Merge pull request #54 from jvehent/jvehent-rework-tomato42-curves-tolerance-5

Jvehent rework tomato42 curves tolerance 5, closes #46

cipherscan

@@ -68,6 +68,10 @@ TIMEOUT=30
 # trust anchors are stored
 CAPATH=""
 SAVECRT=""
+TEST_CURVES="False"
+has_curves="False"
+# openssl formated list of curves that will cause server to select ECC suite
+ecc_ciphers=""
 unset known_certs
 declare -A known_certs
 unset cert_checksums
@@ -106,6 +110,7 @@ Use one of the options below:
 -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
+--[no-]curves       test ECC curves supported by server (req. OpenSSL 1.0.2)
 -v | --verbose      Increase verbosity.
 
 The rest of the arguments will be interpreted as openssl s_client argument.
@@ -128,6 +133,68 @@ debug(){
     fi
 }
 
+# obtain an array of curves supported by openssl
+CURVES=(sect163k1 # K-163
+    sect163r1
+    sect163r2 # B-163
+    sect193r1
+    sect193r2
+    sect233k1 # K-233
+    sect233r1 # B-233
+    sect239k1
+    sect283k1 # K-283
+    sect283r1 # B-283
+    sect409k1 # K-409
+    sect409r1 # B-409
+    sect571k1 # K-571
+    sect571r1 # B-571
+    secp160k1
+    secp160r1
+    secp160r2
+    secp192k1
+    prime192v1 # P-192 secp192r1
+    secp224k1
+    secp224r1 # P-224
+    secp256k1
+    prime256v1 # P-256 secp256r1
+    secp384r1 # P-384
+    secp521r1 # P-521
+    brainpoolP256r1
+    brainpoolP384r1
+    brainpoolP512r1)
+
+# many curves have alternative names, this array provides a mapping to find the IANA
+# name of a curve using its alias
+CURVES_MAP=("sect163k1 K-163"
+      "sect163r2 B-163"
+      "sect233k1 K-233"
+      "sect233r1 B-233"
+      "sect283k1 K-283"
+      "sect283r1 B-283"
+      "sect409k1 K-409"
+      "sect409r1 B-409"
+      "sect571k1 K-571"
+      "sect571r1 B-571"
+      "prime192v1 P-192 secp192r1"
+      "secp224r1 P-224"
+      "prime256v1 P-256 secp256r1"
+      "secp384r1 P-384"
+      "secp521r1 P-521")
+
+get_curve_name() {
+    local identifier=$1
+    for c in "${CURVES_MAP[@]}"; do
+        if [[ "$c" =~ $identifier ]]; then
+            verbose "$c matches identifier $identifier"
+            local map=(${c// / })
+            echo ${map[0]}
+            return
+        fi
+    done
+    echo $identifier
+    return
+}
+
 c_hash() {
     local h=$(${OPENSSLBIN} x509 -hash -noout -in "$1/$2" 2>/dev/null)
     for ((num=0; num<=100; num++)) ; do
@@ -371,6 +438,7 @@ test_cipher_on_target() {
         fi
         cipher=$current_cipher
         pfs=$current_pfs
+        [ -z $pfs ] && pfs="None"
         pubkey=$current_pubkey
         sigalg=$current_sigalg
         trusted=$current_trusted
@@ -388,13 +456,28 @@ test_cipher_on_target() {
 
     # if cipher contains NONE, the cipher wasn't accepted
     elif [ "$cipher" == '(NONE)  ' ]; then
-        result="$cipher $protocols $pubkey $sigalg $trusted $tickethint $ocspstaple $pfs"
+        result="$cipher $protocols $pubkey $sigalg $trusted $tickethint $ocspstaple $pfs $current_curves $curves_ordering"
         verbose "handshake failed, server returned ciphersuite '$result'"
         return 1
 
     # the connection succeeded
     else
-        result="$cipher $protocols $pubkey $sigalg $trusted $tickethint $ocspstaple $pfs"
+        current_curves="None"
+        # if pfs uses ECDH, test supported curves
+        if [[ $pfs =~ ECDH ]]; then
+            has_curves="True"
+            if [ $TEST_CURVES == "True" ]; then
+                test_curves
+                if [ "$ecc_ciphers" != "" ]; then
+                    ecc_ciphers+=":"
+                fi
+                ecc_ciphers+="$cipher"
+            else
+                # resolve the openssl curve to the proper IANA name
+                current_curves="$(get_curve_name $(echo $pfs|cut -d ',' -f2))"
+            fi
+        fi
+        result="$cipher $protocols $pubkey $sigalg $trusted $tickethint $ocspstaple $pfs $current_curves $curves_ordering"
         verbose "handshake succeeded, server returned ciphersuite '$result'"
         return 0
     fi
@@ -455,6 +538,7 @@ display_results_in_terminal() {
     local trusted
     local tickethint
     local ocspstaple
+    local curvesordering
     local different=False
     echo "Target: $TARGET"; echo
     for cipher in "${cipherspref[@]}"; do
@@ -473,6 +557,9 @@ display_results_in_terminal() {
             trusted="${cipher_data[4]}"
             tickethint="${cipher_data[5]}"
             ocspstaple="${cipher_data[6]}"
+            if [[ $TEST_CURVES == "True" && "${cipher_data[9]}" != "" ]]; then
+                curvesordering="${cipher_data[9]}"
+            fi
         else
             if [ "$pubkey" != "${cipher_data[2]}" ]; then
                 different=True
@@ -486,23 +573,33 @@ display_results_in_terminal() {
             if [ "$tickethint" != "${cipher_data[5]}" ]; then
                 different=True
             fi
+            if [ "$ocspstaple" != "${cipher_data[6]}" ]; then
+                different=True
+            fi
+            if [[ "$curvesordering" == "" && "${cipher_data[9]}" != "" ]]; then
+                curvesordering="${cipher_data[9]}"
+            fi
+            if [[ "$curvesordering" != "" && "$curvesordering" != "${cipher_data[9]}" ]]; then
+                different=True
+            fi
         fi
         results=("${results[@]}" "$r")
         ctr=$((ctr+1))
     done
 
+    header="prio ciphersuite protocols"
+    if [ $different == "True" ]; then
+        header+=" pubkey_size signature_algoritm trusted ticket_hint ocsp_staple"
+    fi
+    header+=" pfs"
+    if [ $has_curves == "True" ]; then
+        header+=" curves"
+        if [[ $TEST_CURVES == "True" && $different == "True" ]]; then
+            header+=" curves_ordering"
+        fi
+    fi
     if [ $DOBENCHMARK -eq 1 ]; then
-        if [ $different == "True" ]; then
+        header+=" avg_handshake_microsec"
-            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
@@ -513,8 +610,8 @@ display_results_in_terminal() {
         if [ $different == "True" ]; then
             echo $result|grep -v '(NONE)'
         else
-            # prints priority, ciphersuite, protocols and pfs_keysize
+            # prints priority, ciphersuite, protocols and pfs
-            awk '!/(NONE)/{print $1 " " $2 " " $3 " " $9}' <<<"$result"
+            awk '!/(NONE)/{print $1 " " $2 " " $3 " " $9 " " $10}' <<<"$result"
         fi
     done|column -t
     echo
@@ -532,9 +629,13 @@ display_results_in_terminal() {
         echo "OCSP stapling: not supported"
     fi
     if [[ $serverside == "True" ]]; then
-        echo "Server side cipher ordering"
+        echo "Cipher ordering: server"
     else
-        echo "Client side cipher ordering"
+        echo "Cipher ordering: client"
+    fi
+    if [ $TEST_CURVES == "True" ]; then
+        echo "Curves ordering: $curvesordering"
+        echo "Curves fallback: $fallback_supported"
     fi
 }
 
@@ -557,10 +658,23 @@ display_results_in_json() {
         echo -n "\"ocsp_stapling\":\"${cipher_arr[6]}\","
         pfs="${cipher_arr[7]}"
         [ "$pfs" == "" ] && pfs="None"
-        echo -n "\"pfs\":\"$pfs\"}"
+        echo -n "\"pfs\":\"$pfs\""
+        if [[ "${cipher_arr[0]}" =~ ECDH ]]; then
+            echo -n ","
+            echo -n "\"curves\":[\"${cipher_arr[8]//,/\",\"}\"]"
+            if [ $TEST_CURVES == "True" ]; then
+                echo -n ","
+                echo -n "\"curves_ordering\":\"${cipher_arr[9]}\""
+            fi
+        fi
+        echo -n "}"
         ctr=$((ctr+1))
     done
-    echo ']}'
+    echo -n ']'
+    if [ $TEST_CURVES == "True" ]; then
+        echo -n ",\"curves_fallback\":\"$fallback_supported\""
+    fi
+    echo '}'
 }
 
 test_serverside_ordering() {
@@ -616,6 +730,205 @@ test_serverside_ordering() {
     fi
 }
 
+test_curves() {
+    # "True" if server supports ciphers that don't use ECC at a lower priority
+    local fallback_available="False"
+
+    # return variable: list of curves supported by server, in order
+    current_curves=""
+    # return variable: check if server uses server side or client side ordering
+    # for curves
+    curves_ordering="server"
+
+    local curves=(${CURVES[*]})
+
+    OLDIFS="$IFS"
+    IFS=':'
+    verbose "Will test following curves: ${curves[*]}"
+    IFS="$OLDIFS"
+
+    # prepare the ssl command we'll be using
+    local sslcommand=""
+    sslcommand="$TIMEOUTBIN $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 $current_cipher"
+    # force the TLS to send a TLS1.0 client hello at least, as with SSLv2
+    # ciphers present it will try to send a SSLv2 compatible client hello
+    sslcommand+=" -no_ssl2 -no_ssl3"
+
+    #
+    # here we use the same logic as with detecting cipher suites: first
+    # advertise all curves as supported, then remove curves one by one until we
+    # either get a fallback to a non ECC cipher, we run of curves or server
+    # tries to negotiate a curve we didn't advertise
+    #
+    while [[ ${#curves[@]} -gt 0 ]]; do
+        OLDIFS="$IFS"
+        IFS=':'
+        local test_curves="${curves[*]}"
+        IFS="$OLDIFS"
+        verbose "Testing $test_curves with command $sslcommand"
+
+        ratelimit
+        local tmp=$(echo Q | $sslcommand -curves $test_curves 2>/dev/null)
+        parse_openssl_output <<<"$tmp"
+
+        if [[ -z $current_protocol || $current_cipher == "(NONE)" || $current_cipher == '0000' ]]; then
+            break
+        else
+            # server accepted connection
+            local ephem_data=(${current_pfs//,/ })
+            local cname=""
+            if [[ ${ephem_data[0]} =~ ECDH ]]; then
+                if [ "$current_curves" != "" ]; then
+                    current_curves+=","
+                fi
+                cname="$(get_curve_name ${ephem_data[1]})"
+                verbose "Server selected ${ephem_data[1]}, a.k.a $cname"
+                current_curves+="$cname"
+            fi
+            for id in "${!curves[@]}"; do
+                if [ "$cname" == ${curves[$id]} ]; then
+                    # we know it's supported, remove it from set of offered ones
+                    unset curves[$id]
+                    break
+                fi
+            done
+        fi
+        [ "$OUTPUTFORMAT" == "terminal" ] && [ $DEBUG -lt 1 ] && echo -n '.'
+    done
+
+    # don't penalize servers that will negotiate all curves we know of...
+    if [[ ${#curves[@]} -eq 0 ]]; then
+        fallback_supported="unknown"
+    fi
+
+    #
+    # check if curves ordering is server of client side
+    #
+
+    local tmp_curves=(${current_curves//,/ })
+    verbose "Server supported curves: ${tmp_curves[@]}"
+
+    # server supports just one or none, so it effectively uses server side
+    # ordering (as it dictates what curves client must support)
+    if [ ${#tmp_curves[@]} -lt 2 ]; then
+        curves_ordering="server"
+    else
+        # server supports at least 2 curves, rotate their order, see if
+        # selected changes
+        test_curves=""
+        most_wanted="${tmp_curves[${#tmp_curves[@]}-1]}"
+        for (( i=${#tmp_curves[@]}-1; i>0; i--)); do
+            test_curves+="${tmp_curves[$i]}:"
+        done
+        test_curves+="${tmp_curves[0]}"
+
+        verbose "Testing ordering with $sslcommand -curves $test_curves"
+        ratelimit
+        local tmp=$(echo Q | $sslcommand -curves $test_curves 2>/dev/null)
+        parse_openssl_output <<<"$tmp"
+
+        if [[ -z $current_protocol || $current_cipher == "(NONE)" || $current_cipher == '0000' ]]; then
+                fallback_supported="order-specific"
+                verbose "Server aborted connection"
+        else
+            local ephem_data=(${current_pfs//,/ })
+            verbose "Server selected $current_cipher with $current_pfs"
+            verbose "ephem_data: ${ephem_data[@]}"
+
+            if [[ ${ephem_data[0]} =~ ECDH ]]; then
+                verbose "Server did select ${ephem_data[1]} curve"
+                curves_ordering="inconclusive-${ephem_data[1]}"
+                local cname="$(get_curve_name ${ephem_data[1]})"
+                if [ "$cname" == "$most_wanted" ]; then
+                    curves_ordering="client"
+                else
+                    curves_ordering="server"
+                fi
+            else
+                # some servers downgrade to non ECDH when curve order is changed
+                curves_ordering="inconclusive-noecc"
+            fi
+        fi
+    fi
+}
+
+test_curves_fallback() {
+    # "True" if server supports ciphers that don't use ECC at a lower priority
+    local fallback_available="False"
+    # return variable: whatever a server will fall back to non ECC suite when
+    # client doesn't advertise support for curves the server needs
+    fallback_supported="unknown"
+
+    if [ "$ecc_ciphers" == "" ]; then
+        verbose "No ECC cipher found, can't test curve fallback"
+        return
+    fi
+
+    # prepare the ssl command we'll be using
+    local sslcommand=""
+    sslcommand="$TIMEOUTBIN $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 $ecc_ciphers"
+    # force the TLS to send a TLS1.0 client hello at least, as with SSLv2
+    # ciphers present it will try to send a SSLv2 compatible client hello
+    sslcommand+=" -no_ssl2 -no_ssl3"
+
+    #
+    # here we use the same logic as with detecting cipher suites: first
+    # advertise all curves as supported, then remove curves one by one until we
+    # either get a fallback to a non ECC cipher, we run of curves or server
+    # tries to negotiate a curve we didn't advertise
+    #
+    local curves=(${CURVES[*]})
+    while [[ ${#curves[@]} -gt 0 ]]; do
+        OLDIFS="$IFS"
+        IFS=':'
+        local test_curves="${curves[*]}"
+        IFS="$OLDIFS"
+        verbose "Testing $sslcommand -curves $test_curves"
+
+        ratelimit
+        local tmp=$(echo Q | $sslcommand -curves $test_curves 2>/dev/null)
+        parse_openssl_output <<<"$tmp"
+
+        if [[ -z $current_protocol || $current_cipher == "(NONE)" || $current_cipher == '0000' ]]; then
+            verbose "Curve fallback failed, server refused connection"
+            fallback_supported="False"
+            break
+        else
+            # server accepted connection
+            local ephem_data=(${current_pfs//,/ })
+
+            if [[ ${ephem_data[0]} =~ ECDH ]]; then
+                # we got an ecc connection, remove the curve from the list of testable curves
+                local cname="$(get_curve_name ${ephem_data[1]})"
+                verbose "Server selected curve $cname"
+                for id in "${!curves[@]}"; do
+                    if [ "${curves[id]}" == "$cname" ]; then
+                        unset curves[$id]
+                        break
+                    fi
+                done
+            else
+                verbose "Server fell back to $current_cipher"
+                # ok, we got a fallback
+                fallback_supported="True"
+                break
+            fi
+        fi
+    done
+}
+
 # If no options are given, give usage information and exit (with error code)
 if [ $# -eq 0 ]; then
    usage;
@@ -671,6 +984,14 @@ do
             SAVECRT="$2"
             shift 2
             ;;
+        --curves)
+            TEST_CURVES="True"
+            shift 1
+            ;;
+        --no-curves)
+            TEST_CURVES="False"
+            shift 1
+            ;;
         --) # End of all options
             shift
             break
@@ -711,6 +1032,13 @@ if [ ! -x $OPENSSLBIN ]; then
     fi
 fi
 
+if [ $TEST_CURVES == "True" ]; then
+    if [ ! -z "$($OPENSSLBIN s_client -curves 2>&1|head -1|grep 'unknown option')" ]; then
+        echo "curves testing not available with your version of openssl, disabling it"
+        TEST_CURVES="False"
+    fi
+fi
+
 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))"
@@ -730,6 +1058,10 @@ get_cipher_pref $CIPHERSUITE
 
 test_serverside_ordering
 
+if [[ $TEST_CURVES == "True" ]]; then
+    test_curves_fallback
+fi
+
 if [ "$OUTPUTFORMAT" == "json" ]; then
     display_results_in_json
 else

top1m/parse_results.py

@@ -72,6 +72,9 @@ handshakestats = defaultdict(int)
 keysize = defaultdict(int)
 sigalg = defaultdict(int)
 tickethint = defaultdict(int)
+eccfallback = defaultdict(int)
+eccordering = defaultdict(int)
+ecccurve = defaultdict(int)
 ocspstaple = defaultdict(int)
 dsarsastack = 0
 total = 0
@@ -86,6 +89,9 @@ for r,d,flist in os.walk(path):
         tempdsakeystats = {}
         tempsigstats = {}
         tempticketstats = {}
+        tempeccfallback = "unknown"
+        tempeccordering = "unknown"
+        tempecccurve = {}
         """ supported ciphers by the server under scan """
         tempcipherstats = {}
         ciphertypes = 0
@@ -141,6 +147,21 @@ for r,d,flist in os.walk(path):
             if len(results['ciphersuite']) < 1:
                 continue
 
+            """ save ECC fallback (new format) """
+            if 'curves_fallback' in results:
+                tempeccfallback = results['curves_fallback']
+
+            """ save ECC curve stats (old format) """
+            if 'curve_fallback' in results:
+                tempeccfallback = results['curve_fallback']
+            if 'curve_ordering' in results:
+                tempeccordering = results['curve_ordering']
+            if 'curve' in results:
+                for curve in results['curve']:
+                    tempecccurve[curve] = 1
+                if len(results['curve']) == 1:
+                    tempecccurve[curve + ' Only'] = 1
+
             """ loop over list of ciphers """
             for entry in results['ciphersuite']:
 
@@ -265,6 +286,16 @@ for r,d,flist in os.walk(path):
                         TLS1_1 = True
                     elif protocol == 'TLSv1.2':
                         TLS1_2 = True
+
+                """ save ECC curves stats """
+                if 'curves_ordering' in entry:
+                    tempeccordering = entry['curves_ordering']
+                if 'curves' in entry:
+                    for curve in entry['curves']:
+                        tempecccurve[curve] = 1
+                    if len(entry['curves']) == 1:
+                        tempecccurve[curve + ' Only'] = 1
+
         json_file.close()
 
         """ don't store stats from unusued servers """
@@ -329,6 +360,11 @@ for r,d,flist in os.walk(path):
         for s in tempticketstats:
             tickethint[s] += 1
 
+        eccfallback[tempeccfallback] += 1
+        eccordering[tempeccordering] += 1
+        for s in tempecccurve:
+            ecccurve[s] += 1
+
         if ocsp_stapling is None:
             ocspstaple['Unknown'] += 1
         elif ocsp_stapling:
@@ -518,6 +554,24 @@ for stat in sorted(pfsstats):
         pfspercent = round(pfsstats[stat] / handshakestats['DHE'] * 100, 4)
     sys.stdout.write(stat.ljust(25) + " " + str(pfsstats[stat]).ljust(10) + str(percent).ljust(9) + str(pfspercent) + "\n")
 
+print("\nSupported ECC curves      Count     Percent ")
+print("-------------------------+---------+--------")
+for stat in sorted(ecccurve):
+    percent = round(ecccurve[stat] / total * 100, 4)
+    sys.stdout.write(stat.ljust(25) + " " + str(ecccurve[stat]).ljust(10) + str(percent).ljust(9) + "\n")
+
+print("\nUnsupported curve fallback     Count     Percent ")
+print("------------------------------+---------+--------")
+for stat in sorted(eccfallback):
+    percent = round(eccfallback[stat] / total * 100,4)
+    sys.stdout.write(stat.ljust(30) + " " + str(eccfallback[stat]).ljust(10) + str(percent).ljust(9) + "\n")
+
+print("\nECC curve ordering        Count     Percent ")
+print("-------------------------+---------+--------")
+for stat in sorted(eccordering):
+    percent = round(eccordering[stat] / total * 100, 4)
+    sys.stdout.write(stat.ljust(25) + " " + str(eccordering[stat]).ljust(10) + str(percent).ljust(9) + "\n")
+
 print("\nTLS session ticket hint   Count     Percent ")
 print("-------------------------+---------+--------")
 for stat in natural_sort(tickethint):

top1m/testtop1m.sh

@@ -68,7 +68,7 @@ function scan_host() {
     if [ $? -gt 0 ]; then
         return
     fi
-    ../cipherscan --capath ca_files --saveca --savecrt certs --delay 2 -json -servername $1 $2:443 > results/$1@$2
+    ../cipherscan --capath ca_files --saveca --curves --savecrt certs --delay 2 -json -servername $1 $2:443 > results/$1@$2
 }
 
 function scan_host_no_sni() {
@@ -80,7 +80,7 @@ function scan_host_no_sni() {
     if [ $? -gt 0 ]; then
         return
     fi
-    ../cipherscan --capath ca_files --saveca --savecrt certs --delay 2 -json $1:443 > results/$1
+    ../cipherscan --capath ca_files --saveca --curves --savecrt certs --delay 2 -json $1:443 > results/$1
 }
 
 function scan_hostname() {