google-nomulus/java/google/registry/rde/RydeFileEncoding.java
guyben 9f83544113 Move the RDE PGP file encoding to a dedicated file
The "file encoding" saves the file + metadata (filename and modification) in a "blob" format that PGP knows how to read.

Merges the file-encoder creation between RyDE and Ghostryde.

The new file - RydeFileEncoding.java - is a merge of the removed functions in
Ghostryde.java and the RydePgpFileOutputStream.java.

This is one of a series of CLs - each merging a single "part" of the encoding.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=205295756
2018-08-10 13:44:25 -04:00

107 lines
3.9 KiB
Java

// Copyright 2018 The Nomulus Authors. All Rights Reserved.
//
// 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.
package google.registry.rde;
import static org.bouncycastle.openpgp.PGPLiteralData.BINARY;
import static org.joda.time.DateTimeZone.UTC;
import google.registry.util.ImprovedInputStream;
import google.registry.util.ImprovedOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import javax.annotation.CheckReturnValue;
import javax.annotation.WillNotClose;
import org.bouncycastle.openpgp.PGPLiteralData;
import org.bouncycastle.openpgp.PGPLiteralDataGenerator;
import org.joda.time.DateTime;
/**
* Input/Output stream for reading/writing PGP literal data layer.
*
* <p>OpenPGP messages are like an onion; there can be many layers like compression and encryption.
* It's important to wrap out plaintext in a literal data layer such as this so the code that's
* unwrapping the onion knows when to stop.
*
* <p>According to escrow spec, the PGP message should contain a single tar file.
*/
final class RydeFileEncoding {
private static final int BUFFER_SIZE = 64 * 1024;
/**
* Creates an OutputStream that encodes the data as a PGP file blob.
*
* <p>TODO(b/110465964): document where the input comes from / output goes to. Something like
* documenting that os is the result of openCompressor and the result is used for the actual file
* data (Ghostryde) / goes in to openTarEncoder (RyDE).
*
* @param os where to write the file blob. Is not closed by this object.
* @param filename the filename to set in the file's metadata.
* @param modified the modification time to set in the file's metadata.
*/
@CheckReturnValue
static ImprovedOutputStream openPgpFileWriter(
@WillNotClose OutputStream os, String filename, DateTime modified) {
try {
return new ImprovedOutputStream(
"PgpFileWriter",
new PGPLiteralDataGenerator()
.open(os, BINARY, filename, modified.toDate(), new byte[BUFFER_SIZE]));
} catch (IOException e) {
throw new RuntimeException(e);
}
}
/** Input stream to a PGP file's data that also holds the file's metadata. */
static class PgpFileInputStream extends ImprovedInputStream {
private final String filename;
private final DateTime modified;
private PgpFileInputStream(PGPLiteralData literal) {
super("PgpFileReader", literal.getDataStream());
filename = literal.getFileName();
modified = new DateTime(literal.getModificationTime(), UTC);
}
/** Returns the name of the original file. */
String getFilename() {
return filename;
}
/** Returns the time this file was created or modified. */
DateTime getModified() {
return modified;
}
}
/**
* Opens an InputStream to a PGP file blob's data.
*
* <p>The result includes the file's metadata - the file name and modification time.
*
* <p>TODO(b/110465964): document where the input comes from / output goes to. Something like
* documenting that input is the result of openDecompressor and the result is the final file
* (Ghostryde) / goes into openTarDecoder (RyDE).
*
* @param input from where to read the file blob.
*/
@CheckReturnValue
static PgpFileInputStream openPgpFileReader(@WillNotClose InputStream input) {
return new PgpFileInputStream(PgpUtils.readSinglePgpObject(input, PGPLiteralData.class));
}
private RydeFileEncoding() {}
}