function __fish_openssl_subcommand_options --description "Print options for openssl subcommand"
    set -l cmd (commandline -poc)
    openssl list -options $cmd[2] | string replace -r -- '^(\S*)\s*.*' '-$1'
end

complete -c openssl -n '__fish_use_subcommand' -x -a "(openssl list -1 -commands -cipher-commands -digest-commands)"
complete -c openssl -n 'not __fish_use_subcommand && string match -qr -- "^-" (commandline -ct)' -a "(__fish_openssl_subcommand_options)"