initial commit on Federted servers

internal/auth/bcrypt.go

@@ -0,0 +1,19 @@
+package auth
+
+import (
+	"golang.org/x/crypto/bcrypt"
+)
+
+// bcryptHash hashes a password with cost 12 (porting guide 3.1).
+func bcryptHashImpl(password string) (string, error) {
+	h, err := bcrypt.GenerateFromPassword([]byte(password), bcryptCost)
+	if err != nil {
+		return "", err
+	}
+	return string(h), nil
+}
+
+// bcryptCheck compares a password against a bcrypt hash.
+func bcryptCheckImpl(password, hash string) bool {
+	return bcrypt.CompareHashAndPassword([]byte(hash), []byte(password)) == nil
+}