initial commit

1 files changed, 46 insertions, 0 deletions

diff --git a/src/server/helper/crypto.go b/src/server/helper/crypto.go
new file mode 100644
index 0000000..d676fba
--- /dev/null
+++ b/src/server/helper/crypto.go
@@ -0,0 +1,46 @@
+package helper
+
+import (
+	"crypto/rand"
+	"encoding/base64"
+
+	"golang.org/x/crypto/scrypt"
+)
+
+// Recommended https://pkg.go.dev/golang.org/x/crypto/scrypt
+const SCRYPT_N = 32768
+const SCRYPT_R = 8
+const SCRYPT_P = 1
+const SCRYPT_L = 64
+
+const SALT_LENGTH = SCRYPT_L
+
+func getEncoding() *base64.Encoding {
+	return base64.StdEncoding.WithPadding(base64.NoPadding)
+}
+
+// Generates truly random bytes.
+func generateRandomBytes(len int) ([]byte, error) {
+	salt := make([]byte, len)
+	_, err := rand.Read(salt)
+	if err != nil {
+		return nil, err
+	}
+	return salt, nil
+}
+
+func GenerateSalt() (string, error) {
+	salt, err := generateRandomBytes(SALT_LENGTH)
+	if err != nil {
+		return "", err
+	}
+	return getEncoding().EncodeToString(salt), nil
+}
+
+func GenerateHash(password string, salt string) (string, error) {
+	hash, err := scrypt.Key([]byte(password), []byte(salt), SCRYPT_N, SCRYPT_R, SCRYPT_P, SCRYPT_L)
+	if err != nil {
+		return "", err
+	}
+	return getEncoding().EncodeToString(hash), nil
+}