gnutls-cli(1) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | EXIT STATUS | SEE ALSO | AUTHORS | COPYRIGHT | BUGS | NOTES | COLOPHON

gnutls-cli(1)                 User Commands                gnutls-cli(1)

NAME         top

       gnutls-cli - GnuTLS client

SYNOPSIS         top

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

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

DESCRIPTION         top

       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         top

       -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.

       --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.

       --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.

       -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         top

       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         top

       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         top

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

AUTHORS         top

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

COPYRIGHT         top

       Copyright (C) 2000-2020 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         top

       Please send bug reports to: bugs@gnutls.org

NOTES         top

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

COLOPHON         top

       This page is part of the GnuTLS (GnuTLS Transport Layer Security
       Library) project.  Information about the project can be found at
       ⟨http://www.gnutls.org/⟩.  If you have a bug report for this
       manual page, send it to bugs@gnutls.org.  This page was obtained
       from the tarball gnutls-3.7.2.tar.xz fetched from
       ⟨http://www.gnutls.org/download.html⟩ on 2021-08-27.  If you
       discover any rendering problems in this HTML version of the page,
       or you believe there is a better or more up-to-date source for
       the page, or you have corrections or improvements to the
       information in this COLOPHON (which is not part of the original
       manual page), send a mail to man-pages@man7.org

3.7.2                          29 May 2021                 gnutls-cli(1)

Pages that refer to this page: gnutls-cli-debug(1)gnutls-serv(1)ldap.conf(5)lloadd.conf(5)slapd.conf(5)slapd-config(5)