1 files changed, 123 insertions, 3 deletions

diff --git a/src/script/lua_api/l_noise.cpp b/src/script/lua_api/l_noise.cpp
index c8dc2d2dc..04dc6048f 100644
--- a/src/script/lua_api/l_noise.cpp
+++ b/src/script/lua_api/l_noise.cpp
@@ -22,6 +22,8 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "common/c_converter.h"
 #include "common/c_content.h"
 #include "log.h"
+#include "porting.h"
+#include "util/numeric.h"
 
 ///////////////////////////////////////
 /*
@@ -410,6 +412,7 @@ const luaL_reg LuaPerlinNoiseMap::methods[] = {
 int LuaPseudoRandom::l_next(lua_State *L)
 {
 	NO_MAP_LOCK_REQUIRED;
+
 	LuaPseudoRandom *o = checkobject(L, 1);
 	int min = 0;
 	int max = 32767;
@@ -437,7 +440,9 @@ int LuaPseudoRandom::l_next(lua_State *L)
 
 int LuaPseudoRandom::create_object(lua_State *L)
 {
-	int seed = luaL_checknumber(L, 1);
+	NO_MAP_LOCK_REQUIRED;
+
+	u64 seed = luaL_checknumber(L, 1);
 	LuaPseudoRandom *o = new LuaPseudoRandom(seed);
 	*(void **)(lua_newuserdata(L, sizeof(void *))) = o;
 	luaL_getmetatable(L, className);
@@ -532,8 +537,10 @@ int LuaPcgRandom::l_rand_normal_dist(lua_State *L)
 
 int LuaPcgRandom::create_object(lua_State *L)
 {
-	lua_Integer seed = luaL_checknumber(L, 1);
-	LuaPcgRandom *o  = lua_isnumber(L, 2) ?
+	NO_MAP_LOCK_REQUIRED;
+
+	u64 seed = luaL_checknumber(L, 1);
+	LuaPcgRandom *o = lua_isnumber(L, 2) ?
 		new LuaPcgRandom(seed, lua_tointeger(L, 2)) :
 		new LuaPcgRandom(seed);
 	*(void **)(lua_newuserdata(L, sizeof(void *))) = o;
@@ -595,3 +602,116 @@ const luaL_reg LuaPcgRandom::methods[] = {
 	luamethod(LuaPcgRandom, rand_normal_dist),
 	{0,0}
 };
+
+///////////////////////////////////////
+/*
+	LuaSecureRandom
+*/
+
+bool LuaSecureRandom::fillRandBuf()
+{
+	return porting::secure_rand_fill_buf(m_rand_buf, RAND_BUF_SIZE);
+}
+
+int LuaSecureRandom::l_next_bytes(lua_State *L)
+{
+	NO_MAP_LOCK_REQUIRED;
+
+	LuaSecureRandom *o = checkobject(L, 1);
+	u32 count = lua_isnumber(L, 2) ? lua_tointeger(L, 2) : 1;
+
+	// Limit count
+	count = MYMIN(RAND_BUF_SIZE, count);
+
+	// Find out whether we can pass directly from our array, or have to do some gluing
+	size_t count_remaining = RAND_BUF_SIZE - o->m_rand_idx;
+	if (count_remaining >= count) {
+		lua_pushlstring(L, o->m_rand_buf + o->m_rand_idx, count);
+		o->m_rand_idx += count;
+	} else {
+		char output_buf[RAND_BUF_SIZE];
+
+		// Copy over with what we have left from our current buffer
+		memcpy(output_buf, o->m_rand_buf + o->m_rand_idx, count_remaining);
+
+		// Refill buffer and copy over the remainder of what was requested
+		o->fillRandBuf();
+		memcpy(output_buf + count_remaining, o->m_rand_buf, count - count_remaining);
+
+		// Update index
+		o->m_rand_idx = count - count_remaining;
+
+		lua_pushlstring(L, output_buf, count);
+	}
+
+	return 1;
+}
+
+
+int LuaSecureRandom::create_object(lua_State *L)
+{
+	LuaSecureRandom *o = new LuaSecureRandom();
+
+	// Fail and return nil if we can't securely fill the buffer
+	if (!o->fillRandBuf()) {
+		delete o;
+		return 0;
+	}
+
+	*(void **)(lua_newuserdata(L, sizeof(void *))) = o;
+	luaL_getmetatable(L, className);
+	lua_setmetatable(L, -2);
+	return 1;
+}
+
+
+int LuaSecureRandom::gc_object(lua_State *L)
+{
+	LuaSecureRandom *o = *(LuaSecureRandom **)(lua_touserdata(L, 1));
+	delete o;
+	return 0;
+}
+
+
+LuaSecureRandom *LuaSecureRandom::checkobject(lua_State *L, int narg)
+{
+	luaL_checktype(L, narg, LUA_TUSERDATA);
+	void *ud = luaL_checkudata(L, narg, className);
+	if (!ud)
+		luaL_typerror(L, narg, className);
+	return *(LuaSecureRandom **)ud;
+}
+
+
+void LuaSecureRandom::Register(lua_State *L)
+{
+	lua_newtable(L);
+	int methodtable = lua_gettop(L);
+	luaL_newmetatable(L, className);
+	int metatable = lua_gettop(L);
+
+	lua_pushliteral(L, "__metatable");
+	lua_pushvalue(L, methodtable);
+	lua_settable(L, metatable);
+
+	lua_pushliteral(L, "__index");
+	lua_pushvalue(L, methodtable);
+	lua_settable(L, metatable);
+
+	lua_pushliteral(L, "__gc");
+	lua_pushcfunction(L, gc_object);
+	lua_settable(L, metatable);
+
+	lua_pop(L, 1);
+
+	luaL_openlib(L, 0, methods, 0);
+	lua_pop(L, 1);
+
+	lua_register(L, className, create_object);
+}
+
+const char LuaSecureRandom::className[] = "SecureRandom";
+const luaL_reg LuaSecureRandom::methods[] = {
+	luamethod(LuaSecureRandom, next_bytes),
+	{0,0}
+};