openssl

page type::reference thing type::command utility platform::Linux mode::command line interface

About
openssl is the command-line program for managing SSL data and certificates.

Examples

 * To check that a certificate file is valid, and see what it says (does not work with key files) - typical file extensions are .crt, .ca:
 * openssl x509 -text -in filename 
 * To verify how a web server is presenting its certificate over https:
 * openssl s_client -connect vbz.net:443
 * To generate a new private key:
 * openssl genrsa -des3 -out filename.key 4096
 * To remove the pass phrase from a private key:
 * openssl rsa -in oldfile.key -out newfile.key 
 * There is slightly more explanation here.

Links

 * openssl.org
 * s_client
 * examples