Provided by: gnutls-bin_3.7.3-4ubuntu1.5_amd64 bug

NAME

       gnutls-cli - GnuTLS client

SYNOPSIS

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

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

DESCRIPTION

       Simple client program to set up a TLS connection to some other computer.  It sets up a TLS
       connection and forwards data from the standard input to the secured socket and vice versa.

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.

       --tofu, --no-tofu
              Enable trust on first use authentication.  The no-tofu form will disable the
              option.

              This option will, in addition to certificate authentication, perform authentication
              based on previously seen public keys, a model similar to SSH authentication. Note
              that when tofu is specified (PKI) and DANE authentication will become advisory to
              assist the public key acceptance process.

       --strict-tofu, --no-strict-tofu
              Fail to connect if a certificate is unknown or a known certificate has changed.
              The no-strict-tofu form will disable the option.

              This option will perform authentication as with option --tofu; however, no
              questions shall be asked whatsoever, neither to accept an unknown certificate nor a
              changed one.

       --dane, --no-dane
              Enable DANE certificate verification (DNSSEC).  The no-dane form will disable the
              option.

              This option will, in addition to certificate authentication using the trusted CAs,
              verify the server certificates using on the DANE information available via DNSSEC.

       --local-dns, --no-local-dns
              Use the local DNS server for DNSSEC resolving.  The no-local-dns form will disable
              the option.

              This option will use the local DNS server for DNSSEC.  This is disabled by default
              due to many servers not allowing DNSSEC.

       --ca-verification, --no-ca-verification
              Enable CA certificate verification.  The no-ca-verification form will disable the
              option.  This option is enabled by default.

              This option can be used to enable or disable CA certificate verification. It is to
              be used with the --dane or --tofu options.

       --ocsp, --no-ocsp
              Enable OCSP certificate verification.  The no-ocsp form will disable the option.

              This option will enable verification of the peer's certificate using ocsp

       -r, --resume
              Establish a session and resume.

              Connect, establish a session, reconnect and resume.

       --earlydata=string
              Send early data on resumption from the specified file.

       -e, --rehandshake
              Establish a session and rehandshake.

              Connect, establish a session and rehandshake immediately.

       --sni-hostname=string
              Server's hostname for server name indication extension.

              Set explicitly the server name used in the TLS server name indication extension.
              That is useful when testing with servers setup on different DNS name than the
              intended. If not specified, the provided hostname is used. Even with this option
              server certificate verification still uses the hostname passed on the main
              commandline. Use --verify-hostname to change this.

       --verify-hostname=string
              Server's hostname to use for validation.

              Set explicitly the server name to be used when validating the server's certificate.

       -s, --starttls
              Connect, establish a plain session and start TLS.

              The TLS session will be initiated when EOF or a SIGALRM is received.

       --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, lmtp, pop3, nntp, sieve, postgres).  This option must not
              appear in combination with any of the following options: starttls.

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

       -u, --udp
              Use DTLS (datagram TLS) over UDP.

       --mtu=number
              Set MTU for datagram TLS.  This option takes an integer number as its argument.
              The value of number is constrained to being:
                  in the range 0 through 17000

       --crlf Send CR LF instead of LF.

       --fastopen
              Enable TCP Fast Open.

       --x509fmtder
              Use DER format for certificates to read from.

       --print-cert
              Print peer's certificate in PEM format.

       --save-cert=string
              Save the peer's certificate chain in the specified file in PEM format.

       --save-ocsp=string
              Save the peer's OCSP status response in the provided file.  This option must not
              appear in combination with any of the following options: save-ocsp-multi.

       --save-ocsp-multi=string
              Save all OCSP responses provided by the peer in this file.  This option must not
              appear in combination with any of the following options: save-ocsp.

              The file will contain a list of PEM encoded OCSP status responses if any were
              provided by the peer, starting with the one for the peer's server certificate.

       --save-server-trace=string
              Save the server-side TLS message trace in the provided file.

       --save-client-trace=string
              Save the client-side TLS message trace in the provided file.

       --dh-bits=number
              The minimum number of bits allowed for DH.  This option takes an integer number as
              its argument.

              This option sets the minimum number of bits allowed for a Diffie-Hellman key
              exchange. You may want to lower the default value if the peer sends a weak prime
              and you get an connection error with unacceptable prime.

       --priority=string
              Priorities string.

              TLS algorithms and protocols to enable. You can use predefined sets of ciphersuites
              such as PERFORMANCE, NORMAL, PFS, SECURE128, SECURE256. The default is NORMAL.

              Check  the  GnuTLS  manual  on  section  “Priority strings” for more information on
              the allowed keywords

       --x509cafile=string
              Certificate file or PKCS #11 URL to use.

       --x509crlfile=file
              CRL file to use.

       --x509keyfile=string
              X.509 key file or PKCS #11 URL to use.

       --x509certfile=string
              X.509 Certificate file or PKCS #11 URL to use.  This option must appear in
              combination with the following options: x509keyfile.

       --rawpkkeyfile=string
              Private key file (PKCS #8 or PKCS #12) or PKCS #11 URL to use.

              In order to instruct the application to negotiate raw public keys one must enable
              the respective certificate types via the priority strings (i.e. CTYPE-CLI-* and
              CTYPE-SRV-* flags).

              Check  the  GnuTLS  manual  on  section  “Priority strings” for more information on
              how to set certificate types.

       --rawpkfile=string
              Raw public-key file to use.  This option must appear in combination with the
              following options: rawpkkeyfile.

              In order to instruct the application to negotiate raw public keys one must enable
              the respective certificate types via the priority strings (i.e. CTYPE-CLI-* and
              CTYPE-SRV-* flags).

              Check  the  GnuTLS  manual  on  section  “Priority strings” for more information on
              how to set certificate types.

       --srpusername=string
              SRP username to use.

       --srppasswd=string
              SRP password to use.

       --pskusername=string
              PSK username to use.

       --pskkey=string
              PSK key (in hex) to use.

       -p string, --port=string
              The port or service to connect to.

       --insecure
              Don't abort program if server certificate can't be validated.

       --verify-allow-broken
              Allow broken algorithms, such as MD5 for certificate verification.

       --ranges
              Use length-hiding padding to prevent traffic analysis.

              When possible (e.g., when using CBC ciphersuites), use length-hiding padding to
              prevent traffic analysis.

              NOTE: THIS OPTION IS DEPRECATED

       --benchmark-ciphers
              Benchmark individual ciphers.

              By default the benchmarked ciphers will utilize any capabilities of the local CPU
              to improve performance. To test against the raw software implementation set the
              environment variable GNUTLS_CPUID_OVERRIDE to 0x1.

       --benchmark-tls-kx
              Benchmark TLS key exchange methods.

       --benchmark-tls-ciphers
              Benchmark TLS ciphers.

              By default the benchmarked ciphers will utilize any capabilities of the local CPU
              to improve performance. To test against the raw software implementation set the
              environment variable GNUTLS_CPUID_OVERRIDE to 0x1.

       -l, --list
              Print a list of the supported algorithms and modes.  This option must not appear in
              combination with any of the following options: port.

              Print a list of the supported algorithms and modes. If a priority string is given
              then only the enabled ciphersuites are shown.

       --priority-list
              Print a list of the supported priority strings.

              Print a list of the supported priority strings. The ciphersuites corresponding to
              each priority string can be examined using -l -p.

       --noticket
              Don't allow session tickets.

              Disable the request of receiving of session tickets under TLS1.2 or earlier

       --srtp-profiles=string
              Offer SRTP profiles.

       --alpn=string
              Application layer protocol.  This option may appear an unlimited number of times.

              This option will set and enable the Application Layer Protocol Negotiation  (ALPN)
              in the TLS protocol.

       -b, --heartbeat
              Activate heartbeat support.

       --recordsize=number
              The maximum record size to advertise.  This option takes an integer number as its
              argument.  The value of number is constrained to being:
                  in the range 0 through 4096

       --disable-sni
              Do not send a Server Name Indication (SNI).

       --disable-extensions
              Disable all the TLS extensions.

              This option disables all TLS extensions. Deprecated option. Use the priority
              string.

              NOTE: THIS OPTION IS DEPRECATED

       --single-key-share
              Send a single key share under TLS1.3.

              This option switches the default mode of sending multiple key shares, to send a
              single one (the top one).

       --post-handshake-auth
              Enable post-handshake authentication under TLS1.3.

              This option enables post-handshake authentication when under TLS1.3.

       --inline-commands
              Inline commands of the form ^<cmd>^.

              Enable inline commands of the form ^<cmd>^. The inline commands are expected to be
              in a line by themselves. The available commands are: resume, rekey1 (local rekey),
              rekey (rekey on both peers) and renegotiate.

       --inline-commands-prefix=string
              Change the default delimiter for inline commands..

              Change the default delimiter (^) used for inline commands. The delimiter is
              expected to be a single US-ASCII character (octets 0 - 127). This option is only
              relevant if inline commands are enabled via the inline-commands option

       --provider=file
              Specify the PKCS #11 provider library.

              This will override the default options in /etc/gnutls/pkcs11.conf

       --fips140-mode
              Reports the status of the FIPS140-2 mode in gnutls library.

       --list-config
              Reports the configuration of the library.

       --logfile=string
              Redirect informational messages to a specific file..

              Redirect informational messages to a specific file. The file may be /dev/null also
              to make the gnutls client quiet to use it in piped server connections where only
              the server communication may appear on stdout.

       --keymatexport=string
              Label used for exporting keying material.

       --keymatexportsize=number
              Size of the exported keying material.  This option takes an integer number as its
              argument.

       --waitresumption
              Block waiting for the resumption data under TLS1.3.

              This option makes the client to block waiting for the resumption data under TLS1.3.
              The option has effect only when --resume is provided.

       --ca-auto-retrieve, --no-ca-auto-retrieve
              Enable automatic retrieval of missing CA certificates.  The no-ca-auto-retrieve
              form will disable the option.

              This option enables the client to automatically retrieve the missing intermediate
              CA certificates in the certificate chain, based on the Authority Information Access
              (AIA) extension.

       -v keyword, --version=keyword
              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.

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

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

EXAMPLES

       Connecting using PSK authentication
       To connect to a server using PSK authentication, you need to enable the choice of PSK by
       using a cipher priority parameter such as in the example below.
           $ ./gnutls-cli -p 5556 localhost --pskusername psk_identity     --pskkey 88f3824b3e5659f52d00e959bacab954b6540344     --priority NORMAL:-KX-ALL:+ECDHE-PSK:+DHE-PSK:+PSK
           Resolving 'localhost'...
           Connecting to '127.0.0.1:5556'...
           - PSK authentication.
           - Version: TLS1.1
           - Key Exchange: PSK
           - Cipher: AES-128-CBC
           - MAC: SHA1
           - Compression: NULL
           - Handshake was completed

           - Simple Client Mode:
       By keeping the --pskusername parameter and removing the --pskkey parameter, it will query
       only for the password during the handshake.

       Connecting using raw public-key authentication
       To connect to a server using raw public-key authentication, you need to enable the option
       to negotiate raw public-keys via the priority strings such as in the example below.
           $ ./gnutls-cli -p 5556 localhost --priority NORMAL:-CTYPE-CLI-ALL:+CTYPE-CLI-RAWPK     --rawpkkeyfile cli.key.pem     --rawpkfile cli.rawpk.pem
           Processed 1 client raw public key pair...
           Resolving 'localhost'...
           Connecting to '127.0.0.1:5556'...
           - Successfully sent 1 certificate(s) to server.
           - Server has requested a certificate.
           - Certificate type: X.509
           - Got a certificate list of 1 certificates.
           - Certificate[0] info:
            - skipped
           - Description: (TLS1.3-Raw Public Key-X.509)-(ECDHE-SECP256R1)-(RSA-PSS-RSAE-SHA256)-(AES-256-GCM)
           - Options:
           - Handshake was completed

           - Simple Client Mode:

       Connecting to STARTTLS services

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

       Listing ciphersuites in a priority string
       To list the ciphersuites in a priority string:
           $ ./gnutls-cli --priority SECURE192 -l
           Cipher suites for SECURE192
           TLS_ECDHE_ECDSA_AES_256_CBC_SHA384         0xc0, 0x24  TLS1.2
           TLS_ECDHE_ECDSA_AES_256_GCM_SHA384         0xc0, 0x2e  TLS1.2
           TLS_ECDHE_RSA_AES_256_GCM_SHA384           0xc0, 0x30  TLS1.2
           TLS_DHE_RSA_AES_256_CBC_SHA256             0x00, 0x6b  TLS1.2
           TLS_DHE_DSS_AES_256_CBC_SHA256             0x00, 0x6a  TLS1.2
           TLS_RSA_AES_256_CBC_SHA256                 0x00, 0x3d  TLS1.2

           Certificate types: CTYPE-X.509
           Protocols: VERS-TLS1.2, VERS-TLS1.1, VERS-TLS1.0, VERS-SSL3.0, VERS-DTLS1.0
           Compression: COMP-NULL
           Elliptic curves: CURVE-SECP384R1, CURVE-SECP521R1
           PK-signatures: SIGN-RSA-SHA384, SIGN-ECDSA-SHA384, SIGN-RSA-SHA512, SIGN-ECDSA-SHA512

       Connecting using a PKCS #11 token
       To connect to a server using a certificate and a private key present in a PKCS #11 token
       you need to substitute the PKCS 11 URLs in the x509certfile and x509keyfile parameters.

       Those can be found using "p11tool --list-tokens" and then listing all the objects in the
       needed token, and using the appropriate.
           $ p11tool --list-tokens

           Token 0:
                URL: pkcs11:model=PKCS15;manufacturer=MyMan;serial=1234;token=Test
                Label: Test
                Manufacturer: EnterSafe
                Model: PKCS15
                Serial: 1234

           $ p11tool --login --list-certs "pkcs11:model=PKCS15;manufacturer=MyMan;serial=1234;token=Test"

           Object 0:
                URL: pkcs11:model=PKCS15;manufacturer=MyMan;serial=1234;token=Test;object=client;type=cert
                Type: X.509 Certificate
                Label: client
                ID: 2a:97:0d:58:d1:51:3c:23:07:ae:4e:0d:72:26:03:7d:99:06:02:6a

           $ MYCERT="pkcs11:model=PKCS15;manufacturer=MyMan;serial=1234;token=Test;object=client;type=cert"
           $ MYKEY="pkcs11:model=PKCS15;manufacturer=MyMan;serial=1234;token=Test;object=client;type=private"
           $ export MYCERT MYKEY

           $ gnutls-cli www.example.com --x509keyfile $MYKEY --x509certfile $MYCERT
       Notice that the private key only differs from the certificate in the type.

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.

SEE ALSO

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

AUTHORS

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

COPYRIGHT

       Copyright (C) 2020-2021 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