Openssl s_client命令

openssl s_client [-host host] [-port port] [-connect host:port] [-verify depth] [-cert filename] [-certform DER|PEM] [-key filename] [-keyform DER|PEM] [-pass arg] [-CApath directory] [-CAfile filename] [-reconnect][-pause] [-showcerts] [-debug] [-msg] [-state] [-nbio_test] [-nbio][-crlf] [-ign_eof] [-no_ign_eof] [-quiet] [-ssl2] [-ssl3] [-tls1_1] [-tls1_2] [-tls1] [-dtls1] [-no_ssl2][-no_ssl3] [-no_tls1] [-no_tls1_1] [-no_tls1_2] [-bugs] [-cipher cipherlist] [-starttls protocol] [-engine id] [-tlsextdebug] [-no_ticket] [-sess_out filename] [-sess_in filename] [-rand file(s)]

-host host     - use -connect instead
 -port port     - use -connect instead
 -connect host:port - who to connect to (default is localhost:4433)
 -verify arg   - turn on peer certificate verification
 -cert arg     - certificate file to use, PEM format assumed
 -certform arg - certificate format (PEM or DER) PEM default
 -key arg      - Private key file to use, in cert file if
                 not specified but cert file is.
 -keyform arg  - key format (PEM or DER) PEM default
 -pass arg     - private key file pass phrase source
 -CApath arg   - PEM format directory of CA‘s
 -CAfile arg   - PEM format file of CA‘s
 -trusted_first - Use trusted CA‘s first when building the trust chain
 -reconnect    - Drop and re-make the connection with the same Session-ID
 -pause        - sleep(1) after each read(2) and write(2) system call
 -showcerts    - show all certificates in the chain
 -debug        - extra output
 -msg          - Show protocol messages
 -nbio_test    - more ssl protocol testing
 -state        - print the ‘ssl‘ states
 -nbio         - Run with non-blocking IO
 -crlf         - convert LF from terminal into CRLF
 -quiet        - no s_client output
 -ign_eof      - ignore input eof (default when -quiet)
 -no_ign_eof   - don‘t ignore input eof
 -psk_identity arg - PSK identity
 -psk arg      - PSK in hex (without 0x)
 -ssl2         - just use SSLv2
 -ssl3         - just use SSLv3
 -tls1_2       - just use TLSv1.2
 -tls1_1       - just use TLSv1.1
 -tls1         - just use TLSv1
 -dtls1        - just use DTLSv1
 -mtu          - set the link layer MTU
 -no_tls1_2/-no_tls1_1/-no_tls1/-no_ssl3/-no_ssl2 - turn off that protocol
 -bugs         - Switch on all SSL implementation bug workarounds
 -serverpref   - Use server‘s cipher preferences (only SSLv2)
 -cipher       - preferred cipher to use, use the ‘openssl ciphers‘
                 command to see what is available
 -starttls prot - use the STARTTLS command before starting TLS
                 for those protocols that support it, where
                 ‘prot‘ defines which one to assume.  Currently,
                 only "smtp", "pop3", "imap", "ftp" and "xmpp"
                 are supported.
 -engine id    - Initialise and use the specified engine
 -rand file:file:...
 -sess_out arg - file to write SSL session to
 -sess_in arg  - file to read SSL session from
 -servername host  - Set TLS extension servername in ClientHello
 -tlsextdebug      - hex dump of all TLS extensions received
 -status           - request certificate status from server
 -no_ticket        - disable use of RFC4507bis session tickets
 -nextprotoneg arg - enable NPN extension, considering named protocols supported (comma-separated list)
 -legacy_renegotiation - enable use of legacy renegotiation (dangerous)
 -use_srtp profiles - Offer SRTP key management with a colon-separated profile list
 -keymatexport label   - Export keying material using label
 -keymatexportlen len  - Export len bytes of keying material (default 20)

参考：http://blog.csdn.net/as3luyuan123/article/details/16812071