1 files changed, 104 insertions, 0 deletions
diff --git a/aes/src/block.c b/aes/src/block.c
new file mode 100644
index 0000000..552c445
--- /dev/null
+++ b/aes/src/block.c
@@ -0,0 +1,104 @@
+/*
+ * Copyright (c) 2026 Egor Tensin <Egor.Tensin@gmail.com>
+ * This file is part of the "AES tools" project.
+ * For details, see https://github.com/egor-tensin/aes-tools.
+ * Distributed under the MIT License.
+ */
+
+#include <aes/all.h>
+
+#include <assert.h>
+#include <emmintrin.h>
+#include <stdio.h>
+#include <string.h>
+#include <tmmintrin.h>
+
+static AES_Block reverse_byte_order(AES_Block block) {
+    return _mm_shuffle_epi8(block, aes_make_block(0x00010203, 0x04050607, 0x08090a0b, 0x0c0d0e0f));
+}
+
+AES_Block aes_inc_block(AES_Block x) {
+    x = reverse_byte_order(x);
+    x = _mm_add_epi32(x, aes_make_block(0, 0, 0, 1));
+    x = reverse_byte_order(x);
+    return x;
+}
+
+AES_StatusCode aes_format_block(
+    AES_BlockString* str,
+    const AES_Block* block,
+    AES_ErrorDetails* err_details
+) {
+    assert(str);
+    assert(block);
+
+    if (str == NULL)
+        return aes_error_null_argument(err_details, "str");
+    if (block == NULL)
+        return aes_error_null_argument(err_details, "block");
+
+    char* cursor = str->str;
+
+    AES_ALIGN(unsigned char, 16) bytes[16];
+    aes_store_block_aligned(bytes, *block);
+
+    for (int i = 0; i < 16; ++i, cursor += 2)
+        sprintf(cursor, "%02x", bytes[i]);
+
+    *cursor = '\0';
+    return AES_SUCCESS;
+}
+
+AES_StatusCode aes_format_block_as_matrix(
+    AES_BlockMatrixString* str,
+    const AES_Block* block,
+    AES_ErrorDetails* err_details
+) {
+    assert(str);
+    assert(block);
+
+    if (str == NULL)
+        return aes_error_null_argument(err_details, "str");
+    if (block == NULL)
+        return aes_error_null_argument(err_details, "block");
+
+    char* cursor = str->str;
+
+    AES_ALIGN(unsigned char, 16) bytes[4][4];
+    aes_store_block_aligned(bytes, *block);
+
+    for (int i = 0; i < 4; ++i, cursor += 3) {
+        for (int j = 0; j < 3; ++j, cursor += 3)
+            sprintf(cursor, "%02x ", bytes[j][i]);
+        sprintf(cursor, "%02x\n", bytes[3][i]);
+    }
+
+    *cursor = '\0';
+    return AES_SUCCESS;
+}
+
+AES_StatusCode aes_parse_block(AES_Block* dest, const char* src, AES_ErrorDetails* err_details) {
+    assert(dest);
+    assert(src);
+
+    if (dest == NULL)
+        return aes_error_null_argument(err_details, "dest");
+    if (src == NULL)
+        return aes_error_null_argument(err_details, "src");
+
+    const char* cursor = src;
+
+    AES_ALIGN(unsigned char, 16) bytes[16];
+
+    for (int i = 0; i < 16; ++i) {
+        int n;
+        unsigned int byte;
+        if (sscanf(cursor, "%2x%n", &byte, &n) != 1)
+            return aes_error_parse(err_details, src, "a 128-bit block");
+        bytes[i] = (unsigned char)byte;
+        cursor += n;
+    }
+
+    *dest = aes_load_block_aligned(bytes);
+    return AES_SUCCESS;
+}