mirrors/cryptomator
1
0
Fork 0
mirror of https://github.com/cryptomator/cryptomator.git synced 2026-05-21 12:11:28 +00:00
Code Issues Packages Projects Releases Wiki Activity

- file name encryption is deterministic again (broken by fix for #7)

Browse Source 
- improved unit test to avoid this mistake in the future
This commit is contained in:
Sebastian Stenzel
2014-12-30 20:06:05 +01:00
parent ebea3dae65
commit 4cb9da7252
2 changed files with 13 additions and 10 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
main/crypto-aes/src/main/java/org/cryptomator/crypto/aes256/Aes256Cryptor.java
View File

@@ -300,13 +300,13 @@ public class Aes256Cryptor extends AbstractCryptor implements AesCryptographicCo
* {@link FileNamingConventions#LONG_NAME_FILE_EXT}.
*/
private String encryptPathComponent(final String cleartext, final SecretKey key, CryptorIOSupport ioSupport) throws IllegalBlockSizeException, BadPaddingException, IOException {
final byte[] ivRandomPart = randomData(FILE_NAME_IV_LENGTH);
final long cleartextHash = crc32Sum(cleartext.getBytes());
final ByteBuffer iv = ByteBuffer.allocate(AES_BLOCK_LENGTH);
iv.put(ivRandomPart);
iv.putLong(cleartextHash);
final Cipher cipher = this.cipher(FILE_NAME_CIPHER, key, iv.array(), Cipher.ENCRYPT_MODE);
final byte[] cleartextBytes = cleartext.getBytes(Charsets.UTF_8);
final byte[] encryptedBytes = cipher.doFinal(cleartextBytes);
final String ivAndCiphertext = ENCRYPTED_FILENAME_CODEC.encodeAsString(ivRandomPart) + IV_PREFIX_SEPARATOR + ENCRYPTED_FILENAME_CODEC.encodeAsString(encryptedBytes);
final String ivAndCiphertext = Long.toHexString(cleartextHash) + IV_PREFIX_SEPARATOR + ENCRYPTED_FILENAME_CODEC.encodeAsString(encryptedBytes);
if (ivAndCiphertext.length() + BASIC_FILE_EXT.length() > ENCRYPTED_FILENAME_LENGTH_LIMIT) {
final String crc32 = Long.toHexString(crc32Sum(ivAndCiphertext.getBytes()));
@@ -354,11 +354,10 @@ public class Aes256Cryptor extends AbstractCryptor implements AesCryptographicCo
throw new IllegalArgumentException("Unsupported path component: " + encrypted);
}
final String ivRandomPartStr = StringUtils.substringBefore(ivAndCiphertext, IV_PREFIX_SEPARATOR);
final String cleartextHash = StringUtils.substringBefore(ivAndCiphertext, IV_PREFIX_SEPARATOR);
final String ciphertext = StringUtils.substringAfter(ivAndCiphertext, IV_PREFIX_SEPARATOR);
final byte[] ivRandomPart = ENCRYPTED_FILENAME_CODEC.decode(ivRandomPartStr);
final ByteBuffer iv = ByteBuffer.allocate(AES_BLOCK_LENGTH);
iv.put(ivRandomPart);
iv.putLong(Long.parseLong(cleartextHash, 16));
final Cipher cipher = this.cipher(FILE_NAME_CIPHER, key, iv.array(), Cipher.DECRYPT_MODE);
final byte[] encryptedBytes = ENCRYPTED_FILENAME_CODEC.decode(ciphertext);

12
main/crypto-aes/src/test/java/org/cryptomator/crypto/aes256/Aes256CryptorTest.java
View File

@@ -134,15 +134,19 @@ public class Aes256CryptorTest {
// short path components
final String originalPath1 = "foo/bar/baz";
final String encryptedPath1 = cryptor.encryptPath(originalPath1, '/', '/', ioSupportMock);
final String decryptedPath1 = cryptor.decryptPath(encryptedPath1, '/', '/', ioSupportMock);
final String encryptedPath1a = cryptor.encryptPath(originalPath1, '/', '/', ioSupportMock);
final String encryptedPath1b = cryptor.encryptPath(originalPath1, '/', '/', ioSupportMock);
Assert.assertEquals(encryptedPath1a, encryptedPath1b);
final String decryptedPath1 = cryptor.decryptPath(encryptedPath1a, '/', '/', ioSupportMock);
Assert.assertEquals(originalPath1, decryptedPath1);
// long path components
final String str50chars = "aaaaaaaaaabbbbbbbbbbccccccccccddddddddddeeeeeeeeee";
final String originalPath2 = "foo/" + str50chars + str50chars + str50chars + str50chars + str50chars + "/baz";
final String encryptedPath2 = cryptor.encryptPath(originalPath2, '/', '/', ioSupportMock);
final String decryptedPath2 = cryptor.decryptPath(encryptedPath2, '/', '/', ioSupportMock);
final String encryptedPath2a = cryptor.encryptPath(originalPath2, '/', '/', ioSupportMock);
final String encryptedPath2b = cryptor.encryptPath(originalPath2, '/', '/', ioSupportMock);
Assert.assertEquals(encryptedPath2a, encryptedPath2b);
final String decryptedPath2 = cryptor.decryptPath(encryptedPath2a, '/', '/', ioSupportMock);
Assert.assertEquals(originalPath2, decryptedPath2);
}