Avoid duplicate program names
Visual Studio and CMake didn't like having targets with the same name,
albeit in different directories.
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
diff --git a/programs/cipher/cipher_aead_demo.c b/programs/cipher/cipher_aead_demo.c
new file mode 100644
index 0000000..4da1bfc
--- /dev/null
+++ b/programs/cipher/cipher_aead_demo.c
@@ -0,0 +1,264 @@
+/**
+ * Cipher API multi-part AEAD demonstration.
+ *
+ * This program AEAD-encrypts a message, using the algorithm and key size
+ * specified on the command line, using the multi-part API.
+ *
+ * It comes with a companion program psa/aead_demo.c, which does the same
+ * operations with the PSA Crypto API. The goal is that comparing the two
+ * programs will help people migrating to the PSA Crypto API.
+ *
+ * When used with multi-part AEAD operations, the `mbedtls_cipher_context`
+ * serves a triple purpose (1) hold the key, (2) store the algorithm when no
+ * operation is active, and (3) save progress information for the current
+ * operation. With PSA those roles are held by disinct objects: (1) a
+ * psa_key_id_t to hold the key, a (2) psa_algorithm_t to represent the
+ * algorithm, and (3) a psa_operation_t for multi-part progress.
+ *
+ * On the other hand, with PSA, the algorithms encodes the desired tag length;
+ * with Cipher the desired tag length needs to be tracked separately.
+ *
+ * This program and its companion psa/aead_demo.c illustrate this by doing the
+ * same sequence of multi-part AEAD computation with both APIs; looking at the
+ * two side by side should make the differences and similarities clear.
+ */
+
+/*
+ * Copyright The Mbed TLS Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* First include Mbed TLS headers to get the Mbed TLS configuration and
+ * platform definitions that we'll use in this program. Also include
+ * standard C headers for functions we'll use here. */
+#include "mbedtls/build_info.h"
+
+#include "mbedtls/cipher.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+/* If the build options we need are not enabled, compile a placeholder. */
+#if !defined(MBEDTLS_CIPHER_C) || \
+ !defined(MBEDTLS_AES_C) || !defined(MBEDTLS_GCM_C) || \
+ !defined(MBEDTLS_CHACHAPOLY_C)
+int main( void )
+{
+ printf( "MBEDTLS_MD_C and/or "
+ "MBEDTLS_AES_C and/or MBEDTLS_GCM_C and/or "
+ "MBEDTLS_CHACHAPOLY_C not defined\r\n" );
+ return( 0 );
+}
+#else
+
+/* The real program starts here. */
+
+const char usage[] = "Usage: cipher_aead_demo [aes128-gcm|aes256-gcm|aes128-gcm_8|chachapoly]";
+
+/* Dummy data for encryption: IV/nonce, additional data, 2-part message */
+const unsigned char iv1[12] = { 0x00 };
+const unsigned char add_data1[] = { 0x01, 0x02 };
+const unsigned char msg1_part1[] = { 0x03, 0x04 };
+const unsigned char msg1_part2[] = { 0x05, 0x06, 0x07 };
+
+/* Dummy data (2nd message) */
+const unsigned char iv2[12] = { 0x10 };
+const unsigned char add_data2[] = { 0x11, 0x12 };
+const unsigned char msg2_part1[] = { 0x13, 0x14 };
+const unsigned char msg2_part2[] = { 0x15, 0x16, 0x17 };
+
+/* This must at least the sum of the length of the 2 parts for each message.
+ * This is a macro for the sake of compilers with insufficient C99 support. */
+#define MSG_MAX_SIZE 5
+
+/* Dummy key material - never do this in production!
+ * 32-byte is enough to all the key size supported by this program. */
+const unsigned char key_bytes[32] = { 0x2a };
+
+/* Print the contents of a buffer in hex */
+void print_buf( const char *title, unsigned char *buf, size_t len )
+{
+ printf( "%s:", title );
+ for( size_t i = 0; i < len; i++ )
+ printf( " %02x", buf[i] );
+ printf( "\n" );
+}
+
+/* Run an Mbed TLS function and bail out if it fails. */
+#define CHK( expr ) \
+ do \
+ { \
+ ret = ( expr ); \
+ if( ret != 0 ) \
+ { \
+ printf( "Error %d at line %d: %s\n", \
+ ret, \
+ __LINE__, \
+ #expr ); \
+ goto exit; \
+ } \
+ } while( 0 )
+
+/*
+ * Prepare encryption material:
+ * - interpret command-line argument
+ * - set up key
+ * - outputs: context and tag length, which together hold all the information
+ */
+static int aead_prepare( const char *info,
+ mbedtls_cipher_context_t *ctx,
+ size_t *tag_len )
+{
+ int ret;
+
+ /* Convert arg to type + tag_len */
+ mbedtls_cipher_type_t type;
+ if( strcmp( info, "aes128-gcm" ) == 0 ) {
+ type = MBEDTLS_CIPHER_AES_128_GCM;
+ *tag_len = 16;
+ } else if( strcmp( info, "aes256-gcm" ) == 0 ) {
+ type = MBEDTLS_CIPHER_AES_256_GCM;
+ *tag_len = 16;
+ } else if( strcmp( info, "aes128-gcm_8" ) == 0 ) {
+ type = MBEDTLS_CIPHER_AES_128_GCM;
+ *tag_len = 8;
+ } else if( strcmp( info, "chachapoly" ) == 0 ) {
+ type = MBEDTLS_CIPHER_CHACHA20_POLY1305;
+ *tag_len = 16;
+ } else {
+ puts( usage );
+ return( MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA );
+ }
+
+ /* Prepare context for the given type */
+ CHK( mbedtls_cipher_setup( ctx,
+ mbedtls_cipher_info_from_type( type ) ) );
+
+ /* Import key */
+ int key_len = mbedtls_cipher_get_key_bitlen( ctx );
+ CHK( mbedtls_cipher_setkey( ctx, key_bytes, key_len, MBEDTLS_ENCRYPT ) );
+
+exit:
+ return( ret );
+}
+
+/*
+ * Print out some information.
+ *
+ * All of this information was present in the command line argument, but his
+ * function demonstrates how each piece can be recovered from (ctx, tag_len).
+ */
+static void aead_info( const mbedtls_cipher_context_t *ctx, size_t tag_len )
+{
+ // no convenient way to get the just cipher type (for example, AES)
+ const char *ciph = "???";
+ int key_bits = mbedtls_cipher_get_key_bitlen( ctx );
+ mbedtls_cipher_mode_t mode = mbedtls_cipher_get_cipher_mode( ctx );
+
+ const char *mode_str = mode == MBEDTLS_MODE_GCM ? "GCM"
+ : mode == MBEDTLS_MODE_CHACHAPOLY ? "ChachaPoly"
+ : "???";
+
+ printf( "cipher: %s, %d, %s, %u\n", ciph, key_bits, mode_str, (unsigned) tag_len );
+}
+
+/*
+ * Encrypt a 2-part message.
+ */
+static int aead_encrypt( mbedtls_cipher_context_t *ctx, size_t tag_len,
+ const unsigned char *iv, size_t iv_len,
+ const unsigned char *ad, size_t ad_len,
+ const unsigned char *pa, size_t pa_len,
+ const unsigned char *pb, size_t pb_len )
+{
+ int ret;
+ size_t olen;
+ unsigned char out[MSG_MAX_SIZE + 16];
+ unsigned char *p = out;
+
+ CHK( mbedtls_cipher_set_iv( ctx, iv, iv_len ) );
+ CHK( mbedtls_cipher_reset( ctx ) );
+ CHK( mbedtls_cipher_update_ad( ctx, ad, ad_len ) );
+ CHK( mbedtls_cipher_update( ctx, pa, pa_len, p, &olen ) );
+ p += olen;
+ CHK( mbedtls_cipher_update( ctx, pb, pb_len, p, &olen ) );
+ p += olen;
+ CHK( mbedtls_cipher_finish( ctx, p, &olen ) );
+ p += olen;
+ CHK( mbedtls_cipher_write_tag( ctx, p, tag_len ) );
+ p += tag_len;
+
+ olen = p - out;
+ print_buf( "cipher", out, olen );
+
+exit:
+ return( ret );
+}
+
+/*
+ * AEAD demo: set up key/alg, print out info, encrypt messages.
+ */
+static int aead_demo( const char *info )
+{
+ int ret = 0;
+
+ mbedtls_cipher_context_t ctx;
+ size_t tag_len;
+
+ mbedtls_cipher_init( &ctx );
+
+ CHK( aead_prepare( info, &ctx, &tag_len ) );
+
+ aead_info( &ctx, tag_len );
+
+ CHK( aead_encrypt( &ctx, tag_len,
+ iv1, sizeof( iv1 ), add_data1, sizeof( add_data1 ),
+ msg1_part1, sizeof( msg1_part1 ),
+ msg1_part2, sizeof( msg1_part2 ) ) );
+ CHK( aead_encrypt( &ctx, tag_len,
+ iv2, sizeof( iv2 ), add_data2, sizeof( add_data2 ),
+ msg2_part1, sizeof( msg2_part1 ),
+ msg2_part2, sizeof( msg2_part2 ) ) );
+
+exit:
+ mbedtls_cipher_free( &ctx );
+
+ return( ret );
+}
+
+
+/*
+ * Main function
+ */
+int main( int argc, char **argv )
+{
+ /* Check usage */
+ if( argc != 2 )
+ {
+ puts( usage );
+ return( 1 );
+ }
+
+ int ret;
+
+ /* Run the demo */
+ CHK( aead_demo( argv[1] ) );
+
+exit:
+ return( ret == 0 ? EXIT_SUCCESS : EXIT_FAILURE );
+}
+
+#endif