From 163fa188454f31e5f0216d7d39eaf6b2a55aff8c Mon Sep 17 00:00:00 2001
From: Mathis Maquenne <124215603+mathismqn@users.noreply.github.com>
Date: Wed, 29 Jul 2026 11:20:49 +0200
Subject: [PATCH] feat: add AES-ECB crypto helpers for email/password login

---
 internal/crypto/ecb.go | 42 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)
 create mode 100644 internal/crypto/ecb.go

diff --git a/internal/crypto/ecb.go b/internal/crypto/ecb.go
new file mode 100644
index 0000000..14c994c
--- /dev/null
+++ b/internal/crypto/ecb.go
@@ -0,0 +1,42 @@
+package crypto
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"fmt"
+)
+
+func ZeroPad(data []byte) []byte {
+	bs := aes.BlockSize
+	padded := make([]byte, len(data)+(bs-len(data)%bs)%bs)
+	copy(padded, data)
+
+	return padded
+}
+
+func EncryptECB(key, data []byte) ([]byte, error) {
+	return ecbTransform(key, data, (cipher.Block).Encrypt)
+}
+
+func DecryptECB(key, data []byte) ([]byte, error) {
+	return ecbTransform(key, data, (cipher.Block).Decrypt)
+}
+
+func ecbTransform(key, data []byte, op func(cipher.Block, []byte, []byte)) ([]byte, error) {
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+
+	bs := block.BlockSize()
+	if len(data)%bs != 0 {
+		return nil, fmt.Errorf("data length %d is not a multiple of the AES block size", len(data))
+	}
+
+	out := make([]byte, len(data))
+	for i := 0; i < len(data); i += bs {
+		op(block, out[i:i+bs], data[i:i+bs])
+	}
+
+	return out, nil
+}