MdeModulePkg/Universal/Network/PxeDhcp4Dxe/PxeDhcp4Run.c

   1 /** @file
   2
   3 Copyright (c) 2004 - 2007, Intel Corporation
   4 All rights reserved. This program and the accompanying materials
   5 are licensed and made available under the terms and conditions of the BSD License
   6 which accompanies this distribution.  The full text of the license may be found at
   7 http://opensource.org/licenses/bsd-license.php
   8
   9 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11
  12 Module Name:
  13   PxeDhcp4Run.c
  14
  15 Abstract:
  16   Simplified entry point for starting basic PxeDhcp4 client operation.
  17
  18
  19 **/
  20
  21
  22 #include "PxeDhcp4.h"
  23
  24 EFI_STATUS
  25 EFIAPI
  26 PxeDhcp4Run (
  27   IN EFI_PXE_DHCP4_PROTOCOL *This,
  28   IN OPTIONAL UINTN                  OpLen,
  29   IN OPTIONAL VOID                   *OpList
  30   )
  31 {
  32   PXE_DHCP4_PRIVATE_DATA  *Private;
  33   DHCP4_PACKET            *offer_list;
  34   EFI_STATUS              efi_status;
  35   EFI_IP_ADDRESS          zero_ip;
  36   UINTN                   offers;
  37   UINTN                   timeout;
  38   UINTN                   n;
  39   UINT16                  seconds;
  40
  41   //
  42   // Validate parameters.
  43   //
  44   if (This == NULL || (OpLen != 0 && OpList == NULL) || (OpLen == 0 && OpList != NULL)) {
  45     return EFI_INVALID_PARAMETER;
  46   }
  47
  48   for (n = 0; n < OpLen;) {
  49     switch (((UINT8 *) OpList)[n]) {
  50     case DHCP4_PAD:
  51       ++n;
  52       continue;
  53
  54     case DHCP4_END:
  55       ++n;
  56       break;
  57
  58     default:
  59       n += 2 + ((UINT8 *) OpList)[n + 1];
  60       continue;
  61     }
  62
  63     break;
  64   }
  65
  66   if (n != OpLen) {
  67     return EFI_INVALID_PARAMETER;
  68   }
  69   //
  70   // Get pointer to instance data.
  71   //
  72   Private = PXE_DHCP4_PRIVATE_DATA_FROM_THIS (This);
  73
  74   if (Private == NULL) {
  75     return EFI_INVALID_PARAMETER;
  76   }
  77
  78   if (Private->PxeBc == NULL) {
  79     return EFI_DEVICE_ERROR;
  80   }
  81   //
  82   // Initialize DHCP discover packet.
  83   //
  84   efi_status = PxeDhcp4Setup (This, NULL);
  85
  86   if (EFI_ERROR (efi_status)) {
  87     return efi_status;
  88   }
  89
  90   for (n = 0; n < OpLen;) {
  91     switch (((UINT8 *) OpList)[n]) {
  92     case DHCP4_PAD:
  93       ++n;
  94       continue;
  95
  96     case DHCP4_END:
  97       ++n;
  98       break;
  99
 100     default:
 101       efi_status = add_opt (
 102                     &This->Data->Discover,
 103                     (DHCP4_OP *) &(((UINT8 *) OpList)[n])
 104                     );
 105
 106       if (EFI_ERROR (efi_status)) {
 107         return efi_status;
 108       }
 109
 110       n += 2 + ((UINT8 *) OpList)[n + 1];
 111       continue;
 112     }
 113
 114     break;
 115   }
 116   //
 117   // Basic DHCP D.O.R.A.
 118   // 1, 2, 4, 8, 16 & 32 second timeouts.
 119   // Callback routine can be used to break out earlier.
 120   //
 121   ZeroMem (&zero_ip, sizeof (EFI_IP_ADDRESS));
 122
 123   for (timeout = 1;;) {
 124     //
 125     // Broadcast DHCP discover and wait for DHCP offers.
 126     //
 127     efi_status = PxeDhcp4Init (This, timeout, &offers, &offer_list);
 128
 129     if ((efi_status != EFI_SUCCESS) &&
 130         (efi_status != EFI_TIMEOUT) &&
 131         (efi_status != EFI_NO_RESPONSE)) {
 132       return efi_status;
 133     }
 134     //
 135     // Try to select from each DHCP or BOOTP offer.
 136     //
 137     for (n = 0; n < offers; ++n) {
 138       //
 139       // Ignore proxyDHCP offers.
 140       //
 141       if (!CompareMem (&offer_list[n].dhcp4.yiaddr, &zero_ip, 4)) {
 142         continue;
 143       }
 144       //
 145       // Issue DHCP Request and wait for DHCP Ack/Nak.
 146       //
 147       efi_status = PxeDhcp4Select (
 148                     This,
 149                     timeout,
 150                     &offer_list[n]
 151                     );
 152
 153       if (EFI_ERROR (efi_status)) {
 154         continue;
 155       }
 156       //
 157       // Exit when we have got our DHCP Ack.
 158       //
 159       if (This->Data->IsAck) {
 160         return EFI_SUCCESS;
 161       }
 162     }
 163     //
 164     // No DHCP Acks.  Release DHCP Offer list storage.
 165     //
 166     if (offer_list != NULL) {
 167       gBS->FreePool (offer_list);
 168       offer_list = NULL;
 169     }
 170     //
 171     // Try again until we have used up >= DHCP4_MAX_SECONDS.
 172     //
 173     if ((timeout <<= 1) > DHCP4_MAX_SECONDS) {
 174       if (!EFI_ERROR (efi_status)) {
 175         efi_status = EFI_TIMEOUT;
 176       }
 177
 178       return efi_status;
 179     }
 180     //
 181     // Next timeout value.
 182     //
 183     CopyMem (&seconds, &This->Data->Discover.dhcp4.secs, 2);
 184
 185     seconds = htons (htons (seconds) + timeout);
 186
 187     CopyMem (&This->Data->Discover.dhcp4.secs, &seconds, 2);
 188   }
 189 }
 190
 191 /* eof - PxeDhcp4Run.c */