Quotable signature schemes are digital signature schemes with the additional property that from the signature for a message, any party can extract signatures for (allowable) quotes from the message, without knowing the secret key or interacting with the signer of the original message. Crucially, the extracted signatures are still signed with the original secret key. We define a notion of security for quotable signature schemes and construct a concrete example of a quotable signature scheme, using Merkle trees and classical digital signature schemes. The scheme is shown to be secure, with respect to the aforementioned notion of security. Additionally, we prove bounds on the complexity of the constructed scheme and provide algorithms for signing, quoting, and verifying. Finally, concrete use cases of quotable signatures are considered, using them to combat misinformation by bolstering authentic content on social media. We consider both how quotable signatures can be used, and why using them could help mitigate the effects of fake news.
翻译:引证签字办法是一种数字签字办法,其附加财产包括:从签字获得电文后,任何一方都可以从电文中提取(可变)报价的签名,而不知道秘密密钥,或与原始电文的签名人进行互动。关键是,所提取的签名仍然与原始秘密密钥签字。我们界定了可配额签字办法的安全概念,并用Merkle树和传统数字签名办法构建了一个可配额签字办法的具体范例。在前述安全概念方面,该计划被证明是安全的。此外,我们证明对所建办法的复杂性有一定的界限,并提供签名、引用和核实的算法。最后,考虑了可配额签字的具体使用案例,通过在社交媒体上支持真实内容来打击错误信息。我们考虑了如何使用可配额签字,以及为什么使用这些签名可以帮助减轻虚假新闻的影响。</s>