encryption - PGP/GPG 使用不同的密钥大小进行签名和加密

Question

使用 gpg/pgp 加密文件时是否可能或兼容，我们的客户端使用 1024 位密钥（他们的私钥）对其进行签名，然后使用我们的 2048 位公共密钥对其进行加密？

这会导致任何问题吗？

谢谢，埃卡

Answer 1

Nope, no issues. The operations are completely separate. The signature is encrypting a hash of the message, and the encryption of the result operates on the message + hash combination as a single message. Nothing requires the key lengths to be related.

That said, 1024 bit keys are a bit short in the bits and long in the tooth. You should encourage them to upgrade to 4096 bit keys at their next opportunity.