Allow CSR parsing to handle custom extensions

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@jean-airoldie is already working on this.

Since May 4, 2025.

  • #1 by @cpu — closed without merging
  • #164 by @cpu — closed without merging
  • #337 by @jean-airoldie — open

Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
35/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Stale
Tech stack
rust
Domain
security

Research direction

Start with CertificateSigningRequest::from_der and the custom_extensions field documentation linked in the issue, then trace where UnsupportedExtension is produced. Determine how unknown or custom extensions should be handled, and verify that a CSR containing a user-defined extension parses successfully without losing the extension data.

Written by the indexing model from the issue text.

Description

Hi,

Currently when using a user defined custom_extensions, this causes the CSR parsing to error out with UnsupportedExtension.

Would it be possible to allow CSR parsing of custom extensions, such as by providing a closure to handle unknown extensions?

Dominant language
Rust
Stars
516
Forks
160
No merged PRs in 30d

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