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mirror of https://github.com/mozilla/cipherscan.git synced 2024-11-22 22:33:40 +01:00
cipherscan/cipherscan
Hubert Kario 3c93cbd6c2 make handling of self signed certs more robust
openssl sometimes will print the filename, then the error, and finish
with OK, matching the colon and space prevents from considering such
certs to be valid
2014-10-04 14:29:36 +02:00

634 lines
21 KiB
Bash
Executable File

#!/usr/bin/env bash
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
# Author: Julien Vehent [:ulfr] - 2013
DOBENCHMARK=0
BENCHMARKITER=30
OPENSSLBIN="$(dirname $0)/openssl"
if [ -z "$CACERTS" ]; then
for f in /etc/pki/tls/certs/ca-bundle.crt /etc/ssl/certs/ca-certificates.crt; do
if [ -e "$f" ]; then
CACERTS="$f"
break
fi
done
fi
if [ ! -e "$CACERTS" ]; then
CACERTS="/etc/ssl/certs/ca-certificates.crt"
fi
if [ ! -e "$CACERTS" ]; then
echo "Warning: CA Certificates not found at $CACERTS, export CACERTS variable with location of your trust anchors" 1>&2
fi
CIPHERSUITE="ALL:COMPLEMENTOFALL:+aRSA"
DEBUG=0
VERBOSE=0
DELAY=0
ALLCIPHERS=0
OUTPUTFORMAT="terminal"
TIMEOUT=10
# place where to put the found intermediate CA certificates and where
# trust anchors are stored
CAPATH=""
SAVECRT=""
unset ok_protocols
declare -A ok_protocols
unset known_certs
declare -A known_certs
unset cert_checksums
declare -A cert_checksums
usage() {
echo -e "usage: $0 [-a|--allciphers] [-b|--benchmark] [--capath directory] [-d|--delay seconds] [-D|--debug] [-j|--json] [--savecrt directory] [-v|--verbose] [-o|--openssl file] [openssl s_client args] <target:port>
usage: $0 -h|--help
$0 attempts to connect to a target site using all the ciphersuites it knows.
Julien Vehent [:ulfr] - https://github.com/jvehent/cipherscan
Port defaults to 443
example: $ $0 www.google.com:443
Use one of the options below:
-a | --allciphers Test all known ciphers individually at the end.
-b | --benchmark Activate benchmark mode.
--capath use CAs from directory, save intermediate certificates there
-d | --delay Pause for n seconds between connections
-D | --debug Output ALL the information.
-h | --help Shows this help text.
-j | --json Output results in JSON format.
-o | --openssl path/to/your/openssl binary you want to use.
--savecrt path where to save untrusted and leaf certificates
-v | --verbose Increase verbosity.
The rest of the arguments will be interpreted as openssl s_client argument.
This enables checking smtp/imap/pop3/ftp/xmpp via -starttls
EXAMPLES: $0 -starttls xmpp jabber.ccc.de:5222
"
}
verbose() {
if [ $VERBOSE != 0 ]; then
echo "$@" >&2
fi
}
debug(){
if [ $DEBUG == 1 ]; then
echo Debug: "$@" >&2
set -evx
fi
}
c_hash() {
local h=$(${OPENSSLBIN} x509 -hash -noout -in "$1/$2" 2>/dev/null)
for num in $(seq 0 100); do
if [[ $1/${h}.${num} -ef $2 ]]; then
# file already linked, ignore
break
fi
if [[ ! -e $1/${h}.${num} ]]; then
# file doesn't exist, create a link
pushd "$1" > /dev/null
ln -s "$2" "${h}.${num}"
popd > /dev/null
break
fi
done
}
# Connect to a target host with the selected ciphersuite
test_cipher_on_target() {
local sslcommand=$@
cipher=""
local cmnd=""
protocols=""
pfs=""
previous_cipher=""
certificates=""
for tls_version in "-ssl2" "-ssl3" "-tls1" "-tls1_1" "-tls1_2"
do
if [[ ${ok_protocols[$tls_version]} -eq 1 ]]; then
continue
fi
# sslv2 client hello doesn't support SNI extension
# in SSLv3 mode OpenSSL just ignores the setting so it's ok
# -status exception is ignored in SSLv2, go figure
if [ "$tls_version" == "-ssl2" ]; then
cmnd=$(sed 's/-servername\ [^ ]*//'<<<$sslcommand)
else
cmnd=$sslcommand
fi
debug echo \"Q\" \| $cmnd $tls_version
local tmp=$(echo "Q" | $cmnd $tls_version 1>/dev/stdout 2>/dev/null)
if grep 'OCSP Response Data' <<<"$tmp" >/dev/null; then
current_ocspstaple="True"
else
current_ocspstaple="False"
fi
# filter out the OCSP server certificate
tmp=$(awk 'BEGIN { pr="yes" } /^======================================/ { if ( pr=="yes" ) pr="no"; else pr="yes" } { if ( pr == "yes" ) print }' <<<"$tmp")
# session metadata
current_cipher=$(awk '/New, / {print $5; exit}' <<<"$tmp")
current_pfs=$(awk '/Server Temp Key/ {print $4$5$6$7; exit}' <<<"$tmp")
current_protocol=$(awk '/^\s+Protocol\s+:/ {print $3; exit}' <<<"$tmp")
current_tickethint=$(awk '/ticket lifetime hint/ {print $6; exit}' <<<"$tmp")
if [ -z $current_tickethint ]; then
current_tickethint=None
fi
# certificate metadata
current_pubkey=$(awk '/Server public key is / {print $5;exit}' <<<"$tmp")
if [ -z $current_pubkey ]; then
current_pubkey=0
fi
current_sigalg=$(${OPENSSLBIN} x509 -noout -text 2>/dev/null <<<"$tmp"|\
awk '/Signature Algorithm/ {print $3; exit}') || current_sigalg="None"
grep 'Verify return code: 0 ' <<<"$tmp" >/dev/null
if [ $? -eq 0 ]; then
current_trusted="True"
else
current_trusted="False"
fi
if [ -z $current_sigalg ]; then
current_sigalg=None
fi
# collect certificate data
current_certificates=""
local certificate_count=$(grep --count -- '-----END CERTIFICATE-----'\
<<<"$tmp")
debug "server presented $certificate_count certificates"
local i
for ((i=0; i<$certificate_count; i=i+1 )); do
# extract i'th certificate
local cert=$(awk -v i=$i 'BEGIN { output=0;n=0 }
/-----BEGIN CERTIFICATE-----/ { output=1 }
output==1 { if (n==i) print }
/-----END CERTIFICATE-----/ { output=0; n++ }' <<<"$tmp")
# put the output to an array instead running awk '{print $1}'
local cksum=($(cksum <<<"$cert"))
# compare the values not just checksums so that eventual collision
# doesn't mess up results
if [[ ${known_certs[$cksum]} == $cert ]]; then
if [ -n "${current_certificates}" ]; then
current_certificates+=","
fi
current_certificates+="\"${cert_checksums[$cksum]}\""
continue
fi
# compute sha256 fingerprint of the certificate
local sha256sum=$(${OPENSSLBIN} x509 -outform DER\
<<<"$cert" 2>/dev/null |\
${OPENSSLBIN} dgst -sha256 -r 2>/dev/null| awk '{print $1}')
# check if it is a CA certificate
local isCA="False"
if ${OPENSSLBIN} x509 -noout -text <<<"$cert" 2>/dev/null |\
grep 'CA:TRUE' >/dev/null; then
isCA="True"
fi
# build trust source for certificate verification
local trust_source=()
if [[ -n $CAPATH ]]; then
trust_source=("-CApath" "$CAPATH")
elif [[ -e $CACERTS ]]; then
trust_source=("-CAfile" "$CACERTS")
fi
# check if the certificate is actually trusted (server may present
# unrelated certificates that are not trusted (including self
# signed ones)
local saved="False"
if ${OPENSSLBIN} verify "${trust_source[@]}" \
-untrusted <(echo "$tmp") <(echo "$cert") 2>/dev/null | \
grep ': OK$' >/dev/null; then
# if the certificate is an intermediate CA it may be useful
# for connecting to servers that are misconfigured so save it
if [[ -n $CAPATH ]] && [[ $isCA == "True" ]]; then
if [[ ! -e "$CAPATH/${sha256sum}.pem" ]]; then
echo "$cert" > "$CAPATH/${sha256sum}.pem"
c_hash "$CAPATH" "${sha256sum}.pem"
fi
saved="True"
fi
fi
if [[ -n $SAVECRT ]] && [[ $saved == "False" ]]; then
if [[ ! -e $SAVECRT/${sha256sum}.pem ]]; then
echo "$cert" > "$SAVECRT/${sha256sum}.pem"
fi
fi
# save the sha sum for reporting
if [ -n "${current_certificates}" ]; then
current_certificates+=","
fi
current_certificates+="\"${sha256sum}\""
known_certs[$cksum]="$cert"
cert_checksums[$cksum]="$sha256sum"
done
debug "current_certificates: $current_certificates"
# parsing finished, report result
if [[ -z "$current_protocol" || "$current_cipher" == '(NONE)' ]]; then
ok_protocols["$tls_version"]=1
# connection failed, try again with next TLS version
continue
else
verbose "connection successful; protocol: $current_protocol, cipher: $current_cipher, previous cipher: $previous_cipher"
fi
# handling of TLSv1.2 only cipher suites
if [ ! -z "$previous_cipher" ] && [ "$previous_cipher" != "$current_cipher" ] && [ "$current_cipher" != "0000" ]; then
unset protocols
fi
previous_cipher=$current_cipher
# connection succeeded, add TLS version to positive results
if [ -z "$protocols" ]; then
protocols=$current_protocol
else
protocols="$protocols,$current_protocol"
fi
cipher=$current_cipher
pfs=$current_pfs
pubkey=$current_pubkey
sigalg=$current_sigalg
trusted=$current_trusted
tickethint=$current_tickethint
ocspstaple=$current_ocspstaple
certificates="$current_certificates"
# grab the cipher and PFS key size
done
# if cipher is empty, that means none of the TLS version worked with
# the current cipher
if [ -z "$cipher" ]; then
verbose "handshake failed, no ciphersuite was returned"
result='ConnectionFailure'
return 2
# if cipher contains NONE, the cipher wasn't accepted
elif [ "$cipher" == '(NONE) ' ]; then
result="$cipher $protocols $pubkey $sigalg $trusted $tickethint $ocspstaple $pfs"
verbose "handshake failed, server returned ciphersuite '$result'"
return 1
# the connection succeeded
else
result="$cipher $protocols $pubkey $sigalg $trusted $tickethint $ocspstaple $pfs"
verbose "handshake succeeded, server returned ciphersuite '$result'"
return 0
fi
}
# Calculate the average handshake time for a specific ciphersuite
bench_cipher() {
local ciphersuite="$1"
local sslcommand="timeout $TIMEOUT $OPENSSLBIN s_client $SCLIENTARGS -connect $TARGET -cipher $ciphersuite"
local t="$(date +%s%N)"
verbose "Benchmarking handshake on '$TARGET' with ciphersuite '$ciphersuite'"
for i in $(seq 1 $BENCHMARKITER); do
debug Connection $i
(echo "Q" | $sslcommand 2>/dev/null 1>/dev/null)
if [ $? -gt 0 ]; then
break
fi
done
# Time interval in nanoseconds
local t="$(($(date +%s%N) - t))"
verbose "Benchmarking done in $t nanoseconds"
# Microseconds
cipherbenchms="$((t/1000/$BENCHMARKITER))"
}
# Connect to the target and retrieve the chosen cipher
# recursively until the connection fails
get_cipher_pref() {
[ "$OUTPUTFORMAT" == "terminal" ] && [ $DEBUG -lt 1 ] && echo -n '.'
local ciphersuite="$1"
local sslcommand="timeout $TIMEOUT $OPENSSLBIN s_client"
if [ -n "$CAPATH" ]; then
sslcommand+=" -CApath $CAPATH -showcerts"
elif [ -e $CACERTS ]; then
sslcommand+=" -CAfile $CACERTS"
fi
sslcommand+=" -status $SCLIENTARGS -connect $TARGET -cipher $ciphersuite"
verbose "Connecting to '$TARGET' with ciphersuite '$ciphersuite'"
test_cipher_on_target "$sslcommand"
local success=$?
# If the connection succeeded with the current cipher, benchmark and store
if [ $success -eq 0 ]; then
cipherspref=("${cipherspref[@]}" "$result")
ciphercertificates=("${ciphercertificates[@]}" "$certificates")
pciph=($(echo $result))
get_cipher_pref "!$pciph:$ciphersuite"
return 0
fi
sleep $DELAY
}
display_results_in_terminal() {
# Display the results
ctr=1
local pubkey
local sigalg
local trusted
local tickethint
local ocspstaple
local different=False
for cipher in "${cipherspref[@]}"; do
pciph=($(echo $cipher))
if [ $DOBENCHMARK -eq 1 ]; then
bench_cipher "$pciph"
r="$ctr $cipher $cipherbenchms"
else
r="$ctr $cipher"
fi
if [ $ctr -eq 1 ]; then
pubkey=$(awk '{print $3}' <<<$cipher)
sigalg=$(awk '{print $4}' <<<$cipher)
trusted=$(awk '{print $5}' <<<$cipher)
tickethint=$(awk '{print $6}' <<<$cipher)
ocspstaple=$(awk '{print $7}' <<<$cipher)
else
if [ "$pubkey" != "$(awk '{print $3}' <<<$cipher)" ]; then
different=True
fi
if [ "$sigalg" != "$(awk '{print $4}' <<<$cipher)" ]; then
different=True
fi
if [ "$trusted" != "$(awk '{print $5}' <<<$cipher)" ]; then
different=True
fi
if [ "$tickethint" != "$(awk '{print $6}' <<<$cipher)" ]; then
different=True
fi
fi
results=("${results[@]}" "$r")
ctr=$((ctr+1))
done
if [ $DOBENCHMARK -eq 1 ]; then
if [ $different == "True" ]; then
header="prio ciphersuite protocols pubkey_size signature_algoritm trusted ticket_hint ocsp_staple pfs_keysize avg_handshake_microsec"
else
header="prio ciphersuite protocols pfs_keysize avg_handshake_microsec"
fi
else
if [ $different == "True" ]; then
header="prio ciphersuite protocols pubkey_size signature_algorithm trusted ticket_hint ocsp_staple pfs_keysize"
else
header="prio ciphersuite protocols pfs_keysize"
fi
fi
ctr=0
for result in "${results[@]}"; do
if [ $ctr -eq 0 ]; then
echo $header
ctr=$((ctr+1))
fi
if [ $different == "True" ]; then
if [[ $(awk '{print $3}' <<< $result) == "SSLv3,TLSv1,TLSv1.1,TLSv1.2" ]]; then
awk '!/(NONE)/{print $1 " " $2 " " "SSLv3-TLSv1.2" " " $4 " " $5 " " $6 " " $7 " " $8 " " $9}' <<<"$result"
else
echo $result|grep -v '(NONE)'
fi
else
# prints priority, ciphersuite, protocols and pfs_keysize
awk '!/(NONE)/{print $1 " " $2 " " $3 " " $9}' <<<"$result"
fi
done|column -t
echo
if [ $different != "True" ]; then
if [ "$trusted" == "True" ]; then
echo "Certificate: trusted, $pubkey bit, $sigalg signature"
else
echo "Certificate: UNTRUSTED, $pubkey bit, $sigalg signature"
fi
echo "TLS ticket lifetime hint: $tickethint"
fi
if [[ $ocspstaple == "True" ]]; then
echo "OCSP stapling: supported"
else
echo "OCSP stapling: not supported"
fi
if [[ $serverside == "True" ]]; then
echo "Server side cipher ordering"
else
echo "Client side cipher ordering"
fi
}
display_results_in_json() {
# Display the results in json
ctr=0
echo -n "{\"target\":\"$TARGET\",\"date\":\"$(date -R)\",\"serverside\":\"${serverside}\",\"ciphersuite\": ["
for cipher in "${cipherspref[@]}"; do
[ $ctr -gt 0 ] && echo -n ','
echo -n "{\"cipher\":\"$(echo $cipher|awk '{print $1}')\","
echo -n "\"protocols\":[\"$(echo $cipher|awk '{print $2}'|sed 's/,/","/g')\"],"
echo -n "\"pubkey\":[\"$(echo $cipher|awk '{print $3}'|sed 's/,/","/g')\"],"
echo -n "\"sigalg\":[\"$(echo $cipher|awk '{print $4}'|sed 's/,/","/g')\"],"
echo -n "\"trusted\":\"$(echo $cipher|awk '{print $5}'|sed 's/,/","/g')\","
if [[ -n $CAPATH ]]; then
echo -n "\"certificates\":[${ciphercertificates[$ctr]}],"
fi
echo -n "\"ticket_hint\":\"$(echo $cipher|awk '{print $6}')\","
echo -n "\"ocsp_stapling\":\"$(echo $cipher|awk '{print $7}')\","
pfs=$(echo $cipher|awk '{print $8}')
[ "$pfs" == "" ] && pfs="None"
echo -n "\"pfs\":\"$pfs\"}"
ctr=$((ctr+1))
done
echo ']}'
}
test_serverside_ordering() {
local ciphersuite=""
local prefered=""
# server supports only one cipher or no ciphers, so it effectively uses server side ordering...
if [[ ${#cipherspref[@]} -lt 2 ]]; then
serverside="True"
return 0
# server supports just two ciphers, so rotate them, that should be enough
elif [[ ${#cipherspref[@]} -eq 2 ]]; then
local cipher=$(awk '{print $1}' <<< ${cipherspref[1]})
prefered="$cipher"
ciphersuite=$cipher
cipher=$(awk '{print $1}' <<< ${cipherspref[0]})
ciphersuite+=":$cipher"
# server supports 3 or more ciphers, rotate all three. This is necessary because google does
# select first client provided cipher, if it is either CDHE-RSA-AES128-GCM-SHA256 or
# ECDHE-RSA-CHACHA20-POLY1305
else
local cipher=$(awk '{print $1}' <<< ${cipherspref[2]})
prefered="$cipher"
ciphersuite="$cipher"
cipher=$(awk '{print $1}' <<< ${cipherspref[1]})
ciphersuite+=":$cipher"
cipher=$(awk '{print $1}' <<< ${cipherspref[0]})
ciphersuite+=":$cipher"
fi
local sslcommand="timeout $TIMEOUT $OPENSSLBIN s_client"
if [ -n "$CAPATH" ]; then
sslcommand+=" -CApath $CAPATH -showcerts"
elif [ -e "$CACERTS" ]; then
sslcommand+=" -CAfile $CACERTS"
fi
sslcommand+=" -status $SCLIENTARGS -connect $TARGET -cipher $ciphersuite"
test_cipher_on_target "$sslcommand"
if [ $? -ne 0 ]; then
serverside="True"
else
local selected=$(awk '{print $1}' <<< $result)
if [[ $selected == $prefered ]]; then
serverside="False"
else
serverside="True"
fi
fi
}
# UNKNOWNOPTIONS=""
while :
do
case $1 in
-h | --help | -\?)
usage
exit 0 # This is not an error, User asked help. Don't do "exit 1"
;;
-o | --openssl)
OPENSSLBIN=$2 # You might want to check if you really got FILE
shift 2
;;
-a | --allciphers)
ALLCIPHERS=1
shift
;;
-v | --verbose)
# Each instance of -v adds 1 to verbosity
VERBOSE=$((VERBOSE+1))
shift
;;
-j | -json | --json | --JSON)
OUTPUTFORMAT="json"
shift
;;
-b | --benchmark)
DOBENCHMARK=1
shift
;;
-D | --debug)
DEBUG=1
shift
;;
-d | --delay)
DELAY=$2
shift 2
;;
--capath)
CAPATH="$2"
shift 2
;;
--savecrt)
SAVECRT="$2"
shift 2
;;
--) # End of all options
shift
break
;;
# -*)
# UNKNOWNOPTIONS=$((UNKNOWNOPTIONS+$1))
# # echo "WARN: Unknown option (ignored): $1" >&2
# shift
# ;;
*) # no more options we understand.
break
;;
esac
done
if [ $VERBOSE != 0 ] ; then
[ -n "$CACERTS" ] && echo "Using trust anchors from $CACERTS"
echo "Loading $($OPENSSLBIN ciphers -v $CIPHERSUITE 2>/dev/null|grep Kx|wc -l) ciphersuites from $(echo -n $($OPENSSLBIN version 2>/dev/null))"
$OPENSSLBIN ciphers ALL 2>/dev/null
fi
# echo paramters left: $@
TEMPTARGET=$(sed -e 's/^.* //'<<<"${@}")
HOST=$(sed -e 's/:.*//'<<<"${TEMPTARGET}")
PORT=$(sed -e 's/.*://'<<<"${TEMPTARGET}")
# Default to https if no port given
if [ "$HOST" = "$PORT" ]; then
PORT=443
fi
debug "host: $HOST"
debug "Port: $PORT"
TARGET=$HOST:$PORT
debug "target: $TARGET"
SCLIENTARGS=$(sed -e s,${TEMPTARGET},,<<<"${@}")
debug "sclientargs: $SCLIENTARGS"
cipherspref=();
ciphercertificates=()
results=()
# Call to the recursive loop that retrieves the cipher preferences
get_cipher_pref $CIPHERSUITE
unset ok_protocols
declare -A ok_protocols
test_serverside_ordering
if [ "$OUTPUTFORMAT" == "json" ]; then
display_results_in_json
else
echo
display_results_in_terminal
fi
# If asked, test every single cipher individually
if [ $ALLCIPHERS -gt 0 ]; then
echo; echo "All accepted ciphersuites"
for c in $($OPENSSLBIN ciphers -v ALL:COMPLEMENTOFALL 2>/dev/null |awk '{print $1}'|sort|uniq); do
r="fail"
osslcommand="timeout $TIMEOUT $OPENSSLBIN s_client $SCLIENTARGS -connect $TARGET -cipher $c"
test_cipher_on_target "$osslcommand"
if [ $? -eq 0 ]; then
r="pass"
fi
echo "$c $r"|awk '{printf "%-35s %s\n",$1,$2}'
debug "Sleeping for $DELAY."
sleep $DELAY
done
fi