/** @file
  Definition of IP6 option process routines.

  Copyright (c) 2009 - 2010, Intel Corporation. All rights reserved.<BR>

  This program and the accompanying materials
  are licensed and made available under the terms and conditions of the BSD License
  which accompanies this distribution.  The full text of the license may be found at
  http://opensource.org/licenses/bsd-license.php.

  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

#ifndef __EFI_IP6_OPTION_H__
#define __EFI_IP6_OPTION_H__

#define IP6_FRAGMENT_OFFSET_MASK (~0x3)

typedef struct _IP6_FRAGMENT_HEADER {
  UINT8                     NextHeader;
  UINT8                     Reserved;
  UINT16                    FragmentOffset;
  UINT32                    Identification;
} IP6_FRAGMENT_HEADER;

typedef struct _IP6_ROUTING_HEADER {
  UINT8                     NextHeader;
  UINT8                     HeaderLen;
  UINT8                     RoutingType;
  UINT8                     SegmentsLeft;
} IP6_ROUTING_HEADER;

typedef enum {
  Ip6OptionPad1             = 0,
  Ip6OptionPadN             = 1,
  Ip6OptionRouterAlert      = 5,
  Ip6OptionSkip             = 0,
  Ip6OptionDiscard          = 0x40,
  Ip6OptionParameterProblem = 0x80,
  Ip6OptionMask             = 0xc0,

  Ip6OptionEtherSource      = 1,
  Ip6OptionEtherTarget      = 2,
  Ip6OptionPrefixInfo       = 3,
  Ip6OptionRedirected       = 4,
  Ip6OptionMtu              = 5
} IP6_OPTION_TYPE;

/**
  Validate the IP6 extension header format for both the packets we received
  and that we will transmit. It will compute the ICMPv6 error message fields
  if the option is mal-formated.

  @param[in]  IpSb          The IP6 service instance. This is an optional parameter.
  @param[in]  Packet        The data of the packet. Ignored if NULL.
  @param[in]  NextHeader    The next header field in IPv6 basic header.
  @param[in]  ExtHdrs       The first byte of the option.
  @param[in]  ExtHdrsLen    The length of the whole option.
  @param[in]  Rcvd          The option is from the packet we received if TRUE,
                            otherwise, the option we want to transmit.
  @param[out] FormerHeader  The offset of NextHeader which points to Fragment
                            Header when we received, of the ExtHdrs.
                            Ignored if we transmit.
  @param[out] LastHeader    The pointer of NextHeader of the last extension
                            header processed by IP6.
  @param[out] RealExtsLen   The length of extension headers processed by IP6 layer.
                            This is an optional parameter that may be NULL.
  @param[out] UnFragmentLen The length of unfragmented length of extension headers.
                            This is an optional parameter that may be NULL.
  @param[out] Fragmented    Indicate whether the packet is fragmented.
                            This is an optional parameter that may be NULL.

  @retval     TRUE          The option is properly formated.
  @retval     FALSE         The option is malformated.

**/
BOOLEAN
Ip6IsExtsValid (
  IN IP6_SERVICE            *IpSb           OPTIONAL,
  IN NET_BUF                *Packet         OPTIONAL,
  IN UINT8                  *NextHeader,
  IN UINT8                  *ExtHdrs,
  IN UINT32                 ExtHdrsLen,
  IN BOOLEAN                Rcvd,
  OUT UINT32                *FormerHeader   OPTIONAL,
  OUT UINT8                 **LastHeader,
  OUT UINT32                *RealExtsLen    OPTIONAL,
  OUT UINT32                *UnFragmentLen  OPTIONAL,
  OUT BOOLEAN               *Fragmented     OPTIONAL
  );

/**
  Generate an IPv6 router alert option in network order and output it through Buffer.

  @param[out]     Buffer         Points to a buffer to record the generated option.
  @param[in, out] BufferLen      The length of Buffer, in bytes.
  @param[in]      NextHeader     The 8-bit selector indicates the type of header
                                 immediately following the Hop-by-Hop Options header.

  @retval EFI_BUFFER_TOO_SMALL   The Buffer is too small to contain the generated
                                 option. BufferLen is updated for the required size.

  @retval EFI_SUCCESS            The option is generated and filled in to Buffer.

**/
EFI_STATUS
Ip6FillHopByHop (
  OUT UINT8                  *Buffer,
  IN OUT UINTN               *BufferLen,
  IN UINT8                   NextHeader
  );

/**
  Insert a Fragment Header to the Extension headers and output it in UpdatedExtHdrs.

  @param[in]  IpSb             The IP6 service instance to transmit the packet.
  @param[in]  NextHeader       The extension header type of first extension header.
  @param[in]  LastHeader       The extension header type of last extension header.
  @param[in]  ExtHdrs          The length of the original extension header.
  @param[in]  ExtHdrsLen       The length of the extension headers.
  @param[in]  FragmentOffset   The fragment offset of the data following the header.
  @param[out] UpdatedExtHdrs   The updated ExtHdrs with Fragment header inserted.
                               It's caller's responsiblity to free this buffer.

  @retval EFI_OUT_OF_RESOURCES Failed to finish the operation due to lake of
                               resource.
  @retval EFI_UNSUPPORTED      The extension header specified in ExtHdrs is not
                               supported currently.
  @retval EFI_SUCCESS          The operation performed successfully.

**/
EFI_STATUS
Ip6FillFragmentHeader (
  IN  IP6_SERVICE           *IpSb,
  IN  UINT8                 NextHeader,
  IN  UINT8                 LastHeader,
  IN  UINT8                 *ExtHdrs,
  IN  UINT32                ExtHdrsLen,
  IN  UINT16                FragmentOffset,
  OUT UINT8                 **UpdatedExtHdrs
  );

/**
  Copy the extension headers from the original to buffer. A Fragment header is
  appended to the end.

  @param[in]       NextHeader       The 8-bit selector indicates the type of
                                    the fragment header's next header.
  @param[in]       ExtHdrs          The length of the original extension header.
  @param[in]       LastHeader       The pointer of next header of last extension header.
  @param[in]       FragmentOffset   The fragment offset of the data following the header.
  @param[in]       UnFragmentHdrLen The length of unfragmented length of extension headers.
  @param[in, out]  Buf              The buffer to copy options to.
  @param[in, out]  BufLen           The length of the buffer.

  @retval EFI_SUCCESS           The options are copied over.
  @retval EFI_BUFFER_TOO_SMALL  The buffer caller provided is too small.

**/
EFI_STATUS
Ip6CopyExts (
  IN UINT8                  NextHeader,
  IN UINT8                  *ExtHdrs,
  IN UINT8                  *LastHeader,
  IN UINT16                 FragmentOffset,
  IN UINT32                 UnFragmentHdrLen,
  IN OUT UINT8              *Buf,
  IN OUT UINT32             *BufLen
  );

/**
  Validate the IP6 option format for both the packets we received
  and that we will transmit. It supports the defined options in Neighbor
  Discovery messages.

  @param[in]  Option            The first byte of the option.
  @param[in]  OptionLen         The length of the whole option.

  @retval TRUE     The option is properly formatted.
  @retval FALSE    The option is malformated.

**/
BOOLEAN
Ip6IsNDOptionValid (
  IN UINT8                  *Option,
  IN UINT16                 OptionLen
  );

#endif