NetworkPkg/Ip4Dxe/Ip4Option.h

/** @file
  IP4 option support routines.

Copyright (c) 2005 - 2018, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent

**/

#ifndef __EFI_IP4_OPTION_H__
#define __EFI_IP4_OPTION_H__

#define IP4_OPTION_EOP   0
#define IP4_OPTION_NOP   1
#define IP4_OPTION_LSRR  131       // Loss source and record routing,   10000011
#define IP4_OPTION_SSRR  137       // Strict source and record routing, 10001001
#define IP4_OPTION_RR    7         // Record routing, 00000111

#define IP4_OPTION_COPY_MASK  0x80

/**
  Validate the IP4 option format for both the packets we received
  and will transmit. It will compute the ICMP error message fields
  if the option is malformatted. But this information isn't used.

  @param[in]  Option            The first byte of the option
  @param[in]  OptionLen         The length of the whole option
  @param[in]  Rcvd              The option is from the packet we received if TRUE,
                                otherwise the option we wants to transmit.

  @retval TRUE     The option is properly formatted
  @retval FALSE    The option is malformatted

**/
BOOLEAN
Ip4OptionIsValid (
  IN UINT8    *Option,
  IN UINT32   OptionLen,
  IN BOOLEAN  Rcvd
  );

/**
  Copy the option from the original option to buffer. It
  handles the details such as:
  1. whether copy the single IP4 option to the first/non-first
     fragments.
  2. Pad the options copied over to aligned to 4 bytes.

  @param[in]       Option            The original option to copy from
  @param[in]       OptionLen         The length of the original option
  @param[in]       FirstFragment     Whether it is the first fragment
  @param[in, out]  Buf               The buffer to copy options to. NULL
  @param[in, out]  BufLen            The length of the buffer

  @retval EFI_SUCCESS           The options are copied over
  @retval EFI_BUFFER_TOO_SMALL  Buf is NULL or BufLen provided is too small.

**/
EFI_STATUS
Ip4CopyOption (
  IN     UINT8    *Option,
  IN     UINT32   OptionLen,
  IN     BOOLEAN  FirstFragment,
  IN OUT UINT8    *Buf            OPTIONAL,
  IN OUT UINT32   *BufLen
  );

#endif