In this post, you will find below some useful usage of the OpenSSL tool. This commands can be used on both Linux and Windows environment.

For the Windows OS, I have choosen to use the pre-compiled packages at conan.io (version 1.1.1d). Other downloads/versions are available here.

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Extract the public key

Extract the public key from a PFX (PKCS12) file. Here the option -clcerts is used to only output client certificates (not CA certificates).

openssl pkcs12 -in yourfile.pfx -clcerts -nokeys -out yourfile.pem

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Extract the private key

• Extract the private key from a PFX (PKCS12) file. With this method, the openssl tool will ask you first the password of the PFX file. Then, a second password will be asked to protect/encrypt the private key. You can choose at this step the password of your choice

openssl pkcs12 -in yourfile.pfx -nocerts -out yourfile.key

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Remove or change the private key password

• Remove the private key password. First, enter the current private key password. Then, just it enter when OpenSSL tool asks for a password. This method can also be used to change the private key password by a new one.

openssl rsa -in yourfile.key -out yourfile_without_pwd.key