pfSense

cert_get_issuer() doesn't work properly when a certificate's issuer has several attributes of the same type.

e.g.
CN=Some Root CA,OU=Certificates Department,OU=(c) Copyright SomeCorp,O=SomeCorp,C=US

vs.
CN=Some Root CA,OU=(c) Copyright SomeCorp,O=SomeCorp,C=US

cert_get_issuer() doesn't properly handle the two OU attributes.

cert_get_subject() works correctly, so comparisons are broken. This breaks cert chaining, misidentifies some root certs, and other bad things.

Copying the logic from cert_get_subject() seems to fix it.

Example broken cert (thawte). Adding it as a CA identifies issuer as external, but it's a root certificate.
OU=(c) 2008 thawte, Inc. - For authorized use only,OU=Certification Services Division,O=thawte, Inc.,CN=thawte Primary Root CA - G3,C=US

-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Example good cert (geotrust). Correctly identified as self-signed CA.
OU=(c) 2008 GeoTrust Inc. - For authorized use only,O=GeoTrust Inc.,CN=GeoTrust Primary Certification Authority - G3,C=US

-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----