Function sequoia_openpgp::serialize::stream::padding::padme

pub fn padme(l: u64) -> u64

Padmé padding scheme.

Padmé leaks at most O(log log M) bits of information (with M being the maximum length of all messages) with an overhead of at most 12%, decreasing with message size.

This scheme leaks the same order of information as padding to the next power of two, while avoiding an overhead of up to 100%.

See Section 4 of Reducing Metadata Leakage from Encrypted Files and Communication with PURBs.

This function is meant to be used with Padder, see this example.