Reputation: 769
I want to create a user authentication system using Go and I am stuck with logging into an account. I use bcrypt to hash passwords than I save it to the database (MySQL). The problem shows when I want to compare it with an inserted password. I have this error: hashedSecret too short to be a bcrypted password
. I don't know what I'm doing wrong. Here is my code:
models.go
type User struct {
ID string `json:"id"`
Username string `json:"username"`
Password string `json:"password"`
IsAdmin bool `json:"is_admin"`
}
user-routes.go (login func)
err := db.QueryRow("SELECT Password FROM Users WHERE Username = ?", user.Username).Scan(&storedPass)
if err != nil {
log.Fatal(err)
}
// hashed password
fmt.Println(storedPass, []byte(storedPass))
err = bcrypt.CompareHashAndPassword([]byte(storedPass), []byte(user.Password))
if err != nil {
// Here is error
fmt.Println(err.Error())
}
user-routes.go (register func)
stmt, err := db.Prepare(`INSERT INTO Users(Username, Password, IsAdmin) VALUES (?, ?, 0)`)
if err != nil {
log.Fatal(err)
}
hash, _ := bcrypt.GenerateFromPassword([]byte(user.Password), 10)
res, err := stmt.Exec(user.Username, string(hash))
It looks like the error is when I compare hashed password with an inserted password. Also, I save a password to a database without any errors.
+----+----------+----------------------------------------------------+---------+
| ID | Username | Password | IsAdmin |
+----+----------+----------------------------------------------------+---------+
| 38 | test2 | $2a$10$5WwRQahtjgmaeIKRGXGZNOLVAv5EXUidRwbnZeryq9e | 0 |
+----+----------+----------------------------------------------------+---------+
Upvotes: 4
Views: 11137
Reputation: 14928
bcrypt
produces hashes of 59-60 bytes (see this answer for details). In order to store the hash as varchar
, you need to ensure its size is sufficient. According to your comment, you use varchar(50)
, which is not enough, and that's the reason that changing its size fixed your problem.
Upvotes: 9