feat: hashing user passwords

solves problems #2944, #2783

util/crypto/crypto.go

@@ -0,0 +1,15 @@
+package crypto
+
+import (
+	"golang.org/x/crypto/bcrypt"
+)
+
+func HashPasswordAsBcrypt(password string) (string, error) {
+	hash, err := bcrypt.GenerateFromPassword([]byte(password), bcrypt.DefaultCost)
+	return string(hash), err
+}
+
+func CheckPasswordHash(hash, password string) bool {
+	err := bcrypt.CompareHashAndPassword([]byte(hash), []byte(password))
+	return err == nil
+}