diff options
| author | Daniel Gultsch <daniel@gultsch.de> | 2016-12-20 16:12:12 +0100 |
|---|---|---|
| committer | Daniel Gultsch <daniel@gultsch.de> | 2016-12-20 16:12:12 +0100 |
| commit | e5fff42b10ba21bffa68c4c091e7c6126f8f0652 (patch) | |
| tree | 03d866f9d67981ba353db2c15313cf2f3b5a7917 | |
| parent | fbbf1a37b47b3967699bdb88ac31f5959b34dba6 (diff) | |
added omemo padding but disabled by Config.java flag
| -rw-r--r-- | src/main/java/eu/siacs/conversations/Config.java | 1 | ||||
| -rw-r--r-- | src/main/java/eu/siacs/conversations/crypto/axolotl/XmppAxolotlMessage.java | 20 |
2 files changed, 19 insertions, 2 deletions
diff --git a/src/main/java/eu/siacs/conversations/Config.java b/src/main/java/eu/siacs/conversations/Config.java index dbd27baf..fd8dc7be 100644 --- a/src/main/java/eu/siacs/conversations/Config.java +++ b/src/main/java/eu/siacs/conversations/Config.java @@ -82,6 +82,7 @@ public final class Config { public static final long OMEMO_AUTO_EXPIRY = 7 * MILLISECONDS_IN_DAY; public static final boolean REMOVE_BROKEN_DEVICES = false; + public static final boolean OMEMO_PADDING = false; public static final boolean DISABLE_PROXY_LOOKUP = false; //useful to debug ibb diff --git a/src/main/java/eu/siacs/conversations/crypto/axolotl/XmppAxolotlMessage.java b/src/main/java/eu/siacs/conversations/crypto/axolotl/XmppAxolotlMessage.java index 981b93ec..3fcd0fcf 100644 --- a/src/main/java/eu/siacs/conversations/crypto/axolotl/XmppAxolotlMessage.java +++ b/src/main/java/eu/siacs/conversations/crypto/axolotl/XmppAxolotlMessage.java @@ -162,7 +162,7 @@ public class XmppAxolotlMessage { IvParameterSpec ivSpec = new IvParameterSpec(iv); Cipher cipher = Cipher.getInstance(CIPHERMODE, PROVIDER); cipher.init(Cipher.ENCRYPT_MODE, secretKey, ivSpec); - this.ciphertext = cipher.doFinal(plaintext.getBytes()); + this.ciphertext = cipher.doFinal(Config.OMEMO_PADDING ? getPaddedBytes(plaintext) : plaintext.getBytes()); } catch (NoSuchAlgorithmException | NoSuchPaddingException | InvalidKeyException | IllegalBlockSizeException | BadPaddingException | NoSuchProviderException | InvalidAlgorithmParameterException e) { @@ -170,6 +170,22 @@ public class XmppAxolotlMessage { } } + private static byte[] getPaddedBytes(String plaintext) { + int plainLength = plaintext.getBytes().length; + int pad = Math.max(64,(plainLength / 32 + 1) * 32) - plainLength; + SecureRandom random = new SecureRandom(); + int left = random.nextInt(pad); + int right = pad - left; + StringBuilder builder = new StringBuilder(plaintext); + for(int i = 0; i < left; ++i) { + builder.insert(0,random.nextBoolean() ? "\t" : " "); + } + for(int i = 0; i < right; ++i) { + builder.append(random.nextBoolean() ? "\t" : " "); + } + return builder.toString().getBytes(); + } + public Jid getFrom() { return this.from; } @@ -239,7 +255,7 @@ public class XmppAxolotlMessage { cipher.init(Cipher.DECRYPT_MODE, keySpec, ivSpec); String plaintext = new String(cipher.doFinal(ciphertext)); - plaintextMessage = new XmppAxolotlPlaintextMessage(plaintext, session.getFingerprint()); + plaintextMessage = new XmppAxolotlPlaintextMessage(Config.OMEMO_PADDING ? plaintext.trim() : plaintext, session.getFingerprint()); } catch (NoSuchAlgorithmException | NoSuchPaddingException | InvalidKeyException | InvalidAlgorithmParameterException | IllegalBlockSizeException |