gnutls-serv(1)
NAME
gnutls-serv - GnuTLS server
SYNOPSIS
gnutls-serv [-flags] [-flag [value]] [--option-name[[=| ]value]] All arguments must be options.
DESCRIPTION
Server program that listens to incoming TLS connections.
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.
--sni-hostname=string
Server's hostname for server name extension.
Server name of type host_name that the server will recognise as
its own. If the server receives client hello with different
name, it will send a warning-level unrecognized_name alert.
--sni-hostname-fatal
Send fatal alert on sni-hostname mismatch.
--noticket
Don't accept session tickets.
-g, --generate
Generate Diffie-Hellman parameters.
-q, --quiet
Suppress some messages.
--nodb Do not use a resumption database.
--http Act as an HTTP server.
--echo Act as an Echo server.
-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
--srtp-profiles=string
Offer SRTP profiles.
-a, --disable-client-cert
Do not request a client certificate.
-r, --require-client-cert
Require a client certificate.
--verify-client-cert
If a client certificate is sent then verify it..
Do not require, but if a client certificate is sent then verify
it and close the connection if invalid.
-b, --heartbeat
Activate heartbeat support.
Regularly ping client via heartbeat extension messages
--x509fmtder
Use DER format for certificates to read from.
--priority=string
Priorities string.
TLS algorithms and protocols to enable. You can use predefined
sets of ciphersuites such as PERFORMANCE, NORMAL, SECURE128,
SECURE256. The default is NORMAL.
Check the GnuTLS manual on section "Priority strings" for
more information on allowed keywords
--dhparams=file
DH params file to use.
--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.
--x509keyfile=string
X.509 key file or PKCS #11 URL to use.
--x509certfile=string
X.509 Certificate file or PKCS #11 URL to use.
--x509dsakeyfile=string
Alternative X.509 key file or PKCS #11 URL to use.
--x509dsacertfile=string
Alternative X.509 Certificate file or PKCS #11 URL to use.
--x509ecckeyfile=string
Alternative X.509 key file or PKCS #11 URL to use.
--x509ecccertfile=string
Alternative X.509 Certificate file or PKCS #11 URL to use.
--pgpsubkey=string
PGP subkey to use (hex or auto).
--srppasswd=file
SRP password file to use.
--srppasswdconf=file
SRP password configuration file to use.
--pskpasswd=file
PSK password file to use.
--pskhint=string
PSK identity hint to use.
--ocsp-response=file
The OCSP response to send to client.
If the client requested an OCSP response, return data from this
file to the client.
-p number, --port=number
The port to connect to. This option takes an integer number as
its argument.
-l, --list
Print a list of the supported algorithms and modes.
Print a list of the supported algorithms and modes. If a
priority string is given then only the enabled ciphersuites are
shown.
--provider=file
Specify the PKCS #11 provider library.
This will override the default options in
/etc/gnutls/pkcs11.conf
-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
Running your own TLS server based on GnuTLS can be useful when
debugging clients and/or GnuTLS itself. This section describes how to
use gnutls-serv as a simple HTTPS server.
The most basic server can be started as:
gnutls-serv --http --priority "NORMAL:+ANON-ECDH:+ANON-DH"
It will only support anonymous ciphersuites, which many TLS clients
refuse to use.
The next step is to add support for X.509. First we generate a CA:
$ certtool --generate-privkey > x509-ca-key.pem
$ echo 'cn = GnuTLS test CA' > ca.tmpl
$ echo 'ca' >> ca.tmpl
$ echo 'cert_signing_key' >> ca.tmpl
$ certtool --generate-self-signed --load-privkey x509-ca-key.pem --template ca.tmpl --outfile x509-ca.pem
Then generate a server certificate. Remember to change the dns_name
value to the name of your server host, or skip that command to avoid
the field.
$ certtool --generate-privkey > x509-server-key.pem
$ echo 'organization = GnuTLS test server' > server.tmpl
$ echo 'cn = test.gnutls.org' >> server.tmpl
$ echo 'tls_www_server' >> server.tmpl
$ echo 'encryption_key' >> server.tmpl
$ echo 'signing_key' >> server.tmpl
$ echo 'dns_name = test.gnutls.org' >> server.tmpl
$ certtool --generate-certificate --load-privkey x509-server-key.pem --load-ca-certificate x509-ca.pem --load-ca-privkey x509-ca-key.pem --template server.tmpl --outfile x509-server.pem
For use in the client, you may want to generate a client certificate as
well.
$ certtool --generate-privkey > x509-client-key.pem
$ echo 'cn = GnuTLS test client' > client.tmpl
$ echo 'tls_www_client' >> client.tmpl
$ echo 'encryption_key' >> client.tmpl
$ echo 'signing_key' >> client.tmpl
$ certtool --generate-certificate --load-privkey x509-client-key.pem --load-ca-certificate x509-ca.pem --load-ca-privkey x509-ca-key.pem --template client.tmpl --outfile x509-client.pem
To be able to import the client key/certificate into some applications,
you will need to convert them into a PKCS#12 structure. This also
encrypts the security sensitive key with a password.
$ certtool --to-p12 --load-ca-certificate x509-ca.pem --load-privkey x509-client-key.pem --load-certificate x509-client.pem --outder --outfile x509-client.p12
For icing, we'll create a proxy certificate for the client too.
$ certtool --generate-privkey > x509-proxy-key.pem
$ echo 'cn = GnuTLS test client proxy' > proxy.tmpl
$ certtool --generate-proxy --load-privkey x509-proxy-key.pem --load-ca-certificate x509-client.pem --load-ca-privkey x509-client-key.pem --load-certificate x509-client.pem --template proxy.tmpl --outfile x509-proxy.pem
Then start the server again:
$ gnutls-serv --http --x509cafile x509-ca.pem --x509keyfile x509-server-key.pem --x509certfile x509-server.pem
Try connecting to the server using your web browser. Note that the
server listens to port 5556 by default.
While you are at it, to allow connections using DSA, you can also
create a DSA key and certificate for the server. These credentials
will be used in the final example below.
$ certtool --generate-privkey --dsa > x509-server-key-dsa.pem
$ certtool --generate-certificate --load-privkey x509-server-key-dsa.pem --load-ca-certificate x509-ca.pem --load-ca-privkey x509-ca-key.pem --template server.tmpl --outfile x509-server-dsa.pem
The next step is to create OpenPGP credentials for the server.
gpg --gen-key
Enter whatever details you want, use 'test.gnutls.org' as name...
Make a note of the OpenPGP key identifier of the newly generated key,
here it was 5D1D14D8. You will need to export the key for GnuTLS to be
able to use it.
gpg -a --export 5D1D14D8 > openpgp-server.txt
gpg --export 5D1D14D8 > openpgp-server.bin
gpg --export-secret-keys 5D1D14D8 > openpgp-server-key.bin
gpg -a --export-secret-keys 5D1D14D8 > openpgp-server-key.txt
Let's start the server with support for OpenPGP credentials:
gnutls-serv --http --priority NORMAL:+CTYPE-OPENPGP --pgpkeyfile openpgp-server-key.txt --pgpcertfile openpgp-server.txt
The next step is to add support for SRP authentication. This requires
an SRP password file created with srptool. To start the server with
SRP support:
gnutls-serv --http --priority NORMAL:+SRP-RSA:+SRP --srppasswdconf srp-tpasswd.conf --srppasswd srp-passwd.txt
Let's also start a server with support for PSK. This would require a
password file created with psktool.
gnutls-serv --http --priority NORMAL:+ECDHE-PSK:+PSK --pskpasswd psk-passwd.txt
Finally, we start the server with all the earlier parameters and you
get this command:
gnutls-serv --http --priority NORMAL:+PSK:+SRP:+CTYPE-OPENPGP --x509cafile x509-ca.pem --x509keyfile x509-server-key.pem --x509certfile x509-server.pem --x509dsakeyfile x509-server-key-dsa.pem --x509dsacertfile x509-server-dsa.pem --pgpkeyfile openpgp-server-key.txt --pgpcertfile openpgp-server.txt --srppasswdconf srp-tpasswd.conf --srppasswd srp-passwd.txt --pskpasswd psk-passwd.txt
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
[email protected]. Thank you.
SEE ALSO
gnutls-cli-debug(1), gnutls-cli(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: [email protected]
NOTES
This manual page was AutoGen-erated from the gnutls-serv option definitions.
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