Reading ['encrypted_content'] is very slow while parsing a CMS envelope.

[abhinav-mishra-db]

I am parsing envelope encrypted audio files. I can quickly extract all parameters from the envelope object such as 'Key Encryption Key' and details of algorithms. But when extracting the symmetrically encrypted content ('encrypted_content']); the library takes unacceptable amount of time. e.g. for a 48 MB file this step takes approx. 2 minutes. Please suggest if I am doing anything wrong.

from asn1crypto import cms
# the slow step
# file_content is the bytes read.
cms.ContentInfo.load(file_content))['content']['encrypted_content_info']['encrypted_content'].native

[abhinavdrs]

help please :))

[wbond]

This is likely a result of overhead related to specific encoding decisions in the ASN.1 modules, combined with Python runtime performance characteristics.

The first step would be to profile and see where the time is being spent. Then we can determine if there is a bug to fix. If generally it is just the overhead of parsing binary data with Python, then the solution would potentially being some sort of optional, C-based parser.