crypto: support custom pbkdf2 digest methods

Make the HMAC digest method configurable.  Update crypto.pbkdf2() and
crypto.pbkdf2Sync() to take an extra, optional digest argument.

Before this commit, SHA-1 (admittedly the most common method) was used
exclusively.

Fixes #6553.

1 files changed, 20 insertions, 9 deletions

diff --git a/lib/crypto.js b/lib/crypto.js
index 050d54afd1..8226241490 100644
--- a/lib/crypto.js
+++ b/lib/crypto.js
@@ -575,36 +575,47 @@ DiffieHellman.prototype.setPrivateKey = function(key, encoding) {
 
 
 
-exports.pbkdf2 = function(password, salt, iterations, keylen, callback) {
+exports.pbkdf2 = function(password,
+                          salt,
+                          iterations,
+                          keylen,
+                          digest,
+                          callback) {
+  if (util.isFunction(digest)) {
+    callback = digest;
+    digest = undefined;
+  }
+
   if (!util.isFunction(callback))
     throw new Error('No callback provided to pbkdf2');
 
-  return pbkdf2(password, salt, iterations, keylen, callback);
+  return pbkdf2(password, salt, iterations, keylen, digest, callback);
 };
 
 
-exports.pbkdf2Sync = function(password, salt, iterations, keylen) {
-  return pbkdf2(password, salt, iterations, keylen);
+exports.pbkdf2Sync = function(password, salt, iterations, keylen, digest) {
+  return pbkdf2(password, salt, iterations, keylen, digest);
 };
 
 
-function pbkdf2(password, salt, iterations, keylen, callback) {
+function pbkdf2(password, salt, iterations, keylen, digest, callback) {
   password = toBuf(password);
   salt = toBuf(salt);
 
   if (exports.DEFAULT_ENCODING === 'buffer')
-    return binding.PBKDF2(password, salt, iterations, keylen, callback);
+    return binding.PBKDF2(password, salt, iterations, keylen, digest, callback);
 
   // at this point, we need to handle encodings.
   var encoding = exports.DEFAULT_ENCODING;
   if (callback) {
-    binding.PBKDF2(password, salt, iterations, keylen, function(er, ret) {
+    function next(er, ret) {
       if (ret)
         ret = ret.toString(encoding);
       callback(er, ret);
-    });
+    }
+    binding.PBKDF2(password, salt, iterations, keylen, digest, next);
   } else {
-    var ret = binding.PBKDF2(password, salt, iterations, keylen);
+    var ret = binding.PBKDF2(password, salt, iterations, keylen, digest);
     return ret.toString(encoding);
   }
 }