[mirror_edk2.git] / NetworkPkg / UefiPxeBcDxe / PxeBcDhcp4.c

/** @file\r
  Functions implementation related with DHCPv4 for UefiPxeBc Driver.\r
\r
  Copyright (c) 2009 - 2018, Intel Corporation. All rights reserved.<BR>\r
\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include "PxeBcImpl.h"\r
\r
//\r
// This is a map from the interested DHCP4 option tags' index to the tag value.\r
//\r
UINT8  mInterestedDhcp4Tags[PXEBC_DHCP4_TAG_INDEX_MAX] = {\r
  DHCP4_TAG_BOOTFILE_LEN,\r
  DHCP4_TAG_VENDOR,\r
  DHCP4_TAG_OVERLOAD,\r
  DHCP4_TAG_MSG_TYPE,\r
  DHCP4_TAG_SERVER_ID,\r
  DHCP4_TAG_VENDOR_CLASS_ID,\r
  DHCP4_TAG_BOOTFILE\r
};\r
\r
//\r
// There are 4 times retries with the value of 4, 8, 16 and 32, refers to PXE2.1 spec.\r
//\r
UINT32  mPxeDhcpTimeout[4] = { 4, 8, 16, 32 };\r
\r
/**\r
  Parse a certain dhcp4 option by OptTag in Buffer, and return with start pointer.\r
\r
  @param[in]  Buffer              Pointer to the option buffer.\r
  @param[in]  Length              Length of the option buffer.\r
  @param[in]  OptTag              Tag of the required option.\r
\r
  @retval     NULL                Failed to find the required option.\r
  @retval     Others              The position of the required option.\r
\r
**/\r
EFI_DHCP4_PACKET_OPTION *\r
PxeBcParseDhcp4Options (\r
  IN UINT8   *Buffer,\r
  IN UINT32  Length,\r
  IN UINT8   OptTag\r
  )\r
{\r
  EFI_DHCP4_PACKET_OPTION  *Option;\r
  UINT32                   Offset;\r
\r
  Option = (EFI_DHCP4_PACKET_OPTION *)Buffer;\r
  Offset = 0;\r
\r
  while (Offset < Length && Option->OpCode != DHCP4_TAG_EOP) {\r
    if (Option->OpCode == OptTag) {\r
      //\r
      // Found the required option.\r
      //\r
      return Option;\r
    }\r
\r
    //\r
    // Skip the current option to the next.\r
    //\r
    if (Option->OpCode == DHCP4_TAG_PAD) {\r
      Offset++;\r
    } else {\r
      Offset += Option->Length + 2;\r
    }\r
\r
    Option = (EFI_DHCP4_PACKET_OPTION *)(Buffer + Offset);\r
  }\r
\r
  return NULL;\r
}\r
\r
/**\r
  Parse the PXE vendor options and extract the information from them.\r
\r
  @param[in]  Dhcp4Option        Pointer to vendor options in buffer.\r
  @param[in]  VendorOption       Pointer to structure to store information in vendor options.\r
\r
**/\r
VOID\r
PxeBcParseVendorOptions (\r
  IN EFI_DHCP4_PACKET_OPTION  *Dhcp4Option,\r
  IN PXEBC_VENDOR_OPTION      *VendorOption\r
  )\r
{\r
  UINT32                   *BitMap;\r
  UINT8                    VendorOptionLen;\r
  EFI_DHCP4_PACKET_OPTION  *PxeOption;\r
  UINT8                    Offset;\r
\r
  BitMap          = VendorOption->BitMap;\r
  VendorOptionLen = Dhcp4Option->Length;\r
  PxeOption       = (EFI_DHCP4_PACKET_OPTION *)&Dhcp4Option->Data[0];\r
  Offset          = 0;\r
\r
  ASSERT (PxeOption != NULL);\r
\r
  while ((Offset < VendorOptionLen) && (PxeOption->OpCode != DHCP4_TAG_EOP)) {\r
    //\r
    // Parse all the interesting PXE vendor options one by one.\r
    //\r
    switch (PxeOption->OpCode) {\r
      case PXEBC_VENDOR_TAG_MTFTP_IP:\r
\r
        CopyMem (&VendorOption->MtftpIp, PxeOption->Data, sizeof (EFI_IPv4_ADDRESS));\r
        break;\r
\r
      case PXEBC_VENDOR_TAG_MTFTP_CPORT:\r
\r
        CopyMem (&VendorOption->MtftpCPort, PxeOption->Data, sizeof (VendorOption->MtftpCPort));\r
        break;\r
\r
      case PXEBC_VENDOR_TAG_MTFTP_SPORT:\r
\r
        CopyMem (&VendorOption->MtftpSPort, PxeOption->Data, sizeof (VendorOption->MtftpSPort));\r
        break;\r
\r
      case PXEBC_VENDOR_TAG_MTFTP_TIMEOUT:\r
\r
        VendorOption->MtftpTimeout = *PxeOption->Data;\r
        break;\r
\r
      case PXEBC_VENDOR_TAG_MTFTP_DELAY:\r
\r
        VendorOption->MtftpDelay = *PxeOption->Data;\r
        break;\r
\r
      case PXEBC_VENDOR_TAG_DISCOVER_CTRL:\r
\r
        VendorOption->DiscoverCtrl = *PxeOption->Data;\r
        break;\r
\r
      case PXEBC_VENDOR_TAG_DISCOVER_MCAST:\r
\r
        CopyMem (&VendorOption->DiscoverMcastIp, PxeOption->Data, sizeof (EFI_IPv4_ADDRESS));\r
        break;\r
\r
      case PXEBC_VENDOR_TAG_BOOT_SERVERS:\r
\r
        VendorOption->BootSvrLen = PxeOption->Length;\r
        VendorOption->BootSvr    = (PXEBC_BOOT_SVR_ENTRY *)PxeOption->Data;\r
        break;\r
\r
      case PXEBC_VENDOR_TAG_BOOT_MENU:\r
\r
        VendorOption->BootMenuLen = PxeOption->Length;\r
        VendorOption->BootMenu    = (PXEBC_BOOT_MENU_ENTRY *)PxeOption->Data;\r
        break;\r
\r
      case PXEBC_VENDOR_TAG_MENU_PROMPT:\r
\r
        VendorOption->MenuPromptLen = PxeOption->Length;\r
        VendorOption->MenuPrompt    = (PXEBC_MENU_PROMPT *)PxeOption->Data;\r
        break;\r
\r
      case PXEBC_VENDOR_TAG_MCAST_ALLOC:\r
\r
        CopyMem (&VendorOption->McastIpBase, PxeOption->Data, sizeof (EFI_IPv4_ADDRESS));\r
        CopyMem (&VendorOption->McastIpBlock, PxeOption->Data + 4, sizeof (VendorOption->McastIpBlock));\r
        CopyMem (&VendorOption->McastIpRange, PxeOption->Data + 6, sizeof (VendorOption->McastIpRange));\r
        break;\r
\r
      case PXEBC_VENDOR_TAG_CREDENTIAL_TYPES:\r
\r
        VendorOption->CredTypeLen = PxeOption->Length;\r
        VendorOption->CredType    = (UINT32 *)PxeOption->Data;\r
        break;\r
\r
      case PXEBC_VENDOR_TAG_BOOT_ITEM:\r
\r
        CopyMem (&VendorOption->BootSrvType, PxeOption->Data, sizeof (VendorOption->BootSrvType));\r
        CopyMem (&VendorOption->BootSrvLayer, PxeOption->Data + 2, sizeof (VendorOption->BootSrvLayer));\r
        break;\r
\r
      default:\r
        //\r
        // Not interesting PXE vendor options.\r
        //\r
        break;\r
    }\r
\r
    //\r
    // Set the bit map for the special PXE options.\r
    //\r
    SET_VENDOR_OPTION_BIT_MAP (BitMap, PxeOption->OpCode);\r
\r
    //\r
    // Continue to the next option.\r
    //\r
    if (PxeOption->OpCode == DHCP4_TAG_PAD) {\r
      Offset++;\r
    } else {\r
      Offset = (UINT8)(Offset + PxeOption->Length + 2);\r
    }\r
\r
    PxeOption = (EFI_DHCP4_PACKET_OPTION *)(Dhcp4Option->Data + Offset);\r
  }\r
}\r
\r
/**\r
  Build the options buffer for the DHCPv4 request packet.\r
\r
  @param[in]  Private             Pointer to PxeBc private data.\r
  @param[out] OptList             Pointer to the option pointer array.\r
  @param[in]  Buffer              Pointer to the buffer to contain the option list.\r
  @param[in]  NeedMsgType         If TRUE, it is necessary to include the Msg type option.\r
                                  Otherwise, it is not necessary.\r
\r
  @return     Index               The count of the built-in options.\r
\r
**/\r
UINT32\r
PxeBcBuildDhcp4Options (\r
  IN  PXEBC_PRIVATE_DATA       *Private,\r
  OUT EFI_DHCP4_PACKET_OPTION  **OptList,\r
  IN  UINT8                    *Buffer,\r
  IN  BOOLEAN                  NeedMsgType\r
  )\r
{\r
  UINT32                    Index;\r
  PXEBC_DHCP4_OPTION_ENTRY  OptEnt;\r
  UINT16                    Value;\r
\r
  Index      = 0;\r
  OptList[0] = (EFI_DHCP4_PACKET_OPTION *)Buffer;\r
\r
  if (NeedMsgType) {\r
    //\r
    // Append message type.\r
    //\r
    OptList[Index]->OpCode = DHCP4_TAG_MSG_TYPE;\r
    OptList[Index]->Length = 1;\r
    OptEnt.Mesg            = (PXEBC_DHCP4_OPTION_MESG *)OptList[Index]->Data;\r
    OptEnt.Mesg->Type      = PXEBC_DHCP4_MSG_TYPE_REQUEST;\r
    Index++;\r
    OptList[Index] = GET_NEXT_DHCP_OPTION (OptList[Index - 1]);\r
\r
    //\r
    // Append max message size.\r
    //\r
    OptList[Index]->OpCode = DHCP4_TAG_MAXMSG;\r
    OptList[Index]->Length = (UINT8)sizeof (PXEBC_DHCP4_OPTION_MAX_MESG_SIZE);\r
    OptEnt.MaxMesgSize     = (PXEBC_DHCP4_OPTION_MAX_MESG_SIZE *)OptList[Index]->Data;\r
    Value                  = NTOHS (PXEBC_DHCP4_PACKET_MAX_SIZE);\r
    CopyMem (&OptEnt.MaxMesgSize->Size, &Value, sizeof (UINT16));\r
    Index++;\r
    OptList[Index] = GET_NEXT_DHCP_OPTION (OptList[Index - 1]);\r
  }\r
\r
  //\r
  // Append parameter request list option.\r
  //\r
  OptList[Index]->OpCode    = DHCP4_TAG_PARA_LIST;\r
  OptList[Index]->Length    = 35;\r
  OptEnt.Para               = (PXEBC_DHCP4_OPTION_PARA *)OptList[Index]->Data;\r
  OptEnt.Para->ParaList[0]  = DHCP4_TAG_NETMASK;\r
  OptEnt.Para->ParaList[1]  = DHCP4_TAG_TIME_OFFSET;\r
  OptEnt.Para->ParaList[2]  = DHCP4_TAG_ROUTER;\r
  OptEnt.Para->ParaList[3]  = DHCP4_TAG_TIME_SERVER;\r
  OptEnt.Para->ParaList[4]  = DHCP4_TAG_NAME_SERVER;\r
  OptEnt.Para->ParaList[5]  = DHCP4_TAG_DNS_SERVER;\r
  OptEnt.Para->ParaList[6]  = DHCP4_TAG_HOSTNAME;\r
  OptEnt.Para->ParaList[7]  = DHCP4_TAG_BOOTFILE_LEN;\r
  OptEnt.Para->ParaList[8]  = DHCP4_TAG_DOMAINNAME;\r
  OptEnt.Para->ParaList[9]  = DHCP4_TAG_ROOTPATH;\r
  OptEnt.Para->ParaList[10] = DHCP4_TAG_EXTEND_PATH;\r
  OptEnt.Para->ParaList[11] = DHCP4_TAG_EMTU;\r
  OptEnt.Para->ParaList[12] = DHCP4_TAG_TTL;\r
  OptEnt.Para->ParaList[13] = DHCP4_TAG_BROADCAST;\r
  OptEnt.Para->ParaList[14] = DHCP4_TAG_NIS_DOMAIN;\r
  OptEnt.Para->ParaList[15] = DHCP4_TAG_NIS_SERVER;\r
  OptEnt.Para->ParaList[16] = DHCP4_TAG_NTP_SERVER;\r
  OptEnt.Para->ParaList[17] = DHCP4_TAG_VENDOR;\r
  OptEnt.Para->ParaList[18] = DHCP4_TAG_REQUEST_IP;\r
  OptEnt.Para->ParaList[19] = DHCP4_TAG_LEASE;\r
  OptEnt.Para->ParaList[20] = DHCP4_TAG_SERVER_ID;\r
  OptEnt.Para->ParaList[21] = DHCP4_TAG_T1;\r
  OptEnt.Para->ParaList[22] = DHCP4_TAG_T2;\r
  OptEnt.Para->ParaList[23] = DHCP4_TAG_VENDOR_CLASS_ID;\r
  OptEnt.Para->ParaList[24] = DHCP4_TAG_TFTP;\r
  OptEnt.Para->ParaList[25] = DHCP4_TAG_BOOTFILE;\r
  OptEnt.Para->ParaList[26] = DHCP4_TAG_UUID;\r
  OptEnt.Para->ParaList[27] = 0x80;\r
  OptEnt.Para->ParaList[28] = 0x81;\r
  OptEnt.Para->ParaList[29] = 0x82;\r
  OptEnt.Para->ParaList[30] = 0x83;\r
  OptEnt.Para->ParaList[31] = 0x84;\r
  OptEnt.Para->ParaList[32] = 0x85;\r
  OptEnt.Para->ParaList[33] = 0x86;\r
  OptEnt.Para->ParaList[34] = 0x87;\r
  Index++;\r
  OptList[Index] = GET_NEXT_DHCP_OPTION (OptList[Index - 1]);\r
\r
  //\r
  // Append UUID/Guid-based client identifier option\r
  //\r
  OptList[Index]->OpCode = DHCP4_TAG_UUID;\r
  OptList[Index]->Length = (UINT8)sizeof (PXEBC_DHCP4_OPTION_UUID);\r
  OptEnt.Uuid            = (PXEBC_DHCP4_OPTION_UUID *)OptList[Index]->Data;\r
  OptEnt.Uuid->Type      = 0;\r
  Index++;\r
  OptList[Index] = GET_NEXT_DHCP_OPTION (OptList[Index - 1]);\r
\r
  if (EFI_ERROR (NetLibGetSystemGuid ((EFI_GUID *)OptEnt.Uuid->Guid))) {\r
    //\r
    // Zero the Guid to indicate NOT programmable if failed to get system Guid.\r
    //\r
    DEBUG ((DEBUG_WARN, "PXE: Failed to read system GUID from the smbios table!\n"));\r
    ZeroMem (OptEnt.Uuid->Guid, sizeof (EFI_GUID));\r
  }\r
\r
  //\r
  // Append client network device interface option\r
  //\r
  OptList[Index]->OpCode = DHCP4_TAG_UNDI;\r
  OptList[Index]->Length = (UINT8)sizeof (PXEBC_DHCP4_OPTION_UNDI);\r
  OptEnt.Undi            = (PXEBC_DHCP4_OPTION_UNDI *)OptList[Index]->Data;\r
\r
  if (Private->Nii != NULL) {\r
    OptEnt.Undi->Type     = Private->Nii->Type;\r
    OptEnt.Undi->MajorVer = Private->Nii->MajorVer;\r
    OptEnt.Undi->MinorVer = Private->Nii->MinorVer;\r
  } else {\r
    OptEnt.Undi->Type     = DEFAULT_UNDI_TYPE;\r
    OptEnt.Undi->MajorVer = DEFAULT_UNDI_MAJOR;\r
    OptEnt.Undi->MinorVer = DEFAULT_UNDI_MINOR;\r
  }\r
\r
  Index++;\r
  OptList[Index] = GET_NEXT_DHCP_OPTION (OptList[Index - 1]);\r
\r
  //\r
  // Append client system architecture option\r
  //\r
  OptList[Index]->OpCode = DHCP4_TAG_ARCH;\r
  OptList[Index]->Length = (UINT8)sizeof (PXEBC_DHCP4_OPTION_ARCH);\r
  OptEnt.Arch            = (PXEBC_DHCP4_OPTION_ARCH *)OptList[Index]->Data;\r
  Value                  = HTONS (EFI_PXE_CLIENT_SYSTEM_ARCHITECTURE);\r
  CopyMem (&OptEnt.Arch->Type, &Value, sizeof (UINT16));\r
  Index++;\r
  OptList[Index] = GET_NEXT_DHCP_OPTION (OptList[Index - 1]);\r
\r
  //\r
  // Append vendor class identify option\r
  //\r
  OptList[Index]->OpCode = DHCP4_TAG_VENDOR_CLASS_ID;\r
  OptList[Index]->Length = (UINT8)sizeof (PXEBC_DHCP4_OPTION_CLID);\r
  OptEnt.Clid            = (PXEBC_DHCP4_OPTION_CLID *)OptList[Index]->Data;\r
  CopyMem (\r
    OptEnt.Clid,\r
    DEFAULT_CLASS_ID_DATA,\r
    sizeof (PXEBC_DHCP4_OPTION_CLID)\r
    );\r
  PxeBcUintnToAscDecWithFormat (\r
    EFI_PXE_CLIENT_SYSTEM_ARCHITECTURE,\r
    OptEnt.Clid->ArchitectureType,\r
    sizeof (OptEnt.Clid->ArchitectureType)\r
    );\r
\r
  if (Private->Nii != NULL) {\r
    CopyMem (OptEnt.Clid->InterfaceName, Private->Nii->StringId, sizeof (OptEnt.Clid->InterfaceName));\r
    PxeBcUintnToAscDecWithFormat (Private->Nii->MajorVer, OptEnt.Clid->UndiMajor, sizeof (OptEnt.Clid->UndiMajor));\r
    PxeBcUintnToAscDecWithFormat (Private->Nii->MinorVer, OptEnt.Clid->UndiMinor, sizeof (OptEnt.Clid->UndiMinor));\r
  }\r
\r
  Index++;\r
\r
  return Index;\r
}\r
\r
/**\r
  Create a template DHCPv4 packet as a seed.\r
\r
  @param[out] Seed           Pointer to the seed packet.\r
  @param[in]  Udp4           Pointer to EFI_UDP4_PROTOCOL.\r
\r
**/\r
VOID\r
PxeBcSeedDhcp4Packet (\r
  OUT EFI_DHCP4_PACKET   *Seed,\r
  IN  EFI_UDP4_PROTOCOL  *Udp4\r
  )\r
{\r
  EFI_SIMPLE_NETWORK_MODE  Mode;\r
  EFI_DHCP4_HEADER         *Header;\r
\r
  //\r
  // Get IfType and HwAddressSize from SNP mode data.\r
  //\r
  Udp4->GetModeData (Udp4, NULL, NULL, NULL, &Mode);\r
\r
  Seed->Size   = sizeof (EFI_DHCP4_PACKET);\r
  Seed->Length = sizeof (Seed->Dhcp4);\r
  Header       = &Seed->Dhcp4.Header;\r
  ZeroMem (Header, sizeof (EFI_DHCP4_HEADER));\r
  Header->OpCode    = PXEBC_DHCP4_OPCODE_REQUEST;\r
  Header->HwType    = Mode.IfType;\r
  Header->HwAddrLen = (UINT8)Mode.HwAddressSize;\r
  CopyMem (Header->ClientHwAddr, &Mode.CurrentAddress, Header->HwAddrLen);\r
\r
  Seed->Dhcp4.Magik     = PXEBC_DHCP4_MAGIC;\r
  Seed->Dhcp4.Option[0] = DHCP4_TAG_EOP;\r
}\r
\r
/**\r
  Cache the DHCPv4 packet.\r
\r
  @param[in]  Dst          Pointer to the cache buffer for DHCPv4 packet.\r
  @param[in]  Src          Pointer to the DHCPv4 packet to be cached.\r
\r
  @retval     EFI_SUCCESS                Packet is copied.\r
  @retval     EFI_BUFFER_TOO_SMALL       Cache buffer is not big enough to hold the packet.\r
\r
**/\r
EFI_STATUS\r
PxeBcCacheDhcp4Packet (\r
  IN EFI_DHCP4_PACKET  *Dst,\r
  IN EFI_DHCP4_PACKET  *Src\r
  )\r
{\r
  if (Dst->Size < Src->Length) {\r
    return EFI_BUFFER_TOO_SMALL;\r
  }\r
\r
  CopyMem (&Dst->Dhcp4, &Src->Dhcp4, Src->Length);\r
  Dst->Length = Src->Length;\r
\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  Parse the cached DHCPv4 packet, including all the options.\r
\r
  @param[in]  Cache4           Pointer to cached DHCPv4 packet.\r
\r
  @retval     EFI_SUCCESS      Parsed the DHCPv4 packet successfully.\r
  @retval     EFI_DEVICE_ERROR Failed to parse and invalid packet.\r
\r
**/\r
EFI_STATUS\r
PxeBcParseDhcp4Packet (\r
  IN PXEBC_DHCP4_PACKET_CACHE  *Cache4\r
  )\r
{\r
  EFI_DHCP4_PACKET         *Offer;\r
  EFI_DHCP4_PACKET_OPTION  **Options;\r
  EFI_DHCP4_PACKET_OPTION  *Option;\r
  PXEBC_OFFER_TYPE         OfferType;\r
  UINTN                    Index;\r
  BOOLEAN                  IsProxyOffer;\r
  BOOLEAN                  IsPxeOffer;\r
  UINT8                    *Ptr8;\r
  BOOLEAN                  FileFieldOverloaded;\r
\r
  IsProxyOffer        = FALSE;\r
  IsPxeOffer          = FALSE;\r
  FileFieldOverloaded = FALSE;\r
\r
  ZeroMem (Cache4->OptList, sizeof (Cache4->OptList));\r
  ZeroMem (&Cache4->VendorOpt, sizeof (Cache4->VendorOpt));\r
\r
  Offer   = &Cache4->Packet.Offer;\r
  Options = Cache4->OptList;\r
\r
  //\r
  // Parse DHCPv4 options in this offer, and store the pointers.\r
  // First, try to parse DHCPv4 options from the DHCP optional parameters field.\r
  //\r
  for (Index = 0; Index < PXEBC_DHCP4_TAG_INDEX_MAX; Index++) {\r
    Options[Index] = PxeBcParseDhcp4Options (\r
                       Offer->Dhcp4.Option,\r
                       GET_OPTION_BUFFER_LEN (Offer),\r
                       mInterestedDhcp4Tags[Index]\r
                       );\r
  }\r
\r
  //\r
  // Second, Check if bootfilename and serverhostname is overloaded to carry DHCP options refers to rfc-2132.\r
  // If yes, try to parse options from the BootFileName field, then ServerName field.\r
  //\r
  Option = Options[PXEBC_DHCP4_TAG_INDEX_OVERLOAD];\r
  if (Option != NULL) {\r
    if ((Option->Data[0] & PXEBC_DHCP4_OVERLOAD_FILE) != 0) {\r
      FileFieldOverloaded = TRUE;\r
      for (Index = 0; Index < PXEBC_DHCP4_TAG_INDEX_MAX; Index++) {\r
        if (Options[Index] == NULL) {\r
          Options[Index] = PxeBcParseDhcp4Options (\r
                             (UINT8 *)Offer->Dhcp4.Header.BootFileName,\r
                             sizeof (Offer->Dhcp4.Header.BootFileName),\r
                             mInterestedDhcp4Tags[Index]\r
                             );\r
        }\r
      }\r
    }\r
\r
    if ((Option->Data[0] & PXEBC_DHCP4_OVERLOAD_SERVER_NAME) != 0) {\r
      for (Index = 0; Index < PXEBC_DHCP4_TAG_INDEX_MAX; Index++) {\r
        if (Options[Index] == NULL) {\r
          Options[Index] = PxeBcParseDhcp4Options (\r
                             (UINT8 *)Offer->Dhcp4.Header.ServerName,\r
                             sizeof (Offer->Dhcp4.Header.ServerName),\r
                             mInterestedDhcp4Tags[Index]\r
                             );\r
        }\r
      }\r
    }\r
  }\r
\r
  //\r
  // The offer with zero "yiaddr" is a proxy offer.\r
  //\r
  if (Offer->Dhcp4.Header.YourAddr.Addr[0] == 0) {\r
    IsProxyOffer = TRUE;\r
  }\r
\r
  //\r
  // The offer with "PXEClient" is a PXE offer.\r
  //\r
  Option = Options[PXEBC_DHCP4_TAG_INDEX_CLASS_ID];\r
  if ((Option != NULL) && (Option->Length >= 9) &&\r
      (CompareMem (Option->Data, DEFAULT_CLASS_ID_DATA, 9) == 0))\r
  {\r
    IsPxeOffer = TRUE;\r
  }\r
\r
  //\r
  // Parse PXE vendor options in this offer, and store the contents/pointers.\r
  //\r
  Option = Options[PXEBC_DHCP4_TAG_INDEX_VENDOR];\r
  if (IsPxeOffer && (Option != NULL)) {\r
    PxeBcParseVendorOptions (Option, &Cache4->VendorOpt);\r
  }\r
\r
  //\r
  // Parse PXE boot file name:\r
  // According to PXE spec, boot file name should be read from DHCP option 67 (bootfile name) if present.\r
  // Otherwise, read from boot file field in DHCP header.\r
  //\r
  if (Options[PXEBC_DHCP4_TAG_INDEX_BOOTFILE] != NULL) {\r
    //\r
    // RFC 2132, Section 9.5 does not strictly state Bootfile name (option 67) is null\r
    // terminated string. So force to append null terminated character at the end of string.\r
    //\r
    Ptr8  =  (UINT8 *)&Options[PXEBC_DHCP4_TAG_INDEX_BOOTFILE]->Data[0];\r
    Ptr8 += Options[PXEBC_DHCP4_TAG_INDEX_BOOTFILE]->Length;\r
    if (*(Ptr8 - 1) != '\0') {\r
      *Ptr8 = '\0';\r
    }\r
  } else if (!FileFieldOverloaded && (Offer->Dhcp4.Header.BootFileName[0] != 0)) {\r
    //\r
    // If the bootfile is not present and bootfilename is present in DHCPv4 packet, just parse it.\r
    // Do not count dhcp option header here, or else will destroy the serverhostname.\r
    //\r
    Options[PXEBC_DHCP4_TAG_INDEX_BOOTFILE] = (EFI_DHCP4_PACKET_OPTION *)\r
                                              (&Offer->Dhcp4.Header.BootFileName[0] -\r
                                               OFFSET_OF (EFI_DHCP4_PACKET_OPTION, Data[0]));\r
  }\r
\r
  //\r
  // Determine offer type of the DHCPv4 packet.\r
  //\r
  Option = Options[PXEBC_DHCP4_TAG_INDEX_MSG_TYPE];\r
  if ((Option == NULL) || (Option->Data[0] == 0)) {\r
    //\r
    // It's a Bootp offer.\r
    //\r
    OfferType = PxeOfferTypeBootp;\r
\r
    Option = Cache4->OptList[PXEBC_DHCP4_TAG_INDEX_BOOTFILE];\r
    if (Option == NULL) {\r
      //\r
      // If the Bootp offer without bootfilename, discard it.\r
      //\r
      return EFI_DEVICE_ERROR;\r
    }\r
  } else {\r
    if (IS_VALID_DISCOVER_VENDOR_OPTION (Cache4->VendorOpt.BitMap)) {\r
      //\r
      // It's a PXE10 offer with PXEClient and discover vendor option.\r
      //\r
      OfferType = IsProxyOffer ? PxeOfferTypeProxyPxe10 : PxeOfferTypeDhcpPxe10;\r
    } else if (IS_VALID_MTFTP_VENDOR_OPTION (Cache4->VendorOpt.BitMap)) {\r
      //\r
      // It's a WFM11a offer with PXEClient and mtftp vendor option.\r
      // But multi-cast download is not supported currently, so discard it.\r
      //\r
      return EFI_DEVICE_ERROR;\r
    } else if (IsPxeOffer) {\r
      //\r
      // It's a BINL offer only with PXEClient.\r
      //\r
      OfferType = IsProxyOffer ? PxeOfferTypeProxyBinl : PxeOfferTypeDhcpBinl;\r
    } else {\r
      //\r
      // It's a DHCPv4 only offer, which is a pure DHCPv4 offer packet.\r
      //\r
      OfferType = PxeOfferTypeDhcpOnly;\r
    }\r
  }\r
\r
  Cache4->OfferType = OfferType;\r
\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  Cache the DHCPv4 ack packet, and parse it on demand.\r
\r
  @param[in]  Private             Pointer to PxeBc private data.\r
  @param[in]  Ack                 Pointer to the DHCPv4 ack packet.\r
  @param[in]  Verified            If TRUE, parse the ACK packet and store info into mode data.\r
\r
  @retval     EFI_SUCCESS                Cache and parse the packet successfully.\r
  @retval     EFI_BUFFER_TOO_SMALL       Cache buffer is not big enough to hold the packet.\r
\r
**/\r
EFI_STATUS\r
PxeBcCopyDhcp4Ack (\r
  IN PXEBC_PRIVATE_DATA  *Private,\r
  IN EFI_DHCP4_PACKET    *Ack,\r
  IN BOOLEAN             Verified\r
  )\r
{\r
  EFI_PXE_BASE_CODE_MODE  *Mode;\r
  EFI_STATUS              Status;\r
\r
  Mode = Private->PxeBc.Mode;\r
\r
  Status = PxeBcCacheDhcp4Packet (&Private->DhcpAck.Dhcp4.Packet.Ack, Ack);\r
  if (EFI_ERROR (Status)) {\r
    return Status;\r
  }\r
\r
  if (Verified) {\r
    //\r
    // Parse the ack packet and store it into mode data if needed.\r
    //\r
    PxeBcParseDhcp4Packet (&Private->DhcpAck.Dhcp4);\r
    CopyMem (&Mode->DhcpAck.Dhcpv4, &Ack->Dhcp4, Ack->Length);\r
    Mode->DhcpAckReceived = TRUE;\r
  }\r
\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  Cache the DHCPv4 proxy offer packet according to the received order.\r
\r
  @param[in]  Private               Pointer to PxeBc private data.\r
  @param[in]  OfferIndex            The received order of offer packets.\r
\r
  @retval     EFI_SUCCESS                Cache and parse the packet successfully.\r
  @retval     EFI_BUFFER_TOO_SMALL       Cache buffer is not big enough to hold the packet.\r
\r
**/\r
EFI_STATUS\r
PxeBcCopyProxyOffer (\r
  IN PXEBC_PRIVATE_DATA  *Private,\r
  IN UINT32              OfferIndex\r
  )\r
{\r
  EFI_PXE_BASE_CODE_MODE  *Mode;\r
  EFI_DHCP4_PACKET        *Offer;\r
  EFI_STATUS              Status;\r
\r
  ASSERT (OfferIndex < Private->OfferNum);\r
  ASSERT (OfferIndex < PXEBC_OFFER_MAX_NUM);\r
\r
  Mode  = Private->PxeBc.Mode;\r
  Offer = &Private->OfferBuffer[OfferIndex].Dhcp4.Packet.Offer;\r
\r
  //\r
  // Cache the proxy offer packet and parse it.\r
  //\r
  Status = PxeBcCacheDhcp4Packet (&Private->ProxyOffer.Dhcp4.Packet.Offer, Offer);\r
  if (EFI_ERROR (Status)) {\r
    return Status;\r
  }\r
\r
  PxeBcParseDhcp4Packet (&Private->ProxyOffer.Dhcp4);\r
\r
  //\r
  // Store this packet into mode data.\r
  //\r
  CopyMem (&Mode->ProxyOffer.Dhcpv4, &Offer->Dhcp4, Offer->Length);\r
  Mode->ProxyOfferReceived = TRUE;\r
\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  Retry to request bootfile name by the BINL offer.\r
\r
  @param[in]  Private              Pointer to PxeBc private data.\r
  @param[in]  Index                The received order of offer packets.\r
\r
  @retval     EFI_SUCCESS          Successfully retried to request bootfile name.\r
  @retval     EFI_DEVICE_ERROR     Failed to retry bootfile name.\r
\r
**/\r
EFI_STATUS\r
PxeBcRetryBinlOffer (\r
  IN PXEBC_PRIVATE_DATA  *Private,\r
  IN UINT32              Index\r
  )\r
{\r
  EFI_DHCP4_PACKET          *Offer;\r
  EFI_IP_ADDRESS            ServerIp;\r
  EFI_STATUS                Status;\r
  PXEBC_DHCP4_PACKET_CACHE  *Cache4;\r
  EFI_DHCP4_PACKET          *Reply;\r
\r
  ASSERT (Index < PXEBC_OFFER_MAX_NUM);\r
  ASSERT (\r
    Private->OfferBuffer[Index].Dhcp4.OfferType == PxeOfferTypeDhcpBinl ||\r
    Private->OfferBuffer[Index].Dhcp4.OfferType == PxeOfferTypeProxyBinl\r
    );\r
\r
  Offer = &Private->OfferBuffer[Index].Dhcp4.Packet.Offer;\r
\r
  //\r
  // Prefer to siaddr in header as next server address. If it's zero, then use option 54.\r
  //\r
  if (Offer->Dhcp4.Header.ServerAddr.Addr[0] == 0) {\r
    CopyMem (\r
      &ServerIp.Addr[0],\r
      Private->OfferBuffer[Index].Dhcp4.OptList[PXEBC_DHCP4_TAG_INDEX_SERVER_ID]->Data,\r
      sizeof (EFI_IPv4_ADDRESS)\r
      );\r
  } else {\r
    CopyMem (\r
      &ServerIp.Addr[0],\r
      &Offer->Dhcp4.Header.ServerAddr,\r
      sizeof (EFI_IPv4_ADDRESS)\r
      );\r
  }\r
\r
  Private->IsDoDiscover = FALSE;\r
  Cache4                = &Private->ProxyOffer.Dhcp4;\r
  Reply                 = &Cache4->Packet.Offer;\r
\r
  //\r
  // Send another request packet for bootfile name.\r
  //\r
  Status = PxeBcDhcp4Discover (\r
             Private,\r
             0,\r
             NULL,\r
             FALSE,\r
             &ServerIp,\r
             0,\r
             NULL\r
             );\r
  if (EFI_ERROR (Status)) {\r
    return Status;\r
  }\r
\r
  //\r
  // Parse the reply for the last request packet.\r
  //\r
  Status = PxeBcParseDhcp4Packet (Cache4);\r
  if (EFI_ERROR (Status)) {\r
    return Status;\r
  }\r
\r
  if ((Cache4->OfferType != PxeOfferTypeProxyPxe10) &&\r
      (Cache4->OfferType != PxeOfferTypeProxyWfm11a) &&\r
      (Cache4->OptList[PXEBC_DHCP4_TAG_INDEX_BOOTFILE] == NULL))\r
  {\r
    //\r
    // This BINL ack doesn't have discovery option set or multicast option set\r
    // or bootfile name specified.\r
    //\r
    return EFI_DEVICE_ERROR;\r
  }\r
\r
  //\r
  // Store the reply into mode data.\r
  //\r
  Private->PxeBc.Mode->ProxyOfferReceived = TRUE;\r
  CopyMem (&Private->PxeBc.Mode->ProxyOffer.Dhcpv4, &Reply->Dhcp4, Reply->Length);\r
\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  Cache all the received DHCPv4 offers, and set OfferIndex and OfferCount.\r
\r
  @param[in]  Private               Pointer to PxeBc private data.\r
  @param[in]  RcvdOffer             Pointer to the received offer packet.\r
\r
  @retval     EFI_SUCCESS      Cache and parse the packet successfully.\r
  @retval     Others           Operation failed.\r
\r
**/\r
EFI_STATUS\r
PxeBcCacheDhcp4Offer (\r
  IN PXEBC_PRIVATE_DATA  *Private,\r
  IN EFI_DHCP4_PACKET    *RcvdOffer\r
  )\r
{\r
  PXEBC_DHCP4_PACKET_CACHE  *Cache4;\r
  EFI_DHCP4_PACKET          *Offer;\r
  PXEBC_OFFER_TYPE          OfferType;\r
  EFI_STATUS                Status;\r
\r
  ASSERT (Private->OfferNum < PXEBC_OFFER_MAX_NUM);\r
  Cache4 = &Private->OfferBuffer[Private->OfferNum].Dhcp4;\r
  Offer  = &Cache4->Packet.Offer;\r
\r
  //\r
  // Cache the content of DHCPv4 packet firstly.\r
  //\r
  Status = PxeBcCacheDhcp4Packet (Offer, RcvdOffer);\r
  if (EFI_ERROR (Status)) {\r
    return Status;\r
  }\r
\r
  //\r
  // Validate the DHCPv4 packet, and parse the options and offer type.\r
  //\r
  if (EFI_ERROR (PxeBcParseDhcp4Packet (Cache4))) {\r
    return EFI_ABORTED;\r
  }\r
\r
  //\r
  // Determine whether cache the current offer by type, and record OfferIndex and OfferCount.\r
  //\r
  OfferType = Cache4->OfferType;\r
  ASSERT (OfferType < PxeOfferTypeMax);\r
\r
  if (OfferType == PxeOfferTypeBootp) {\r
    //\r
    // It's a Bootp offer, only cache the first one, and discard the others.\r
    //\r
    if (Private->OfferCount[OfferType] == 0) {\r
      Private->OfferIndex[OfferType][0] = Private->OfferNum;\r
      Private->OfferCount[OfferType]    = 1;\r
    } else {\r
      return EFI_ABORTED;\r
    }\r
  } else {\r
    ASSERT (Private->OfferCount[OfferType] < PXEBC_OFFER_MAX_NUM);\r
    if (IS_PROXY_DHCP_OFFER (Offer)) {\r
      //\r
      // It's a proxy offer without yiaddr, including PXE10, WFM11a or BINL offer.\r
      //\r
      Private->IsProxyRecved = TRUE;\r
\r
      if (OfferType == PxeOfferTypeProxyBinl) {\r
        //\r
        // Cache all proxy BINL offers.\r
        //\r
        Private->OfferIndex[OfferType][Private->OfferCount[OfferType]] = Private->OfferNum;\r
        Private->OfferCount[OfferType]++;\r
      } else if (((OfferType == PxeOfferTypeProxyPxe10) || (OfferType == PxeOfferTypeProxyWfm11a)) &&\r
                 (Private->OfferCount[OfferType] < 1))\r
      {\r
        //\r
        // Only cache the first PXE10/WFM11a offer, and discard the others.\r
        //\r
        Private->OfferIndex[OfferType][0] = Private->OfferNum;\r
        Private->OfferCount[OfferType]    = 1;\r
      } else {\r
        return EFI_ABORTED;\r
      }\r
    } else {\r
      //\r
      // It's a DHCPv4 offer with yiaddr, and cache them all.\r
      //\r
      Private->OfferIndex[OfferType][Private->OfferCount[OfferType]] = Private->OfferNum;\r
      Private->OfferCount[OfferType]++;\r
    }\r
  }\r
\r
  Private->OfferNum++;\r
\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  Select an DHCPv4 offer, and record SelectIndex and SelectProxyType.\r
\r
  @param[in]  Private             Pointer to PxeBc private data.\r
\r
**/\r
VOID\r
PxeBcSelectDhcp4Offer (\r
  IN PXEBC_PRIVATE_DATA  *Private\r
  )\r
{\r
  UINT32            Index;\r
  UINT32            OfferIndex;\r
  EFI_DHCP4_PACKET  *Offer;\r
\r
  Private->SelectIndex = 0;\r
\r
  if (Private->IsOfferSorted) {\r
    //\r
    // Select offer by default policy.\r
    //\r
    if (Private->OfferCount[PxeOfferTypeDhcpPxe10] > 0) {\r
      //\r
      // 1. DhcpPxe10 offer\r
      //\r
      Private->SelectIndex = Private->OfferIndex[PxeOfferTypeDhcpPxe10][0] + 1;\r
    } else if (Private->OfferCount[PxeOfferTypeDhcpWfm11a] > 0) {\r
      //\r
      // 2. DhcpWfm11a offer\r
      //\r
      Private->SelectIndex = Private->OfferIndex[PxeOfferTypeDhcpWfm11a][0] + 1;\r
    } else if ((Private->OfferCount[PxeOfferTypeDhcpOnly] > 0) &&\r
               (Private->OfferCount[PxeOfferTypeProxyPxe10] > 0))\r
    {\r
      //\r
      // 3. DhcpOnly offer and ProxyPxe10 offer.\r
      //\r
      Private->SelectIndex     = Private->OfferIndex[PxeOfferTypeDhcpOnly][0] + 1;\r
      Private->SelectProxyType = PxeOfferTypeProxyPxe10;\r
    } else if ((Private->OfferCount[PxeOfferTypeDhcpOnly] > 0) &&\r
               (Private->OfferCount[PxeOfferTypeProxyWfm11a] > 0))\r
    {\r
      //\r
      // 4. DhcpOnly offer and ProxyWfm11a offer.\r
      //\r
      Private->SelectIndex     = Private->OfferIndex[PxeOfferTypeDhcpOnly][0] + 1;\r
      Private->SelectProxyType = PxeOfferTypeProxyWfm11a;\r
    } else if (Private->OfferCount[PxeOfferTypeDhcpBinl] > 0) {\r
      //\r
      // 5. DhcpBinl offer.\r
      //\r
      Private->SelectIndex = Private->OfferIndex[PxeOfferTypeDhcpBinl][0] + 1;\r
    } else if ((Private->OfferCount[PxeOfferTypeDhcpOnly] > 0) &&\r
               (Private->OfferCount[PxeOfferTypeProxyBinl] > 0))\r
    {\r
      //\r
      // 6. DhcpOnly offer and ProxyBinl offer.\r
      //\r
      Private->SelectIndex     = Private->OfferIndex[PxeOfferTypeDhcpOnly][0] + 1;\r
      Private->SelectProxyType = PxeOfferTypeProxyBinl;\r
    } else {\r
      //\r
      // 7. DhcpOnly offer with bootfilename.\r
      //\r
      for (Index = 0; Index < Private->OfferCount[PxeOfferTypeDhcpOnly]; Index++) {\r
        OfferIndex = Private->OfferIndex[PxeOfferTypeDhcpOnly][Index];\r
        if (Private->OfferBuffer[OfferIndex].Dhcp4.OptList[PXEBC_DHCP4_TAG_INDEX_BOOTFILE] != NULL) {\r
          Private->SelectIndex = OfferIndex + 1;\r
          break;\r
        }\r
      }\r
\r
      //\r
      // 8. Bootp offer with bootfilename.\r
      //\r
      OfferIndex = Private->OfferIndex[PxeOfferTypeBootp][0];\r
      if ((Private->SelectIndex == 0) &&\r
          (Private->OfferCount[PxeOfferTypeBootp] > 0) &&\r
          (Private->OfferBuffer[OfferIndex].Dhcp4.OptList[PXEBC_DHCP4_TAG_INDEX_BOOTFILE] != NULL))\r
      {\r
        Private->SelectIndex = OfferIndex + 1;\r
      }\r
    }\r
  } else {\r
    //\r
    // Select offer by received order.\r
    //\r
    for (Index = 0; Index < Private->OfferNum; Index++) {\r
      Offer = &Private->OfferBuffer[Index].Dhcp4.Packet.Offer;\r
\r
      if (IS_PROXY_DHCP_OFFER (Offer)) {\r
        //\r
        // Skip proxy offers\r
        //\r
        continue;\r
      }\r
\r
      if (!Private->IsProxyRecved &&\r
          (Private->OfferBuffer[Index].Dhcp4.OfferType == PxeOfferTypeDhcpOnly) &&\r
          (Private->OfferBuffer[Index].Dhcp4.OptList[PXEBC_DHCP4_TAG_INDEX_BOOTFILE] == NULL))\r
      {\r
        //\r
        // Skip if DhcpOnly offer without any other proxy offers or bootfilename.\r
        //\r
        continue;\r
      }\r
\r
      //\r
      // Record the index of the select offer.\r
      //\r
      Private->SelectIndex = Index + 1;\r
      break;\r
    }\r
  }\r
}\r
\r
/**\r
  Handle the DHCPv4 offer packet.\r
\r
  @param[in]  Private               Pointer to PxeBc private data.\r
\r
  @retval     EFI_SUCCESS           Handled the DHCPv4 offer packet successfully.\r
  @retval     EFI_NO_RESPONSE       No response to the following request packet.\r
  @retval     EFI_NOT_FOUND         No boot filename received.\r
  @retval     EFI_BUFFER_TOO_SMALL  Can't cache the offer pacet.\r
\r
**/\r
EFI_STATUS\r
PxeBcHandleDhcp4Offer (\r
  IN PXEBC_PRIVATE_DATA  *Private\r
  )\r
{\r
  PXEBC_DHCP4_PACKET_CACHE  *Cache4;\r
  EFI_DHCP4_PACKET_OPTION   **Options;\r
  UINT32                    Index;\r
  EFI_DHCP4_PACKET          *Offer;\r
  PXEBC_OFFER_TYPE          OfferType;\r
  UINT32                    ProxyIndex;\r
  UINT32                    SelectIndex;\r
  EFI_STATUS                Status;\r
  EFI_PXE_BASE_CODE_MODE    *Mode;\r
  EFI_DHCP4_PACKET          *Ack;\r
\r
  ASSERT (Private->SelectIndex > 0);\r
  SelectIndex = (UINT32)(Private->SelectIndex - 1);\r
  ASSERT (SelectIndex < PXEBC_OFFER_MAX_NUM);\r
  Cache4  = &Private->OfferBuffer[SelectIndex].Dhcp4;\r
  Options = Cache4->OptList;\r
  Status  = EFI_SUCCESS;\r
\r
  if (Cache4->OfferType == PxeOfferTypeDhcpBinl) {\r
    //\r
    // DhcpBinl offer is selected, so need try to request bootfilename by this offer.\r
    //\r
    if (EFI_ERROR (PxeBcRetryBinlOffer (Private, SelectIndex))) {\r
      Status = EFI_NO_RESPONSE;\r
    }\r
  } else if (Cache4->OfferType == PxeOfferTypeDhcpOnly) {\r
    if (Private->IsProxyRecved) {\r
      //\r
      // DhcpOnly offer is selected, so need try to request bootfile name.\r
      //\r
      ProxyIndex = 0;\r
      if (Private->IsOfferSorted) {\r
        //\r
        // The proxy offer should be determined if select by default policy.\r
        // IsOfferSorted means all offers are labeled by OfferIndex.\r
        //\r
        ASSERT (Private->SelectProxyType < PxeOfferTypeMax);\r
        ASSERT (Private->OfferCount[Private->SelectProxyType] > 0);\r
\r
        if (Private->SelectProxyType == PxeOfferTypeProxyBinl) {\r
          //\r
          // Try all the cached ProxyBinl offer one by one to request bootfile name.\r
          //\r
          for (Index = 0; Index < Private->OfferCount[Private->SelectProxyType]; Index++) {\r
            ASSERT (Index < PXEBC_OFFER_MAX_NUM);\r
            ProxyIndex = Private->OfferIndex[Private->SelectProxyType][Index];\r
            if (!EFI_ERROR (PxeBcRetryBinlOffer (Private, ProxyIndex))) {\r
              break;\r
            }\r
          }\r
\r
          if (Index == Private->OfferCount[Private->SelectProxyType]) {\r
            Status = EFI_NO_RESPONSE;\r
          }\r
        } else {\r
          //\r
          // For other proxy offers, only one is buffered.\r
          //\r
          ProxyIndex = Private->OfferIndex[Private->SelectProxyType][0];\r
        }\r
      } else {\r
        //\r
        // The proxy offer should not be determined if select by received order.\r
        //\r
        Status = EFI_NO_RESPONSE;\r
\r
        for (Index = 0; Index < Private->OfferNum; Index++) {\r
          ASSERT (Index < PXEBC_OFFER_MAX_NUM);\r
          Offer     = &Private->OfferBuffer[Index].Dhcp4.Packet.Offer;\r
          OfferType = Private->OfferBuffer[Index].Dhcp4.OfferType;\r
          if (!IS_PROXY_DHCP_OFFER (Offer)) {\r
            //\r
            // Skip non proxy DHCPv4 offers.\r
            //\r
            continue;\r
          }\r
\r
          if (OfferType == PxeOfferTypeProxyBinl) {\r
            //\r
            // Try all the cached ProxyBinl offer one by one to request bootfile name.\r
            //\r
            if (EFI_ERROR (PxeBcRetryBinlOffer (Private, Index))) {\r
              continue;\r
            }\r
          }\r
\r
          Private->SelectProxyType = OfferType;\r
          ProxyIndex               = Index;\r
          Status                   = EFI_SUCCESS;\r
          break;\r
        }\r
      }\r
\r
      if (!EFI_ERROR (Status) && (Private->SelectProxyType != PxeOfferTypeProxyBinl)) {\r
        //\r
        // Success to try to request by a ProxyPxe10 or ProxyWfm11a offer, copy and parse it.\r
        //\r
        Status = PxeBcCopyProxyOffer (Private, ProxyIndex);\r
      }\r
    } else {\r
      //\r
      //  Otherwise, the bootfile name must be included in DhcpOnly offer.\r
      //\r
      if (Options[PXEBC_DHCP4_TAG_INDEX_BOOTFILE] == NULL) {\r
        Status = EFI_NOT_FOUND;\r
      }\r
    }\r
  }\r
\r
  if (!EFI_ERROR (Status)) {\r
    //\r
    // All PXE boot information is ready by now.\r
    //\r
    Mode  = Private->PxeBc.Mode;\r
    Offer = &Cache4->Packet.Offer;\r
    Ack   = &Private->DhcpAck.Dhcp4.Packet.Ack;\r
    if (Cache4->OfferType == PxeOfferTypeBootp) {\r
      //\r
      // Bootp is a special case that only 2 packets involved instead of 4. So the bootp's reply\r
      // should be taken as ack.\r
      //\r
      Ack = Offer;\r
    }\r
\r
    Status = PxeBcCopyDhcp4Ack (Private, Ack, TRUE);\r
    if (EFI_ERROR (Status)) {\r
      return Status;\r
    }\r
\r
    Mode->DhcpDiscoverValid = TRUE;\r
  }\r
\r
  return Status;\r
}\r
\r
/**\r
  EFI_DHCP4_CALLBACK is provided by the consumer of the EFI DHCPv4 Protocol driver\r
  to intercept events that occurred in the configuration process.\r
\r
  @param[in]  This              Pointer to the EFI DHCPv4 Protocol.\r
  @param[in]  Context           Pointer to the context set by EFI_DHCP4_PROTOCOL.Configure().\r
  @param[in]  CurrentState      The current operational state of the EFI DHCPv4 Protocol driver.\r
  @param[in]  Dhcp4Event        The event that occurs in the current state, which usually means a\r
                                state transition.\r
  @param[in]  Packet            The DHCPv4 packet that is going to be sent or already received.\r
  @param[out] NewPacket         The packet that is used to replace the above Packet.\r
\r
  @retval EFI_SUCCESS           Tells the EFI DHCPv4 Protocol driver to continue the DHCP process.\r
  @retval EFI_NOT_READY         Only used in the Dhcp4Selecting state. The EFI DHCPv4 Protocol\r
                                driver will continue to wait for more DHCPOFFER packets until the\r
                                retry timeout expires.\r
  @retval EFI_ABORTED           Tells the EFI DHCPv4 Protocol driver to abort the current process\r
                                and return to the Dhcp4Init or Dhcp4InitReboot state.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
PxeBcDhcp4CallBack (\r
  IN  EFI_DHCP4_PROTOCOL  *This,\r
  IN  VOID                *Context,\r
  IN  EFI_DHCP4_STATE     CurrentState,\r
  IN  EFI_DHCP4_EVENT     Dhcp4Event,\r
  IN  EFI_DHCP4_PACKET    *Packet            OPTIONAL,\r
  OUT EFI_DHCP4_PACKET    **NewPacket        OPTIONAL\r
  )\r
{\r
  PXEBC_PRIVATE_DATA                   *Private;\r
  EFI_PXE_BASE_CODE_MODE               *Mode;\r
  EFI_PXE_BASE_CODE_CALLBACK_PROTOCOL  *Callback;\r
  EFI_DHCP4_PACKET_OPTION              *MaxMsgSize;\r
  UINT16                               Value;\r
  EFI_STATUS                           Status;\r
  BOOLEAN                              Received;\r
\r
  if ((Dhcp4Event != Dhcp4RcvdOffer) &&\r
      (Dhcp4Event != Dhcp4SelectOffer) &&\r
      (Dhcp4Event != Dhcp4SendDiscover) &&\r
      (Dhcp4Event != Dhcp4RcvdAck))\r
  {\r
    return EFI_SUCCESS;\r
  }\r
\r
  ASSERT (Packet != NULL);\r
\r
  Private  = (PXEBC_PRIVATE_DATA *)Context;\r
  Mode     = Private->PxeBc.Mode;\r
  Callback = Private->PxeBcCallback;\r
\r
  //\r
  // Override the Maximum DHCP Message Size.\r
  //\r
  MaxMsgSize = PxeBcParseDhcp4Options (\r
                 Packet->Dhcp4.Option,\r
                 GET_OPTION_BUFFER_LEN (Packet),\r
                 DHCP4_TAG_MAXMSG\r
                 );\r
  if (MaxMsgSize != NULL) {\r
    Value = HTONS (PXEBC_DHCP4_PACKET_MAX_SIZE);\r
    CopyMem (MaxMsgSize->Data, &Value, sizeof (Value));\r
  }\r
\r
  //\r
  // Callback to user if any packets sent or received.\r
  //\r
  if ((Dhcp4Event != Dhcp4SelectOffer) && (Callback != NULL)) {\r
    Received = (BOOLEAN)(Dhcp4Event == Dhcp4RcvdOffer || Dhcp4Event == Dhcp4RcvdAck);\r
    Status   = Callback->Callback (\r
                           Callback,\r
                           Private->Function,\r
                           Received,\r
                           Packet->Length,\r
                           (EFI_PXE_BASE_CODE_PACKET *)&Packet->Dhcp4\r
                           );\r
    if (Status != EFI_PXE_BASE_CODE_CALLBACK_STATUS_CONTINUE) {\r
      return EFI_ABORTED;\r
    }\r
  }\r
\r
  Status = EFI_SUCCESS;\r
\r
  switch (Dhcp4Event) {\r
    case Dhcp4SendDiscover:\r
      if (Packet->Length > PXEBC_DHCP4_PACKET_MAX_SIZE) {\r
        //\r
        // If the to be sent packet exceeds the maximum length, abort the DHCP process.\r
        //\r
        Status = EFI_ABORTED;\r
        break;\r
      }\r
\r
      //\r
      // Cache the DHCPv4 discover packet to mode data directly.\r
      // It need to check SendGuid as well as Dhcp4SendRequest.\r
      //\r
      CopyMem (&Mode->DhcpDiscover.Dhcpv4, &Packet->Dhcp4, Packet->Length);\r
\r
    case Dhcp4SendRequest:\r
      if (Packet->Length > PXEBC_DHCP4_PACKET_MAX_SIZE) {\r
        //\r
        // If the to be sent packet exceeds the maximum length, abort the DHCP process.\r
        //\r
        Status = EFI_ABORTED;\r
        break;\r
      }\r
\r
      if (Mode->SendGUID) {\r
        //\r
        // Send the system Guid instead of the MAC address as the hardware address if required.\r
        //\r
        if (EFI_ERROR (NetLibGetSystemGuid ((EFI_GUID *)Packet->Dhcp4.Header.ClientHwAddr))) {\r
          //\r
          // Zero the Guid to indicate NOT programmable if failed to get system Guid.\r
          //\r
          DEBUG ((DEBUG_WARN, "PXE: Failed to read system GUID from the smbios table!\n"));\r
          ZeroMem (Packet->Dhcp4.Header.ClientHwAddr, sizeof (EFI_GUID));\r
        }\r
\r
        Packet->Dhcp4.Header.HwAddrLen = (UINT8)sizeof (EFI_GUID);\r
      }\r
\r
      break;\r
\r
    case Dhcp4RcvdOffer:\r
      Status = EFI_NOT_READY;\r
      if (Packet->Length > PXEBC_DHCP4_PACKET_MAX_SIZE) {\r
        //\r
        // Ignore the incoming packets which exceed the maximum length.\r
        //\r
        break;\r
      }\r
\r
      if (Private->OfferNum < PXEBC_OFFER_MAX_NUM) {\r
        //\r
        // Cache the DHCPv4 offers to OfferBuffer[] for select later, and record\r
        // the OfferIndex and OfferCount.\r
        // If error happens, just ignore this packet and continue to wait more offer.\r
        //\r
        PxeBcCacheDhcp4Offer (Private, Packet);\r
      }\r
\r
      break;\r
\r
    case Dhcp4SelectOffer:\r
      ASSERT (NewPacket != NULL);\r
\r
      //\r
      // Select offer by the default policy or by order, and record the SelectIndex\r
      // and SelectProxyType.\r
      //\r
      PxeBcSelectDhcp4Offer (Private);\r
\r
      if (Private->SelectIndex == 0) {\r
        Status = EFI_ABORTED;\r
      } else {\r
        *NewPacket = &Private->OfferBuffer[Private->SelectIndex - 1].Dhcp4.Packet.Offer;\r
      }\r
\r
      break;\r
\r
    case Dhcp4RcvdAck:\r
      //\r
      // Cache the DHCPv4 ack to Private->Dhcp4Ack, but it's not the final ack in mode data\r
      // without verification.\r
      //\r
      ASSERT (Private->SelectIndex != 0);\r
\r
      Status = PxeBcCopyDhcp4Ack (Private, Packet, FALSE);\r
      if (EFI_ERROR (Status)) {\r
        Status = EFI_ABORTED;\r
      }\r
\r
      break;\r
\r
    default:\r
      break;\r
  }\r
\r
  return Status;\r
}\r
\r
/**\r
  Build and send out the request packet for the bootfile, and parse the reply.\r
\r
  @param[in]  Private               Pointer to PxeBc private data.\r
  @param[in]  Type                  PxeBc option boot item type.\r
  @param[in]  Layer                 Pointer to option boot item layer.\r
  @param[in]  UseBis                Use BIS or not.\r
  @param[in]  DestIp                Pointer to the server address.\r
  @param[in]  IpCount               The total count of the server address.\r
  @param[in]  SrvList               Pointer to EFI_PXE_BASE_CODE_SRVLIST.\r
\r
  @retval     EFI_SUCCESS           Successfully discovered boot file.\r
  @retval     EFI_OUT_OF_RESOURCES  Failed to allocate resource.\r
  @retval     EFI_NOT_FOUND         Can't get the PXE reply packet.\r
  @retval     Others                Failed to discover boot file.\r
\r
**/\r
EFI_STATUS\r
PxeBcDhcp4Discover (\r
  IN  PXEBC_PRIVATE_DATA         *Private,\r
  IN  UINT16                     Type,\r
  IN  UINT16                     *Layer,\r
  IN  BOOLEAN                    UseBis,\r
  IN  EFI_IP_ADDRESS             *DestIp,\r
  IN  UINT16                     IpCount,\r
  IN  EFI_PXE_BASE_CODE_SRVLIST  *SrvList\r
  )\r
{\r
  EFI_PXE_BASE_CODE_UDP_PORT        Sport;\r
  EFI_PXE_BASE_CODE_MODE            *Mode;\r
  EFI_DHCP4_PROTOCOL                *Dhcp4;\r
  EFI_DHCP4_TRANSMIT_RECEIVE_TOKEN  Token;\r
  BOOLEAN                           IsBCast;\r
  EFI_STATUS                        Status;\r
  UINT16                            RepIndex;\r
  UINT16                            SrvIndex;\r
  UINT16                            TryIndex;\r
  EFI_DHCP4_LISTEN_POINT            ListenPoint;\r
  EFI_DHCP4_PACKET                  *Response;\r
  UINT8                             Buffer[PXEBC_DHCP4_OPTION_MAX_SIZE];\r
  EFI_DHCP4_PACKET_OPTION           *OptList[PXEBC_DHCP4_OPTION_MAX_NUM];\r
  UINT32                            OptCount;\r
  EFI_DHCP4_PACKET_OPTION           *PxeOpt;\r
  PXEBC_OPTION_BOOT_ITEM            *PxeBootItem;\r
  UINT8                             VendorOptLen;\r
  UINT32                            Xid;\r
\r
  Mode   = Private->PxeBc.Mode;\r
  Dhcp4  = Private->Dhcp4;\r
  Status = EFI_SUCCESS;\r
\r
  ZeroMem (&Token, sizeof (EFI_DHCP4_TRANSMIT_RECEIVE_TOKEN));\r
\r
  //\r
  // Use broadcast if destination address not specified.\r
  //\r
  if (DestIp == NULL) {\r
    Sport   = PXEBC_DHCP4_S_PORT;\r
    IsBCast = TRUE;\r
  } else {\r
    Sport   = PXEBC_BS_DISCOVER_PORT;\r
    IsBCast = FALSE;\r
  }\r
\r
  if (!UseBis && (Layer != NULL)) {\r
    *Layer &= EFI_PXE_BASE_CODE_BOOT_LAYER_MASK;\r
  }\r
\r
  //\r
  // Build all the options for the request packet.\r
  //\r
  OptCount = PxeBcBuildDhcp4Options (Private, OptList, Buffer, TRUE);\r
\r
  if (Private->IsDoDiscover) {\r
    //\r
    // Add vendor option of PXE_BOOT_ITEM\r
    //\r
    VendorOptLen      = (UINT8)((sizeof (EFI_DHCP4_PACKET_OPTION) - 1) * 2 + sizeof (PXEBC_OPTION_BOOT_ITEM) + 1);\r
    OptList[OptCount] = AllocateZeroPool (VendorOptLen);\r
    if (OptList[OptCount] == NULL) {\r
      return EFI_OUT_OF_RESOURCES;\r
    }\r
\r
    OptList[OptCount]->OpCode    = DHCP4_TAG_VENDOR;\r
    OptList[OptCount]->Length    = (UINT8)(VendorOptLen - 2);\r
    PxeOpt                       = (EFI_DHCP4_PACKET_OPTION *)OptList[OptCount]->Data;\r
    PxeOpt->OpCode               = PXEBC_VENDOR_TAG_BOOT_ITEM;\r
    PxeOpt->Length               = (UINT8)sizeof (PXEBC_OPTION_BOOT_ITEM);\r
    PxeBootItem                  = (PXEBC_OPTION_BOOT_ITEM *)PxeOpt->Data;\r
    PxeBootItem->Type            = HTONS (Type);\r
    PxeOpt->Data[PxeOpt->Length] = DHCP4_TAG_EOP;\r
\r
    if (Layer != NULL) {\r
      PxeBootItem->Layer = HTONS (*Layer);\r
    }\r
\r
    OptCount++;\r
  }\r
\r
  //\r
  // Build the request packet with seed packet and option list.\r
  //\r
  Status = Dhcp4->Build (\r
                    Dhcp4,\r
                    &Private->SeedPacket,\r
                    0,\r
                    NULL,\r
                    OptCount,\r
                    OptList,\r
                    &Token.Packet\r
                    );\r
  //\r
  // Free the vendor option of PXE_BOOT_ITEM.\r
  //\r
  if (Private->IsDoDiscover) {\r
    FreePool (OptList[OptCount - 1]);\r
  }\r
\r
  if (EFI_ERROR (Status)) {\r
    return Status;\r
  }\r
\r
  if (Mode->SendGUID) {\r
    if (EFI_ERROR (NetLibGetSystemGuid ((EFI_GUID *)Token.Packet->Dhcp4.Header.ClientHwAddr))) {\r
      //\r
      // Zero the Guid to indicate NOT programmable if failed to get system Guid.\r
      //\r
      DEBUG ((DEBUG_WARN, "PXE: Failed to read system GUID from the smbios table!\n"));\r
      ZeroMem (Token.Packet->Dhcp4.Header.ClientHwAddr, sizeof (EFI_GUID));\r
    }\r
\r
    Token.Packet->Dhcp4.Header.HwAddrLen = (UINT8)sizeof (EFI_GUID);\r
  }\r
\r
  //\r
  // Set fields of the token for the request packet.\r
  //\r
  Xid                                 = NET_RANDOM (NetRandomInitSeed ());\r
  Token.Packet->Dhcp4.Header.Xid      = HTONL (Xid);\r
  Token.Packet->Dhcp4.Header.Reserved = HTONS ((UINT16)((IsBCast) ? 0x8000 : 0x0));\r
  CopyMem (&Token.Packet->Dhcp4.Header.ClientAddr, &Private->StationIp, sizeof (EFI_IPv4_ADDRESS));\r
\r
  Token.RemotePort = Sport;\r
\r
  if (IsBCast) {\r
    SetMem (&Token.RemoteAddress, sizeof (EFI_IPv4_ADDRESS), 0xff);\r
  } else {\r
    CopyMem (&Token.RemoteAddress, DestIp, sizeof (EFI_IPv4_ADDRESS));\r
  }\r
\r
  CopyMem (&Token.GatewayAddress, &Private->GatewayIp, sizeof (EFI_IPv4_ADDRESS));\r
\r
  if (!IsBCast) {\r
    Token.ListenPointCount           = 1;\r
    Token.ListenPoints               = &ListenPoint;\r
    Token.ListenPoints[0].ListenPort = PXEBC_BS_DISCOVER_PORT;\r
    CopyMem (&Token.ListenPoints[0].ListenAddress, &Private->StationIp, sizeof (EFI_IPv4_ADDRESS));\r
    CopyMem (&Token.ListenPoints[0].SubnetMask, &Private->SubnetMask, sizeof (EFI_IPv4_ADDRESS));\r
  }\r
\r
  //\r
  // Send out the request packet to discover the bootfile.\r
  //\r
  for (TryIndex = 1; TryIndex <= PXEBC_BOOT_REQUEST_RETRIES; TryIndex++) {\r
    Token.TimeoutValue                 = (UINT16)(PXEBC_BOOT_REQUEST_TIMEOUT * TryIndex);\r
    Token.Packet->Dhcp4.Header.Seconds = (UINT16)(PXEBC_BOOT_REQUEST_TIMEOUT * (TryIndex - 1));\r
\r
    Status = Dhcp4->TransmitReceive (Dhcp4, &Token);\r
    if (Token.Status != EFI_TIMEOUT) {\r
      break;\r
    }\r
  }\r
\r
  if (TryIndex > PXEBC_BOOT_REQUEST_RETRIES) {\r
    //\r
    // No server response our PXE request\r
    //\r
    Status = EFI_TIMEOUT;\r
  }\r
\r
  if (!EFI_ERROR (Status)) {\r
    RepIndex = 0;\r
    SrvIndex = 0;\r
    Response = Token.ResponseList;\r
    //\r
    // Find the right PXE Reply according to server address.\r
    //\r
    while (RepIndex < Token.ResponseCount) {\r
      if (Response->Length > PXEBC_DHCP4_PACKET_MAX_SIZE) {\r
        SrvIndex = 0;\r
        RepIndex++;\r
        Response = (EFI_DHCP4_PACKET *)((UINT8 *)Response + Response->Size);\r
        continue;\r
      }\r
\r
      while (SrvIndex < IpCount) {\r
        if (SrvList[SrvIndex].AcceptAnyResponse) {\r
          break;\r
        }\r
\r
        if ((SrvList[SrvIndex].Type == Type) &&\r
            EFI_IP4_EQUAL (&Response->Dhcp4.Header.ServerAddr, &SrvList[SrvIndex].IpAddr))\r
        {\r
          break;\r
        }\r
\r
        SrvIndex++;\r
      }\r
\r
      if ((IpCount != SrvIndex) || (IpCount == 0)) {\r
        break;\r
      }\r
\r
      SrvIndex = 0;\r
      RepIndex++;\r
      Response = (EFI_DHCP4_PACKET *)((UINT8 *)Response + Response->Size);\r
    }\r
\r
    if (RepIndex < Token.ResponseCount) {\r
      //\r
      // Cache the right PXE reply packet here, set valid flag later.\r
      // Especially for PXE discover packet, store it into mode data here.\r
      //\r
      if (Private->IsDoDiscover) {\r
        Status = PxeBcCacheDhcp4Packet (&Private->PxeReply.Dhcp4.Packet.Ack, Response);\r
        if (EFI_ERROR (Status)) {\r
          goto ON_EXIT;\r
        }\r
\r
        CopyMem (&Mode->PxeDiscover, &Token.Packet->Dhcp4, Token.Packet->Length);\r
      } else {\r
        Status = PxeBcCacheDhcp4Packet (&Private->ProxyOffer.Dhcp4.Packet.Offer, Response);\r
        if (EFI_ERROR (Status)) {\r
          goto ON_EXIT;\r
        }\r
      }\r
    } else {\r
      //\r
      // Not found the right PXE reply packet.\r
      //\r
      Status = EFI_NOT_FOUND;\r
    }\r
  }\r
\r
ON_EXIT:\r
\r
  if (Token.ResponseList != NULL) {\r
    FreePool (Token.ResponseList);\r
  }\r
\r
  if (Token.Packet != NULL) {\r
    FreePool (Token.Packet);\r
  }\r
\r
  return Status;\r
}\r
\r
/**\r
  Switch the Ip4 policy to static.\r
\r
  @param[in]  Private             The pointer to PXEBC_PRIVATE_DATA.\r
\r
  @retval     EFI_SUCCESS         The policy is already configured to static.\r
  @retval     Others              Other error as indicated..\r
\r
**/\r
EFI_STATUS\r
PxeBcSetIp4Policy (\r
  IN PXEBC_PRIVATE_DATA  *Private\r
  )\r
{\r
  EFI_STATUS                Status;\r
  EFI_IP4_CONFIG2_PROTOCOL  *Ip4Config2;\r
  EFI_IP4_CONFIG2_POLICY    Policy;\r
  UINTN                     DataSize;\r
\r
  Ip4Config2 = Private->Ip4Config2;\r
  DataSize   = sizeof (EFI_IP4_CONFIG2_POLICY);\r
  Status     = Ip4Config2->GetData (\r
                             Ip4Config2,\r
                             Ip4Config2DataTypePolicy,\r
                             &DataSize,\r
                             &Policy\r
                             );\r
  if (EFI_ERROR (Status)) {\r
    return Status;\r
  }\r
\r
  if (Policy != Ip4Config2PolicyStatic) {\r
    Policy = Ip4Config2PolicyStatic;\r
    Status = Ip4Config2->SetData (\r
                           Ip4Config2,\r
                           Ip4Config2DataTypePolicy,\r
                           sizeof (EFI_IP4_CONFIG2_POLICY),\r
                           &Policy\r
                           );\r
    if (EFI_ERROR (Status)) {\r
      return Status;\r
    }\r
  }\r
\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  Start the D.O.R.A DHCPv4 process to acquire the IPv4 address and other PXE boot information.\r
\r
  @param[in]  Private           Pointer to PxeBc private data.\r
  @param[in]  Dhcp4             Pointer to the EFI_DHCP4_PROTOCOL\r
\r
  @retval EFI_SUCCESS           The D.O.R.A process successfully finished.\r
  @retval Others                Failed to finish the D.O.R.A process.\r
\r
**/\r
EFI_STATUS\r
PxeBcDhcp4Dora (\r
  IN PXEBC_PRIVATE_DATA  *Private,\r
  IN EFI_DHCP4_PROTOCOL  *Dhcp4\r
  )\r
{\r
  EFI_PXE_BASE_CODE_MODE   *PxeMode;\r
  EFI_DHCP4_CONFIG_DATA    Config;\r
  EFI_DHCP4_MODE_DATA      Mode;\r
  EFI_DHCP4_PACKET_OPTION  *OptList[PXEBC_DHCP4_OPTION_MAX_NUM];\r
  UINT8                    Buffer[PXEBC_DHCP4_OPTION_MAX_SIZE];\r
  UINT32                   OptCount;\r
  EFI_STATUS               Status;\r
\r
  ASSERT (Dhcp4 != NULL);\r
\r
  Status  = EFI_SUCCESS;\r
  PxeMode = Private->PxeBc.Mode;\r
\r
  //\r
  // Build option list for the request packet.\r
  //\r
  OptCount = PxeBcBuildDhcp4Options (Private, OptList, Buffer, FALSE);\r
  ASSERT (OptCount > 0);\r
\r
  ZeroMem (&Mode, sizeof (EFI_DHCP4_MODE_DATA));\r
  ZeroMem (&Config, sizeof (EFI_DHCP4_CONFIG_DATA));\r
\r
  Config.OptionCount      = OptCount;\r
  Config.OptionList       = OptList;\r
  Config.Dhcp4Callback    = PxeBcDhcp4CallBack;\r
  Config.CallbackContext  = Private;\r
  Config.DiscoverTryCount = PXEBC_DHCP_RETRIES;\r
  Config.DiscoverTimeout  = mPxeDhcpTimeout;\r
\r
  //\r
  // Configure the DHCPv4 instance for PXE boot.\r
  //\r
  Status = Dhcp4->Configure (Dhcp4, &Config);\r
  if (EFI_ERROR (Status)) {\r
    goto ON_EXIT;\r
  }\r
\r
  //\r
  // Initialize the record fields for DHCPv4 offer in private data.\r
  //\r
  Private->IsProxyRecved = FALSE;\r
  Private->OfferNum      = 0;\r
  ZeroMem (Private->OfferCount, sizeof (Private->OfferCount));\r
  ZeroMem (Private->OfferIndex, sizeof (Private->OfferIndex));\r
\r
  Status = Dhcp4->Start (Dhcp4, NULL);\r
  if (EFI_ERROR (Status)) {\r
    if (Status == EFI_ICMP_ERROR) {\r
      PxeMode->IcmpErrorReceived = TRUE;\r
    }\r
\r
    if ((Status == EFI_TIMEOUT) && (Private->OfferNum > 0)) {\r
      Status = EFI_NO_RESPONSE;\r
    }\r
\r
    goto ON_EXIT;\r
  }\r
\r
  //\r
  // Get the acquired IPv4 address and store them.\r
  //\r
  Status = Dhcp4->GetModeData (Dhcp4, &Mode);\r
  if (EFI_ERROR (Status)) {\r
    goto ON_EXIT;\r
  }\r
\r
  ASSERT (Mode.State == Dhcp4Bound);\r
\r
  CopyMem (&Private->StationIp, &Mode.ClientAddress, sizeof (EFI_IPv4_ADDRESS));\r
  CopyMem (&Private->SubnetMask, &Mode.SubnetMask, sizeof (EFI_IPv4_ADDRESS));\r
  CopyMem (&Private->GatewayIp, &Mode.RouterAddress, sizeof (EFI_IPv4_ADDRESS));\r
  CopyMem (&PxeMode->StationIp, &Private->StationIp, sizeof (EFI_IPv4_ADDRESS));\r
  CopyMem (&PxeMode->SubnetMask, &Private->SubnetMask, sizeof (EFI_IPv4_ADDRESS));\r
\r
  Status = PxeBcFlushStationIp (Private, &Private->StationIp, &Private->SubnetMask);\r
  if (EFI_ERROR (Status)) {\r
    goto ON_EXIT;\r
  }\r
\r
  //\r
  // Check the selected offer whether BINL retry is needed.\r
  //\r
  Status = PxeBcHandleDhcp4Offer (Private);\r
\r
  AsciiPrint ("\n  Station IP address is ");\r
\r
  PxeBcShowIp4Addr (&Private->StationIp.v4);\r
  AsciiPrint ("\n");\r
\r
ON_EXIT:\r
  if (EFI_ERROR (Status)) {\r
    Dhcp4->Stop (Dhcp4);\r
    Dhcp4->Configure (Dhcp4, NULL);\r
  } else {\r
    ZeroMem (&Config, sizeof (EFI_DHCP4_CONFIG_DATA));\r
    Dhcp4->Configure (Dhcp4, &Config);\r
    Private->IsAddressOk = TRUE;\r
  }\r
\r
  return Status;\r
}\r