zapret/blockcheck.sh
2022-02-01 20:35:52 +03:00

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22 KiB
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Executable File

#!/bin/sh
EXEDIR="$(dirname "$0")"
EXEDIR="$(cd "$EXEDIR"; pwd)"
ZAPRET_BASE="$EXEDIR"
[ -n "$QNUM" ] || QNUM=59780
[ -n "$TPPORT" ] || TPPORT=993
[ -n "$TPWS_UID" ] || TPWS_UID=1
[ -n "$NFQWS" ] || NFQWS="$ZAPRET_BASE/nfq/nfqws"
[ -n "$DVTWS" ] || DVTWS="$ZAPRET_BASE/nfq/dvtws"
[ -n "$TPWS" ] || TPWS="$ZAPRET_BASE/tpws/tpws"
[ -n "$MDIG" ] || MDIG="$ZAPRET_BASE/mdig/mdig"
[ -n "$DESYNC_MARK" ] || DESYNC_MARK=0x40000000
[ -n "$IPFW_RULE_NUM" ] || IPFW_RULE_NUM=1
[ -n "$IPFW_DIVERT_PORT" ] || IPFW_DIVERT_PORT=59780
[ -n "$DOMAINS" ] || DOMAINS=rutracker.org
[ -n "$CURL_MAX_TIME" ] || CURL_MAX_TIME=5
[ -n "$MIN_TTL" ] || MIN_TTL=1
[ -n "$MAX_TTL" ] || MAX_TTL=12
HDRTEMP=/tmp/zapret-hdr.txt
ECHON="echo -n"
[ -n "$DNSCHECK_DNS" ] || DNSCHECK_DNS="8.8.8.8 1.1.1.1 77.88.8.1"
[ -n "$DNSCHECK_DOM" ] || DNSCHECK_DOM="pornhub.com putinhuylo.com rutracker.org nnmclub.to startmail.com"
DNSCHECK_DIG1=/tmp/dig1.txt
DNSCHECK_DIG2=/tmp/dig2.txt
DNSCHECK_DIGS=/tmp/digs.txt
exists()
{
which $1 >/dev/null 2>/dev/null
}
killwait()
{
# $1 - signal (-9, -2, ...)
# $2 - pid
kill $1 $2
# suppress job kill message
wait $2 2>/dev/null
}
exitp()
{
local A
echo
echo press enter to continue
read A
exit $1
}
read_yes_no()
{
# $1 - default (Y/N)
local A
read A
[ -z "$A" ] || ([ "$A" != "Y" ] && [ "$A" != "y" ] && [ "$A" != "N" ] && [ "$A" != "n" ]) && A=$1
[ "$A" = "Y" ] || [ "$A" = "y" ] || [ "$A" = "1" ]
}
ask_yes_no()
{
# $1 - default (Y/N or 0/1)
# $2 - text
local DEFAULT=$1
[ "$1" = "1" ] && DEFAULT=Y
[ "$1" = "0" ] && DEFAULT=N
[ -z "$DEFAULT" ] && DEFAULT=N
$ECHON "$2 (default : $DEFAULT) (Y/N) ? "
read_yes_no $DEFAULT
}
ask_yes_no_var()
{
# $1 - variable name for answer : 0/1
# $2 - text
local DEFAULT
eval DEFAULT="\$$1"
if ask_yes_no "$DEFAULT" "$2"; then
eval $1=1
else
eval $1=0
fi
}
require_root()
{
local exe
echo \* checking privileges
[ $(id -u) -ne "0" ] && {
echo root is required
exe="$EXEDIR/$(basename "$0")"
exists sudo && exec sudo "$exe"
exists su && exec su root -c "$exe"
echo su or sudo not found
exitp 2
}
}
IPT()
{
$IPTABLES -C "$@" >/dev/null 2>/dev/null || $IPTABLES -I "$@"
}
IPT_DEL()
{
$IPTABLES -C "$@" >/dev/null 2>/dev/null && $IPTABLES -D "$@"
}
IPFW_ADD()
{
ipfw -qf add $IPFW_RULE_NUM "$@"
}
IPFW_DEL()
{
ipfw -qf delete $IPFW_RULE_NUM
}
ipt6_has_raw()
{
ip6tables -nL -t raw >/dev/null 2>/dev/null
}
ipt_has_nfq()
{
# cannot just check /proc/net/ip_tables_targets because of iptables-nft or modules not loaded yet
local ipt
for ipt in iptables ip6tables; do
$ipt -A OUTPUT -t mangle -p 255 -j NFQUEUE --queue-num $QNUM --queue-bypass 2>/dev/null || return 1
$ipt -D OUTPUT -t mangle -p 255 -j NFQUEUE --queue-num $QNUM --queue-bypass 2>/dev/null
done
return 0
}
check_system()
{
echo \* checking system
UNAME=$(uname)
SUBSYS=
case "$UNAME" in
Linux)
PKTWS="$NFQWS"
PKTWSD=nfqws
local INIT=$(sed 's/\x0/\n/g' /proc/1/cmdline | head -n 1)
[ -L "$INIT" ] && INIT=$(readlink "$INIT")
INIT=$(basename "$INIT")
[ -f "/etc/openwrt_release" ] && exists opkg && exists uci && [ "$INIT" = "procd" ] && SUBSYS=openwrt
;;
FreeBSD)
PKTWS="$DVTWS"
PKTWSD=dvtws
;;
*)
echo $UNAME not supported
exitp 5
esac
echo $UNAME${SUBSYS:+/$SUBSYS} detected
}
freebsd_module_loaded()
{
# $1 - module name
kldstat -qm "${1}"
}
freebsd_modules_loaded()
{
# $1,$2,$3, ... - module names
while [ -n "$1" ]; do
freebsd_module_loaded $1 || return 1
shift
done
return 0
}
check_prerequisites()
{
echo \* checking prerequisites
[ -x "$PKTWS" ] && [ -x "$TPWS" ] && [ -x "$MDIG" ] || {
echo $PKTWS or $TPWS or $MDIG is not available. run \"$ZAPRET_BASE/install_bin.sh\" or make -C \"$ZAPRET_BASE\"
exitp 6
}
local prog progs='curl'
case "$UNAME" in
Linux)
progs="$progs iptables ip6tables"
ipt_has_nfq || {
echo NFQUEUE iptables or ip6tables target is missing. pls install modules.
[ "$SUBSYS" = openwrt ] && echo 'OpenWRT : opkg update ; opkg install iptables-mod-nfqueue'
exitp 6
}
;;
FreeBSD)
progs="$progs ipfw"
freebsd_modules_loaded ipfw ipdivert || {
echo ipfw or ipdivert kernel module not loaded
exitp 6
}
[ "$(sysctl -qn net.inet.ip.fw.enable)" = 0 -o "$(sysctl -qn net.inet6.ip6.fw.enable)" = 0 ] && {
echo ipfw is disabled. use : ipfw enable firewall
exitp 6
}
;;
esac
for prog in $progs; do
exists $prog || {
echo $prog does not exist. please install
exitp 6
}
done
if exists nslookup; then
LOOKUP=nslookup
elif exists host; then
LOOKUP=host
else
echo nslookup or host does not exist. please install
exitp 6
fi
}
curl_translate_code()
{
# $1 - code
$ECHON $1
case $1 in
0) $ECHON ": ok"
;;
1) $ECHON ": unsupported protocol"
;;
2) $ECHON ": early initialization code failed"
;;
3) $ECHON ": the URL was not properly formatted"
;;
4) $ECHON ": feature not supported by libcurl"
;;
5) $ECHON ": could not resolve proxy"
;;
6) $ECHON ": could not resolve host"
;;
7) $ECHON ": could not connect"
;;
8) $ECHON ": invalid server reply"
;;
9) $ECHON ": remote access denied"
;;
27) $ECHON ": out of memory"
;;
28) $ECHON ": operation timed out"
;;
35) $ECHON ": SSL connect error"
;;
esac
}
curl_supports_tls13()
{
curl --tlsv1.3 -Is -o /dev/null http://$LOCALHOST_IPT:65535 2>/dev/null
# return code 2 = init failed. likely bad command line options
[ $? = 2 ] && return 1
# curl can have tlsv1.3 key present but ssl library without TLS 1.3 support
# this is online test because there's no other way to trigger library incompatibility case
curl --tlsv1.3 --max-time $CURL_MAX_TIME -Is -o /dev/null https://w3.org 2>/dev/null
[ $? != 4 ]
}
curl_supports_tlsmax()
{
# supported only in OpenSSL
curl --version | grep -Fq OpenSSL || return 1
# supported since curl 7.54
curl --tls-max 1.2 -Is -o /dev/null http://$LOCALHOST_IPT:65535 2>/dev/null
# return code 2 = init failed. likely bad command line options
[ $? != 2 ]
}
hdrfile_http_code()
{
# $1 - hdr file
sed -nre '1,1 s/^HTTP\/1\.[0,1] ([0-9]+) .*$/\1/p' "$1"
}
hdrfile_location()
{
# $1 - hdr file
# some DPIs return CRLF line ending
tr -d '\015' <"$1" | sed -nre 's/^[Ll][Oo][Cc][Aa][Tt][Ii][Oo][Nn]:[ ]*([^ ]*)[ ]*$/\1/p'
}
curl_test_http()
{
# $1 - ip version : 4/6
# $2 - domain name
local code loc
curl -${1}SsD "$HDRTEMP" --max-time $CURL_MAX_TIME $CURL_OPT "http://$2" -o /dev/null 2>&1 || {
code=$?
rm -f "$HDRTEMP"
return $code
}
code=$(hdrfile_http_code "$HDRTEMP")
[ "$code" = 301 -o "$code" = 302 -o "$code" = 307 -o "$code" = 308 ] && {
loc=$(hdrfile_location "$HDRTEMP")
echo "$loc" | grep -qE "^https?://.*$2(/|$)" ||
echo "$loc" | grep -vqE '^https?://' || {
echo suspicious redirection $code to : $loc
rm -f "$HDRTEMP"
return 254
}
}
rm -f "$HDRTEMP"
return 0
}
curl_test_https_tls12()
{
# $1 - ip version : 4/6
# $2 - domain name
# prevent using QUIC if available in curl
# do not use tls 1.3 to make sure server certificate is not encrypted
curl -${1}ISs --max-time $CURL_MAX_TIME $CURL_OPT --http1.1 --tlsv1.2 $TLSMAX12 "https://$2" -o /dev/null 2>&1
}
curl_test_https_tls13()
{
# $1 - ip version : 4/6
# $2 - domain name
# prevent using QUIC if available in curl
# force TLS1.3 mode
curl -${1}ISs --max-time $CURL_MAX_TIME $CURL_OPT --http1.1 --tlsv1.3 $TLSMAX13 "https://$2" -o /dev/null 2>&1
}
pktws_ipt_prepare()
{
# $1 - port
case "$UNAME" in
Linux)
# to avoid possible INVALID state drop
IPT INPUT -p tcp --sport $1 ! --syn -j ACCEPT
IPT OUTPUT -p tcp --dport $1 -m conntrack --ctstate INVALID -j ACCEPT
if [ "$IPV" = 6 -a -n "$IP6_DEFRAG_DISABLE" ]; then
# the only way to reliable disable ipv6 defrag. works only in 4.16+ kernels
IPT OUTPUT -t raw -p tcp --dport $1 -j CT --notrack
elif [ "$IPV" = 4 ]; then
# enable fragments
IPT OUTPUT -f -j ACCEPT
fi
IPT POSTROUTING -t mangle -p tcp --dport $1 -m mark ! --mark $DESYNC_MARK/$DESYNC_MARK -j NFQUEUE --queue-num $QNUM
;;
FreeBSD)
IPFW_ADD divert $IPFW_DIVERT_PORT tcp from me to any 80,443 proto ip${IPV} out not diverted not sockarg
;;
esac
}
pktws_ipt_unprepare()
{
# $1 - port
case "$UNAME" in
Linux)
IPT_DEL POSTROUTING -t mangle -p tcp --dport $1 -m mark ! --mark $DESYNC_MARK/$DESYNC_MARK -j NFQUEUE --queue-num $QNUM
IPT_DEL INPUT -p tcp --sport $1 ! --syn -j ACCEPT
IPT_DEL OUTPUT -p tcp --dport $1 -m conntrack --ctstate INVALID -j ACCEPT
if [ "$IPV" = 6 -a -n "$IP6_DEFRAG_DISABLE" ]; then
IPT_DEL OUTPUT -t raw -p tcp --dport $1 -j CT --notrack
elif [ "$IPV" = 4 ]; then
IPT_DEL OUTPUT -f -j ACCEPT
fi
;;
FreeBSD)
IPFW_DEL
;;
esac
}
tpws_ipt_prepare()
{
# $1 - port
case "$UNAME" in
Linux)
IPT OUTPUT -t nat -p tcp --dport $1 -m owner ! --uid-owner $TPWS_UID -j DNAT --to $LOCALHOST_IPT:$TPPORT
;;
FreeBSD)
IPFW_ADD fwd $LOCALHOST,$TPPORT tcp from me to any 80,443 proto ip${IPV} not uid $TPWS_UID
;;
esac
}
tpws_ipt_unprepare()
{
# $1 - port
case "$UNAME" in
Linux)
IPT_DEL OUTPUT -t nat -p tcp --dport $1 -m owner ! --uid-owner $TPWS_UID -j DNAT --to $LOCALHOST_IPT:$TPPORT
;;
FreeBSD)
IPFW_DEL
;;
esac
}
pktws_start()
{
case "$UNAME" in
Linux)
"$NFQWS" --dpi-desync-fwmark=$DESYNC_MARK --qnum=$QNUM "$@" >/dev/null &
;;
FreeBSD)
"$DVTWS" --port=$IPFW_DIVERT_PORT "$@" >/dev/null &
;;
esac
PID=$!
}
tpws_start()
{
"$TPWS" --uid $TPWS_UID:$TPWS_UID --bind-addr=$LOCALHOST --port=$TPPORT "$@" >/dev/null &
PID=$!
# give some time to initialize
sleep 1
}
ws_kill()
{
[ -z "$PID" ] || {
killwait -9 $PID 2>/dev/null
PID=
}
}
curl_test()
{
# $1 - test function
# $2 - domain
local code=0 n=0
while [ $n -lt $REPEATS ]; do
n=$(($n+1))
[ $REPEATS -gt 1 ] && $ECHON "[attempt $n] "
$1 "$IPV" $2 && {
[ $REPEATS -gt 1 ] && echo 'AVAILABLE'
continue
}
code=$?
done
if [ $code = 254 ]; then
echo "UNAVAILABLE"
elif [ $code = 0 ]; then
echo '!!!!! AVAILABLE !!!!!'
else
echo "UNAVAILABLE code=$code"
fi
return $code
}
ws_curl_test()
{
# $1 - ws start function
# $2 - test function
# $3 - domain
# $4,$5,$6, ... - ws params
local code ws_start=$1 testf=$2 dom=$3
shift
shift
shift
$ws_start "$@"
curl_test $testf $dom
code=$?
ws_kill
return $code
}
tpws_curl_test()
{
# $1 - test function
# $2 - domain
# $3,$4,$5, ... - tpws params
echo - checking tpws $3 $4 $5 $6 $7 $8 $9
ws_curl_test tpws_start "$@"
}
pktws_curl_test()
{
# $1 - test function
# $2 - domain
# $3,$4,$5, ... - nfqws/dvtws params
echo - checking $PKTWSD $3 $4 $5 $6 $7 $8 $9
ws_curl_test pktws_start "$@"
}
xxxws_curl_test_update()
{
# $1 - xxx_curl_test function
# $2 - test function
# $3 - domain
# $4,$5,$6, ... - nfqws/dvtws params
local code xxxf=$1 testf=$2 dom=$3
shift
shift
shift
$xxxf $testf $dom "$@"
code=$?
[ $code = 0 ] && strategy="${strategy:-$@}"
return $code
}
pktws_curl_test_update()
{
xxxws_curl_test_update pktws_curl_test "$@"
}
tpws_curl_test_update()
{
xxxws_curl_test_update tpws_curl_test "$@"
}
report_append()
{
NREPORT=${NREPORT:-0}
eval REPORT_${NREPORT}=\"$@\"
NREPORT=$(($NREPORT+1))
}
report_print()
{
local n=0 s
NREPORT=${NREPORT:-0}
while [ $n -lt $NREPORT ]; do
eval s=\"\${REPORT_$n}\"
echo $s
n=$(($n+1))
done
}
report_strategy()
{
# $1 - test function
# $2 - domain
# $3 - daemon
echo
if [ -n "$strategy" ]; then
echo "!!!!! $1: working strategy found for ipv${IPV} $2 : $3 $strategy !!!!!"
echo
report_append "ipv${IPV} $2 $1 : $3 $strategy"
return 0
else
echo "$1: $3 strategy for ipv${IPV} $2 not found"
echo
report_append "ipv${IPV} $2 $1 : $3 not working"
return 1
fi
}
pktws_check_domain_bypass()
{
# $1 - test function
# $2 - encrypted test : 1/0
# $3 - domain
local strategy tests='fake' ttls s f e desync pos fooling frag sec="$2"
[ "$sec" = 0 ] && {
for s in '--hostcase' '--hostspell=hoSt' '--hostnospace' '--domcase'; do
pktws_curl_test_update $1 $3 $s
done
}
s="--dpi-desync=split2"
pktws_curl_test_update $1 $3 $s || {
tests="$tests split fake,split2 fake,split"
[ "$sec" = 0 ] && pktws_curl_test_update $1 $3 $s --hostcase
for pos in 1 3 4 5 10 50 100; do
s="--dpi-desync=split2 --dpi-desync-split-pos=$pos"
if pktws_curl_test_update $1 $3 $s; then
break
elif [ "$sec" = 0 ]; then
pktws_curl_test_update $1 $3 $s --hostcase
fi
done
}
pktws_curl_test_update $1 $3 --dpi-desync=disorder2 || tests="$tests disorder fake,disorder2 fake,disorder"
ttls=$(seq -s ' ' $MIN_TTL $MAX_TTL)
for e in '' '--wssize 1:6'; do
[ -n "$e" ] && {
pktws_curl_test_update $1 $3 $e
for desync in split2 disorder2; do
pktws_curl_test_update $1 $3 --dpi-desync=$desync $e
done
}
[ "$IPV" = 6 ] && pktws_curl_test_update $1 $3 $e --dpi-desync=hopbyhop
for desync in $tests; do
s="--dpi-desync=$desync"
for ttl in $ttls; do
pktws_curl_test_update $1 $3 $s --dpi-desync-ttl=$ttl $e && break
done
f="badsum badseq md5sig"
[ "$IPV" = 6 ] && f="$f hopbyhop hopbyhop2"
for fooling in $f; do
pktws_curl_test_update $1 $3 $s --dpi-desync-fooling=$fooling $e && [ "$fooling" = "md5sig" ] &&
echo 'WARNING ! although md5sig fooling worked it will not work on all sites. it typically works only on linux servers.'
done
done
# do not do wssize test for http. it's useless
[ "$sec" = 1 ] || break
done
[ "$IPV" = 4 -o -n "$IP6_DEFRAG_DISABLE" ] && {
for frag in 24 32 40 64 80 104; do
pktws_curl_test_update $1 $3 --dpi-desync=ipfrag2 --dpi-desync-ipfrag-pos-tcp=$frag
done
}
report_strategy $1 $3 $PKTWSD
}
tpws_check_domain_bypass()
{
# $1 - test function
# $2 - encrypted test : 1/0
# $3 - domain
local s pos strategy sec="$2"
if [ "$sec" = 0 ]; then
for s in '--hostcase' '--hostspell=hoSt' '--split-http-req=method' '--split-http-req=method --hostcase' '--split-http-req=host' '--split-http-req=host --hostcase' \
'--hostdot' '--hosttab' '--hostnospace' '--methodspace' '--methodeol' '--unixeol' \
'--hostpad=1024' '--hostpad=2048' '--hostpad=4096' '--hostpad=8192' '--hostpad=16384'; do
tpws_curl_test_update $1 $3 $s
done
else
for pos in 1 2 3 4 5 10 50 100; do
s="--split-pos=$pos"
tpws_curl_test_update $1 $3 $s && break
done
fi
report_strategy $1 $3 tpws
}
check_domain()
{
# $1 - test function
# $2 - port
# $3 - encrypted test : 1/0
# $4 - domain
local code c
echo
echo \* $1 ipv$IPV $4
# in case was interrupted before
pktws_ipt_unprepare $2
tpws_ipt_unprepare $2
ws_kill
echo "- checking without DPI bypass"
curl_test $1 $4 && {
report_append "ipv${IPV} $4 $1 : working without bypass"
return
}
code=$?
for c in 1 2 3 4 6 27 ; do
[ $code = $c ] && {
report_append "ipv${IPV} $4 $1 : test aborted, no reason to continue. curl code $(curl_translate_code $code)"
return
}
done
echo
echo preparing tpws redirection
tpws_ipt_prepare $2
tpws_check_domain_bypass $1 $3 $4
echo clearing tpws redirection
tpws_ipt_unprepare $2
echo
echo preparing $PKTWSD redirection
pktws_ipt_prepare $2
pktws_check_domain_bypass $1 $3 $4
echo clearing $PKTWSD redirection
pktws_ipt_unprepare $2
}
check_domain_http()
{
# $1 - domain
check_domain curl_test_http 80 0 $1
}
check_domain_https_tls12()
{
# $1 - domain
check_domain curl_test_https_tls12 443 1 $1
}
check_domain_https_tls13()
{
# $1 - domain
check_domain curl_test_https_tls13 443 1 $1
}
configure_ip_version()
{
if [ "$IPV" = 6 ]; then
IPTABLES=ip6tables
LOCALHOST=::1
LOCALHOST_IPT=[::1]
else
IPTABLES=iptables
LOCALHOST=127.0.0.1
LOCALHOST_IPT=127.0.0.1
fi
}
configure_curl_opt()
{
TLSMAX12=
TLSMAX13=
curl_supports_tlsmax && {
TLSMAX12="--tls-max 1.2"
TLSMAX13="--tls-max 1.3"
}
TLS13=
curl_supports_tls13 && TLS13=1
}
ask_params()
{
echo
echo NOTE ! this test should be run with zapret or any other bypass software disabled, without VPN
echo
echo "specify domain(s) to test. multiple domains are space separated."
$ECHON "domain(s) (default: $DOMAINS) : "
local dom
read dom
[ -n "$dom" ] && DOMAINS="$dom"
$ECHON "ip protocol version(s) - 4, 6 or 46 for both (default: 4) : "
read IPVS
[ -n "$IPVS" ] || IPVS=4
[ "$IPVS" = 4 -o "$IPVS" = 6 -o "$IPVS" = 46 ] || {
echo 'invalid ip version(s). should be 4, 6 or 46.'
exitp 1
}
[ "$IPVS" = 46 ] && IPVS="4 6"
configure_curl_opt
ENABLE_HTTP=1
ask_yes_no_var ENABLE_HTTP "check http"
[ -n "$TLSMAX12" ] || echo "WARNING ! your curl version or TLS library does not support tls-max option. TLS 1.2 tests may use TLS 1.3+ protocols"
ENABLE_HTTPS_TLS12=1
ask_yes_no_var ENABLE_HTTPS_TLS12 "check https tls 1.2"
ENABLE_HTTPS_TLS13=0
echo
if [ -n "$TLS13" ]; then
echo "TLS 1.3 is the new standard for encrypted communications over TCP"
echo "its the most important feature for DPI bypass is encrypted TLS ServerHello"
echo "more and more sites enable TLS 1.3 but still there're many sites with only TLS 1.2 support"
echo "with TLS 1.3 more DPI bypass strategies can work but they may not apply to all sites"
echo "if a strategy works with TLS 1.2 it will also work with TLS 1.3"
echo "if nothing works with TLS 1.2 this test may find TLS1.3 only strategies"
echo "make sure that $DOMAINS support TLS 1.3 otherwise all test will return an error"
ask_yes_no_var ENABLE_HTTPS_TLS13 "check https tls 1.3"
else
echo "installed curl version does not support TLS 1.3 . tests disabled."
fi
IGNORE_CA=0
CURL_OPT=
[ $ENABLE_HTTPS_TLS13 = 1 -o $ENABLE_HTTPS_TLS12 = 1 ] && {
echo
echo "on limited systems like openwrt CA certificates might not be installed to preserve space"
echo "in such a case curl cannot verify server certificate and you should either install ca-bundle or disable verification"
echo "however disabling verification will break https check if ISP does MitM attack and substitutes server certificate"
ask_yes_no_var IGNORE_CA "do not verify server certificate"
[ "$IGNORE_CA" = 1 ] && CURL_OPT=-k
}
echo
echo "sometimes ISPs use multiple DPIs or load balancing. bypass strategies may work unstable."
$ECHON "how many times to repeat each test (default: 1) : "
read REPEATS
REPEATS=$((0+${REPEATS:-1}))
[ "$REPEATS" = 0 ] && {
echo invalid repeat count
exitp 1
}
echo
case "$UNAME" in
Linux)
IP6_DEFRAG_DISABLE=
[ "$IPVS" = 6 -o "$IPVS" = "4 6" ] && {
local V1=$(sed -nre 's/^Linux version ([0-9]+)\.[0-9]+.*$/\1/p' /proc/version)
local V2=$(sed -nre 's/^Linux version [0-9]+\.([0-9]+).*$/\1/p' /proc/version)
if [ "$V1" -gt 4 -o "$V1" = 4 -a "$V2" -ge 16 ]; then
ipt6_has_raw && IP6_DEFRAG_DISABLE=1
[ -n "$IP6_DEFRAG_DISABLE" ] || {
echo "WARNING ! ip6tables raw table is not available, ipv6 ipfrag tests are disabled"
echo
}
else
echo "WARNING ! ipv6 defrag can only be effectively disabled in linux kernel 4.16+"
echo "WARNING ! ipv6 ipfrag tests are disabled"
echo
fi
}
;;
*)
IP6_DEFRAG_DISABLE=1
;;
esac
}
pingtest()
{
ping -c 1 -W 1 $1 >/dev/null
}
dnstest()
{
# $1 - dns server. empty for system resolver
"$LOOKUP" w3.org $1 >/dev/null 2>/dev/null
}
find_working_public_dns()
{
local dns
for dns in $DNSCHECK_DNS; do
pingtest $dns && dnstest $dns && {
PUBDNS=$dns
return 0
}
done
return 1
}
lookup4()
{
# $1 - domain
# $2 - DNS
case "$LOOKUP" in
nslookup)
nslookup $1 $2 | sed -n '/Name:/,$p' | grep ^Address | grep -oE '([0-9]{1,3}\.){3}[0-9]{1,3}'
;;
host)
host -t A $1 $2 | grep "has address" | grep -oE '([0-9]{1,3}\.){3}[0-9]{1,3}'
;;
esac
}
check_dns_spoof()
{
# $1 - domain
# $2 - public DNS
echo $1 | "$MDIG" --family=4 >"$DNSCHECK_DIG1"
lookup4 $1 $2 >"$DNSCHECK_DIG2"
# check whether system resolver returns anything other than public DNS
grep -qvFf "$DNSCHECK_DIG2" "$DNSCHECK_DIG1"
}
check_dns_cleanup()
{
rm -f "$DNSCHECK_DIG1" "$DNSCHECK_DIG2" "$DNSCHECK_DIGS" 2>/dev/null
}
check_dns()
{
local C1 C2 dom
echo \* checking DNS
[ -f "$DNSCHECK_DIGS" ] && rm -f "$DNSCHECK_DIGS"
dnstest || {
echo -- DNS is not working. It's either misconfigured or blocked or you don't have inet access.
return 1
}
echo system DNS is working
if find_working_public_dns ; then
echo comparing system resolver to public DNS : $PUBDNS
for dom in $DNSCHECK_DOM; do
if check_dns_spoof $dom $PUBDNS ; then
echo $dom : MISMATCH
echo -- system resolver :
cat "$DNSCHECK_DIG1"
echo -- $PUBDNS :
cat "$DNSCHECK_DIG2"
check_dns_cleanup
echo -- POSSIBLE DNS HIJACK DETECTED. ZAPRET WILL NOT HELP YOU IN CASE DNS IS SPOOFED !!!
echo -- DNS CHANGE OR DNSCRYPT MAY BE REQUIRED
return 1
else
echo $dom : OK
cat "$DNSCHECK_DIG1" >>"$DNSCHECK_DIGS"
fi
done
else
echo no working public DNS was found. looks like public DNS blocked.
for dom in $DNSCHECK_DOM; do echo $dom; done | "$MDIG" --threads=10 --family=4 >"$DNSCHECK_DIGS"
fi
echo checking resolved IP uniqueness for : $DNSCHECK_DOM
echo censor\'s DNS can return equal result for multiple blocked domains.
C1=$(wc -l <"$DNSCHECK_DIGS")
C2=$(sort -u "$DNSCHECK_DIGS" | wc -l)
[ "$C1" -eq 0 ] &&
{
echo -- DNS is not working. It's either misconfigured or blocked or you don't have inet access.
check_dns_cleanup
return 1
}
[ "$C1" = "$C2" ] ||
{
echo system dns resolver has returned equal IPs for some domains checked above \($C1 total, $C2 unique\)
echo non-unique IPs :
sort "$DNSCHECK_DIGS" | uniq -d
echo -- POSSIBLE DNS HIJACK DETECTED. ZAPRET WILL NOT HELP YOU IN CASE DNS IS SPOOFED !!!
echo -- DNSCRYPT MAY BE REQUIRED
check_dns_cleanup
return 1
}
echo all resolved IPs are unique
echo -- DNS looks good
echo -- NOTE this check is Russia targeted. In your country other domains may be blocked.
check_dns_cleanup
return 0
}
unprepare_all()
{
# make sure we are not in a middle state that impacts connectivity
rm -f "$HDRTEMP"
[ -n "$IPV" ] && {
tpws_ipt_unprepare 80
tpws_ipt_unprepare 443
pktws_ipt_unprepare 80
pktws_ipt_unprepare 443
}
ws_kill
}
sigint()
{
echo
echo terminating...
unprepare_all
exitp 1
}
sigpipe()
{
# must not write anything here to stdout
unprepare_all
exit 1
}
check_system
check_prerequisites
require_root
check_dns
ask_params
PID=
NREPORT=
trap sigint INT
trap sigpipe PIPE
for dom in $DOMAINS; do
for IPV in $IPVS; do
configure_ip_version
[ "$ENABLE_HTTP" = 1 ] && check_domain_http $dom
[ "$ENABLE_HTTPS_TLS12" = 1 ] && check_domain_https_tls12 $dom
[ "$ENABLE_HTTPS_TLS13" = 1 ] && check_domain_https_tls13 $dom
done
done
trap - PIPE
trap - INT
echo
echo \* SUMMARY
report_print
exitp 0