LibreOffice Module oox (master)  1
binarycodec.cxx
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19 
20 #include "oox/core/binarycodec.hxx"
21 
22 #include <algorithm>
23 #include <string.h>
25 
26 #include <osl/diagnose.h>
29 
30 using namespace ::com::sun::star;
31 
32 namespace oox {
33 namespace core {
34 
35 namespace {
36 
38 template< typename Type >
39 inline void lclRotateLeft( Type& rnValue, size_t nBits )
40 {
41  OSL_ENSURE( nBits < sizeof( Type ) * 8, "lclRotateLeft - rotation count overflow" );
42  rnValue = static_cast< Type >( (rnValue << nBits) | (rnValue >> (sizeof( Type ) * 8 - nBits)) );
43 }
44 
46 template< typename Type >
47 inline void lclRotateLeft( Type& rnValue, size_t nBits, size_t nWidth )
48 {
49  OSL_ENSURE( (nBits < nWidth) && (nWidth < sizeof( Type ) * 8), "lclRotateLeft - rotation count overflow" );
50  Type nMask = static_cast< Type >( (1UL << nWidth) - 1 );
51  rnValue = static_cast< Type >(
52  ((rnValue << nBits) | ((rnValue & nMask) >> (nWidth - nBits))) & nMask );
53 }
54 
55 sal_Int32 lclGetLen( const sal_uInt8* pnPassData, sal_Int32 nBufferSize )
56 {
57  sal_Int32 nLen = 0;
58  while( (nLen < nBufferSize) && pnPassData[ nLen ] ) ++nLen;
59  return nLen;
60 }
61 
62 sal_uInt16 lclGetKey( const sal_uInt8* pnPassData, sal_Int32 nBufferSize )
63 {
64  sal_Int32 nLen = lclGetLen( pnPassData, nBufferSize );
65  if( nLen <= 0 ) return 0;
66 
67  sal_uInt16 nKey = 0;
68  sal_uInt16 nKeyBase = 0x8000;
69  sal_uInt16 nKeyEnd = 0xFFFF;
70  const sal_uInt8* pnChar = pnPassData + nLen - 1;
71  for( sal_Int32 nIndex = 0; nIndex < nLen; ++nIndex, --pnChar )
72  {
73  sal_uInt8 cChar = *pnChar & 0x7F;
74  for( size_t nBit = 0; nBit < 8; ++nBit )
75  {
76  lclRotateLeft( nKeyBase, 1 );
77  if( nKeyBase & 1 ) nKeyBase ^= 0x1020;
78  if( cChar & 1 ) nKey ^= nKeyBase;
79  cChar >>= 1;
80  lclRotateLeft( nKeyEnd, 1 );
81  if( nKeyEnd & 1 ) nKeyEnd ^= 0x1020;
82  }
83  }
84  return nKey ^ nKeyEnd;
85 }
86 
87 sal_uInt16 lclGetHash( const sal_uInt8* pnPassData, sal_Int32 nBufferSize )
88 {
89  sal_Int32 nLen = lclGetLen( pnPassData, nBufferSize );
90 
91  sal_uInt16 nHash = static_cast< sal_uInt16 >( nLen );
92  if( nLen > 0 )
93  nHash ^= 0xCE4B;
94 
95  const sal_uInt8* pnChar = pnPassData;
96  for( sal_Int32 nIndex = 0; nIndex < nLen; ++nIndex, ++pnChar )
97  {
98  sal_uInt16 cChar = *pnChar;
99  size_t nRot = static_cast< size_t >( (nIndex + 1) % 15 );
100  lclRotateLeft( cChar, nRot, 15 );
101  nHash ^= cChar;
102  }
103  return nHash;
104 }
105 
106 } // namespace
107 
108 sal_uInt16 CodecHelper::getPasswordHash( const AttributeList& rAttribs, sal_Int32 nElement )
109 {
110  sal_Int32 nPasswordHash = rAttribs.getIntegerHex( nElement, 0 );
111  OSL_ENSURE( (0 <= nPasswordHash) && (nPasswordHash <= SAL_MAX_UINT16), "CodecHelper::getPasswordHash - invalid password hash" );
112  return static_cast< sal_uInt16 >( ((0 <= nPasswordHash) && (nPasswordHash <= SAL_MAX_UINT16)) ? nPasswordHash : 0 );
113 }
114 
116  mnOffset( 0 ),
117  mnBaseKey( 0 ),
118  mnHash( 0 )
119 {
120  (void)memset( mpnKey, 0, sizeof( mpnKey ) );
121 }
122 
124 {
125  (void)memset( mpnKey, 0, sizeof( mpnKey ) );
126  mnBaseKey = mnHash = 0;
127 }
128 
129 void BinaryCodec_XOR::initKey( const sal_uInt8 pnPassData[ 16 ] )
130 {
131  // calculate base key and hash from passed password
132  mnBaseKey = lclGetKey( pnPassData, 16 );
133  mnHash = lclGetHash( pnPassData, 16 );
134 
135  static const sal_uInt8 spnFillChars[] =
136  {
137  0xBB, 0xFF, 0xFF, 0xBA,
138  0xFF, 0xFF, 0xB9, 0x80,
139  0x00, 0xBE, 0x0F, 0x00,
140  0xBF, 0x0F, 0x00, 0x00
141  };
142 
143  (void)memcpy( mpnKey, pnPassData, 16 );
144  sal_Int32 nLen = lclGetLen( pnPassData, 16 );
145  const sal_uInt8* pnFillChar = spnFillChars;
146  for (sal_Int32 nIndex = nLen; nIndex < static_cast<sal_Int32>(sizeof(mpnKey)); ++nIndex, ++pnFillChar )
147  mpnKey[ nIndex ] = *pnFillChar;
148 
149  // use little-endian base key to create key array
150  sal_uInt8 pnBaseKeyLE[ 2 ];
151  pnBaseKeyLE[ 0 ] = static_cast< sal_uInt8 >( mnBaseKey );
152  pnBaseKeyLE[ 1 ] = static_cast< sal_uInt8 >( mnBaseKey >> 8 );
153  sal_uInt8* pnKeyChar = mpnKey;
154  for (sal_Int32 nIndex = 0; nIndex < static_cast<sal_Int32>(sizeof(mpnKey)); ++nIndex, ++pnKeyChar )
155  {
156  *pnKeyChar ^= pnBaseKeyLE[ nIndex & 1 ];
157  lclRotateLeft( *pnKeyChar, 2/*nRotateSize*/ );
158  }
159 }
160 
161 bool BinaryCodec_XOR::initCodec( const uno::Sequence< beans::NamedValue >& aData )
162 {
163  bool bResult = false;
164 
165  ::comphelper::SequenceAsHashMap aHashData( aData );
166  uno::Sequence< sal_Int8 > aKey = aHashData.getUnpackedValueOrDefault("XOR95EncryptionKey", uno::Sequence< sal_Int8 >() );
167 
168  if ( aKey.getLength() == 16 )
169  {
170  (void)memcpy( mpnKey, aKey.getConstArray(), 16 );
171  bResult = true;
172 
173  mnBaseKey = (sal_uInt16)aHashData.getUnpackedValueOrDefault("XOR95BaseKey", (sal_Int16)0 );
174  mnHash = (sal_uInt16)aHashData.getUnpackedValueOrDefault("XOR95PasswordHash", (sal_Int16)0 );
175  }
176  else
177  OSL_FAIL( "Unexpected key size!" );
178 
179  return bResult;
180 }
181 
182 uno::Sequence< beans::NamedValue > BinaryCodec_XOR::getEncryptionData()
183 {
185  aHashData[ OUString("XOR95EncryptionKey") ] <<= uno::Sequence<sal_Int8>( reinterpret_cast<sal_Int8*>(mpnKey), 16 );
186  aHashData[ OUString("XOR95BaseKey") ] <<= (sal_Int16)mnBaseKey;
187  aHashData[ OUString("XOR95PasswordHash") ] <<= (sal_Int16)mnHash;
188 
189  return aHashData.getAsConstNamedValueList();
190 }
191 
192 bool BinaryCodec_XOR::verifyKey( sal_uInt16 nKey, sal_uInt16 nHash ) const
193 {
194  return (nKey == mnBaseKey) && (nHash == mnHash);
195 }
196 
197 bool BinaryCodec_XOR::skip( sal_Int32 nBytes )
198 {
199  mnOffset = static_cast< sal_Int32 >( (mnOffset + nBytes) & 0x0F );
200  return true;
201 }
202 
204 {
205  mhCipher = rtl_cipher_create( rtl_Cipher_AlgorithmARCFOUR, rtl_Cipher_ModeStream );
206  OSL_ENSURE( mhCipher != nullptr, "BinaryCodec_RCF::BinaryCodec_RCF - cannot create cipher" );
207 
208  mhDigest = rtl_digest_create( rtl_Digest_AlgorithmMD5 );
209  OSL_ENSURE( mhDigest != nullptr, "BinaryCodec_RCF::BinaryCodec_RCF - cannot create digest" );
210 
211  (void)memset( mpnDigestValue, 0, sizeof( mpnDigestValue ) );
212  (void)memset (mpnUnique, 0, sizeof(mpnUnique));
213 }
214 
216 {
217  (void)memset( mpnDigestValue, 0, sizeof( mpnDigestValue ) );
218  (void)memset (mpnUnique, 0, sizeof(mpnUnique));
219  rtl_digest_destroy( mhDigest );
220  rtl_cipher_destroy( mhCipher );
221 }
222 
223 bool BinaryCodec_RCF::initCodec( const uno::Sequence< beans::NamedValue >& aData )
224 {
225  bool bResult = false;
226 
227  ::comphelper::SequenceAsHashMap aHashData( aData );
228  uno::Sequence< sal_Int8 > aKey = aHashData.getUnpackedValueOrDefault("STD97EncryptionKey", uno::Sequence< sal_Int8 >() );
229 
230  if ( aKey.getLength() == RTL_DIGEST_LENGTH_MD5 )
231  {
232  (void)memcpy( mpnDigestValue, aKey.getConstArray(), RTL_DIGEST_LENGTH_MD5 );
233  uno::Sequence< sal_Int8 > aUniqueID = aHashData.getUnpackedValueOrDefault("STD97UniqueID", uno::Sequence< sal_Int8 >() );
234  if ( aUniqueID.getLength() == 16 )
235  {
236  (void)memcpy( mpnUnique, aUniqueID.getConstArray(), 16 );
237  bResult = false;
238  }
239  else
240  OSL_FAIL( "Unexpected document ID!" );
241  }
242  else
243  OSL_FAIL( "Unexpected key size!" );
244 
245  return bResult;
246 }
247 
248 uno::Sequence< beans::NamedValue > BinaryCodec_RCF::getEncryptionData()
249 {
251  aHashData[ OUString("STD97EncryptionKey") ] <<= uno::Sequence< sal_Int8 >( reinterpret_cast<sal_Int8*>(mpnDigestValue), RTL_DIGEST_LENGTH_MD5 );
252  aHashData[ OUString("STD97UniqueID") ] <<= uno::Sequence< sal_Int8 >( reinterpret_cast<sal_Int8*>(mpnUnique), 16 );
253 
254  return aHashData.getAsConstNamedValueList();
255 }
256 
257 void BinaryCodec_RCF::initKey( const sal_uInt16 pnPassData[ 16 ], const sal_uInt8 pnSalt[ 16 ] )
258 {
259  uno::Sequence< sal_Int8 > aKey = ::comphelper::DocPasswordHelper::GenerateStd97Key( pnPassData, uno::Sequence< sal_Int8 >( reinterpret_cast<sal_Int8 const *>(pnSalt), 16 ) );
260  // Fill raw digest of above updates into DigestValue.
261 
262  if ( aKey.getLength() == sizeof(mpnDigestValue) )
263  (void)memcpy ( mpnDigestValue, aKey.getConstArray(), sizeof(mpnDigestValue) );
264  else
265  memset( mpnDigestValue, 0, sizeof(mpnDigestValue) );
266 
267  (void)memcpy( mpnUnique, pnSalt, 16 );
268 }
269 
270 bool BinaryCodec_RCF::verifyKey( const sal_uInt8 pnVerifier[ 16 ], const sal_uInt8 pnVerifierHash[ 16 ] )
271 {
272  if( !startBlock( 0 ) )
273  return false;
274 
275  sal_uInt8 pnDigest[ RTL_DIGEST_LENGTH_MD5 ];
276  sal_uInt8 pnBuffer[ 64 ];
277 
278  // decode salt data into buffer
279  rtl_cipher_decode( mhCipher, pnVerifier, 16, pnBuffer, sizeof( pnBuffer ) );
280 
281  pnBuffer[ 16 ] = 0x80;
282  (void)memset( pnBuffer + 17, 0, sizeof( pnBuffer ) - 17 );
283  pnBuffer[ 56 ] = 0x80;
284 
285  // fill raw digest of buffer into digest
286  rtl_digest_updateMD5( mhDigest, pnBuffer, sizeof( pnBuffer ) );
287  rtl_digest_rawMD5( mhDigest, pnDigest, sizeof( pnDigest ) );
288 
289  // decode original salt digest into buffer
290  rtl_cipher_decode( mhCipher, pnVerifierHash, 16, pnBuffer, sizeof( pnBuffer ) );
291 
292  // compare buffer with computed digest
293  bool bResult = memcmp( pnBuffer, pnDigest, sizeof( pnDigest ) ) == 0;
294 
295  // erase buffer and digest arrays and leave
296  rtl_secureZeroMemory (pnBuffer, sizeof(pnBuffer));
297  rtl_secureZeroMemory (pnDigest, sizeof(pnDigest));
298  return bResult;
299 }
300 
301 bool BinaryCodec_RCF::startBlock( sal_Int32 nCounter )
302 {
303  // initialize key data array
304  sal_uInt8 pnKeyData[ 64 ];
305  (void)memset( pnKeyData, 0, sizeof( pnKeyData ) );
306 
307  // fill 40 bit of digest value into [0..4]
308  (void)memcpy( pnKeyData, mpnDigestValue, 5 );
309 
310  // fill little-endian counter into [5..8], static_cast masks out unneeded bits
311  pnKeyData[ 5 ] = static_cast< sal_uInt8 >( nCounter );
312  pnKeyData[ 6 ] = static_cast< sal_uInt8 >( nCounter >> 8 );
313  pnKeyData[ 7 ] = static_cast< sal_uInt8 >( nCounter >> 16 );
314  pnKeyData[ 8 ] = static_cast< sal_uInt8 >( nCounter >> 24 );
315 
316  pnKeyData[ 9 ] = 0x80;
317  pnKeyData[ 56 ] = 0x48;
318 
319  // fill raw digest of key data into key data
320  (void)rtl_digest_updateMD5( mhDigest, pnKeyData, sizeof( pnKeyData ) );
321  (void)rtl_digest_rawMD5( mhDigest, pnKeyData, RTL_DIGEST_LENGTH_MD5 );
322 
323  // initialize cipher with key data (for decoding)
324  rtlCipherError eResult =
325  rtl_cipher_init( mhCipher, rtl_Cipher_DirectionDecode, pnKeyData, RTL_DIGEST_LENGTH_MD5, nullptr, 0 );
326 
327  // erase key data array and leave
328  rtl_secureZeroMemory (pnKeyData, sizeof(pnKeyData));
329  return eResult == rtl_Cipher_E_None;
330 }
331 
332 bool BinaryCodec_RCF::decode( sal_uInt8* pnDestData, const sal_uInt8* pnSrcData, sal_Int32 nBytes )
333 {
334  rtlCipherError eResult = rtl_cipher_decode( mhCipher,
335  pnSrcData, static_cast< sal_Size >( nBytes ),
336  pnDestData, static_cast< sal_Size >( nBytes ) );
337  return eResult == rtl_Cipher_E_None;
338 }
339 
340 } // namespace core
341 } // namespace oox
342 
343 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
Type
css::uno::Sequence< css::beans::NamedValue > getEncryptionData()
Retrieves the encryption data.
signed char sal_Int8
sal_Int32 mnOffset
Key offset.
OOX_DLLPUBLIC sal_uInt16 getPasswordHash(const AttributeList &rAttribs, sal_Int32 nElement)
Returns the password hash if it is in the required 16-bit limit.
sal_uInt8 mpnKey[16]
Encryption key.
BinaryCodec_RCF()
Default constructor.
bool startBlock(sal_Int32 nCounter)
Rekeys the codec using the specified counter.
bool initCodec(const css::uno::Sequence< css::beans::NamedValue > &aData)
Initializes the algorithm with the encryption data.
bool decode(sal_uInt8 *pnDestData, const sal_uInt8 *pnSrcData, sal_Int32 nBytes)
Decodes a block of memory.
#define SAL_MAX_UINT16
const css::uno::Sequence< css::beans::NamedValue > getAsConstNamedValueList() const
sal_uInt16 mnBaseKey
Base key from password.
TValueType getUnpackedValueOrDefault(const OUString &sKey, const TValueType &aDefault) const
bool skip(sal_Int32 nBytes)
Lets the cipher skip a specific amount of bytes.
void initKey(const sal_uInt8 pnPassData[16])
Initializes the algorithm with the specified password.
bool verifyKey(const sal_uInt8 pnVerifier[16], const sal_uInt8 pnVerifierHash[16])
Verifies the validity of the password using the passed salt data.
static css::uno::Sequence< sal_Int8 > GenerateStd97Key(const OUString &aPassword, const css::uno::Sequence< sal_Int8 > &aDocId)
bool initCodec(const css::uno::Sequence< css::beans::NamedValue > &aData)
Initializes the algorithm with the encryption data.
sal_uInt16 mnHash
Hash value from password.
BinaryCodec_XOR()
Default constructor.
Provides access to attribute values of an element.
css::uno::Sequence< css::beans::NamedValue > getEncryptionData()
Retrieves the encryption data.
sal_uInt8 mpnDigestValue[RTL_DIGEST_LENGTH_MD5]
OptValue< sal_Int32 > getIntegerHex(sal_Int32 nAttrToken) const
Returns the 32-bit signed integer value of the specified attribute (hexadecimal). ...
unsigned char sal_uInt8
void initKey(const sal_uInt16 pnPassData[16], const sal_uInt8 pnSalt[16])
Initializes the algorithm with the specified password and document ID.
GUIDCNamePair aData
Definition: olehelper.cxx:99
bool verifyKey(sal_uInt16 nKey, sal_uInt16 nHash) const
Verifies the validity of the password using the passed key and hash.
typedef void(CALLTYPE *GetFuncDataPtr)(sal_uInt16 &nNo