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：3D打印的普及对公共安全构成重大风险，因为任何拥有互联网接入和普通打印机的个人都能生产无法追踪的枪支、钥匙、假冒产品等。为协助政府当局应对这些新型安全威胁，已有多种方法被提出用于为3D打印物品添加标识信息。这类信息（称为指纹）通过多种比特嵌入技术写入物体中，例如改变熔融热塑性塑料层的高度，以及沉积具有不同磁性的金属粉末。然而，这些技术在现实法医场景中的实用性受到该问题的对抗性本质的制约。也就是说，3D打印过程完全超出执法机构的控制范围；是攻击者控制打印的所有方面并持有打印物品。为应对这些威胁，执法机构可监管3D打印机的制造过程，在其中强制实施指纹嵌入方案，并在法医调查中收集被攻击者篡改的残骸（例如破碎的3D打印枪支碎片）。因此，设计即使在攻击者执行打印时也能提取指纹的指纹技术至关重要。为此，我们提出SIDE（安全信息嵌入与提取）框架，该框架通过同时提供安全信息嵌入与安全信息提取，应对3D打印中法医指纹识别的对抗性本质。