sun.security.ssl.AlpnExtension Maven / Gradle / Ivy
/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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package sun.security.ssl;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
final class AlpnExtension extends HelloExtension {
private static final String ALPN_TO_STRING_MSG =
"Application Layer Protocol Extension (ALPN) [0x%x/%d], " +
"client protocols: %s, selected protocol: %s, serialized " +
"data: %s";
static final int ID = 0x0010;
static final String NAME = "alpn";
String selectedProtocol;
String[] protocols;
byte[] outData;
AlpnExtension(ExtensionType extensionType) {
super(extensionType);
}
@Override
int length() {
// Length of the encoded extension, including the type and length fields
// - Two bytes for the extension type
// - Two bytes for the extension length
// - Two bytes for the name list length
// - length of the encoded protocols
return 6 + (short) outData.length;
}
@Override
void send(HandshakeOutStream handshakeOutStream) throws IOException {
handshakeOutStream.putInt16(ID);
handshakeOutStream.putInt16(outData.length + 2);
handshakeOutStream.putInt16(outData.length);
handshakeOutStream.write(outData);
}
@Override
public String toString() {
return String.format(ALPN_TO_STRING_MSG,
ID,
ID,
Arrays.toString(protocols),
selectedProtocol,
Debug.toString(outData));
}
static Builder builder() {
return new Builder();
}
static final class Builder {
private static final byte[] EMPTY_DATA = new byte[0];
private static final String[] NO_PROTOCOLS = new String[0];
private final AlpnExtension extension =
new AlpnExtension(ExtensionType.get(ID));
private HandshakeInStream in;
private int len;
Builder selectedProtocol(final String selectedProtocol) {
extension.selectedProtocol = selectedProtocol;
return this;
}
Builder protocols(final String[] protocols) {
extension.protocols = protocols;
return this;
}
Builder handshakeIn(final HandshakeInStream in, final int len) {
this.in = in;
// TODO len shouldn't be more than 2^16-1
this.len = len;
return this;
}
AlpnExtension build() throws IOException {
if (in != null) {
if (len > 0) {
final List list = new ArrayList<>(4);
int read = 0;
int newLen = in.getInt16();
while (read != newLen) {
// Draft-03, section 3 states:
// "Protocols are named by opaque, non-empty byte strings
// and the list of protocols is serialized as a concatenation
// of 8-bit length prefixed byte strings."
byte[] protocol = new byte[in.getInt8()];
in.read(protocol);
// the character encoding currently specified is UTF-8.
// TODO, make this lazy.
list.add(new String(protocol, "UTF-8"));
read += protocol.length + 1; // add one for the length prefix
}
extension.protocols = list.toArray(new String[list.size()]);
} else {
extension.protocols = NO_PROTOCOLS;
}
} else {
if (extension.selectedProtocol != null) {
final byte[] selectedProtocolBytes =
extension.selectedProtocol.getBytes("UTF-8");
final byte[] outBytes = new byte[selectedProtocolBytes.length + 1];
outBytes[0] = (byte) selectedProtocolBytes.length;
System.arraycopy(selectedProtocolBytes, 0,
outBytes, 1, selectedProtocolBytes.length);
extension.outData = outBytes;
} else {
if (extension.protocols.length == 0) {
extension.outData = EMPTY_DATA;
} else {
ByteArrayOutputStream out = new ByteArrayOutputStream();
for (String protocol : extension.protocols) {
if (protocol.length() > 0 && protocol.length() < 256) {
out.write((byte) protocol.length());
out.write(protocol.getBytes("UTF-8"));
} else {
// TODO add logging for the case where the
// protocol is an empty string or greater than 2^8-1.
}
}
// TODO len of outData shouldn't be more than 2^16-1
extension.outData = out.toByteArray();
}
}
}
return extension;
}
} // END Builder
} // END AlpnExtension