yuzu-emu/mbedtls
2
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

Introduce mbedtls_pk_get_psa_attributes

Browse source 
Follow the specification in https://github.com/Mbed-TLS/mbedtls/pull/8657
as of dd77343381, i.e.
dd77343381/docs/architecture/psa-migration/psa-legacy-bridges.md (api-to-create-a-psa-key-from-a-pk-context)

This commit introduces the function declaration, its documentation, the
definition without the interesting parts and a negative unit test function.
Subsequent commits will add RSA, ECC and PK_OPAQUE support.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
This commit is contained in:
Gilles Peskine 2024-01-18 14:11:26 +01:00
parent bc5d9165ae
commit 0b17255da1
4 changed files with 207 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

116
include/mbedtls/pk.h
View file

@ -28,7 +28,7 @@
#include "mbedtls/ecdsa.h"
#endif
#if defined(MBEDTLS_USE_PSA_CRYPTO)
#if defined(MBEDTLS_PSA_CRYPTO_CLIENT)
#include "psa/crypto.h"
#endif
@ -484,6 +484,120 @@ int mbedtls_pk_can_do_ext(const mbedtls_pk_context *ctx, psa_algorithm_t alg,
psa_key_usage_t usage);
#endif /* MBEDTLS_USE_PSA_CRYPTO */
#if defined(MBEDTLS_PSA_CRYPTO_CLIENT)
/**
* \brief Determine valid PSA attributes that can be used to
* import a key into PSA.
*
* The attributes determined by this function are suitable
* for calling mbedtls_pk_import_into_psa() to create
* a PSA key with the same key material.
*
* The typical flow of operations involving this function is
* ```
* psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
* int ret = mbedtls_pk_get_psa_attributes(pk, &attributes);
* if (ret != 0) ...; // error handling omitted
* // Tweak attributes if desired
* psa_key_id_t key_id = 0;
* ret = mbedtls_pk_import_into_psa(pk, &attributes, &key_id);
* if (ret != 0) ...; // error handling omitted
* ```
*
* \note This function does not support RSA-alt contexts
* (set up with mbedtls_pk_setup_rsa_alt()).
*
* \param[in] pk The PK context to use. It must have been set up.
* It can either contain a key pair or just a public key.
* \param usage A single `PSA_KEY_USAGE_xxx` flag among the following:
* - #PSA_KEY_USAGE_DECRYPT: \p pk must contain a
* key pair. The output \p attributes will contain a
* key pair type, and the usage policy will allow
* #PSA_KEY_USAGE_ENCRYPT as well as
* #PSA_KEY_USAGE_DECRYPT.
* - #PSA_KEY_USAGE_DERIVE: \p pk must contain a
* key pair. The output \p attributes will contain a
* key pair type.
* - #PSA_KEY_USAGE_ENCRYPT: The output
* \p attributes will contain a public key type.
* - #PSA_KEY_USAGE_SIGN_HASH: \p pk must contain a
* key pair. The output \p attributes will contain a
* key pair type, and the usage policy will allow
* #PSA_KEY_USAGE_VERIFY_HASH as well as
* #PSA_KEY_USAGE_SIGN_HASH.
* - #PSA_KEY_USAGE_SIGN_MESSAGE: \p pk must contain a
* key pair. The output \p attributes will contain a
* key pair type, and the usage policy will allow
* #PSA_KEY_USAGE_VERIFY_MESSAGE as well as
* #PSA_KEY_USAGE_SIGN_MESSAGE.
* - #PSA_KEY_USAGE_VERIFY_HASH: The output
* \p attributes will contain a public key type.
* - #PSA_KEY_USAGE_VERIFY_MESSAGE: The output
* \p attributes will contain a public key type.
* \param[out] attributes
* On success, valid attributes to import the key into PSA.
* - The lifetime and key identifier are unchanged. If the
* attribute structure was initialized or reset before
* calling this function, this will result in a volatile
* key. Call psa_set_key_identifier() before or after this
* function if you wish to create a persistent key. Call
* psa_set_key_lifetime() before or after this function if
* you wish to import the key in a secure element.
* - The key type and bit-size are determined by the contents
* of the PK context. If the PK context contains a key
* pair, the key type can be either a key pair type or
* the corresponding public key type, depending on
* \p usage. If the PK context contains a public key,
* the key type is a public key type.
* - The key's policy is determined by the key type and
* the \p usage parameter. The usage always allows
* \p usage, exporting and copying the key, and
* possibly other permissions as documented for the
* \p usage parameter.
* The permitted algorithm is determined as follows
* based on the #mbedtls_pk_type_t type of \p pk,
* the chosen \p usage and other factors:
* - #MBEDTLS_PK_RSA with whose underlying
* #mbedtls_rsa_context has the padding mode
* #MBEDTLS_RSA_PKCS_V15:
* #PSA_ALG_RSA_PKCS1V15_SIGN(#PSA_ALG_ANY_HASH)
* if \p usage is SIGN/VERIFY, and
* #PSA_ALG_RSA_PKCS1V15_CRYPT
* if \p usage is ENCRYPT/DECRYPT.
* - #MBEDTLS_PK_RSA with whose underlying
* #mbedtls_rsa_context has the padding mode
* #MBEDTLS_RSA_PKCS_V21 and the digest type
* corresponding to the PSA algorithm \c hash:
* #PSA_ALG_RSA_PSS_ANY_SALT(#PSA_ALG_ANY_HASH)
* if \p usage is SIGN/VERIFY, and
* #PSA_ALG_RSA_OAEP(\c hash)
* if \p usage is ENCRYPT/DECRYPT.
* - #MBEDTLS_PK_RSA_ALT: not supported.
* - #MBEDTLS_PK_ECDSA or #MBEDTLS_PK_ECKEY
* if \p usage is SIGN/VERIFY:
* #PSA_ALG_DETERMINISTIC_ECDSA(#PSA_ALG_ANY_HASH)
* if #MBEDTLS_ECDSA_DETERMINISTIC is enabled,
* otherwise #PSA_ALG_ECDSA(#PSA_ALG_ANY_HASH).
* - #MBEDTLS_PK_ECKEY_DH or #MBEDTLS_PK_ECKEY
* if \p usage is DERIVE:
* #PSA_ALG_ECDH.
* - #MBEDTLS_PK_OPAQUE: same as the algorithm policy
* set for the underlying PSA key, except that
* sign/decrypt flags are removed if the type is
* set to a public key type.
* Note that the enrollment algorithm set with
* psa_set_key_enrollment_algorithm() is not copied.
*
* \return 0 on success.
* #MBEDTLS_ERR_PK_TYPE_MISMATCH if \p pk does not contain
* a key of the type identified in \p attributes.
* Another error code on other failures.
*/
int mbedtls_pk_get_psa_attributes(const mbedtls_pk_context *pk,
psa_key_usage_t usage,
psa_key_attributes_t *attributes);
#endif /* MBEDTLS_PSA_CRYPTO_CLIENT */
/**
* \brief Verify signature (including padding if relevant).
*

26
library/pk.c
View file

@ -29,7 +29,7 @@
#include "mbedtls/ecdsa.h"
#endif
#if defined(MBEDTLS_USE_PSA_CRYPTO)
#if defined(MBEDTLS_PSA_CRYPTO_CLIENT)
#include "psa_util_internal.h"
#include "md_psa.h"
#endif
@ -378,6 +378,30 @@ int mbedtls_pk_can_do_ext(const mbedtls_pk_context *ctx, psa_algorithm_t alg,
}
#endif /* MBEDTLS_USE_PSA_CRYPTO */
#if defined(MBEDTLS_PSA_CRYPTO_CLIENT)
int mbedtls_pk_get_psa_attributes(const mbedtls_pk_context *pk,
psa_key_usage_t usage,
psa_key_attributes_t *attributes)
{
mbedtls_pk_type_t pk_type = mbedtls_pk_get_type(pk);
switch (pk_type) {
#if defined(MBEDTLS_PK_RSA_ALT_SUPPORT)
case MBEDTLS_PK_RSA_ALT:
return MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE;
#endif /* MBEDTLS_PK_RSA_ALT_SUPPORT */
default:
return MBEDTLS_ERR_PK_BAD_INPUT_DATA;
}
usage |= PSA_KEY_USAGE_EXPORT | PSA_KEY_USAGE_COPY;
psa_set_key_usage_flags(attributes, usage);
return 0;
}
#endif
/*
* Helper for mbedtls_pk_sign and mbedtls_pk_verify
*/

5
tests/suites/test_suite_pk.data
View file

@ -680,3 +680,8 @@ pk_psa_wrap_sign_ext:MBEDTLS_PK_RSA:2048:MBEDTLS_PK_RSA:MBEDTLS_MD_SHA512
PSA wrapped sign ext: RSA2048, PK_RSASSA_PSS, MD_SHA512
depends_on:MBEDTLS_PKCS1_V21:MBEDTLS_MD_CAN_SHA512:MBEDTLS_RSA_C
pk_psa_wrap_sign_ext:MBEDTLS_PK_RSA:2048:MBEDTLS_PK_RSASSA_PSS:MBEDTLS_MD_SHA512
PSA attributes for pk: NONE (bad)
pk_get_psa_attributes_fail:MBEDTLS_PK_NONE:0:PSA_KEY_USAGE_SIGN_MESSAGE:MBEDTLS_ERR_PK_BAD_INPUT_DATA
# There is a (negative) test for pk_type=MBEDTLS_PK_RSA_ALT in pk_rsa_alt().

62
tests/suites/test_suite_pk.function
View file

@ -162,6 +162,33 @@ size_t mbedtls_rsa_key_len_func(void *ctx)
}
#endif /* MBEDTLS_RSA_C */
#if defined(MBEDTLS_PSA_CRYPTO_C)
static int pk_setup_for_type(mbedtls_pk_type_t pk_type, int want_pair,
mbedtls_pk_context *pk, psa_key_type_t *psa_type)
{
int ok = 0;
if (pk_type == MBEDTLS_PK_NONE) {
return 1;
}
TEST_EQUAL(mbedtls_pk_setup(pk, mbedtls_pk_info_from_type(pk_type)), 0);
switch (pk_type) {
default:
TEST_FAIL("Unknown PK type in test data");
break;
}
if (!want_pair) {
*psa_type = PSA_KEY_TYPE_PUBLIC_KEY_OF_KEY_PAIR(*psa_type);
}
ok = 1;
exit:
return ok;
}
#endif
#if defined(MBEDTLS_USE_PSA_CRYPTO)
/*
@ -1263,6 +1290,14 @@ void pk_rsa_alt()
TEST_ASSERT(mbedtls_pk_get_type(&alt) == MBEDTLS_PK_RSA_ALT);
TEST_ASSERT(strcmp(mbedtls_pk_get_name(&alt), "RSA-alt") == 0);
#if defined(MBEDTLS_PSA_CRYPTO_C)
psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
TEST_EQUAL(mbedtls_pk_get_psa_attributes(&alt,
PSA_KEY_USAGE_ENCRYPT,
&attributes),
MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE);
#endif /* MBEDTLS_PSA_CRYPTO_C */
/* Test signature */
#if SIZE_MAX > UINT_MAX
TEST_ASSERT(mbedtls_pk_sign(&alt, MBEDTLS_MD_NONE, hash, SIZE_MAX,
@ -1569,3 +1604,30 @@ exit:
PSA_DONE();
}
/* END_CASE */
/* BEGIN_CASE depends_on:MBEDTLS_PSA_CRYPTO_C */
void pk_get_psa_attributes_fail(int pk_type, int from_pair,
int usage_arg,
int expected_ret)
{
mbedtls_pk_context pk;
mbedtls_pk_init(&pk);
psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
psa_key_usage_t usage = usage_arg;
MD_OR_USE_PSA_INIT();
psa_key_type_t expected_psa_type;
if (!pk_setup_for_type(pk_type, from_pair, &pk, &expected_psa_type)) {
goto exit;
}
TEST_EQUAL(mbedtls_pk_get_psa_attributes(&pk, usage, &attributes),
expected_ret);
exit:
mbedtls_pk_free(&pk);
psa_reset_key_attributes(&attributes);
MD_OR_USE_PSA_DONE();
}
/* END_CASE */