Practical quantum-computer resistant signature schemes

数字签名是实践中最流行的加密原语。它们保证了数据和文件的真实性，并允许确定数据的来源。在实际应用中，有三种数字签名方案：RSA、DSA和EC_DSA。如果所有这些方法都变得不安全，造成的损害将是巨大的。如果有可能构建具有足够容量的量子计算机，这种情况就会发生。因此，提供可替代的数字签名方案非常重要。在DFG项目“默克尔签名方案的可证明的安全、有效和长期安全变体”（GZ: BU 630/19-1）中，开发了基于哈希的签名方案XMSS [BDH11]及其扩展XMSSMT。该项目是本应用的基础。从理论和实践上验证了该方法的安全性和有效性。这个项目的目的是使XMSS和XMSSMT在实践中可用。这将与公司genua mbH （IT安全产品）合作，实现以下目标：1。开源实现，包括处理有状态性、参数选择和侧信道分析，2。标准化的准备,3。通信协议的集成。在实现第一个目标的背景下，需要解决几个开放的问题，这使得在开源库OpenSSL （C/ c++）和Bouncy Castle （JAVA）中进行集成成为可能，并且必须完成集成。第一个问题是如何处理两种方案的有状态性，这要求在任何时候都存在一致的状态，而不会过多地限制性能。目前使用的方案不需要这样做。第二个问题是针对不同平台的参数集的优化。即，与传统方案相比，该方案具有多个参数。第三个问题是侧信道分析，这是安全实现所必需的。标准化的准备工作包括一个RFC草案和一个ISO标准化草案。它还包括在相关标准化机构中介绍和讨论草案。作为第三个目标工作的一部分，开发了TLS、SSH和S/MIME的抗量子计算机变体。这是通过集成XMSS和XMSSMT实现的。它需要开发适当的格式和接口以及实现。当这三个目标实现后，XMSS和XMSSMT将可用于常见的应用程序。

Digital signatures are the most popular cryptographic primitives in practice. They guarantee the authenticity of data and documents and allow to determine the origin of data. In practice, three digital signature schemes are used: RSA, DSA, and EC_DSA. If all those methods become insecure, the resulting damage will be immense. This situation will occur if it is possible to construct quantum computers with sufficient capacity. It is therefore important to provide alternative digital signature schemes.In the DFG project "Provably secure, efficient and long-term secure variations of the Merkle signature scheme" (GZ: BU 630/19-1), which is the basis of the present application, the hash-based signature scheme XMSS [BDH11] and its extension XMSSMT were developed. Their security was proven, and their efficiency was demonstrated theoretically and practically.The aim of this project is to make XMSS and XMSSMT usable in practice. This will be done in cooperation with the company genua mbH (IT security products) by achieving the following goals:1. Open-source implementation, including handling the statefulness, parameter selection, and side channel analysis,2. Standardization preparation,3. Integration in communications protocols.In the context of achieving the first objective several open problems are to be solved, which enable the integration in the open source libraries OpenSSL (C/C++) and Bouncy Castle (JAVA), and the integration has to be done. The first problem is how to deal with the statefulness of both schemes, which requires that at any time a consistent state exists, without limiting the performance too much. This is not required by the schemes used today. The second problem is the optimization of parameter sets for different platforms. Namely, the schemes have a plurality of parameters, in contrast to traditional schemes. The third problem is the side-channel analysis, which is required for the implementation to be secure.The preparation of standardization includes a RFC draft and a draft for an ISO standardization. It also includes the presentation and discussion of the drafts in the relevant standardization bodies.As part of the work on the third goal, quantum-computer resistant variants of TLS, SSH and S/MIME are developed. This is achieved by integrating XMSS and XMSSMT. It requires the development of appropriate formats and interfaces as well as an implementation.When the three goals are achieved, XMSS and XMSSMT will be usable for common applications.