OpenSSL: Your Command Line Security Powerhouse

Master the art of secure communication with OpenSSL, a free and open-source toolkit. Explore its functionalities, installation process, and essential commands for managing certificates and encryption. Empower yourself to safeguard your data and online interactions.

What is OpenSSL?

OpenSSL is a powerful and versatile toolkit for implementing the Transport Layer Security (TLS) and Secure Sockets Layer (SSL) protocols. It also serves as a general-purpose cryptography library.

Download and Install OpenSSL

1. Download the installer from the provided link. For Windows users, visit wiki.openssl.org to select and download OpenSSL for your platform.
2. Run the installer and follow the installation wizard.
3. After installation, navigate to C:\OpenSSL-Win32\bin and double-click on openssl.exe to start OpenSSL. This will open a command prompt window.

OpenSSL Console

To interact with OpenSSL, use the command prompt. Here are some useful commands for converting certificate formats:

OpenSSL Commands for Certificate Conversion

To view all available commands, use:

  openssl help
              

To get help on a specific command, append -help:

  openssl pkcs12 -help
              

Key Commands for Converting Certificate Formats

• Convert PEM to DER Format:

  Syntax

  
    openssl x509 -outform der -in certificate.pem -out certificate.der
                        

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  Output

  
    # The output is the certificate in DER format.
                        

• Convert PEM to P7B Format:

  Syntax

  
    openssl crl2pkcs7 -nocrl -certfile certificate.cer -out certificate.p7b -certfile CACert.cer
                        

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  Output

  
    # The output is the certificate in P7B format.
                        

• Convert PEM to PFX Format:

  Syntax

  
    openssl pkcs12 -export -out certificate.pfx -inkey privateKey.key -in certificate.crt -certfile CACert.crt
                        

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  Output

  
    # The output is the certificate in PFX format.
                        

• Convert DER to PEM Format:

  Syntax

  
    openssl x509 -inform der -in certificate.cer -out certificate.pem
                        

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  Output

  
    # The output is the certificate in PEM format.
                        

• Convert P7B to PEM Format:

  Syntax

  
    openssl pkcs7 -print_certs -in certificate.p7b -out certificate.cer
                        

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  Output

  
    # The output is the certificate in PEM format.
                        

• Convert P7B to PFX Format:

  Syntax

  
    openssl pkcs7 -print_certs -in certificate.p7b -out certificate.cer
    openssl pkcs12 -export -in certificate.cer -inkey privateKey.key -out certificate.pfx -certfile CACert.cer
                        

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  Output

  
    # The output is the certificate in PFX format.
                        

• Convert PFX to PEM Format:

  Syntax

  
    openssl pkcs12 -in certificate.pfx -out certificate.cer -nodes
                        

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  Output

  
    # The output is the certificate in PEM format.