Require minetest.request_http_api to be called from the mod's main scope

Fixes #3764
This commit is contained in:
Jeija 2016-02-25 10:22:54 +01:00 committed by est31
parent 7bcbc0105b
commit 1100a5d614
2 changed files with 20 additions and 3 deletions

@ -2337,7 +2337,7 @@ These functions return the leftover itemstack.
otherwise returns `nil`.
* The returned table contains the functions `fetch`, `fetch_async` and `fetch_async_get`
described below.
* Only works at init time.
* Only works at init time and must be called from the mod's main scope (not from a function).
* Function only exists if minetest server was built with cURL support.
* **DO NOT ALLOW ANY OTHER MODS TO ACCESS THE RETURNED TABLE, STORE IT IN
A LOCAL VARIABLE!**

@ -23,6 +23,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
#include "lua_api/l_http.h"
#include "httpfetch.h"
#include "settings.h"
#include "debug.h"
#include "log.h"
#include <algorithm>
@ -130,11 +131,27 @@ int ModApiHttp::l_request_http_api(lua_State *L)
{
NO_MAP_LOCK_REQUIRED;
// We have to make sure that this function is being called directly by
// a mod, otherwise a malicious mod could override this function and
// steal its return value.
lua_Debug info;
// Make sure there's only one item below this function on the stack...
if (lua_getstack(L, 2, &info)) {
return 0;
}
FATAL_ERROR_IF(!lua_getstack(L, 1, &info), "lua_getstack() failed");
FATAL_ERROR_IF(!lua_getinfo(L, "S", &info), "lua_getinfo() failed");
// ...and that that item is the main file scope.
if (strcmp(info.what, "main") != 0) {
return 0;
}
// Mod must be listed in secure.http_mods or secure.trusted_mods
lua_rawgeti(L, LUA_REGISTRYINDEX, CUSTOM_RIDX_CURRENT_MOD_NAME);
if (!lua_isstring(L, -1)) {
lua_pushnil(L);
return 1;
return 0;
}
const char *mod_name = lua_tostring(L, -1);