diff --git a/briar-core/src/net/sf/briar/crypto/Sec1KeyParser.java b/briar-core/src/net/sf/briar/crypto/Sec1KeyParser.java
index 522a5543aa6da00191b6270c56716cc9346897e9..729e109154ff5d985da4bb1fea72613b58884717 100644
--- a/briar-core/src/net/sf/briar/crypto/Sec1KeyParser.java
+++ b/briar-core/src/net/sf/briar/crypto/Sec1KeyParser.java
@@ -28,7 +28,7 @@ class Sec1KeyParser implements KeyParser {
this.params = params;
this.modulus = modulus;
this.keyBits = keyBits;
- bytesPerInt = (int) Math.ceil(keyBits / 8.0);
+ bytesPerInt = keyBits + 7 / 8;
publicKeyBytes = 1 + 2 * bytesPerInt;
privateKeyBytes = bytesPerInt;
}
@@ -47,7 +47,7 @@ class Sec1KeyParser implements KeyParser {
if(x.compareTo(modulus) >= 0) throw new GeneralSecurityException();
// The y co-ordinate must be >= 0 and < q
byte[] yBytes = new byte[bytesPerInt];
- System.arraycopy(encodedKey, bytesPerInt + 1, yBytes, 0, bytesPerInt);
+ System.arraycopy(encodedKey, 1 + bytesPerInt, yBytes, 0, bytesPerInt);
BigInteger y = new BigInteger(1, yBytes); // Positive signum
if(y.compareTo(modulus) >= 0) throw new GeneralSecurityException();
// Verify that y^2 == x^3 + ax + b (mod p)
diff --git a/briar-core/src/net/sf/briar/crypto/Sec1PrivateKey.java b/briar-core/src/net/sf/briar/crypto/Sec1PrivateKey.java
index fc346e839e3dcef0dd7a5e696d50c03c8a4af5f1..e6a0fc0f6e512be4367e0cccb82f6267a8c37066 100644
--- a/briar-core/src/net/sf/briar/crypto/Sec1PrivateKey.java
+++ b/briar-core/src/net/sf/briar/crypto/Sec1PrivateKey.java
@@ -1,7 +1,5 @@
package net.sf.briar.crypto;
-import java.math.BigInteger;
-
import net.sf.briar.api.crypto.PrivateKey;
import org.spongycastle.crypto.params.ECPrivateKeyParameters;
@@ -9,20 +7,17 @@ import org.spongycastle.crypto.params.ECPrivateKeyParameters;
class Sec1PrivateKey implements PrivateKey {
private final ECPrivateKeyParameters key;
- private final int privateKeyBytes;
+ private final int bytesPerInt;
Sec1PrivateKey(ECPrivateKeyParameters key, int keyBits) {
this.key = key;
- privateKeyBytes = (int) Math.ceil(keyBits / 8.0);
+ bytesPerInt = keyBits + 7 / 8;
}
public byte[] getEncoded() {
- byte[] encodedKey = new byte[privateKeyBytes];
- BigInteger d = key.getD();
- // Copy up to privateKeyBytes bytes into exactly privateKeyBytes bytes
- byte[] dBytes = d.toByteArray();
- for(int i = 0; i < dBytes.length && i < privateKeyBytes; i++)
- encodedKey[privateKeyBytes - 1 - i] = dBytes[dBytes.length - 1 - i];
+ byte[] encodedKey = new byte[bytesPerInt];
+ byte[] d = key.getD().toByteArray();
+ Sec1Utils.convertToFixedLength(d, encodedKey, bytesPerInt, 0);
return encodedKey;
}
diff --git a/briar-core/src/net/sf/briar/crypto/Sec1PublicKey.java b/briar-core/src/net/sf/briar/crypto/Sec1PublicKey.java
index 2cb9a213c8038c54b0ce373ce4b1fcf6636fa023..a51ded2693e25630768e0dcf50b86926fa51eabd 100644
--- a/briar-core/src/net/sf/briar/crypto/Sec1PublicKey.java
+++ b/briar-core/src/net/sf/briar/crypto/Sec1PublicKey.java
@@ -1,7 +1,5 @@
package net.sf.briar.crypto;
-import java.math.BigInteger;
-
import net.sf.briar.api.crypto.PublicKey;
import org.spongycastle.crypto.params.ECPublicKeyParameters;
@@ -18,22 +16,18 @@ class Sec1PublicKey implements PublicKey {
Sec1PublicKey(ECPublicKeyParameters key, int keyBits) {
this.key = key;
- bytesPerInt = (int) Math.ceil(keyBits / 8.0);
+ bytesPerInt = keyBits + 7 / 8;
publicKeyBytes = 1 + 2 * bytesPerInt;
}
public byte[] getEncoded() {
byte[] encodedKey = new byte[publicKeyBytes];
encodedKey[0] = 4;
- BigInteger x = key.getQ().getX().toBigInteger();
- BigInteger y = key.getQ().getY().toBigInteger();
- // Copy up to bytesPerInt bytes into exactly bytesPerInt bytes
- byte[] xBytes = x.toByteArray();
- for(int i = 0; i < xBytes.length && i < bytesPerInt; i++)
- encodedKey[bytesPerInt - i] = xBytes[xBytes.length - 1 - i];
- byte[] yBytes = y.toByteArray();
- for(int i = 0; i < yBytes.length && i < bytesPerInt; i++)
- encodedKey[2 * bytesPerInt - i] = yBytes[yBytes.length - 1 - i];
+ byte[] x = key.getQ().getX().toBigInteger().toByteArray();
+ Sec1Utils.convertToFixedLength(x, encodedKey, bytesPerInt, 1);
+ byte[] y = key.getQ().getY().toBigInteger().toByteArray();
+ Sec1Utils.convertToFixedLength(y, encodedKey, bytesPerInt,
+ 1 + bytesPerInt);
return encodedKey;
}
diff --git a/briar-core/src/net/sf/briar/crypto/Sec1Utils.java b/briar-core/src/net/sf/briar/crypto/Sec1Utils.java
new file mode 100644
index 0000000000000000000000000000000000000000..debb6cb8657e9db735fe3eef136aed07331fb966
--- /dev/null
+++ b/briar-core/src/net/sf/briar/crypto/Sec1Utils.java
@@ -0,0 +1,15 @@
+package net.sf.briar.crypto;
+
+class Sec1Utils {
+
+ static void convertToFixedLength(byte[] src, byte[] dest, int destLen,
+ int destOff) {
+ if(src.length < destLen) {
+ destOff += destLen - src.length;
+ System.arraycopy(src, 0, dest, destOff, src.length);
+ } else {
+ int srcOff = src.length - destLen;
+ System.arraycopy(src, srcOff, dest, destOff, destLen);
+ }
+ }
+}
diff --git a/briar-tests/src/net/sf/briar/crypto/KeyEncodingAndParsingTest.java b/briar-tests/src/net/sf/briar/crypto/KeyEncodingAndParsingTest.java
index d46e9ee7bc248f9ceb3f13527aa06dff600fad42..d71dd3491c5899902feca25b46ae3fd278178152 100644
--- a/briar-tests/src/net/sf/briar/crypto/KeyEncodingAndParsingTest.java
+++ b/briar-tests/src/net/sf/briar/crypto/KeyEncodingAndParsingTest.java
@@ -1,6 +1,10 @@
package net.sf.briar.crypto;
import static org.junit.Assert.assertArrayEquals;
+
+import java.security.GeneralSecurityException;
+import java.util.Random;
+
import net.sf.briar.BriarTestCase;
import net.sf.briar.api.crypto.KeyPair;
import net.sf.briar.api.crypto.KeyParser;
@@ -47,6 +51,35 @@ public class KeyEncodingAndParsingTest extends BriarTestCase {
assertArrayEquals(secret, secret1);
}
+ @Test
+ public void testAgreementKeyParserByFuzzing() throws Exception {
+ KeyParser parser = crypto.getAgreementKeyParser();
+ // Generate a key pair to get the proper public key length
+ KeyPair p = crypto.generateAgreementKeyPair();
+ int pubLength = p.getPublic().getEncoded().length;
+ int privLength = p.getPrivate().getEncoded().length;
+ // Parse some random byte arrays - expect GeneralSecurityException
+ Random random = new Random();
+ byte[] pubFuzz = new byte[pubLength];
+ byte[] privFuzz = new byte[privLength];
+ for(int i = 0; i < 1000; i++) {
+ random.nextBytes(pubFuzz);
+ try {
+ parser.parsePublicKey(pubFuzz);
+ } catch(GeneralSecurityException expected) {
+ } catch(Exception e) {
+ fail();
+ }
+ random.nextBytes(privFuzz);
+ try {
+ parser.parsePrivateKey(privFuzz);
+ } catch(GeneralSecurityException expected) {
+ } catch(Exception e) {
+ fail();
+ }
+ }
+ }
+
@Test
public void testSignaturePublicKeyEncodingAndParsing() throws Exception {
KeyParser parser = crypto.getSignatureKeyParser();
@@ -80,4 +113,33 @@ public class KeyEncodingAndParsingTest extends BriarTestCase {
byte[] secret1 = crypto.deriveSharedSecret(bPriv, aPair.getPublic());
assertArrayEquals(secret, secret1);
}
+
+ @Test
+ public void testSignatureKeyParserByFuzzing() throws Exception {
+ KeyParser parser = crypto.getSignatureKeyParser();
+ // Generate a key pair to get the proper public key length
+ KeyPair p = crypto.generateSignatureKeyPair();
+ int pubLength = p.getPublic().getEncoded().length;
+ int privLength = p.getPrivate().getEncoded().length;
+ // Parse some random byte arrays - expect GeneralSecurityException
+ Random random = new Random();
+ byte[] pubFuzz = new byte[pubLength];
+ byte[] privFuzz = new byte[privLength];
+ for(int i = 0; i < 1000; i++) {
+ random.nextBytes(pubFuzz);
+ try {
+ parser.parsePublicKey(pubFuzz);
+ } catch(GeneralSecurityException expected) {
+ } catch(Exception e) {
+ fail();
+ }
+ random.nextBytes(privFuzz);
+ try {
+ parser.parsePrivateKey(privFuzz);
+ } catch(GeneralSecurityException expected) {
+ } catch(Exception e) {
+ fail();
+ }
+ }
+ }
}