phpman > perldoc > Net::DNS::RR::RRSIG(3pm)

NAME
    Net::DNS::RR::RRSIG - DNS RRSIG resource record

SYNOPSIS
        use Net::DNS;
        $rr = Net::DNS::RR->new('name RRSIG typecovered algorithm labels
                                    orgttl sigexpiration siginception
                                    keytag signame signature');

        use Net::DNS::SEC;
        $sigrr = Net::DNS::RR::RRSIG->create( \@rrset, $keypath,
                                            sigex => 20211231010101
                                            sigin => 20211201010101
                                            );

        $sigrr->verify( \@rrset, $keyrr ) || die $sigrr->vrfyerrstr;

DESCRIPTION
    Class for DNS digital signature (RRSIG) resource records.

    In addition to the regular methods inherited from Net::DNS::RR the class contains a method to
    sign RRsets using private keys (create) and a method for verifying signatures over RRsets
    (verify).

    The RRSIG RR is an implementation of RFC4034. See Net::DNS::RR::SIG for an implementation of
    SIG0 (RFC2931).

METHODS
    The available methods are those inherited from the base class augmented by the type-specific
    methods defined in this package.

    Use of undocumented package features or direct access to internal data structures is discouraged
    and could result in program termination or other unpredictable behaviour.

  typecovered
        $typecovered = $rr->typecovered;

    The typecovered field identifies the type of the RRset that is covered by this RRSIG record.

  algorithm
        $algorithm = $rr->algorithm;

    The algorithm number field identifies the cryptographic algorithm used to create the signature.

    algorithm() may also be invoked as a class method or simple function to perform mnemonic and
    numeric code translation.

  labels
        $labels = $rr->labels;
        $rr->labels( $labels );

    The labels field specifies the number of labels in the original RRSIG RR owner name.

  orgttl
        $orgttl = $rr->orgttl;
        $rr->orgttl( $orgttl );

    The original TTL field specifies the TTL of the covered RRset as it appears in the authoritative
    zone.

  sigexpiration and siginception times
  sigex sigin sigval
        $expiration = $rr->sigexpiration;
        $expiration = $rr->sigexpiration( $value );

        $inception = $rr->siginception;
        $inception = $rr->siginception( $value );

    The signature expiration and inception fields specify a validity time interval for the
    signature.

    The value may be specified by a string with format 'yyyymmddhhmmss' or a Perl time() value.

    Return values are dual-valued, providing either a string value or numerical Perl time() value.

  keytag
        $keytag = $rr->keytag;
        $rr->keytag( $keytag );

    The keytag field contains the key tag value of the DNSKEY RR that validates this signature.

  signame
        $signame = $rr->signame;
        $rr->signame( $signame );

    The signer name field value identifies the owner name of the DNSKEY RR that a validator is
    supposed to use to validate this signature.

  signature
  sig
        $sig = $rr->sig;
        $rr->sig( $sig );

    The Signature field contains the cryptographic signature that covers the RRSIG RDATA (excluding
    the Signature field) and the RRset specified by the RRSIG owner name, RRSIG class, and RRSIG
    type covered fields.

  sigbin
        $sigbin = $rr->sigbin;
        $rr->sigbin( $sigbin );

    Binary representation of the cryptographic signature.

  create
    Create a signature over a RR set.

        use Net::DNS::SEC;

        $keypath = '/home/olaf/keys/Kbla.foo.+001+60114.private';

        $sigrr = Net::DNS::RR::RRSIG->create( \@rrsetref, $keypath );

        $sigrr = Net::DNS::RR::RRSIG->create( \@rrsetref, $keypath,
                                            sigex => 20211231010101
                                            sigin => 20211201010101
                                            );
        $sigrr->print;


        # Alternatively use Net::DNS::SEC::Private

        $private = Net::DNS::SEC::Private->new($keypath);

        $sigrr= Net::DNS::RR::RRSIG->create( \@rrsetref, $private );

    create() is an alternative constructor for a RRSIG RR object.

    This method returns an RRSIG with the signature over the subject rrset (an array of RRs) made
    with the private key stored in the key file.

    The first argument is a reference to an array that contains the RRset that needs to be signed.

    The second argument is a string which specifies the path to a file containing the private key as
    generated by dnssec-keygen.

    The optional remaining arguments consist of ( name => value ) pairs as follows:

            sigex  => 20211231010101,       # signature expiration
            sigin  => 20211201010101,       # signature inception
            sigval => 30,                   # validity window (days)
            ttl    => 3600                  # TTL

    The sigin and sigex values may be specified as Perl time values or as a string with the format
    'yyyymmddhhmmss'. The default for sigin is the time of signing.

    The sigval argument specifies the signature validity window in days ( sigex = sigin + sigval ).

    By default the signature is valid for 30 days.

    By default the TTL matches the RRset that is presented for signing.

  verify
        $verify = $sigrr->verify( $rrsetref, $keyrr );
        $verify = $sigrr->verify( $rrsetref, [$keyrr, $keyrr2, $keyrr3] );

    $rrsetref contains a reference to an array of RR objects and the method verifies the RRset
    against the signature contained in the $sigrr object itself using the public key in $keyrr.

    The second argument can either be a Net::DNS::RR::KEYRR object or a reference to an array of
    such objects. Verification will return successful as soon as one of the keys in the array leads
    to positive validation.

    Returns 0 on error and sets $sig->vrfyerrstr

  vrfyerrstr
        $verify = $sigrr->verify( $rrsetref, $keyrr );
        print $sigrr->vrfyerrstr unless $verify;

        $sigrr->verify( $rrsetref, $keyrr ) || die $sigrr->vrfyerrstr;

KEY GENERATION
    Private key files and corresponding public DNSKEY records are most conveniently generated using
    dnssec-keygen, a program that comes with the ISC BIND distribution.

        dnssec-keygen -a 10 -b 2048 -f ksk  rsa.example.
        dnssec-keygen -a 10 -b 1024         rsa.example.

        dnssec-keygen -a 14 -f ksk  ecdsa.example.
        dnssec-keygen -a 14         ecdsa.example.

    Do not change the name of the private key file. The create method uses the filename as generated
    by dnssec-keygen to determine the keyowner, algorithm, and the keyid (keytag).

REMARKS
    The code is not optimised for speed. It is probably not suitable to be used for signing large
    zones.

    If this code is still around in 2100 (not a leap year) you will need to check for proper
    handling of times after 28th February.

ACKNOWLEDGMENTS
    Although their original code may have disappeared following redesign of Net::DNS, Net::DNS::SEC
    and the OpenSSL API, the following individual contributors deserve to be recognised for their
    significant influence on the development of the RRSIG package.

    Andy Vaskys (Network Associates Laboratories) supplied code for RSA.

    T.J. Mather provided support for the DSA algorithm.

    Dick Franks added support for elliptic curve and Edwards curve algorithms.

    Mike McCauley created the Crypt::OpenSSL::ECDSA perl extension module specifically for this
    development.

COPYRIGHT
    Copyright (c)2001-2005 RIPE NCC, Olaf M. Kolkman

    Copyright (c)2007-2008 NLnet Labs, Olaf M. Kolkman

    Portions Copyright (c)2014 Dick Franks

    All rights reserved.

    Package template (c)2009,2012 O.M.Kolkman and R.W.Franks.

LICENSE
    Permission to use, copy, modify, and distribute this software and its documentation for any
    purpose and without fee is hereby granted, provided that the original copyright notices appear
    in all copies and that both copyright notice and this permission notice appear in supporting
    documentation, and that the name of the author not be used in advertising or publicity
    pertaining to distribution of the software without specific prior written permission.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
    BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
    NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
    DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

SEE ALSO
    perl, Net::DNS, Net::DNS::RR, Net::DNS::SEC, RFC4034

    Algorithm Numbers <http://www.iana.org/assignments/dns-sec-alg-numbers>

    BIND Administrator Reference Manual <http://bind.isc.org/>