Add lint to check for multiple Reserved Policy Identifiers in Subordinate CA certificates#959
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christopher-henderson merged 37 commits intozmap:masterfrom Jun 15, 2025
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Added //nolint:all to comment block to avoid golangci-lint to complain about duplicate words in comment
Fixed import block
Fine to me. Co-authored-by: Christopher Henderson <[email protected]>
As per Chris Henderson's suggestion, to "improve readability".
As per Chris Henderson's suggestion.
Added CABFEV_Sec9_2_8_Date
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Great lint, thank you very much!
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Made suspicious by a recent incident (see https://bugzilla.mozilla.org/show_bug.cgi?id=1963663), I discovered that Zlint is lacking a uniqueness check for reserved policy identifiers within non-policy-restricted TLS SubCA certificates. It is in fact required by the CABF BRs that there is exactly one Reserved Policy Identifier in such CA certificates. I am therefore proposing this lint to fill the gap.
Although Ballot SC083 (implemented in BRs v2.1.3) made it absolutely clear, IMO it was already quite clear in BRs v2.0.0 that in a TLS SubCA certificate, if it is a policy restricted SubCA, "Regardless of the order of PolicyInformation values, the Certificate Policies extension MUST contain exactly one Reserved Certificate Policy Identifier" (quoted from the BRs, section 7.1.2.10.5). Therefore I set the EffectiveDate of this lint to the publication date of BRs v2.0.0.
This lint is configurable, thus allowing to safely distinguish a cross-certificate from a normal SubCA certificate. To signal this lint that the certificate under examination is a cross-certificate, pass to zlint a TOML file containing the following directive: