=pod

=head1 NAME

tsget - Time Stamping HTTP/HTTPS client

=head1 SYNOPSIS

B<tsget>
B<-h> server_url
[B<-e> extension]
[B<-o> output]
[B<-v>]
[B<-d>]
[B<-k> private_key.pem]
[B<-p> key_password]
[B<-c> client_cert.pem]
[B<-C> CA_certs.pem]
[B<-P> CA_path]
[B<-r> file:file...]
[B<-g> EGD_socket]
[request]...

=head1 DESCRIPTION

The B<tsget> command can be used for sending a time stamp request, as
specified in B<RFC 3161>, to a time stamp server over HTTP or HTTPS and storing
the time stamp response in a file. This tool cannot be used for creating the
requests and verifying responses, you can use the OpenSSL B<ts(1)> command to
do that. B<tsget> can send several requests to the server without closing
the TCP connection if more than one requests are specified on the command
line.

The tool sends the following HTTP request for each time stamp request:

	POST url HTTP/1.1
	User-Agent: OpenTSA tsget.pl/<version>
	Host: <host>:<port>
	Pragma: no-cache
	Content-Type: application/timestamp-query
	Accept: application/timestamp-reply
	Content-Length: length of body

	...binary request specified by the user...

B<tsget> expects a response of type application/timestamp-reply, which is
written to a file without any interpretation.

=head1 OPTIONS

=over 4

=item B<-h> server_url

The URL of the HTTP/HTTPS server listening for time stamp requests.

=item B<-e> extension

If the B<-o> option is not given this argument specifies the extension of the
output files. The base name of the output file will be the same as those of
the input files. Default extension is '.tsr'. (Optional)

=item B<-o> output

This option can be specified only when just one request is sent to the
server. The time stamp response will be written to the given output file. '-'
means standard output. In case of multiple time stamp requests or the absence
of this argument the names of the output files will be derived from the names
of the input files and the default or specified extension argument. (Optional)

=item B<-v>

The name of the currently processed request is printed on standard
error. (Optional)

=item B<-d>

Switches on verbose mode for the underlying B<curl> library. You can see
detailed debug messages for the connection. (Optional)

=item B<-k> private_key.pem

(HTTPS) In case of certificate-based client authentication over HTTPS
<private_key.pem> must contain the private key of the user. The private key
file can optionally be protected by a passphrase. The B<-c> option must also
be specified. (Optional)

=item B<-p> key_password

(HTTPS) Specifies the passphrase for the private key specified by the B<-k>
argument. If this option is omitted and the key is passphrase protected B<tsget>
will ask for it. (Optional)

=item B<-c> client_cert.pem

(HTTPS) In case of certificate-based client authentication over HTTPS
<client_cert.pem> must contain the X.509 certificate of the user.  The B<-k>
option must also be specified. If this option is not specified no
certificate-based client authentication will take place. (Optional)

=item B<-C> CA_certs.pem

(HTTPS) The trusted CA certificate store. The certificate chain of the peer's
certificate must include one of the CA certificates specified in this file.
Either option B<-C> or option B<-P> must be given in case of HTTPS. (Optional)

=item B<-P> CA_path

(HTTPS) The path containing the trusted CA certificates to verify the peer's
certificate. The directory must be prepared with the B<c_rehash>
OpenSSL utility. Either option B<-C> or option B<-P> must be given in case of
HTTPS. (Optional)

=item B<-rand> file:file...

The files containing random data for seeding the random number
generator. Multiple files can be specified, the separator is B<;> for
MS-Windows, B<,> for VMS and B<:> for all other platforms. (Optional)

=item B<-g> EGD_socket

The name of an EGD socket to get random data from. (Optional)

=item [request]...

List of files containing B<RFC 3161> DER-encoded time stamp requests. If no
requests are specified only one request will be sent to the server and it will be
read from the standard input. (Optional)

=back

=head1 ENVIRONMENT VARIABLES

The B<TSGET> environment variable can optionally contain default
arguments. The content of this variable is added to the list of command line
arguments.

=head1 EXAMPLES

The examples below presume that B<file1.tsq> and B<file2.tsq> contain valid
time stamp requests, tsa.opentsa.org listens at port 8080 for HTTP requests
and at port 8443 for HTTPS requests, the TSA service is available at the /tsa
absolute path.

Get a time stamp response for file1.tsq over HTTP, output is written to 
file1.tsr:

  tsget -h http://tsa.opentsa.org:8080/tsa file1.tsq

Get a time stamp response for file1.tsq and file2.tsq over HTTP showing
progress, output is written to file1.reply and file2.reply respectively:

  tsget -h http://tsa.opentsa.org:8080/tsa -v -e .reply \
	file1.tsq file2.tsq

Create a time stamp request, write it to file3.tsq, send it to the server and
write the response to file3.tsr:

  openssl ts -query -data file3.txt -cert | tee file3.tsq \
	| tsget -h http://tsa.opentsa.org:8080/tsa \
	-o file3.tsr

Get a time stamp response for file1.tsq over HTTPS without client
authentication:

  tsget -h https://tsa.opentsa.org:8443/tsa \
	-C cacerts.pem file1.tsq

Get a time stamp response for file1.tsq over HTTPS with certificate-based
client authentication (it will ask for the passphrase if client_key.pem is
protected):

  tsget -h https://tsa.opentsa.org:8443/tsa -C cacerts.pem \
	-k client_key.pem -c client_cert.pem file1.tsq

You can shorten the previous command line if you make use of the B<TSGET>
environment variable. The following commands do the same as the previous
example:

  TSGET='-h https://tsa.opentsa.org:8443/tsa -C cacerts.pem \
	-k client_key.pem -c client_cert.pem'
  export TSGET
  tsget file1.tsq

=head1 AUTHOR

Zoltan Glozik <zglozik@opentsa.org>, OpenTSA project (http://www.opentsa.org)

=head1 SEE ALSO

L<openssl(1)|openssl(1)>, L<ts(1)|ts(1)>, L<curl(1)|curl(1)>, 
B<RFC 3161>

=cut