MdeModulePkg/Universal/Network/Ip4ConfigDxe/NicIp4Variable.c

   1 /** @file
   2
   3 Copyright (c) 2006 - 2008, 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       Ip4ConfigFixRouteTablePointer (&Config->Ip4Info);
 253       return Config;
 254     }
 255
 256     Cur += Len;
 257   }
 258
 259   return NULL;
 260 }
 261
 262
 263 /**
 264   Modify the configuration parameter for the NIC in the variable.
 265   If Config is NULL, old configuration will be remove from the new
 266   variable. Otherwise, append it or replace the old one.
 267
 268   @param  Variable     The IP4 variable to change
 269   @param  NicAddr      The interface to search
 270   @param  Config       The new configuration parameter (NULL to remove the old)
 271
 272   @return The new IP4_CONFIG_VARIABLE variable if the new variable has at
 273   @return least one NIC configure and no EFI_OUT_OF_RESOURCES failure.
 274   @return Return NULL either because failed to locate memory for new variable
 275   @return or the only NIC configure is removed from the Variable.
 276
 277 **/
 278 IP4_CONFIG_VARIABLE *
 279 Ip4ConfigModifyVariable (
 280   IN IP4_CONFIG_VARIABLE    *Variable,    OPTIONAL
 281   IN NIC_ADDR               *NicAddr,
 282   IN NIC_IP4_CONFIG_INFO    *Config       OPTIONAL
 283   )
 284 {
 285   NIC_IP4_CONFIG_INFO       Temp;
 286   NIC_IP4_CONFIG_INFO       *Old;
 287   IP4_CONFIG_VARIABLE       *NewVar;
 288   UINT32                    Len;
 289   UINT32                    TotalLen;
 290   UINT32                    Count;
 291   UINT8                     *Next;
 292   UINT8                     *Cur;
 293   UINT32                    Index;
 294
 295   ASSERT ((Variable != NULL) || (Config != NULL));
 296
 297   //
 298   // Compute the total length
 299   //
 300   if (Variable != NULL) {
 301     //
 302     // Variable != NULL, then Config can be NULL or not.  and so is
 303     // the Old. If old configure exists, it is removed from the
 304     // Variable. New configure is append to the variable.
 305     //
 306     //
 307     Count     = Variable->Count;
 308     Cur       = (UINT8 *)&Variable->ConfigInfo;
 309     TotalLen  = Variable->Len;
 310
 311     Old       = Ip4ConfigFindNicVariable (Variable, NicAddr);
 312
 313     if (Old != NULL) {
 314       TotalLen -= SIZEOF_NIC_IP4_CONFIG_INFO (Old);
 315       gBS->FreePool (Old);
 316     }
 317
 318     if (Config != NULL) {
 319       TotalLen += SIZEOF_NIC_IP4_CONFIG_INFO (Config);
 320     }
 321
 322     //
 323     // Return NULL if the only NIC_IP4_CONFIG_INFO is being removed.
 324     //
 325     if (TotalLen < sizeof (IP4_CONFIG_VARIABLE)) {
 326       return NULL;
 327     }
 328
 329   } else {
 330     //
 331     // Variable == NULL and Config != NULL, Create a new variable with
 332     // this NIC configure.
 333     //
 334     Count     = 0;
 335     Cur       = NULL;
 336     TotalLen  = sizeof (IP4_CONFIG_VARIABLE) - sizeof (NIC_IP4_CONFIG_INFO)
 337                 + SIZEOF_NIC_IP4_CONFIG_INFO (Config);
 338   }
 339
 340   ASSERT (TotalLen >= sizeof (IP4_CONFIG_VARIABLE));
 341
 342   NewVar = AllocateZeroPool (TotalLen);
 343
 344   if (NewVar == NULL) {
 345     return NULL;
 346   }
 347
 348   NewVar->Len = TotalLen;
 349
 350   //
 351   // Copy the other configure parameters from the old variable
 352   //
 353   Next = (UINT8 *)&NewVar->ConfigInfo;
 354
 355   for (Index = 0; Index < Count; Index++) {
 356     CopyMem (&Temp, Cur, sizeof (NIC_IP4_CONFIG_INFO));
 357     Len = SIZEOF_NIC_IP4_CONFIG_INFO (&Temp);
 358
 359     if (!NIC_ADDR_EQUAL (&Temp.NicAddr, NicAddr)) {
 360       CopyMem (Next, Cur, Len);
 361       Next += Len;
 362       NewVar->Count++;
 363     }
 364
 365     Cur += Len;
 366   }
 367
 368   //
 369   // Append the new configure if it isn't NULL.
 370   //
 371   Len = 0;
 372
 373   if (Config != NULL) {
 374     Len = SIZEOF_NIC_IP4_CONFIG_INFO (Config);
 375
 376     CopyMem (Next, Config, Len);
 377     NewVar->Count++;
 378   }
 379
 380   ASSERT (Next + Len == (UINT8 *) NewVar + TotalLen);
 381
 382   NewVar->CheckSum = (UINT16) (~NetblockChecksum ((UINT8 *) NewVar, TotalLen));
 383   return NewVar;
 384 }
 385
 386 VOID
 387 Ip4ConfigFixRouteTablePointer (
 388   IN EFI_IP4_IPCONFIG_DATA  *ConfigData
 389   )
 390 {
 391   //
 392   // The memory used for route table entries must immediately follow
 393   // the ConfigData and be not packed.
 394   //
 395   if (ConfigData->RouteTableSize > 0) {
 396     ConfigData->RouteTable = (EFI_IP4_ROUTE_TABLE *) (ConfigData + 1);
 397   } else {
 398     ConfigData->RouteTable = NULL;
 399   }
 400 }
 401