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.
include ../../config.unix
BIN = $(DESTDIR)$(PREFIX)/bin
CONFIG = $(DESTDIR)$(SYSCONFDIR)
SOURCE = $(DESTDIR)$(LIBDIR)/prosody
DATA = $(DESTDIR)$(DATADIR)
MAN = $(DESTDIR)$(PREFIX)/share/man
INSTALLEDSOURCE = $(LIBDIR)/prosody
INSTALLEDCONFIG = $(SYSCONFDIR)
INSTALLEDMODULES = $(LIBDIR)/prosody/modules
INSTALLEDDATA = $(DATADIR)
SOURCE_FILES = migrator/*.lua
all: prosody-migrator.install migrator.cfg.lua.install prosody-migrator.lua $(SOURCE_FILES)
install: prosody-migrator.install migrator.cfg.lua.install
install -d $(BIN) $(CONFIG) $(SOURCE) $(SOURCE)/migrator
install -d $(MAN)/man1
install -d $(SOURCE)/migrator
install -m755 ./prosody-migrator.install $(BIN)/prosody-migrator
install -m644 $(SOURCE_FILES) $(SOURCE)/migrator
test -e $(CONFIG)/migrator.cfg.lua || install -m644 migrator.cfg.lua.install $(CONFIG)/migrator.cfg.lua
clean:
rm -f prosody-migrator.install
rm -f migrator.cfg.lua.install
prosody-migrator.install: prosody-migrator.lua
sed "1s/\blua\b/$(RUNWITH)/; \
s|^CFG_SOURCEDIR=.*;$$|CFG_SOURCEDIR='$(INSTALLEDSOURCE)';|; \
s|^CFG_CONFIGDIR=.*;$$|CFG_CONFIGDIR='$(INSTALLEDCONFIG)';|;" \
< prosody-migrator.lua > prosody-migrator.install
migrator.cfg.lua.install: migrator.cfg.lua
sed "s|^local data_path = .*;$$|local data_path = '$(INSTALLEDDATA)';|;" \
< migrator.cfg.lua > migrator.cfg.lua.install