gnutls-cli(1)
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. 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 known certificate has changed. The
no-strict-tofu form will disable the option.
This option will perform authentication as with option --tofu;
however, while --tofu asks whether to trust a changed public
key, this option will fail in case of public key changes.
--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.
-e, --rehandshake
Establish a session and rehandshake.
Connect, establish a session and rehandshake immediately.
-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). 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.
-f, --fingerprint
Send the openpgp fingerprint, instead of the key.
--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.
--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.
--pgpkeyfile=file
PGP Key file to use.
--pgpkeyring=file
PGP Key ring file to use.
--pgpcertfile=file
PGP Public Key (certificate) file to use. This option must
appear in combination with the following options: pgpkeyfile.
--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.
--pgpsubkey=string
PGP subkey to use (hex or auto).
--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.
--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.
--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.
--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 advertize. 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.
--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 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.
-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
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 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.
70 (EX_SOFTWARE)
libopts had an internal operational error. Please report it to
autogen-users@lists.sourceforge.net. Thank you.
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) 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 option definitions.
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