[mirror_edk2.git] / NetworkPkg / HttpBootDxe / HttpBootDhcp4.c

/** @file\r
  Functions implementation related with DHCPv4 for HTTP boot driver.\r
\r
Copyright (c) 2015 - 2018, Intel Corporation. All rights reserved.<BR>\r
SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include "HttpBootDxe.h"\r
\r
//\r
// This is a map from the interested DHCP4 option tags' index to the tag value.\r
//\r
UINT8 mInterestedDhcp4Tags[HTTP_BOOT_DHCP4_TAG_INDEX_MAX] = {\r
  DHCP4_TAG_BOOTFILE_LEN,\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
  DHCP4_TAG_DNS_SERVER\r
};\r
\r
//\r
// There are 4 times retries with the value of 4, 8, 16 and 32, refers to UEFI 2.5 spec.\r
//\r
UINT32 mHttpDhcpTimeout[4] = {4, 8, 16, 32};\r
\r
/**\r
  Build the options buffer for the DHCPv4 request packet.\r
\r
  @param[in]  Private             Pointer to HTTP boot driver 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
\r
  @return     Index               The count of the built-in options.\r
\r
**/\r
UINT32\r
HttpBootBuildDhcp4Options (\r
  IN  HTTP_BOOT_PRIVATE_DATA        *Private,\r
  OUT EFI_DHCP4_PACKET_OPTION       **OptList,\r
  IN  UINT8                         *Buffer\r
  )\r
{\r
  HTTP_BOOT_DHCP4_OPTION_ENTRY  OptEnt;\r
  UINT16                        Value;\r
  UINT32                        Index;\r
\r
  Index      = 0;\r
  OptList[0] = (EFI_DHCP4_PACKET_OPTION *) Buffer;\r
\r
  //\r
  // Append parameter request list option.\r
  //\r
  OptList[Index]->OpCode    = DHCP4_TAG_PARA_LIST;\r
  OptList[Index]->Length    = 27;\r
  OptEnt.Para               = (HTTP_BOOT_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[25] = DHCP4_TAG_BOOTFILE;\r
  OptEnt.Para->ParaList[26] = DHCP4_TAG_UUID;\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 (HTTP_BOOT_DHCP4_OPTION_UUID);\r
  OptEnt.Uuid             = (HTTP_BOOT_DHCP4_OPTION_UUID *) OptList[Index]->Data;\r
  OptEnt.Uuid->Type       = 0;\r
  if (EFI_ERROR (NetLibGetSystemGuid ((EFI_GUID *) OptEnt.Uuid->Guid))) {\r
    //\r
    // Zero the Guid to indicate NOT programable if failed to get system Guid.\r
    //\r
    ZeroMem (OptEnt.Uuid->Guid, sizeof (EFI_GUID));\r
  }\r
  Index++;\r
  OptList[Index]          = GET_NEXT_DHCP_OPTION (OptList[Index - 1]);\r
\r
  //\r
  // Append client network device interface option\r
  //\r
  OptList[Index]->OpCode  = DHCP4_TAG_UNDI;\r
  OptList[Index]->Length  = (UINT8) sizeof (HTTP_BOOT_DHCP4_OPTION_UNDI);\r
  OptEnt.Undi             = (HTTP_BOOT_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 (HTTP_BOOT_DHCP4_OPTION_ARCH);\r
  OptEnt.Arch             = (HTTP_BOOT_DHCP4_OPTION_ARCH *) OptList[Index]->Data;\r
  Value                   = HTONS (EFI_HTTP_BOOT_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 (HTTP_BOOT_DHCP4_OPTION_CLID);\r
  OptEnt.Clid             = (HTTP_BOOT_DHCP4_OPTION_CLID *) OptList[Index]->Data;\r
  CopyMem (\r
    OptEnt.Clid,\r
    DEFAULT_CLASS_ID_DATA,\r
    sizeof (HTTP_BOOT_DHCP4_OPTION_CLID)\r
    );\r
  HttpBootUintnToAscDecWithFormat (\r
    EFI_HTTP_BOOT_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
    HttpBootUintnToAscDecWithFormat (Private->Nii->MajorVer, OptEnt.Clid->UndiMajor, sizeof (OptEnt.Clid->UndiMajor));\r
    HttpBootUintnToAscDecWithFormat (Private->Nii->MinorVer, OptEnt.Clid->UndiMinor, sizeof (OptEnt.Clid->UndiMinor));\r
  }\r
\r
  Index++;\r
\r
  return Index;\r
}\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
HttpBootParseDhcp4Options (\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
\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
  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
HttpBootCacheDhcp4Packet (\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 an invalid packet.\r
\r
**/\r
EFI_STATUS\r
HttpBootParseDhcp4Packet (\r
  IN HTTP_BOOT_DHCP4_PACKET_CACHE    *Cache4\r
  )\r
{\r
  EFI_DHCP4_PACKET               *Offer;\r
  EFI_DHCP4_PACKET_OPTION        **Options;\r
  UINTN                          Index;\r
  EFI_DHCP4_PACKET_OPTION        *Option;\r
  BOOLEAN                        IsProxyOffer;\r
  BOOLEAN                        IsHttpOffer;\r
  BOOLEAN                        IsDnsOffer;\r
  BOOLEAN                        IpExpressedUri;\r
  UINT8                          *Ptr8;\r
  EFI_STATUS                     Status;\r
  HTTP_BOOT_OFFER_TYPE           OfferType;\r
  EFI_IPv4_ADDRESS               IpAddr;\r
  BOOLEAN                        FileFieldOverloaded;\r
\r
  IsDnsOffer     = FALSE;\r
  IpExpressedUri = FALSE;\r
  IsProxyOffer   = FALSE;\r
  IsHttpOffer    = FALSE;\r
  FileFieldOverloaded = FALSE;\r
\r
  ZeroMem (Cache4->OptList, sizeof (Cache4->OptList));\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 < HTTP_BOOT_DHCP4_TAG_INDEX_MAX; Index++) {\r
    Options[Index] = HttpBootParseDhcp4Options (\r
                       Offer->Dhcp4.Option,\r
                       GET_OPTION_BUFFER_LEN (Offer),\r
                       mInterestedDhcp4Tags[Index]\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[HTTP_BOOT_DHCP4_TAG_INDEX_OVERLOAD];\r
  if (Option != NULL) {\r
    if ((Option->Data[0] & HTTP_BOOT_DHCP4_OVERLOAD_FILE) != 0) {\r
      FileFieldOverloaded = TRUE;\r
      for (Index = 0; Index < HTTP_BOOT_DHCP4_TAG_INDEX_MAX; Index++) {\r
        if (Options[Index] == NULL) {\r
          Options[Index] = HttpBootParseDhcp4Options (\r
                             (UINT8 *) Offer->Dhcp4.Header.BootFileName,\r
                             sizeof (Offer->Dhcp4.Header.BootFileName),\r
                             mInterestedDhcp4Tags[Index]\r
                             );\r
        }\r
      }\r
    }\r
    if ((Option->Data[0] & HTTP_BOOT_DHCP4_OVERLOAD_SERVER_NAME) != 0) {\r
      for (Index = 0; Index < HTTP_BOOT_DHCP4_TAG_INDEX_MAX; Index++) {\r
        if (Options[Index] == NULL) {\r
          Options[Index] = HttpBootParseDhcp4Options (\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 "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 "HTTPClient" is a Http offer.\r
  //\r
  Option = Options[HTTP_BOOT_DHCP4_TAG_INDEX_CLASS_ID];\r
  if ((Option != NULL) && (Option->Length >= 10) &&\r
      (CompareMem (Option->Data, DEFAULT_CLASS_ID_DATA, 10) == 0)) {\r
    IsHttpOffer = TRUE;\r
  }\r
\r
  //\r
  // The offer with Domain Server is a DNS offer.\r
  //\r
  Option = Options[HTTP_BOOT_DHCP4_TAG_INDEX_DNS_SERVER];\r
  if (Option != NULL) {\r
    IsDnsOffer = TRUE;\r
  }\r
\r
  //\r
  // Parse boot file name:\r
  // Boot URI information is provided thru 'file' field in DHCP Header or option 67.\r
  // According to RFC 2132, 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[HTTP_BOOT_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[HTTP_BOOT_DHCP4_TAG_INDEX_BOOTFILE]->Data[0];\r
    Ptr8 += Options[HTTP_BOOT_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[HTTP_BOOT_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
  // Http offer must have a boot URI.\r
  //\r
  if (IsHttpOffer && Options[HTTP_BOOT_DHCP4_TAG_INDEX_BOOTFILE] == NULL) {\r
    return EFI_DEVICE_ERROR;\r
  }\r
\r
  //\r
  // Try to retrieve the IP of HTTP server from URI.\r
  //\r
  if (IsHttpOffer) {\r
    Status = HttpParseUrl (\r
               (CHAR8*) Options[HTTP_BOOT_DHCP4_TAG_INDEX_BOOTFILE]->Data,\r
               (UINT32) AsciiStrLen ((CHAR8*) Options[HTTP_BOOT_DHCP4_TAG_INDEX_BOOTFILE]->Data),\r
               FALSE,\r
               &Cache4->UriParser\r
               );\r
    if (EFI_ERROR (Status)) {\r
      return EFI_DEVICE_ERROR;\r
    }\r
\r
    Status = HttpUrlGetIp4 (\r
               (CHAR8*) Options[HTTP_BOOT_DHCP4_TAG_INDEX_BOOTFILE]->Data,\r
               Cache4->UriParser,\r
               &IpAddr\r
               );\r
    IpExpressedUri = !EFI_ERROR (Status);\r
  }\r
\r
  //\r
  // Determine offer type of the DHCPv4 packet.\r
  //\r
  if (IsHttpOffer) {\r
    if (IpExpressedUri) {\r
      if (IsProxyOffer) {\r
        OfferType = HttpOfferTypeProxyIpUri;\r
      } else {\r
        OfferType = IsDnsOffer ? HttpOfferTypeDhcpIpUriDns : HttpOfferTypeDhcpIpUri;\r
      }\r
    } else {\r
      if (!IsProxyOffer) {\r
        OfferType = IsDnsOffer ? HttpOfferTypeDhcpNameUriDns : HttpOfferTypeDhcpNameUri;\r
      } else {\r
        OfferType = HttpOfferTypeProxyNameUri;\r
      }\r
    }\r
\r
  } else {\r
    if (!IsProxyOffer) {\r
      OfferType = IsDnsOffer ? HttpOfferTypeDhcpDns : HttpOfferTypeDhcpOnly;\r
    } else {\r
      if (Cache4->UriParser != NULL) {\r
        FreePool (Cache4->UriParser);\r
      }\r
      return EFI_DEVICE_ERROR;\r
    }\r
  }\r
\r
  Cache4->OfferType = OfferType;\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 HTTP boot driver 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
EFI_STATUS\r
HttpBootCacheDhcp4Offer (\r
  IN HTTP_BOOT_PRIVATE_DATA  *Private,\r
  IN EFI_DHCP4_PACKET        *RcvdOffer\r
  )\r
{\r
  HTTP_BOOT_DHCP4_PACKET_CACHE  *Cache4;\r
  EFI_DHCP4_PACKET              *Offer;\r
  HTTP_BOOT_OFFER_TYPE          OfferType;\r
  EFI_STATUS                    Status;\r
\r
  ASSERT (Private->OfferNum < HTTP_BOOT_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 = HttpBootCacheDhcp4Packet (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 (HttpBootParseDhcp4Packet (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 < HttpOfferTypeMax);\r
  ASSERT (Private->OfferCount[OfferType] < HTTP_BOOT_OFFER_MAX_NUM);\r
  Private->OfferIndex[OfferType][Private->OfferCount[OfferType]] = Private->OfferNum;\r
  Private->OfferCount[OfferType]++;\r
  Private->OfferNum++;\r
\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  Select an DHCPv4 or DHCP6 offer, and record SelectIndex and SelectProxyType.\r
\r
  @param[in]  Private             Pointer to HTTP boot driver private data.\r
\r
**/\r
VOID\r
HttpBootSelectDhcpOffer (\r
  IN HTTP_BOOT_PRIVATE_DATA  *Private\r
  )\r
{\r
  Private->SelectIndex = 0;\r
  Private->SelectProxyType = HttpOfferTypeMax;\r
\r
  if (Private->FilePathUri != NULL) {\r
    //\r
    // We are in home environment, the URI is already specified.\r
    // Just need to choose a DHCP offer.\r
    // The offer with DNS server address takes priority here.\r
    //\r
    if (Private->OfferCount[HttpOfferTypeDhcpDns] > 0) {\r
\r
      Private->SelectIndex = Private->OfferIndex[HttpOfferTypeDhcpDns][0] + 1;\r
\r
    } else if (Private->OfferCount[HttpOfferTypeDhcpIpUriDns] > 0) {\r
\r
      Private->SelectIndex = Private->OfferIndex[HttpOfferTypeDhcpIpUriDns][0] + 1;\r
\r
    } else if (Private->OfferCount[HttpOfferTypeDhcpNameUriDns] > 0) {\r
\r
      Private->SelectIndex = Private->OfferIndex[HttpOfferTypeDhcpNameUriDns][0] + 1;\r
\r
    }  else if (Private->OfferCount[HttpOfferTypeDhcpOnly] > 0) {\r
\r
      Private->SelectIndex = Private->OfferIndex[HttpOfferTypeDhcpOnly][0] + 1;\r
\r
    }  else if (Private->OfferCount[HttpOfferTypeDhcpIpUri] > 0) {\r
\r
      Private->SelectIndex = Private->OfferIndex[HttpOfferTypeDhcpIpUri][0] + 1;\r
    }\r
\r
  } else {\r
    //\r
    // We are in corporate environment.\r
    //\r
    // Priority1: HttpOfferTypeDhcpIpUri or HttpOfferTypeDhcpIpUriDns\r
    // Priority2: HttpOfferTypeDhcpNameUriDns\r
    // Priority3: HttpOfferTypeDhcpOnly + HttpOfferTypeProxyIpUri\r
    // Priority4: HttpOfferTypeDhcpDns  + HttpOfferTypeProxyIpUri\r
    // Priority5: HttpOfferTypeDhcpDns  + HttpOfferTypeProxyNameUri\r
    // Priority6: HttpOfferTypeDhcpDns  + HttpOfferTypeDhcpNameUri\r
    //\r
    if (Private->OfferCount[HttpOfferTypeDhcpIpUri] > 0) {\r
\r
      Private->SelectIndex = Private->OfferIndex[HttpOfferTypeDhcpIpUri][0] + 1;\r
\r
    } else if (Private->OfferCount[HttpOfferTypeDhcpIpUriDns] > 0) {\r
\r
      Private->SelectIndex = Private->OfferIndex[HttpOfferTypeDhcpIpUriDns][0] + 1;\r
\r
    }else if (Private->OfferCount[HttpOfferTypeDhcpNameUriDns] > 0) {\r
\r
      Private->SelectIndex = Private->OfferIndex[HttpOfferTypeDhcpNameUriDns][0] + 1;\r
\r
    } else if (Private->OfferCount[HttpOfferTypeDhcpOnly] > 0 &&\r
               Private->OfferCount[HttpOfferTypeProxyIpUri] > 0) {\r
\r
      Private->SelectIndex     = Private->OfferIndex[HttpOfferTypeDhcpOnly][0] + 1;\r
      Private->SelectProxyType = HttpOfferTypeProxyIpUri;\r
\r
    } else if (Private->OfferCount[HttpOfferTypeDhcpDns] > 0 &&\r
               Private->OfferCount[HttpOfferTypeProxyIpUri] > 0) {\r
\r
      Private->SelectIndex     = Private->OfferIndex[HttpOfferTypeDhcpDns][0] + 1;\r
      Private->SelectProxyType = HttpOfferTypeProxyIpUri;\r
\r
    } else if (Private->OfferCount[HttpOfferTypeDhcpDns] > 0 &&\r
               Private->OfferCount[HttpOfferTypeProxyNameUri] > 0) {\r
\r
      Private->SelectIndex     = Private->OfferIndex[HttpOfferTypeDhcpDns][0] + 1;\r
      Private->SelectProxyType = HttpOfferTypeProxyNameUri;\r
\r
    } else if (Private->OfferCount[HttpOfferTypeDhcpDns] > 0 &&\r
               Private->OfferCount[HttpOfferTypeDhcpNameUri] > 0) {\r
\r
      Private->SelectIndex     = Private->OfferIndex[HttpOfferTypeDhcpDns][0] + 1;\r
      Private->SelectProxyType = HttpOfferTypeDhcpNameUri;\r
    }\r
  }\r
}\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
HttpBootDhcp4CallBack (\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
  HTTP_BOOT_PRIVATE_DATA               *Private;\r
  EFI_DHCP4_PACKET_OPTION              *MaxMsgSize;\r
  UINT16                               Value;\r
  EFI_STATUS                           Status;\r
  BOOLEAN                              Received;\r
\r
  if ((Dhcp4Event != Dhcp4SendDiscover) &&\r
      (Dhcp4Event != Dhcp4RcvdOffer) &&\r
      (Dhcp4Event != Dhcp4SendRequest) &&\r
      (Dhcp4Event != Dhcp4RcvdAck) &&\r
      (Dhcp4Event != Dhcp4SelectOffer)) {\r
    return EFI_SUCCESS;\r
  }\r
\r
  Private = (HTTP_BOOT_PRIVATE_DATA *) Context;\r
\r
  //\r
  // Override the Maximum DHCP Message Size.\r
  //\r
  MaxMsgSize = HttpBootParseDhcp4Options (\r
                 Packet->Dhcp4.Option,\r
                 GET_OPTION_BUFFER_LEN (Packet),\r
                 DHCP4_TAG_MAXMSG\r
                 );\r
  if (MaxMsgSize != NULL) {\r
    Value = HTONS (HTTP_BOOT_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 (Private->HttpBootCallback != NULL && Dhcp4Event != Dhcp4SelectOffer) {\r
    Received = (BOOLEAN) (Dhcp4Event == Dhcp4RcvdOffer || Dhcp4Event == Dhcp4RcvdAck);\r
    Status = Private->HttpBootCallback->Callback (\r
               Private->HttpBootCallback,\r
               HttpBootDhcp4,\r
               Received,\r
               Packet->Length,\r
               &Packet->Dhcp4\r
               );\r
    if (EFI_ERROR (Status)) {\r
      return EFI_ABORTED;\r
    }\r
  }\r
\r
  Status = EFI_SUCCESS;\r
  switch (Dhcp4Event) {\r
  case Dhcp4RcvdOffer:\r
    Status = EFI_NOT_READY;\r
    if (Packet->Length > HTTP_BOOT_DHCP4_PACKET_MAX_SIZE) {\r
      //\r
      // Ignore the incoming packets which exceed the maximum length.\r
      //\r
      break;\r
    }\r
    if (Private->OfferNum < HTTP_BOOT_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
      HttpBootCacheDhcp4Offer (Private, Packet);\r
    }\r
    break;\r
\r
  case Dhcp4SelectOffer:\r
    //\r
    // Select offer according to the priority in UEFI spec, and record the SelectIndex\r
    // and SelectProxyType.\r
    //\r
    HttpBootSelectDhcpOffer (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
    break;\r
\r
  default:\r
    break;\r
  }\r
\r
  return Status;\r
}\r
\r
/**\r
  This function will register the IPv4 gateway address to the network device.\r
\r
  @param[in]  Private             The pointer to HTTP_BOOT_PRIVATE_DATA.\r
\r
  @retval     EFI_SUCCESS         The new IP configuration has been configured successfully.\r
  @retval     Others              Failed to configure the address.\r
\r
**/\r
EFI_STATUS\r
HttpBootRegisterIp4Gateway (\r
  IN HTTP_BOOT_PRIVATE_DATA         *Private\r
  )\r
{\r
  EFI_STATUS                      Status;\r
  EFI_IP4_CONFIG2_PROTOCOL        *Ip4Config2;\r
\r
  ASSERT (!Private->UsingIpv6);\r
\r
  Ip4Config2 = Private->Ip4Config2;\r
\r
  //\r
  // Configure the gateway if valid.\r
  //\r
  if (!EFI_IP4_EQUAL (&Private->GatewayIp, &mZeroIp4Addr)) {\r
    Status = Ip4Config2->SetData (\r
                           Ip4Config2,\r
                           Ip4Config2DataTypeGateway,\r
                           sizeof (EFI_IPv4_ADDRESS),\r
                           &Private->GatewayIp\r
                           );\r
    if (EFI_ERROR (Status)) {\r
      return Status;\r
    }\r
  }\r
\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  This function will register the default DNS addresses to the network device.\r
\r
  @param[in]  Private             The pointer to HTTP_BOOT_PRIVATE_DATA.\r
  @param[in]  DataLength          Size of the buffer pointed to by DnsServerData in bytes.\r
  @param[in]  DnsServerData       Point a list of DNS server address in an array\r
                                  of EFI_IPv4_ADDRESS instances.\r
\r
  @retval     EFI_SUCCESS         The DNS configuration has been configured successfully.\r
  @retval     Others              Failed to configure the address.\r
\r
**/\r
EFI_STATUS\r
HttpBootRegisterIp4Dns (\r
  IN HTTP_BOOT_PRIVATE_DATA         *Private,\r
  IN UINTN                          DataLength,\r
  IN VOID                           *DnsServerData\r
  )\r
{\r
  EFI_IP4_CONFIG2_PROTOCOL        *Ip4Config2;\r
\r
  ASSERT (!Private->UsingIpv6);\r
\r
  Ip4Config2 = Private->Ip4Config2;\r
\r
  return Ip4Config2->SetData (\r
                       Ip4Config2,\r
                       Ip4Config2DataTypeDnsServer,\r
                       DataLength,\r
                       DnsServerData\r
                       );\r
}\r
\r
\r
/**\r
  This function will switch the IP4 configuration policy to Static.\r
\r
  @param[in]  Private             Pointer to HTTP boot driver 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
HttpBootSetIp4Policy (\r
  IN HTTP_BOOT_PRIVATE_DATA         *Private\r
  )\r
{\r
  EFI_IP4_CONFIG2_POLICY          Policy;\r
  EFI_STATUS                      Status;\r
  EFI_IP4_CONFIG2_PROTOCOL        *Ip4Config2;\r
  UINTN                           DataSize;\r
\r
  Ip4Config2 = Private->Ip4Config2;\r
\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 Http boot information.\r
\r
  @param[in]  Private           Pointer to HTTP boot driver private data.\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
HttpBootDhcp4Dora (\r
  IN HTTP_BOOT_PRIVATE_DATA         *Private\r
  )\r
{\r
  EFI_DHCP4_PROTOCOL           *Dhcp4;\r
  UINT32                       OptCount;\r
  EFI_DHCP4_PACKET_OPTION      *OptList[HTTP_BOOT_DHCP4_OPTION_MAX_NUM];\r
  UINT8                        Buffer[HTTP_BOOT_DHCP4_OPTION_MAX_SIZE];\r
  EFI_DHCP4_CONFIG_DATA        Config;\r
  EFI_STATUS                   Status;\r
  EFI_DHCP4_MODE_DATA          Mode;\r
\r
  Dhcp4 = Private->Dhcp4;\r
  ASSERT (Dhcp4 != NULL);\r
\r
  Status = HttpBootSetIp4Policy (Private);\r
  if (EFI_ERROR (Status)) {\r
    return Status;\r
  }\r
\r
  //\r
  // Build option list for the request packet.\r
  //\r
  OptCount = HttpBootBuildDhcp4Options (Private, OptList, Buffer);\r
  ASSERT (OptCount > 0);\r
\r
  ZeroMem (&Config, sizeof(Config));\r
  Config.OptionCount      = OptCount;\r
  Config.OptionList       = OptList;\r
  Config.Dhcp4Callback    = HttpBootDhcp4CallBack;\r
  Config.CallbackContext  = Private;\r
  Config.DiscoverTryCount = HTTP_BOOT_DHCP_RETRIES;\r
  Config.DiscoverTimeout  = mHttpDhcpTimeout;\r
\r
  //\r
  // Configure the DHCPv4 instance for HTTP 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->OfferNum = 0;\r
  ZeroMem (Private->OfferCount, sizeof (Private->OfferCount));\r
  ZeroMem (Private->OfferIndex, sizeof (Private->OfferIndex));\r
\r
  //\r
  // Start DHCPv4 D.O.R.A. process to acquire IPv4 address.\r
  //\r
  Status = Dhcp4->Start (Dhcp4, NULL);\r
  if (EFI_ERROR (Status)) {\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
  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
\r
  Status = HttpBootRegisterIp4Gateway (Private);\r
  if (EFI_ERROR (Status)) {\r
    goto ON_EXIT;\r
  }\r
\r
  AsciiPrint ("\n  Station IP address is ");\r
  HttpBootShowIp4Addr (&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
  }\r
\r
  return Status;\r
}\r