Prior to this patch, if the user fails to provide a host:port after
specifying cipherscan options, the script runs sed on an empty variable
(failing with a syntax error) and then asttempts to cipherscan the
target ':443'.
This adds a simple test to ensure that a target was actually provided.
This detects and prevents a specific category of user error, where an
incomplete cipherscan command line ending in an OpenSSL -option results
in cipherscan attempting to scan the target '-option:443'.
This catches instances where the wrong openssl binary is selected (for
instance, if uname -s is neither Darwin nor Linux) and serves as a
simple up-front test to make sure that openssl is working before we
proceed further into the script.
The crude_grep function served only to perform a simple substring check
against the output of openssl -help. So, instead of running the command
each time, iterating its output line by line, and checking for the
substring within it, this simply caches the -help output at startup and
uses $help =~ substring to produce the same result in a single pass.
In cipherscan line 451:
for ((i=0; i<$certificate_count; i=i+1 )); do
^-- SC2004: $/${} is unnecessary on arithmetic variables.
In cipherscan line 603:
cipherbenchms="$((t/1000/$BENCHMARKITER))"
^-- SC2004: $/${} is unnecessary on arithmetic variables.
In cipherscan line 13:
REALPATH=$(dirname $0)
^-- SC2086: Double quote to prevent globbing and word splitting.
In cipherscan line 15:
readlink -f $0 &>/dev/null && REALPATH=$(dirname $(readlink -f $0))
^-- SC2086: Double quote to prevent globbing and word splitting.
^-- SC2046: Quote this to prevent word splitting.
^-- SC2086: Double quote to prevent globbing and word splitting.
In cipherscan line 46:
if [[ -e $(dirname $0)/openssl.cnf ]]; then
^-- SC2086: Double quote to prevent globbing and word splitting.
In cipherscan line 47:
export OPENSSL_CONF="$(dirname $0)/openssl.cnf"
^-- SC2155: Declare and assign separately to avoid masking return values.
^-- SC2086: Double quote to prevent globbing and word splitting.
In cipherscan line 60:
CACERTS="$(dirname $0)/ca-bundle.crt"
^-- SC2086: Double quote to prevent globbing and word splitting.
In cipherscan line 941:
verbose "Server supported curves: ${tmp_curves[@]}"
^-- SC2145: Argument mixes string and array. Use * or separate argument.
In cipherscan line 968:
verbose "ephem_data: ${ephem_data[@]}"
^-- SC2145: Argument mixes string and array. Use * or separate argument.
Bash implements a backwards-compatible sh syntax for [ .. ], which
handles undef variables poorly. Use [[ .. ]] instead, to take full
advantage of the Bash improvements to the comparison brackets.
because subprocess returns `bytes` in Python 3
we need to interpret them to characters, which are needed by json
input and string parsing
fixes#69, #71
buggy servers may choke on large ClientHello's, TLSv1.2 ClientHello's,
etc. try to detect such failures and report them
among tried connections are TLS1.2, TLS1.1, TLS1.0 and SSLv3 with
ability to downgrade to lower protocol versions as well as a size
limited client hello, both TLS1.2 and TLS1.0 version
EXP is self explanatory - export grade
DES-CBC3-MD5 is available only in SSLv2 - not secure
RC4-64-MD5 is also a weakened version (though not marked as export grade)
It's unlikely that there are SSLv2 only servers on the 'net, all
that were detected as such and I've checked actually are intolerant
to low placement of RC4 in cipher order or intolerant to large client
hello in general. In case we detect issues with the server, switch to
reduced cipher set and run the test again that should give better results
for about 3% of hosts
