upload android base code part6

android/system/keymaster/symmetric_key.cpp

@@ -0,0 +1,141 @@
+/*
+ * Copyright 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "symmetric_key.h"
+
+#include <assert.h>
+
+#include <openssl/err.h>
+#include <openssl/rand.h>
+
+#include <keymaster/android_keymaster_utils.h>
+#include <keymaster/logger.h>
+#include <keymaster/keymaster_context.h>
+
+#include "aes_key.h"
+#include "hmac_key.h"
+#include "openssl_err.h"
+
+namespace keymaster {
+
+keymaster_error_t SymmetricKeyFactory::GenerateKey(const AuthorizationSet& key_description,
+                                                   KeymasterKeyBlob* key_blob,
+                                                   AuthorizationSet* hw_enforced,
+                                                   AuthorizationSet* sw_enforced) const {
+    if (!key_blob || !hw_enforced || !sw_enforced)
+        return KM_ERROR_OUTPUT_PARAMETER_NULL;
+
+    uint32_t key_size_bits;
+    if (!key_description.GetTagValue(TAG_KEY_SIZE, &key_size_bits) ||
+        !key_size_supported(key_size_bits))
+        return KM_ERROR_UNSUPPORTED_KEY_SIZE;
+
+    keymaster_error_t error = validate_algorithm_specific_new_key_params(key_description);
+    if (error != KM_ERROR_OK)
+        return error;
+
+    size_t key_data_size = key_size_bits / 8;
+    KeymasterKeyBlob key_material(key_data_size);
+    if (!key_material.key_material)
+        return KM_ERROR_MEMORY_ALLOCATION_FAILED;
+
+    error = context_->GenerateRandom(key_material.writable_data(), key_data_size);
+    if (error != KM_ERROR_OK) {
+        LOG_E("Error generating %d bit symmetric key", key_size_bits);
+        return error;
+    }
+
+    return context_->CreateKeyBlob(key_description, KM_ORIGIN_GENERATED, key_material, key_blob,
+                                   hw_enforced, sw_enforced);
+}
+
+keymaster_error_t SymmetricKeyFactory::ImportKey(const AuthorizationSet& key_description,
+                                                 keymaster_key_format_t input_key_material_format,
+                                                 const KeymasterKeyBlob& input_key_material,
+                                                 KeymasterKeyBlob* output_key_blob,
+                                                 AuthorizationSet* hw_enforced,
+                                                 AuthorizationSet* sw_enforced) const {
+    if (!output_key_blob || !hw_enforced || !sw_enforced)
+        return KM_ERROR_OUTPUT_PARAMETER_NULL;
+
+    AuthorizationSet authorizations(key_description);
+
+    uint32_t key_size_bits;
+    if (!authorizations.GetTagValue(TAG_KEY_SIZE, &key_size_bits)) {
+        // Default key size if not specified.
+        key_size_bits = input_key_material.key_material_size * 8;
+        authorizations.push_back(TAG_KEY_SIZE, key_size_bits);
+    }
+
+    keymaster_error_t error = validate_algorithm_specific_new_key_params(key_description);
+    if (error != KM_ERROR_OK)
+        return error;
+
+    if (!key_size_supported(key_size_bits))
+        return KM_ERROR_UNSUPPORTED_KEY_SIZE;
+
+    if (input_key_material_format != KM_KEY_FORMAT_RAW)
+        return KM_ERROR_UNSUPPORTED_KEY_FORMAT;
+
+    if (key_size_bits != input_key_material.key_material_size * 8) {
+        LOG_E("Expected %d-bit key data but got %d bits", key_size_bits,
+              input_key_material.key_material_size * 8);
+        return KM_ERROR_INVALID_KEY_BLOB;
+    }
+
+    return context_->CreateKeyBlob(authorizations, KM_ORIGIN_IMPORTED, input_key_material,
+                                   output_key_blob, hw_enforced, sw_enforced);
+}
+
+static const keymaster_key_format_t supported_import_formats[] = {KM_KEY_FORMAT_RAW};
+const keymaster_key_format_t*
+SymmetricKeyFactory::SupportedImportFormats(size_t* format_count) const {
+    *format_count = array_length(supported_import_formats);
+    return supported_import_formats;
+}
+
+SymmetricKey::SymmetricKey(const KeymasterKeyBlob& key_material,
+                           const AuthorizationSet& hw_enforced, const AuthorizationSet& sw_enforced,
+                           keymaster_error_t* error)
+    : Key(hw_enforced, sw_enforced, error) {
+    if (*error != KM_ERROR_OK)
+        return;
+
+    uint8_t* tmp = dup_buffer(key_material.key_material, key_material.key_material_size);
+    if (tmp) {
+        key_data_.reset(tmp);
+        key_data_size_ = key_material.key_material_size;
+        *error = KM_ERROR_OK;
+    } else {
+        *error = KM_ERROR_MEMORY_ALLOCATION_FAILED;
+    }
+}
+
+SymmetricKey::~SymmetricKey() {
+    memset_s(key_data_.get(), 0, key_data_size_);
+}
+
+keymaster_error_t SymmetricKey::key_material(UniquePtr<uint8_t[]>* key_material,
+                                             size_t* size) const {
+    *size = key_data_size_;
+    key_material->reset(new (std::nothrow) uint8_t[*size]);
+    if (!key_material->get())
+        return KM_ERROR_MEMORY_ALLOCATION_FAILED;
+    memcpy(key_material->get(), key_data_.get(), *size);
+    return KM_ERROR_OK;
+}
+
+}  // namespace keymaster