diff --git a/cipherscan b/cipherscan
index 8b539ae..21d52c6 100755
--- a/cipherscan
+++ b/cipherscan
@@ -10,16 +10,23 @@
 
 DOBENCHMARK=0
 BENCHMARKITER=30
-REALPATH=$(dirname $0)
+DIRNAMEPATH=$(dirname "$0")
+REALPATH="$DIRNAMEPATH"
 # make sure this doesn't error out when readlink -f isn't available (OSX)
-readlink -f $0 &>/dev/null && REALPATH=$(dirname $(readlink -f $0))
-OPENSSLBIN="${REALPATH}/openssl"
-if [ "$(uname -s)" == "Darwin" ]; then
+readlink -f "$0" &>/dev/null && REALPATH=$(dirname "$(readlink -f "$0")")
+if [[ "$(uname -s)" == "Darwin" ]]; then
     OPENSSLBIN="${REALPATH}/openssl-darwin64"
+else
+    OPENSSLBIN="${REALPATH}/openssl"
+fi
+OPENSSLBINHELP="$($OPENSSLBIN s_client -help 2>&1)"
+if ! [[ $OPENSSLBINHELP =~ -connect ]]; then
+    echo "$OPENSSLBIN s_client doesn't accept the -connect parameter, which is extremely strange; refusing to proceed." 1>&2
+    exit 1
 fi
 
 # cipherscan requires bash4, which doesn't come by default in OSX
-if [ ${BASH_VERSINFO[0]} -lt 4 ]; then
+if [[ ${BASH_VERSINFO[0]} -lt 4 ]]; then
     echo "Bash version 4 is required to run cipherscan."
     echo "Please upgrade your version of bash (ex: brew install bash)."
     exit 1
@@ -28,36 +35,36 @@ fi
 # test that timeout or gtimeout (darwin) are present
 TIMEOUTBIN="$(which timeout)"
 
-if [ "$TIMEOUTBIN" == "" ]; then
+if [[ "$TIMEOUTBIN" == "" ]]; then
     TIMEOUTBIN="$(which gtimeout)"
-    if [ "$TIMEOUTBIN" == "" ]; then
+    if [[ "$TIMEOUTBIN" == "" ]]; then
         echo "neither timeout nor gtimeout are present. install coreutils with {apt-get,yum,brew} install coreutils"
         exit 1
     fi
 fi
 
 # Check for busybox, which has different arguments
-TIMEOUTOUTPUT=$(($TIMEOUTBIN --help) 2>&1)
+TIMEOUTOUTPUT="$($TIMEOUTBIN --help 2>&1)"
 if [[ "$TIMEOUTOUTPUT" =~ BusyBox ]]; then
     TIMEOUTBIN="$TIMEOUTBIN -t"
 fi
 
 # use custom config file to enable GOST ciphers
-if [[ -e $(dirname $0)/openssl.cnf ]]; then
-    export OPENSSL_CONF="$(dirname $0)/openssl.cnf"
+if [[ -e $DIRNAMEPATH/openssl.cnf ]]; then
+    export OPENSSL_CONF="$DIRNAMEPATH/openssl.cnf"
 fi
 
 # find a list of trusted CAs on the local system, or use the provided list
-if [ -z "$CACERTS" ]; then
+if [[ -z "$CACERTS" ]]; then
     for f in /etc/pki/tls/certs/ca-bundle.crt /etc/ssl/certs/ca-certificates.crt; do
-        if [ -e "$f" ]; then
+        if [[ -e "$f" ]]; then
             CACERTS="$f"
             break
         fi
     done
 fi
-if [ ! -e "$CACERTS" ]; then
-    CACERTS="$(dirname $0)/ca-bundle.crt"
+if [[ ! -e "$CACERTS" ]]; then
+    CACERTS="$DIRNAMEPATH/ca-bundle.crt"
 fi
 
 # RSA ciphers are put at the end to force Google servers to accept ECDSA ciphers
@@ -65,68 +72,70 @@ fi
 CIPHERSUITE="ALL:COMPLEMENTOFALL:+aRSA"
 # some servers are intolerant to large client hello, try a shorter list of
 # ciphers with them
-SHORTCIPHERSUITE=('ECDHE-ECDSA-AES128-GCM-SHA256'
-        'ECDHE-RSA-AES128-GCM-SHA256'
-        'ECDHE-RSA-AES256-GCM-SHA384'
-        'ECDHE-ECDSA-AES256-SHA'
-        'ECDHE-ECDSA-AES128-SHA'
-        'ECDHE-RSA-AES128-SHA'
-        'ECDHE-RSA-AES256-SHA'
-        'ECDHE-RSA-DES-CBC3-SHA'
-        'ECDHE-ECDSA-RC4-SHA'
-        'ECDHE-RSA-RC4-SHA'
-        'DHE-RSA-AES128-SHA'
-        'DHE-DSS-AES128-SHA'
-        'DHE-RSA-CAMELLIA128-SHA'
-        'DHE-RSA-AES256-SHA'
-        'DHE-DSS-AES256-SHA'
-        'DHE-RSA-CAMELLIA256-SHA'
-        'EDH-RSA-DES-CBC3-SHA'
-        'AES128-SHA'
-        'CAMELLIA128-SHA'
-        'AES256-SHA'
-        'CAMELLIA256-SHA'
-        'DES-CBC3-SHA'
-        'RC4-SHA'
-        'RC4-MD5')
+SHORTCIPHERSUITE=(
+    'ECDHE-ECDSA-AES128-GCM-SHA256'
+    'ECDHE-RSA-AES128-GCM-SHA256'
+    'ECDHE-RSA-AES256-GCM-SHA384'
+    'ECDHE-ECDSA-AES256-SHA'
+    'ECDHE-ECDSA-AES128-SHA'
+    'ECDHE-RSA-AES128-SHA'
+    'ECDHE-RSA-AES256-SHA'
+    'ECDHE-RSA-DES-CBC3-SHA'
+    'ECDHE-ECDSA-RC4-SHA'
+    'ECDHE-RSA-RC4-SHA'
+    'DHE-RSA-AES128-SHA'
+    'DHE-DSS-AES128-SHA'
+    'DHE-RSA-CAMELLIA128-SHA'
+    'DHE-RSA-AES256-SHA'
+    'DHE-DSS-AES256-SHA'
+    'DHE-RSA-CAMELLIA256-SHA'
+    'EDH-RSA-DES-CBC3-SHA'
+    'AES128-SHA'
+    'CAMELLIA128-SHA'
+    'AES256-SHA'
+    'CAMELLIA256-SHA'
+    'DES-CBC3-SHA'
+    'RC4-SHA'
+    'RC4-MD5'
+)
 # as some servers are intolerant to large client hello's (or ones that have
 # RC4 ciphers below position 64), use the following for cipher testing in case
 # of problems
 FALLBACKCIPHERSUITE=(
-        'ECDHE-RSA-AES128-GCM-SHA256'
-        'ECDHE-RSA-AES128-SHA256'
-        'ECDHE-RSA-AES128-SHA'
-        'ECDHE-RSA-DES-CBC3-SHA'
-        'ECDHE-RSA-RC4-SHA'
-        'DHE-RSA-AES128-SHA'
-        'DHE-DSS-AES128-SHA'
-        'DHE-RSA-CAMELLIA128-SHA'
-        'DHE-RSA-AES256-SHA'
-        'DHE-DSS-AES256-SHA'
-        'DHE-RSA-CAMELLIA256-SHA'
-        'EDH-RSA-DES-CBC3-SHA'
-        'AES128-SHA'
-        'CAMELLIA128-SHA'
-        'AES256-SHA'
-        'CAMELLIA256-SHA'
-        'DES-CBC3-SHA'
-        'RC4-SHA'
-        'RC4-MD5'
-        'SEED-SHA'
-        'IDEA-CBC-SHA'
-        'IDEA-CBC-MD5'
-        'RC2-CBC-MD5'
-        'DES-CBC3-MD5'
-        'EXP1024-DHE-DSS-DES-CBC-SHA'
-        'EDH-RSA-DES-CBC-SHA'
-        'EXP1024-DES-CBC-SHA'
-        'DES-CBC-MD5'
-        'EXP1024-RC4-SHA'
-        'EXP-EDH-RSA-DES-CBC-SHA'
-        'EXP-DES-CBC-SHA'
-        'EXP-RC2-CBC-MD5'
-        'EXP-RC4-MD5'
-        )
+    'ECDHE-RSA-AES128-GCM-SHA256'
+    'ECDHE-RSA-AES128-SHA256'
+    'ECDHE-RSA-AES128-SHA'
+    'ECDHE-RSA-DES-CBC3-SHA'
+    'ECDHE-RSA-RC4-SHA'
+    'DHE-RSA-AES128-SHA'
+    'DHE-DSS-AES128-SHA'
+    'DHE-RSA-CAMELLIA128-SHA'
+    'DHE-RSA-AES256-SHA'
+    'DHE-DSS-AES256-SHA'
+    'DHE-RSA-CAMELLIA256-SHA'
+    'EDH-RSA-DES-CBC3-SHA'
+    'AES128-SHA'
+    'CAMELLIA128-SHA'
+    'AES256-SHA'
+    'CAMELLIA256-SHA'
+    'DES-CBC3-SHA'
+    'RC4-SHA'
+    'RC4-MD5'
+    'SEED-SHA'
+    'IDEA-CBC-SHA'
+    'IDEA-CBC-MD5'
+    'RC2-CBC-MD5'
+    'DES-CBC3-MD5'
+    'EXP1024-DHE-DSS-DES-CBC-SHA'
+    'EDH-RSA-DES-CBC-SHA'
+    'EXP1024-DES-CBC-SHA'
+    'DES-CBC-MD5'
+    'EXP1024-RC4-SHA'
+    'EXP-EDH-RSA-DES-CBC-SHA'
+    'EXP-DES-CBC-SHA'
+    'EXP-RC2-CBC-MD5'
+    'EXP-RC4-MD5'
+)
 DEBUG=0
 VERBOSE=0
 DELAY=0
@@ -192,65 +201,69 @@ EXAMPLES: $0 -starttls xmpp jabber.ccc.de:5222
 }
 
 verbose() {
-    if [ $VERBOSE != 0 ]; then
+    if [[ $VERBOSE != 0 ]]; then
         echo "$@" >&2
     fi
 }
 
 debug(){
-    if [ $DEBUG == 1 ]; then
+    if [[ $DEBUG == 1 ]]; then
         echo Debug: "$@" >&2
 	set -evx
     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)
+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")
+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
@@ -275,26 +288,20 @@ c_hash() {
         fi
         if [[ ! -e $1/${h}.${num} ]]; then
             # file doesn't exist, create a link
-            pushd "$1" > /dev/null
-            ln -s "$2" "${h}.${num}"
+            if pushd "$1" > /dev/null; then
+                ln -s "$2" "${h}.${num}"
+            else
+                echo "'pushd $1' failed unexpectedly, refusing to proceed" 1>&2
+                exit 1
+            fi
             popd > /dev/null
             break
         fi
     done
 }
 
-crude_grep() {
-    while read line; do
-        if [[ $line =~ $1 ]]; then
-            return 0
-        fi
-    done
-    return 1
-}
-
 check_option_support() {
-    $OPENSSLBIN s_client -help 2>&1 | crude_grep "$1"
-    return $?
+    [[ $OPENSSLBINHELP =~ "$1" ]]
 }
 
 parse_openssl_output() {
@@ -416,7 +423,7 @@ test_cipher_on_target() {
         # 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 [ "$tls_version" == "-ssl2" ]; then
+        if [[ "$tls_version" == "-ssl2" ]]; then
             if [[ "$sslcommand" =~ (.*)(-servername\ [^ ]*)(.*) ]]; then
                 cmnd="${BASH_REMATCH[1]} ${BASH_REMATCH[3]}"
             else
@@ -438,7 +445,7 @@ test_cipher_on_target() {
         local certificate_count=$certs_found
         debug "server presented $certificate_count certificates"
         local i
-        for ((i=0; i<$certificate_count; i=i+1 )); do
+        for ((i=0; i<certificate_count; i=i+1 )); do
 
             # extract i'th certificate
             local cert="${current_raw_certificates[$i]}"
@@ -447,7 +454,7 @@ test_cipher_on_target() {
             # 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
+                if [[ -n "${current_certificates}" ]]; then
                     current_certificates+=","
                 fi
                 current_certificates+="\"${cert_checksums[$cksum]}\""
@@ -498,7 +505,7 @@ test_cipher_on_target() {
                 fi
             fi
             # save the sha sum for reporting
-            if [ -n "${current_certificates}" ]; then
+            if [[ -n "${current_certificates}" ]]; then
                 current_certificates+=","
             fi
             current_certificates+="\"${sha256sum}\""
@@ -515,20 +522,20 @@ test_cipher_on_target() {
             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" ] && [ "$current_cipher" != "0000" ]; then
+        if [[ ! -z "$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 "$protocols" ]; then
+        if [[ -z "$protocols" ]]; then
             protocols=$current_protocol
         else
             protocols="$protocols,$current_protocol"
         fi
         cipher=$current_cipher
         pfs=$current_pfs
-        [ -z $pfs ] && pfs="None"
+        [[ -z $pfs ]] && pfs="None"
         pubkey=$current_pubkey
         sigalg=$current_sigalg
         trusted=$current_trusted
@@ -539,13 +546,13 @@ test_cipher_on_target() {
     done
     # if cipher is empty, that means none of the TLS version worked with
     # the current cipher
-    if [ -z "$cipher" ]; then
+    if [[ -z "$cipher" ]]; then
         verbose "handshake failed, no ciphersuite was returned"
         result='ConnectionFailure'
         return 2
 
     # if cipher contains NONE, the cipher wasn't accepted
-    elif [ "$cipher" == '(NONE)  ' ]; then
+    elif [[ "$cipher" == '(NONE)  ' ]]; then
         result="$cipher $protocols $pubkey $sigalg $trusted $tickethint $ocspstaple $pfs $current_curves $curves_ordering"
         verbose "handshake failed, server returned ciphersuite '$result'"
         return 1
@@ -556,9 +563,9 @@ test_cipher_on_target() {
         # if pfs uses ECDH, test supported curves
         if [[ $pfs =~ ECDH ]]; then
             has_curves="True"
-            if [ $TEST_CURVES == "True" ]; then
+            if [[ $TEST_CURVES == "True" ]]; then
                 test_curves
-                if [ "$ecc_ciphers" != "" ]; then
+                if [[ "$ecc_ciphers" != "" ]]; then
                     ecc_ciphers+=":"
                 fi
                 ecc_ciphers+="$cipher"
@@ -582,7 +589,7 @@ bench_cipher() {
     for i in $(seq 1 $BENCHMARKITER); do
         debug Connection $i
         (echo "Q" | $sslcommand 2>/dev/null 1>/dev/null)
-        if [ $? -gt 0 ]; then
+        if [[ $? -gt 0 ]]; then
             break
         fi
     done
@@ -590,19 +597,19 @@ bench_cipher() {
     local t="$(($(date +%s%N) - t))"
     verbose "Benchmarking done in $t nanoseconds"
     # Microseconds
-    cipherbenchms="$((t/1000/$BENCHMARKITER))"
+    cipherbenchms="$((t/1000/BENCHMARKITER))"
 }
 
 # Connect to the target and retrieve the chosen cipher
 # recursively until the connection fails
 get_cipher_pref() {
-    [ "$OUTPUTFORMAT" == "terminal" ] && [ $DEBUG -lt 1 ] && echo -n '.'
+    [[ "$OUTPUTFORMAT" == "terminal" ]] && [[ $DEBUG -lt 1 ]] && echo -n '.'
     local ciphersuite="$1"
 
     local sslcommand="$TIMEOUTBIN $TIMEOUT $OPENSSLBIN s_client"
-    if [ -n "$CAPATH" ]; then
+    if [[ -n "$CAPATH" ]]; then
         sslcommand+=" -CApath $CAPATH -showcerts"
-    elif [ -e $CACERTS ]; then
+    elif [[ -e $CACERTS ]]; then
         sslcommand+=" -CAfile $CACERTS"
     fi
     sslcommand+=" -status $SCLIENTARGS -connect $TARGET -cipher $ciphersuite"
@@ -611,7 +618,7 @@ get_cipher_pref() {
     test_cipher_on_target "$sslcommand"
     local success=$?
     # If the connection succeeded with the current cipher, benchmark and store
-    if [ $success -eq 0 ]; then
+    if [[ $success -eq 0 ]]; then
         cipherspref=("${cipherspref[@]}" "$result")
         ciphercertificates=("${ciphercertificates[@]}" "$certificates")
         pciph=($result)
@@ -634,14 +641,14 @@ display_results_in_terminal() {
     for cipher in "${cipherspref[@]}"; do
         # get first in array
         pciph=($cipher)
-        if [ $DOBENCHMARK -eq 1 ]; then
+        if [[ $DOBENCHMARK -eq 1 ]]; then
             bench_cipher "$pciph"
             r="$ctr $cipher $cipherbenchms"
         else
             r="$ctr $cipher"
         fi
         local cipher_data=($cipher)
-        if [ $ctr -eq 1 ]; then
+        if [[ $ctr -eq 1 ]]; then
             pubkey="${cipher_data[2]}"
             sigalg="${cipher_data[3]}"
             trusted="${cipher_data[4]}"
@@ -651,19 +658,19 @@ display_results_in_terminal() {
                 curvesordering="${cipher_data[9]}"
             fi
         else
-            if [ "$pubkey" != "${cipher_data[2]}" ]; then
+            if [[ "$pubkey" != "${cipher_data[2]}" ]]; then
                 different=True
             fi
-            if [ "$sigalg" != "${cipher_data[3]}" ]; then
+            if [[ "$sigalg" != "${cipher_data[3]}" ]]; then
                 different=True
             fi
-            if [ "$trusted" != "${cipher_data[4]}" ]; then
+            if [[ "$trusted" != "${cipher_data[4]}" ]]; then
                 different=True
             fi
-            if [ "$tickethint" != "${cipher_data[5]}" ]; then
+            if [[ "$tickethint" != "${cipher_data[5]}" ]]; then
                 different=True
             fi
-            if [ "$ocspstaple" != "${cipher_data[6]}" ]; then
+            if [[ "$ocspstaple" != "${cipher_data[6]}" ]]; then
                 different=True
             fi
             if [[ "$curvesordering" == "" && "${cipher_data[9]}" != "" ]]; then
@@ -678,26 +685,26 @@ display_results_in_terminal() {
     done
 
     header="prio ciphersuite protocols"
-    if [ $different == "True" ]; then
+    if [[ $different == "True" ]]; then
         header+=" pubkey_size signature_algoritm trusted ticket_hint ocsp_staple"
     fi
     header+=" pfs"
-    if [ $has_curves == "True" ]; then
+    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 [[ $DOBENCHMARK -eq 1 ]]; then
         header+=" avg_handshake_microsec"
     fi
     ctr=0
     for result in "${results[@]}"; do
-        if [ $ctr -eq 0 ]; then
+        if [[ $ctr -eq 0 ]]; then
             echo $header
             ctr=$((ctr+1))
         fi
-        if [ $different == "True" ]; then
+        if [[ $different == "True" ]]; then
             echo $result|grep -v '(NONE)'
         else
             # prints priority, ciphersuite, protocols and pfs
@@ -705,8 +712,8 @@ display_results_in_terminal() {
         fi
     done|column -t
     echo
-    if [ $different != "True" ]; then
-        if [ "$trusted" == "True" ]; then
+    if [[ $different != "True" ]]; then
+        if [[ "$trusted" == "True" ]]; then
             echo "Certificate: trusted, $pubkey bit, $sigalg signature"
         else
             echo "Certificate: UNTRUSTED, $pubkey bit, $sigalg signature"
@@ -723,7 +730,7 @@ display_results_in_terminal() {
     else
         echo "Cipher ordering: client"
     fi
-    if [ $TEST_CURVES == "True" ]; then
+    if [[ $TEST_CURVES == "True" ]]; then
         echo "Curves ordering: $curvesordering"
         echo "Curves fallback: $fallback_supported"
     fi
@@ -746,7 +753,7 @@ display_results_in_json() {
     echo -n "{\"target\":\"$TARGET\",\"utctimestamp\":\"$(date -u '+%FT%T.0Z')\",\"serverside\":\"${serverside}\",\"ciphersuite\": ["
     for cipher in "${cipherspref[@]}"; do
         local cipher_arr=($cipher)
-        [ $ctr -gt 0 ] && echo -n ','
+        [[ $ctr -gt 0 ]] && echo -n ','
         echo -n "{\"cipher\":\"${cipher_arr[0]}\","
         echo -n "\"protocols\":[\"${cipher_arr[1]//,/\",\"}\"],"
         echo -n "\"pubkey\":[\"${cipher_arr[2]//,/\",\"}\"],"
@@ -758,12 +765,12 @@ display_results_in_json() {
         echo -n "\"ticket_hint\":\"${cipher_arr[5]}\","
         echo -n "\"ocsp_stapling\":\"${cipher_arr[6]}\","
         pfs="${cipher_arr[7]}"
-        [ "$pfs" == "" ] && pfs="None"
+        [[ "$pfs" == "" ]] && pfs="None"
         echo -n "\"pfs\":\"$pfs\""
         if [[ "${cipher_arr[0]}" =~ ECDH ]]; then
             echo -n ","
             echo -n "\"curves\":[\"${cipher_arr[8]//,/\",\"}\"]"
-            if [ $TEST_CURVES == "True" ]; then
+            if [[ $TEST_CURVES == "True" ]]; then
                 echo -n ","
                 echo -n "\"curves_ordering\":\"${cipher_arr[9]}\""
             fi
@@ -772,14 +779,14 @@ display_results_in_json() {
         ctr=$((ctr+1))
     done
     echo -n ']'
-    if [ $TEST_CURVES == "True" ]; then
+    if [[ $TEST_CURVES == "True" ]]; then
         echo -n ",\"curves_fallback\":\"$fallback_supported\""
     fi
     echo -n ',"configs":{'
     ctr=0
     for test_name in "${!tls_tolerance[@]}"; do
         local result=(${tls_tolerance[$test_name]})
-        [ $ctr -gt 0 ] && echo -n ","
+        [[ $ctr -gt 0 ]] && echo -n ","
         echo -n "\"$test_name\":{"
         if [[ ${result[0]} == "False" ]]; then
             echo -n "\"tolerant\":\"False\""
@@ -826,15 +833,15 @@ test_serverside_ordering() {
     fi
 
     local sslcommand="$TIMEOUTBIN $TIMEOUT $OPENSSLBIN s_client"
-    if [ -n "$CAPATH" ]; then
+    if [[ -n "$CAPATH" ]]; then
         sslcommand+=" -CApath $CAPATH -showcerts"
-    elif [ -e "$CACERTS" ]; then
+    elif [[ -e "$CACERTS" ]]; then
         sslcommand+=" -CAfile $CACERTS"
     fi
     sslcommand+=" -status $SCLIENTARGS -connect $TARGET -cipher $ciphersuite"
 
     test_cipher_on_target "$sslcommand"
-    if [ $? -ne 0 ]; then
+    if [[ $? -ne 0 ]]; then
         serverside="True"
     else
         local selected=($result)
@@ -847,9 +854,6 @@ test_serverside_ordering() {
 }
 
 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
@@ -866,9 +870,9 @@ test_curves() {
     # prepare the ssl command we'll be using
     local sslcommand=""
     sslcommand="$TIMEOUTBIN $TIMEOUT $OPENSSLBIN s_client"
-    if [ -n "$CAPATH" ]; then
+    if [[ -n "$CAPATH" ]]; then
         sslcommand+=" -CApath $CAPATH -showcerts"
-    elif [ -e "$CACERTS" ]; then
+    elif [[ -e "$CACERTS" ]]; then
         sslcommand+=" -CAfile $CACERTS"
     fi
     sslcommand+=" -status $SCLIENTARGS -connect $TARGET -cipher $current_cipher"
@@ -900,7 +904,7 @@ test_curves() {
             local ephem_data=(${current_pfs//,/ })
             local cname=""
             if [[ ${ephem_data[0]} =~ ECDH ]]; then
-                if [ "$current_curves" != "" ]; then
+                if [[ "$current_curves" != "" ]]; then
                     current_curves+=","
                 fi
                 cname="$(get_curve_name ${ephem_data[1]})"
@@ -908,14 +912,14 @@ test_curves() {
                 current_curves+="$cname"
             fi
             for id in "${!curves[@]}"; do
-                if [ "$cname" == ${curves[$id]} ]; then
+                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" ] && [ $DEBUG -lt 1 ] && echo -n '.'
+        [[ "$OUTPUTFORMAT" == "terminal" ]] && [[ $DEBUG -lt 1 ]] && echo -n '.'
     done
 
     # don't penalize servers that will negotiate all curves we know of...
@@ -928,11 +932,11 @@ test_curves() {
     #
 
     local tmp_curves=(${current_curves//,/ })
-    verbose "Server supported curves: ${tmp_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
+    if [[ ${#tmp_curves[@]} -lt 2 ]]; then
         curves_ordering="server"
     else
         # server supports at least 2 curves, rotate their order, see if
@@ -955,13 +959,13 @@ test_curves() {
         else
             local ephem_data=(${current_pfs//,/ })
             verbose "Server selected $current_cipher with $current_pfs"
-            verbose "ephem_data: ${ephem_data[@]}"
+            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" == "$most_wanted" ]; then
+                if [[ "$cname" == "$most_wanted" ]]; then
                     curves_ordering="client"
                 else
                     curves_ordering="server"
@@ -975,13 +979,11 @@ test_curves() {
 }
 
 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 [ "$ecc_ciphers" == "" ]; then
+    if [[ "$ecc_ciphers" == "" ]]; then
         verbose "No ECC cipher found, can't test curve fallback"
         return
     fi
@@ -989,9 +991,9 @@ test_curves_fallback() {
     # prepare the ssl command we'll be using
     local sslcommand=""
     sslcommand="$TIMEOUTBIN $TIMEOUT $OPENSSLBIN s_client"
-    if [ -n "$CAPATH" ]; then
+    if [[ -n "$CAPATH" ]]; then
         sslcommand+=" -CApath $CAPATH -showcerts"
-    elif [ -e "$CACERTS" ]; then
+    elif [[ -e "$CACERTS" ]]; then
         sslcommand+=" -CAfile $CACERTS"
     fi
     sslcommand+=" -status $SCLIENTARGS -connect $TARGET -cipher $ecc_ciphers"
@@ -1030,7 +1032,7 @@ test_curves_fallback() {
                 local cname="$(get_curve_name ${ephem_data[1]})"
                 verbose "Server selected curve $cname"
                 for id in "${!curves[@]}"; do
-                    if [ "${curves[id]}" == "$cname" ]; then
+                    if [[ "${curves[id]}" == "$cname" ]]; then
                         unset curves[$id]
                         break
                     fi
@@ -1083,9 +1085,9 @@ test_tls_tolerance() {
         # cipher string and no options are specified)
         #
         local sslcommand="$TIMEOUTBIN $TIMEOUT $OPENSSLBIN s_client"
-        if [ -n "$CAPATH" ]; then
+        if [[ -n "$CAPATH" ]]; then
             sslcommand+=" -CApath $CAPATH -showcerts"
-        elif [ -e "$CACERTS" ]; then
+        elif [[ -e "$CACERTS" ]]; then
             sslcommand+=" -CAfile $CACERTS"
         fi
         sslcommand+=" -connect $TARGET -cipher $CIPHERSUITE"
@@ -1111,9 +1113,9 @@ test_tls_tolerance() {
         IFS="$OLDIFS"
 
         local sslcommand="$TIMEOUTBIN $TIMEOUT $OPENSSLBIN s_client"
-        if [ -n "$CAPATH" ]; then
+        if [[ -n "$CAPATH" ]]; then
             sslcommand+=" -CApath $CAPATH -showcerts"
-        elif [ -e "$CACERTS" ]; then
+        elif [[ -e "$CACERTS" ]]; then
             sslcommand+=" -CAfile $CACERTS"
         fi
         sslcommand+=" -connect $TARGET -cipher $ciphers"
@@ -1185,9 +1187,9 @@ test_tls_tolerance() {
         IFS="$OLDIFS"
 
         local sslcommand="$TIMEOUTBIN $TIMEOUT $OPENSSLBIN s_client"
-        if [ -n "$CAPATH" ]; then
+        if [[ -n "$CAPATH" ]]; then
             sslcommand+=" -CApath $CAPATH -showcerts"
-        elif [ -e "$CACERTS" ]; then
+        elif [[ -e "$CACERTS" ]]; then
             sslcommand+=" -CAfile $CACERTS"
         fi
         sslcommand+=" $SCLIENTARGS -connect $TARGET -cipher $ciphers:!SSLv2"
@@ -1269,8 +1271,8 @@ test_tls_tolerance() {
 }
 
 # If no options are given, give usage information and exit (with error code)
-if [ $# -eq 0 ]; then
-   usage;
+if [[ $# -eq 0 ]]; then
+   usage
    exit 1
 fi
 
@@ -1353,7 +1355,7 @@ HOST=$(sed -e 's/:.*//'<<<"${TEMPTARGET}")
 PORT=$(sed -e 's/.*://'<<<"${TEMPTARGET}")
 
 # Default to https if no port given
-if [ "$HOST" = "$PORT" ]; then
+if [[ "$HOST" = "$PORT" ]]; then
     PORT=443
 fi
 
@@ -1364,22 +1366,22 @@ TARGET=$HOST:$PORT
 debug "target: $TARGET"
 
 # test our openssl is usable
-if [ ! -x $OPENSSLBIN ]; then
+if [[ ! -x $OPENSSLBIN ]]; then
     OPENSSLBIN=$(which openssl)
-    if [ "$OUTPUTFORMAT" == "terminal" ]; then
+    if [[ "$OUTPUTFORMAT" == "terminal" ]]; then
         echo "custom openssl not executable, falling back to system one from $OPENSSLBIN"
     fi
 fi
 
-if [ $TEST_CURVES == "True" ]; then
-    if [ ! -z "$($OPENSSLBIN s_client -curves 2>&1|head -1|grep 'unknown option')" ]; then
+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"
+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))"
          $OPENSSLBIN ciphers ALL 2>/dev/null
 fi
@@ -1388,7 +1390,7 @@ SCLIENTARGS=$(sed -e s,${TEMPTARGET},,<<<"${@}")
 debug "sclientargs: $SCLIENTARGS"
 
 
-cipherspref=();
+cipherspref=()
 ciphercertificates=()
 results=()
 
@@ -1419,7 +1421,7 @@ if [[ $TEST_CURVES == "True" ]]; then
     test_curves_fallback
 fi
 
-if [ "$OUTPUTFORMAT" == "json" ]; then
+if [[ "$OUTPUTFORMAT" == "json" ]]; then
     display_results_in_json
 else
     echo
@@ -1427,13 +1429,13 @@ else
 fi
 
 # If asked, test every single cipher individually
-if [ $ALLCIPHERS -gt 0 ]; then
+if [[ $ALLCIPHERS -gt 0 ]]; then
     echo; echo "All accepted ciphersuites"
     for c in $($OPENSSLBIN ciphers -v ALL:COMPLEMENTOFALL 2>/dev/null |awk '{print $1}'|sort|uniq); do
         r="fail"
         osslcommand="$TIMEOUTBIN $TIMEOUT $OPENSSLBIN s_client $SCLIENTARGS -connect $TARGET -cipher $c"
         test_cipher_on_target "$osslcommand"
-        if [ $? -eq 0 ]; then
+        if [[ $? -eq 0 ]]; then
             r="pass"
         fi
         echo "$c $r"|awk '{printf "%-35s %s\n",$1,$2}'