OpenSSL 1.0.2 (and thus BoringSSL) accepts keyUsage certSign or a
Netscape CA certificate-type in lieu of basicConstraints in an
intermediate certificate (unless X509_V_FLAG_X509_STRICT) is set.
Update-Note: This change tightens the code so that basicConstraints is required for intermediate certificates when verifying chains. This was previously only enabled if X509_V_FLAG_X509_STRICT was set, but that flag also has other effects.
Change-Id: I9e41f4c567084cf30ed08f015a744959982940af
Reviewed-on: https://boringssl-review.googlesource.com/30185
Reviewed-by: Matt Braithwaite <mab@google.com>
8bd1d07535