# SNMP::Info::IPv6
#
# Copyright (c) 2010 Jeroen van Ingen and Carlos Vicente
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
#     * Redistributions of source code must retain the above copyright notice,
#       this list of conditions and the following disclaimer.
#     * Redistributions in binary form must reproduce the above copyright
#       notice, this list of conditions and the following disclaimer in the
#       documentation and/or other materials provided with the distribution.
#     * Neither the name of the University of California, Santa Cruz nor the
#       names of its contributors may be used to endorse or promote products
#       derived from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
# LIABLE FOR # ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.

package SNMP::Info::IPv6;

use strict;
use warnings;
use Exporter;
use SNMP::Info;

@SNMP::Info::IPv6::ISA       = qw/SNMP::Info Exporter/;
@SNMP::Info::IPv6::EXPORT_OK = qw//;

our ($VERSION, %MIBS, %FUNCS, %GLOBALS, %MUNGE, $METHOD);

use constant {
    IPMIB   => 1,
    CISCO   => 2,
    IPV6MIB => 3,
};

$VERSION = '3.81';



%MIBS = (
    'IP-MIB'            => 'ipv6InterfaceTableLastChange',
    'IPV6-MIB'          => 'ipv6IfTableLastChange',
    'CISCO-IETF-IP-MIB' => 'cInetNetToMediaNetAddress',
);

%GLOBALS = ();

%FUNCS = (
    'ip_n2p_phys_addr'  => 'ipNetToPhysicalPhysAddress',    # IP-MIB
    'c_inet_phys_addr'  => 'cInetNetToMediaPhysAddress',    # CISCO-IETF-IP-MIB
    'i6_n2p_phys_addr'  => 'ipv6NetToMediaPhysAddress',     # IPV6-MIB

    'ip_n2p_phys_type'  => 'ipNetToPhysicalType',           # IP-MIB
    'c_inet_phys_type'  => 'cInetNetToMediaType',           # CISCO-IETF-IP-MIB
    'i6_n2p_phys_type'  => 'ipv6NetToMediaType',            # IPV6-MIB

    'ip_n2p_phys_state' => 'ipNetToPhysicalState',          # IP-MIB
    'c_inet_phys_state' => 'cInetNetToMediaState',          # CISCO-IETF-IP-MIB
    'i6_n2p_phys_state' => 'ipv6IfNetToMediaState',         # IPV6-MIB

    'ip_pfx_origin'     => 'ipAddressPrefixOrigin',         # IP-MIB
    'c_pfx_origin'      => 'cIpAddressPfxOrigin',           # CISCO-IETF-IP-MIB

    'ip_addr6_pfx'      => 'ipAddressPrefix',               # IP-MIB
    'c_addr6_pfx'       => 'cIpAddressPrefix',              # CISCO-IETF-IP-MIB

    # Commented out are not-accessible according to MIB
    #'ip_addr6_pfxlen'   => 'ipAddressPrefixLength',        # IP-MIB
    #'c_addr6_pfxlen'    => 'cIpAddressPfxLength',          # CISCO-IETF-IP-MIB
    'i6_addr_pfxlen'    => 'ipv6AddrPfxLength',             # IPV6-MIB

    'ip_addr6_index'    => 'ipAddressIfIndex',              # IP-MIB
    'c_addr6_index'     => 'cIpAddressIfIndex',             # CISCO-IETF-IP-MIB

    'ip_addr6_type'     => 'ipAddressType',                 # IP-MIB
    'c_addr6_type'      => 'cIpAddressType',                # CISCO-IETF-IP-MIB
);

%MUNGE = (
    'ip_n2p_phys_addr'  => \&SNMP::Info::munge_mac,
    'c_inet_phys_addr'  => \&munge_physaddr,
    'i6_n2p_phys_addr'  => \&SNMP::Info::munge_mac,
);


sub ipv6_n2p_mac {
    my $info = shift;
    my $return;
    my $phys_addr = &_test_methods( $info, {
        ip_n2p_phys_addr => IPMIB,
        c_inet_phys_addr => CISCO,
        i6_n2p_phys_addr => IPV6MIB,
    });
    return unless defined $phys_addr;
    foreach my $row (keys %$phys_addr) {
        if ($row =~ /^(\d+)\.(\d+)\.(\d+)\.([\d\.]+)$/) {
            my $ifindex = $1; my $addrtype = $2; my $addrsize = $3; my $v6addr = $4;
            if ($info::METHOD == IPV6MIB) {
                # IPV6-MIB doesn't include the addrtype in the index;
                # also, address syntax is IPv6Address (fixed 16 bytes) and not InetAddress (length field followed by address bytes)
                $v6addr = join('.', $addrtype, $addrsize, $v6addr);
                $addrtype = 2;
            }
            if (($addrtype == 2) && (defined $phys_addr->{$row})) { # IPv6
                $return->{$row} = substr($phys_addr->{$row}, 0, 17);
            }
        }
    }
    printf("%s: data comes from %s.\n", &_my_sub_name, $info->_method_used() ) if $info->debug();
    return $return;
}

sub ipv6_n2p_addr {
    my $info = shift;
    my $return;
    my $net_addr = &_test_methods( $info, {
        ip_n2p_phys_addr => IPMIB,
        c_inet_phys_addr => CISCO,
        i6_n2p_phys_addr => IPV6MIB,
    });
    return unless defined $net_addr;
    foreach my $row (keys %$net_addr) {
        if ($row =~ /^(\d+)\.(\d+)\.(\d+)\.([\d\.]+)$/) {
            my $ifindex = $1; my $addrtype = $2; my $addrsize = $3; my $v6addr = $4;
            if ($info::METHOD == IPV6MIB) {
                # IPV6-MIB doesn't include the addrtype in the index;
                # also, address syntax is IPv6Address (fixed 16 bytes) and not InetAddress (length field followed by address bytes)
                $v6addr = join('.', $addrtype, $addrsize, $v6addr);
                $addrtype = 2;
            }
            if ($addrtype == 2) { # IPv6
                my $v6_packed = pack("C*", split(/\./, $v6addr));
                if (length($v6_packed) == 15) {
                    # Workaround for some some IP-MIB implementations, eg on Cisco Nexus: no explicit addrsize,
                    # so what we've collected in that variable is actually the first byte of the address.
                    $v6_packed = pack('C', $addrsize) . $v6_packed;
                }
                if (length($v6_packed) == 17) {
                    # Workaround for IPV6-MIB on Windows 2012: if the address is one byte too long, the SNMP agent probably has an incorrect
                    # implementation where a length field precedes the actual IPv6 address.
                    # In that case, the first character should be chr(16), ie 0x10; strip it if that's the case.
                    $v6_packed =~ s/^\x10//;
                }
                if (length($v6_packed) == 16) {
                    $v6addr = join(':', map { sprintf("%04x", $_) } unpack("n*", $v6_packed) );
                    $return->{$row} = $v6addr;
                } else {
                    printf("Invalid size for IPv6 address: expected 16 bytes, got %d (%s = %s)\n", length($v6_packed), $row, $net_addr->{$row});
                }
            }
        }
    }
    printf("%s: data comes from %s.\n", &_my_sub_name, $info->_method_used() ) if $info->debug();
    return $return;
}

sub ipv6_n2p_if {
    my $info = shift;
    my $return;
    my $phys_addr = &_test_methods( $info, {
        ip_n2p_phys_addr => IPMIB,
        c_inet_phys_addr => CISCO,
        i6_n2p_phys_addr => IPV6MIB,
    });
    return unless defined $phys_addr;
    foreach my $row (keys %$phys_addr) {
        if ($row =~ /^(\d+)\.(\d+)\.(\d+)\.([\d\.]+)$/) {
            my $ifindex = $1; my $addrtype = $2; my $addrsize = $3; my $v6addr = $4;
            if ($info::METHOD == IPV6MIB) {
                # IPV6-MIB doesn't include the addrtype in the index;
                # also, address syntax is IPv6Address (fixed 16 bytes) and not InetAddress (length field followed by address bytes)
                $v6addr = join('.', $addrtype, $addrsize, $v6addr);
                $addrtype = 2;
            }
            if ($addrtype == 2) { # IPv6
                $return->{$row} = $ifindex;
            }
        }
    }
    printf("%s: data comes from %s.\n", &_my_sub_name, $info->_method_used() ) if $info->debug();
    return $return;
}

sub ipv6_n2p_type {
    my $info = shift;
    my $return;
    my $phys_type = &_test_methods( $info, {
        ip_n2p_phys_type => IPMIB,
        c_inet_phys_type => CISCO,
        i6_n2p_phys_type => IPV6MIB,
    });
    return unless defined $phys_type;
    foreach my $row (keys %$phys_type) {
        if ($row =~ /^(\d+)\.(\d+)\.(\d+)\.([\d\.]+)$/) {
            my $ifindex = $1; my $addrtype = $2; my $addrsize = $3; my $v6addr = $4;
            if ($info::METHOD == IPV6MIB) {
                # IPV6-MIB doesn't include the addrtype in the index;
                # also, address syntax is IPv6Address (fixed 16 bytes) and not InetAddress (length field followed by address bytes)
                $v6addr = join('.', $addrtype, $addrsize, $v6addr);
                $addrtype = 2;
            }
            if ($addrtype == 2) { # IPv6
                $return->{$row} = $phys_type->{$row};
            }
        }
    }
    printf("%s: data comes from %s.\n", &_my_sub_name, $info->_method_used() ) if $info->debug();
    return $return;
}

sub ipv6_n2p_state {
    my $info = shift;
    my $return;
    my $phys_state = &_test_methods( $info, {
        ip_n2p_phys_state => IPMIB,
        c_inet_phys_state => CISCO,
        i6_n2p_phys_state => IPV6MIB,
    });
    return unless defined $phys_state;
    foreach my $row (keys %$phys_state) {
        if ($row =~ /^(\d+)\.(\d+)\.(\d+)\.([\d\.]+)$/) {
            my $ifindex = $1; my $addrtype = $2; my $addrsize = $3; my $v6addr = $4;
            if ($info::METHOD == IPV6MIB) {
                # IPV6-MIB doesn't include the addrtype in the index;
                # also, address syntax is IPv6Address (fixed 16 bytes) and not InetAddress (length field followed by address bytes)
                $v6addr = join('.', $addrtype, $addrsize, $v6addr);
                $addrtype = 2;
            }
            if ($addrtype == 2) { # IPv6
                $return->{$row} = $phys_state->{$row};
            }
        }
    }
    printf("%s: data comes from %s.\n", &_my_sub_name, $info->_method_used() ) if $info->debug();
    return $return;
}

sub ipv6_index {
    my $info = shift;
    my $return;
    my $ipv6_index = &_test_methods( $info, {
	ip_addr6_index  => IPMIB,
	c_addr6_index   => CISCO,
				    });
    return unless defined $ipv6_index;
    foreach my $row (keys %$ipv6_index){
        if ($row =~ /^(\d+)\.([\d\.]+)$/) {
            my $addrtype = $1; my $v6addr = $2;
            if ($addrtype == 2) { # IPv6
		$return->{$row} = $ipv6_index->{$row};
	    }
	}
    }
    printf("%s: data comes from %s.\n", &_my_sub_name, $info->_method_used() ) if $info->debug();
    return $return;
}

sub ipv6_type {
    my $info = shift;
    my $return;
    my $ipv6_type = &_test_methods( $info, {
	ip_addr6_type  => IPMIB,
	c_addr6_type   => CISCO,
				    });
    return unless defined $ipv6_type;
    foreach my $row (keys %$ipv6_type){
        if ($row =~ /^(\d+)\.([\d\.]+)$/) {
            my $addrtype = $1; my $v6addr = $2;
            if ($addrtype == 2) { # IPv6
		$return->{$row} = $ipv6_type->{$row};
	    }
	}
    }
    printf("%s: data comes from %s.\n", &_my_sub_name, $info->_method_used() ) if $info->debug();
    return $return;
}

sub ipv6_pfx_origin {
    my $info = shift;
    my $return;
    my $ipv6_pfx_origin = &_test_methods( $info, {
	ip_pfx_origin  => IPMIB,
	c_pfx_origin   => CISCO,
				    });
    return unless defined $ipv6_pfx_origin;
    foreach my $row (keys %$ipv6_pfx_origin){
        if ($row =~ /^(\d+)\.(\d+)\.([\d\.]+)\.(\d+)$/) {
            my $ifindex = $1; my $type = $2; my $pfx = $3; my $len = $4;
            if ($type == 2) { # IPv6
		$return->{$row} = $ipv6_pfx_origin->{$row};
	    }
	}
    }
    printf("%s: data comes from %s.\n", &_my_sub_name, $info->_method_used() ) if $info->debug();
    return $return;
}

sub ipv6_addr_prefix {
    my $info = shift;
    my $return;
    my $ipv6_addr_prefix = &_test_methods( $info, {
	ip_addr6_pfx  => IPMIB,
	c_addr6_pfx   => CISCO,
				    });
    return unless defined $ipv6_addr_prefix;
    foreach my $row (keys %$ipv6_addr_prefix){
        if ($row =~ /^(\d+)\.[\d\.]+$/) {
            my $type = $1;
	    if (($type == 2) or ($type == 4)) { # IPv6
		# Remove interface specific part from vrf interfaces
		if ($row =~ /^((\d+\.){17}\d+)/) { $row = $1 }
		# Remove the OID part from the value
		my $val = $ipv6_addr_prefix->{$row};
		if ( $val =~ /^.+?((?:\d+\.){19}\d+)$/ ){
		    $val = $1;
		    $return->{$row} = $val;
		}
	    }
	}
    }
    printf("%s: data comes from %s.\n", &_my_sub_name, $info->_method_used() ) if $info->debug();
    return $return;
}

sub ipv6_addr_prefixlength {
    my $info = shift;
    my $return;
    my $ipv6_addr_prefix = &_test_methods( $info, {
        ip_addr6_pfx  => IPMIB,
        c_addr6_pfx   => CISCO,
    });
    return unless defined $ipv6_addr_prefix;
    foreach my $row (keys %$ipv6_addr_prefix) {
        if ($row =~ /^(\d+)\.[\d\.]+$/) {
            my $type = $1;
            if (($type == 2) or ($type == 4)) { # IPv6
                # Remove interface specific part from vrf interfaces
                if ($row =~ /^((\d+\.){17}\d+)/) { $row = $1 }
                # Remove the OID part from the value
                my $val = $ipv6_addr_prefix->{$row} || '';
                if ( $val =~ /^.+?((?:\d+\.){19}(\d+))$/ ) {
                    $val = $2;
                    $return->{$row} = $val;
                }
            }
        }
    }
    printf("%s: data comes from %s.\n", &_my_sub_name, $info->_method_used() ) if $info->debug();
    return $return;
}

sub ipv6_addr {
    my $info = shift;
    my $return = {};
    my $indexes = $info->ipv6_index();
    foreach my $row (keys %$indexes) {
        my @parts = split(/\./, $row);
        my $is_valid = 0;
        if (scalar @parts == 18) {
            my $addrtype = shift @parts;
            $is_valid = 1;
        } elsif (scalar @parts == 17) {
            $is_valid = 1;
        }
        my $addrsize = shift @parts; # First element now is addrsize, should be 16
        if ($is_valid && $addrsize == 16) {
            $return->{$row} = join(':', unpack('(H4)*', pack('C*', @parts)));
        } elsif ($info->debug()) {
            printf("%s: unable to decode table index to IPv6 address. Raw data is [%s].\n", &_my_sub_name, $row);
        }
    }
    return $return;
}

sub _method_used {
    my $info = shift;
    my $return = 'none of the MIBs';
    # FIXME ugh! a global. makes order of calls important for debug.
    if (defined $info::METHOD) {
        if ($info::METHOD eq IPMIB) {
            $return = 'IP-MIB';
        } elsif ($info::METHOD eq IPV6MIB) {
            $return = 'IPV6-MIB';
        } elsif ($info::METHOD eq CISCO) {
            $return = 'CISCO-IETF-IP-MIB';
        }
    }
    return $return;
}

sub _test_methods {
    my $info = shift;
    my $test = shift;
    my $return = {};
    foreach my $method (sort {$test->{$a} <=> $test->{$b}} keys %$test) {
        $return = $info->$method || {};
        if (scalar keys %$return) {
            # FIXME ugh! a global. makes order of calls important for debug.
            $info::METHOD = $test->{$method};
            last;
        }
    }
    return $return;
}

sub _my_sub_name {
    my @callinfo = caller(1);
    return $callinfo[3];
}

sub munge_physaddr {
    my $addr = shift;
    return unless defined $addr;
    return unless length $addr;
    $addr = join( ':', map { sprintf "%02x", $_ } unpack( 'C*', $addr ) );
    return $addr;
}

1;

__END__

=head1 NAME

SNMP::Info::IPv6 - SNMP Interface for obtaining IPv6 addresses and IPv6
address mappings

=head1 AUTHOR

Jeroen van Ingen and Carlos Vicente

=head1 SYNOPSIS

 # Let SNMP::Info determine the correct subclass for you.
 my $info = new SNMP::Info(
                          AutoSpecify => 1,
                          Debug       => 1,
                          DestHost    => 'myswitch',
                          Community   => 'public',
                          Version     => 2
                        )
    or die "Can't connect to DestHost.\n";

 my $class      = $info->class();
 print "SNMP::Info determined this device to fall under subclass : $class\n";

=head1 DESCRIPTION

The SNMP::Info::IPv6 class implements functions to for mapping IPv6 addresses
to MAC addresses, interfaces and more. It will use data from the F<IP-MIB>,
F<IPV6-MIB>, or the F<CISCO-IETF-IP-MIB>, whichever is supported by the
device.

This class is inherited by Info::Layer3 to provide IPv6 node tracking across
device classes.

For debugging purposes you can call this class directly as you would
SNMP::Info

 my $info = new SNMP::Info::IPv6 (...);

=head2 Inherited Classes

none.

=head2 Required MIBs

=over

=item F<IP-MIB>

=item F<IPV6-MIB>

=item F<CISCO-IETF-IP-MIB>

=back

=head1 GLOBALS

none.

=head1 TABLE METHODS

These are methods that return tables of information in the form of a reference
to a hash.

=head2  Internet Address Table

=over

=item $info->ipv6_n2p_addr()

=item $info->ipv6_n2p_if()

=item $info->ipv6_n2p_mac()

=item $info->ipv6_n2p_state()

=item $info->ipv6_n2p_type()

=item $info->ipv6_index()

Maps an IPv6 address to an interface C<ifIndex>

=item $info->ipv6_type()

Maps an IPv6 address to its type (unicast, anycast, etc.)

=item $info->ipv6_pfx_origin()

Maps an IPv6 prefix with its origin (manual, well-known, dhcp, etc.)

=item $info->ipv6_addr_prefix()

Maps IPv6 addresses with their prefixes

=item $info->ipv6_addr_prefixlength()

Maps IPv6 addresses with their prefix length

=item $info->ipv6_addr()

Maps a table instance to an IPv6 address

=back

=head2  Internet Address Translation Table

=over

=item $info->c_inet_phys_address()

Maps an address of type C<cInetNetToMediaNetAddressType> on interface C<ifIndex> to a physical address.

=back

=head1 MUNGES

=over

=item munge_physaddr()

Takes an octet stream (HEX-STRING) and returns a colon separated ASCII hex
string.

=back

=cut
