From 65bf12ce6b0239974db31ba6c67d20f902fa564b 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 | 94 +++++++++++++++++++++++++++----------------- 1 file changed, 57 insertions(+), 37 deletions(-) diff --git a/library/psa_crypto.c b/library/psa_crypto.c index f9fab4808..19daee957 100644 --- a/library/psa_crypto.c +++ b/library/psa_crypto.c @@ -3528,6 +3528,52 @@ exit: return (status == PSA_SUCCESS) ? unlock_status : status; } +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; +} /****************************************************************/ @@ -3650,7 +3696,7 @@ 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; } @@ -3839,7 +3885,7 @@ 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; } @@ -5367,7 +5413,7 @@ 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; } @@ -5377,7 +5423,6 @@ exit: } - /****************************************************************/ /* Random generation */ /****************************************************************/ @@ -5446,44 +5491,19 @@ 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 4e8215057c4dfb2ea38dce1b3214f40ea6566665 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 4f567bcfe..0aaa7104e 100755 --- a/tests/scripts/generate_psa_wrappers.py +++ b/tests/scripts/generate_psa_wrappers.py @@ -171,6 +171,8 @@ 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 032df8d28..1efa1bb6a 100644 --- a/tests/src/psa_test_wrappers.c +++ b/tests/src/psa_test_wrappers.c @@ -326,7 +326,13 @@ 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 10e44f3fd172d0381709ad274a7d56ac9e2a0c3a 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 19daee957..5c1a98db6 100644 --- a/library/psa_crypto.c +++ b/library/psa_crypto.c @@ -5501,7 +5501,9 @@ 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 80de1475a1eb935822a9377ef8f73583ac6aee26 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 0aaa7104e..db7a55951 100755 --- a/tests/scripts/generate_psa_wrappers.py +++ b/tests/scripts/generate_psa_wrappers.py @@ -171,7 +171,7 @@ 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