/// <summary>Given two <see cref="SecureTextBox"/> controls containing passwords, checks that the passwords match
/// and are sufficiently strong. Message boxes will be displayed to the user if any problems are found with the
/// passwords. True is returned if the passwords should be used, and false if not.
/// </summary>
public static bool ValidateAndCheckPasswords(SecureTextBox pass1, SecureTextBox pass2)
{
if(!ValidatePasswords(pass1, pass2))
{
return false;
}
else if(pass1.TextLength == 0)
{
if(MessageBox.Show("You didn't enter a password! This is extremely insecure, as anybody can use your key. Are "+
"you sure you don't want a password?", "Password is blank!", MessageBoxButtons.YesNo,
MessageBoxIcon.Warning, MessageBoxDefaultButton.Button2) == DialogResult.No)
{
return false;
}
}
else if(pass1.GetPasswordStrength() < PasswordStrength.Moderate)
{
if(MessageBox.Show("You entered a weak password! This is not secure, as your password can be cracked in a "+
"relatively short period of time, allowing somebody access to your key. Are you sure you "+
"want a to use a weak password?", "Password is weak!", MessageBoxButtons.YesNo,
MessageBoxIcon.Warning, MessageBoxDefaultButton.Button2) == DialogResult.No)
{
return false;
}
}
return true;
}
/// <summary>Given two <see cref="SecureTextBox"/> controls containing passwords, checks that the passwords match.
/// Message boxes will be displayed to the user if any problems are found with the passwords. True is returned if
/// the passwords should be used, and false if not.
/// </summary>
public static bool ValidatePasswords(SecureTextBox pass1, SecureTextBox pass2)
{
if(!PGPUI.ArePasswordsEqual(pass1, pass2))
{
MessageBox.Show("The passwords you have entered do not match.", "Password mismatch", MessageBoxButtons.OK,
MessageBoxIcon.Error);
return false;
}
return true;
}
/// <summary>Given two <see cref="SecureTextBox"/> controls containing passwords, determines whether the passwords
/// in the two controls are equal, case-sensitively.
/// </summary>
public static bool ArePasswordsEqual(SecureTextBox pass1, SecureTextBox pass2)
{
bool passwordsMatch = true;
if(pass1.TextLength != pass2.TextLength)
{
passwordsMatch = false;
}
else
{
SecureString ss1 = null, ss2 = null;
IntPtr bstr1 = IntPtr.Zero, bstr2 = IntPtr.Zero;
try
{
ss1 = pass1.GetText();
ss2 = pass2.GetText();
bstr1 = Marshal.SecureStringToBSTR(ss1);
bstr2 = Marshal.SecureStringToBSTR(ss2);
unsafe
{
char* p1 = (char*)bstr1.ToPointer(), p2 = (char*)bstr2.ToPointer();
int length = ss1.Length;
for(int i=0; i<length; p1++, p2++, i++)
{
if(*p1 != *p2)
{
passwordsMatch = false;
break;
}
}
}
}
finally
{
Marshal.ZeroFreeBSTR(bstr1);
Marshal.ZeroFreeBSTR(bstr2);
ss1.Dispose();
ss2.Dispose();
}
}
return passwordsMatch;
}
