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Go

Duplicate openssl smime -decrypt -in some_file.dat.enc -binary -inform DER -inkey private.key -out some_file.dat

See more OpenSSL Examples

Demonstrates how to decrypt binary DER that was encrypted using the following openssl command:
openssl smime -encrypt -binary -aes-256-cbc -in some_file.dat -out some_file.dat.enc -outform DER cert.crt

Chilkat Go Downloads

Go
    success := false

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

    // Duplicates the following openssl command:
    // openssl smime -decrypt -in hello.txt.enc -binary -inform DER -inkey private.key -out hello.txt

    cert := chilkat.NewCert()
    success = cert.LoadFromFile("qa_data/openssl/EE.cer")
    if success == false {
        fmt.Println(cert.LastErrorText())
        cert.DisposeCert()
        return
    }

    bd := chilkat.NewBinData()
    success = bd.LoadFile("qa_data/openssl/EE.key")
    // Assuming success..

    privKey := chilkat.NewPrivateKey()
    success = privKey.LoadAnyFormat(bd,"")
    if success == false {
        fmt.Println(privKey.LastErrorText())
        cert.DisposeCert()
        bd.DisposeBinData()
        privKey.DisposePrivateKey()
        return
    }

    crypt := chilkat.NewCrypt2()
    success = crypt.SetDecryptCert2(cert,privKey)
    if success == false {
        fmt.Println(crypt.LastErrorText())
        cert.DisposeCert()
        bd.DisposeBinData()
        privKey.DisposePrivateKey()
        crypt.DisposeCrypt2()
        return
    }

    crypt.SetCryptAlgorithm("PKI")
    success = crypt.CkDecryptFile("qa_data/openssl/hello.txt.enc","qa_output/hello.txt")
    if success == false {
        fmt.Println(crypt.LastErrorText())
        cert.DisposeCert()
        bd.DisposeBinData()
        privKey.DisposePrivateKey()
        crypt.DisposeCrypt2()
        return
    }

    fmt.Println("Success.")

    cert.DisposeCert()
    bd.DisposeBinData()
    privKey.DisposePrivateKey()
    crypt.DisposeCrypt2()