openssl x509 -inform der -in xxx.der -text
openssl x509 -in xxx.pem -text
openssl rsa -in xxx.pem -text
openssl req -inform der -in xxx.der -text
openssl req -in xxx.pem -text
openssl crl -inform der -in xxx.der -text
openssl crl -in xxx.pem -text
openssl smime -encrypt -aes256 -in original.txt -out encrypted.txt smime.cer
openssl smime -decrypt -aes256 -in encrypted.txt -out original.txt -inkey smime.key -recip smime.cer
openssl aes-256-cbc -e -in original.txt -out encrypted.txt
openssl aes-256-cbc -d -in encrypted.txt -out original.txt
openssl x509 -in cert.pem -pubkey > publickey.pem
openssl rsautl -verify -in encrypted.dat -pubin -inkey publickey.pem