Symaptic: os/security/crypto/weakcrypto/source/pbe/pbeset.cpp@bde4ae8d615e

     1 /*

     2 * Copyright (c) 2002-2009 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of the License "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:

    15 *

    16 */

    19 #include <e32std.h>

    20 #include <random.h>

    21 #include <pbedata.h>

    22 #include "pkcs5kdf.h"

    23 #include "pbencryptor.h"

    24 #include "pbe.h"

    25 #include <securityerr.h>

    26 #include "pbesymmetricfactory.h"

    28 EXPORT_C CPBEncryptSet* CPBEncryptSet::NewL(const TPBPassword& aPassword)

    29 	{

    30 	CPBEncryptSet* self = NewLC(aPassword);

    31 	CleanupStack::Pop();

    32 	return self;

    33 	}

    35 EXPORT_C CPBEncryptSet* CPBEncryptSet::NewLC(const TPBPassword& aPassword)

    36 	{

    37 	CPBEncryptSet* self = new(ELeave) CPBEncryptSet;

    38 	CleanupStack::PushL(self);

    39 	self->ConstructL(aPassword.Password());

    40 	return self;

    41 	}

    43 EXPORT_C CPBEncryptSet* CPBEncryptSet::NewL(const TPBPassword& aPassword,

    44 	const TPBECipher aCipher)

    45 	{

    46 	CPBEncryptSet* self = NewLC(aPassword, aCipher);

    47 	CleanupStack::Pop();

    48 	return self;

    49 	}

    51 EXPORT_C CPBEncryptSet* CPBEncryptSet::NewLC(const TPBPassword& aPassword,

    52 	const TPBECipher aCipher)

    53 	{

    54 	CPBEncryptSet* self = new(ELeave) CPBEncryptSet;

    55 	CleanupStack::PushL(self);

    56 	self->ConstructL(aPassword.Password(), aCipher);

    57 	return self;

    58 	}

    60 EXPORT_C CPBEncryptSet* CPBEncryptSet::NewL(const TPBPassword& aPassword,

    61 	const CPBEncryptParms& aParms)

    62 	{

    63 	CPBEncryptSet* self = NewLC(aPassword, aParms);

    64 	CleanupStack::Pop();

    65 	return self;

    66 	}

    68 EXPORT_C CPBEncryptSet* CPBEncryptSet::NewLC(const TPBPassword& aPassword,

    69 	const CPBEncryptParms& aParms)

    70 	{

    71 	CPBEncryptSet* self = new(ELeave) CPBEncryptSet;

    72 	CleanupStack::PushL(self);

    73 	self->ConstructL(aPassword.Password(), aParms);

    74 	return self;

    75 	}

    77 EXPORT_C CPBEncryptSet* CPBEncryptSet::NewL(const CPBEncryptionData& aData,

    78 	const TDesC8& aEncryptedKey, const TPBPassword& aPassword)

    79 	{

    80 	CPBEncryptSet* self = NewLC(aData, aEncryptedKey, aPassword);

    81 	CleanupStack::Pop();

    82 	return self;

    83 	}

    85 EXPORT_C CPBEncryptSet* CPBEncryptSet::NewLC(const CPBEncryptionData& aData,

    86 	const TDesC8& aEncryptedKey, const TPBPassword& aPassword)

    87 	{

    88 	CPBEncryptSet* self = new(ELeave) CPBEncryptSet;

    89 	CleanupStack::PushL(self);

    90 	self->ConstructL(aData, aEncryptedKey, aPassword);

    91 	return self;

    92 	}

    94 void CPBEncryptSet::ConstructL(const TDesC8& aPassword)

    95 	{

    96 	CPBEncryptElement::ConstructL(aPassword);

    97 	ConstructMasterKeyL();

    98 	}

   100 void CPBEncryptSet::ConstructL(const TDesC8& aPassword,

   101 	const TPBECipher aCipher)

   102 	{

   103 	CPBEncryptElement::ConstructL(aPassword, aCipher);

   104 	ConstructMasterKeyL();

   105 	}

   107 void CPBEncryptSet::ConstructL(const TDesC8& aPassword,

   108 	const CPBEncryptParms& aParms)

   109 	{

   110 	CPBEncryptElement::ConstructL(aPassword, aParms);

   111 	ConstructMasterKeyL();

   112 	}

   114 void CPBEncryptSet::ConstructMasterKeyL(void)

   115 	{

   116 	TBuf8<KAESKeyBytes256> masterKey(KAESKeyBytes256);

   117 	TRandom::RandomL(masterKey);

   118 	iEncryptedMasterKey = HBufC8::NewL(KAESKeyBytes256);

   119 	EncryptMasterKeyL(masterKey);

   120 	}

   122 void CPBEncryptSet::ConstructL(const CPBEncryptionData& aData,

   123 	const TDesC8& aEncryptedMasterKey, const TPBPassword& aPassword)

   124 	{

   125 	CPBEncryptElement::ConstructL(aData, aPassword);

   126 	iEncryptedMasterKey = aEncryptedMasterKey.AllocL();

   127 	}

   129 EXPORT_C void CPBEncryptSet::ChangePasswordL(const TPBPassword& aNewPassword)

   130 	{

   131 	//1) Decrypt master key with old encrypt key

   132 	TBuf8<KPBEMaxCipherKeyBytes> masterKey;

   133 	DecryptMasterKeyL(masterKey);

   135 	//2) create new encrypt parms

   137 	TBuf8<KPBEMaxSaltBytes> authSalt(KPBEMaxSaltBytes);

   138 	TRandom::RandomL(authSalt);

   140 	//3) create a totally new CPBEncryptionData representing the new password

   141 	CPBEncryptionData* newData = CPBEncryptionData::NewL(

   142 		aNewPassword.Password(), authSalt, iData->EncryptParms());

   144 	delete iData;

   145 	iData = newData;

   147 	// regenerate the password using a maximum length salt.

   148 	CPBEncryptParms& epNonConst =

   149 		const_cast<CPBEncryptParms&>(iData->EncryptParms());

   150 	epNonConst.ResizeSaltL(KPBEMaxSaltBytes);

   152 	TPtr8 iEncryptKeyBuf(iEncryptKey->Des());

   153 	iEncryptKeyBuf.SetLength(PBE::GetKeyBytes(iData->EncryptParms().Cipher()));

   155 	iData->EncryptParms().DeriveKeyL(aNewPassword.Password(), iEncryptKeyBuf);

   157 	//4) Encrypt master key with new encrypt key

   158 	EncryptMasterKeyL(masterKey);

   159 	}

   161 EXPORT_C const TDesC8& CPBEncryptSet::EncryptedMasterKey(void) const

   162 	{

   163 	return *iEncryptedMasterKey;

   164 	}

   166 CPBEncryptor* CPBEncryptSet::NewEncryptLC(void) const

   167 	{

   168 	CPBEncryptor* encryptor = NewEncryptL();

   169 	CleanupStack::PushL(encryptor);

   170 	return encryptor;

   171 	}

   173 CPBEncryptor* CPBEncryptSet::NewEncryptL(void) const

   174 	{

   175 	TBuf8<KPBEMaxCipherKeyBytes> masterKey;

   176 	DecryptMasterKeyL(masterKey);

   178 	CPBEncryptor* encryptor = 0;

   179 	//make sure the masterkey we pass is exactly the right length for the cipher

   180 	encryptor = CPBEncryptorSet::NewL(iData->EncryptParms().Cipher(),

   181 		masterKey.Left(PBE::GetKeyBytes(iData->EncryptParms().Cipher())));

   182 	return encryptor;

   183 	}

   185 CPBDecryptor* CPBEncryptSet::NewDecryptLC(void) const

   186 	{

   187 	CPBDecryptor* decryptor = NewDecryptL();

   188 	CleanupStack::PushL(decryptor);

   189 	return decryptor;

   190 	}

   192 CPBDecryptor* CPBEncryptSet::NewDecryptL(void) const

   193 	{

   194 	TBuf8<KPBEMaxCipherKeyBytes> masterKey;

   195 	DecryptMasterKeyL(masterKey);

   197 	CPBDecryptor* decryptor = 0;

   198 	//make sure the masterkey we pass is exactly the right length for the cipher

   199 	decryptor = CPBDecryptorSet::NewL(iData->EncryptParms().Cipher(),

   200 		masterKey.Left(PBE::GetKeyBytes(iData->EncryptParms().Cipher())));

   201 	return decryptor;

   202 	}

   204 void CPBEncryptSet::DecryptMasterKeyL(TDes8& aMasterKey) const

   205 	{

   206 	CPBDecryptorElement* decryptor = CPBDecryptorElement::NewLC(

   207 		iData->EncryptParms().Cipher(), *iEncryptKey, iData->EncryptParms().IV());

   208 	aMasterKey.SetLength(0);

   209 	decryptor->Process(*iEncryptedMasterKey, aMasterKey);

   210 	CleanupStack::PopAndDestroy(decryptor);

   211 	}

   213 void CPBEncryptSet::EncryptMasterKeyL(const TDesC8& aMasterKey)

   214 	{

   215 	CPBEncryptorElement* encryptor = CPBEncryptorElement::NewLC(

   216 		iData->EncryptParms().Cipher(), *iEncryptKey, iData->EncryptParms().IV());

   217 	TPtr8 encryptedMasterKeyBuf(iEncryptedMasterKey->Des());

   218 	encryptedMasterKeyBuf.SetLength(0);

   219 	encryptor->Process(aMasterKey, encryptedMasterKeyBuf);

   220 	CleanupStack::PopAndDestroy(encryptor);

   221 	}

   223 CPBEncryptSet::CPBEncryptSet()

   224 	{

   225 	}

   227 CPBEncryptSet::~CPBEncryptSet()

   228 	{

   229 	delete iEncryptedMasterKey;

   230 	}

   232 // Warning: This function is only valid BEFORE you call NewEncryptL

   233 // After creating the cipher, ask it about itself, not me!

   234 // This is _very_ dodgy as I assume all sorts of things about the encryptor.

   235 // 1) That it uses SSLv3 or similar style padding

   236 // 2) That it stores the IV for that stream at the front.

   237 // This is here for specific application that requires this and aren't able to

   238 // actually construct the cipher and ask it.  In almost all other cases you

   239 // should construct the cipher and ask it.

   240 TInt CPBEncryptSet::MaxCiphertextLength(TInt aPlaintextLength) const

   241     {

   242 	TUint blocksize = PBE::GetBlockBytes(iData->EncryptParms().Cipher());

   243 	TUint padding = blocksize - aPlaintextLength % blocksize;

   244 	//totallength = blocksize of iv hidden at beginning + inputLength + padding

   245 	return blocksize + aPlaintextLength + padding;

   246     }

   248 // Warning: This function is only valid BEFORE you call NewDecryptL

   249 // After creating the cipher, ask it about itself, not me!

   250 TInt CPBEncryptSet::MaxPlaintextLength(TInt aCiphertextLength) const

   251     {

   252 	/*It's impossible to determine anything about how much padding will be

   253 	 * removed.  So we'll return a max length that is longer than will ever

   254 	 * happen by at most a blocksize - 1.

   255 	 */

   256 	//In all cases SSLv3 padding has at least one byte of padding.

   257 	TUint blocksize = PBE::GetBlockBytes(iData->EncryptParms().Cipher());

   258 	//totallength = inputlength - iv hidden at beginning - 1 byte of padding

   259     return aCiphertextLength - blocksize - 1;

   260     }

author	sl@SLION-WIN7.fritz.box
	Fri, 15 Jun 2012 03:10:57 +0200
changeset 0	bde4ae8d615e
permissions	-rw-r--r--