summaryrefslogtreecommitdiff
path: root/MdeModulePkg/Universal/Network/Ip4ConfigDxe/NicIp4Variable.c
blob: a5f00ee645ae7b944f5f33d5885137d32025d7c1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
/** @file
  Routines used to operate the Ip4 configure variable.

Copyright (c) 2006 - 2008, Intel Corporation.<BR>                                                         
All rights reserved. This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution.  The full text of the license may be found at<BR>
http://opensource.org/licenses/bsd-license.php

THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

#include "NicIp4Variable.h"


/**
  Check whether the configure parameter is valid.

  @param  NicConfig    The configure parameter to check

  @return TRUE if the parameter is valid for the interface, otherwise FALSE.

**/
BOOLEAN
Ip4ConfigIsValid (
  IN NIC_IP4_CONFIG_INFO    *NicConfig
  )
{
  EFI_IP4_IPCONFIG_DATA     *IpConfig;
  IP4_ADDR                  Station;
  IP4_ADDR                  Netmask;
  IP4_ADDR                  Gateway;
  UINT32                    Index;

  IpConfig = &NicConfig->Ip4Info;

  if (NicConfig->Source == IP4_CONFIG_SOURCE_STATIC) {
    //
    // Validate that the addresses are unicast and mask
    // is properly formated
    //
    Station = EFI_NTOHL (IpConfig->StationAddress);
    Netmask = EFI_NTOHL (IpConfig->SubnetMask);

    if ((Netmask == 0) || !IP4_IS_VALID_NETMASK (Netmask) ||
        (Station == 0) || !Ip4IsUnicast (Station, Netmask)) {
      return FALSE;
    }

    //
    // Validate that the next hops are on the connected network
    // or that is a direct route (Gateway == 0).
    //
    for (Index = 0; Index < IpConfig->RouteTableSize; Index++) {
      Gateway = EFI_NTOHL (IpConfig->RouteTable[Index].GatewayAddress);

      if ((Gateway != 0) && (!IP4_NET_EQUAL (Station, Gateway, Netmask) ||
          !Ip4IsUnicast (Gateway, Netmask))) {
        return FALSE;
      }
    }

    return TRUE;
  }

  //
  // return false if it is an unkown configure source. Valid
  // sources are static and dhcp.
  //
  return (BOOLEAN) (NicConfig->Source == IP4_CONFIG_SOURCE_DHCP);
}



/**
  Read the ip4 configure variable from the EFI variable.

  None

  @return The IP4 configure read if it is there and is valid, otherwise NULL

**/
IP4_CONFIG_VARIABLE *
Ip4ConfigReadVariable (
  VOID
  )
{
  IP4_CONFIG_VARIABLE       *Variable;
  EFI_STATUS                Status;
  UINTN                     Size;
  UINT16                    CheckSum;

  //
  // Get the size of variable, then allocate a buffer to read the variable.
  //
  Size     = 0;
  Variable = NULL;
  Status   = gRT->GetVariable (
                    EFI_NIC_IP4_CONFIG_VARIABLE,
                    &gEfiNicIp4ConfigVariableGuid,
                    NULL,
                    &Size,
                    NULL
                    );

  if (Status != EFI_BUFFER_TOO_SMALL) {
    return NULL;
  }

  if (Size < sizeof (IP4_CONFIG_VARIABLE)) {
    goto REMOVE_VARIABLE;
  }

  Variable = AllocatePool (Size);

  if (Variable == NULL) {
    return NULL;
  }

  Status = gRT->GetVariable (
                  EFI_NIC_IP4_CONFIG_VARIABLE,
                  &gEfiNicIp4ConfigVariableGuid,
                  NULL,
                  &Size,
                  Variable
                  );

  if (EFI_ERROR (Status)) {
    goto ON_ERROR;
  }

  //
  // Verify the checksum, variable size and count
  //
  CheckSum = (UINT16) (~NetblockChecksum ((UINT8 *) Variable, (UINT32)Size));

  if ((CheckSum != 0) || (Size != Variable->Len)) {
    goto REMOVE_VARIABLE;
  }

  if ((Variable->Count < 1) || (Variable->Count > MAX_IP4_CONFIG_IN_VARIABLE)) {
    goto REMOVE_VARIABLE;
  }

  return Variable;

REMOVE_VARIABLE:
  Ip4ConfigWriteVariable (NULL);

ON_ERROR:
  if (Variable != NULL) {
    gBS->FreePool (Variable);
  }

  return NULL;
}


/**
  Write the IP4 configure variable to the NVRAM. If Config
  is NULL, remove the variable.

  @param  Config       The IP4 configure data to write

  @retval EFI_SUCCESS  The variable is written to the NVRam
  @retval Others       Failed to write the variable.

**/
EFI_STATUS
Ip4ConfigWriteVariable (
  IN IP4_CONFIG_VARIABLE    *Config        OPTIONAL
  )
{
  EFI_STATUS                Status;

  Status = gRT->SetVariable (
                  EFI_NIC_IP4_CONFIG_VARIABLE,
                  &gEfiNicIp4ConfigVariableGuid,
                  IP4_CONFIG_VARIABLE_ATTRIBUTES,
                  (Config == NULL) ? 0 : Config->Len,
                  Config
                  );

  return Status;
}


/**
  Locate the IP4 configure parameters from the variable.If a
  configuration is found, copy it to a newly allocated block
  of memory to avoid the alignment problem. Caller should
  release the memory after use.

  @param  Variable     The IP4 configure variable to search in
  @param  NicAddr      The interface address to check

  @return The point to the NIC's IP4 configure info if it is found
          in the IP4 variable, otherwise NULL.

**/
NIC_IP4_CONFIG_INFO *
Ip4ConfigFindNicVariable (
  IN IP4_CONFIG_VARIABLE    *Variable,
  IN NIC_ADDR               *NicAddr
  )
{
  NIC_IP4_CONFIG_INFO       Temp;
  NIC_IP4_CONFIG_INFO       *Config;
  UINT32                    Index;
  UINT8                     *Cur;
  UINT32                    Len;

  Cur = (UINT8*)&Variable->ConfigInfo;

  for (Index = 0; Index < Variable->Count; Index++) {
    //
    // Copy the data to Temp to avoid the alignment problems
    //
    CopyMem (&Temp, Cur, sizeof (NIC_IP4_CONFIG_INFO));
    Len = SIZEOF_NIC_IP4_CONFIG_INFO (&Temp);

    //
    // Found the matching configuration parameters, allocate
    // a block of memory then copy it out.
    //
    if (NIC_ADDR_EQUAL (&Temp.NicAddr, NicAddr)) {
      Config = AllocatePool (Len);

      if (Config == NULL) {
        return NULL;
      }

      CopyMem (Config, Cur, Len);
      Ip4ConfigFixRouteTablePointer (&Config->Ip4Info);
      return Config;
    }

    Cur += Len;
  }

  return NULL;
}


/**
  Modify the configuration parameter for the NIC in the variable.
  If Config is NULL, old configuration will be remove from the new
  variable. Otherwise, append it or replace the old one.

  @param  Variable     The IP4 variable to change
  @param  NicAddr      The interface to search
  @param  Config       The new configuration parameter (NULL to remove the old)

  @return The new IP4_CONFIG_VARIABLE variable if the new variable has at
          least one NIC configure and no EFI_OUT_OF_RESOURCES failure.
          Return NULL either because failed to locate memory for new variable
          or the only NIC configure is removed from the Variable.

**/
IP4_CONFIG_VARIABLE *
Ip4ConfigModifyVariable (
  IN IP4_CONFIG_VARIABLE    *Variable     OPTIONAL,
  IN NIC_ADDR               *NicAddr,
  IN NIC_IP4_CONFIG_INFO    *Config       OPTIONAL
  )
{
  NIC_IP4_CONFIG_INFO       Temp;
  NIC_IP4_CONFIG_INFO       *Old;
  IP4_CONFIG_VARIABLE       *NewVar;
  UINT32                    Len;
  UINT32                    TotalLen;
  UINT32                    Count;
  UINT8                     *Next;
  UINT8                     *Cur;
  UINT32                    Index;

  ASSERT ((Variable != NULL) || (Config != NULL));

  //
  // Compute the total length
  //
  if (Variable != NULL) {
    //
    // Variable != NULL, then Config can be NULL or not.  and so is
    // the Old. If old configure exists, it is removed from the
    // Variable. New configure is append to the variable.
    //
    //
    Count     = Variable->Count;
    Cur       = (UINT8 *)&Variable->ConfigInfo;
    TotalLen  = Variable->Len;

    Old       = Ip4ConfigFindNicVariable (Variable, NicAddr);

    if (Old != NULL) {
      TotalLen -= SIZEOF_NIC_IP4_CONFIG_INFO (Old);
      gBS->FreePool (Old);
    }

    if (Config != NULL) {
      TotalLen += SIZEOF_NIC_IP4_CONFIG_INFO (Config);
    }

    //
    // Return NULL if the only NIC_IP4_CONFIG_INFO is being removed.
    //
    if (TotalLen < sizeof (IP4_CONFIG_VARIABLE)) {
      return NULL;
    }

  } else {
    //
    // Variable == NULL and Config != NULL, Create a new variable with
    // this NIC configure.
    //
    Count     = 0;
    Cur       = NULL;
    TotalLen  = sizeof (IP4_CONFIG_VARIABLE) - sizeof (NIC_IP4_CONFIG_INFO)
                + SIZEOF_NIC_IP4_CONFIG_INFO (Config);
  }

  ASSERT (TotalLen >= sizeof (IP4_CONFIG_VARIABLE));

  NewVar = AllocateZeroPool (TotalLen);

  if (NewVar == NULL) {
    return NULL;
  }

  NewVar->Len = TotalLen;

  //
  // Copy the other configure parameters from the old variable
  //
  Next = (UINT8 *)&NewVar->ConfigInfo;

  for (Index = 0; Index < Count; Index++) {
    CopyMem (&Temp, Cur, sizeof (NIC_IP4_CONFIG_INFO));
    Len = SIZEOF_NIC_IP4_CONFIG_INFO (&Temp);

    if (!NIC_ADDR_EQUAL (&Temp.NicAddr, NicAddr)) {
      CopyMem (Next, Cur, Len);
      Next += Len;
      NewVar->Count++;
    }

    Cur += Len;
  }

  //
  // Append the new configure if it isn't NULL.
  //
  Len = 0;

  if (Config != NULL) {
    Len = SIZEOF_NIC_IP4_CONFIG_INFO (Config);

    CopyMem (Next, Config, Len);
    NewVar->Count++;
  }

  ASSERT (Next + Len == (UINT8 *) NewVar + TotalLen);

  NewVar->CheckSum = (UINT16) (~NetblockChecksum ((UINT8 *) NewVar, TotalLen));
  return NewVar;
}

/**
  Fix the RouteTable pointer in an EFI_IP4_IPCONFIG_DATA structure. 
  
  The pointer is set to be immediately follow the ConfigData if there're entries
  in the RouteTable. Otherwise it is set to NULL.
  
  @param  ConfigData     The IP4 IP configure data.

**/
VOID
Ip4ConfigFixRouteTablePointer (
  IN OUT EFI_IP4_IPCONFIG_DATA  *ConfigData
  )
{
  //
  // The memory used for route table entries must immediately follow 
  // the ConfigData and be not packed.
  //
  if (ConfigData->RouteTableSize > 0) {
    ConfigData->RouteTable = (EFI_IP4_ROUTE_TABLE *) (ConfigData + 1);
  } else {
    ConfigData->RouteTable = NULL;
  }
}