Mercurial > prosody-hg
annotate util-src/compat.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 |
| parents | cfc7b2f7251e |
| children | a187600ec7d6 |
| rev | line source |
|---|---|
|
9561
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
1 |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
2 #include <lua.h> |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
3 #include <lauxlib.h> |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
4 |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
5 |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
6 static int lc_xpcall (lua_State *L) { |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
7 int ret; |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
8 int n_arg = lua_gettop(L); |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
9 /* f, msgh, p1, p2... */ |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
10 luaL_argcheck(L, n_arg >= 2, 2, "value expected"); |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
11 lua_pushvalue(L, 1); /* f to top */ |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
12 lua_pushvalue(L, 2); /* msgh to top */ |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
13 lua_replace(L, 1); /* msgh to 1 */ |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
14 lua_replace(L, 2); /* f to 2 */ |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
15 /* msgh, f, p1, p2... */ |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
16 ret = lua_pcall(L, n_arg - 2, LUA_MULTRET, 1); |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
17 lua_pushboolean(L, ret == 0); |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
18 lua_replace(L, 1); |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
19 return lua_gettop(L); |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
20 } |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
21 |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
22 int luaopen_util_compat(lua_State *L) { |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
23 lua_createtable(L, 0, 2); |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
24 { |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
25 lua_pushcfunction(L, lc_xpcall); |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
26 lua_setfield(L, -2, "xpcall"); |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
27 } |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
28 return 1; |
|
cfc7b2f7251e
util.xpcall, util.compat: Add non-hacky multi-argument xpcall() for Lua 5.1
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
29 } |
