#include <sys/types.h>
#include <sys/sysctl.h>
#elif defined(_WIN32)
+ #include <windows.h>
+ #include <wincrypt.h>
#include <algorithm>
#endif
#if !defined(_WIN32)
# endif // __ANDROID__
#endif // SERVER
-} //namespace porting
+////
+//// OS-specific Secure Random
+////
+
+#ifdef WIN32
+
+bool secure_rand_fill_buf(void *buf, size_t len)
+{
+ HCRYPTPROV wctx;
+
+ if (!CryptAcquireContext(&wctx, NULL, NULL, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT))
+ return false;
+
+ CryptGenRandom(wctx, len, (BYTE *)buf);
+ CryptReleaseContext(wctx, 0);
+ return true;
+}
+
+#else
+
+bool secure_rand_fill_buf(void *buf, size_t len)
+{
+ // N.B. This function checks *only* for /dev/urandom, because on most
+ // common OSes it is non-blocking, whereas /dev/random is blocking, and it
+ // is exceptionally uncommon for there to be a situation where /dev/random
+ // exists but /dev/urandom does not. This guesswork is necessary since
+ // random devices are not covered by any POSIX standard...
+ FILE *fp = fopen("/dev/urandom", "rb");
+ if (!fp)
+ return false;
+
+ bool success = fread(buf, len, 1, fp) == 1;
+
+ fclose(fp);
+ return success;
+}
+
+#endif
+
+} //namespace porting
#include "common/c_converter.h"
#include "common/c_content.h"
#include "log.h"
+#include "porting.h"
+#include "util/numeric.h"
///////////////////////////////////////
/*
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}
+};