core/crypto/_aes: 64-bit portable implementation

core/crypto/_aes/ct64/api.odin

@@ -0,0 +1,96 @@
+package aes_ct64
+
+import "base:intrinsics"
+import "core:mem"
+
+STRIDE :: 4
+
+// Context is a keyed AES (ECB) instance.
+Context :: struct {
+	_sk_exp:         [120]u64,
+	_num_rounds:     int,
+	_is_initialized: bool,
+}
+
+// init initializes a context for AES with the provided key.
+init :: proc(ctx: ^Context, key: []byte) {
+	skey: [30]u64 = ---
+
+	ctx._num_rounds = keysched(skey[:], key)
+	skey_expand(ctx._sk_exp[:], skey[:], ctx._num_rounds)
+	ctx._is_initialized = true
+}
+
+// encrypt_block sets `dst` to `AES-ECB-Encrypt(src)`.
+encrypt_block :: proc(ctx: ^Context, dst, src: []byte) {
+	assert(ctx._is_initialized)
+
+	q: [8]u64
+	load_blockx1(&q, src)
+	_encrypt(&q, ctx._sk_exp[:], ctx._num_rounds)
+	store_blockx1(dst, &q)
+}
+
+// encrypt_block sets `dst` to `AES-ECB-Decrypt(src)`.
+decrypt_block :: proc(ctx: ^Context, dst, src: []byte) {
+	assert(ctx._is_initialized)
+
+	q: [8]u64
+	load_blockx1(&q, src)
+	_decrypt(&q, ctx._sk_exp[:], ctx._num_rounds)
+	store_blockx1(dst, &q)
+}
+
+// encrypt_blocks sets `dst` to `AES-ECB-Encrypt(src[0], .. src[n])`.
+encrypt_blocks :: proc(ctx: ^Context, dst, src: [][]byte) {
+	assert(ctx._is_initialized)
+
+	q: [8]u64 = ---
+	src, dst := src, dst
+
+	n := len(src)
+	for n > 4 {
+		load_blocks(&q, src[0:4])
+		_encrypt(&q, ctx._sk_exp[:], ctx._num_rounds)
+		store_blocks(dst[0:4], &q)
+
+		src = src[4:]
+		dst = dst[4:]
+		n -= 4
+	}
+	if n > 0 {
+		load_blocks(&q, src)
+		_encrypt(&q, ctx._sk_exp[:], ctx._num_rounds)
+		store_blocks(dst, &q)
+	}
+}
+
+// decrypt_blocks sets dst to `AES-ECB-Decrypt(src[0], .. src[n])`.
+decrypt_blocks :: proc(ctx: ^Context, dst, src: [][]byte) {
+	assert(ctx._is_initialized)
+
+	q: [8]u64 = ---
+	src, dst := src, dst
+
+	n := len(src)
+	for n > 4 {
+		load_blocks(&q, src[0:4])
+		_decrypt(&q, ctx._sk_exp[:], ctx._num_rounds)
+		store_blocks(dst[0:4], &q)
+
+		src = src[4:]
+		dst = dst[4:]
+		n -= 4
+	}
+	if n > 0 {
+		load_blocks(&q, src)
+		_decrypt(&q, ctx._sk_exp[:], ctx._num_rounds)
+		store_blocks(dst, &q)
+	}
+}
+
+// reset sanitizes the Context.  The Context must be re-initialized to
+// be used again.
+reset :: proc(ctx: ^Context) {
+	mem.zero_explicit(ctx, size_of(ctx))
+}