Skip to content

Commit

Permalink
Merge pull request #25 from dpatriarche/issues/24
Browse files Browse the repository at this point in the history 
Fix issue 24 (#24)
  • Loading branch information
@firaja
firaja authored Feb 4, 2021
2 parents 9e2e97b + 3e835a1 commit c52c438
Show file tree
Hide file tree
Showing 5 changed files with 90 additions and 26 deletions.
6 changes: 6 additions & 0 deletions README.md
View file
Original file line number Diff line number Diff line change
Expand Up @@ -114,6 +114,12 @@ boolean verification = Password.check(password, hash).addSalt(salt).addPepper(pe
boolean verification = Password.check(password, hash).withArgon2();
```

Some algorithms encode into the hash the parameters that were used to compute that hash, notably BCrypt, SCrypt, and Argon2.
When checking a hash, you can use the parameters from the hash rather than Password4j's configured defaults.
```java
// Verify with Argon2, reads the salt and parameters from the given hash.
boolean verification = Password.check(password, hash)..with(Argon2Function.getInstanceFromHash(hash)));
```

## Update the hash
When a configuration is not considered anymore secure you can
Expand Down
8 changes: 7 additions & 1 deletion src/main/java/com/password4j/AlgorithmFinder.java
View file
Original file line number Diff line number Diff line change
Expand Up @@ -240,6 +240,11 @@ public static BCryptFunction getBCryptInstance()
* <td>hash.scrypt.parallelization</td>
* <td>1</td>
* </tr>
* <tr>
* <td>Derived Key Length (dkLen)</td>
* <td>hash.scrypt.derivedKeyLength</td>
* <td>64</td>
* </tr>
* </table>
*
* @return a {@link SCryptFunction}
Expand All @@ -250,7 +255,8 @@ public static SCryptFunction getSCryptInstance()
int workFactor = PropertyReader.readInt("hash.scrypt.workfactor", 32_768, "SCrypt work factor (N) is not defined");
int resources = PropertyReader.readInt("hash.scrypt.resources", 8, "SCrypt resources (r) is not defined");
int parallelization = PropertyReader.readInt("hash.scrypt.parallelization", 1, "SCrypt parallelization (p) is not defined");
return SCryptFunction.getInstance(workFactor, resources, parallelization);
int derivedKeyLength = PropertyReader.readInt("hash.scrypt.derivedKeyLength", SCryptFunction.DERIVED_KEY_LENGTH, "SCrypt derivedKeyLength (dkLen) is not defined");
return SCryptFunction.getInstance(workFactor, resources, parallelization, derivedKeyLength);
}

public static MessageDigestFunction getMessageDigestInstance()
Expand Down
72 changes: 49 additions & 23 deletions src/main/java/com/password4j/SCryptFunction.java
View file
Original file line number Diff line number Diff line change
Expand Up @@ -33,13 +33,16 @@
*/
public class SCryptFunction extends AbstractHashingFunction
{
public static final int DERIVED_KEY_LENGTH = 64;

private int workFactor; // N

private int resources; // r

private int parallelization; // p

private int derivedKeyLength; // dkLen

private static final ConcurrentMap<String, SCryptFunction> INSTANCES = new ConcurrentHashMap<>();

@SuppressWarnings("unused")
Expand All @@ -58,6 +61,21 @@ protected SCryptFunction(int workFactor, int resources, int parallelization)
this.resources = resources;
this.workFactor = workFactor;
this.parallelization = parallelization;
this.derivedKeyLength = DERIVED_KEY_LENGTH;
}

/**
* @param workFactor (N)
* @param resources (r)
* @param parallelization (p)
* @param derivedKeyLength (dkLen)
*/
protected SCryptFunction(int workFactor, int resources, int parallelization, int derivedKeyLength)
{
this.resources = resources;
this.workFactor = workFactor;
this.parallelization = parallelization;
this.derivedKeyLength = derivedKeyLength;
}

/**
Expand All @@ -77,8 +95,9 @@ public static SCryptFunction getInstanceFromHash(String hashed)
int workFactor = (int) Math.pow(2.0D, (double) (params >> 16 & 65535L));
int resources = (int) params >> 8 & 255;
int parallelization = (int) params & 255;
int derivedKeyLength = Base64.getDecoder().decode(parts[4]).length;

return SCryptFunction.getInstance(workFactor, resources, parallelization);
return SCryptFunction.getInstance(workFactor, resources, parallelization, derivedKeyLength);
}
throw new BadParametersException("`" + hashed + "` is not a valid hash");
}
Expand All @@ -95,14 +114,30 @@ public static SCryptFunction getInstanceFromHash(String hashed)
*/
public static SCryptFunction getInstance(int workFactor, int resources, int parallelization)
{
String key = getUID(resources, workFactor, parallelization);
return getInstance(workFactor, resources, parallelization, DERIVED_KEY_LENGTH);
}

/**
* Creates a singleton instance, depending on the provided
* N, r and p parameters.
*
* @param workFactor work factor (N)
* @param resources resources (r)
* @param parallelization parallelization (p)
* @param derivedKeyLength derived key length (dkLen)
* @return a singleton instance
* @since 0.3.0
*/
public static SCryptFunction getInstance(int workFactor, int resources, int parallelization, int derivedKeyLength)
{
String key = getUID(resources, workFactor, parallelization, derivedKeyLength);
if (INSTANCES.containsKey(key))
{
return INSTANCES.get(key);
}
else
{
SCryptFunction function = new SCryptFunction(workFactor, resources, parallelization);
SCryptFunction function = new SCryptFunction(workFactor, resources, parallelization, derivedKeyLength);
INSTANCES.put(key, function);
return function;
}
Expand All @@ -121,7 +156,7 @@ public Hash hash(CharSequence plainTextPassword, String salt)
try
{
byte[] saltAsBytes = Utils.fromCharSequenceToBytes(salt);
byte[] derived = scrypt(Utils.fromCharSequenceToBytes(plainTextPassword), saltAsBytes, 64);
byte[] derived = scrypt(Utils.fromCharSequenceToBytes(plainTextPassword), saltAsBytes, derivedKeyLength);
String params = Long.toString((long) Utils.log2(workFactor) << 16 | (long) resources << 8 | parallelization, 16);
String sb = "$s0$" + params + '$' + Base64.getEncoder().encodeToString(saltAsBytes) + '$' + Base64.getEncoder()
.encodeToString(derived);
Expand All @@ -144,22 +179,8 @@ public boolean check(CharSequence plainTextPassword, String hashed)
{
byte[] salt = Base64.getDecoder().decode(parts[3]);
byte[] derived0 = Base64.getDecoder().decode(parts[4]);
byte[] derived1 = scrypt(Utils.fromCharSequenceToBytes(plainTextPassword), salt, 64);
if (derived0.length != derived1.length)
{
return false;
}
else
{
int result = 0;

for (int i = 0; i < derived0.length; ++i)
{
result |= derived0[i] ^ derived1[i];
}

return result == 0;
}
byte[] derived1 = scrypt(Utils.fromCharSequenceToBytes(plainTextPassword), salt, derivedKeyLength);
return slowEquals(derived0, derived1);
}
else
{
Expand Down Expand Up @@ -199,6 +220,11 @@ public int getParallelization()
return parallelization;
}

public int getDerivedKeyLength()
{
return derivedKeyLength;
}

/**
* A more readable version of {@link #getRequiredBytes()},
* changing the unit (B, KB, MB) so that the number has at most
Expand Down Expand Up @@ -238,7 +264,7 @@ public boolean equals(Object obj)
@Override
public String toString()
{
return getClass().getSimpleName() + '[' + getUID(this.resources, this.workFactor, this.parallelization) + ']';
return getClass().getSimpleName() + '[' + getUID(this.resources, this.workFactor, this.parallelization, this.derivedKeyLength) + ']';
}

@Override
Expand All @@ -247,9 +273,9 @@ public int hashCode()
return Objects.hash(resources, workFactor, parallelization);
}

protected static String getUID(int resources, int workFactor, int parallelization)
protected static String getUID(int resources, int workFactor, int parallelization, int derivedKeyLength)
{
return workFactor + "|" + resources + "|" + parallelization;
return workFactor + "|" + resources + "|" + parallelization + "|" + derivedKeyLength;
}


Expand Down
24 changes: 24 additions & 0 deletions src/test/com/password4j/PasswordTest.java
View file
Original file line number Diff line number Diff line change
Expand Up @@ -704,6 +704,30 @@ public void testGenericUpdate5()

}

@Test
public void testBCryptNonStandardParams()
{
final String testHash = "$2b$16$.1FczuSNl2iXHmLojhwBZO9vCfA5HIqrONkefhvn2qLQpth3r7Jwe";
Assert.assertTrue(Password.check("s$cret12", testHash).with(BCryptFunction.getInstanceFromHash(testHash)));
}

@Test
public void testSCryptNonStandardParams()
{
/*
* This password hash was generated using com.lambdaworks:scrypt, which has a derived key length (dkLen) of 32 bytes.
*/
final String testHash = "$s0$e0801$fl+gNAicpGG4gLMkUTCvLw==$N5wE1IKsr4LPBoetJVW6jLzEH4kTVXuKGafvAA8Z+88=";
Assert.assertTrue(Password.check("Hello world!", testHash).with(SCryptFunction.getInstanceFromHash(testHash)));
}

@Test
public void testArgon2NonstandardParams()
{
/*
* This password hash comes from the Argon2 C reference implementation (https://github.com/P-H-C/phc-winner-argon2).
*/
final String testHash = "$argon2i$v=19$m=65536,t=2,p=4$c29tZXNhbHQ$RdescudvJCsgt3ub+b+dWRWJTmaaJObG";
Assert.assertTrue(Password.check("password", testHash).with(Argon2Function.getInstanceFromHash(testHash)));
}
}
6 changes: 4 additions & 2 deletions src/test/com/password4j/SCryptFunctionTest.java
View file
Original file line number Diff line number Diff line change
Expand Up @@ -201,15 +201,17 @@ public void testAccessors()
int workFactor = 3;
int resources = 5;
int parallelization = 7;
int derivedKeyLength = 32;

// WHEN
SCryptFunction scrypt = SCryptFunction.getInstance(workFactor, resources,parallelization);
SCryptFunction scrypt = SCryptFunction.getInstance(workFactor, resources, parallelization, derivedKeyLength);

// THEN
Assert.assertEquals(workFactor, scrypt.getWorkFactor());
Assert.assertEquals(resources, scrypt.getResources());
Assert.assertEquals(parallelization, scrypt.getParallelization());
Assert.assertEquals("SCryptFunction[3|5|7]", scrypt.toString());
Assert.assertEquals(derivedKeyLength, scrypt.getDerivedKeyLength());
Assert.assertEquals("SCryptFunction[3|5|7|32]", scrypt.toString());
}

}

0 comments on commit c52c438

Please sign in to comment.