From 8fbc7e0d2c3c807760f2a0fdf48c5ba68f7772f4 Mon Sep 17 00:00:00 2001 From: Rob Winch Date: Thu, 3 Mar 2016 14:18:50 -0600 Subject: [PATCH] Fix SCryptPasswordEncoder javadoc Issue gh-3702 --- .../crypto/scrypt/SCryptPasswordEncoder.java | 47 ++++++++++++------- 1 file changed, 30 insertions(+), 17 deletions(-) diff --git a/crypto/src/main/java/org/springframework/security/crypto/scrypt/SCryptPasswordEncoder.java b/crypto/src/main/java/org/springframework/security/crypto/scrypt/SCryptPasswordEncoder.java index dd505cd0fe..293a4435f5 100644 --- a/crypto/src/main/java/org/springframework/security/crypto/scrypt/SCryptPasswordEncoder.java +++ b/crypto/src/main/java/org/springframework/security/crypto/scrypt/SCryptPasswordEncoder.java @@ -24,14 +24,12 @@ import org.springframework.security.crypto.keygen.BytesKeyGenerator; import org.springframework.security.crypto.keygen.KeyGenerators; import org.springframework.security.crypto.password.PasswordEncoder; - - /** *

* Implementation of PasswordEncoder that uses the SCrypt hashing function. * Clients can optionally supply a cpu cost parameter, a memory cost parameter * and a parallelization parameter. - *

+ *

* *

* A few *

  • Scrypt is based on Salsa20 which performs poorly in Java (on par with * AES) but performs awesome (~4-5x faster) on SIMD capable platforms
    • - *
  • While there are some that would disagree, consider reading "Why I Don't Recommend Scrypt (for password storage)"
    • + *
  • While there are some that would disagree, consider reading - + * + * Why I Don't Recommend Scrypt (for password storage)
    • * * * @author Shazin Sadakath @@ -75,11 +73,24 @@ public class SCryptPasswordEncoder implements PasswordEncoder { /** * Creates a new instance * - * @param cpuCost cpu cost of the algorithm (as defined in scrypt this is N). must be power of 2 greater than 1. Default is currently 16,348 or 2^14) - * @param memoryCost memory cost of the algorithm (as defined in scrypt this is r) Default is currently 8. - * @param parallelization the parallelization of the algorithm (as defined in scrypt this is p) Default is currently 1. Note that the implementation does not currently take advantage of parallelization. - * @param key length for the algorithm (as defined in scrypt this is dkLen). The default is currently 32. - * @param salt length (as defined in scrypt this is the length of S). The default is currently 64. + * @param cpuCost + * cpu cost of the algorithm (as defined in scrypt this is N). + * must be power of 2 greater than 1. Default is currently 16,348 + * or 2^14) + * @param memoryCost + * memory cost of the algorithm (as defined in scrypt this is r) + * Default is currently 8. + * @param parallelization + * the parallelization of the algorithm (as defined in scrypt + * this is p) Default is currently 1. Note that the + * implementation does not currently take advantage of + * parallelization. + * @param keyLength + * key length for the algorithm (as defined in scrypt this is + * dkLen). The default is currently 32. + * @param saltLength + * salt length (as defined in scrypt this is the length of S). + * The default is currently 64. */ public SCryptPasswordEncoder(int cpuCost, int memoryCost, int parallelization, int keyLength, int saltLength) { if (cpuCost <= 1) { @@ -94,13 +105,13 @@ public class SCryptPasswordEncoder implements PasswordEncoder { int maxParallel = Integer.MAX_VALUE / (128 * memoryCost * 8); if (parallelization < 1 || parallelization > maxParallel) { throw new IllegalArgumentException("Parallelisation parameter p must be >= 1 and <= " + maxParallel - + " (based on block size r of " + memoryCost + ")"); + + " (based on block size r of " + memoryCost + ")"); } if (keyLength < 1 || keyLength > Integer.MAX_VALUE) { - throw new IllegalArgumentException("Key length must be >= 1 and <= "+Integer.MAX_VALUE); + throw new IllegalArgumentException("Key length must be >= 1 and <= " + Integer.MAX_VALUE); } if (saltLength < 1 || saltLength > Integer.MAX_VALUE) { - throw new IllegalArgumentException("Salt length must be >= 1 and <= "+Integer.MAX_VALUE); + throw new IllegalArgumentException("Salt length must be >= 1 and <= " + Integer.MAX_VALUE); } this.cpuCost = cpuCost; @@ -115,7 +126,7 @@ public class SCryptPasswordEncoder implements PasswordEncoder { } public boolean matches(CharSequence rawPassword, String encodedPassword) { - if(encodedPassword == null || encodedPassword.length() < keyLength) { + if (encodedPassword == null || encodedPassword.length() < keyLength) { logger.warn("Empty encoded password"); return false; } @@ -137,7 +148,8 @@ public class SCryptPasswordEncoder implements PasswordEncoder { int memoryCost = (int) params >> 8 & 0xff; int parallelization = (int) params & 0xff; - byte[] generated = SCrypt.generate(Utf8.encode(rawPassword), salt, cpuCost, memoryCost, parallelization, keyLength); + byte[] generated = SCrypt.generate(Utf8.encode(rawPassword), salt, cpuCost, memoryCost, parallelization, + keyLength); if (derived.length != generated.length) { return false; @@ -153,7 +165,8 @@ public class SCryptPasswordEncoder implements PasswordEncoder { private String digest(CharSequence rawPassword, byte[] salt) { byte[] derived = SCrypt.generate(Utf8.encode(rawPassword), salt, cpuCost, memoryCost, parallelization, 32); - String params = Long.toString(((int) (Math.log(cpuCost) / Math.log(2)) << 16L) | memoryCost << 8 | parallelization, 16); + String params = Long + .toString(((int) (Math.log(cpuCost) / Math.log(2)) << 16L) | memoryCost << 8 | parallelization, 16); StringBuilder sb = new StringBuilder((salt.length + derived.length) * 2); sb.append("$").append(params).append('$');