/// <exception cref="System.IO.IOException"/>
/// <exception cref="Org.BouncyCastle.Security.GeneralSecurityException"/>
internal static DERForRecipientParams CalculateDERForRecipientParams(byte[] @in)
{
String s = "1.2.840.113549.3.2";
DERForRecipientParams parameters = new DERForRecipientParams();
byte[] outp = new byte[100];
DerObjectIdentifier derob = new DerObjectIdentifier(s);
byte[] abyte0 = IVGenerator.GetIV(16); // keyp
IBufferedCipher cf = CipherUtilities.GetCipher(derob);
KeyParameter kp = new KeyParameter(abyte0);
byte[] iv = IVGenerator.GetIV(cf.GetBlockSize());
ParametersWithIV piv = new ParametersWithIV(kp, iv);
cf.Init(true, piv);
int len = cf.DoFinal(@in, outp, 0);
byte[] abyte1 = new byte[len];
Array.Copy(outp, 0, abyte1, 0, len);
Asn1EncodableVector ev = new Asn1EncodableVector();
ev.Add(new DerInteger(58));
ev.Add(new DerOctetString(iv));
DerSequence seq = new DerSequence(ev);
parameters.abyte0 = abyte0;
parameters.abyte1 = abyte1;
parameters.algorithmIdentifier = new AlgorithmIdentifier(derob, seq);
return(parameters);
}
public OutputStreamEncryption(Stream outc, byte[] key, int off, int len, int revision)
{
this.outc = outc;
aes = (revision == AES_128 || revision == AES_256);
if (aes)
{
byte[] iv = IVGenerator.GetIV();
byte[] nkey = new byte[len];
System.Array.Copy(key, off, nkey, 0, len);
cipher = new AESCipher(true, nkey, iv);
Write(iv, 0, iv.Length);
}
else
{
arcfour = new ARCFOUREncryption();
arcfour.PrepareARCFOURKey(key, off, len);
}
}
internal static DERForRecipientParams CalculateDERForRecipientParams(byte[] @in)
{
/*
* According to ISO 32000-2 (7.6.5.3 Public-key encryption algorithms) RC-2 algorithm is outdated
* and should be replaced with a safer one 256-bit AES-CBC:
* The algorithms that shall be used to encrypt the enveloped data in the CMS object are:
* - RC4 with key lengths up to 256-bits (deprecated);
* - DES, Triple DES, RC2 with key lengths up to 128 bits (deprecated);
* - 128-bit AES in Cipher Block Chaining (CBC) mode (deprecated);
* - 192-bit AES in CBC mode (deprecated);
* - 256-bit AES in CBC mode.
*/
String s = "1.2.840.113549.3.2";
DERForRecipientParams parameters = new DERForRecipientParams();
byte[] outp = new byte[100];
DerObjectIdentifier derob = new DerObjectIdentifier(s);
// keyp
byte[] abyte0 = IVGenerator.GetIV(16);
IBufferedCipher cf = CipherUtilities.GetCipher(derob);
KeyParameter kp = new KeyParameter(abyte0);
byte[] iv = IVGenerator.GetIV(cf.GetBlockSize());
ParametersWithIV piv = new ParametersWithIV(kp, iv);
cf.Init(true, piv);
int len = cf.DoFinal(@in, outp, 0);
byte[] abyte1 = new byte[len];
Array.Copy(outp, 0, abyte1, 0, len);
Asn1EncodableVector ev = new Asn1EncodableVector();
ev.Add(new DerInteger(58));
ev.Add(new DerOctetString(iv));
DerSequence seq = new DerSequence(ev);
parameters.abyte0 = abyte0;
parameters.abyte1 = abyte1;
parameters.algorithmIdentifier = new AlgorithmIdentifier(derob, seq);
return(parameters);
}
private Asn1Object CreateDERForRecipient(byte[] inp, X509Certificate cert)
{
String s = "1.2.840.113549.3.2";
byte[] outp = new byte[100];
DerObjectIdentifier derob = new DerObjectIdentifier(s);
byte[] keyp = IVGenerator.GetIV(16);
IBufferedCipher cf = CipherUtilities.GetCipher(derob);
KeyParameter kp = new KeyParameter(keyp);
byte[] iv = IVGenerator.GetIV(cf.GetBlockSize());
ParametersWithIV piv = new ParametersWithIV(kp, iv);
cf.Init(true, piv);
int len = cf.DoFinal(inp, outp, 0);
byte[] abyte1 = new byte[len];
System.Array.Copy(outp, 0, abyte1, 0, len);
DerOctetString deroctetstring = new DerOctetString(abyte1);
KeyTransRecipientInfo keytransrecipientinfo = ComputeRecipientInfo(cert, keyp);
DerSet derset = new DerSet(new RecipientInfo(keytransrecipientinfo));
Asn1EncodableVector ev = new Asn1EncodableVector();
ev.Add(new DerInteger(58));
ev.Add(new DerOctetString(iv));
DerSequence seq = new DerSequence(ev);
AlgorithmIdentifier algorithmidentifier = new AlgorithmIdentifier(derob, seq);
EncryptedContentInfo encryptedcontentinfo =
new EncryptedContentInfo(PkcsObjectIdentifiers.Data, algorithmidentifier, deroctetstring);
Asn1Set set = null;
EnvelopedData env = new EnvelopedData(null, derset, encryptedcontentinfo, set);
Org.BouncyCastle.Asn1.Cms.ContentInfo contentinfo =
new Org.BouncyCastle.Asn1.Cms.ContentInfo(PkcsObjectIdentifiers.EnvelopedData, env);
return(contentinfo.ToAsn1Object());
}
public PdfPublicKeySecurityHandler()
{
seed = IVGenerator.GetIV(SEED_LENGTH);
recipients = new List <PdfPublicKeyRecipient>();
}
private void InitKeyAndFillDictionary(PdfDictionary encryptionDictionary, byte[] userPassword, byte[] ownerPassword
, int permissions, bool encryptMetadata, bool embeddedFilesOnly)
{
ownerPassword = GenerateOwnerPasswordIfNullOrEmpty(ownerPassword);
permissions |= PERMS_MASK_1_FOR_REVISION_3_OR_GREATER;
permissions &= PERMS_MASK_2;
try {
byte[] userKey;
byte[] ownerKey;
byte[] ueKey;
byte[] oeKey;
byte[] aes256Perms;
if (userPassword == null)
{
userPassword = new byte[0];
}
else
{
if (userPassword.Length > 127)
{
userPassword = JavaUtil.ArraysCopyOf(userPassword, 127);
}
}
if (ownerPassword.Length > 127)
{
ownerPassword = JavaUtil.ArraysCopyOf(ownerPassword, 127);
}
// first 8 bytes are validation salt; second 8 bytes are key salt
byte[] userValAndKeySalt = IVGenerator.GetIV(16);
byte[] ownerValAndKeySalt = IVGenerator.GetIV(16);
nextObjectKey = IVGenerator.GetIV(32);
nextObjectKeySize = 32;
byte[] hash;
// Algorithm 8.1
hash = ComputeHash(userPassword, userValAndKeySalt, 0, 8);
userKey = JavaUtil.ArraysCopyOf(hash, 48);
Array.Copy(userValAndKeySalt, 0, userKey, 32, 16);
// Algorithm 8.2
hash = ComputeHash(userPassword, userValAndKeySalt, 8, 8);
AESCipherCBCnoPad ac = new AESCipherCBCnoPad(true, hash);
ueKey = ac.ProcessBlock(nextObjectKey, 0, nextObjectKey.Length);
// Algorithm 9.1
hash = ComputeHash(ownerPassword, ownerValAndKeySalt, 0, 8, userKey);
ownerKey = JavaUtil.ArraysCopyOf(hash, 48);
Array.Copy(ownerValAndKeySalt, 0, ownerKey, 32, 16);
// Algorithm 9.2
hash = ComputeHash(ownerPassword, ownerValAndKeySalt, 8, 8, userKey);
ac = new AESCipherCBCnoPad(true, hash);
oeKey = ac.ProcessBlock(nextObjectKey, 0, nextObjectKey.Length);
// Algorithm 10
byte[] permsp = IVGenerator.GetIV(16);
permsp[0] = (byte)permissions;
permsp[1] = (byte)(permissions >> 8);
permsp[2] = (byte)(permissions >> 16);
permsp[3] = (byte)(permissions >> 24);
permsp[4] = (byte)(255);
permsp[5] = (byte)(255);
permsp[6] = (byte)(255);
permsp[7] = (byte)(255);
permsp[8] = encryptMetadata ? (byte)'T' : (byte)'F';
permsp[9] = (byte)'a';
permsp[10] = (byte)'d';
permsp[11] = (byte)'b';
ac = new AESCipherCBCnoPad(true, nextObjectKey);
aes256Perms = ac.ProcessBlock(permsp, 0, permsp.Length);
this.permissions = permissions;
this.encryptMetadata = encryptMetadata;
SetStandardHandlerDicEntries(encryptionDictionary, userKey, ownerKey);
SetAES256DicEntries(encryptionDictionary, oeKey, ueKey, aes256Perms, encryptMetadata, embeddedFilesOnly);
}
catch (Exception ex) {
throw new PdfException(PdfException.PdfEncryption, ex);
}
}
// gets keylength and revision and uses revison to choose the initial values for permissions
virtual public void SetupAllKeys(byte[] userPassword, byte[] ownerPassword, int permissions)
{
if (ownerPassword == null || ownerPassword.Length == 0)
{
ownerPassword = DigestAlgorithms.Digest("MD5", CreateDocumentId());
}
md5.Reset();
permissions |= (int)((revision == STANDARD_ENCRYPTION_128 || revision == AES_128 || revision == AES_256) ? (uint)0xfffff0c0 : (uint)0xffffffc0);
permissions &= unchecked ((int)0xfffffffc);
this.permissions = permissions;
if (revision == AES_256)
{
if (userPassword == null)
{
userPassword = new byte[0];
}
documentID = CreateDocumentId();
byte[] uvs = IVGenerator.GetIV(8);
byte[] uks = IVGenerator.GetIV(8);
key = IVGenerator.GetIV(32);
// Algorithm 3.8.1
IDigest md = DigestUtilities.GetDigest("SHA-256");
md.BlockUpdate(userPassword, 0, Math.Min(userPassword.Length, 127));
md.BlockUpdate(uvs, 0, uvs.Length);
userKey = new byte[48];
md.DoFinal(userKey, 0);
System.Array.Copy(uvs, 0, userKey, 32, 8);
System.Array.Copy(uks, 0, userKey, 40, 8);
// Algorithm 3.8.2
md.BlockUpdate(userPassword, 0, Math.Min(userPassword.Length, 127));
md.BlockUpdate(uks, 0, uks.Length);
byte[] tempDigest = new byte[32];
md.DoFinal(tempDigest, 0);
AESCipherCBCnoPad ac = new AESCipherCBCnoPad(true, tempDigest);
ueKey = ac.ProcessBlock(key, 0, key.Length);
// Algorithm 3.9.1
byte[] ovs = IVGenerator.GetIV(8);
byte[] oks = IVGenerator.GetIV(8);
md.BlockUpdate(ownerPassword, 0, Math.Min(ownerPassword.Length, 127));
md.BlockUpdate(ovs, 0, ovs.Length);
md.BlockUpdate(userKey, 0, userKey.Length);
ownerKey = new byte[48];
md.DoFinal(ownerKey, 0);
System.Array.Copy(ovs, 0, ownerKey, 32, 8);
System.Array.Copy(oks, 0, ownerKey, 40, 8);
// Algorithm 3.9.2
md.BlockUpdate(ownerPassword, 0, Math.Min(ownerPassword.Length, 127));
md.BlockUpdate(oks, 0, oks.Length);
md.BlockUpdate(userKey, 0, userKey.Length);
md.DoFinal(tempDigest, 0);
ac = new AESCipherCBCnoPad(true, tempDigest);
oeKey = ac.ProcessBlock(key, 0, key.Length);
// Algorithm 3.10
byte[] permsp = IVGenerator.GetIV(16);
permsp[0] = (byte)permissions;
permsp[1] = (byte)(permissions >> 8);
permsp[2] = (byte)(permissions >> 16);
permsp[3] = (byte)(permissions >> 24);
permsp[4] = (byte)(255);
permsp[5] = (byte)(255);
permsp[6] = (byte)(255);
permsp[7] = (byte)(255);
permsp[8] = encryptMetadata ? (byte)'T' : (byte)'F';
permsp[9] = (byte)'a';
permsp[10] = (byte)'d';
permsp[11] = (byte)'b';
ac = new AESCipherCBCnoPad(true, key);
perms = ac.ProcessBlock(permsp, 0, permsp.Length);
}
else
{
//PDF refrence 3.5.2 Standard Security Handler, Algorithum 3.3-1
//If there is no owner password, use the user password instead.
byte[] userPad = PadPassword(userPassword);
byte[] ownerPad = PadPassword(ownerPassword);
this.ownerKey = ComputeOwnerKey(userPad, ownerPad);
documentID = CreateDocumentId();
SetupByUserPad(this.documentID, userPad, this.ownerKey, permissions);
}
}
internal static byte[] GenerateSeed(int seedLength)
{
return(IVGenerator.GetIV(seedLength));
}
private void InitKeyAndFillDictionary(PdfDictionary encryptionDictionary, byte[] userPassword, byte[] ownerPassword
, int permissions, bool encryptMetadata, bool embeddedFilesOnly)
{
ownerPassword = GenerateOwnerPasswordIfNullOrEmpty(ownerPassword);
permissions |= PERMS_MASK_1_FOR_REVISION_3_OR_GREATER;
permissions &= PERMS_MASK_2;
try {
byte[] userKey;
byte[] ownerKey;
byte[] ueKey;
byte[] oeKey;
byte[] aes256Perms;
if (userPassword == null)
{
userPassword = new byte[0];
}
byte[] uvs = IVGenerator.GetIV(8);
byte[] uks = IVGenerator.GetIV(8);
nextObjectKey = IVGenerator.GetIV(32);
nextObjectKeySize = 32;
// Algorithm 3.8.1
IDigest md = Org.BouncyCastle.Security.DigestUtilities.GetDigest("SHA-256");
md.Update(userPassword, 0, Math.Min(userPassword.Length, 127));
md.Update(uvs);
userKey = new byte[48];
md.Digest(userKey, 0, 32);
System.Array.Copy(uvs, 0, userKey, 32, 8);
System.Array.Copy(uks, 0, userKey, 40, 8);
// Algorithm 3.8.2
md.Update(userPassword, 0, Math.Min(userPassword.Length, 127));
md.Update(uks);
AESCipherCBCnoPad ac = new AESCipherCBCnoPad(true, md.Digest());
ueKey = ac.ProcessBlock(nextObjectKey, 0, nextObjectKey.Length);
// Algorithm 3.9.1
byte[] ovs = IVGenerator.GetIV(8);
byte[] oks = IVGenerator.GetIV(8);
md.Update(ownerPassword, 0, Math.Min(ownerPassword.Length, 127));
md.Update(ovs);
md.Update(userKey);
ownerKey = new byte[48];
md.Digest(ownerKey, 0, 32);
System.Array.Copy(ovs, 0, ownerKey, 32, 8);
System.Array.Copy(oks, 0, ownerKey, 40, 8);
// Algorithm 3.9.2
md.Update(ownerPassword, 0, Math.Min(ownerPassword.Length, 127));
md.Update(oks);
md.Update(userKey);
ac = new AESCipherCBCnoPad(true, md.Digest());
oeKey = ac.ProcessBlock(nextObjectKey, 0, nextObjectKey.Length);
// Algorithm 3.10
byte[] permsp = IVGenerator.GetIV(16);
permsp[0] = (byte)permissions;
permsp[1] = (byte)(permissions >> 8);
permsp[2] = (byte)(permissions >> 16);
permsp[3] = (byte)(permissions >> 24);
permsp[4] = (byte)(255);
permsp[5] = (byte)(255);
permsp[6] = (byte)(255);
permsp[7] = (byte)(255);
permsp[8] = encryptMetadata ? (byte)'T' : (byte)'F';
permsp[9] = (byte)'a';
permsp[10] = (byte)'d';
permsp[11] = (byte)'b';
ac = new AESCipherCBCnoPad(true, nextObjectKey);
aes256Perms = ac.ProcessBlock(permsp, 0, permsp.Length);
this.permissions = permissions;
this.encryptMetadata = encryptMetadata;
SetStandardHandlerDicEntries(encryptionDictionary, userKey, ownerKey);
SetAES256DicEntries(encryptionDictionary, oeKey, ueKey, aes256Perms, encryptMetadata, embeddedFilesOnly);
}
catch (Exception ex) {
throw new PdfException(PdfException.PdfEncryption, ex);
}
}
