Fix {sign|verify}_get_num_ops
Move the obfuscation of the internal library only returning a delta of ops done
into the driver wrapper, thus meaning driver wrapper and API call both return
absolute values of work done. Document the differences at the internal
implementation level.
Signed-off-by: Paul Elliott <paul.elliott@arm.com>
diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index d3ac4ce..419be16 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -3286,7 +3286,7 @@
exit:
/* Update ops count with work done. */
- operation->num_ops += psa_driver_wrapper_sign_hash_get_num_ops(operation);
+ operation->num_ops = psa_driver_wrapper_sign_hash_get_num_ops(operation);
if (status != PSA_OPERATION_INCOMPLETE) {
psa_wipe_output_buffer(signature, status, signature_size,
@@ -3413,7 +3413,7 @@
exit:
/* Update ops count with work done. */
- operation->num_ops += psa_driver_wrapper_verify_hash_get_num_ops(
+ operation->num_ops = psa_driver_wrapper_verify_hash_get_num_ops(
operation);
if (status != PSA_OPERATION_INCOMPLETE) {
diff --git a/library/psa_crypto_core.h b/library/psa_crypto_core.h
index f74db70..a007289 100644
--- a/library/psa_crypto_core.h
+++ b/library/psa_crypto_core.h
@@ -638,45 +638,45 @@
uint32_t mbedtls_psa_interruptible_get_max_ops(void);
/**
- * \brief Get the number of ops that a hash signing operation has taken so
- * far. If the operation has completed, then this will represent the
- * number of ops required for the entire operation. After initialization
- * or calling psa_sign_hash_interruptible_abort() on the operation, a
- * value of 0 will be returned.
+ * \brief Get the number of ops that a hash signing operation has taken for the
+ * previous call. If no call or work has taken place, this will return
+ * zero.
*
* \note The signature of this function is that of a PSA driver
- * sign_get_num_ops entry point. This function behaves as a
- * sign_get_num_ops entry point as defined in the PSA driver interface
- * specification for transparent drivers.
+ * sign_get_num_ops entry point, however it differs in behaviour from the
+ * driver function in that this function returns a delta of work done in
+ * the last call rather than all of the ops done ever by the whole
+ * operation, due to internal implementation differences.
*
* \param[in] operation The \c
* mbedtls_psa_sign_hash_interruptible_operation_t
* to use. This must be initialized first.
*
- * \return Number of ops that the operation has taken so
- * far.
+ * \return Number of ops that were completed
+ * in the last call to \c
+ * mbedtls_psa_sign_hash_complete().
*/
uint32_t mbedtls_psa_sign_hash_get_num_ops(
const mbedtls_psa_sign_hash_interruptible_operation_t *operation);
/**
- * \brief Get the number of ops that a hash verification operation has taken
- * so far. If the operation has completed, then this will represent the
- * number of ops required for the entire operation. After initialization
- * or calling psa_verify_hash_interruptible_abort() on the operation, a
- * value of 0 will be returned.
+ * \brief Get the number of ops that a hash verification operation has taken for
+ * the previous call. If no call or work has taken place, this will
+ * return zero.
*
* \note The signature of this function is that of a PSA driver
- * verify_get_num_ops entry point. This function behaves as a
- * verify_get_num_ops entry point as defined in the PSA driver interface
- * specification for transparent drivers.
+ * verify_get_num_ops entry point however it differs in behaviour from the
+ * driver function in that this function returns a delta of work done in
+ * the last call rather than all of the ops done ever by the whole
+ * operation, due to internal implementation differences.
*
* \param[in] operation The \c
* mbedtls_psa_verify_hash_interruptible_operation_t
* to use. This must be initialized first.
*
- * \return Number of ops that the operation has taken so
- * far.
+ * \return Number of ops that were completed
+ * in the last call to \c
+ * mbedtls_psa_verify_hash_complete().
*/
uint32_t mbedtls_psa_verify_hash_get_num_ops(
const mbedtls_psa_verify_hash_interruptible_operation_t *operation);
diff --git a/scripts/data_files/driver_templates/psa_crypto_driver_wrappers.c.jinja b/scripts/data_files/driver_templates/psa_crypto_driver_wrappers.c.jinja
index 2b2b025..fba8990 100644
--- a/scripts/data_files/driver_templates/psa_crypto_driver_wrappers.c.jinja
+++ b/scripts/data_files/driver_templates/psa_crypto_driver_wrappers.c.jinja
@@ -453,7 +453,11 @@
return 0;
case PSA_CRYPTO_MBED_TLS_DRIVER_ID:
- return( mbedtls_psa_sign_hash_get_num_ops(
+ /* Internal implementation returns a delta of ops completed in the
+ * last call to complete(), so need to add in ops already completed
+ * before this.*/
+ return( operation->num_ops +
+ mbedtls_psa_sign_hash_get_num_ops(
&operation->ctx.mbedtls_ctx )
);
@@ -478,7 +482,11 @@
return 0;
case PSA_CRYPTO_MBED_TLS_DRIVER_ID:
- return( mbedtls_psa_verify_hash_get_num_ops(
+ /* Internal implementation returns a delta of ops completed in the
+ * last call to complete(), so need to add in ops already completed
+ * before this.*/
+ return ( operation->num_ops +
+ mbedtls_psa_verify_hash_get_num_ops(
&operation->ctx.mbedtls_ctx )
);