Refactor key creation to use a registry of key factories.

Change-Id: I6ebab7b44e4a5dbea282397ab8aca437e71bdca0

1 files changed, 64 insertions, 1 deletions

diff --git a/asymmetric_key.cpp b/asymmetric_key.cpp
index 064cd7e..65249fe 100644
--- a/asymmetric_key.cpp
+++ b/asymmetric_key.cpp
@@ -14,16 +14,79 @@
  * limitations under the License.
  */
 
+#include "asymmetric_key.h"
+
 #include <openssl/x509.h>
 
 #include <hardware/keymaster_defs.h>
 
-#include "asymmetric_key.h"
+#include "ecdsa_key.h"
 #include "openssl_utils.h"
+#include "rsa_key.h"
 #include "unencrypted_key_blob.h"
 
 namespace keymaster {
 
+struct PKCS8_PRIV_KEY_INFO_Delete {
+    void operator()(PKCS8_PRIV_KEY_INFO* p) const { PKCS8_PRIV_KEY_INFO_free(p); }
+};
+
+EVP_PKEY* AsymmetricKeyFactory::ExtractEvpKey(keymaster_key_format_t key_format,
+                                              keymaster_algorithm_t expected_algorithm,
+                                              const uint8_t* key_data, size_t key_data_length,
+                                              keymaster_error_t* error) {
+    *error = KM_ERROR_OK;
+
+    if (key_data == NULL || key_data_length <= 0) {
+        *error = KM_ERROR_INVALID_KEY_BLOB;
+        return NULL;
+    }
+
+    if (key_format != KM_KEY_FORMAT_PKCS8) {
+        *error = KM_ERROR_UNSUPPORTED_KEY_FORMAT;
+        return NULL;
+    }
+
+    UniquePtr<PKCS8_PRIV_KEY_INFO, PKCS8_PRIV_KEY_INFO_Delete> pkcs8(
+        d2i_PKCS8_PRIV_KEY_INFO(NULL, &key_data, key_data_length));
+    if (pkcs8.get() == NULL) {
+        *error = KM_ERROR_MEMORY_ALLOCATION_FAILED;
+        return NULL;
+    }
+
+    UniquePtr<EVP_PKEY, EVP_PKEY_Delete> pkey(EVP_PKCS82PKEY(pkcs8.get()));
+    if (pkey.get() == NULL || EVP_PKEY_type(pkey->type) != convert_to_evp(expected_algorithm)) {
+        *error = KM_ERROR_INVALID_KEY_BLOB;
+        return NULL;
+    }
+
+    return pkey.release();
+}
+
+static const keymaster_key_format_t supported_import_formats[] = {KM_KEY_FORMAT_PKCS8};
+const keymaster_key_format_t* AsymmetricKeyFactory::SupportedImportFormats(size_t* format_count) {
+    *format_count = array_length(supported_import_formats);
+    return supported_import_formats;
+}
+
+static const keymaster_key_format_t supported_export_formats[] = {KM_KEY_FORMAT_X509};
+const keymaster_key_format_t* AsymmetricKeyFactory::SupportedExportFormats(size_t* format_count) {
+    *format_count = array_length(supported_export_formats);
+    return supported_export_formats;
+}
+
+/* static */
+int AsymmetricKeyFactory::convert_to_evp(keymaster_algorithm_t algorithm) {
+    switch (algorithm) {
+    case KM_ALGORITHM_RSA:
+        return EVP_PKEY_RSA;
+    case KM_ALGORITHM_ECDSA:
+        return EVP_PKEY_EC;
+    default:
+        return -1;
+    };
+}
+
 keymaster_error_t AsymmetricKey::LoadKey(const UnencryptedKeyBlob& blob) {
     UniquePtr<EVP_PKEY, EVP_PKEY_Delete> evp_key(EVP_PKEY_new());
     if (evp_key.get() == NULL)