Delphi OpenSSL Library

A Delphi wrapper for OpenSSL, providing high-level object-oriented interfaces for cryptographic operations. This library simplifies the use of OpenSSL's powerful encryption capabilities in Delphi applications, offering easy-to-use classes for RSA encryption, symmetric ciphers, digital signatures, and certificate handling.

Features

• Encrypt/Decrypt using RSA algorithm
• Symmetric cipher routines
• Base64 encoding e decoding
• Basic PAM support
• Generation of pseudo-random bit strings
• Basic SMIME support
• Generate RSA KeyPairs in PKCS PEM format
• Generate self-signed X.509 certificates and Certificate Signing Requests (CSR)

Usage

Encrypt with the public key inside X509 certificate

Command line:

OpenSSL rsautl -encrypt -certin -inkey publiccert.cer -in test.txt -out test.txt.cry

Source code:

var
  RSAUtil :TRSAUtil;
  Cerificate :TX509Cerificate;
begin
  RSAUtil := TRSAUtil.Create;
  try
    Cerificate := TX509Cerificate.Create;
    try
      Cerificate.LoadFromFile('publiccert.cer');
      RSAUtil.PublicKey.LoadFromCertificate(Cerificate);
      RSAUtil.PublicEncrypt('test.txt', 'test.txt.cry');
    finally
      Cerificate.Free;
    end;
  finally
    RSAUtil.Free;
  end;
end;

Encrypt with the public key in PEM format

Command line:

OpenSSL rsautl -encrypt -pubin -inkey publickey.pem -in test.txt -out test.txt.cry

Source code:

var
  RSAUtil :TRSAUtil;
begin
  RSAUtil := TRSAUtil.Create;
  try
    RSAUtil.PublicKey.LoadFromFile('publickey.pem');
    RSAUtil.PublicEncrypt('test.txt', 'test.txt.cry');
  finally
    RSAUtil.Free;
  end;
end;

Decrypt with the private key in PEM format

Command line:

OpenSSL rsautl -decrypt -inkey privatekey.pem -in test.txt.cry -out test.txt

Source code:

var
  RSAUtil :TRSAUtil;
begin
  RSAUtil := TRSAUtil.Create;
  try
    RSAUtil.PrivateKey.OnNeedPassphrase := PassphraseReader;
    RSAUtil.PrivateKey.LoadFromFile('privatekey.pem');
    RSAUtil.PrivateDecrypt('test.txt.cry', 'test.txt');
  finally
    RSAUtil.Free;
  end;
end;

Encrypt with AES256

Command line:

OpenSSL enc -base64 -aes256 -in text.plain -out text.aes256 -k secure

Source code:

var
  EncUtil :TEncUtil;
begin
  EncUtil := TEncUtil.Create;
  try
    EncUtil.UseBase64 := True;
    EncUtil.Passphrase := 'secure';
    EncUtil.Cipher := 'AES-256';
    EncUtil.Encrypt('text.plain', 'text.aes256');
  finally
    EncUtil.Free;
  end;
end;

Generate a self-signed certificate

Command line:

OpenSSL req -x509 -newkey rsa:2048 -keyout key.pem -out cert.pem -days 365 -nodes

Source code:

var
  ReqUtil: TReqUtil;
begin
  ReqUtil := TReqUtil.Create;
  try
    ReqUtil.GenerateSelfSignedCertificate('CN=localhost,O=MyCompany,C=IT', 365, 2048);
    ReqUtil.SaveCertificateToFile('cert.pem');
    ReqUtil.SavePrivateKeyToFile('key.pem');
  finally
    ReqUtil.Free;
  end;
end;

Generate a Certificate Signing Request (CSR)

Command line:

OpenSSL req -new -newkey rsa:2048 -keyout key.pem -out request.csr -nodes

Source code:

var
  ReqUtil: TReqUtil;
begin
  ReqUtil := TReqUtil.Create;
  try
    ReqUtil.GenerateCSR('CN=example.com,O=MyCompany,C=IT', 2048);
    ReqUtil.SaveCSRToFile('request.csr');
    ReqUtil.SavePrivateKeyToFile('key.pem');
  finally
    ReqUtil.Free;
  end;
end;

Todo

• Symmetric cryptography (partially done)
• compute hash functions
• Sign e verify
• RSA data management
• Data managing for X509
• Manage information according to the PKCS #12 standard

Prerequisite

Installing OpenSSL

If your application requires OpenSSL support, you must have the necessary library files in your file system before deploying your application.

Platform	Download Required	File Names	Static/Dynamic Linking
Windows (32-bit and 64-bit)	Yes	libeay32.dll and ssleay32.dll	Dynamic
iOS Device	Yes	libcrypto.a and libssl.a	Static
Android Device	No		Dynamic

Review the requirements below depending on the platform that you are using:

32-bit and 64-bit Windows

To install OpenSSL on 32-bit or 64-bit Windows, you need to copy the libeay32.dll and ssleay32.dll dynamic library files to your file system; you can download them from one of these locations:

• Option 1 - Download the OpenSSL installer files and install them.
• Option 2 - Download the OpenSSL compressed library files and copy the libeay32.dll and ssleay32.dll files to your system path.

If you go for Option 2 and decide to copy libeay32.dll and ssleay32.dll files to your system path, ensure you copy them to the right location:

• 32-bit Windows: You must copy the libeay32.dll and ssleay32.dll 32-bit files to your Windows system folder (System32 folder).
• 64-bit Windows: You must copy the libeay32.dll and ssleay32.dll 64-bit files to your Windows system folder for 64-bit files (System32) and the libeay32.dll and ssleay32.dll 32-bit files to your Windows 32-bit files folder (SysWOW64 folder).

So when working with a 64-bit Windows, remember:

• System32 folder is for 64-bit files only.
• SysWOW64 folder is for 32-bit files only.

Installation

• Add the source path "Source" to your Delphi project path
• Run the demo and follow the tutorial