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Swift

openssl smime -encrypt -des3 -in <file> <pem file>

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OpenSSL SMIME encrypt file using PEM containing a certificate.

Chilkat Swift Downloads

Swift

func chilkatTest() {
    var success: Bool = false

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

    // Load the cert from a PEM file.

    let pem = CkoPem()!
    // Our particular PEM was not encrypted, so we pass an empty password.
    // Also, a private key is not needed for encryption.  The PEM used to test this example
    // happens to have a private key, but it's not actually used.
    success = pem.loadFile(path: "qa_data/openssl/rsaCertAndKey.pem", password: "")
    if success == false {
        print("\(pem.lastErrorText!)")
        return
    }

    if pem.numCerts.intValue == 0 {
        print("PEM does not contain any certificates.")
        return
    }

    var cert: CkoCert? = pem.getCert(index: 0)
    if pem.lastMethodSuccess == false {
        print("\(pem.lastErrorText!)")
        return
    }

    // -------------------------------------------------------------------------------------
    // Duplicate this OpenSSL command:   openssl smime -encrypt -des3 -in <file> <pem file>
    // -------------------------------------------------------------------------------------
    let crypt = CkoCrypt2()!
    success = crypt.setEncryptCert(cert: cert)
    if success == false {
        print("\(crypt.lastErrorText!)")
        cert = nil
        return
    }

    cert = nil

    crypt.cryptAlgorithm = "PKI"
    crypt.pkcs7CryptAlg = "3des"
    crypt.keyLength = 168

    // Load the file to be encrypted.
    let bd = CkoBinData()!
    success = bd.loadFile(path: "qa_data/openssl/hello.txt")
    if success == false {
        print("Failed to load the input file.")
        return
    }

    // Encrypt.
    success = crypt.encryptBd(bd: bd)
    if success == false {
        print("\(crypt.lastErrorText!)")
        return
    }

    // The openssl smime -encrypt command produces encrypte MIME such as this:

    // MIME-Version: 1.0
    // Content-Disposition: attachment; filename="smime.p7m"
    // Content-Type: application/x-pkcs7-mime; smime-type=enveloped-data; name="smime.p7m"
    // Content-Transfer-Encoding: base64
    // 
    // MIICzwYJKoZIhvcNAQcDoIICwDCCArwCAQAxggF8MIIBeAIBADBgMEoxCzAJBgNVBAYTAlVTMRYw
    // FAYDVQQKEw1MZXQncyBFbmNyeXB0MSMwIQYDVQQDExpMZXQncyBFbmNyeXB0IEF1dGhvcml0eSBY
    // MwISA9Nqgb1dH/XTDNeKzN1nR85iMA0GCSqGSIb3DQEBAQUABIIBAIQqPexjxWovgxwKV/r3HL/U
    // EP9Yozvz5hBeX5VvRZjKSi4FRw5wapElPK+4FB82hiAR9Mi3c16PvPSVkJv3l78Mv5uaaOs/OmUz
    // mIHFB6Z+l2E52BDmUVWJZTQ09vdWy6+NIRlg2R9Z1NkmZ4BZCJk6mHB/Yx03IaOxK8LnwieDMthM
    // SvxbhJnIOISN7k7ofs+/0vTXUpdQ+tlmwyVySMGQ6VMk+z4sqZJ2stacqCPtt/aiSwJ9p0OKmihf
    // 3KDJceXJtavIQeA97yz1LqPvle35mmd5sBhV9qQYdTV/KJ+YM5uEZ9BHYbvMJbADFHwKzhcEY3qA
    // 7T9acmEsb7NycOIwggE1BgkqhkiG9w0BBwEwFAYIKoZIhvcNAwcECERX/ZoHweSkgIIBEMmCMx49
    // zjVAnGqRaBbvzQT1hg0uQSxIJjxMxC+HSuM+eY9oSOsbrw4uIijHKH9NdOpeDsdRzg2z5EBM7AlP
    // Ht9DyPW5C2deV6RPX4F8gyExz+JUXrd+3Yb3AKTdpDkTWDmNCeO0r/YSqp518+mfU5hG8e336u51
    // HAM44FeknA8oThWsD/wUB1e8vzsatK4UXW/KSu/166V7z+VT86kd+IHa7t60U9Yp0ZXgcM5Pb5Ni
    // 69Qc5MKPzom2801H5UR/WjCgsxOIjOj49sKisjRy79skrJzxY5ZG05T0dKn6KC3TjRpIEEeOyhCd
    // Nm2Y7dcW8GLMepdhWay5vePmQxmvmhbAtBprIem14NcrYeG6D5wP

    // We have the body in bd
    // Construct the header and base64 body...
    let sbEncryptedMime = CkoStringBuilder()!

    sbEncryptedMime.appendLine(str: "MIME-Version: 1.0", crlf: true)
    sbEncryptedMime.appendLine(str: "Content-Disposition: attachment; filename=\"smime.p7m\"", crlf: true)
    sbEncryptedMime.appendLine(str: "Content-Type: application/x-pkcs7-mime; smime-type=enveloped-data; name=\"smime.p7m\"", crlf: true)
    sbEncryptedMime.appendLine(str: "Content-Transfer-Encoding: base64", crlf: true)
    sbEncryptedMime.appendLine(str: "", crlf: true)
    sbEncryptedMime.appendLine(str: bd.getEncoded(encoding: "base64_mime"), crlf: true)

    // Show the result.
    print("\(sbEncryptedMime.getAsString()!)")

    // or save to a file..
    success = sbEncryptedMime.writeFile(path: "qa_output/encryptedMime.txt", charset: "utf-8", emitBom: false)

}