NAME

    Crypt::TimestampedData - Read and write TimeStampedData files (.TSD,
    RFC 5544)

SYNOPSIS

      use Crypt::TimestampedData;
    
      # Decode from .TSD file
      my $tsd = Crypt::TimestampedData->read_file('/path/file.tsd');
      my $version           = $tsd->{version};
      my $data_uri          = $tsd->{dataUri};        # optional
      my $meta              = $tsd->{metaData};       # optional
      my $content_der       = $tsd->{content};        # optional (CMS ContentInfo DER)
      my $evidence_content  = $tsd->{temporalEvidence};
    
      # Encode to .TSD file
      Crypt::TimestampedData->write_file('/path/out.tsd', $tsd);

DESCRIPTION

    Minimal implementation of the TimeStampedData format (RFC 5544) using
    Convert::ASN1. This version treats CMS constructs and TimeStampTokens
    as opaque DER blobs. The goal is to enable reading/writing of .TSD
    files, delegating CMS/TS handling to external libraries when available.

METHODS

 new(%args)

    Creates a new Crypt::TimestampedData object with the provided
    arguments.

 read_file($filepath)

    Reads and decodes a .TSD file from the specified path. Returns a hash
    reference containing the decoded TimeStampedData structure.

 write_file($filepath, $tsd_hashref)

    Encodes and writes a TimeStampedData structure to the specified file
    path.

 decode_der($der)

    Decodes DER-encoded TimeStampedData. Handles both direct TSD format and
    CMS ContentInfo wrappers (id-ct-TSTData and pkcs7-signedData).

 encode_der($tsd_hashref)

    Encodes a TimeStampedData hash reference to DER format.

 extract_content_der($tsd_hashref)

    Extracts the embedded original content from TimeStampedData.content.
    Returns raw bytes of the original file if available, otherwise undef.

 extract_tst_tokens_der($tsd_hashref)

    Extracts RFC 3161 TimeStampToken(s) as DER ContentInfo blobs. Returns
    array reference of DER-encoded ContentInfo tokens.

 write_content_file($tsd_hashref, $filepath)

    Convenience method to write extracted content to a file.

 extract_signed_content_bytes($tsd_hashref)

    Extracts encapsulated content from a SignedData (p7m) stored in
    TSD.content. Returns raw bytes of the signed payload (eContent) when
    available.

 write_signed_content_file($tsd_hashref, $filepath)

    Convenience method to write extracted signed content to a file.

 write_tst_files($tsd_hashref, $dirpath)

    Writes extracted timestamp tokens to individual .tsr files in the
    specified directory.

 write_tds($marked_filepath, $tsr_input, $out_filepath_opt)

    Creates and writes a TSD file from a marked file and one or more
    RFC3161 TimeStampToken(s) provided as .TSR (DER CMS ContentInfo) blobs
    or paths.

EXAMPLES

      # Read a TSD file
      my $tsd = Crypt::TimestampedData->read_file('document.tsd');
      print "Version: $tsd->{version}\n";
      
      # Extract the original content
      Crypt::TimestampedData->write_content_file($tsd, 'original_document.pdf');
      
      # Extract timestamp tokens
      my $tokens = Crypt::TimestampedData->extract_tst_tokens_der($tsd);
      print "Found " . scalar(@$tokens) . " timestamp tokens\n";
      
      # Create a new TSD file
      my $output = Crypt::TimestampedData->write_tds(
        'document.pdf',           # original file
        'timestamp.tsr',          # timestamp token
        'document.tsd'           # output file
      );

COMMAND-LINE SCRIPTS

    This distribution includes several command-line scripts for working
    with TimeStampedData files:

      * tsd-create - Create a .tsd file from a file and timestamp

      * tsd-extract - Extract content and timestamps from a .tsd file

      * tsd-info - Display information about a .tsd file

 Windows Usage

    On Windows systems, scripts must be executed with Perl explicitly:

      perl tsd-create --help
      perl tsd-extract document.tsd
      perl tsd-info document.tsd

 Unix/Linux Usage

    On Unix/Linux systems, scripts can be executed directly:

      tsd-create --help
      tsd-extract document.tsd
      tsd-info document.tsd

REQUIREMENTS

      * Convert::ASN1

AUTHOR

    Guido Brugnara <gdo@leader.it> - created with AI support.

LICENSE

    This module is released under the same terms as Perl itself.

SEE ALSO

      * RFC 5544 - TimeStampedData Format

      * RFC 3161 - Internet X.509 Public Key Infrastructure Time-Stamp
      Protocol

      * RFC 5652 - Cryptographic Message Syntax (CMS)