A script to scan for TLS protocol and cipher support

This is a Bash script which uses OpenSSL to scan a remote host's SSL/TLS protocol and cipher support

• Output in JSON
• Shows preferred connection parameters
• Shows information about export level cipher suites
• Shows information about forward secrecy
• Shows Diffie-Hellman bit length
• Shows elliptic curve type/name

Compatibility

• Tested with OpenSSL 0.9.8 through 1.1.1q
• Scans for SSLv2 through TLSv1.3

Usage

./tlsscan.sh [ OPTIONS ] host
A program to scan for SSL/TLS protocols and cipher suites

Options:
  --ciphers LIST    An openssl cipher string for use with TLSv1.2 and lower.
                    Default: "@SECLEVEL=0:ALL:COMPLEMENTOFALL"
  --suites LIST     An openssl ciphersuite string for use with TLSv1.3.
                    Default: all available TLSv1.3 suites
  -h, --help        This message.
  -p, --port PORT   Which port to use. Defaults to 443. If 21, 25, 110, 143,
                    389, or 589 then --starttls is assumed.
  --pretty          Pretty print output.
  --progress        Display progress while scanning.
  --protocols LIST  A space seperated list of protocols. Defaults to detected
                    openssl s_client capability.
                    Example: --protocols "tls1 tls1_1"
  --proxy HOST:PORT Use a SOCKS proxy. Requires tsocks.
  --sni HOSTNAME    Use HOSTNAME as the Server Name Indicator value.
  --starttls PROTO  Use starttls for given PROTO, assumed with standard ports.
  -v, --version     Show version information.

Requirements

• jq
• OpenSSL
• tsocks (optional)

Note

Because this program is dependent on OpenSSL its results will vary with the version and capabilities of OpenSSL.