Linux-Apache-ModSSL

From DevRandom

KEYS

• Generate 1024 bit RSA key

openssl genrsa -out example.key 1024

• Generate 2048 bit triple DES private key which has to be encrypted with pass phrase

openssl genrsa -des3 -out example.key 2048

• Verify Key but don't print it to the screen

openssl rsa -in example.key -check -noout

• Verify Key and print it to the screen

openssl rsa -in example.key -check 

• Change/Remove pass phrase in the private key

openssl rsa -in example.key -out example.key.new

Certificates

• Generate a certificate signing request for an existing private key

openssl req -out example.csr -key example.key -new 

• Check a Certificate Signing Request

openssl req -text -noout -verify -in example.csr 

• Check a certificate

openssl x509 -in example.crt -text -noout 

• Check a certificate against a key. The modulus must match

openssl x509 -noout -modulus -in example.crt | openssl md5
openssl rsa -noout -modulus -in example.key | openssl md5

• Display the certificate fingerprints (MD5 and SHA1)

openssl x509 -noout -fingerprint -in example.crt
openssl x509 -noout -sha1 -fingerprint -in example.crt

• Who issued the cert

openssl x509 -noout -in example.pem -issuer

• Dates valid

openssl x509 -noout -in example.pem -dates

Other Commands

• List all available ciphers

openssl ciphers -v

• List only TLSv1 ciphers

openssl ciphers -v -tls1

• List only high encryption ciphers

openssl ciphers -v 'HIGH'

• Check if the server has the ciphers enabled

 openssl s_client -connect www.example.com:443 -cipher LOW
 openssl s_client -connect www.example.com:443 -cipher MEDIUM
 openssl s_client -connect www.example.com:443 -cipher HIGH