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util-src/windows.c @ 12181:783056b4e448 0.11 0.11.12
util.xml: Do not allow doctypes, comments or processing instructions
Yes. This is as bad as it sounds. CVE pending.
In Prosody itself, this only affects mod_websocket, which uses util.xml
to parse the <open/> frame, thus allowing unauthenticated remote DoS
using Billion Laughs. However, third-party modules using util.xml may
also be affected by this.
This commit installs handlers which disallow the use of doctype
declarations and processing instructions without any escape hatch. It,
by default, also introduces such a handler for comments, however, there
is a way to enable comments nontheless.
This is because util.xml is used to parse human-facing data, where
comments are generally a desirable feature, and also because comments
are generally harmless.
author | Jonas Schäfer <jonas@wielicki.name> |
---|---|
date | Mon, 10 Jan 2022 18:23:54 +0100 |
parent | 7889:b8d694646597 |
child | 10921:6eb5d2bb11af |
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/* Prosody IM -- Copyright (C) 2008-2010 Matthew Wild -- Copyright (C) 2008-2010 Waqas Hussain -- -- This project is MIT/X11 licensed. Please see the -- COPYING file in the source package for more information. -- */ /* * windows.c * Windows support functions for Lua */ #include <stdio.h> #include <windows.h> #include <windns.h> #include "lua.h" #include "lauxlib.h" #if (LUA_VERSION_NUM == 501) #define luaL_setfuncs(L, R, N) luaL_register(L, NULL, R) #endif static int Lget_nameservers(lua_State *L) { char stack_buffer[1024]; // stack allocated buffer IP4_ARRAY *ips = (IP4_ARRAY *) stack_buffer; DWORD len = sizeof(stack_buffer); DNS_STATUS status; status = DnsQueryConfig(DnsConfigDnsServerList, FALSE, NULL, NULL, ips, &len); if(status == 0) { DWORD i; lua_createtable(L, ips->AddrCount, 0); for(i = 0; i < ips->AddrCount; i++) { DWORD ip = ips->AddrArray[i]; char ip_str[16] = ""; sprintf_s(ip_str, sizeof(ip_str), "%d.%d.%d.%d", (ip >> 0) & 255, (ip >> 8) & 255, (ip >> 16) & 255, (ip >> 24) & 255); lua_pushstring(L, ip_str); lua_rawseti(L, -2, i + 1); } return 1; } else { lua_pushnil(L); lua_pushfstring(L, "DnsQueryConfig returned %d", status); return 2; } } static int lerror(lua_State *L, char *string) { lua_pushnil(L); lua_pushfstring(L, "%s: %d", string, GetLastError()); return 2; } static int Lget_consolecolor(lua_State *L) { HWND console = GetStdHandle(STD_OUTPUT_HANDLE); WORD color; DWORD read_len; CONSOLE_SCREEN_BUFFER_INFO info; if(console == INVALID_HANDLE_VALUE) { return lerror(L, "GetStdHandle"); } if(!GetConsoleScreenBufferInfo(console, &info)) { return lerror(L, "GetConsoleScreenBufferInfo"); } if(!ReadConsoleOutputAttribute(console, &color, 1, info.dwCursorPosition, &read_len)) { return lerror(L, "ReadConsoleOutputAttribute"); } lua_pushnumber(L, color); return 1; } static int Lset_consolecolor(lua_State *L) { int color = luaL_checkint(L, 1); HWND console = GetStdHandle(STD_OUTPUT_HANDLE); if(console == INVALID_HANDLE_VALUE) { return lerror(L, "GetStdHandle"); } if(!SetConsoleTextAttribute(console, color)) { return lerror(L, "SetConsoleTextAttribute"); } lua_pushboolean(L, 1); return 1; } static const luaL_Reg Reg[] = { { "get_nameservers", Lget_nameservers }, { "get_consolecolor", Lget_consolecolor }, { "set_consolecolor", Lset_consolecolor }, { NULL, NULL } }; LUALIB_API int luaopen_util_windows(lua_State *L) { #if (LUA_VERSION_NUM > 501) luaL_checkversion(L); #endif lua_newtable(L); luaL_setfuncs(L, Reg, 0); lua_pushliteral(L, "-3.14"); lua_setfield(L, -2, "version"); return 1; }