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max passphrase lengths
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  1. pinentry (tried with the curses version) should give better information about the maximum passphrase lengths.

It seems 255 characters still work while 256 don't, but the program only says it would be too long.
For even longer passphrases, the program simply aborts without any (end-user) useful message, merely saying:

gpg: problem with the agent: No data callback in IPC
gpg: error creating passphrase: Operation cancelled

It would be nice if, in both cases, it could tell the maximum length, and in the latter, also why it fails.

Ideally it should also have the same maximums than what one can have with --passphrase-fd or --passphrase.

  1. However, when using --passphrase-fd or --passphrase no such limits seem to exist (or they're much larger).

The manpage should tell whether there is a maxmium and if so which. And also what happens if the given passphrase is longer (error? extra characters ignored?).


PS: Oh any I'm not actually going to use such long passphrases. I was just using the output of the argon2(-tool) with varying lengths for it's -l parameter and noted that with larger sizes, pinentry causes troubles.

Event Timeline

werner triaged this task as Normal priority.Tue, Jul 26, 10:59 AM
werner edited projects, added Documentation, gnupg; removed Bug Report.