lunatic: more sandboxing mechanisms, makefile lines for OSX

git-svn-id: https://svn.eduke32.com/eduke32@2074 1a8010ca-5511-0410-912e-c29ae57300e0

polymer/eduke32/Makefile

@@ -139,7 +139,15 @@ ifneq (0,$(LUNATIC))
     OURCFLAGS+= -I/usr/local/include/luajit-2.0 -I$(SRC)/lunatic -DLUNATIC_ENABLE
     LIBS+= -L/usr/local/lib -lluajit-5.1
     GAMEOBJS+= $(OBJ)/lunatic.$o
-    MISCLINKOPTS+= -Wl,--dynamic-list=$(SRC)/lunatic/dynsymlist
+    # strip on OSX says: removing global symbols from a final linked no longer supported.
+    #                    Use -exported_symbols_list at link time when building
+    # But, not doing this does not give us the symbols! wtf?
+    STRIP+= -s $(SRC)/lunatic/dynsymlist_osx
+    ifeq ($(PLATFORM),DARWIN)
+        MISCLINKOPTS+= -pagezero_size 10000 -image_base 100000000 #-Wl,-alias_list -Wl,$(SRC)/lunatic/aliases_list #-exported_symbols_list $(SRC)/lunatic/dynsymlist_osx
+    else
+        MISCLINKOPTS+= -Wl,--dynamic-list=$(SRC)/lunatic/dynsymlist
+    endif
 endif
 
 # PLATFORM SPECIFIC SETTINGS
@@ -307,6 +315,12 @@ $(OBJ)/%.$o: $(SRC)/lunatic/%.c
 	$(COMPILE_STATUS)
 	if $(CC) $(CFLAGS) $(OURCFLAGS) -c $< -o $@; then $(COMPILE_OK); else $(COMPILE_FAILED); fi
 
+$(SRC)/lunatic/dynsymlist_osx: $(SRC)/lunatic/dynsymlist
+	sed 's/[{};]//g;s/[A-Za-z_][A-Za-z_0-9]*/_&/g' $< > $@
+
+$(SRC)/lunatic/aliases_list: $(SRC)/lunatic/dynsymlist_osx
+	sed 's/_\([A-Za-z_][A-Za-z_0-9]*\)/_\1 \1/g' $< > $@
+
 $(OBJ)/%.$o: Apple/%.m
 	$(COMPILE_STATUS)
 	if $(CC) $(CFLAGS) $(OURCFLAGS) -c $< -o $@; then $(COMPILE_OK); else $(COMPILE_FAILED); fi

polymer/eduke32/source/lunatic/defs.ilua

@@ -58,7 +58,56 @@ const int16_t prevspritesect[16384], prevspritestat[16384];
 const int16_t nextspritesect[16384], nextspritestat[16384];
 ]]
 
---
+---- _G tweaks -- pull in only 'safe' stuff ----
+
+local G_ = {}  -- our soon-to-be global environment
+local oG = _G
+
+G_.coroutine = coroutine
+G_.assert = assert
+G_.tostring = tostring
+G_.tonumber = tonumber
+--rawget
+G_.xpcall = xpcall
+G_.ipairs = ipairs
+G_.print = print
+G_.pcall = pcall
+--gcinfo --DEPRECATED
+--module
+--setfenv
+--require
+--rawset
+--jit
+G_.bit = bit
+--package
+G_.error = error
+--debug
+--loadfile
+--rawequal
+--load
+G_.unpack = unpack
+G_.pairs = pairs
+G_.table = table
+G_._VERSION = _VERSION
+--newproxy --NOT STD?
+--collectgarbage
+--dofile
+G_.next = next
+G_.math = math
+--loadstring
+--_G
+G_.select = select
+G_.string = string
+G_.type = type
+--getmetatable
+--getfenv
+--setmetatable
+
+G_._G = G_
+
+-- REMOVE this for release
+DBG_ = {}
+DBG_.loadstring = oG.loadstring
 
 ---- Set up restricted access to ffi.C from lunatic. ----
 local ffiC = ffi.C
@@ -69,7 +118,7 @@ local tmpmt = {
     __newindex = function() error('dummy variable: write access forbidden') end,
     __metatable = true  -- forbid setting the metatable
 }
-setmetatable(det, tmpmt)
+oG.setmetatable(det, tmpmt)
 
 -- GLOBAL gv: provides access to C global *scalars*
 gv = {
@@ -89,7 +138,7 @@ local tmpmt = {
     __newindex = function() error("cannot create new fields in 'gv'") end,
     __metatable = true,
 }
-setmetatable(gv, tmpmt)
+oG.setmetatable(gv, tmpmt)
 
 ---- indirect C array access ----
 sector = {}
@@ -102,7 +151,7 @@ local tmpmt = {
     __newindex = function(tab, key, val) error('cannot write to sector[] struct directly') end,
     __metatable = true,
 }
-setmetatable(sector, tmpmt)
+oG.setmetatable(sector, tmpmt)
 
 wall = {}
 local tmpmt = {
@@ -114,7 +163,7 @@ local tmpmt = {
     __newindex = function(tab, key, val) error('cannot write to wall[] struct directly') end,
     __metatable = true,
 }
-setmetatable(wall, tmpmt)
+oG.setmetatable(wall, tmpmt)
 
 -- create a safe indirection for a ffi.C array
 local function creategtab(ctab, maxidx, name)
@@ -131,7 +180,7 @@ local function creategtab(ctab, maxidx, name)
                      end,
         __metatable = true,
     }
-    setmetatable(tab, tmpmt)
+    oG.setmetatable(tab, tmpmt)
     return tab
 end
 
@@ -176,6 +225,21 @@ function spritesofstat(stat)
     return iter_spritesofstat , stat, -1
 end
 
--- restrict access to potentially unsafe standard Lua modules (not yet done)
-os = nil
-io = nil
+
+-- add new variables/functions living in the global environment
+G_.DBG_ = DBG_  -- REMOVE this for release
+G_.gv = gv
+G_.sector = sector
+G_.wall = wall
+G_.sprite = sprite
+G_.headspritesect = headspritesect
+G_.headspritestat = headspritestat
+G_.nextspritesect = nextspritesect
+G_.nextspritestat = nextspritestat
+G_.prevspritesect = prevspritesect
+G_.prevspritestat = prevspritestat
+G_.spritesofsect = spritesofsect
+G_.spritesofstat = spritesofstat
+
+-- change the environment of the running Lua thread to the table G_
+setfenv(0, G_)

polymer/eduke32/source/lunatic/dynsymlist

@@ -6,7 +6,10 @@ sprite;
 numsectors;
 numwalls;
 
-headspritesect; headspritestat;
-prevspritesect; prevspritestat;
-nextspritesect; nextspritestat;
+headspritesect;
+headspritestat;
+prevspritesect;
+prevspritestat;
+nextspritesect;
+nextspritestat;
 };

polymer/eduke32/source/lunatic/lunatic.c

@@ -25,7 +25,7 @@ int32_t El_CreateState(El_State *estate, const char *name)
     {
         Bfree((char *)estate->name);
         estate->name = NULL;
-        return -1;
+        return -2;
     }
 
     luaL_openlibs(estate->L);  // XXX: only for internal use and testing, obviously

polymer/eduke32/source/lunatic/test.elua

@@ -3,7 +3,7 @@
 print('--- ELua Test script ---')
 
 local function checkfail(funcstr)
-    local status, res = pcall(loadstring(funcstr))
+    local status, res = pcall(DBG_.loadstring(funcstr))
     if (status) then
         print('ERROR: '..funcstr.." DIDN'T fail")
     else
@@ -14,6 +14,7 @@ end
 local i
 
 print('tweaking sector pals')
+---[[
 for i = 0, gv.numsectors/2 do
     sector[i].floorpal = 1;
     sector[i].ceilingpal = 2;
@@ -28,7 +29,7 @@ end
 for spr in spritesofsect(236) do
     print('#spr', spr)
 end
-
+--]]
 print('_G contains:')
 for k,v in pairs(_G) do
     print(k, v)
@@ -40,9 +41,7 @@ checkfail('sector[-1].ceilingpal = 4')  -- oob write access
 checkfail('sector[0].wallnum = 0')  -- wallnum member is read-only
 checkfail('gv.numsectors = 4')  -- gv.numsectors is read-only
 checkfail('sector[4] = sector[6]')  -- direct sector write access forbidden
-
+checkfail("require('os')")  -- 'require' has been thrown away to be replaced by
+                            -- something more restricted later
 
 print('--- end test script ---')
-
-os = require("os")
-print('clk', os.clock())