Ruby

Encrypt a File to a PKCS7 (CMS) Message

Shows how to encrypt a file into a PKCS7 encrypted message using the recipient's certificate. Public-key encryption requires no private key. However, the recipient's private key is necessary for decryption. Ruby

require 'chilkat'

success = false

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

crypt = Chilkat::CkCrypt2.new()

# Load the recipient's digital certificate. 
# We don't need the private key for encryption.
# Only the public key is needed (which is included in a certificate).
cert1 = Chilkat::CkCert.new()
success = cert1.LoadFromFile("qa_data/user1/cert_user1.pem")
# Assume success for the example, but make sure your application checks for success/failure...
crypt.SetEncryptCert(cert1)

# Indicate that we want PKI encryption (i.e. public-key infrastructure)
# to produce a CMS message (Cryptographic Message Syntax/PKCS7),
# that is be created with RSAES-OAEP padding, SHA256, and AES-256 for the
# bulk encryption.
crypt.put_CryptAlgorithm("pki")
crypt.put_Pkcs7CryptAlg("aes")
crypt.put_KeyLength(256)
crypt.put_OaepHash("sha256")
crypt.put_OaepPadding(true)

# Load the file to be encrypted...
fileData = Chilkat::CkBinData.new()
success = fileData.LoadFile("qa_data/jpg/penguins.jpg")
# Your app should check for success/failure..

# Encrypt the data.  The contents of the fileData object are replaced with the PKCS7 encrypted message.
success = crypt.EncryptBd(fileData)
if (success != true)
    print crypt.lastErrorText() + "\n";
    exit
end

# Save the PKCS7 encrypted message to a file..
success = fileData.WriteFile("qa_output/pkcs7_encrypted.p7")

print "OK." + "\n";