Add function bcrypt_needs_rehash

The function can be used to check whether or not a given hash is valid,
and maches a given cost.

bcrypt.inc

@@ -1,5 +1,5 @@
 /* The MIT License (MIT)
- * Copyright (c) 2013 Lassi R.
+ * Copyright (c) 2014 Lassi R.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy of 
  * this software and associated documentation files (the "Software"), to deal in 
@@ -26,9 +26,11 @@
 #define bcrypt_included
 
 #define BCRYPT_HASH_LENGTH 61
+#define BCRYPT_PLUGIN_VERSION "2.2"
 
 native bcrypt_hash(key[], cost = 12, callback_name[], callback_format[] = "", {Float, _}:...);
 native bcrypt_check(password[], hash[], callback_name[], callback_format[] = "", {Float, _}:...);
 native bcrypt_get_hash(dest[]);
 native bool:bcrypt_is_equal();
+native bool:bcrypt_needs_rehash(hash[], cost);
 native bcrypt_set_thread_limit(value);

src/main.cpp

@@ -9,6 +9,7 @@ AMX_NATIVE_INFO PluginNatives [] =
 	DEFINE_NATIVE(bcrypt_check)
 	DEFINE_NATIVE(bcrypt_get_hash)
 	DEFINE_NATIVE(bcrypt_is_equal)
+	DEFINE_NATIVE(bcrypt_needs_rehash)
 	DEFINE_NATIVE(bcrypt_set_thread_limit)
 	{ 0, 0 }
 };

src/main.h

@@ -4,6 +4,6 @@
 #include "SDK/amx/amx.h"
 #include "SDK/plugincommon.h"
 
-#define BCRYPT_VERSION "v2.1.2"
+#define BCRYPT_VERSION "v2.2"
 
 #endif

src/natives.cpp

@@ -1,4 +1,5 @@
 #include <thread>
+#include <cstring>
 
 #include "plugin.h"
 #include "natives.h"
@@ -96,6 +97,30 @@ DECLARE_NATIVE(native::bcrypt_is_equal)
 	return (int)plugin::get()->get_active_match();
 }
 
+// native bool:bcrypt_needs_rehash(hash[], cost);
+DECLARE_NATIVE(native::bcrypt_needs_rehash)
+{
+	if (params[0] != sizeof(cell) * 2)
+	{
+		plugin::printf("plugin.bcrypt: bcrypt_needs_rehash: Invalid number of parameters (2 expected)");
+	}
+
+	char *hash = NULL;
+	unsigned expected_cost;
+
+	amx_StrParam(amx, params[1], hash);
+	expected_cost = static_cast<unsigned>(params[2]);
+
+	if (hash[0] != '$' || hash[1] != '2' || hash[2] != 'y' || hash[3] != '$' || hash[6] != '$' || strlen(hash) != 60)
+		return 1;
+
+	unsigned cost = (hash[4] - '0') * 10 + (hash[5] - '0');
+	if (cost != expected_cost)
+		return 1;
+
+	return 0;
+}
+
 // native bcrypt_set_thread_limit(value);
 DECLARE_NATIVE(native::bcrypt_set_thread_limit)
 {

src/natives.h

@@ -17,6 +17,7 @@ namespace native
 	DECLARE_NATIVE(bcrypt_get_hash);
 	DECLARE_NATIVE(bcrypt_check);
 	DECLARE_NATIVE(bcrypt_is_equal);
+	DECLARE_NATIVE(bcrypt_needs_rehash);
 	DECLARE_NATIVE(bcrypt_set_thread_limit);
 }