Conversation
unsigned.Design removes the signature from an x509.Certificate and optionally replaces the signature algorithm with id-alg-unsigned (which makes it a true RFC 9925 unsigned certificate). This is useful for (a) generating MTC CA certificates and (b) reducing the size of lint certs that we store in the database. We don't want to replace the signature algorithm when storing lint certs, because we will later verify that all fields of a CA-signed precertificate match all fields of a lint final certificate, and swapping out signature algorithm would cause that check to break. These certificates can be parsed with `x509.ParseCertificate`, but of course they can't be verified.
aarongable
reviewed
Jul 29, 2026
beautifulentropy
requested changes
Jul 29, 2026
beautifulentropy
left a comment
beautifulentropy
left a comment
Member
There was a problem hiding this comment.
Looks good to me, just a couple nits.
ezekiel
approved these changes
Jul 30, 2026
ezekiel
left a comment
ezekiel
left a comment
Member
There was a problem hiding this comment.
This looks good - I'd go with more aggressive camel-casing in the exported .DeSign() and the feature bool UnSignLintCerts to make it clearer, but this is great as-is.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
4 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
unsigned.Design removes the signature from an x509.Certificate and optionally replaces the signature algorithm with id-alg-unsigned (which makes it a true RFC 9925 unsigned certificate).
This is useful for (a) generating MTC CA certificates and (b) reducing the size of lint certs that we store in the database.
We don't want to replace the signature algorithm when storing lint certs, because we will later verify that all fields of a CA-signed precertificate match all fields of a lint final certificate, and swapping out signature algorithm would cause that check to break.
These certificates can be parsed with
x509.ParseCertificate, but of course they can't be verified.(Bikeshedding very welcome on the package and function name! :D)