Add crypto provider to transition from wordpress user accounts

lib/authlogic/crypto_providers/wordpress.rb

@@ -0,0 +1,43 @@
+require 'digest/md5'
+module Authlogic
+  module CryptoProviders
+    class Wordpress
+      class << self
+        ITOA64 = './0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';
+
+        def matches?(crypted, *tokens)
+          stretches = 1 << ITOA64.index(crypted[3,1])
+          plain, salt = *tokens 
+          hashed = Digest::MD5.digest(salt+plain)
+          stretches.times do |i|
+            hashed = Digest::MD5.digest(hashed+plain)
+          end
+          crypted[0,12]+encode_64(hashed, 16) == crypted
+        end
+
+        def encode_64(input, length)
+          output = "" 
+          i = 0
+          while i < length
+            value = input[i] 
+            i+=1
+            break if value.nil?
+            output += ITOA64[value & 0x3f, 1]
+            value |= input[i] << 8 if i < length
+            output += ITOA64[(value >> 6) & 0x3f, 1]
+
+            i+=1
+            break if i >= length
+            value |= input[i] << 16 if i < length
+            output += ITOA64[(value >> 12) & 0x3f,1]
+
+            i+=1
+            break if i >= length
+            output += ITOA64[(value >> 18) & 0x3f,1]
+          end
+          output
+        end
+      end
+    end
+  end
+end