Merge pull request #5436 from mpg/prog-hmac-cipher-psa
PSA: example programs for HMAC and AEAD vs legacy
diff --git a/programs/.gitignore b/programs/.gitignore
index 550239e..44e904a 100644
--- a/programs/.gitignore
+++ b/programs/.gitignore
@@ -13,8 +13,10 @@
*.exe
aes/crypt_and_hash
+cipher/cipher_aead_demo
hash/generic_sum
hash/hello
+hash/md_hmac_demo
hash/md5sum
hash/sha1sum
hash/sha2sum
@@ -38,7 +40,9 @@
pkey/rsa_sign_pss
pkey/rsa_verify
pkey/rsa_verify_pss
+psa/aead_demo
psa/crypto_examples
+psa/hmac_demo
psa/key_ladder_demo
psa/psa_constant_names
random/gen_entropy
diff --git a/programs/CMakeLists.txt b/programs/CMakeLists.txt
index a8492c6..0633aa6 100644
--- a/programs/CMakeLists.txt
+++ b/programs/CMakeLists.txt
@@ -1,4 +1,5 @@
add_subdirectory(aes)
+add_subdirectory(cipher)
if (NOT WIN32)
add_subdirectory(fuzz)
endif()
diff --git a/programs/Makefile b/programs/Makefile
index 1ebf8d2..fdfece7 100644
--- a/programs/Makefile
+++ b/programs/Makefile
@@ -80,8 +80,10 @@
## make sure to check that it still works if you tweak the format here.
APPS = \
aes/crypt_and_hash \
+ cipher/cipher_aead_demo \
hash/generic_sum \
hash/hello \
+ hash/md_hmac_demo \
pkey/dh_client \
pkey/dh_genprime \
pkey/dh_server \
@@ -102,7 +104,9 @@
pkey/rsa_sign_pss \
pkey/rsa_verify \
pkey/rsa_verify_pss \
+ psa/aead_demo \
psa/crypto_examples \
+ psa/hmac_demo \
psa/key_ladder_demo \
psa/psa_constant_names \
random/gen_entropy \
@@ -195,14 +199,22 @@
echo " CC aes/crypt_and_hash.c"
$(CC) $(LOCAL_CFLAGS) $(CFLAGS) aes/crypt_and_hash.c $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
-hash/hello$(EXEXT): hash/hello.c $(DEP)
- echo " CC hash/hello.c"
- $(CC) $(LOCAL_CFLAGS) $(CFLAGS) hash/hello.c $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
+cipher/cipher_aead_demo$(EXEXT): cipher/cipher_aead_demo.c $(DEP)
+ echo " CC cipher/cipher_aead_demo.c"
+ $(CC) $(LOCAL_CFLAGS) $(CFLAGS) cipher/cipher_aead_demo.c $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
hash/generic_sum$(EXEXT): hash/generic_sum.c $(DEP)
echo " CC hash/generic_sum.c"
$(CC) $(LOCAL_CFLAGS) $(CFLAGS) hash/generic_sum.c $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
+hash/hello$(EXEXT): hash/hello.c $(DEP)
+ echo " CC hash/hello.c"
+ $(CC) $(LOCAL_CFLAGS) $(CFLAGS) hash/hello.c $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
+
+hash/md_hmac_demo$(EXEXT): hash/md_hmac_demo.c $(DEP)
+ echo " CC hash/md_hmac_demo.c"
+ $(CC) $(LOCAL_CFLAGS) $(CFLAGS) hash/md_hmac_demo.c $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
+
pkey/dh_client$(EXEXT): pkey/dh_client.c $(DEP)
echo " CC pkey/dh_client.c"
$(CC) $(LOCAL_CFLAGS) $(CFLAGS) pkey/dh_client.c $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
@@ -283,6 +295,18 @@
echo " CC pkey/rsa_encrypt.c"
$(CC) $(LOCAL_CFLAGS) $(CFLAGS) pkey/rsa_encrypt.c $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
+psa/aead_demo$(EXEXT): psa/aead_demo.c $(DEP)
+ echo " CC psa/aead_demo.c"
+ $(CC) $(LOCAL_CFLAGS) $(CFLAGS) psa/aead_demo.c $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
+
+psa/crypto_examples$(EXEXT): psa/crypto_examples.c $(DEP)
+ echo " CC psa/crypto_examples.c"
+ $(CC) $(LOCAL_CFLAGS) $(CFLAGS) psa/crypto_examples.c $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
+
+psa/hmac_demo$(EXEXT): psa/hmac_demo.c $(DEP)
+ echo " CC psa/hmac_demo.c"
+ $(CC) $(LOCAL_CFLAGS) $(CFLAGS) psa/hmac_demo.c $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
+
psa/key_ladder_demo$(EXEXT): psa/key_ladder_demo.c $(DEP)
echo " CC psa/key_ladder_demo.c"
$(CC) $(LOCAL_CFLAGS) $(CFLAGS) psa/key_ladder_demo.c $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
@@ -427,10 +451,6 @@
echo " CC x509/req_app.c"
$(CC) $(LOCAL_CFLAGS) $(CFLAGS) x509/req_app.c $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
-psa/crypto_examples$(EXEXT): psa/crypto_examples.c $(DEP)
- echo " CC psa/crypto_examples.c"
- $(CC) $(LOCAL_CFLAGS) $(CFLAGS) psa/crypto_examples.c $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
-
clean:
ifndef WINDOWS
rm -f $(EXES)
diff --git a/programs/cipher/CMakeLists.txt b/programs/cipher/CMakeLists.txt
new file mode 100644
index 0000000..93e5f31
--- /dev/null
+++ b/programs/cipher/CMakeLists.txt
@@ -0,0 +1,13 @@
+set(executables
+ cipher_aead_demo
+)
+
+foreach(exe IN LISTS executables)
+ add_executable(${exe} ${exe}.c $<TARGET_OBJECTS:mbedtls_test>)
+ target_link_libraries(${exe} ${mbedcrypto_target})
+ target_include_directories(${exe} PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/../../tests/include)
+endforeach()
+
+install(TARGETS ${executables}
+ DESTINATION "bin"
+ PERMISSIONS OWNER_READ OWNER_WRITE OWNER_EXECUTE GROUP_READ GROUP_EXECUTE WORLD_READ WORLD_EXECUTE)
diff --git a/programs/cipher/cipher_aead_demo.c b/programs/cipher/cipher_aead_demo.c
new file mode 100644
index 0000000..18bd66c
--- /dev/null
+++ b/programs/cipher/cipher_aead_demo.c
@@ -0,0 +1,271 @@
+/**
+ * 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 };
+
+/* Maximum total size of the messages */
+#define MSG1_SIZE ( sizeof( msg1_part1 ) + sizeof( msg1_part2 ) )
+#define MSG2_SIZE ( sizeof( msg2_part1 ) + sizeof( msg2_part2 ) )
+#define MSG_MAX_SIZE ( MSG1_SIZE > MSG2_SIZE ? MSG1_SIZE : MSG2_SIZE )
+
+/* 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.
+ * A string description of the error code can be recovered with:
+ * programs/util/strerror <value> */
+#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 )
+{
+ mbedtls_cipher_type_t type = mbedtls_cipher_get_type( ctx );
+ const mbedtls_cipher_info_t *info = mbedtls_cipher_info_from_type( type );
+ const char *ciph = mbedtls_cipher_info_get_name( info );
+ 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( "%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 *part1, size_t part1_len,
+ const unsigned char *part2, size_t part2_len )
+{
+ int ret;
+ size_t olen;
+#define MAX_TAG_LENGTH 16
+ unsigned char out[MSG_MAX_SIZE + MAX_TAG_LENGTH];
+ 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, part1, part1_len, p, &olen ) );
+ p += olen;
+ CHK( mbedtls_cipher_update( ctx, part2, part2_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( "out", 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
diff --git a/programs/hash/CMakeLists.txt b/programs/hash/CMakeLists.txt
index 729474c..da98188 100644
--- a/programs/hash/CMakeLists.txt
+++ b/programs/hash/CMakeLists.txt
@@ -1,6 +1,7 @@
set(executables
generic_sum
hello
+ md_hmac_demo
)
foreach(exe IN LISTS executables)
diff --git a/programs/hash/md_hmac_demo.c b/programs/hash/md_hmac_demo.c
new file mode 100644
index 0000000..d4cc3cc
--- /dev/null
+++ b/programs/hash/md_hmac_demo.c
@@ -0,0 +1,147 @@
+/**
+ * MD API multi-part HMAC demonstration.
+ *
+ * This programs computes the HMAC of two messages using the multi-part API.
+ *
+ * This is a companion to psa/hmac_demo.c, doing the same operations with the
+ * legacy MD API. The goal is that comparing the two programs will help people
+ * migrating to the PSA Crypto API.
+ *
+ * When it comes to multi-part HMAC operations, the `mbedtls_md_context`
+ * serves a dual purpose (1) hold the key, and (2) save progress information
+ * for the current operation. With PSA those roles are held by two disinct
+ * objects: (1) a psa_key_id_t to hold the key, and (2) a psa_operation_t for
+ * multi-part progress.
+ *
+ * This program and its companion psa/hmac_demo.c illustrate this by doing the
+ * same sequence of multi-part HMAC 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/md.h"
+
+#include "mbedtls/platform_util.h" // for mbedtls_platform_zeroize
+
+#include <stdlib.h>
+#include <stdio.h>
+
+/* If the build options we need are not enabled, compile a placeholder. */
+#if !defined(MBEDTLS_MD_C)
+int main( void )
+{
+ printf( "MBEDTLS_MD_C not defined\r\n" );
+ return( 0 );
+}
+#else
+
+/* The real program starts here. */
+
+/* Dummy inputs for HMAC */
+const unsigned char msg1_part1[] = { 0x01, 0x02 };
+const unsigned char msg1_part2[] = { 0x03, 0x04 };
+const unsigned char msg2_part1[] = { 0x05, 0x05 };
+const unsigned char msg2_part2[] = { 0x06, 0x06 };
+
+/* Dummy key material - never do this in production!
+ * This example program uses SHA-256, so a 32-byte key makes sense. */
+const unsigned char key_bytes[32] = { 0 };
+
+/* 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.
+ * A string description of the error code can be recovered with:
+ * programs/util/strerror <value> */
+#define CHK( expr ) \
+ do \
+ { \
+ ret = ( expr ); \
+ if( ret != 0 ) \
+ { \
+ printf( "Error %d at line %d: %s\n", \
+ ret, \
+ __LINE__, \
+ #expr ); \
+ goto exit; \
+ } \
+ } while( 0 )
+
+/*
+ * This function demonstrates computation of the HMAC of two messages using
+ * the multipart API.
+ */
+int hmac_demo(void)
+{
+ int ret;
+ const mbedtls_md_type_t alg = MBEDTLS_MD_SHA256;
+ unsigned char out[MBEDTLS_MD_MAX_SIZE]; // safe but not optimal
+
+ mbedtls_md_context_t ctx;
+
+ mbedtls_md_init( &ctx );
+
+ /* prepare context and load key */
+ // the last argument to setup is 1 to enable HMAC (not just hashing)
+ const mbedtls_md_info_t *info = mbedtls_md_info_from_type( alg );
+ CHK( mbedtls_md_setup( &ctx, info, 1 ) );
+ CHK( mbedtls_md_hmac_starts( &ctx, key_bytes, sizeof( key_bytes ) ) );
+
+ /* compute HMAC(key, msg1_part1 | msg1_part2) */
+ CHK( mbedtls_md_hmac_update( &ctx, msg1_part1, sizeof( msg1_part1 ) ) );
+ CHK( mbedtls_md_hmac_update( &ctx, msg1_part2, sizeof( msg1_part2 ) ) );
+ CHK( mbedtls_md_hmac_finish( &ctx, out ) );
+ print_buf( "msg1", out, mbedtls_md_get_size( info ) );
+
+ /* compute HMAC(key, msg2_part1 | msg2_part2) */
+ CHK( mbedtls_md_hmac_reset( &ctx ) ); // prepare for new operation
+ CHK( mbedtls_md_hmac_update( &ctx, msg2_part1, sizeof( msg2_part1 ) ) );
+ CHK( mbedtls_md_hmac_update( &ctx, msg2_part2, sizeof( msg2_part2 ) ) );
+ CHK( mbedtls_md_hmac_finish( &ctx, out ) );
+ print_buf( "msg2", out, mbedtls_md_get_size( info ) );
+
+exit:
+ mbedtls_md_free( &ctx );
+ mbedtls_platform_zeroize( out, sizeof( out ) );
+
+ return( ret );
+}
+
+int main(void)
+{
+ int ret;
+
+ CHK( hmac_demo() );
+
+exit:
+ return( ret == 0 ? EXIT_SUCCESS : EXIT_FAILURE );
+}
+
+#endif
diff --git a/programs/psa/CMakeLists.txt b/programs/psa/CMakeLists.txt
index 26ca73c..7ba4af6 100644
--- a/programs/psa/CMakeLists.txt
+++ b/programs/psa/CMakeLists.txt
@@ -1,5 +1,7 @@
set(executables
+ aead_demo
crypto_examples
+ hmac_demo
key_ladder_demo
psa_constant_names
)
diff --git a/programs/psa/aead_demo.c b/programs/psa/aead_demo.c
new file mode 100644
index 0000000..5bc0af0
--- /dev/null
+++ b/programs/psa/aead_demo.c
@@ -0,0 +1,293 @@
+/**
+ * PSA 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 cipher/cipher_aead_demo.c, which does the
+ * same operations with the legacy Cipher 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 cipher/cipher_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 "psa/crypto.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_PSA_CRYPTO_C) || \
+ !defined(MBEDTLS_AES_C) || !defined(MBEDTLS_GCM_C) || \
+ !defined(MBEDTLS_CHACHAPOLY_C) || \
+ defined(MBEDTLS_PSA_CRYPTO_KEY_ID_ENCODES_OWNER)
+int main( void )
+{
+ printf( "MBEDTLS_PSA_CRYPTO_C and/or "
+ "MBEDTLS_AES_C and/or MBEDTLS_GCM_C and/or "
+ "MBEDTLS_CHACHAPOLY_C not defined, and/or "
+ "MBEDTLS_PSA_CRYPTO_KEY_ID_ENCODES_OWNER defined\r\n" );
+ return( 0 );
+}
+#else
+
+/* The real program starts here. */
+
+const char usage[] =
+"Usage: 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 };
+
+/* Maximum total size of the messages */
+#define MSG1_SIZE ( sizeof( msg1_part1 ) + sizeof( msg1_part2 ) )
+#define MSG2_SIZE ( sizeof( msg2_part1 ) + sizeof( msg2_part2 ) )
+#define MSG_MAX_SIZE ( MSG1_SIZE > MSG2_SIZE ? MSG1_SIZE : MSG2_SIZE )
+
+/* 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, uint8_t *buf, size_t len )
+{
+ printf( "%s:", title );
+ for( size_t i = 0; i < len; i++ )
+ printf( " %02x", buf[i] );
+ printf( "\n" );
+}
+
+/* Run a PSA function and bail out if it fails.
+ * The symbolic name of the error code can be recovered using:
+ * programs/psa/psa_consant_name status <value> */
+#define PSA_CHECK( expr ) \
+ do \
+ { \
+ status = ( expr ); \
+ if( status != PSA_SUCCESS ) \
+ { \
+ printf( "Error %d at line %d: %s\n", \
+ (int) status, \
+ __LINE__, \
+ #expr ); \
+ goto exit; \
+ } \
+ } \
+ while( 0 )
+
+/*
+ * Prepare encryption material:
+ * - interpret command-line argument
+ * - set up key
+ * - outputs: key and algorithm, which together hold all the information
+ */
+static psa_status_t aead_prepare( const char *info,
+ psa_key_id_t *key,
+ psa_algorithm_t *alg )
+{
+ psa_status_t status;
+
+ /* Convert arg to alg + key_bits + key_type */
+ size_t key_bits;
+ psa_key_type_t key_type;
+ if( strcmp( info, "aes128-gcm" ) == 0 ) {
+ *alg = PSA_ALG_GCM;
+ key_bits = 128;
+ key_type = PSA_KEY_TYPE_AES;
+ } else if( strcmp( info, "aes256-gcm" ) == 0 ) {
+ *alg = PSA_ALG_GCM;
+ key_bits = 256;
+ key_type = PSA_KEY_TYPE_AES;
+ } else if( strcmp( info, "aes128-gcm_8" ) == 0 ) {
+ *alg = PSA_ALG_AEAD_WITH_SHORTENED_TAG(PSA_ALG_GCM, 8);
+ key_bits = 128;
+ key_type = PSA_KEY_TYPE_AES;
+ } else if( strcmp( info, "chachapoly" ) == 0 ) {
+ *alg = PSA_ALG_CHACHA20_POLY1305;
+ key_bits = 256;
+ key_type = PSA_KEY_TYPE_CHACHA20;
+ } else {
+ puts( usage );
+ return( PSA_ERROR_INVALID_ARGUMENT );
+ }
+
+ /* Prepare key attibutes */
+ psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
+ psa_set_key_usage_flags( &attributes, PSA_KEY_USAGE_ENCRYPT );
+ psa_set_key_algorithm( &attributes, *alg );
+ psa_set_key_type( &attributes, key_type );
+ psa_set_key_bits( &attributes, key_bits ); // optional
+
+ /* Import key */
+ PSA_CHECK( psa_import_key( &attributes, key_bytes, key_bits / 8, key ) );
+
+exit:
+ return( status );
+}
+
+/*
+ * 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 (key, alg).
+ */
+static void aead_info( psa_key_id_t key, psa_algorithm_t alg )
+{
+ psa_key_attributes_t attr = PSA_KEY_ATTRIBUTES_INIT;
+ (void) psa_get_key_attributes( key, &attr );
+ psa_key_type_t key_type = psa_get_key_type( &attr );
+ size_t key_bits = psa_get_key_bits( &attr );
+ psa_algorithm_t base_alg = PSA_ALG_AEAD_WITH_DEFAULT_LENGTH_TAG( alg );
+ size_t tag_len = PSA_AEAD_TAG_LENGTH( key_type, key_bits, alg );
+
+ const char *type_str = key_type == PSA_KEY_TYPE_AES ? "AES"
+ : key_type == PSA_KEY_TYPE_CHACHA20 ? "Chacha"
+ : "???";
+ const char *base_str = base_alg == PSA_ALG_GCM ? "GCM"
+ : base_alg == PSA_ALG_CHACHA20_POLY1305 ? "ChachaPoly"
+ : "???";
+
+ printf( "%s, %u, %s, %u\n",
+ type_str, (unsigned) key_bits, base_str, (unsigned) tag_len );
+}
+
+/*
+ * Encrypt a 2-part message.
+ */
+static int aead_encrypt( psa_key_id_t key, psa_algorithm_t alg,
+ const unsigned char *iv, size_t iv_len,
+ const unsigned char *ad, size_t ad_len,
+ const unsigned char *part1, size_t part1_len,
+ const unsigned char *part2, size_t part2_len )
+{
+ psa_status_t status;
+ size_t olen, olen_tag;
+ unsigned char out[PSA_AEAD_ENCRYPT_OUTPUT_MAX_SIZE(MSG_MAX_SIZE)];
+ unsigned char *p = out, *end = out + sizeof( out );
+ unsigned char tag[PSA_AEAD_TAG_MAX_SIZE];
+
+ psa_aead_operation_t op = PSA_AEAD_OPERATION_INIT;
+ PSA_CHECK( psa_aead_encrypt_setup( &op, key, alg ) );
+
+ PSA_CHECK( psa_aead_set_nonce( &op, iv, iv_len ) );
+ PSA_CHECK( psa_aead_update_ad( &op, ad, ad_len ) );
+ PSA_CHECK( psa_aead_update( &op, part1, part1_len, p, end - p, &olen ) );
+ p += olen;
+ PSA_CHECK( psa_aead_update( &op, part2, part2_len, p, end - p, &olen ) );
+ p += olen;
+ PSA_CHECK( psa_aead_finish( &op, p, end - p, &olen,
+ tag, sizeof( tag ), &olen_tag ) );
+ p += olen;
+ memcpy( p, tag, olen_tag );
+ p += olen_tag;
+
+ olen = p - out;
+ print_buf( "out", out, olen );
+
+exit:
+ psa_aead_abort( &op ); // required on errors, harmless on success
+ return( status );
+}
+
+/*
+ * AEAD demo: set up key/alg, print out info, encrypt messages.
+ */
+static psa_status_t aead_demo( const char *info )
+{
+ psa_status_t status;
+
+ psa_key_id_t key;
+ psa_algorithm_t alg;
+
+ PSA_CHECK( aead_prepare( info, &key, &alg ) );
+
+ aead_info( key, alg );
+
+ PSA_CHECK( aead_encrypt( key, alg,
+ iv1, sizeof( iv1 ), add_data1, sizeof( add_data1 ),
+ msg1_part1, sizeof( msg1_part1 ),
+ msg1_part2, sizeof( msg1_part2 ) ) );
+ PSA_CHECK( aead_encrypt( key, alg,
+ iv2, sizeof( iv2 ), add_data2, sizeof( add_data2 ),
+ msg2_part1, sizeof( msg2_part1 ),
+ msg2_part2, sizeof( msg2_part2 ) ) );
+
+exit:
+ psa_destroy_key( key );
+
+ return( status );
+}
+
+/*
+ * Main function
+ */
+int main( int argc, char **argv )
+{
+ psa_status_t status = PSA_SUCCESS;
+
+ /* Check usage */
+ if( argc != 2 )
+ {
+ puts( usage );
+ return( EXIT_FAILURE );
+ }
+
+ /* Initialize the PSA crypto library. */
+ PSA_CHECK( psa_crypto_init( ) );
+
+ /* Run the demo */
+ PSA_CHECK( aead_demo( argv[1] ) );
+
+ /* Deinitialize the PSA crypto library. */
+ mbedtls_psa_crypto_free( );
+
+exit:
+ return( status == PSA_SUCCESS ? EXIT_SUCCESS : EXIT_FAILURE );
+}
+
+#endif
diff --git a/programs/psa/hmac_demo.c b/programs/psa/hmac_demo.c
new file mode 100644
index 0000000..aa56b41
--- /dev/null
+++ b/programs/psa/hmac_demo.c
@@ -0,0 +1,169 @@
+/**
+ * PSA API multi-part HMAC demonstration.
+ *
+ * This programs computes the HMAC of two messages using the multi-part API.
+ *
+ * It comes with a companion program hash/md_hmac_demo.c, which does the same
+ * operations with the legacy MD API. The goal is that comparing the two
+ * programs will help people migrating to the PSA Crypto API.
+ *
+ * When it comes to multi-part HMAC operations, the `mbedtls_md_context`
+ * serves a dual purpose (1) hold the key, and (2) save progress information
+ * for the current operation. With PSA those roles are held by two disinct
+ * objects: (1) a psa_key_id_t to hold the key, and (2) a psa_operation_t for
+ * multi-part progress.
+ *
+ * This program and its companion hash/md_hmac_demo.c illustrate this by doing
+ * the same sequence of multi-part HMAC 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 "psa/crypto.h"
+
+#include "mbedtls/platform_util.h" // for mbedtls_platform_zeroize
+
+#include <stdlib.h>
+#include <stdio.h>
+
+/* If the build options we need are not enabled, compile a placeholder. */
+#if !defined(MBEDTLS_PSA_CRYPTO_C) || \
+ defined(MBEDTLS_PSA_CRYPTO_KEY_ID_ENCODES_OWNER)
+int main( void )
+{
+ printf( "MBEDTLS_PSA_CRYPTO_C not defined, "
+ "and/or MBEDTLS_PSA_CRYPTO_KEY_ID_ENCODES_OWNER defined\r\n" );
+ return( 0 );
+}
+#else
+
+/* The real program starts here. */
+
+/* Dummy inputs for HMAC */
+const unsigned char msg1_part1[] = { 0x01, 0x02 };
+const unsigned char msg1_part2[] = { 0x03, 0x04 };
+const unsigned char msg2_part1[] = { 0x05, 0x05 };
+const unsigned char msg2_part2[] = { 0x06, 0x06 };
+
+/* Dummy key material - never do this in production!
+ * This example program uses SHA-256, so a 32-byte key makes sense. */
+const unsigned char key_bytes[32] = { 0 };
+
+/* Print the contents of a buffer in hex */
+void print_buf( const char *title, uint8_t *buf, size_t len )
+{
+ printf( "%s:", title );
+ for( size_t i = 0; i < len; i++ )
+ printf( " %02x", buf[i] );
+ printf( "\n" );
+}
+
+/* Run a PSA function and bail out if it fails.
+ * The symbolic name of the error code can be recovered using:
+ * programs/psa/psa_consant_name status <value> */
+#define PSA_CHECK( expr ) \
+ do \
+ { \
+ status = ( expr ); \
+ if( status != PSA_SUCCESS ) \
+ { \
+ printf( "Error %d at line %d: %s\n", \
+ (int) status, \
+ __LINE__, \
+ #expr ); \
+ goto exit; \
+ } \
+ } \
+ while( 0 )
+
+/*
+ * This function demonstrates computation of the HMAC of two messages using
+ * the multipart API.
+ */
+psa_status_t hmac_demo(void)
+{
+ psa_status_t status;
+ const psa_algorithm_t alg = PSA_ALG_HMAC(PSA_ALG_SHA_256);
+ uint8_t out[PSA_MAC_MAX_SIZE]; // safe but not optimal
+ /* PSA_MAC_LENGTH(PSA_KEY_TYPE_HMAC, 8 * sizeof( key_bytes ), alg)
+ * should work but see https://github.com/ARMmbed/mbedtls/issues/4320 */
+
+ psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
+ psa_key_id_t key = 0;
+
+ /* prepare key */
+ psa_set_key_usage_flags( &attributes, PSA_KEY_USAGE_SIGN_MESSAGE );
+ psa_set_key_algorithm( &attributes, alg );
+ psa_set_key_type( &attributes, PSA_KEY_TYPE_HMAC );
+ psa_set_key_bits( &attributes, 8 * sizeof( key_bytes ) ); // optional
+
+ status = psa_import_key( &attributes,
+ key_bytes, sizeof( key_bytes ), &key );
+ if( status != PSA_SUCCESS )
+ return( status );
+
+ /* prepare operation */
+ psa_mac_operation_t op = PSA_MAC_OPERATION_INIT;
+ size_t out_len = 0;
+
+ /* compute HMAC(key, msg1_part1 | msg1_part2) */
+ PSA_CHECK( psa_mac_sign_setup( &op, key, alg ) );
+ PSA_CHECK( psa_mac_update( &op, msg1_part1, sizeof( msg1_part1 ) ) );
+ PSA_CHECK( psa_mac_update( &op, msg1_part2, sizeof( msg1_part2 ) ) );
+ PSA_CHECK( psa_mac_sign_finish( &op, out, sizeof( out ), &out_len ) );
+ print_buf( "msg1", out, out_len );
+
+ /* compute HMAC(key, msg2_part1 | msg2_part2) */
+ PSA_CHECK( psa_mac_sign_setup( &op, key, alg ) );
+ PSA_CHECK( psa_mac_update( &op, msg2_part1, sizeof( msg2_part1 ) ) );
+ PSA_CHECK( psa_mac_update( &op, msg2_part2, sizeof( msg2_part2 ) ) );
+ PSA_CHECK( psa_mac_sign_finish( &op, out, sizeof( out ), &out_len ) );
+ print_buf( "msg2", out, out_len );
+
+exit:
+ psa_mac_abort( &op ); // needed on error, harmless on success
+ psa_destroy_key( key );
+ mbedtls_platform_zeroize( out, sizeof( out ) );
+
+ return( status );
+}
+
+int main(void)
+{
+ psa_status_t status = PSA_SUCCESS;
+
+ /* Initialize the PSA crypto library. */
+ PSA_CHECK( psa_crypto_init( ) );
+
+ /* Run the demo */
+ PSA_CHECK( hmac_demo() );
+
+ /* Deinitialize the PSA crypto library. */
+ mbedtls_psa_crypto_free( );
+
+exit:
+ return( status == PSA_SUCCESS ? EXIT_SUCCESS : EXIT_FAILURE );
+}
+
+#endif