Administer keychains, keys, certificates and the Security framework. More information: https://ss64.com/osx/security.html.
security list-keychains
security delete-keychain {{path/to/file.keychain}}
security create-keychain -p {{password}} {{path/to/file.keychain}}
security set-identity-preference -s {{URL|hostname|service}} -c "{{common_name}}" {{path/to/file.keychain}}
security add-certificates -k {{keychain.name}} {{path/to/cert.pem}}
security add-trusted-cert -k {{path/to/user-keychain.keychain-db}} {{path/to/ca-cert.pem}}
security remove-trusted-cert {{path/to/ca-cert.pem}}