List supported SSL TLS versions for a specific OpenSSL build

Question

I have  for example  OpenSSL version 1 0 0o on my Linux system  and I want to know which SSL TLS versions are supported with this build   Is there a shell command to accomplish this

User · Answer

It s clumsy  but you can get this from the usage messages for s client or s server  which are  ifed at compile time to match the supported protocol versions  Use something like   openssl s client -help 2 gt  amp 1   awk   -ssl 0-9  -tls 0-9   print  1       in older releases any unknown -option will work  in 1 1 0 must be exactly -help

User · Answer

When you run OPENSSL command using s client this is the output  See the Cipher  if the cipher NULL it means that version of TLS is not supported  TLSv1 SSLv3  Cipher is ECDHE-RSA-AES256 Server public key is 2048 bit Secure Renegotiation IS supported Compression  NONE Expansion  NONE No ALPN negotiated SSL-Session      Protocol    TLSv1     Cipher      ECDHE-RSA-AES256     Session-ID  A84600002D4945DE6     Session-ID-ctx      Master-Key        Start Time  15852343333860     Timeout     2343  sec      Verify return code  0  ok

User · Answer

You can not check for version support via command line  Best option would be checking OpenSSL changelog   Openssl versions till 1 0 0h supports SSLv2  SSLv3 and TLSv1 0  From Openssl 1 0 1 onward support for TLSv1 1 and TLSv1 2 is added

User · Answer

Try the following command   openssl ciphers   This should produce a list of all of the ciphers supported in your version of openssl   To see just a particular set of ciphers  e g  just sslv3 ciphers  try   openssl ciphers -ssl3   See https   www openssl org docs apps ciphers html for more info

User · Answer

This worked for me   openssl s client -help 2 gt  amp 1   gt   dev null   egrep   - ssl tls   a-z     Please let me know if this is wrong

User · Answer

Use this   openssl ciphers -v   awk   print  2     sort   uniq

[linux] List supported SSL/TLS versions for a specific OpenSSL build

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