SecurityPkg/Library/AuthVariableLib/AuthServiceInternal.h

   1 /** @file
   2   The internal header file includes the common header files, defines
   3   internal structure and functions used by AuthService module.
   4
   5   Caution: This module requires additional review when modified.
   6   This driver will have external input - variable data. It may be input in SMM mode.
   7   This external input must be validated carefully to avoid security issue like
   8   buffer overflow, integer overflow.
   9   Variable attribute should also be checked to avoid authentication bypass.
  10      The whole SMM authentication variable design relies on the integrity of flash part and SMM.
  11   which is assumed to be protected by platform.  All variable code and metadata in flash/SMM Memory
  12   may not be modified without authorization. If platform fails to protect these resources,
  13   the authentication service provided in this driver will be broken, and the behavior is undefined.
  14
  15 Copyright (c) 2009 - 2018, Intel Corporation. All rights reserved.<BR>
  16 SPDX-License-Identifier: BSD-2-Clause-Patent
  17
  18 **/
  19
  20 #ifndef _AUTHSERVICE_INTERNAL_H_
  21 #define _AUTHSERVICE_INTERNAL_H_
  22
  23 #include <Library/AuthVariableLib.h>
  24 #include <Library/BaseLib.h>
  25 #include <Library/BaseMemoryLib.h>
  26 #include <Library/DebugLib.h>
  27 #include <Library/MemoryAllocationLib.h>
  28 #include <Library/BaseCryptLib.h>
  29 #include <Library/PlatformSecureLib.h>
  30
  31 #include <Guid/AuthenticatedVariableFormat.h>
  32 #include <Guid/ImageAuthentication.h>
  33
  34 #define TWO_BYTE_ENCODE       0x82
  35
  36 ///
  37 /// Struct to record signature requirement defined by UEFI spec.
  38 /// For SigHeaderSize and SigDataSize, ((UINT32) ~0) means NO exact length requirement for this field.
  39 ///
  40 typedef struct {
  41   EFI_GUID    SigType;
  42   // Expected SignatureHeader size in Bytes.
  43   UINT32      SigHeaderSize;
  44   // Expected SignatureData size in Bytes.
  45   UINT32      SigDataSize;
  46 } EFI_SIGNATURE_ITEM;
  47
  48 typedef enum {
  49   AuthVarTypePk,
  50   AuthVarTypeKek,
  51   AuthVarTypePriv,
  52   AuthVarTypePayload
  53 } AUTHVAR_TYPE;
  54
  55 ///
  56 ///  "certdb" variable stores the signer's certificates for non PK/KEK/DB/DBX
  57 /// variables with EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS|EFI_VARIABLE_NON_VOLATILE set.
  58 ///  "certdbv" variable stores the signer's certificates for non PK/KEK/DB/DBX
  59 /// variables with EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS set
  60 ///
  61 /// GUID: gEfiCertDbGuid
  62 ///
  63 /// We need maintain atomicity.
  64 ///
  65 /// Format:
  66 /// +----------------------------+
  67 /// | UINT32                     | <-- CertDbListSize, including this UINT32
  68 /// +----------------------------+
  69 /// | AUTH_CERT_DB_DATA          | <-- First CERT
  70 /// +----------------------------+
  71 /// | ........                   |
  72 /// +----------------------------+
  73 /// | AUTH_CERT_DB_DATA          | <-- Last CERT
  74 /// +----------------------------+
  75 ///
  76 #define EFI_CERT_DB_NAME                 L"certdb"
  77 #define EFI_CERT_DB_VOLATILE_NAME        L"certdbv"
  78
  79 #pragma pack(1)
  80 typedef struct {
  81   EFI_GUID    VendorGuid;
  82   UINT32      CertNodeSize;
  83   UINT32      NameSize;
  84   UINT32      CertDataSize;
  85   /// CHAR16  VariableName[NameSize];
  86   /// UINT8   CertData[CertDataSize];
  87 } AUTH_CERT_DB_DATA;
  88 #pragma pack()
  89
  90 extern UINT8    *mCertDbStore;
  91 extern UINT32   mMaxCertDbSize;
  92 extern UINT32   mPlatformMode;
  93 extern UINT8    mVendorKeyState;
  94
  95 extern VOID     *mHashCtx;
  96
  97 extern AUTH_VAR_LIB_CONTEXT_IN *mAuthVarLibContextIn;
  98
  99
 100 /**
 101   Process variable with EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS set
 102
 103   Caution: This function may receive untrusted input.
 104   This function may be invoked in SMM mode, and datasize and data are external input.
 105   This function will do basic validation, before parse the data.
 106   This function will parse the authentication carefully to avoid security issues, like
 107   buffer overflow, integer overflow.
 108
 109   @param[in]  VariableName                Name of Variable to be found.
 110   @param[in]  VendorGuid                  Variable vendor GUID.
 111   @param[in]  Data                        Data pointer.
 112   @param[in]  DataSize                    Size of Data found. If size is less than the
 113                                           data, this value contains the required size.
 114   @param[in]  Attributes                  Attribute value of the variable.
 115   @param[in]  AuthVarType                 Verify against PK, KEK database, private database or certificate in data payload.
 116   @param[out] VarDel                      Delete the variable or not.
 117
 118   @retval EFI_INVALID_PARAMETER           Invalid parameter.
 119   @retval EFI_SECURITY_VIOLATION          The variable does NOT pass the validation
 120                                           check carried out by the firmware.
 121   @retval EFI_OUT_OF_RESOURCES            Failed to process variable due to lack
 122                                           of resources.
 123   @retval EFI_SUCCESS                     Variable pass validation successfully.
 124
 125 **/
 126 EFI_STATUS
 127 VerifyTimeBasedPayloadAndUpdate (
 128   IN     CHAR16                             *VariableName,
 129   IN     EFI_GUID                           *VendorGuid,
 130   IN     VOID                               *Data,
 131   IN     UINTN                              DataSize,
 132   IN     UINT32                             Attributes,
 133   IN     AUTHVAR_TYPE                       AuthVarType,
 134   OUT    BOOLEAN                            *VarDel
 135   );
 136
 137 /**
 138   Delete matching signer's certificates when deleting common authenticated
 139   variable by corresponding VariableName and VendorGuid from "certdb" or
 140   "certdbv" according to authenticated variable attributes.
 141
 142   @param[in]  VariableName   Name of authenticated Variable.
 143   @param[in]  VendorGuid     Vendor GUID of authenticated Variable.
 144   @param[in]  Attributes        Attributes of authenticated variable.
 145
 146   @retval  EFI_INVALID_PARAMETER Any input parameter is invalid.
 147   @retval  EFI_NOT_FOUND         Fail to find "certdb"/"certdbv" or matching certs.
 148   @retval  EFI_OUT_OF_RESOURCES  The operation is failed due to lack of resources.
 149   @retval  EFI_SUCCESS           The operation is completed successfully.
 150
 151 **/
 152 EFI_STATUS
 153 DeleteCertsFromDb (
 154   IN     CHAR16           *VariableName,
 155   IN     EFI_GUID         *VendorGuid,
 156   IN     UINT32           Attributes
 157   );
 158
 159 /**
 160   Clean up signer's certificates for common authenticated variable
 161   by corresponding VariableName and VendorGuid from "certdb".
 162   System may break down during Timebased Variable update & certdb update,
 163   make them inconsistent,  this function is called in AuthVariable Init to ensure
 164   consistency
 165
 166   @retval  EFI_NOT_FOUND         Fail to find matching certs.
 167   @retval  EFI_SUCCESS           Find matching certs and output parameters.
 168
 169 **/
 170 EFI_STATUS
 171 CleanCertsFromDb (
 172   VOID
 173   );
 174
 175 /**
 176   Filter out the duplicated EFI_SIGNATURE_DATA from the new data by comparing to the original data.
 177
 178   @param[in]        Data          Pointer to original EFI_SIGNATURE_LIST.
 179   @param[in]        DataSize      Size of Data buffer.
 180   @param[in, out]   NewData       Pointer to new EFI_SIGNATURE_LIST.
 181   @param[in, out]   NewDataSize   Size of NewData buffer.
 182
 183 **/
 184 EFI_STATUS
 185 FilterSignatureList (
 186   IN     VOID       *Data,
 187   IN     UINTN      DataSize,
 188   IN OUT VOID       *NewData,
 189   IN OUT UINTN      *NewDataSize
 190   );
 191
 192 /**
 193   Process variable with platform key for verification.
 194
 195   Caution: This function may receive untrusted input.
 196   This function may be invoked in SMM mode, and datasize and data are external input.
 197   This function will do basic validation, before parse the data.
 198   This function will parse the authentication carefully to avoid security issues, like
 199   buffer overflow, integer overflow.
 200   This function will check attribute carefully to avoid authentication bypass.
 201
 202   @param[in]  VariableName                Name of Variable to be found.
 203   @param[in]  VendorGuid                  Variable vendor GUID.
 204   @param[in]  Data                        Data pointer.
 205   @param[in]  DataSize                    Size of Data found. If size is less than the
 206                                           data, this value contains the required size.
 207   @param[in]  Attributes                  Attribute value of the variable
 208   @param[in]  IsPk                        Indicate whether it is to process pk.
 209
 210   @return EFI_INVALID_PARAMETER           Invalid parameter.
 211   @return EFI_SECURITY_VIOLATION          The variable does NOT pass the validation.
 212                                           check carried out by the firmware.
 213   @return EFI_SUCCESS                     Variable passed validation successfully.
 214
 215 **/
 216 EFI_STATUS
 217 ProcessVarWithPk (
 218   IN  CHAR16                    *VariableName,
 219   IN  EFI_GUID                  *VendorGuid,
 220   IN  VOID                      *Data,
 221   IN  UINTN                     DataSize,
 222   IN  UINT32                    Attributes OPTIONAL,
 223   IN  BOOLEAN                   IsPk
 224   );
 225
 226 /**
 227   Process variable with key exchange key for verification.
 228
 229   Caution: This function may receive untrusted input.
 230   This function may be invoked in SMM mode, and datasize and data are external input.
 231   This function will do basic validation, before parse the data.
 232   This function will parse the authentication carefully to avoid security issues, like
 233   buffer overflow, integer overflow.
 234   This function will check attribute carefully to avoid authentication bypass.
 235
 236   @param[in]  VariableName                Name of Variable to be found.
 237   @param[in]  VendorGuid                  Variable vendor GUID.
 238   @param[in]  Data                        Data pointer.
 239   @param[in]  DataSize                    Size of Data found. If size is less than the
 240                                           data, this value contains the required size.
 241   @param[in]  Attributes                  Attribute value of the variable.
 242
 243   @return EFI_INVALID_PARAMETER           Invalid parameter.
 244   @return EFI_SECURITY_VIOLATION          The variable does NOT pass the validation
 245                                           check carried out by the firmware.
 246   @return EFI_SUCCESS                     Variable pass validation successfully.
 247
 248 **/
 249 EFI_STATUS
 250 ProcessVarWithKek (
 251   IN  CHAR16                               *VariableName,
 252   IN  EFI_GUID                             *VendorGuid,
 253   IN  VOID                                 *Data,
 254   IN  UINTN                                DataSize,
 255   IN  UINT32                               Attributes OPTIONAL
 256   );
 257
 258 /**
 259   Process variable with EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS set
 260
 261   Caution: This function may receive untrusted input.
 262   This function may be invoked in SMM mode, and datasize and data are external input.
 263   This function will do basic validation, before parse the data.
 264   This function will parse the authentication carefully to avoid security issues, like
 265   buffer overflow, integer overflow.
 266   This function will check attribute carefully to avoid authentication bypass.
 267
 268   @param[in]  VariableName                Name of the variable.
 269   @param[in]  VendorGuid                  Variable vendor GUID.
 270   @param[in]  Data                        Data pointer.
 271   @param[in]  DataSize                    Size of Data.
 272   @param[in]  Attributes                  Attribute value of the variable.
 273
 274   @return EFI_INVALID_PARAMETER           Invalid parameter.
 275   @return EFI_WRITE_PROTECTED             Variable is write-protected and needs authentication with
 276                                           EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS or EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS set.
 277   @return EFI_OUT_OF_RESOURCES            The Database to save the public key is full.
 278   @return EFI_SECURITY_VIOLATION          The variable is with EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS
 279                                           set, but the AuthInfo does NOT pass the validation
 280                                           check carried out by the firmware.
 281   @return EFI_SUCCESS                     Variable is not write-protected or pass validation successfully.
 282
 283 **/
 284 EFI_STATUS
 285 ProcessVariable (
 286   IN     CHAR16                             *VariableName,
 287   IN     EFI_GUID                           *VendorGuid,
 288   IN     VOID                               *Data,
 289   IN     UINTN                              DataSize,
 290   IN     UINT32                             Attributes
 291   );
 292
 293 /**
 294   Finds variable in storage blocks of volatile and non-volatile storage areas.
 295
 296   This code finds variable in storage blocks of volatile and non-volatile storage areas.
 297   If VariableName is an empty string, then we just return the first
 298   qualified variable without comparing VariableName and VendorGuid.
 299
 300   @param[in]  VariableName          Name of the variable to be found.
 301   @param[in]  VendorGuid            Variable vendor GUID to be found.
 302   @param[out] Data                  Pointer to data address.
 303   @param[out] DataSize              Pointer to data size.
 304
 305   @retval EFI_INVALID_PARAMETER     If VariableName is not an empty string,
 306                                     while VendorGuid is NULL.
 307   @retval EFI_SUCCESS               Variable successfully found.
 308   @retval EFI_NOT_FOUND             Variable not found
 309
 310 **/
 311 EFI_STATUS
 312 AuthServiceInternalFindVariable (
 313   IN  CHAR16        *VariableName,
 314   IN  EFI_GUID      *VendorGuid,
 315   OUT VOID          **Data,
 316   OUT UINTN         *DataSize
 317   );
 318
 319 /**
 320   Update the variable region with Variable information.
 321
 322   @param[in] VariableName           Name of variable.
 323   @param[in] VendorGuid             Guid of variable.
 324   @param[in] Data                   Data pointer.
 325   @param[in] DataSize               Size of Data.
 326   @param[in] Attributes             Attribute value of the variable.
 327
 328   @retval EFI_SUCCESS               The update operation is success.
 329   @retval EFI_INVALID_PARAMETER     Invalid parameter.
 330   @retval EFI_WRITE_PROTECTED       Variable is write-protected.
 331   @retval EFI_OUT_OF_RESOURCES      There is not enough resource.
 332
 333 **/
 334 EFI_STATUS
 335 AuthServiceInternalUpdateVariable (
 336   IN CHAR16         *VariableName,
 337   IN EFI_GUID       *VendorGuid,
 338   IN VOID           *Data,
 339   IN UINTN          DataSize,
 340   IN UINT32         Attributes
 341   );
 342
 343 /**
 344   Update the variable region with Variable information.
 345
 346   @param[in] VariableName           Name of variable.
 347   @param[in] VendorGuid             Guid of variable.
 348   @param[in] Data                   Data pointer.
 349   @param[in] DataSize               Size of Data.
 350   @param[in] Attributes             Attribute value of the variable.
 351   @param[in] TimeStamp              Value of associated TimeStamp.
 352
 353   @retval EFI_SUCCESS               The update operation is success.
 354   @retval EFI_INVALID_PARAMETER     Invalid parameter.
 355   @retval EFI_WRITE_PROTECTED       Variable is write-protected.
 356   @retval EFI_OUT_OF_RESOURCES      There is not enough resource.
 357
 358 **/
 359 EFI_STATUS
 360 AuthServiceInternalUpdateVariableWithTimeStamp (
 361   IN CHAR16         *VariableName,
 362   IN EFI_GUID       *VendorGuid,
 363   IN VOID           *Data,
 364   IN UINTN          DataSize,
 365   IN UINT32         Attributes,
 366   IN EFI_TIME       *TimeStamp
 367   );
 368
 369 #endif