Published on March 9th, 2016 📆 | 6974 Views ⚑0
testssl.sh — Testing TLS/SSL encryption
testssl.sh is a free command line tool which checks a server’s service on any port for the support of TLS/SSL ciphers, protocols as well as some cryptographic flaws. It’s designed to provide clear output in any case.
Testing TLS/SSL encryption: testssl.sh
- Clear output: you can tell easily whether anything is good or bad
- Ease of installation: It works for Linux, Darwin, FreeBSD and MSYS2/Cygwin out of the box: no need to install or configure something, no gems, CPAN, pip or the like.
- Flexibility: You can test any SSL/TLS enabled and STARTTLS service, not only webservers at port 443
- Toolbox: Several command line options help you to run YOUR test and configure YOUR output
- Reliability: features are tested thoroughly
- Verbosity: If a particular check cannot be performed because of a missing capability on your client side, you’ll get a warning
- Privacy: It’s only you who sees the result, not a third party
- Freedom: It’s 100% open source. You can look at the code, see what’s going on and you can change it. Heck, even the development is open (github)
It is working on every Linux distribution out of the box with some limitations of disabled features from the openssl client — some workarounds are done with bash-socket-based checks. It also works on BSD and other Unices out of the box, supposed they have
/bin/bash and standard tools like sed and awk installed. MacOS X and Windows (using MSYS2 or cygwin) work too. OpenSSL version >= 1 is a must. OpenSSL version >= 1.0.2 is needed for better LOGJAM checks and to display bit strengths for key exchanges.
The normal use case is probably just testssl.sh <hostname>:
userid@somehost:~ % testssl.sh testssl.sh <options> -h, --help what you're looking at -b, --banner displays banner + version of testssl.sh -v, --version same as previous -V, --local pretty print all local ciphers -V, --local <pattern> which local ciphers with <pattern> are available? (if pattern not a number: word match) testssl.sh <options> URI ("testssl.sh URI" does everything except -E) -e, --each-cipher checks each local cipher remotely -E, --cipher-per-proto checks those per protocol -f, --ciphers checks common cipher suites -p, --protocols checks TLS/SSL protocols -S, --server_defaults displays the servers default picks and certificate info -P, --preference displays the servers picks: protocol+cipher -y, --spdy, --npn checks for SPDY/NPN -x, --single-cipher <pattern> tests matched <pattern> of ciphers (if <pattern> not a number: word match) -U, --vulnerable tests all vulnerabilities -B, --heartbleed tests for heartbleed vulnerability -I, --ccs, --ccs-injection tests for CCS injection vulnerability -R, --renegotiation tests for renegotiation vulnerabilities -C, --compression, --crime tests for CRIME vulnerability -T, --breach tests for BREACH vulnerability -O, --poodle tests for POODLE (SSL) vulnerability -Z, --tls-fallback checks TLS_FALLBACK_SCSV mitigation -F, --freak tests for FREAK vulnerability -A, --beast tests for BEAST vulnerability -J, --logjam tests for LOGJAM vulnerability -s, --pfs, --fs,--nsa checks (perfect) forward secrecy settings -4, --rc4, --appelbaum which RC4 ciphers are being offered? -H, --header, --headers tests HSTS, HPKP, server/app banner, security headers, cookie, reverse proxy, IPv4 address special invocations: -t, --starttls <protocol> does a default run against a STARTTLS enabled <protocol> --xmpphost <to_domain> for STARTTLS enabled XMPP it supplies the XML stream to-'' domain -- sometimes needed --mx <domain/host> tests MX records from high to low priority (STARTTLS, port 25) --ip <ipv4> a) tests the supplied <ipv4> instead of resolving host(s) in URI b) arg "one" means: just test the first DNS returns (useful for multiple IPs) --file <file name> mass testing option: Just put multiple testssl.sh command lines in <file name>, one line per instance. Comments via # allowed, EOF signals end of <file name>. partly mandatory parameters: URI host|host:port|URL|URL:port (port 443 is assumed unless otherwise specified) pattern an ignore case word pattern of cipher hexcode or any other string in the name, kx or bits protocol is one of ftp,smtp,pop3,imap,xmpp,telnet,ldap (for the latter two you need e.g. the supplied openssl) tuning options: --assuming-http if protocol check fails it assumes HTTP protocol and enforces HTTP checks --ssl-native fallback to checks with OpenSSL where sockets are normally used --openssl <PATH> use this openssl binary (default: look in $PATH, $RUN_DIR of testssl.sh --proxy <host>:<port> connect via the specified HTTP proxy --sneaky be less verbose wrt referer headers --quiet don't output the banner. By doing this you acknowledge usage terms normally appearing in the banner --wide wide output for tests like RC4, BEAST. PFS also with hexcode, kx, strength, RFC name --show-each for wide outputs: display all ciphers tested -- not only succeeded ones --warnings <batch|off|false> "batch" doesn't wait for keypress, "off" or "false" skips connection warning --color <0|1|2> 0: no escape or other codes, 1: b/w escape codes, 2: color (default) --debug <0-6> 1: screen output normal but debug output in temp files. 2-6: see line ~105 All options requiring a value can also be called with '=' (e.g. testssl.sh -t=smtp --wide --openssl=/usr/bin/openssl <URI>. <URI> is always the last parameter. Need HTML output? Just pipe through "aha" (Ansi HTML Adapter: github.com/theZiz/aha) like "testssl.sh <options> <URI> | aha >output.html" userid@somehost:~ %
Web Front End for testssl.sh
- Clone the testssl.sh-webfrontend repository with its main dependency testssl.sh by invocation of
git clone https://github.com/TKCERT/testssl.sh-webfrontend.git.
- Install Python 3 (
apt-get install python3) and the Python module Flask by running
pip3 install flask.
- Install aha (
apt-get install aha)
- Configure SSLTestPortal.py, especially application.secret_key, in its configuration section and create the required paths (log, result/html and result/json in the default configuration).
- Run SSLTestPortal.py or deploy it as WSGI script.