(MFC) Determine if a Zip is Encrypted or Password-Protected

Determines whether or not a zip archive is AES encrypted or password-protected.

Chilkat C/C++ Library Downloads MS Visual C/C++ Libs

See Also: Using MFC CString in Chilkat

#include <CkZip.h>

void ChilkatSample(void)
    {
    CkString strOut;

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

    CkZip zip;

    // An encrypted or password-protected zip can be opened
    // without specifying the password.  However, the contents
    // of the files cannot be unzipped without providing the correct
    // password.

    bool success = zip.OpenZip("something.zip");
    if (success != true) {
        strOut.append(zip.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // If the zip is password-protected, meaning that it uses
    // the old (insecure) Zip 2.0 encryption, then the
    // PasswordProtect property will be true
    bool bPwdProt = zip.get_PasswordProtect();
    if (bPwdProt) {
        strOut.append("This zip is password-protected.");
        strOut.append("\r\n");
    }

    // If the zip is AES encrypted (WinZip compatible) then
    // the Encryption property will be equal to 4.
    int encValue = zip.get_Encryption();
    if (encValue == 4) {
        strOut.append("This zip is AES encrypted.");
        strOut.append("\r\n");
    }

    // If the Encryption property = 0, then the zip is NOT
    // strong encrypted, and is either password-protected or
    // entirely unencrypted, depending on the value of the
    // PasswordProtect property.

    zip.CloseZip();


    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }