From 6e99bb203fa710333d3498adb2b1fdb5e01aadcd Mon Sep 17 00:00:00 2001 From: David Horstmann Date: Tue, 6 Feb 2024 15:27:49 +0000 Subject: [PATCH 1/4] Add buffer copying to psa_generate_random() Signed-off-by: David Horstmann --- library/psa_crypto.c | 98 +++++++++++++++++++++++++++----------------- 1 file changed, 60 insertions(+), 38 deletions(-) diff --git a/library/psa_crypto.c b/library/psa_crypto.c index 5b7a838a50..16e3447fa7 100644 --- a/library/psa_crypto.c +++ b/library/psa_crypto.c @@ -4190,6 +4190,54 @@ psa_status_t mbedtls_psa_verify_hash_abort( * defined( MBEDTLS_ECP_RESTARTABLE ) */ } +static psa_status_t psa_generate_random_internal(uint8_t *output, + size_t output_size) +{ + GUARD_MODULE_INITIALIZED; + + psa_status_t status; + +#if defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG) + + size_t output_length = 0; + status = mbedtls_psa_external_get_random(&global_data.rng, + output, output_size, + &output_length); + if (status != PSA_SUCCESS) { + goto exit; + } + /* Breaking up a request into smaller chunks is currently not supported + * for the external RNG interface. */ + if (output_length != output_size) { + status = PSA_ERROR_INSUFFICIENT_ENTROPY; + goto exit; + } + status = PSA_SUCCESS; + +#else /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */ + + while (output_size > 0) { + size_t request_size = + (output_size > MBEDTLS_PSA_RANDOM_MAX_REQUEST ? + MBEDTLS_PSA_RANDOM_MAX_REQUEST : + output_size); + int ret = mbedtls_psa_get_random(MBEDTLS_PSA_RANDOM_STATE, + output, request_size); + if (ret != 0) { + status = mbedtls_to_psa_error(ret); + goto exit; + } + output_size -= request_size; + output += request_size; + } + status = PSA_SUCCESS; +#endif /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */ + +exit: + return status; +} + + /****************************************************************/ /* Symmetric cryptography */ /****************************************************************/ @@ -4308,7 +4356,7 @@ psa_status_t psa_cipher_generate_iv(psa_cipher_operation_t *operation, goto exit; } - status = psa_generate_random(local_iv, default_iv_length); + status = psa_generate_random_internal(local_iv, default_iv_length); if (status != PSA_SUCCESS) { goto exit; } @@ -4497,7 +4545,7 @@ psa_status_t psa_cipher_encrypt(mbedtls_svc_key_id_t key, goto exit; } - status = psa_generate_random(local_iv, default_iv_length); + status = psa_generate_random_internal(local_iv, default_iv_length); if (status != PSA_SUCCESS) { goto exit; } @@ -5003,7 +5051,7 @@ psa_status_t psa_aead_generate_nonce(psa_aead_operation_t *operation, goto exit; } - status = psa_generate_random(local_nonce, required_nonce_size); + status = psa_generate_random_internal(local_nonce, required_nonce_size); if (status != PSA_SUCCESS) { goto exit; } @@ -7517,7 +7565,7 @@ exit: * some constant data such as zeros, which would result in the data * being protected with a reproducible, easily knowable key. */ - psa_generate_random(output, output_size); + psa_generate_random_internal(output, output_size); *output_length = output_size; } @@ -7527,7 +7575,6 @@ exit: } - /****************************************************************/ /* Random generation */ /****************************************************************/ @@ -7596,44 +7643,19 @@ static psa_status_t mbedtls_psa_random_seed(mbedtls_psa_random_context_t *rng) #endif /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */ } -psa_status_t psa_generate_random(uint8_t *output, +psa_status_t psa_generate_random(uint8_t *output_external, size_t output_size) { - GUARD_MODULE_INITIALIZED; + psa_status_t status; -#if defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG) + LOCAL_OUTPUT_DECLARE(output_external, output); + LOCAL_OUTPUT_ALLOC(output_external, output_size, output); - size_t output_length = 0; - psa_status_t status = mbedtls_psa_external_get_random(&global_data.rng, - output, output_size, - &output_length); - if (status != PSA_SUCCESS) { - return status; - } - /* Breaking up a request into smaller chunks is currently not supported - * for the external RNG interface. */ - if (output_length != output_size) { - return PSA_ERROR_INSUFFICIENT_ENTROPY; - } - return PSA_SUCCESS; + status = psa_generate_random_internal(output, output_size); -#else /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */ - - while (output_size > 0) { - size_t request_size = - (output_size > MBEDTLS_PSA_RANDOM_MAX_REQUEST ? - MBEDTLS_PSA_RANDOM_MAX_REQUEST : - output_size); - int ret = mbedtls_psa_get_random(MBEDTLS_PSA_RANDOM_STATE, - output, request_size); - if (ret != 0) { - return mbedtls_to_psa_error(ret); - } - output_size -= request_size; - output += request_size; - } - return PSA_SUCCESS; -#endif /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */ +exit: + LOCAL_OUTPUT_FREE(output_external, output); + return status; } /* Wrapper function allowing the classic API to use the PSA RNG. From 075c5fb76fd7e5f92e44fc25d61c44654962c49b Mon Sep 17 00:00:00 2001 From: David Horstmann Date: Tue, 6 Feb 2024 15:44:08 +0000 Subject: [PATCH 2/4] Generate test wrappers for psa_generate_random() Signed-off-by: David Horstmann --- tests/scripts/generate_psa_wrappers.py | 2 ++ tests/src/psa_test_wrappers.c | 6 ++++++ 2 files changed, 8 insertions(+) diff --git a/tests/scripts/generate_psa_wrappers.py b/tests/scripts/generate_psa_wrappers.py index cdc798db9e..a6c340cc1f 100755 --- a/tests/scripts/generate_psa_wrappers.py +++ b/tests/scripts/generate_psa_wrappers.py @@ -163,6 +163,8 @@ class PSAWrapperGenerator(c_wrapper_generator.Base): 'psa_hash_verify', 'psa_hash_compute', 'psa_hash_compare'): + + if function_name == 'psa_generate_random': return True return False diff --git a/tests/src/psa_test_wrappers.c b/tests/src/psa_test_wrappers.c index 5f0a3dd08c..fa9a8d6f02 100644 --- a/tests/src/psa_test_wrappers.c +++ b/tests/src/psa_test_wrappers.c @@ -542,7 +542,13 @@ psa_status_t mbedtls_test_wrap_psa_generate_random( uint8_t *arg0_output, size_t arg1_output_size) { +#if defined(MBEDTLS_PSA_COPY_CALLER_BUFFERS) + MBEDTLS_TEST_MEMORY_POISON(arg0_output, arg1_output_size); +#endif /* defined(MBEDTLS_PSA_COPY_CALLER_BUFFERS) */ psa_status_t status = (psa_generate_random)(arg0_output, arg1_output_size); +#if defined(MBEDTLS_PSA_COPY_CALLER_BUFFERS) + MBEDTLS_TEST_MEMORY_UNPOISON(arg0_output, arg1_output_size); +#endif /* defined(MBEDTLS_PSA_COPY_CALLER_BUFFERS) */ return status; } From e097bbdcf3f4d489adea1b0dec425b0cf9d2a84b Mon Sep 17 00:00:00 2001 From: David Horstmann Date: Wed, 28 Feb 2024 14:17:10 +0000 Subject: [PATCH 3/4] Add missing guards around exit label Signed-off-by: David Horstmann --- library/psa_crypto.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/library/psa_crypto.c b/library/psa_crypto.c index 16e3447fa7..e0ae088b76 100644 --- a/library/psa_crypto.c +++ b/library/psa_crypto.c @@ -7653,7 +7653,9 @@ psa_status_t psa_generate_random(uint8_t *output_external, status = psa_generate_random_internal(output, output_size); +#if defined(MBEDTLS_PSA_COPY_CALLER_BUFFERS) exit: +#endif LOCAL_OUTPUT_FREE(output_external, output); return status; } From 7581363122d7e441c5db79c324a25e75e1025b00 Mon Sep 17 00:00:00 2001 From: David Horstmann Date: Wed, 28 Feb 2024 15:16:44 +0000 Subject: [PATCH 4/4] Fix incorrect conflict resolution A return statement was missing in the wrapper generation script. Signed-off-by: David Horstmann --- tests/scripts/generate_psa_wrappers.py | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tests/scripts/generate_psa_wrappers.py b/tests/scripts/generate_psa_wrappers.py index a6c340cc1f..852fd6e7fa 100755 --- a/tests/scripts/generate_psa_wrappers.py +++ b/tests/scripts/generate_psa_wrappers.py @@ -163,7 +163,7 @@ class PSAWrapperGenerator(c_wrapper_generator.Base): 'psa_hash_verify', 'psa_hash_compute', 'psa_hash_compare'): - + return True if function_name == 'psa_generate_random': return True return False