MdeModulePkg/Universal/Network/Ip4ConfigDxe/NicIp4Variable.c

   1 /** @file
   2
   3 Copyright (c) 2006, 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
  14   NicIp4Variable.c
  15
  16 Abstract:
  17
  18   Routines used to operate the Ip4 configure variable
  19
  20
  21 **/
  22
  23
  24 #include <Library/NetLib.h>
  25 #include <Library/DebugLib.h>
  26 #include <Library/BaseMemoryLib.h>
  27 #include <Library/MemoryAllocationLib.h>
  28 #include <Library/UefiBootServicesTableLib.h>
  29 #include <Library/UefiRuntimeServicesTableLib.h>
  30
  31 #include "NicIp4Variable.h"
  32
  33
  34 /**
  35   Check whether the configure parameter is valid.
  36
  37   @param  NicConfig    The configure parameter to check
  38
  39   @return TRUE if the parameter is valid for the interface, otherwise FALSE.
  40
  41 **/
  42 BOOLEAN
  43 Ip4ConfigIsValid (
  44   IN NIC_IP4_CONFIG_INFO    *NicConfig
  45   )
  46 {
  47   EFI_IP4_IPCONFIG_DATA     *IpConfig;
  48   IP4_ADDR                  Station;
  49   IP4_ADDR                  Netmask;
  50   IP4_ADDR                  Gateway;
  51   UINT32                    Index;
  52
  53   IpConfig = &NicConfig->Ip4Info;
  54
  55   if (NicConfig->Source == IP4_CONFIG_SOURCE_STATIC) {
  56     //
  57     // Validate that the addresses are unicast and mask
  58     // is properly formated
  59     //
  60     Station = EFI_NTOHL (IpConfig->StationAddress);
  61     Netmask = EFI_NTOHL (IpConfig->SubnetMask);
  62
  63     if ((Netmask == 0) || !IP4_IS_VALID_NETMASK (Netmask) ||
  64         (Station == 0) || !Ip4IsUnicast (Station, Netmask)) {
  65       return FALSE;
  66     }
  67
  68     //
  69     // Validate that the next hops are on the connected network
  70     // or that is a direct route (Gateway == 0).
  71     //
  72     for (Index = 0; Index < IpConfig->RouteTableSize; Index++) {
  73       Gateway = EFI_NTOHL (IpConfig->RouteTable[Index].GatewayAddress);
  74
  75       if ((Gateway != 0) && (!IP4_NET_EQUAL (Station, Gateway, Netmask) ||
  76           !Ip4IsUnicast (Gateway, Netmask))) {
  77         return FALSE;
  78       }
  79     }
  80
  81     return TRUE;
  82   }
  83
  84   //
  85   // return false if it is an unkown configure source. Valid
  86   // sources are static and dhcp.
  87   //
  88   return (BOOLEAN) (NicConfig->Source == IP4_CONFIG_SOURCE_DHCP);
  89 }
  90
  91
  92
  93 /**
  94   Read the ip4 configure variable from the EFI variable
  95
  96   None
  97
  98   @return The IP4 configure read if it is there and is valid, otherwise NULL
  99
 100 **/
 101 IP4_CONFIG_VARIABLE *
 102 Ip4ConfigReadVariable (
 103   VOID
 104   )
 105 {
 106   IP4_CONFIG_VARIABLE       *Variable;
 107   EFI_STATUS                Status;
 108   UINTN                     Size;
 109   UINT16                    CheckSum;
 110
 111   //
 112   // Get the size of variable, then allocate a buffer to read the variable.
 113   //
 114   Size     = 0;
 115   Variable = NULL;
 116   Status   = gRT->GetVariable (
 117                     EFI_NIC_IP4_CONFIG_VARIABLE,
 118                     &gEfiNicIp4ConfigVariableGuid,
 119                     NULL,
 120                     &Size,
 121                     NULL
 122                     );
 123
 124   if (Status != EFI_BUFFER_TOO_SMALL) {
 125     return NULL;
 126   }
 127
 128   if (Size < sizeof (IP4_CONFIG_VARIABLE)) {
 129     goto REMOVE_VARIABLE;
 130   }
 131
 132   Variable = AllocatePool (Size);
 133
 134   if (Variable == NULL) {
 135     return NULL;
 136   }
 137
 138   Status = gRT->GetVariable (
 139                   EFI_NIC_IP4_CONFIG_VARIABLE,
 140                   &gEfiNicIp4ConfigVariableGuid,
 141                   NULL,
 142                   &Size,
 143                   Variable
 144                   );
 145
 146   if (EFI_ERROR (Status)) {
 147     goto ON_ERROR;
 148   }
 149
 150   //
 151   // Verify the checksum, variable size and count
 152   //
 153   CheckSum = (UINT16) (~NetblockChecksum ((UINT8 *) Variable, (UINT32)Size));
 154
 155   if ((CheckSum != 0) || (Size != Variable->Len)) {
 156     goto REMOVE_VARIABLE;
 157   }
 158
 159   if ((Variable->Count < 1) || (Variable->Count > MAX_IP4_CONFIG_IN_VARIABLE)) {
 160     goto REMOVE_VARIABLE;
 161   }
 162
 163   return Variable;
 164
 165 REMOVE_VARIABLE:
 166   Ip4ConfigWriteVariable (NULL);
 167
 168 ON_ERROR:
 169   if (Variable != NULL) {
 170     gBS->FreePool (Variable);
 171   }
 172
 173   return NULL;
 174 }
 175
 176
 177 /**
 178   Write the IP4 configure variable to the NVRAM. If Config
 179   is NULL, remove the variable.
 180
 181   @param  Config       The IP4 configure data to write
 182
 183   @retval EFI_SUCCESS  The variable is written to the NVRam
 184   @retval Others       Failed to write the variable.
 185
 186 **/
 187 EFI_STATUS
 188 Ip4ConfigWriteVariable (
 189   IN IP4_CONFIG_VARIABLE    * Config        OPTIONAL
 190   )
 191 {
 192   EFI_STATUS                Status;
 193
 194   Status = gRT->SetVariable (
 195                   EFI_NIC_IP4_CONFIG_VARIABLE,
 196                   &gEfiNicIp4ConfigVariableGuid,
 197                   IP4_CONFIG_VARIABLE_ATTRIBUTES,
 198                   (Config == NULL) ? 0 : Config->Len,
 199                   Config
 200                   );
 201
 202   return Status;
 203 }
 204
 205
 206 /**
 207   Locate the IP4 configure parameters from the variable.If a
 208   configuration is found, copy it to a newly allocated block
 209   of memory to avoid the alignment problem. Caller should
 210   release the memory after use.
 211
 212   @param  Variable     The IP4 configure variable to search in
 213   @param  NicAddr      The interface address to check
 214
 215   @return The point to the NIC's IP4 configure info if it is found
 216   @return in the IP4 variable, otherwise NULL.
 217
 218 **/
 219 NIC_IP4_CONFIG_INFO *
 220 Ip4ConfigFindNicVariable (
 221   IN IP4_CONFIG_VARIABLE    *Variable,
 222   IN NIC_ADDR               *NicAddr
 223   )
 224 {
 225   NIC_IP4_CONFIG_INFO       Temp;
 226   NIC_IP4_CONFIG_INFO       *Config;
 227   UINT32                    Index;
 228   UINT8                     *Cur;
 229   UINT32                    Len;
 230
 231   Cur = (UINT8*)&Variable->ConfigInfo;
 232
 233   for (Index = 0; Index < Variable->Count; Index++) {
 234     //
 235     // Copy the data to Temp to avoid the alignment problems
 236     //
 237     CopyMem (&Temp, Cur, sizeof (NIC_IP4_CONFIG_INFO));
 238     Len = SIZEOF_NIC_IP4_CONFIG_INFO (&Temp);
 239
 240     //
 241     // Found the matching configuration parameters, allocate
 242     // a block of memory then copy it out.
 243     //
 244     if (NIC_ADDR_EQUAL (&Temp.NicAddr, NicAddr)) {
 245       Config = AllocatePool (Len);
 246
 247       if (Config == NULL) {
 248         return NULL;
 249       }
 250
 251       CopyMem (Config, Cur, Len);
 252       return Config;
 253     }
 254
 255     Cur += Len;
 256   }
 257
 258   return NULL;
 259 }
 260
 261
 262 /**
 263   Modify the configuration parameter for the NIC in the variable.
 264   If Config is NULL, old configuration will be remove from the new
 265   variable. Otherwise, append it or replace the old one.
 266
 267   @param  Variable     The IP4 variable to change
 268   @param  NicAddr      The interface to search
 269   @param  Config       The new configuration parameter (NULL to remove the old)
 270
 271   @return The new IP4_CONFIG_VARIABLE variable if the new variable has at
 272   @return least one NIC configure and no EFI_OUT_OF_RESOURCES failure.
 273   @return Return NULL either because failed to locate memory for new variable
 274   @return or the only NIC configure is removed from the Variable.
 275
 276 **/
 277 IP4_CONFIG_VARIABLE *
 278 Ip4ConfigModifyVariable (
 279   IN IP4_CONFIG_VARIABLE    *Variable,    OPTIONAL
 280   IN NIC_ADDR               *NicAddr,
 281   IN NIC_IP4_CONFIG_INFO    *Config       OPTIONAL
 282   )
 283 {
 284   NIC_IP4_CONFIG_INFO       Temp;
 285   NIC_IP4_CONFIG_INFO       *Old;
 286   IP4_CONFIG_VARIABLE       *NewVar;
 287   UINT32                    Len;
 288   UINT32                    TotalLen;
 289   UINT32                    Count;
 290   UINT8                     *Next;
 291   UINT8                     *Cur;
 292   UINT32                    Index;
 293
 294   ASSERT ((Variable != NULL) || (Config != NULL));
 295
 296   //
 297   // Compute the total length
 298   //
 299   if (Variable != NULL) {
 300     //
 301     // Variable != NULL, then Config can be NULL or not.  and so is
 302     // the Old. If old configure exists, it is removed from the
 303     // Variable. New configure is append to the variable.
 304     //
 305     //
 306     Count     = Variable->Count;
 307     Cur       = (UINT8 *)&Variable->ConfigInfo;
 308     TotalLen  = Variable->Len;
 309
 310     Old       = Ip4ConfigFindNicVariable (Variable, NicAddr);
 311
 312     if (Old != NULL) {
 313       TotalLen -= SIZEOF_NIC_IP4_CONFIG_INFO (Old);
 314       gBS->FreePool (Old);
 315     }
 316
 317     if (Config != NULL) {
 318       TotalLen += SIZEOF_NIC_IP4_CONFIG_INFO (Config);
 319     }
 320
 321     //
 322     // Return NULL if the only NIC_IP4_CONFIG_INFO is being removed.
 323     //
 324     if (TotalLen < sizeof (IP4_CONFIG_VARIABLE)) {
 325       return NULL;
 326     }
 327
 328   } else {
 329     //
 330     // Variable == NULL and Config != NULL, Create a new variable with
 331     // this NIC configure.
 332     //
 333     Count     = 0;
 334     Cur       = NULL;
 335     TotalLen  = sizeof (IP4_CONFIG_VARIABLE) - sizeof (NIC_IP4_CONFIG_INFO)
 336                 + SIZEOF_NIC_IP4_CONFIG_INFO (Config);
 337   }
 338
 339   ASSERT (TotalLen >= sizeof (IP4_CONFIG_VARIABLE));
 340
 341   NewVar = AllocateZeroPool (TotalLen);
 342
 343   if (NewVar == NULL) {
 344     return NULL;
 345   }
 346
 347   NewVar->Len = TotalLen;
 348
 349   //
 350   // Copy the other configure parameters from the old variable
 351   //
 352   Next = (UINT8 *)&NewVar->ConfigInfo;
 353
 354   for (Index = 0; Index < Count; Index++) {
 355     CopyMem (&Temp, Cur, sizeof (NIC_IP4_CONFIG_INFO));
 356     Len = SIZEOF_NIC_IP4_CONFIG_INFO (&Temp);
 357
 358     if (!NIC_ADDR_EQUAL (&Temp.NicAddr, NicAddr)) {
 359       CopyMem (Next, Cur, Len);
 360       Next += Len;
 361       NewVar->Count++;
 362     }
 363
 364     Cur += Len;
 365   }
 366
 367   //
 368   // Append the new configure if it isn't NULL.
 369   //
 370   Len = 0;
 371
 372   if (Config != NULL) {
 373     Len = SIZEOF_NIC_IP4_CONFIG_INFO (Config);
 374
 375     CopyMem (Next, Config, Len);
 376     NewVar->Count++;
 377   }
 378
 379   ASSERT (Next + Len == (UINT8 *) NewVar + TotalLen);
 380
 381   NewVar->CheckSum = (UINT16) (~NetblockChecksum ((UINT8 *) NewVar, TotalLen));
 382   return NewVar;
 383 }