=head1 NAME

Brocade::BSC::Const

=head1 SYNOPSIS

Symbolic constants used in BSC packages for well-known numbers
  (network protocols/header fields).

=head1 LICENCE AND COPYRIGHT

Copyright (c) 2015,  BROCADE COMMUNICATIONS SYSTEMS, INC

All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.

2. 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.

3. Neither the name of the copyright holder 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 HOLDER 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.

=cut

package Brocade::BSC::Const;

use strict;
use warnings;

use Readonly;

require Exporter;
our @ISA = qw(Exporter);
our @EXPORT_OK = qw($ETH_TYPE_IPv4       $ETH_TYPE_IPv6       $ETH_TYPE_ARP
                    $ETH_TYPE_MPLS_UCAST $ETH_TYPE_MPLS_MCAST $ETH_TYPE_LLDP
                    $ETH_TYPE_QINQ       $ETH_TYPE_DOT1AD     $ETH_TYPE_STAG
                    $ETH_TYPE_DOT1Q      $ETH_TYPE_CTAG
                    $IP_PROTO_ICMP       $IP_PROTO_TCP        $IP_PROTO_UDP
                    $IP_PROTO_TLSP       $IP_PROTO_ICMPv6
                    $IP_DSCP_CS0  $IP_DSCP_CS1  $IP_DSCP_CS2  $IP_DSCP_CS3
                    $IP_DSCP_CS4  $IP_DSCP_CS5  $IP_DSCP_CS6  $IP_DSCP_CS7
                    $IP_DSCP_AF11 $IP_DSCP_AF12 $IP_DSCP_AF13
                    $IP_DSCP_AF21 $IP_DSCP_AF22 $IP_DSCP_AF23
                    $IP_DSCP_AF31 $IP_DSCP_AF32 $IP_DSCP_AF33
                    $IP_DSCP_AF41 $IP_DSCP_AF42 $IP_DSCP_AF43
                    $IP_DSCP_EF
                    $IP_ECN_NON_ECT  $IP_ECN_ECT0  $IP_ECN_ECT1  $IP_ECN_CE
                    $ARP_REQUEST     $ARP_REPLY
                    $PCP_BE          $PCP_BK       $PCP_EE       $PCP_CA
                    $PCP_VI          $PCP_VO       $PCP_IC       $PCP_NC
);
our %EXPORT_TAGS = (all => [@EXPORT_OK]);


# Ethernet Types for some notable protocols
Readonly our $ETH_TYPE_IPv4       => 0x0800;    #  2048
Readonly our $ETH_TYPE_IPv6       => 0x86dd;    # 34525
Readonly our $ETH_TYPE_ARP        => 0x0806;    #  2054
Readonly our $ETH_TYPE_MPLS_UCAST => 0x8847;    # 34887
Readonly our $ETH_TYPE_MPLS_MCAST => 0x8848;    # 34888
Readonly our $ETH_TYPE_LLDP       => 0x88cc;    # 35020

Readonly our $ETH_TYPE_QINQ       => 0x88a8;    # 34984
Readonly our $ETH_TYPE_DOT1AD     => 0x88a8;    # 34984
Readonly our $ETH_TYPE_STAG       => 0x88a8;    # 34984

Readonly our $ETH_TYPE_DOT1Q      => 0x8100;    # 33024
Readonly our $ETH_TYPE_CTAG       => 0x8100;    # 33024

# IP protocol numbers
Readonly our $IP_PROTO_ICMP   => 0x01;  # ( 1) Internet Control Message Protocol
Readonly our $IP_PROTO_TCP    => 0x06;  # ( 6) Transmission Control Protocol
Readonly our $IP_PROTO_UDP    => 0x11;  # (17) User Datagram Protocol
Readonly our $IP_PROTO_TLSP   => 0x38;  # (56) Transport Layer Security Protocol
Readonly our $IP_PROTO_ICMPv6 => 0x3a;  # (58) ICMP for IPv6

# The IP Differentiated Services Code Points (DSCP)
# Class Selector (CS) are of the form 'xxx000'
# (higher value = higher priority)
#                                       | equiv IP precedence value
#                                       | -------------------------
Readonly our $IP_DSCP_CS0 => 0;         #  0   (Routine or Best Effort)
Readonly our $IP_DSCP_CS1 => 8;         #  1   (Priority)
Readonly our $IP_DSCP_CS2 => 16;        #  2   (Immediate)
Readonly our $IP_DSCP_CS3 => 24;        #  3   (Flash)
Readonly our $IP_DSCP_CS4 => 32;        #  4   (Flash Override)
Readonly our $IP_DSCP_CS5 => 40;        #  5   (Critical)
Readonly our $IP_DSCP_CS6 => 48;        #  6   (Internet)
Readonly our $IP_DSCP_CS7 => 56;        #  7   (Network)

# Assured Forwarding (AF) Per Hop Behavior (PHB) group
# The AF PHB group defines four separate classes
# Within each class, packets are given a drop precedence: high, medium or low
# Higher precedence means more dropping.
# AFxy (x=class, y=drop precedence)
# Class 1
Readonly our $IP_DSCP_AF11 => 10;
Readonly our $IP_DSCP_AF12 => 12;
Readonly our $IP_DSCP_AF13 => 14;
# Class 2
Readonly our $IP_DSCP_AF21 => 18;
Readonly our $IP_DSCP_AF22 => 20;
Readonly our $IP_DSCP_AF23 => 22;
# Class 3
Readonly our $IP_DSCP_AF31 => 26;
Readonly our $IP_DSCP_AF32 => 28;
Readonly our $IP_DSCP_AF33 => 30;
# Class 4
Readonly our $IP_DSCP_AF41 => 34;
Readonly our $IP_DSCP_AF42 => 36;
Readonly our $IP_DSCP_AF43 => 38;

# Expedited Forwarding
Readonly our $IP_DSCP_EF => 46;

# The Explicit Congestion Notification (ECN) 
# ECN uses the two least significant (right-most) bits of the DiffServ field
# in the IPv4 or IPv6 header to encode four different code points
Readonly our $IP_ECN_NON_ECT => 0;      # Non ECN-Capable Transport, NON-ECT
Readonly our $IP_ECN_ECT0    => 2;      # ECN Capable Transport, ECT(0)
Readonly our $IP_ECN_ECT1    => 1;      # ECN Capable Transport, ECT(1)
Readonly our $IP_ECN_CE      => 3;      # Congestion Encountered, CE

# ARP Operation Codes
Readonly our $ARP_REQUEST => 1;
Readonly our $ARP_REPLY   => 2;

# Ethernet frame Priority Code Points (PCP)
Readonly our $PCP_BE => 1;      # Best Effort            (priority 0, lowest)
Readonly our $PCP_BK => 0;      # Background             (priority 1)
Readonly our $PCP_EE => 2;      # Excellent Effort       (priority 2)
Readonly our $PCP_CA => 3;      # Critical Applications  (priority 3)
Readonly our $PCP_VI => 4;      # Video                  (priority 4)
Readonly our $PCP_VO => 5;      # Voice                  (priority 5)
Readonly our $PCP_IC => 6;      # Internetwork Control   (priority 6)
Readonly our $PCP_NC => 7;      # Network Control        (priority 7, highest)


# Module ===============================================================
1;
