decrypt: Attempt to use a NewGCM() without specifying nonce and tag size before bailing.

[IsaacG]

The current code fails to decrypt messages from privatebin.net and private (unnamed) sites tested.

Using cipher.NewGCM(block) successfully decrypts messages from said sites. It may not always work, but it certainly works in more scenarios with more privatebin sites.

[gearnode]

Thanks for all your patches! For this one, could you provide more context on when this case would occur? Go versions prior to 1.23 should never reach this code path, so I’d like to better understand the scenario.

[IsaacG]

Go versions prior to 1.23 should never reach this code path, so I’d like to better understand the scenario.

My personal and work PC are both running go 1.24.5. Does that help? I'm not seeing a NewAGM() function in the cipher docs that takes a nonce and tag size.

[gearnode]

Thanks this issue was first addressed by the #24 and the final implementation is now merged 55770ce