1 files changed, 80 insertions, 0 deletions
diff --git a/cmds/incidentd/src/cipher/ProtoEncryption.h b/cmds/incidentd/src/cipher/ProtoEncryption.h
new file mode 100644
index 000000000000..5b72ca88ec64
--- /dev/null
+++ b/cmds/incidentd/src/cipher/ProtoEncryption.h
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+#pragma once
+
+#include <android/util/ProtoOutputStream.h>
+#include <android/util/ProtoReader.h>
+#include <frameworks/base/cmds/incidentd/src/cipher/cipher_blocks.pb.h>
+
+#include "FdBuffer.h"
+
+namespace android {
+namespace os {
+namespace incidentd {
+
+// PlainText IncidentReport format
+// [section1_header(id, size, type)][section1_data] ...
+
+// Let's say section1 needs encryption
+// After encryption, it becomes
+// [section1_header(id, encrypted_size, type)][[cipher_block][cipher_block][cipher_block]..]
+
+// When clients read the report, it's decrypted, and written in its original format
+
+/**
+ * Takes a ProtoReader, encrypts its whole content -- which is one section, and flush to
+ * a file descriptor.
+ * The underlying encryption is done using Keystore binder APIs. We encrypt the data
+ * in blocks, and write to the file in android.os.incidentd.CipherBlocks format.
+ */
+class ProtoEncryptor {
+public:
+    ProtoEncryptor(const sp<android::util::ProtoReader>& reader) : mReader(reader){};
+
+    // Encrypt the data from ProtoReader, and store in CipherBlocks format.
+    // return the size of CipherBlocks.
+    size_t encrypt();
+
+    status_t flush(int fd);
+
+private:
+    static const size_t sBlockSize = 8 * 1024;
+    const sp<android::util::ProtoReader> mReader;
+    android::util::ProtoOutputStream mOutputStream;
+};
+
+// Read data from ProtoReader, which is in CipherBlocks proto format. Parse and decrypt
+// block by block.
+class ProtoDecryptor {
+public:
+    ProtoDecryptor(const sp<android::util::ProtoReader>& reader, size_t size)
+        : mReader(reader), mTotalSize(size){};
+    status_t decryptAndFlush(FdBuffer* out);
+
+private:
+    const sp<android::util::ProtoReader> mReader;
+
+    // Total size in bytes we should read from ProtoReader.
+    const size_t mTotalSize;
+
+    // Read one cipher block from ProtoReader, instead of reading the whole content
+    // and parse to CipherBlocks which could be huge.
+    status_t readOneBlock(std::string* output);
+};
+
+}  // namespace incidentd
+}  // namespace os
+}  // namespace android