SocksAuthRequestDecoder Class — netty Architecture

Source Code

codec-socks/src/main/java/io/netty/handler/codec/socks/SocksAuthRequestDecoder.java lines 31–73

public class SocksAuthRequestDecoder extends ReplayingDecoder<State> {

    private String username;

    public SocksAuthRequestDecoder() {
        super(State.CHECK_PROTOCOL_VERSION);
    }

    @Override
    protected void decode(ChannelHandlerContext ctx, ByteBuf byteBuf, List<Object> out) throws Exception {
        switch (state()) {
            case CHECK_PROTOCOL_VERSION: {
                if (byteBuf.readByte() != SocksSubnegotiationVersion.AUTH_PASSWORD.byteValue()) {
                    out.add(SocksCommonUtils.UNKNOWN_SOCKS_REQUEST);
                    break;
                }
                checkpoint(State.READ_USERNAME);
            }
            case READ_USERNAME: {
                int fieldLength = byteBuf.readByte();
                username = byteBuf.readString(fieldLength, CharsetUtil.US_ASCII);
                checkpoint(State.READ_PASSWORD);
            }
            case READ_PASSWORD: {
                int fieldLength = byteBuf.readByte();
                String password = byteBuf.readString(fieldLength, CharsetUtil.US_ASCII);
                out.add(new SocksAuthRequest(username, password));
                break;
            }
            default: {
                throw new Error("Unexpected request decoder state: " + state());
            }
        }
        ctx.pipeline().remove(this);
    }

    @UnstableApi
    public enum State {
        CHECK_PROTOCOL_VERSION,
        READ_USERNAME,
        READ_PASSWORD
    }
}