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|
AutoGen Definitions options;
prog-name = gnutls-serv;
prog-title = "GnuTLS server";
prog-desc = "Simple server program to act as an HTTPS or TLS echo service.";
short-usage = "Usage: gnutls-serv [options]\ngnutls-serv --help for usage instructions.\n";
explain = "";
detail = "Server program that listens to incoming TLS connections.";
#include args-std.def
flag = {
name = sni-hostname;
descrip = "Server's hostname for server name extension";
arg-type = string;
doc = "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.";
};
flag = {
name = sni-hostname-fatal;
descrip = "Send fatal alert on sni-hostname mismatch";
doc = "";
};
flag = {
name = noticket;
descrip = "Don't accept session tickets";
doc = "";
};
flag = {
name = generate;
value = g;
descrip = "Generate Diffie-Hellman parameters";
doc = "";
};
flag = {
name = quiet;
value = q;
descrip = "Suppress some messages";
doc = "";
};
flag = {
name = nodb;
descrip = "Do not use a resumption database";
doc = "";
};
flag = {
name = http;
descrip = "Act as an HTTP server";
doc = "";
};
flag = {
name = echo;
descrip = "Act as an Echo server";
doc = "";
};
flag = {
name = udp;
value = u;
descrip = "Use DTLS (datagram TLS) over UDP";
doc = "";
};
flag = {
name = mtu;
arg-type = number;
arg-range = "0->17000";
descrip = "Set MTU for datagram TLS";
doc = "";
};
flag = {
name = srtp_profiles;
arg-type = string;
descrip = "Offer SRTP profiles";
doc = "";
};
flag = {
name = disable-client-cert;
value = a;
descrip = "Do not request a client certificate";
doc = "";
};
flag = {
name = require-client-cert;
value = r;
descrip = "Require a client certificate";
doc = "";
};
flag = {
name = verify-client-cert;
disabled;
descrip = "If a client certificate is sent then verify it.";
doc = "Do not require, but if a client certificate is sent then verify it and close the connection if invalid.";
};
flag = {
name = heartbeat;
value = b;
descrip = "Activate heartbeat support";
doc = "Regularly ping client via heartbeat extension messages";
};
flag = {
name = x509fmtder;
descrip = "Use DER format for certificates to read from";
doc = "";
};
flag = {
name = priority;
arg-type = string;
descrip = "Priorities string";
doc = "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";
};
flag = {
name = dhparams;
arg-type = file;
file-exists = yes;
descrip = "DH params file to use";
doc = "";
};
flag = {
name = x509cafile;
arg-type = string;
descrip = "Certificate file or PKCS #11 URL to use";
doc = "";
};
flag = {
name = x509crlfile;
arg-type = file;
file-exists = yes;
descrip = "CRL file to use";
doc = "";
};
flag = {
name = pgpkeyfile;
arg-type = file;
file-exists = yes;
descrip = "PGP Key file to use";
doc = "";
deprecated;
};
flag = {
name = x509keyfile;
arg-type = string;
descrip = "X.509 key file or PKCS #11 URL to use";
doc = "Specify the private key file or URI to use; it must correspond to
the certificate specified in --x509certfile. Multiple keys and certificates
can be specified with this option and in that case each occurence of keyfile
must be followed by the corresponding x509certfile or vice-versa.";
stack-arg;
max = NOLIMIT;
};
flag = {
name = x509certfile;
arg-type = string;
descrip = "X.509 Certificate file or PKCS #11 URL to use";
doc = "Specify the certificate file or URI to use; it must correspond to
the key specified in --x509keyfile. Multiple keys and certificates
can be specified with this option and in that case each occurence of keyfile
must be followed by the corresponding x509certfile or vice-versa.";
stack-arg;
max = NOLIMIT;
};
flag = {
name = x509dsakeyfile;
aliases = x509keyfile;
descrip = "Alternative X.509 key file or PKCS #11 URL to use";
deprecated;
};
flag = {
name = x509dsacertfile;
aliases = x509certfile;
descrip = "Alternative X.509 Certificate file or PKCS #11 URL to use";
deprecated;
};
flag = {
name = x509ecckeyfile;
aliases = x509keyfile;
descrip = "Alternative X.509 key file or PKCS #11 URL to use";
deprecated;
};
flag = {
name = x509ecccertfile;
aliases = x509certfile;
descrip = "Alternative X.509 Certificate file or PKCS #11 URL to use";
deprecated;
};
flag = {
name = srppasswd;
arg-type = file;
file-exists = yes;
descrip = "SRP password file to use";
doc = "";
};
flag = {
name = srppasswdconf;
arg-type = file;
file-exists = yes;
descrip = "SRP password configuration file to use";
doc = "";
};
flag = {
name = pskpasswd;
arg-type = file;
file-exists = yes;
descrip = "PSK password file to use";
doc = "";
};
flag = {
name = pskhint;
arg-type = string;
descrip = "PSK identity hint to use";
doc = "";
};
flag = {
name = ocsp-response;
arg-type = file;
file-exists = yes;
descrip = "The OCSP response to send to client";
doc = "If the client requested an OCSP response, return data from this file to the client.";
};
flag = {
name = port;
value = p;
arg-type = number;
descrip = "The port to connect to";
doc = "";
};
flag = {
name = list;
value = l;
descrip = "Print a list of the supported algorithms and modes";
doc = "Print a list of the supported algorithms and modes. If a priority string is given then only the enabled ciphersuites are shown.";
};
flag = {
name = provider;
arg-type = file;
file-exists = yes;
descrip = "Specify the PKCS #11 provider library";
doc = "This will override the default options in /etc/gnutls/pkcs11.conf";
};
doc-section = {
ds-type = 'SEE ALSO'; // or anything else
ds-format = 'texi'; // or texi or mdoc format
ds-text = <<-_EOText_
gnutls-cli-debug(1), gnutls-cli(1)
_EOText_;
};
doc-section = {
ds-type = 'EXAMPLES';
ds-format = 'texi';
ds-text = <<-_EOF_
Running your own TLS server based on GnuTLS can be useful when
debugging clients and/or GnuTLS itself. This section describes how to
use @code{gnutls-serv} as a simple HTTPS server.
The most basic server can be started as:
@example
gnutls-serv --http --priority "NORMAL:+ANON-ECDH:+ANON-DH"
@end example
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:
@example
$ 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
@end example
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.
@example
$ 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
@end example
For use in the client, you may want to generate a client certificate
as well.
@example
$ 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
@end example
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.
@example
$ 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
@end example
For icing, we'll create a proxy certificate for the client too.
@example
$ 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
@end example
Then start the server again:
@example
$ gnutls-serv --http \
--x509cafile x509-ca.pem \
--x509keyfile x509-server-key.pem \
--x509certfile x509-server.pem
@end example
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 ECDSA, you can also
create a ECDSA key and certificate for the server. These credentials
will be used in the final example below.
@example
$ certtool --generate-privkey --ecdsa > x509-server-key-ecc.pem
$ certtool --generate-certificate --load-privkey x509-server-key-ecc.pem \
--load-ca-certificate x509-ca.pem --load-ca-privkey x509-ca-key.pem \
--template server.tmpl --outfile x509-server-ecc.pem
@end example
The next step is to add support for SRP authentication. This requires
an SRP password file created with @code{srptool}.
To start the server with SRP support:
@example
gnutls-serv --http --priority NORMAL:+SRP-RSA:+SRP \
--srppasswdconf srp-tpasswd.conf \
--srppasswd srp-passwd.txt
@end example
Let's also start a server with support for PSK. This would require
a password file created with @code{psktool}.
@example
gnutls-serv --http --priority NORMAL:+ECDHE-PSK:+PSK \
--pskpasswd psk-passwd.txt
@end example
Finally, we start the server with all the earlier parameters and you
get this command:
@example
gnutls-serv --http --priority NORMAL:+PSK:+SRP \
--x509cafile x509-ca.pem \
--x509keyfile x509-server-key.pem \
--x509certfile x509-server.pem \
--x509keyfile x509-server-key-ecc.pem \
--x509certfile x509-server-ecc.pem \
--srppasswdconf srp-tpasswd.conf \
--srppasswd srp-passwd.txt \
--pskpasswd psk-passwd.txt
@end example
_EOF_;
};
|