Recent advances of large language models in the field of Verilog generation have raised several ethical and security concerns, such as code copyright protection and dissemination of malicious code. Researchers have employed watermarking techniques to identify codes generated by large language models. However, the existing watermarking works fail to protect RTL code copyright due to the significant syntactic and semantic differences between RTL code and software code in languages such as Python. This paper proposes a hardware watermarking framework RTLMarker that embeds watermarks into RTL code and deeper into the synthesized netlist. We propose a set of rule-based Verilog code transformations , ensuring the watermarked RTL code's syntactic and semantic correctness. In addition, we consider an inherent tradeoff between watermark transparency and watermark effectiveness and jointly optimize them. The results demonstrate RTLMarker's superiority over the baseline in RTL code watermarking.

本文针对现有水印技术无法有效保护RTL代码版权的问题，提出了一种硬件水印框架RTLMarker，能够将水印嵌入RTL代码及其合成网表中。通过一系列基于规则的Verilog代码变换，确保水印的语法和语义正确性，同时优化水印透明度与有效性之间的权衡。研究结果表明，RTLMarker在RTL代码水印方面显著优于基线方法。

RTLMarker：通过硬件水印框架保护LLM生成的RTL版权