gnutls-cli-debug(1)



NAME

   gnutls-cli-debug - GnuTLS debug client

SYNOPSIS

   gnutls-cli-debug [-flags] [-flag [value]] [--option-name[[=| ]value]]

   Operands and options may be intermixed.  They will be reordered.

DESCRIPTION

   TLS  debug  client. It sets up multiple TLS connections to a server and
   queries its capabilities. It was created to assist in debugging GnuTLS,
   but  it  might  be  useful  to extract a TLS server's capabilities.  It
   connects to a  TLS  server,  performs  tests  and  print  the  server's
   capabilities.  If  called  with  the `-v' parameter more checks will be
   performed.  Can be used to check for  servers  with  special  needs  or
   bugs.

OPTIONS

   -d number, --debug=number
          Enable  debugging.   This  option takes an integer number as its
          argument.  The value of number is constrained to being:
              in the range  0 through 9999

          Specifies the debug level.

   -V, --verbose
          More verbose output.  This option may appear an unlimited number
          of times.

   -p number, --port=number
          The port to connect to.  This option takes an integer number as
          its argument.  The value of number is constrained to being:
              in the range  0 through 65536

   --app-proto
          This is an alias for the --starttls-proto option.

   --starttls-proto=string
          The application protocol to be used to obtain the server's
          certificate (https, ftp, smtp, imap, ldap, xmpp).

          Specify the application layer protocol for STARTTLS. If the
          protocol is supported, gnutls-cli will proceed to the TLS
          negotiation.

   -h, --help
          Display usage information and exit.

   -!, --more-help
          Pass the extended usage information through a pager.

   -v [{v|c|n --version [{v|c|n}]}]
          Output version of program and exit.  The default mode is `v', a
          simple version.  The `c' mode will print copyright information
          and `n' will print the full copyright notice.

EXAMPLES

       $ gnutls-cli-debug localhost
       GnuTLS debug client 3.5.0
       Checking localhost:443
                                    for SSL 3.0 (RFC6101) support... yes
                               whether we need to disable TLS 1.2... no
                               whether we need to disable TLS 1.1... no
                               whether we need to disable TLS 1.0... no
                               whether %NO_EXTENSIONS is required... no
                                      whether %COMPAT is required... no
                                    for TLS 1.0 (RFC2246) support... yes
                                    for TLS 1.1 (RFC4346) support... yes
                                    for TLS 1.2 (RFC5246) support... yes
                                         fallback from TLS 1.6 to... TLS1.2
                               for RFC7507 inappropriate fallback... yes
                                            for HTTPS server name... Local
                                      for certificate chain order... sorted
                         for safe renegotiation (RFC5746) support... yes
                            for Safe renegotiation support (SCSV)... no
                           for encrypt-then-MAC (RFC7366) support... no
                          for ext master secret (RFC7627) support... no
                                  for heartbeat (RFC6520) support... no
                              for version rollback bug in RSA PMS... dunno
                         for version rollback bug in Client Hello... no
                   whether the server ignores the RSA PMS version... yes
       whether small records (512 bytes) are tolerated on handshake... yes
           whether cipher suites not in SSL 3.0 spec are accepted... yes
       whether a bogus TLS record version in the client hello is accepted... yes
                whether the server understands TLS closure alerts... partially
                   whether the server supports session resumption... yes
                             for anonymous authentication support... no
                             for ephemeral Diffie-Hellman support... no
                          for ephemeral EC Diffie-Hellman support... yes
                           ephemeral EC Diffie-Hellman group info... SECP256R1
                         for AES-128-GCM cipher (RFC5288) support... yes
                         for AES-128-CCM cipher (RFC6655) support... no
                       for AES-128-CCM-8 cipher (RFC6655) support... no
                         for AES-128-CBC cipher (RFC3268) support... yes
                    for CAMELLIA-128-GCM cipher (RFC6367) support... no
                    for CAMELLIA-128-CBC cipher (RFC5932) support... no
                            for 3DES-CBC cipher (RFC2246) support... yes
                         for ARCFOUR 128 cipher (RFC2246) support... yes
                                              for MD5 MAC support... yes
                                             for SHA1 MAC support... yes
                                           for SHA256 MAC support... yes
                                     for ZLIB compression support... no
                            for max record size (RFC6066) support... no
                       for OCSP status response (RFC6066) support... no
                     for OpenPGP authentication (RFC6091) support... no

   You could also use the client to debug services with starttls
   capability.
       $ gnutls-cli-debug --starttls-proto smtp --port 25 localhost

EXIT STATUS

   One of the following exit values will be returned:

   0  (EXIT_SUCCESS)
          Successful program execution.

   1  (EXIT_FAILURE)
          The operation failed or the command syntax was not valid.

   70  (EX_SOFTWARE)
          libopts had an internal operational error.  Please report it to
          autogen-users@lists.sourceforge.net.  Thank you.

SEE ALSO

   gnutls-cli(1), gnutls-serv(1)

AUTHORS

   Nikos Mavrogiannopoulos, Simon Josefsson and others; see
   /usr/share/doc/gnutls/AUTHORS for a complete list.

COPYRIGHT

   Copyright (C) 2000-2016 Free Software Foundation, and others all rights
   reserved.  This program is released under the terms of the GNU General
   Public License, version 3 or later.

BUGS

   Please send bug reports to: bugs@gnutls.org

NOTES

   This manual page was AutoGen-erated from the gnutls-cli-debug option
   definitions.




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