/// <summary>
/// Add editing protection to this document.
/// </summary>
/// <param name="er">The type of protection to add to this document.</param>
/// <example>
/// <code>
/// // Create a new document.
/// using (DocX document = DocX.Create(@"Test.docx"))
/// {
/// // Allow no editing, only the adding of comment.
/// document.AddProtection(EditRestrictions.comments);
///
/// // Save the document.
/// document.Save();
/// }
/// </code>
/// </example>
/// <seealso cref="RemoveProtection"/>
/// <seealso cref="GetProtectionType"/>
/// <seealso cref="isProtected"/>
public void AddProtection(EditRestrictions er)
{
// Call remove protection before adding a new protection element.
RemoveProtection();
if (er == EditRestrictions.none)
return;
XElement documentProtection = new XElement(XName.Get("documentProtection", DocX.w.NamespaceName));
documentProtection.Add(new XAttribute(XName.Get("edit", DocX.w.NamespaceName), er.ToString()));
documentProtection.Add(new XAttribute(XName.Get("enforcement", DocX.w.NamespaceName), "1"));
settings.Root.AddFirst(documentProtection);
}
public void AddProtection(EditRestrictions er, string strPassword)
{
// http://blogs.msdn.com/b/vsod/archive/2010/04/05/how-to-set-the-editing-restrictions-in-word-using-open-xml-sdk-2-0.aspx
// Call remove protection before adding a new protection element.
RemoveProtection();
if (er == EditRestrictions.none)
return;
XElement documentProtection = new XElement(XName.Get("documentProtection", w.NamespaceName));
documentProtection.Add(new XAttribute(XName.Get("edit", w.NamespaceName), er.ToString()));
documentProtection.Add(new XAttribute(XName.Get("enforcement", w.NamespaceName), "1"));
int[] InitialCodeArray = { 0xE1F0, 0x1D0F, 0xCC9C, 0x84C0, 0x110C, 0x0E10, 0xF1CE, 0x313E, 0x1872, 0xE139, 0xD40F, 0x84F9, 0x280C, 0xA96A, 0x4EC3 };
int[,] EncryptionMatrix = new int[15, 7]
{
/* char 1 */ {0xAEFC, 0x4DD9, 0x9BB2, 0x2745, 0x4E8A, 0x9D14, 0x2A09},
/* char 2 */ {0x7B61, 0xF6C2, 0xFDA5, 0xEB6B, 0xC6F7, 0x9DCF, 0x2BBF},
/* char 3 */ {0x4563, 0x8AC6, 0x05AD, 0x0B5A, 0x16B4, 0x2D68, 0x5AD0},
/* char 4 */ {0x0375, 0x06EA, 0x0DD4, 0x1BA8, 0x3750, 0x6EA0, 0xDD40},
/* char 5 */ {0xD849, 0xA0B3, 0x5147, 0xA28E, 0x553D, 0xAA7A, 0x44D5},
/* char 6 */ {0x6F45, 0xDE8A, 0xAD35, 0x4A4B, 0x9496, 0x390D, 0x721A},
/* char 7 */ {0xEB23, 0xC667, 0x9CEF, 0x29FF, 0x53FE, 0xA7FC, 0x5FD9},
/* char 8 */ {0x47D3, 0x8FA6, 0x0F6D, 0x1EDA, 0x3DB4, 0x7B68, 0xF6D0},
/* char 9 */ {0xB861, 0x60E3, 0xC1C6, 0x93AD, 0x377B, 0x6EF6, 0xDDEC},
/* char 10 */ {0x45A0, 0x8B40, 0x06A1, 0x0D42, 0x1A84, 0x3508, 0x6A10},
/* char 11 */ {0xAA51, 0x4483, 0x8906, 0x022D, 0x045A, 0x08B4, 0x1168},
/* char 12 */ {0x76B4, 0xED68, 0xCAF1, 0x85C3, 0x1BA7, 0x374E, 0x6E9C},
/* char 13 */ {0x3730, 0x6E60, 0xDCC0, 0xA9A1, 0x4363, 0x86C6, 0x1DAD},
/* char 14 */ {0x3331, 0x6662, 0xCCC4, 0x89A9, 0x0373, 0x06E6, 0x0DCC},
/* char 15 */ {0x1021, 0x2042, 0x4084, 0x8108, 0x1231, 0x2462, 0x48C4}
};
// Generate the Salt
byte[] arrSalt = new byte[16];
RandomNumberGenerator rand = new RNGCryptoServiceProvider();
rand.GetNonZeroBytes(arrSalt);
//Array to hold Key Values
byte[] generatedKey = new byte[4];
//Maximum length of the password is 15 chars.
int intMaxPasswordLength = 15;
if (!String.IsNullOrEmpty(strPassword))
{
strPassword = strPassword.Substring(0, Math.Min(strPassword.Length, intMaxPasswordLength));
byte[] arrByteChars = new byte[strPassword.Length];
for (int intLoop = 0; intLoop < strPassword.Length; intLoop++)
{
int intTemp = Convert.ToInt32(strPassword[intLoop]);
arrByteChars[intLoop] = Convert.ToByte(intTemp & 0x00FF);
if (arrByteChars[intLoop] == 0)
arrByteChars[intLoop] = Convert.ToByte((intTemp & 0xFF00) >> 8);
}
int intHighOrderWord = InitialCodeArray[arrByteChars.Length - 1];
for (int intLoop = 0; intLoop < arrByteChars.Length; intLoop++)
{
int tmp = intMaxPasswordLength - arrByteChars.Length + intLoop;
for (int intBit = 0; intBit < 7; intBit++)
{
if ((arrByteChars[intLoop] & (0x0001 << intBit)) != 0)
{
intHighOrderWord ^= EncryptionMatrix[tmp, intBit];
}
}
}
int intLowOrderWord = 0;
// For each character in the strPassword, going backwards
for (int intLoopChar = arrByteChars.Length - 1; intLoopChar >= 0; intLoopChar--)
{
intLowOrderWord = (((intLowOrderWord >> 14) & 0x0001) | ((intLowOrderWord << 1) & 0x7FFF)) ^ arrByteChars[intLoopChar];
}
intLowOrderWord = (((intLowOrderWord >> 14) & 0x0001) | ((intLowOrderWord << 1) & 0x7FFF)) ^ arrByteChars.Length ^ 0xCE4B;
// Combine the Low and High Order Word
int intCombinedkey = (intHighOrderWord << 16) + intLowOrderWord;
// The byte order of the result shall be reversed [Example: 0x64CEED7E becomes 7EEDCE64. end example],
// and that value shall be hashed as defined by the attribute values.
for (int intTemp = 0; intTemp < 4; intTemp++)
{
generatedKey[intTemp] = Convert.ToByte(((uint)(intCombinedkey & (0x000000FF << (intTemp * 8)))) >> (intTemp * 8));
}
}
StringBuilder sb = new StringBuilder();
for (int intTemp = 0; intTemp < 4; intTemp++)
{
sb.Append(Convert.ToString(generatedKey[intTemp], 16));
}
generatedKey = Encoding.Unicode.GetBytes(sb.ToString().ToUpper());
byte[] tmpArray1 = generatedKey;
byte[] tmpArray2 = arrSalt;
byte[] tempKey = new byte[tmpArray1.Length + tmpArray2.Length];
Buffer.BlockCopy(tmpArray2, 0, tempKey, 0, tmpArray2.Length);
Buffer.BlockCopy(tmpArray1, 0, tempKey, tmpArray2.Length, tmpArray1.Length);
generatedKey = tempKey;
int iterations = 100000;
HashAlgorithm sha1 = new SHA1Managed();
generatedKey = sha1.ComputeHash(generatedKey);
byte[] iterator = new byte[4];
for (int intTmp = 0; intTmp < iterations; intTmp++)
{
iterator[0] = Convert.ToByte((intTmp & 0x000000FF) >> 0);
iterator[1] = Convert.ToByte((intTmp & 0x0000FF00) >> 8);
iterator[2] = Convert.ToByte((intTmp & 0x00FF0000) >> 16);
iterator[3] = Convert.ToByte((intTmp & 0xFF000000) >> 24);
generatedKey = concatByteArrays(iterator, generatedKey);
generatedKey = sha1.ComputeHash(generatedKey);
}
documentProtection.Add(new XAttribute(XName.Get("cryptProviderType", w.NamespaceName), "rsaFull"));
documentProtection.Add(new XAttribute(XName.Get("cryptAlgorithmClass", w.NamespaceName), "hash"));
documentProtection.Add(new XAttribute(XName.Get("cryptAlgorithmType", w.NamespaceName), "typeAny"));
documentProtection.Add(new XAttribute(XName.Get("cryptAlgorithmSid", w.NamespaceName), "4")); // SHA1
documentProtection.Add(new XAttribute(XName.Get("cryptSpinCount", w.NamespaceName), iterations.ToString()));
documentProtection.Add(new XAttribute(XName.Get("hash", w.NamespaceName), Convert.ToBase64String(generatedKey)));
documentProtection.Add(new XAttribute(XName.Get("salt", w.NamespaceName), Convert.ToBase64String(arrSalt)));
settings.Root.AddFirst(documentProtection);
}
