrate(db *sql.DB) error {
 	if curVersion == -1 {
 		log.Println("Database is empty")
 
-		err = createV1Tables(tx)
+		err = createV1Tables(tx, rootPassword)
 		if err != nil {
 			_ = tx.Rollback()
 			return err
@@ -213,27 +228,41 @@ func migrate(db *sql.DB) error {
 		log.Println("Database schema version is", curVersion)
 
 		if curVersion != 1 {
-			log.Fatalln("Unsupported database schema version")
+			return errors.New("unsupported database schema version")
 		}
 	}
 
 	return tx.Commit()
 }
 
-func createV1Tables(tx *sql.Tx) error {
+func createV1Tables(tx *sql.Tx, rootPassword string) error {
 	log.Println("Creating tables for schema version 1")
 
+	salt := make([]byte, 32)
+	_, _ = rand.Read(salt)
+
+	if rootPassword == "" {
+		return errors.New("root password is required")
+	}
+	rootPasswordHash := sha512.Sum512(append(salt, []byte(rootPassword)...))
+
 	_, err := tx.Exec(`
 		CREATE TABLE schema_info(
 		    id INTEGER PRIMARY KEY CHECK(id = 0),
-		    version INTEGER NOT NULL
+		    version INTEGER NOT NULL,
+		    salt BLOB NOT NULL,
+		    root_password BLOB NOT NULL
 		);
 		INSERT INTO schema_info(
 			id,
-			version
+			version,
+			salt,
+			root_password
 		) VALUES (
 		 	0,
-		  	1
+		  	1,
+		  	?,
+		  	?
 		);
 
 		CREATE TABLE blog_tag(
@@ -260,7 +289,7 @@ func createV1Tables(tx *sql.Tx) error {
 		    PRIMARY KEY(id, articleId),
 		    FOREIGN KEY(articleId) REFERENCES blog_article(id)
 		);
-	`)
+	`, salt, rootPasswordHash[:])
 	if err != nil {
 		return err
 	}