1 /*
2 * Copyright 2022 The Netty Project
3 *
4 * The Netty Project licenses this file to you under the Apache License,
5 * version 2.0 (the "License"); you may not use this file except in compliance
6 * with the License. You may obtain a copy of the License at:
7 *
8 * https://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13 * License for the specific language governing permissions and limitations
14 * under the License.
15 */
16 package io.netty.handler.ssl;
17
18 import javax.net.ssl.SSLEngine;
19
20 /**
21 * Provides compression and decompression implementations for TLS Certificate Compression
22 * (<a href="https://tools.ietf.org/html/rfc8879">RFC 8879</a>).
23 */
24 public interface OpenSslCertificateCompressionAlgorithm {
25
26 /**
27 * Compress the given input with the specified algorithm and return the compressed bytes.
28 *
29 * @param engine the {@link SSLEngine}
30 * @param uncompressedCertificate the uncompressed certificate
31 * @return the compressed form of the certificate
32 * @throws Exception thrown if an error occurs while compressing
33 */
34 byte[] compress(SSLEngine engine, byte[] uncompressedCertificate) throws Exception;
35
36 /**
37 * Decompress the given input with the specified algorithm and return the decompressed bytes.
38 *
39 * <h3>Implementation
40 * <a href="https://tools.ietf.org/html/rfc8879#section-5">Security Considerations</a></h3>
41 * <p>Implementations SHOULD bound the memory usage when decompressing the CompressedCertificate message.</p>
42 * <p>
43 * Implementations MUST limit the size of the resulting decompressed chain to the specified {@code uncompressedLen},
44 * and they MUST abort the connection (throw an exception) if the size of the output of the decompression
45 * function exceeds that limit.
46 * </p>
47 *
48 * @param engine the {@link SSLEngine}
49 * @param uncompressedLen the expected length of the decompressed certificate that will be returned.
50 * @param compressedCertificate the compressed form of the certificate
51 * @return the decompressed form of the certificate
52 * @throws Exception thrown if an error occurs while decompressing or output size exceeds
53 * {@code uncompressedLen}
54 */
55 byte[] decompress(SSLEngine engine, int uncompressedLen, byte[] compressedCertificate) throws Exception;
56
57 /**
58 * Return the ID for the compression algorithm provided for by a given implementation.
59 *
60 * @return compression algorithm ID as specified by
61 * <a href="https://datatracker.ietf.org/doc/html/rfc8879">RFC8879</a>.
62 */
63 int algorithmId();
64 }