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Integrate p256-m as an example driver alongside Mbed TLS and write documentation for the example.

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(Reapplying changes as one commit on top of development post codestyle change instead of rewriting old branch)

Signed-off-by: Aditya Deshpande <aditya.deshpande@arm.com>
This commit is contained in:
Aditya Deshpande 2023-01-12 16:29:02 +00:00
parent 14d6b1124b
commit e41f7e457f
12 changed files with 2284 additions and 0 deletions
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THIRDPARTY_DIR = $(dir $(lastword $(MAKEFILE_LIST)))
include $(THIRDPARTY_DIR)/everest/Makefile.inc
include ../3rdparty/p256-m/Makefile.inc

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THIRDPARTY_INCLUDES+=-I../3rdparty/p256-m/p256-m/include -I../3rdparty/p256-m/p256-m/include/p256-m -I../3rdparty/p256-m/p256-m_driver_interface
THIRDPARTY_CRYPTO_OBJECTS+= \
../3rdparty/p256-m//p256-m_driver_entrypoints.o \
../3rdparty/p256-m//p256-m/p256-m.o

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/*
* Interface of curve P-256 (ECDH and ECDSA)
*
* Author: Manuel Pégourié-Gonnard.
* SPDX-License-Identifier: Apache-2.0
*/
#ifndef P256_M_H
#define P256_M_H
#include <stdint.h>
#include <stddef.h>
/* Status codes */
#define P256_SUCCESS 0
#define P256_RANDOM_FAILED -1
#define P256_INVALID_PUBKEY -2
#define P256_INVALID_PRIVKEY -3
#define P256_INVALID_SIGNATURE -4
#ifdef __cplusplus
extern "C" {
#endif
/*
* RNG function - must be provided externally and be cryptographically secure.
*
* in: output - must point to a writable buffer of at least output_size bytes.
* output_size - the number of random bytes to write to output.
* out: output is filled with output_size random bytes.
* return 0 on success, non-zero on errors.
*/
extern int p256_generate_random(uint8_t * output, unsigned output_size);
/*
* ECDH/ECDSA generate key pair
*
* [in] draws from p256_generate_random()
* [out] priv: on success, holds the private key, as a big-endian integer
* [out] pub: on success, holds the public key, as two big-endian integers
*
* return: P256_SUCCESS on success
* P256_RANDOM_FAILED on failure
*/
int p256_gen_keypair(uint8_t priv[32], uint8_t pub[64]);
/*
* ECDH compute shared secret
*
* [out] secret: on success, holds the shared secret, as a big-endian integer
* [in] priv: our private key as a big-endian integer
* [in] pub: the peer's public key, as two big-endian integers
*
* return: P256_SUCCESS on success
* P256_INVALID_PRIVKEY if priv is invalid
* P256_INVALID_PUBKEY if pub is invalid
*/
int p256_ecdh_shared_secret(uint8_t secret[32],
const uint8_t priv[32], const uint8_t pub[64]);
/*
* ECDSA sign
*
* [in] draws from p256_generate_random()
* [out] sig: on success, holds the signature, as two big-endian integers
* [in] priv: our private key as a big-endian integer
* [in] hash: the hash of the message to be signed
* [in] hlen: the size of hash in bytes
*
* return: P256_SUCCESS on success
* P256_RANDOM_FAILED on failure
* P256_INVALID_PRIVKEY if priv is invalid
*/
int p256_ecdsa_sign(uint8_t sig[64], const uint8_t priv[32],
const uint8_t *hash, size_t hlen);
/*
* ECDSA verify
*
* [in] sig: the signature to be verified, as two big-endian integers
* [in] pub: the associated public key, as two big-endian integers
* [in] hash: the hash of the message that was signed
* [in] hlen: the size of hash in bytes
*
* return: P256_SUCCESS on success - the signature was verified as valid
* P256_INVALID_PUBKEY if pub is invalid
* P256_INVALID_SIGNATURE if the signature was found to be invalid
*/
int p256_ecdsa_verify(const uint8_t sig[64], const uint8_t pub[64],
const uint8_t *hash, size_t hlen);
#ifdef __cplusplus
}
#endif
#endif /* P256_M_H */

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#include "mbedtls/platform.h"
#include "p256-m_driver_entrypoints.h"
#include "p256-m/p256-m.h"
#include "psa/crypto.h"
#include "psa_crypto_driver_wrappers.h"
#if defined(MBEDTLS_P256M_EXAMPLE_DRIVER_ENABLED)
psa_status_t p256m_to_psa_error( int ret )
{
switch( ret )
{
case P256_SUCCESS:
return( PSA_SUCCESS );
case P256_INVALID_PUBKEY:
case P256_INVALID_PRIVKEY:
return( PSA_ERROR_INVALID_ARGUMENT );
case P256_INVALID_SIGNATURE:
return( PSA_ERROR_INVALID_SIGNATURE );
case P256_RANDOM_FAILED:
default:
return( PSA_ERROR_GENERIC_ERROR );
}
}
psa_status_t p256m_transparent_generate_key(
const psa_key_attributes_t *attributes,
uint8_t *key_buffer,
size_t key_buffer_size,
size_t *key_buffer_length )
{
/* We don't use this argument, but the specification mandates the signature
* of driver entry-points. (void) used to avoid compiler warning. */
(void) attributes;
psa_status_t status = PSA_ERROR_NOT_SUPPORTED;
/*
* p256-m generates a 32 byte private key, and expects to write to a buffer
* that is of that size. */
if( key_buffer_size != 32 )
return( status );
/*
* p256-m's keypair generation function outputs both public and private
* keys. Allocate a buffer to which the public key will be written. The
* private key will be written to key_buffer, which is passed to this
* function as an argument. */
uint8_t *public_key_buffer = NULL;
public_key_buffer = mbedtls_calloc( 1, 64);
if( public_key_buffer == NULL)
return( PSA_ERROR_INSUFFICIENT_MEMORY );
status = p256m_to_psa_error(
p256_gen_keypair(key_buffer, public_key_buffer) );
if( status == PSA_SUCCESS )
*key_buffer_length = 32;
/*
* The storage format for a SECP256R1 keypair is just the private key, so
* the public key does not need to be passed back to the caller. Therefore
* the buffer containing it can be freed. */
free( public_key_buffer );
return status;
}
psa_status_t p256m_transparent_key_agreement(
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer,
size_t key_buffer_size,
psa_algorithm_t alg,
const uint8_t *peer_key,
size_t peer_key_length,
uint8_t *shared_secret,
size_t shared_secret_size,
size_t *shared_secret_length )
{
/* We don't use these arguments, but the specification mandates the
* sginature of driver entry-points. (void) used to avoid compiler
* warning. */
(void) attributes;
(void) alg;
/*
* Check that private key = 32 bytes, peer public key = 65 bytes,
* and that the shared secret buffer is big enough. */
psa_status_t status = PSA_ERROR_NOT_SUPPORTED;
if( key_buffer_size != 32 || shared_secret_size < 32 ||
peer_key_length != 65 )
return ( status );
status = p256m_to_psa_error(
p256_ecdh_shared_secret(shared_secret, key_buffer, peer_key+1) );
if( status == PSA_SUCCESS )
*shared_secret_length = 32;
return status;
}
psa_status_t p256m_transparent_sign_hash(
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer,
size_t key_buffer_size,
psa_algorithm_t alg,
const uint8_t *hash,
size_t hash_length,
uint8_t *signature,
size_t signature_size,
size_t *signature_length )
{
/* We don't use these arguments, but the specification mandates the
* sginature of driver entry-points. (void) used to avoid compiler
* warning. */
(void) attributes;
(void) alg;
psa_status_t status = PSA_ERROR_NOT_SUPPORTED;
if( key_buffer_size != 32 || signature_size != 64)
return( status );
status = p256m_to_psa_error(
p256_ecdsa_sign(signature, key_buffer, hash, hash_length) );
if( status == PSA_SUCCESS )
*signature_length = 64;
return status;
}
/* This function expects the key buffer to contain a 65 byte public key,
* as exported by psa_export_public_key() */
static psa_status_t p256m_verify_hash_with_public_key(
const uint8_t *key_buffer,
size_t key_buffer_size,
const uint8_t *hash,
size_t hash_length,
const uint8_t *signature,
size_t signature_length )
{
psa_status_t status = PSA_ERROR_NOT_SUPPORTED;
if( key_buffer_size != 65 || signature_length != 64 || *key_buffer != 0x04 )
return status;
const uint8_t *public_key_buffer = key_buffer + 1;
status = p256m_to_psa_error(
p256_ecdsa_verify( signature, public_key_buffer, hash, hash_length) );
return status;
}
psa_status_t p256m_transparent_verify_hash(
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer,
size_t key_buffer_size,
psa_algorithm_t alg,
const uint8_t *hash,
size_t hash_length,
const uint8_t *signature,
size_t signature_length )
{
/* We don't use this argument, but the specification mandates the signature
* of driver entry-points. (void) used to avoid compiler warning. */
(void) alg;
psa_status_t status;
uint8_t *public_key_buffer = NULL;
size_t public_key_buffer_size = 65;
public_key_buffer = mbedtls_calloc( 1, public_key_buffer_size);
if( public_key_buffer == NULL)
return( PSA_ERROR_INSUFFICIENT_MEMORY );
size_t *public_key_length = NULL;
public_key_length = mbedtls_calloc( 1, sizeof(size_t) );
if( public_key_length == NULL)
return( PSA_ERROR_INSUFFICIENT_MEMORY );
*public_key_length = 65;
/* The contents of key_buffer may either be the 32 byte private key
* (keypair representation), or the 65 byte public key. To ensure the
* latter is obtained, the public key is exported. */
status = psa_driver_wrapper_export_public_key(
attributes,
key_buffer,
key_buffer_size,
public_key_buffer,
public_key_buffer_size,
public_key_length );
if( status != PSA_SUCCESS )
goto exit;
status = p256m_verify_hash_with_public_key(
public_key_buffer,
public_key_buffer_size,
hash,
hash_length,
signature,
signature_length );
exit:
free( public_key_buffer );
free( public_key_length );
return ( status );
}
#endif /* MBEDTLS_P256M_EXAMPLE_DRIVER_ENABLED */

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#ifndef P256M_DRIVER_ENTRYPOINTS_H
#define P256M_DRIVER_ENTRYPOINTS_H
#if defined(MBEDTLS_P256M_EXAMPLE_DRIVER_ENABLED)
#ifndef PSA_CRYPTO_ACCELERATOR_DRIVER_PRESENT
#define PSA_CRYPTO_ACCELERATOR_DRIVER_PRESENT
#endif /* PSA_CRYPTO_ACCELERATOR_DRIVER_PRESENT */
#endif /* MBEDTLS_P256M_EXAMPLE_DRIVER_ENABLED */
#include "psa/crypto_types.h"
/** Convert an internal p256-m error code to a PSA error code
*
* \param ret An error code thrown by p256-m
*
* \return The corresponding PSA error code
*/
//no-check-names
psa_status_t p256m_to_psa_error( int ret );
/** Generate SECP256R1 ECC Key Pair.
* Interface function which calls the p256-m key generation function and
* places it in the key buffer provided by the caller (mbed TLS) in the
* correct format. For a SECP256R1 curve this is the 32 bit private key.
*
* \param[in] attributes The attributes of the key to use for the
* operation.
* \param[out] key_buffer The buffer to contain the key data in
* output format upon successful return.
* \param[in] key_buffer_size Size of the \p key_buffer buffer in bytes.
* \param[out] key_buffer_length The length of the data written in \p
* key_buffer in bytes.
*
* \retval #PSA_SUCCESS
* Success. Keypair generated and stored in buffer.
* \retval #PSA_ERROR_NOT_SUPPORTED
* \retval #PSA_ERROR_GENERIC_ERROR
* \retval #PSA_ERROR_INSUFFICIENT_MEMORY
*/
//no-check-names
psa_status_t p256m_transparent_generate_key(
const psa_key_attributes_t *attributes,
uint8_t *key_buffer,
size_t key_buffer_size,
size_t *key_buffer_length );
/** Perform raw key agreement using p256-m's ECDH implementation
* \param[in] attributes The attributes of the key to use for the
* operation.
* \param[in] key_buffer The buffer containing the private key
* in the format specified by PSA.
* \param[in] key_buffer_size Size of the \p key_buffer buffer in bytes.
* \param[in] alg A key agreement algorithm that is
* compatible with the type of the key.
* \param[in] peer_key The buffer containing the peer's public
* key in format specified by PSA.
* \param[in] peer_key_length Size of the \p peer_key buffer in
* bytes.
* \param[out] shared_secret The buffer to which the shared secret
* is to be written.
* \param[in] shared_secret_size Size of the \p shared_secret buffer in
* bytes.
* \param[out] shared_secret_length On success, the number of bytes that
* make up the returned shared secret.
* \retval #PSA_SUCCESS
* Success. Shared secret successfully calculated.
* \retval #PSA_ERROR_NOT_SUPPORTED
*/
//no-check-names
psa_status_t p256m_transparent_key_agreement(
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer,
size_t key_buffer_size,
psa_algorithm_t alg,
const uint8_t *peer_key,
size_t peer_key_length,
uint8_t *shared_secret,
size_t shared_secret_size,
size_t *shared_secret_length );
/** Sign an already-calculated hash with a private key using p256-m's ECDSA
* implementation
* \param[in] attributes The attributes of the key to use for the
* operation.
* \param[in] key_buffer The buffer containing the private key
* in the format specified by PSA.
* \param[in] key_buffer_size Size of the \p key_buffer buffer in bytes.
* \param[in] alg A signature algorithm that is compatible
* with the type of the key.
* \param[in] hash The hash to sign.
* \param[in] hash_length Size of the \p hash buffer in bytes.
* \param[out] signature Buffer where signature is to be written.
* \param[in] signature_size Size of the \p signature buffer in bytes.
* \param[out] signature_length On success, the number of bytes
* that make up the returned signature value.
*
* \retval #PSA_SUCCESS
* Success. Hash was signed successfully.
* respectively of the key.
* \retval #PSA_ERROR_NOT_SUPPORTED
*/
//no-check-names
psa_status_t p256m_transparent_sign_hash(
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer,
size_t key_buffer_size,
psa_algorithm_t alg,
const uint8_t *hash,
size_t hash_length,
uint8_t *signature,
size_t signature_size,
size_t *signature_length );
/** Verify the signature of a hash using a SECP256R1 public key using p256-m's
* ECDSA implementation.
*
* \note p256-m expects a 64 byte public key, but the contents of the key
buffer may be the 32 byte keypair representation or the 65 byte
public key representation. As a result, this function calls
psa_driver_wrapper_export_public_key() to ensure the public key
can be passed to p256-m.
*
* \param[in] attributes The attributes of the key to use for the
* operation.
*
* \param[in] key_buffer The buffer containing the key
* in the format specified by PSA.
* \param[in] key_buffer_size Size of the \p key_buffer buffer in bytes.
* \param[in] alg A signature algorithm that is compatible with
* the type of the key.
* \param[in] hash The hash whose signature is to be
* verified.
* \param[in] hash_length Size of the \p hash buffer in bytes.
* \param[in] signature Buffer containing the signature to verify.
* \param[in] signature_length Size of the \p signature buffer in bytes.
*
* \retval #PSA_SUCCESS
* The signature is valid.
* \retval #PSA_ERROR_INVALID_SIGNATURE
* The calculation was performed successfully, but the passed
* signature is not a valid signature.
* \retval #PSA_ERROR_NOT_SUPPORTED
*/
psa_status_t p256m_transparent_verify_hash(
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer,
size_t key_buffer_size,
psa_algorithm_t alg,
const uint8_t *hash,
size_t hash_length,
const uint8_t *signature,
size_t signature_length );
#endif /* P256M_DRIVER_ENTRYPOINTS_H */

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@ -0,0 +1,74 @@
# PSA Cryptoprocessor driver development examples
As of Mbed TLS 3.3.0, the PSA Driver Interface has only been partially implemented. As a result, the deliverables for writing a driver and the method for integrating a driver with Mbed TLS will vary depending on the operation being accelerated. This document describes how to write and integrate cryptoprocessor drivers depending on which operation or driver type is being implemented.
The `docs/proposed/` directory contains three documents which pertain to the proposed, work-in-progress driver system. The [PSA Driver Interface](https://github.com/Mbed-TLS/mbedtls/blob/development/docs/proposed/psa-driver-interface.md) describes how drivers will interface with Mbed TLS in the future, as well as driver types, operation types, and entry points. As many key terms and concepts used in the examples in this document are defined in the PSA Driver Interface, it is recommended that developers read it prior to starting work on implementing drivers.
The PSA Driver [Developer](https://github.com/Mbed-TLS/mbedtls/blob/development/docs/proposed/psa-driver-developer-guide.md) Guide describes the deliverables for writing a driver that can be used with Mbed TLS, and the PSA Driver [Integration](https://github.com/Mbed-TLS/mbedtls/blob/development/docs/proposed/psa-driver-integration-guide.md) Guide describes how a driver can be built alongside Mbed TLS.
## Background on how Mbed TLS calls drivers
The PSA Driver Interface specification specifies which cryptographic operations can be accelerated by third-party drivers. Operations that are completed within one step (one function call), such as verifying a signature, are called *Single-Part Operations*. On the other hand, operations that consist of multiple steps implemented by different functions called sequentially are called *Multi-Part Operations*. Single-part operations implemented by a driver will have one entry point, while multi-part operations will have multiple: one for each step.
There are two types of drivers: *transparent* or *opaque*. See below an excerpt from the PSA Driver Interface specification defining them:
* **Transparent** drivers implement cryptographic operations on keys that are provided in cleartext at the beginning of each operation. They are typically used for hardware **accelerators**. When a transparent driver is available for a particular combination of parameters (cryptographic algorithm, key type and size, etc.), it is used instead of the default software implementation. Transparent drivers can also be pure software implementations that are distributed as plug-ins to a PSA Cryptography implementation (for example, an alternative implementation with different performance characteristics, or a certified implementation).
* **Opaque** drivers implement cryptographic operations on keys that can only be used inside a protected environment such as a **secure element**, a hardware security module, a smartcard, a secure enclave, etc. An opaque driver is invoked for the specific [key location](https://github.com/Mbed-TLS/mbedtls/blob/development/docs/proposed/psa-driver-interface.md#lifetimes-and-locations) that the driver is registered for: the dispatch is based on the key's lifetime.
Mbed TLS contains a **driver dispatch layer** (also called a driver wrapper layer). For each cryptographic operation that supports driver acceleration (or sub-part of a multi-part operation), the library calls the corresponding function in the driver wrapper. Using flags set at compile time, the driver wrapper ascertains whether any present drivers support the operation. When no such driver is present, the built-in library implementation is called as a fallback (if allowed). When a compatible driver is present, the driver wrapper calls the driver entry point function provided by the driver author.
The long-term goal is for the driver dispatch layer to be auto-generated using a JSON driver description file provided by the driver author.
For some cryptographic operations, this auto-generation logic has already been implemented. When accelerating these operations, the instructions in the above documents can be followed. For the remaining operations which do not yet support auto-generation of the driver wrapper, developers will have to manually edit the driver dispatch layer and call their driver's entry point functions from there.
Auto-generation of the driver wrapper is supported for the operation entry points specified in the table below. Certain operations are only permitted for opaque drivers. All other operation entry points do not support auto-generation of the driver wrapper.
| Transparent Driver | Opaque Driver |
|---------------------|---------------------|
| `import_key` | `import_key` |
| `export_key` | `export_key` |
| `export_public_key` | `export_public_key` |
| | `copy_key` |
| | `get_builtin_key` |
### Process for Entry Points where auto-generation is implemented
If the driver is accelerating operations whose entry points are in the above table, the instructions in the driver [developer](https://github.com/Mbed-TLS/mbedtls/blob/development/docs/proposed/psa-driver-developer-guide.md) and [integration](https://github.com/Mbed-TLS/mbedtls/blob/development/docs/proposed/psa-driver-integration-guide.md) guides should be followed.
**TODO: Provide brief summary of the method using the Mbed TLS test driver as an example**
### Process for Entry Points where auto-generation is not implemented
If the driver is accelerating operations whose entry points are not present in the table, a different process is followed where the developer manually edits the driver dispatch layer. In general, the following steps must be taken **for each single-part operation** or **for each sub-part of a multi-part operation**:
**1. Choose a driver prefix and a macro name that indicates whether the driver is enabled** \
A driver prefix is simply a word (often the name of the driver) that all functions/macros associated with the driver should begin with. This is similar to how most functions/macros in Mbed TLS begin with `PSA_XXX/psa_xx` or `MBEDTLS_XXX/mbedtls_xxx`. The macro name can follow the form `DRIVER_PREFIX_ENABLED` or something similar; it will be used to indicate the driver is available to be called. When building with the driver present, define this macro at compile time. For example, when using `make`, this is done using the `-D` flag.
**2. Locate the function in the driver dispatch layer that corresponds to the entry point of the operation being accelerated.** \
The file `psa_crypto_driver_wrappers.c.jinja` contains the driver wrapper functions. For the entry points that have driver wrapper auto-generation implemented, the functions have been replaced with `jinja` templating logic. While the file has a `.jinja` extension, the driver wrapper functions for the remaining entry points are simple C functions. The names of these functions are of the form `psa_driver_wrapper` followed by the entry point name. So, for example, the function `psa_driver_wrapper_sign_hash()` corresponds to the `sign_hash` entry point.
**3. If a driver entry point function has been provided then ensure it has the same signature as the driver wrapper function.** \
If one has not been provided then write one. Its name should begin with the driver prefix, followed by transparent/opaque (depending on driver type), and end with the entry point name. It should have the same signature as the driver wrapper function. The purpose of the entry point function is to take arguments in PSA format for the implemented operation and return outputs/status codes in PSA format.
**4. Include the following in one of the driver header files:**
```
#if defined(DRIVER_PREFIX_ENABLED)
#ifndef PSA_CRYPTO_ACCELERATOR_DRIVER_PRESENT
#define PSA_CRYPTO_ACCELERATOR_DRIVER_PRESENT
#endif
```
**5. Conditionally include header files required by the driver**
Include any header files required by the driver in `psa_crypto_driver_wrappers.h`, placing the `#include` statements within an `#if defined` block which checks if the driver is available:
```
#if defined(DRIVER_PREFIX_ENABLED)
#include ...
#endif
```
**6. Modify the driver wrapper function** \
Each driver wrapper function contains a `switch` statement which checks the location of the key. If the key is stored in local storage, then operations are performed by a transparent driver. If it is stored elsewhere, then operations are performed by an opaque driver.
* **Transparent drivers:** Calls to drivers go under `case PSA_KEY_LOCATION_LOCAL_STORAGE`
<!-- the developer must manually edit the driver dispatch layer such that it first checks for the presence of the driver, and its compatibility with operation parameters (such as key type, algorithm type etc.). If the checks are passed, the driver's entry point function for that operation is called. The specification for the signature of entry point functions can be found [here](https://github.com/Mbed-TLS/mbedtls/blob/development/docs/proposed/psa-driver-interface.md#overview-of-driver-entry-points), but as a rule of thumb the signature for the driver entry point for an operation will be the same as the signature of its driver wrapper function. -->

12
include/mbedtls/mbedtls_config.h
View file

@ -3919,4 +3919,16 @@
*/
//#define MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED
/**
* Uncomment to enable p256-m, which implements ECC key generation, ECDH,
* and ECDSA for SECP256R1 curves. This driver is used as an example to
* document how a third-party driver or software accelerator can be integrated
* to work alongside Mbed TLS.
*
* \warning As of now, the built-in RNG for p256-m depends on rand(). This is
* fine for examples, but not in production.
* DO NOT ENABLE/USE THIS MACRO IN PRODUCTION BUILDS!
*/
//#define MBEDTLS_P256M_EXAMPLE_DRIVER_ENABLED
/** \} name SECTION: Module configuration options */

4
library/psa_crypto_driver_wrappers.h
View file

@ -24,6 +24,10 @@
#include "psa/crypto.h"
#include "psa/crypto_driver_common.h"
#if defined(MBEDTLS_P256M_EXAMPLE_DRIVER_ENABLED)
#include "../3rdparty/p256-m/p256-m_driver_entrypoints.h"
#endif /* MBEDTLS_P256M_EXAMPLE_DRIVER_ENABLED */
/*
* Initialization and termination functions
*/

1
scripts/config.py
View file

@ -216,6 +216,7 @@ EXCLUDE_FROM_FULL = frozenset([
'MBEDTLS_TEST_CONSTANT_FLOW_VALGRIND', # build dependency (valgrind headers)
'MBEDTLS_X509_REMOVE_INFO', # removes a feature
'MBEDTLS_SSL_RECORD_SIZE_LIMIT', # in development, currently breaks other tests
'MBEDTLS_P256M_EXAMPLE_DRIVER_ENABLED' # influences SECP256R1 KeyGen/ECDH/ECDSA
])
def is_seamless_alt(name):

72
scripts/data_files/driver_templates/psa_crypto_driver_wrappers.c.jinja
View file

@ -316,6 +316,26 @@ psa_status_t psa_driver_wrapper_sign_hash(
if( status != PSA_ERROR_NOT_SUPPORTED )
return( status );
#endif /* PSA_CRYPTO_DRIVER_TEST */
#if defined (MBEDTLS_P256M_EXAMPLE_DRIVER_ENABLED)
if( PSA_KEY_TYPE_IS_ECC( attributes->core.type ) &&
PSA_ALG_IS_ECDSA(alg) &&
!PSA_ALG_ECDSA_IS_DETERMINISTIC( alg ) &&
PSA_KEY_TYPE_ECC_GET_FAMILY(attributes->core.type) == PSA_ECC_FAMILY_SECP_R1 &&
attributes->core.bits == 256 )
{
status = p256m_transparent_sign_hash( attributes,
key_buffer,
key_buffer_size,
alg,
hash,
hash_length,
signature,
signature_size,
signature_length );
if( status != PSA_ERROR_NOT_SUPPORTED )
return( status );
}
#endif /* MBEDTLS_P256M_EXAMPLE_DRIVER_ENABLED */
#endif /* PSA_CRYPTO_ACCELERATOR_DRIVER_PRESENT */
/* Fell through, meaning no accelerator supports this operation */
return( psa_sign_hash_builtin( attributes,
@ -400,6 +420,25 @@ psa_status_t psa_driver_wrapper_verify_hash(
if( status != PSA_ERROR_NOT_SUPPORTED )
return( status );
#endif /* PSA_CRYPTO_DRIVER_TEST */
#if defined (MBEDTLS_P256M_EXAMPLE_DRIVER_ENABLED)
if( PSA_KEY_TYPE_IS_ECC( attributes->core.type ) &&
PSA_ALG_IS_ECDSA(alg) &&
!PSA_ALG_ECDSA_IS_DETERMINISTIC( alg ) &&
PSA_KEY_TYPE_ECC_GET_FAMILY(attributes->core.type) == PSA_ECC_FAMILY_SECP_R1 &&
attributes->core.bits == 256 )
{
status = p256m_transparent_verify_hash( attributes,
key_buffer,
key_buffer_size,
alg,
hash,
hash_length,
signature,
signature_length );
if( status != PSA_ERROR_NOT_SUPPORTED )
return( status );
}
#endif /* MBEDTLS_P256M_EXAMPLE_DRIVER_ENABLED */
#endif /* PSA_CRYPTO_ACCELERATOR_DRIVER_PRESENT */
return( psa_verify_hash_builtin( attributes,
@ -814,6 +853,20 @@ psa_status_t psa_driver_wrapper_generate_key(
if( status != PSA_ERROR_NOT_SUPPORTED )
break;
#endif /* PSA_CRYPTO_DRIVER_TEST */
#if defined(MBEDTLS_P256M_EXAMPLE_DRIVER_ENABLED)
if( PSA_KEY_TYPE_IS_ECC( attributes->core.type ) &&
attributes->core.type == PSA_KEY_TYPE_ECC_KEY_PAIR(PSA_ECC_FAMILY_SECP_R1) &&
attributes->core.bits == 256 )
{
status = p256m_transparent_generate_key( attributes,
key_buffer,
key_buffer_size,
key_buffer_length );
if( status != PSA_ERROR_NOT_SUPPORTED )
break;
}
#endif /* MBEDTLS_P256M_EXAMPLE_DRIVER_ENABLED */
}
#endif /* PSA_CRYPTO_ACCELERATOR_DRIVER_PRESENT */
@ -2752,6 +2805,25 @@ psa_status_t psa_driver_wrapper_key_agreement(
if( status != PSA_ERROR_NOT_SUPPORTED )
return( status );
#endif /* PSA_CRYPTO_DRIVER_TEST */
#if defined(MBEDTLS_P256M_EXAMPLE_DRIVER_ENABLED)
if( PSA_KEY_TYPE_IS_ECC( attributes->core.type ) &&
PSA_ALG_IS_ECDH(alg) &&
PSA_KEY_TYPE_ECC_GET_FAMILY(attributes->core.type) == PSA_ECC_FAMILY_SECP_R1 &&
attributes->core.bits == 256 )
{
status = p256m_transparent_key_agreement( attributes,
key_buffer,
key_buffer_size,
alg,
peer_key,
peer_key_length,
shared_secret,
shared_secret_size,
shared_secret_length );
if( status != PSA_ERROR_NOT_SUPPORTED)
return( status );
}
#endif /* MBEDTLS_P256M_EXAMPLE_DRIVER_ENABLED */
#endif /* PSA_CRYPTO_ACCELERATOR_DRIVER_PRESENT */
/* Software Fallback */