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Swift

Duplicate openssl dgst -md5 -sign myKey.pem something.txt | openssl enc -base64 -A

See more RSA Examples

Demonstrates how to duplicate the creation of an RSA signature produced by this OpenSSL command:
openssl dgst -md5 -sign myKey.pem something.txt | openssl enc -base64 -A

Chilkat Swift Downloads

Swift

func chilkatTest() {
    var success: Bool = false

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

    let pkey = CkoPrivateKey()!

    // Load the private key from an RSA PEM file:
    success = pkey.loadPemFile(path: "myKey.pem")

    let rsa = CkoRsa()!

    // Import the private key into the RSA component:
    success = rsa.usePrivateKey(privKey: pkey)
    if success == false {
        print("\(rsa.lastErrorText!)")
        return
    }

    // OpenSSL uses BigEndian byte ordering:
    rsa.littleEndian = false

    // The resulting signature will be a Base64 string:
    rsa.encodingMode = "base64"

    // For simplicity, we're not loading
    // the data to be signed from a file.  We are instead simply
    // using a literal string value.  
    var strData: String? = "This is the text to be signed."

    // Hash the input using MD5, and then sign the hash:
    // Other valid hash algorithm choices are "md2" and "sha-1".
    var base64Sig: String? = rsa.signStringENC(str: strData, hashAlg: "md5")

    print("\(base64Sig!)")

    print("Success!")

}