playing around with AES

Makefile

@@ -0,0 +1,2 @@
+aesfun: aesfun.o aes_core.o
+	${CC} ${CFLAGS} -o $@ aesfun.o aes_core.o

aes_local.h

@@ -0,0 +1,83 @@
+/* $OpenBSD: aes_local.h,v 1.2 2022/11/26 17:23:17 tb Exp $ */
+/* ====================================================================
+ * Copyright (c) 1998-2002 The OpenSSL Project.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer. 
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. All advertising materials mentioning features or use of this
+ *    software must display the following acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ *    endorse or promote products derived from this software without
+ *    prior written permission. For written permission, please contact
+ *    openssl-core@openssl.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ *    nor may "OpenSSL" appear in their names without prior written
+ *    permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ *    acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ====================================================================
+ *
+ */
+
+#ifndef HEADER_AES_LOCAL_H
+#define HEADER_AES_LOCAL_H
+
+#include <openssl/opensslconf.h>
+
+#ifdef OPENSSL_NO_AES
+#error AES is disabled.
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+__BEGIN_HIDDEN_DECLS
+
+#define GETU32(pt) (((u32)(pt)[0] << 24) ^ ((u32)(pt)[1] << 16) ^ ((u32)(pt)[2] <<  8) ^ ((u32)(pt)[3]))
+#define PUTU32(ct, st) { (ct)[0] = (u8)((st) >> 24); (ct)[1] = (u8)((st) >> 16); (ct)[2] = (u8)((st) >>  8); (ct)[3] = (u8)(st); }
+
+typedef unsigned int u32;
+typedef unsigned short u16;
+typedef unsigned char u8;
+
+#define MAXKC   (256/32)
+#define MAXKB   (256/8)
+#define MAXNR   14
+
+/* This controls loop-unrolling in aes_core.c */
+#undef FULL_UNROLL
+
+__END_HIDDEN_DECLS
+
+#endif /* !HEADER_AES_LOCAL_H */

aesfun.c

@@ -0,0 +1,40 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <openssl/aes.h>
+
+int
+main()
+{
+	unsigned char userKey[32];
+	AES_KEY key;
+	unsigned char text[16];
+
+	arc4random_buf(userKey, sizeof(userKey));
+	printf("key: %02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x"
+		"%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x\n",
+		userKey[0], userKey[1], userKey[2], userKey[3], userKey[4], userKey[5], userKey[6], userKey[7],
+		userKey[8], userKey[9], userKey[10], userKey[11], userKey[12], userKey[13], userKey[14], userKey[15],
+		userKey[16], userKey[17], userKey[18], userKey[19], userKey[20], userKey[21], userKey[22], userKey[23],
+		userKey[24], userKey[25], userKey[26], userKey[27], userKey[28], userKey[29], userKey[30], userKey[31]);
+	AES_set_encrypt_key(userKey, 256, &key);
+
+	arc4random_buf(text, sizeof(text));
+	printf("plaintext: %02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x\n",
+		text[0], text[1], text[2], text[3], text[4], text[5], text[6], text[7],
+		text[8], text[9], text[10], text[11], text[12], text[13], text[14], text[15]);
+	AES_encrypt(text, text, &key);
+	printf("ciphertext: %02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x\n",
+		text[0], text[1], text[2], text[3], text[4], text[5], text[6], text[7],
+		text[8], text[9], text[10], text[11], text[12], text[13], text[14], text[15]);
+
+	arc4random_buf(text, sizeof(text));
+	printf("plaintext: %02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x\n",
+		text[0], text[1], text[2], text[3], text[4], text[5], text[6], text[7],
+		text[8], text[9], text[10], text[11], text[12], text[13], text[14], text[15]);
+	AES_encrypt(text, text, &key);
+	printf("ciphertext: %02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x\n",
+		text[0], text[1], text[2], text[3], text[4], text[5], text[6], text[7],
+		text[8], text[9], text[10], text[11], text[12], text[13], text[14], text[15]);
+
+	return 0;
+}