lib/mbedtls
1
0
Fork 0
mirror of https://github.com/Mbed-TLS/mbedtls.git synced 2025-07-30 22:43:08 +03:00
Code Activity

Merge pull request #1181 from tom-daubney-arm/key_agreement_buffer_protection

Browse Source 
Implement safe buffer copying in key agreement
This commit is contained in:
David Horstmann
2024-03-11 15:10:49 +00:00
committed by GitHub
parent 849bb717bc d4c57c0ad2
commit 63dfb45e5e
4 changed files with 44 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

30
library/psa_crypto.c
View File

@ -7581,12 +7581,13 @@ exit:
psa_status_t psa_key_derivation_key_agreement(psa_key_derivation_operation_t *operation,
psa_key_derivation_step_t step,
mbedtls_svc_key_id_t private_key,
const uint8_t *peer_key,
const uint8_t *peer_key_external,
size_t peer_key_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot;
LOCAL_INPUT_DECLARE(peer_key_external, peer_key);
if (!PSA_ALG_IS_KEY_AGREEMENT(operation->alg)) {
return PSA_ERROR_INVALID_ARGUMENT;
@ -7596,9 +7597,15 @@ psa_status_t psa_key_derivation_key_agreement(psa_key_derivation_operation_t *op
if (status != PSA_SUCCESS) {
return status;
}
LOCAL_INPUT_ALLOC(peer_key_external, peer_key_length, peer_key)
status = psa_key_agreement_internal(operation, step,
slot,
peer_key, peer_key_length);
#if defined(MBEDTLS_PSA_COPY_CALLER_BUFFERS)
exit:
#endif
if (status != PSA_SUCCESS) {
psa_key_derivation_abort(operation);
} else {
@ -7610,15 +7617,15 @@ psa_status_t psa_key_derivation_key_agreement(psa_key_derivation_operation_t *op
}
unlock_status = psa_unregister_read(slot);
LOCAL_INPUT_FREE(peer_key_external, peer_key);
return (status == PSA_SUCCESS) ? unlock_status : status;
}
psa_status_t psa_raw_key_agreement(psa_algorithm_t alg,
mbedtls_svc_key_id_t private_key,
const uint8_t *peer_key,
const uint8_t *peer_key_external,
size_t peer_key_length,
uint8_t *output,
uint8_t *output_external,
size_t output_size,
size_t *output_length)
{
@ -7626,6 +7633,9 @@ psa_status_t psa_raw_key_agreement(psa_algorithm_t alg,
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot = NULL;
size_t expected_length;
LOCAL_INPUT_DECLARE(peer_key_external, peer_key);
LOCAL_OUTPUT_DECLARE(output_external, output);
LOCAL_OUTPUT_ALLOC(output_external, output_size, output);
if (!PSA_ALG_IS_KEY_AGREEMENT(alg)) {
status = PSA_ERROR_INVALID_ARGUMENT;
@ -7652,13 +7662,16 @@ psa_status_t psa_raw_key_agreement(psa_algorithm_t alg,
goto exit;
}
LOCAL_INPUT_ALLOC(peer_key_external, peer_key_length, peer_key);
status = psa_key_agreement_raw_internal(alg, slot,
peer_key, peer_key_length,
output, output_size,
output_length);
exit:
if (status != PSA_SUCCESS) {
/* Check for successful allocation of output,
* with an unsuccessful status. */
if (output != NULL && status != PSA_SUCCESS) {
/* If an error happens and is not handled properly, the output
* may be used as a key to protect sensitive data. Arrange for such
* a key to be random, which is likely to result in decryption or
@ -7670,8 +7683,15 @@ exit:
*output_length = output_size;
}
if (output == NULL) {
/* output allocation failed. */
*output_length = 0;
}
unlock_status = psa_unregister_read(slot);
LOCAL_INPUT_FREE(peer_key_external, peer_key);
LOCAL_OUTPUT_FREE(output_external, output);
return (status == PSA_SUCCESS) ? unlock_status : status;
}