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)
MODULES = $(DESTDIR)$(LIBDIR)/prosody/modules
SOURCE = $(DESTDIR)$(LIBDIR)/prosody
DATA = $(DESTDIR)$(DATADIR)
MAN = $(DESTDIR)$(PREFIX)/share/man
INSTALLEDSOURCE = $(LIBDIR)/prosody
INSTALLEDCONFIG = $(SYSCONFDIR)
INSTALLEDMODULES = $(LIBDIR)/prosody/modules
INSTALLEDDATA = $(DATADIR)
INSTALL=install -p
INSTALL_DATA=$(INSTALL) -m644
INSTALL_EXEC=$(INSTALL) -m755
MKDIR=install -d
MKDIR_PRIVATE=$(MKDIR) -m750
.PHONY: all test clean install
all: prosody.install prosodyctl.install prosody.cfg.lua.install prosody.version
$(MAKE) -C util-src install
.if $(EXCERTS) == "yes"
$(MAKE) -C certs localhost.crt example.com.crt
.endif
install: prosody.install prosodyctl.install prosody.cfg.lua.install util/encodings.so util/encodings.so util/pposix.so util/signal.so
$(MKDIR) $(BIN) $(CONFIG) $(MODULES) $(SOURCE)
$(MKDIR_PRIVATE) $(DATA)
$(MKDIR) $(MAN)/man1
$(MKDIR) $(CONFIG)/certs
$(MKDIR) $(SOURCE)/core $(SOURCE)/net $(SOURCE)/util
$(INSTALL_EXEC) ./prosody.install $(BIN)/prosody
$(INSTALL_EXEC) ./prosodyctl.install $(BIN)/prosodyctl
$(INSTALL_DATA) core/*.lua $(SOURCE)/core
$(INSTALL_DATA) net/*.lua $(SOURCE)/net
$(MKDIR) $(SOURCE)/net/http $(SOURCE)/net/resolvers $(SOURCE)/net/websocket
$(INSTALL_DATA) net/http/*.lua $(SOURCE)/net/http
$(INSTALL_DATA) net/resolvers/*.lua $(SOURCE)/net/resolvers
$(INSTALL_DATA) net/websocket/*.lua $(SOURCE)/net/websocket
$(INSTALL_DATA) util/*.lua $(SOURCE)/util
$(INSTALL_DATA) util/*.so $(SOURCE)/util
$(MKDIR) $(SOURCE)/util/sasl
$(INSTALL_DATA) util/sasl/*.lua $(SOURCE)/util/sasl
$(MKDIR) $(MODULES)/mod_s2s $(MODULES)/mod_pubsub $(MODULES)/adhoc $(MODULES)/muc $(MODULES)/mod_mam
$(INSTALL_DATA) plugins/*.lua $(MODULES)
$(INSTALL_DATA) plugins/mod_s2s/*.lua $(MODULES)/mod_s2s
$(INSTALL_DATA) plugins/mod_pubsub/*.lua $(MODULES)/mod_pubsub
$(INSTALL_DATA) plugins/adhoc/*.lua $(MODULES)/adhoc
$(INSTALL_DATA) plugins/muc/*.lua $(MODULES)/muc
$(INSTALL_DATA) plugins/mod_mam/*.lua $(MODULES)/mod_mam
.if $(EXCERTS) == "yes"
$(INSTALL_DATA) certs/localhost.crt certs/localhost.key $(CONFIG)/certs
$(INSTALL_DATA) certs/example.com.crt certs/example.com.key $(CONFIG)/certs
.endif
$(INSTALL_DATA) man/prosodyctl.man $(MAN)/man1/prosodyctl.1
test -f $(CONFIG)/prosody.cfg.lua || $(INSTALL_DATA) prosody.cfg.lua.install $(CONFIG)/prosody.cfg.lua
-test -f prosody.version && $(INSTALL_DATA) prosody.version $(SOURCE)/prosody.version
$(MAKE) install -C util-src
clean:
rm -f prosody.install
rm -f prosodyctl.install
rm -f prosody.cfg.lua.install
rm -f prosody.version
$(MAKE) clean -C util-src
test:
busted --lua=$(RUNWITH)
prosody.install: prosody
sed "1s| lua$$| $(RUNWITH)|; \
s|^CFG_SOURCEDIR=.*;$$|CFG_SOURCEDIR='$(INSTALLEDSOURCE)';|; \
s|^CFG_CONFIGDIR=.*;$$|CFG_CONFIGDIR='$(INSTALLEDCONFIG)';|; \
s|^CFG_DATADIR=.*;$$|CFG_DATADIR='$(INSTALLEDDATA)';|; \
s|^CFG_PLUGINDIR=.*;$$|CFG_PLUGINDIR='$(INSTALLEDMODULES)/';|;" < prosody > $@
prosodyctl.install: prosodyctl
sed "1s| lua$$| $(RUNWITH)|; \
s|^CFG_SOURCEDIR=.*;$$|CFG_SOURCEDIR='$(INSTALLEDSOURCE)';|; \
s|^CFG_CONFIGDIR=.*;$$|CFG_CONFIGDIR='$(INSTALLEDCONFIG)';|; \
s|^CFG_DATADIR=.*;$$|CFG_DATADIR='$(INSTALLEDDATA)';|; \
s|^CFG_PLUGINDIR=.*;$$|CFG_PLUGINDIR='$(INSTALLEDMODULES)/';|;" < prosodyctl > $@
prosody.cfg.lua.install: prosody.cfg.lua.dist
sed 's|certs/|$(INSTALLEDCONFIG)/certs/|' prosody.cfg.lua.dist > $@
prosody.version:
if [ -f prosody.release ]; then \
cp prosody.release $@; \
elif [ -f .hg_archival.txt ]; then \
sed -n 's/^node: \(............\).*/\1/p' .hg_archival.txt > $@; \
elif [ -f .hg/dirstate ]; then \
hexdump -n6 -e'6/1 "%02x"' .hg/dirstate > $@; \
else \
echo unknown > $@; \
fi