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33 Commits
v1.6 ... v1.8

Author SHA1 Message Date
Jan Engelhardt
85cab10371 Xtables-addons 1.8 2009-01-10 14:05:46 +01:00
Jan Engelhardt
61d8425cb6 Merge branch 'TEE6' 2009-01-10 14:03:04 +01:00
Jan Engelhardt
d49b6244c1 Merge branch 'TEE' 2009-01-10 14:03:03 +01:00
Jan Engelhardt
10c2b97786 Merge branch 'ipp2p' 2009-01-10 13:59:43 +01:00
Jan Engelhardt
9ed364ed36 TEE: collapse tee_tg_send{4,6} 2009-01-10 13:58:19 +01:00
Jan Engelhardt
b95e5f6417 TEE: IPv6 support for iptables module 2009-01-10 10:19:21 +01:00
Jan Engelhardt
4afebf88eb Merge branch 'TEE' into TEE6 2009-01-10 10:01:31 +01:00
Jan Engelhardt
d523158e92 TEE: iptables -nL and -L produced conversely output 2009-01-10 10:01:27 +01:00
Jan Engelhardt
1fd1787a1c TEE: limit iptables module to NFPROTO_IPV4
The code here is only usable with IPv4.
2009-01-10 09:57:44 +01:00
Jan Engelhardt
fbbca68790 ipp2p: partial revert of 3c8131b9
Revert part of 3c8131b976.

The transport header offset is not (yet) set by the time Netfilter
is invoked so using tcp_hdr/udp_hdr has undefined behavior.
2009-01-10 08:25:42 +01:00
Jan Engelhardt
4cdfd49637 ipp2p: add boundary check in search_all_kazaa
To avoid underflow on "end - 18", we must check for plen >= 18.
2009-01-10 06:11:13 +01:00
Jan Engelhardt
31c01cf107 portscan: update manpage about --grscan caveats 2009-01-10 05:23:43 +01:00
Jan Engelhardt
879e964f60 ipp2p: remove log flooding
Syslog was flooded by lots of messages due to if (plen >= 5) firing
on any packet, when it should have been plen < 5. Incidentally, this
turned up that plen also takes on huge nonsense values, assuming
underflow - yet to be investigated.
2009-01-10 04:47:14 +01:00
Jan Engelhardt
019c9de291 ipp2p: update help text
More suggestions from Stanley Pinchak.
2009-01-10 04:42:27 +01:00
Jan Engelhardt
af370f81f0 ipp2p: update manpage
(With suggestions from Stanley Pinchak.)
2009-01-09 20:24:41 +01:00
Jan Engelhardt
598c7ede37 Xtables-addons 1.7 2008-12-25 20:10:38 +01:00
Jan Engelhardt
2f66755226 Merge branch 'ipp2p' 2008-12-10 16:51:34 +01:00
Jan Engelhardt
d01a5f3d17 ipp2p: ensure better array bounds checking 2008-12-10 16:50:45 +01:00
Jan Engelhardt
bbda3e53da Merge branch 'SYSRQ' 2008-12-10 16:03:13 +01:00
Jan Engelhardt
22e73ea31f xt_SYSRQ: src: prefix variables 2008-12-10 16:02:21 +01:00
Jan Engelhardt
6b37f201d7 xt_SYSRQ: make new code compile for kernel <= 2.6.23 2008-12-10 15:45:43 +01:00
John Haxby
94ecf3847b xt_SYSRQ: improve security
I want to be able to use SYSRQ to reboot, crash or partially diagnose
machines that become unresponsive for one reason or another. These
machines, typically, are blades or rack mounted machines that do not
have a PS/2 connection for a keyboard and the old method of wheeling
round a "crash trolley" that has a monitor and a keyboard on it no
longer works: USB keyboards rarely, if ever, work because by the time
the machine is responding only to a ping, udev is incapable of
setting up a new keyboard.

This patch extends the xt_SYSRQ module to avoid both disclosing the
sysrq password and preventing replay. This is done by changing the
request packet from the simple "<key><password>" to a slightly more
complex "<key>,<seqno>,<salt>,<hash>". The hash is the sha1 checksum
of "<key>,<seqno>,<salt>,<password>". A request can be constructed in
a small shell script (see manpage).

Verification of the hash in xt_SYSRQ follows much the same process.
The sequence number, seqno, is initialised to the current time (in
seconds) when the xt_SYSRQ module is loaded and is updated each time
a valid request is received. A request with a sequence number less
than the current sequence number or a wrong hash is silently ignored.
(Using the time for the sequence number assumes (requires) that time
doesn't go backwards on a reboot and that the requester and victim
have reasonably synchronized clocks.)

The random salt is there to prevent pre-computed dictionary attacks
difficult: dictionary attacks are still feasible if you capture a
packet because the hash is computed quickly -- taking perhaps several
milliseconds to compute a more complex hash in xt_SYSRQ when the
machine is unresponsive is probably not the best thing you could do.
However, cracking, say, a random 32 character password would take
some time and is probably beyond what the people in the target
untrustworthy environment are prepared to do or have the resources
for. It almost goes without saying that no two victim machines should
use the same password.

Finally, the module allocates all the resources it need at module
initialisation time on the assumption that if things are going badly
resource allocation is going to be troublesome.
2008-12-02 19:45:22 +01:00
Jan Engelhardt
ee968691d7 ipp2p: fix newline inspection in kazaa
LFCR looks suspect, it should most likely be CRLF.
2008-11-26 00:47:36 +01:00
Jan Engelhardt
22db3bcb9c ipp2p: kazaa code cleanup 2008-11-26 00:46:44 +01:00
Jan Engelhardt
7da803e908 doc: add manpages for xt_ECHO and xt_TEE 2008-11-24 17:42:32 +01:00
Jan Engelhardt
4aad07bdc4 TEE: IPv6 support 2008-11-21 01:15:21 +01:00
Jan Engelhardt
7a3f874753 TEE: various cleanups, add comments
Normalize function names in light of upcoming IPv6 support.
Reformat other lines.
Add comment note about tee_send4.
2008-11-21 01:15:03 +01:00
Jan Engelhardt
f77a8e2eda TEE: do not use TOS for routing
Otherwise the cloned packet may be subject to more policy routing
rules than expected.
2008-11-21 01:15:02 +01:00
Jan Engelhardt
bd99e950f5 ipset: enable building of new modules
Whoops, modules need to be listed in GNUmakefile.in!
(Needed for out-of-srcdir builds.)
2008-11-20 23:08:33 +01:00
Jan Engelhardt
fdb7f34bc8 build: use new vars from automake-tranquility-3 2008-11-20 21:17:42 +01:00
Jan Engelhardt
85e3c24167 build: do not unconditionally install ipset
build_ipset=n was not completely respected and the ipset userspace
parts were still installed. This is now fixed.
2008-11-20 20:19:55 +01:00
Jan Engelhardt
aab8dd360f src: avoid use of _init
Xtables-addons's extensions will always be built as modules, so it is
safe to use __attribute__((constructor)).
2008-11-20 20:00:26 +01:00
Jan Engelhardt
a8f60d0d4b xt_ECHO: compile fix 2008-11-19 17:38:45 +01:00
33 changed files with 588 additions and 165 deletions

13
INSTALL
View File

@@ -65,6 +65,19 @@ If you want to enable debugging, use
much easier.)
Build-time options
==================
V= controls the kernel's make verbosity.
V=0 "silent" (output filename)
V=1 "verbose" (entire gcc command line)
VU= controls the Xt-a make verbosity.
VU=0 output filename
VU=1 output filename and source file
VU=2 entire gcc command line
Note to distribution packagers
==============================

View File

@@ -1,12 +1,13 @@
# -*- Makefile -*-
ACLOCAL_AMFLAGS = -I m4
AUTOMAKE_OPTIONS = foreign subdir-objects
SUBDIRS = extensions extensions/ipset
SUBDIRS = extensions
man_MANS := xtables-addons.8
xtables-addons.8: ${srcdir}/xtables-addons.8.in extensions/matches.man extensions/targets.man
${AM_VERBOSE_GEN} sed -e '/@MATCHES@/ r extensions/matches.man' -e '/@TARGET@/ r extensions/targets.man' $< >$@;
${am__verbose_GEN}sed -e '/@MATCHES@/ r extensions/matches.man' -e '/@TARGET@/ r extensions/targets.man' $< >$@;
extensions/%:
${MAKE} ${AM_MAKEFLAGS} -C $(@D) $(@F)

View File

@@ -1,8 +1,9 @@
AC_INIT([xtables-addons], [1.6])
AC_INIT([xtables-addons], [1.8])
AC_CONFIG_HEADERS([config.h])
AC_CONFIG_MACRO_DIR([m4])
AC_PROG_INSTALL
AM_INIT_AUTOMAKE
AM_INIT_AUTOMAKE([-Wall])
AC_PROG_CC
AM_PROG_CC_C_O
AC_DISABLE_STATIC
@@ -63,4 +64,5 @@ AC_SUBST([kinclude_CFLAGS])
AC_SUBST([kbuilddir])
AC_SUBST([ksourcedir])
AC_SUBST([xtlibdir])
AC_OUTPUT([Makefile extensions/GNUmakefile extensions/ipset/GNUmakefile])
AC_CONFIG_FILES([Makefile extensions/GNUmakefile extensions/ipset/GNUmakefile])
AC_OUTPUT

View File

@@ -30,15 +30,17 @@ xtables_CFLAGS := @xtables_CFLAGS@
AM_CFLAGS := ${regular_CFLAGS} -I${top_srcdir}/include ${xtables_CFLAGS} ${kinclude_CFLAGS}
AM_DEPFLAGS = -Wp,-MMD,$(@D)/.$(@F).d,-MT,$@
ifeq (${V},)
AM_LIBTOOL_SILENT = --silent
AM_VERBOSE_CC = @echo " CC " $@;
AM_VERBOSE_CCLD = @echo " CCLD " $@;
AM_VERBOSE_CXX = @echo " CXX " $@;
AM_VERBOSE_CXXLD = @echo " CXXLD " $@;
AM_VERBOSE_AR = @echo " AR " $@;
AM_VERBOSE_GEN = @echo " GEN " $@;
endif
VU := 0
am__1verbose_CC_0 = @echo " CC " $@;
am__1verbose_CCLD_0 = @echo " CCLD " $@;
am__1verbose_GEN_0 = @echo " GEN " $@;
am__1verbose_CC_1 = @echo " CC " $@ "<-" $<;
am__1verbose_CCLD_1 = @echo " CCLD " $@ "<-" $^;
am__1verbose_GEN_1 = @echo " GEN " $@ "<-" $<;
am__verbose_CC = ${am__1verbose_CC_${VU}}
am__verbose_CCLD = ${am__1verbose_CCLD_${VU}}
am__verbose_GEN = ${am__1verbose_GEN_${VU}}
#
# Wildcard module list
@@ -53,22 +55,30 @@ include ${srcdir}/Mbuild
#
# Building blocks
#
targets := ${obj-m}
targets_install := ${obj-m}
targets := $(filter-out %/,${obj-m})
targets_install := ${targets}
subdirs_list := $(filter %/,${obj-m})
.SECONDARY:
.PHONY: all install clean distclean FORCE
all: modules user matches.man targets.man
all: subdirs modules user matches.man targets.man
subdirs:
@for i in ${subdirs_list}; do ${MAKE} -C $$i; done;
subdirs-install:
@for i in ${subdirs_list}; do ${MAKE} -C $$i install; done;
user: ${targets}
install: modules_install ${targets_install}
install: modules_install subdirs-install ${targets_install}
@mkdir -p "${DESTDIR}${xtlibdir}";
install -pm0755 ${targets_install} "${DESTDIR}${xtlibdir}/";
clean: clean_modules
@for i in ${subdirs_list}; do make -C $$i clean; done;
rm -f *.oo *.so;
distclean: clean
@@ -96,10 +106,10 @@ clean_modules:
# Shared libraries
#
lib%.so: lib%.oo
${AM_VERBOSE_CCLD} ${CCLD} ${AM_LDFLAGS} -shared ${LDFLAGS} -o $@ $<;
${am__verbose_CCLD}${CCLD} ${AM_LDFLAGS} -shared ${LDFLAGS} -o $@ $<;
lib%.oo: ${srcdir}/lib%.c
${AM_VERBOSE_CC} ${CC} ${AM_DEPFLAGS} ${AM_CFLAGS} -D_INIT=lib$*_init -DPIC -fPIC ${CFLAGS} -o $@ -c $<;
${am__verbose_CC}${CC} ${AM_DEPFLAGS} ${AM_CFLAGS} -D_INIT=lib$*_init -DPIC -fPIC ${CFLAGS} -o $@ -c $<;
#
@@ -116,8 +126,7 @@ wlist_targets := $(patsubst ${srcdir}/libxt_%.man,%,${wcman_targets})
rm -f $@.tmp;
man_run = \
${AM_VERBOSE_GEN} \
for ext in $(1); do \
${am__verbose_GEN}for ext in $(1); do \
f="${srcdir}/libxt_$$ext.man"; \
if [ -f "$$f" ]; then \
echo ".SS $$ext"; \

View File

@@ -11,5 +11,6 @@ obj-${build_condition} += libxt_condition.so
obj-${build_fuzzy} += libxt_fuzzy.so
obj-${build_geoip} += libxt_geoip.so
obj-${build_ipp2p} += libxt_ipp2p.so
obj-${build_ipset} += ipset/
obj-${build_portscan} += libxt_portscan.so
obj-${build_quota2} += libxt_quota2.so

View File

@@ -32,20 +32,20 @@ xtables_CFLAGS := @xtables_CFLAGS@
AM_CFLAGS := ${regular_CFLAGS} -I${top_srcdir}/include ${xtables_CFLAGS} ${kinclude_CFLAGS} -DIPSET_LIB_DIR=\"${xtlibdir}\"
AM_DEPFLAGS = -Wp,-MMD,$(@D)/.$(@F).d,-MT,$@
ifeq (${V},)
AM_LIBTOOL_SILENT = --silent
AM_VERBOSE_CC = @echo " CC " $@;
AM_VERBOSE_CCLD = @echo " CCLD " $@;
AM_VERBOSE_CXX = @echo " CXX " $@;
AM_VERBOSE_CXXLD = @echo " CXXLD " $@;
AM_VERBOSE_AR = @echo " AR " $@;
AM_VERBOSE_GEN = @echo " GEN " $@;
endif
VU := 0
am__1verbose_CC_0 = @echo " CC " $@;
am__1verbose_CCLD_0 = @echo " CCLD " $@;
am__1verbose_CC_1 = @echo " CC " $@ "<-" $<;
am__1verbose_CCLD_1 = @echo " CCLD " $@ "<-" $^;
am__verbose_CC = ${am__1verbose_CC_${VU}}
am__verbose_CCLD = ${am__1verbose_CCLD_${VU}}
#
# Building blocks
#
targets := $(addsuffix .so,$(addprefix libipset_,iphash ipmap ipporthash iptree iptreemap macipmap nethash portmap))
targets := $(addsuffix .so,$(addprefix libipset_, \
iphash ipmap ipporthash ipportiphash ipportnethash iptree \
iptreemap macipmap nethash portmap setlist))
.SECONDARY:
@@ -69,16 +69,16 @@ distclean: clean
ipset: ipset.o
${AM_VERBOSE_CCLD} ${CCLD} ${AM_LDFLAGS} ${LDFLAGS} -o $@ $< -ldl -rdynamic;
${am__verbose_CCLD}${CCLD} ${AM_LDFLAGS} ${LDFLAGS} -o $@ $< -ldl -rdynamic;
#
# Shared libraries
#
lib%.so: lib%.oo
${AM_VERBOSE_CCLD} ${CCLD} ${AM_LDFLAGS} -shared ${LDFLAGS} -o $@ $<;
${am__verbose_CCLD}${CCLD} ${AM_LDFLAGS} -shared ${LDFLAGS} -o $@ $<;
libipset_%.oo: ${srcdir}/ipset_%.c
${AM_VERBOSE_CC} ${CC} ${AM_DEPFLAGS} ${AM_CFLAGS} -DPIC -fPIC ${CFLAGS} -o $@ -c $<;
${am__verbose_CC}${CC} ${AM_DEPFLAGS} ${AM_CFLAGS} -DPIC -fPIC ${CFLAGS} -o $@ -c $<;
%.o: %.c
${AM_VERBOSE_CC} ${CC} ${AM_DEPFLAGS} ${AM_CFLAGS} ${CFLAGS} -o $@ -c $<;
${am__verbose_CC}${CC} ${AM_DEPFLAGS} ${AM_CFLAGS} ${CFLAGS} -o $@ -c $<;

View File

@@ -106,8 +106,7 @@ static struct xtables_target chaos_tg_reg = {
.extra_opts = chaos_tg_opts,
};
void _init(void);
void _init(void)
static __attribute__((constructor)) void chaos_tg_ldr(void)
{
xtables_register_target(&chaos_tg_reg);
}

View File

@@ -41,8 +41,7 @@ static struct xtables_target delude_tg_reg = {
.final_check = delude_tg_check,
};
void _init(void);
void _init(void)
static __attribute__((constructor)) void delude_tg_ldr(void)
{
xtables_register_target(&delude_tg_reg);
}

View File

@@ -95,7 +95,7 @@ static struct xtables_target dhcpaddr_tg_reg = {
.extra_opts = dhcpaddr_tg_opts,
};
static void _init(void)
static __attribute__((constructor)) void dhcpaddr_tg_ldr(void)
{
xtables_register_target(&dhcpaddr_tg_reg);
}

View File

@@ -37,7 +37,7 @@ static struct xtables_target echo_tg_reg = {
.final_check = echo_tg_check,
};
static void _init(void)
static __attribute__((constructor)) void echo_tg_ldr(void)
{
xtables_register_target(&echo_tg_reg);
}

View File

@@ -0,0 +1,4 @@
The \fBECHO\fP target will send back all packets it received. It serves as an
examples for an Xtables target.
.PP
ECHO takes no options.

View File

@@ -68,7 +68,7 @@ static int ipmark_tg_parse(int c, char **argv, int invert, unsigned int *flags,
exit_error(PARAMETER_PROBLEM, "Bad addr value `%s' - should be `src' or `dst'", optarg);
*flags |= FL_ADDR_USED;
return true;
case '2':
param_act(P_ONLY_ONCE, "IPMARK", "and-mask", *flags & FL_AND_MASK_USED);
param_act(P_NO_INVERT, "IPMARK", "and-mask", invert);
@@ -175,7 +175,7 @@ static struct xtables_target ipmark_tg6_reg = {
.extra_opts = ipmark_tg_opts,
};
static void _init(void)
static __attribute__((constructor)) void ipmark_tg_ldr(void)
{
xtables_register_target(&ipmark_tg4_reg);
xtables_register_target(&ipmark_tg6_reg);

View File

@@ -111,8 +111,7 @@ static struct xtables_target logmark_tg_reg = {
.extra_opts = logmark_tg_opts,
};
void _init(void);
void _init(void)
static __attribute__((constructor)) void logmark_tg_ldr(void)
{
xtables_register_target(&logmark_tg_reg);
}

View File

@@ -43,7 +43,7 @@ static struct xtables_target sysrq_tg6_reg = {
.final_check = sysrq_tg_check,
};
static void _init(void)
static __attribute__((constructor)) void sysrq_tg_ldr(void)
{
xtables_register_target(&sysrq_tg4_reg);
xtables_register_target(&sysrq_tg6_reg);

View File

@@ -1,17 +1,19 @@
The SYSRQ target allows to remotely trigger sysrq on the local machine over the
network. This can be useful when vital parts of the machine hang, for example
an oops in a filesystem causing locks to be not released and processes to get
stuck as a result -- if still possible, use /proc/sysrq-trigger. Even when
stuck as a result - if still possible, use /proc/sysrq-trigger. Even when
processes are stuck, interrupts are likely to be still processed, and as such,
sysrq can be triggered through incoming network packets.
.PP
This xt_SYSRQ implementation does not use any encryption, so you should change
the SYSRQ password after use unless you have made sure it was transmitted
securely and no one sniffed the network, e.g. by use of an IPsec tunnel whose
endpoint is at the machine where you want to trigger the sysrq. Also, you
should limit as to who can issue commands using \fB-s\fP and/or \fB-m mac\fP,
and also that the destination is correct using \fB-d\fP (to protect against
potential broadcast packets), noting that it is still short of MAC/IP spoofing:
The xt_SYSRQ implementation uses a salted hash and a sequence number to prevent
network sniffers from either guessing the password or replaying earlier
requests. The initial sequence number comes from the time of day so you will
have a small window of vulnerability should time go backwards at a reboot.
However, the file /sys/module/xt_SYSREQ/seqno can be used to both query and
update the current sequence number. Also, you should limit as to who can issue
commands using \fB-s\fP and/or \fB-m mac\fP, and also that the destination is
correct using \fB-d\fP (to protect against potential broadcast packets), noting
that it is still short of MAC/IP spoofing:
.IP
-A INPUT -s 10.10.25.1 -m mac --mac-source aa:bb:cc:dd:ee:ff -d 10.10.25.7
-p udp --dport 9 -j SYSRQ
@@ -20,28 +22,59 @@ potential broadcast packets), noting that it is still short of MAC/IP spoofing:
ipsec --proto esp --tunnel-src 10.10.25.1 --tunnel-dst 10.10.25.7
-p udp --dport 9 -j SYSRQ
.PP
You should also limit the rate at which connections can be received to limit
the CPU time taken by illegal requests, for example:
.IP
-A INPUT 0s 10.10.25.1 -m mac --mac-source aa:bb:cc:dd:ee:ff -d 10.10.25.7
-p udp --dport 9 -m limit --limit 5/minute -j SYSRQ
.PP
This extension does not take any options. The \fB-p udp\fP options are
required.
.PP
The SYSRQ password can be changed through
/sys/module/xt_SYSRQ/parameters/password; note you need to use `echo -n` to
not add a newline to the password, i.e.
/sys/module/xt_SYSRQ/parameters/password, for example:
.IP
echo -n "password" >/sys/.../password
echo -n "password" >/sys/module/xt_SYSRQ/parameters/password
.PP
Alternatively, the password may be specified at modprobe time, but this is
insecure as people can possible see it through ps(1). You can use an option
line in /etc/modprobe.d/sysrq if it is properly guarded, that is, only readable
by root.
line in e.g. /etc/modprobe.d/xt_sysrq if it is properly guarded, that is, only
readable by root.
.IP
options xt_SYSRQ password=cookies
.PP
To trigger SYSRQ from a remote host, just use netcat or socat, specifying the
action (only one) as first character, followed by the password:
The hash algorithm can also be specified as a module option, for example, to
use SHA-256 instead of the default SHA-1:
.IP
echo -n "scookies" | socat stdin udp-sendto:10.10.25.7:9
.IP
echo -n "scookies" | netcat -u 10.10.25.7 9
options xt_SYSRQ hash=sha256
.PP
See the Linux docs for possible sysrq keys. Important ones are:
re(b)oot, power(o)ff, (s)ync filesystems, (u)mount and remount readonly.
The xt_SYSRQ module is normally silent unless a successful request is received,
but the \fIdebug\fP module parameter can be used to find exactly why a
seemingly correct request is not being processed.
.PP
To trigger SYSRQ from a remote host, just use netcat or socat:
.PP
.nf
sysrq_key="s" # the SysRq key(s)
password="password"
seqno="$(date +%s)"
salt="$(dd bs=12 count=1 if=/dev/urandom 2>/dev/null |
openssl enc -base64)"
req="$sysrq_key,$seqno,$salt"
req="$req,$(echo -n "$req,$password" | sha1sum | cut -c1-40)"
echo "$req" | socat stdin udp-sendto:10.10.25.7:9
# or
echo "$req" | netcat -uw1 10.10.25.7 9
.fi
.PP
See the Linux docs for possible sysrq keys. Important ones are: re(b)oot,
power(o)ff, (s)ync filesystems, (u)mount and remount readonly. More than one
sysrq key can be used at once, but bear in mind that, for example, a sync may
not complete before a subsequent reboot or poweroff.
.PP
The hashing scheme should be enough to prevent mis-use of SYSRQ in many
environments, but it is not perfect: take reasonable precautions to
protect your machines. Most importantly ensure that each machine has a
different password; there is scant protection for a SYSRQ packet being
applied to a machine that happens to have the same password.

View File

@@ -32,7 +32,7 @@ static struct xtables_target tarpit_tg_reg = {
.final_check = tarpit_tg_check,
};
static void _init(void)
static __attribute__((constructor)) void tarpit_tg_ldr(void)
{
xtables_register_target(&tarpit_tg_reg);
}

View File

@@ -1,7 +1,7 @@
/*
* "TEE" target extension for iptables
* Copyright © Sebastian Claßen <sebastian.classen [at] freenet.ag>, 2007
* Jan Engelhardt <jengelh [at] medozas de>, 2007 - 2008
* Jan Engelhardt <jengelh [at] medozas de>, 2007 - 2009
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License; either
@@ -70,6 +70,35 @@ static int tee_tg_parse(int c, char **argv, int invert, unsigned int *flags,
return false;
}
static int tee_tg6_parse(int c, char **argv, int invert, unsigned int *flags,
const void *entry, struct xt_entry_target **target)
{
struct xt_tee_tginfo *info = (void *)(*target)->data;
const struct in6_addr *ia;
switch (c) {
case 'g':
if (*flags & FLAG_GATEWAY)
exit_error(PARAMETER_PROBLEM,
"Cannot specify --gw more than once");
if (check_inverse(optarg, &invert, NULL, 0))
exit_error(PARAMETER_PROBLEM,
"Unexpected \"!\" after --gateway");
ia = numeric_to_ip6addr(optarg);
if (ia == NULL)
exit_error(PARAMETER_PROBLEM,
"Invalid IP address %s", optarg);
memcpy(&info->gw, ia, sizeof(*ia));
*flags |= FLAG_GATEWAY;
return true;
}
return false;
}
static void tee_tg_check(unsigned int flags)
{
if (flags == 0)
@@ -83,9 +112,20 @@ static void tee_tg_print(const void *ip, const struct xt_entry_target *target,
const struct xt_tee_tginfo *info = (const void *)target->data;
if (numeric)
printf("TEE gw:%s ", ipaddr_to_anyname(&info->gw.in));
else
printf("TEE gw:%s ", ipaddr_to_numeric(&info->gw.in));
else
printf("TEE gw:%s ", ipaddr_to_anyname(&info->gw.in));
}
static void tee_tg6_print(const void *ip, const struct xt_entry_target *target,
int numeric)
{
const struct xt_tee_tginfo *info = (const void *)target->data;
if (numeric)
printf("TEE gw:%s ", ip6addr_to_numeric(&info->gw.in6));
else
printf("TEE gw:%s ", ip6addr_to_anyname(&info->gw.in6));
}
static void tee_tg_save(const void *ip, const struct xt_entry_target *target)
@@ -95,9 +135,18 @@ static void tee_tg_save(const void *ip, const struct xt_entry_target *target)
printf("--gateway %s ", ipaddr_to_numeric(&info->gw.in));
}
static void tee_tg6_save(const void *ip, const struct xt_entry_target *target)
{
const struct xt_tee_tginfo *info = (const void *)target->data;
printf("--gateway %s ", ip6addr_to_numeric(&info->gw.in6));
}
static struct xtables_target tee_tg_reg = {
.name = "TEE",
.version = XTABLES_VERSION,
.revision = 0,
.family = PF_INET,
.size = XT_ALIGN(sizeof(struct xt_tee_tginfo)),
.userspacesize = XT_ALIGN(sizeof(struct xt_tee_tginfo)),
.help = tee_tg_help,
@@ -108,7 +157,23 @@ static struct xtables_target tee_tg_reg = {
.extra_opts = tee_tg_opts,
};
static void _init(void)
static struct xtables_target tee_tg6_reg = {
.name = "TEE",
.version = XTABLES_VERSION,
.revision = 0,
.family = PF_INET6,
.size = XT_ALIGN(sizeof(struct xt_tee_tginfo)),
.userspacesize = XT_ALIGN(sizeof(struct xt_tee_tginfo)),
.help = tee_tg_help,
.parse = tee_tg6_parse,
.final_check = tee_tg_check,
.print = tee_tg6_print,
.save = tee_tg6_save,
.extra_opts = tee_tg_opts,
};
static __attribute__((constructor)) void tee_tg_ldr(void)
{
xtables_register_target(&tee_tg_reg);
xtables_register_target(&tee_tg6_reg);
}

8
extensions/libxt_TEE.man Normal file
View File

@@ -0,0 +1,8 @@
The \fBTEE\fP target will clone a packet and redirect this clone to another
machine on the \fBlocal\fP network segment. In other words, the nexthop
must be the target, or you will have to configure the nexthop to forward it
further if so desired.
.TP
\fB--gw\fP \fIipaddr\fP
Send the cloned packet to the host reachable at the given IP address.
Use of 0.0.0.0 (for IPv4 packets) or :: (IPv6) is invalid.

View File

@@ -92,7 +92,7 @@ static struct xtables_match condition_mt_reg = {
.extra_opts = condition_opts,
};
static void _init(void)
static __attribute__((constructor)) void condition_mt_ldr(void)
{
xtables_register_match(&condition_mt_reg);
}

View File

@@ -96,7 +96,7 @@ static struct xtables_match dhcpaddr_mt_reg = {
.extra_opts = dhcpaddr_mt_opts,
};
static void _init(void)
static __attribute__((constructor)) void dhcpaddr_mt_ldr(void)
{
xtables_register_match(&dhcpaddr_mt_reg);
}

View File

@@ -112,7 +112,7 @@ static struct xtables_match fuzzy_mt_reg = {
.extra_opts = fuzzy_mt_opts,
};
static void _init(void)
static __attribute__((constructor)) void fuzzy_mt_ldr(void)
{
xtables_register_match(&fuzzy_mt_reg);
}

View File

@@ -272,7 +272,7 @@ static struct xtables_match geoip_match = {
.extra_opts = geoip_opts,
};
static void _init(void)
static __attribute__((constructor)) void geoip_mt_ldr(void)
{
xtables_register_match(&geoip_match);
}

View File

@@ -22,7 +22,7 @@
static void ipp2p_mt_help(void)
{
printf(
"IPP2P v%s options:\n"
"ipp2p v%s match options:\n"
" --edk [tcp,udp] All known eDonkey/eMule/Overnet packets\n"
" --dc [tcp] All known Direct Connect packets\n"
" --kazaa [tcp,udp] All known KaZaA packets\n"
@@ -32,19 +32,10 @@ static void ipp2p_mt_help(void)
" --winmx [tcp] All known WinMX\n"
" --soul [tcp] All known SoulSeek\n"
" --ares [tcp] All known Ares\n\n"
"EXPERIMENTAL protocols (please send feedback to: ipp2p@ipp2p.org) :\n"
"EXPERIMENTAL protocols:\n"
" --mute [tcp] All known Mute packets\n"
" --waste [tcp] All known Waste packets\n"
" --xdcc [tcp] All known XDCC packets (only xdcc login)\n\n"
"DEBUG SUPPPORT, use only if you know why\n"
" --debug Generate kernel debug output, THIS WILL SLOW DOWN THE FILTER\n"
"\nIPP2P was intended for TCP only. Due to increasing usage of UDP we needed to change this.\n"
"You can now use -p udp to search UDP packets only or without -p switch to search UDP and TCP packets.\n"
"\nSee README included with this package for more details or visit http://www.ipp2p.org\n"
"\nExamples:\n"
" iptables -A FORWARD -m ipp2p --ipp2p -j MARK --set-mark 0x01\n"
" iptables -A FORWARD -p udp -m ipp2p --kazaa --bit -j DROP\n"
" iptables -A FORWARD -p tcp -m ipp2p --edk --soul -j DROP\n\n"
, IPP2P_VERSION);
}
@@ -242,7 +233,7 @@ static struct xtables_match ipp2p_mt_reg = {
.extra_opts = ipp2p_mt_opts,
};
static void _init(void)
static __attribute__((constructor)) void ipp2p_mt_ldr(void)
{
xtables_register_match(&ipp2p_mt_reg);
}

View File

@@ -1,12 +1,12 @@
This module matches certain packets in P2P flows. It is not
designed to match all packets belonging to a P2P connection -
use IPP2P together with CONNMARK for this purpose. Also visit
http://www.ipp2p.org for detailed information.
use IPP2P together with CONNMARK for this purpose.
.PP
Use it together with -p tcp or -p udp to search these protocols
only or without -p switch to search packets of both protocols.
IPP2P provides the following options:
.PP
IPP2P provides the following options, of which one or more may be specified
on the command line:
.TP
.B "--edk "
Matches as many eDonkey/eMule packets as possible.
@@ -38,3 +38,11 @@ Matches Ares and AresLite packets. Use together with -j DROP only.
.B "--debug "
Prints some information about each hit into kernel logfile. May
produce huge logfiles so beware!
.PP
Note that ipp2p may not (and often, does not) identify all packets that are
exchanged as a result of running filesharing programs.
.PP
There is more information on http://ipp2p.org/ , but it has not been updated
since September 2006, and the syntax there is different from the ipp2p.c
provided in Xtables-addons; most importantly, the --ipp2p flag was removed due
to its ambiguity to match "all known" protocols.

View File

@@ -116,8 +116,7 @@ static struct xtables_match portscan_mt_reg = {
.extra_opts = portscan_mt_opts,
};
void _init(void);
void _init(void)
static __attribute__((constructor)) void portscan_mt_ldr(void)
{
xtables_register_match(&portscan_mt_reg);
}

View File

@@ -20,7 +20,11 @@ connection was torn down after completion of the 3-way handshake.
\fB--grscan\fR
Match if data in the connection only flew in the direction of the remote side,
e.g. if the connection was terminated after a locally running daemon sent its
identification. (e.g. openssh)
identification. (E.g. openssh, smtp, ftpd.) This may falsely trigger on
warranted single-direction data flows, usually bulk data transfers such as
FTP DATA connections or IRC DCC. Grab Scan Detection should only be used on
ports where a protocol runs that is guaranteed to do a bidirectional exchange
of bytes.
.PP
NOTE: Some clients (Windows XP for example) may do what looks like a SYN scan,
so be advised to carefully use xt_portscan in conjunction with blocking rules,

View File

@@ -133,7 +133,7 @@ static struct xtables_match quota_mt2_reg = {
.extra_opts = quota_mt2_opts,
};
static void _init(void)
static __attribute__((constructor)) void quota2_mt_ldr(void)
{
xtables_register_match(&quota_mt2_reg);
}

View File

@@ -32,6 +32,8 @@ echo_tg4(struct sk_buff **poldskb, const struct xt_target_param *par)
unsigned int addr_type, data_len;
void *payload;
printk(KERN_INFO "dst_out=%p\n", (*poldskb)->dst->output);
/* This allows us to do the copy operation in fewer lines of code. */
if (skb_linearize(*poldskb) < 0)
return NF_DROP;
@@ -75,10 +77,10 @@ echo_tg4(struct sk_buff **poldskb, const struct xt_target_param *par)
addr_type = RTN_UNSPEC;
#ifdef CONFIG_BRIDGE_NETFILTER
if (hooknum != NF_INET_FORWARD || (newskb->nf_bridge != NULL &&
if (par->hooknum != NF_INET_FORWARD || (newskb->nf_bridge != NULL &&
newskb->nf_bridge->mask & BRNF_BRIDGED))
#else
if (hooknum != NF_INET_FORWARD)
if (par->hooknum != NF_INET_FORWARD)
#endif
addr_type = RTN_LOCAL;

View File

@@ -3,7 +3,6 @@
* Copyright © Jan Engelhardt <jengelh [at] medozas de>, 2008
*
* Based upon the ipt_SYSRQ idea by Marek Zalem <marek [at] terminus sk>
* xt_SYSRQ does not use hashing or timestamps.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
@@ -19,15 +18,145 @@
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
#include <linux/netfilter/x_tables.h>
#include <linux/crypto.h>
#include <linux/scatterlist.h>
#include <net/ip.h>
#include "compat_xtables.h"
static bool sysrq_once;
static char sysrq_password[64];
static char sysrq_hash[16] = "sha1";
static long sysrq_seqno;
static int sysrq_debug;
module_param_string(password, sysrq_password, sizeof(sysrq_password),
S_IRUSR | S_IWUSR);
module_param_string(hash, sysrq_hash, sizeof(sysrq_hash), S_IRUSR);
module_param_named(seqno, sysrq_seqno, long, S_IRUSR | S_IWUSR);
module_param_named(debug, sysrq_debug, int, S_IRUSR | S_IWUSR);
MODULE_PARM_DESC(password, "password for remote sysrq");
MODULE_PARM_DESC(hash, "hash algorithm, default sha1");
MODULE_PARM_DESC(seqno, "sequence number for remote sysrq");
MODULE_PARM_DESC(debug, "debugging: 0=off, 1=on");
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 19)
static struct crypto_hash *sysrq_tfm;
static int sysrq_digest_size;
static unsigned char *sysrq_digest_password;
static unsigned char *sysrq_digest;
static char *sysrq_hexdigest;
/*
* The data is of the form "<requests>,<seqno>,<salt>,<hash>" where <requests>
* is a series of sysrq requests; <seqno> is a sequence number that must be
* greater than the last sequence number; <salt> is some random bytes; and
* <hash> is the hash of everything up to and including the preceding ","
* together with the password.
*
* For example
*
* salt=$RANDOM
* req="s,$(date +%s),$salt"
* echo "$req,$(echo -n $req,secret | sha1sum | cut -c1-40)"
*
* You will want a better salt and password than that though :-)
*/
static unsigned int sysrq_tg(const void *pdata, uint16_t len)
{
const char *data = pdata;
int i, n;
struct scatterlist sg[2];
struct hash_desc desc;
int ret;
long new_seqno = 0;
if (*sysrq_password == '\0') {
if (!sysrq_once)
printk(KERN_INFO KBUILD_MODNAME ": No password set\n");
sysrq_once = true;
return NF_DROP;
}
if (len == 0)
return NF_DROP;
for (i = 0; sysrq_password[i] != '\0' &&
sysrq_password[i] != '\n'; ++i)
/* loop */;
sysrq_password[i] = '\0';
i = 0;
for (n = 0; n < len - 1; ++n) {
if (i == 1 && '0' <= data[n] && data[n] <= '9')
new_seqno = 10L * new_seqno + data[n] - '0';
if (data[n] == ',' && ++i == 3)
break;
}
++n;
if (i != 3) {
if (sysrq_debug)
printk(KERN_WARNING KBUILD_MODNAME
": badly formatted request\n");
return NF_DROP;
}
if (sysrq_seqno >= new_seqno) {
if (sysrq_debug)
printk(KERN_WARNING KBUILD_MODNAME
": old sequence number ignored\n");
return NF_DROP;
}
desc.tfm = sysrq_tfm;
desc.flags = 0;
ret = crypto_hash_init(&desc);
if (ret != 0)
goto hash_fail;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 24)
sg_init_table(sg, 2);
#endif
sg_set_buf(&sg[0], data, n);
strcpy(sysrq_digest_password, sysrq_password);
i = strlen(sysrq_digest_password);
sg_set_buf(&sg[1], sysrq_digest_password, i);
ret = crypto_hash_digest(&desc, sg, n + i, sysrq_digest);
if (ret != 0)
goto hash_fail;
for (i = 0; i < sysrq_digest_size; ++i) {
sysrq_hexdigest[2*i] =
"0123456789abcdef"[(sysrq_digest[i] >> 4) & 0xf];
sysrq_hexdigest[2*i+1] =
"0123456789abcdef"[sysrq_digest[i] & 0xf];
}
sysrq_hexdigest[2*sysrq_digest_size] = '\0';
if (len - n < sysrq_digest_size) {
if (sysrq_debug)
printk(KERN_INFO KBUILD_MODNAME ": Short digest,"
" expected %s\n", sysrq_hexdigest);
return NF_DROP;
}
if (strncmp(data + n, sysrq_hexdigest, sysrq_digest_size) != 0) {
if (sysrq_debug)
printk(KERN_INFO KBUILD_MODNAME ": Bad digest,"
" expected %s\n", sysrq_hexdigest);
return NF_DROP;
}
/* Now we trust the requester */
sysrq_seqno = new_seqno;
for (i = 0; i < len && data[i] != ','; ++i) {
printk(KERN_INFO KBUILD_MODNAME ": SysRq %c\n", data[i]);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 19)
handle_sysrq(data[i], NULL);
#else
handle_sysrq(data[i], NULL, NULL);
#endif
}
return NF_ACCEPT;
hash_fail:
printk(KERN_WARNING KBUILD_MODNAME ": digest failure\n");
return NF_DROP;
}
#else
static unsigned int sysrq_tg(const void *pdata, uint16_t len)
{
const char *data = pdata;
@@ -57,6 +186,7 @@ static unsigned int sysrq_tg(const void *pdata, uint16_t len)
#endif
return NF_ACCEPT;
}
#endif
static unsigned int
sysrq_tg4(struct sk_buff **pskb, const struct xt_target_param *par)
@@ -73,9 +203,11 @@ sysrq_tg4(struct sk_buff **pskb, const struct xt_target_param *par)
udph = (void *)iph + ip_hdrlen(skb);
len = ntohs(udph->len) - sizeof(struct udphdr);
printk(KERN_INFO KBUILD_MODNAME ": " NIPQUAD_FMT ":%u -> :%u len=%u\n",
NIPQUAD(iph->saddr), htons(udph->source), htons(udph->dest),
len);
if (sysrq_debug)
printk(KERN_INFO KBUILD_MODNAME
": " NIPQUAD_FMT ":%u -> :%u len=%u\n",
NIPQUAD(iph->saddr), htons(udph->source),
htons(udph->dest), len);
return sysrq_tg((void *)udph + sizeof(struct udphdr), len);
}
@@ -94,14 +226,17 @@ sysrq_tg6(struct sk_buff **pskb, const struct xt_target_param *par)
udph = udp_hdr(skb);
len = ntohs(udph->len) - sizeof(struct udphdr);
printk(KERN_INFO KBUILD_MODNAME ": " NIP6_FMT ":%hu -> :%hu len=%u\n",
NIP6(iph->saddr), ntohs(udph->source),
ntohs(udph->dest), len);
if (sysrq_debug)
printk(KERN_INFO KBUILD_MODNAME
": " NIP6_FMT ":%hu -> :%hu len=%u\n",
NIP6(iph->saddr), ntohs(udph->source),
ntohs(udph->dest), len);
return sysrq_tg(udph + sizeof(struct udphdr), len);
}
static bool sysrq_tg_check(const struct xt_tgchk_param *par)
{
if (par->target->family == NFPROTO_IPV4) {
const struct ipt_entry *entry = par->entryinfo;
@@ -146,11 +281,64 @@ static struct xt_target sysrq_tg_reg[] __read_mostly = {
static int __init sysrq_tg_init(void)
{
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 19)
struct timeval now;
sysrq_tfm = crypto_alloc_hash(sysrq_hash, 0, CRYPTO_ALG_ASYNC);
if (IS_ERR(sysrq_tfm)) {
printk(KERN_WARNING KBUILD_MODNAME
": Error: Could not find or load %s hash\n",
sysrq_hash);
sysrq_tfm = NULL;
goto fail;
}
sysrq_digest_size = crypto_hash_digestsize(sysrq_tfm);
sysrq_digest = kmalloc(sysrq_digest_size, GFP_KERNEL);
if (sysrq_digest == NULL) {
printk(KERN_WARNING KBUILD_MODNAME
": Cannot allocate digest\n");
goto fail;
}
sysrq_hexdigest = kmalloc(2 * sysrq_digest_size + 1, GFP_KERNEL);
if (sysrq_hexdigest == NULL) {
printk(KERN_WARNING KBUILD_MODNAME
": Cannot allocate hexdigest\n");
goto fail;
}
sysrq_digest_password = kmalloc(sizeof(sysrq_password), GFP_KERNEL);
if (sysrq_digest_password == NULL) {
printk(KERN_WARNING KBUILD_MODNAME
": Cannot allocate password digest space\n");
goto fail;
}
do_gettimeofday(&now);
sysrq_seqno = now.tv_sec;
return xt_register_targets(sysrq_tg_reg, ARRAY_SIZE(sysrq_tg_reg));
fail:
if (sysrq_tfm)
crypto_free_hash(sysrq_tfm);
if (sysrq_digest)
kfree(sysrq_digest);
if (sysrq_hexdigest)
kfree(sysrq_hexdigest);
if (sysrq_digest_password)
kfree(sysrq_digest_password);
return -EINVAL;
#else
printk(KERN_WARNING "xt_SYSRQ does not provide crypto for <= 2.6.18\n");
return xt_register_targets(sysrq_tg_reg, ARRAY_SIZE(sysrq_tg_reg));
#endif
}
static void __exit sysrq_tg_exit(void)
{
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 19)
crypto_free_hash(sysrq_tfm);
kfree(sysrq_digest);
kfree(sysrq_hexdigest);
kfree(sysrq_digest_password);
#endif
return xt_unregister_targets(sysrq_tg_reg, ARRAY_SIZE(sysrq_tg_reg));
}

View File

@@ -1,7 +1,7 @@
/*
* "TEE" target extension for Xtables
* Copyright © Sebastian Claßen <sebastian.classen [at] freenet de>, 2007
* Jan Engelhardt <jengelh [at] medozas de>, 2007
* Jan Engelhardt <jengelh [at] medozas de>, 2007 - 2008
*
* based on ipt_ROUTE.c from Cédric de Launois
* <delaunois [at] info ucl ac be>
@@ -17,6 +17,7 @@
#include <net/checksum.h>
#include <net/icmp.h>
#include <net/ip.h>
#include <net/ip6_route.h>
#include <net/route.h>
#include <linux/netfilter/x_tables.h>
@@ -29,7 +30,7 @@ static struct nf_conn tee_track;
#include "compat_xtables.h"
#include "xt_TEE.h"
static const union nf_inet_addr zero_address;
static const union nf_inet_addr tee_zero_address;
/*
* Try to route the packet according to the routing keys specified in
@@ -47,21 +48,16 @@ static const union nf_inet_addr zero_address;
* true - if the packet was succesfully routed to the
* destination desired
*/
static bool tee_routing(struct sk_buff *skb,
const struct xt_tee_tginfo *info)
static bool
tee_tg_route4(struct sk_buff *skb, const struct xt_tee_tginfo *info)
{
int err;
struct rtable *rt;
struct iphdr *iph = ip_hdr(skb);
struct flowi fl = {
.nl_u = {
.ip4_u = {
.daddr = info->gw.ip,
.tos = RT_TOS(iph->tos),
.scope = RT_SCOPE_UNIVERSE,
}
}
};
struct flowi fl;
memset(&fl, 0, sizeof(fl));
fl.nl_u.ip4_u.daddr = info->gw.ip;
fl.nl_u.ip4_u.scope = RT_SCOPE_UNIVERSE;
/* Trying to route the packet using the standard routing table. */
err = ip_route_output_key(&init_net, &rt, &fl);
@@ -72,22 +68,14 @@ static bool tee_routing(struct sk_buff *skb,
return false;
}
/* Drop old route. */
dst_release(skb->dst);
skb->dst = NULL;
/*
* Success if no oif specified or if the oif correspond to the
* one desired.
* [SC]: always the case, because we have no oif.
*/
skb->dst = &rt->u.dst;
skb->dev = skb->dst->dev;
skb->protocol = htons(ETH_P_IP);
return true;
}
static bool dev_hh_avail(const struct net_device *dev)
static inline bool dev_hh_avail(const struct net_device *dev)
{
#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 23)
return dev->hard_header != NULL;
@@ -103,14 +91,14 @@ static bool dev_hh_avail(const struct net_device *dev)
* POST: the packet is sent with the link layer header pushed
* the packet is destroyed
*/
static void tee_ip_direct_send(struct sk_buff *skb)
static void tee_tg_send(struct sk_buff *skb)
{
const struct dst_entry *dst = skb->dst;
const struct net_device *dev = dst->dev;
unsigned int hh_len = LL_RESERVED_SPACE(dev);
/* Be paranoid, rather than too clever. */
if (unlikely(skb_headroom(skb) < hh_len) && dev_hh_avail(dev)) {
if (unlikely(skb_headroom(skb) < hh_len && dev_hh_avail(dev))) {
struct sk_buff *skb2;
skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev));
@@ -142,7 +130,7 @@ static void tee_ip_direct_send(struct sk_buff *skb)
* packets when we see they already have that ->nfct.
*/
static unsigned int
tee_tg(struct sk_buff **pskb, const struct xt_target_param *par)
tee_tg4(struct sk_buff **pskb, const struct xt_target_param *par)
{
const struct xt_tee_tginfo *info = par->targinfo;
struct sk_buff *skb = *pskb;
@@ -200,8 +188,78 @@ tee_tg(struct sk_buff **pskb, const struct xt_target_param *par)
nf_conntrack_get(skb->nfct);
#endif
if (tee_routing(skb, info))
tee_ip_direct_send(skb);
/*
* Normally, we would just use ip_local_out. Because iph->check is
* already correct, we could take a shortcut and call dst_output
* [forwards to ip_output] directly. ip_output however will invoke
* Netfilter hooks and cause reentrancy. So we skip that too and go
* directly to ip_finish_output. Since we should not do XFRM, control
* passes to ip_finish_output2. That function is not exported, so it is
* copied here as tee_ip_direct_send.
*
* We do no XFRM on the cloned packet on purpose! The choice of
* iptables match options will control whether the raw packet or the
* transformed version is cloned.
*
* Also on purpose, no fragmentation is done, to preserve the
* packet as best as possible.
*/
if (tee_tg_route4(skb, info))
tee_tg_send(skb);
return XT_CONTINUE;
}
static bool
tee_tg_route6(struct sk_buff *skb, const struct xt_tee_tginfo *info)
{
struct dst_entry *dst;
struct flowi fl;
memset(&fl, 0, sizeof(fl));
fl.nl_u.ip6_u.daddr = info->gw.in6;
#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 25)
dst = ip6_route_output(NULL, &fl);
#else
dst = ip6_route_output(dev_net(skb->dev), NULL, &fl);
#endif
if (dst == NULL) {
if (net_ratelimit())
printk(KERN_ERR "ip6_route_output failed for tee\n");
return false;
}
dst_release(skb->dst);
skb->dst = dst;
skb->dev = skb->dst->dev;
skb->protocol = htons(ETH_P_IPV6);
return true;
}
static unsigned int
tee_tg6(struct sk_buff **pskb, const struct xt_target_param *par)
{
const struct xt_tee_tginfo *info = par->targinfo;
struct sk_buff *skb = *pskb;
/* Try silence. */
#ifdef WITH_CONNTRACK
if (skb->nfct == &tee_track.ct_general)
return NF_DROP;
#endif
if ((skb = skb_copy(skb, GFP_ATOMIC)) == NULL)
return XT_CONTINUE;
#ifdef WITH_CONNTRACK
nf_conntrack_put(skb->nfct);
skb->nfct = &tee_track.ct_general;
skb->nfctinfo = IP_CT_NEW;
nf_conntrack_get(skb->nfct);
#endif
if (tee_tg_route6(skb, info))
tee_tg_send(skb);
return XT_CONTINUE;
}
@@ -211,18 +269,31 @@ static bool tee_tg_check(const struct xt_tgchk_param *par)
const struct xt_tee_tginfo *info = par->targinfo;
/* 0.0.0.0 and :: not allowed */
return memcmp(&info->gw, &zero_address, sizeof(zero_address)) != 0;
return memcmp(&info->gw, &tee_zero_address,
sizeof(tee_zero_address)) != 0;
}
static struct xt_target tee_tg_reg __read_mostly = {
.name = "TEE",
.revision = 0,
.family = NFPROTO_IPV4,
.table = "mangle",
.target = tee_tg,
.targetsize = sizeof(struct xt_tee_tginfo),
.checkentry = tee_tg_check,
.me = THIS_MODULE,
static struct xt_target tee_tg_reg[] __read_mostly = {
{
.name = "TEE",
.revision = 0,
.family = NFPROTO_IPV4,
.table = "mangle",
.target = tee_tg4,
.targetsize = sizeof(struct xt_tee_tginfo),
.checkentry = tee_tg_check,
.me = THIS_MODULE,
},
{
.name = "TEE",
.revision = 0,
.family = NFPROTO_IPV6,
.table = "mangle",
.target = tee_tg6,
.targetsize = sizeof(struct xt_tee_tginfo),
.checkentry = tee_tg_check,
.me = THIS_MODULE,
},
};
static int __init tee_tg_init(void)
@@ -241,19 +312,20 @@ static int __init tee_tg_init(void)
tee_track.status |= IPS_NAT_DONE_MASK;
#endif
return xt_register_target(&tee_tg_reg);
return xt_register_targets(tee_tg_reg, ARRAY_SIZE(tee_tg_reg));
}
static void __exit tee_tg_exit(void)
{
xt_unregister_target(&tee_tg_reg);
xt_unregister_targets(tee_tg_reg, ARRAY_SIZE(tee_tg_reg));
/* [SC]: shoud not we cleanup tee_track here? */
}
module_init(tee_tg_init);
module_exit(tee_tg_exit);
MODULE_AUTHOR("Sebastian Claßen <sebastian.classen@freenet.ag>");
MODULE_AUTHOR("Jan Engelhardt <jengelh@computergmbh.de>");
MODULE_AUTHOR("Jan Engelhardt <jengelh@medozas.de>");
MODULE_DESCRIPTION("Xtables: Reroute packet copy");
MODULE_LICENSE("GPL");
MODULE_ALIAS("ipt_TEE");
MODULE_ALIAS("ip6t_TEE");

View File

@@ -597,27 +597,51 @@ search_all_gnu(const unsigned char *payload, const unsigned int plen)
}
/* check for KaZaA download commands and other typical data */
/* plen is guaranteed to be >= 5 (see @matchlist) */
static unsigned int
search_all_kazaa(const unsigned char *payload, const unsigned int plen)
{
if (payload[plen-2] == 0x0d && payload[plen-1] == 0x0a) {
if (memcmp(payload, "GIVE ", 5) == 0)
return IPP2P_KAZAA * 100 + 1;
uint16_t c, end, rem;
if (memcmp(payload, "GET /", 5) == 0) {
uint16_t c = 8;
const uint16_t end = plen - 22;
if (plen < 5)
/* too short for anything we test for - early bailout */
return 0;
while (c < end) {
if (payload[c] == 0x0a &&
payload[c+1] == 0x0d &&
(memcmp(&payload[c+2], "X-Kazaa-Username: ", 18) == 0 ||
memcmp(&payload[c+2], "User-Agent: PeerEnabler/", 24) == 0))
return IPP2P_KAZAA * 100 + 2;
c++;
}
}
if (plen >= 65535) {
/* Something seems _really_ fishy */
printk(KERN_WARNING KBUILD_MODNAME ": %s: plen (%u) >= 65535\n",
__func__, plen);
return 0;
}
if (payload[plen-2] != 0x0d || payload[plen-1] != 0x0a)
return 0;
if (memcmp(payload, "GIVE ", 5) == 0)
return IPP2P_KAZAA * 100 + 1;
if (memcmp(payload, "GET /", 5) != 0)
return 0;
if (plen < 18)
/* The next tests would not succeed anyhow. */
return 0;
end = plen - 18;
rem = plen - 5;
for (c = 5; c < end; ++c, --rem) {
if (payload[c] != 0x0d)
continue;
if (payload[c+1] != 0x0a)
continue;
if (rem >= 18 &&
memcmp(&payload[c+2], "X-Kazaa-Username: ", 18) == 0)
return IPP2P_KAZAA * 100 + 2;
if (rem >= 24 &&
memcmp(&payload[c+2], "User-Agent: PeerEnabler/", 24) == 0)
return IPP2P_KAZAA * 100 + 2;
}
return 0;
}
@@ -813,7 +837,7 @@ ipp2p_mt(const struct sk_buff *skb, const struct xt_match_param *par)
switch (ip->protocol) {
case IPPROTO_TCP: /* what to do with a TCP packet */
{
const struct tcphdr *tcph = tcp_hdr(skb);
const struct tcphdr *tcph = (const void *)ip + ip_hdrlen(skb);
if (tcph->fin) return 0; /* if FIN bit is set bail out */
if (tcph->syn) return 0; /* if SYN bit is set bail out */
@@ -840,7 +864,7 @@ ipp2p_mt(const struct sk_buff *skb, const struct xt_match_param *par)
case IPPROTO_UDP: /* what to do with an UDP packet */
{
const struct udphdr *udph = udp_hdr(skb);
const struct udphdr *udph = (const void *)ip + ip_hdrlen(skb);
while (udp_list[i].command) {
if ((info->cmd & udp_list[i].command) == udp_list[i].command &&

2
m4/.gitignore vendored Normal file
View File

@@ -0,0 +1,2 @@
/libtool.m4
/lt*.m4

View File

@@ -1,4 +1,4 @@
.TH xtables\-addons 8 2008\-11\-18
.TH xtables\-addons 8 "v1.8 (2009\-01\-10)" "" "v1.8 (2009\-01\-10)"
.SH NAME
Xtables\-addons - additional extensions for iptables, ip6tables, etc.
.SH TARGETS