The prevalence of 3D printing poses a significant risk to public safety, as any individual with internet access and a commodity printer is able to produce untraceable firearms, keys, counterfeit products, etc. To aid government authorities in combating these new security threats, several approaches have been taken to tag 3D-prints with identifying information. Known as fingerprints, this information is written into the object using various bit embedding techniques; examples include varying the height of the molten thermoplastic layers, and depositing metallic powder with different magnetic properties. Yet, the practicality of theses techniques in real-world forensic settings is hindered by the adversarial nature of this problem. That is, the 3D-printing process is out of reach of any law enforcement agencies; it is the adversary who controls all aspects of printing and possesses the printed object. To combat these threats, law enforcement agencies can regulate the manufacturing of 3D printers, on which they may enforce a fingerprinting scheme, and collect adversarially tampered remains (e.g., fragments of a broken 3D-printed firearm) during forensic investigation. Therefore, it is important to devise fingerprinting techniques so that the fingerprint could be extracted even if printing is carried out by the adversary. To this end, we present SIDE (Secure Information Embedding and Extraction), a fingerprinting framework that tackles the adversarial nature of forensic fingerprinting in 3D prints by offering both secure information embedding and secure information extraction.

翻译：三维打印技术的普及对公共安全构成了重大风险，任何能够访问互联网并拥有商用打印机的人均可制造出无法追踪的枪支、钥匙、假冒产品等。为协助政府当局应对这些新型安全威胁，研究人员已开发多种方法在三维打印品中嵌入识别信息（即指纹），通过不同的比特嵌入技术将信息写入物体中，例如改变熔融热塑性塑料层的厚度，或沉积具有不同磁性的金属粉末。然而，这些技术在真实法医场景中的实用性受到其对抗性本质的制约：执法机构无法介入三维打印过程，而由对手全权控制打印环节并持有打印成品。为应对这些威胁，执法机构可监管三维打印机的制造过程，在设备上强制执行指纹嵌入方案，并在法医调查中收集被对手篡改的残骸（如破碎三维打印枪支的碎片）。因此，设计能够在对手执行打印时仍可提取指纹的技术至关重要。为此，我们提出SIDE（安全信息嵌入与提取）框架，该框架通过提供安全的信息嵌入与提取机制，解决了三维打印法医指纹识别中的对抗性本质问题。