Add comment for modules which have external input.

[mirror_edk2.git] / SecurityPkg / VariableAuthenticated / RuntimeDxe / AuthService.c

diff --git a/SecurityPkg/VariableAuthenticated/RuntimeDxe/AuthService.c b/SecurityPkg/VariableAuthenticated/RuntimeDxe/AuthService.c
index a3b620f02a94bcffd2c77d4d08e6b6e4f57f22ca..d6df32affc27f9ca8c3de4753b37a539741db300 100644 (file)
--- a/SecurityPkg/VariableAuthenticated/RuntimeDxe/AuthService.c
+++ b/SecurityPkg/VariableAuthenticated/RuntimeDxe/AuthService.c
@@ -2,6 +2,19 @@
   Implement authentication services for the authenticated variable\r
   service in UEFI2.2.\r
 \r
+  Caution: This module requires additional review when modified.\r
+  This driver will have external input - variable data. It may be input in SMM mode.\r
+  This external input must be validated carefully to avoid security issue like\r
+  buffer overflow, integer overflow.\r
+  Variable attribute should also be checked to avoid authentication bypass.\r
+\r
+  ProcessVarWithPk(), ProcessVarWithKek() and ProcessVariable() are the function to do\r
+  variable authentication.\r
+\r
+  VerifyTimeBasedPayload() and VerifyCounterBasedPayload() are sub function to do verification.\r
+  They will do basic validation for authentication data structure, then call crypto library\r
+  to verify the signature.\r
+\r
 Copyright (c) 2009 - 2012, Intel Corporation. All rights reserved.<BR>\r
 This program and the accompanying materials\r
 are licensed and made available under the terms and conditions of the BSD License\r
@@ -502,6 +515,12 @@ AddPubKeyInStore (
   Verify data payload with AuthInfo in EFI_CERT_TYPE_RSA2048_SHA256_GUID type.\r
   Follow the steps in UEFI2.2.\r
 \r
+  Caution: This function may receive untrusted input.\r
+  This function may be invoked in SMM mode, and datasize and data are external input.\r
+  This function will do basic validation, before parse the data.\r
+  This function will parse the authentication carefully to avoid security issues, like\r
+  buffer overflow, integer overflow.\r
+\r
   @param[in]      Data                    Pointer to data with AuthInfo.\r
   @param[in]      DataSize                Size of Data.\r
   @param[in]      PubKey                  Public key used for verification.\r
@@ -852,6 +871,13 @@ CheckSignatureListFormat(
 /**\r
   Process variable with platform key for verification.\r
 \r
+  Caution: This function may receive untrusted input.\r
+  This function may be invoked in SMM mode, and datasize and data are external input.\r
+  This function will do basic validation, before parse the data.\r
+  This function will parse the authentication carefully to avoid security issues, like\r
+  buffer overflow, integer overflow.\r
+  This function will check attribute carefully to avoid authentication bypass.\r
+\r
   @param[in]  VariableName                Name of Variable to be found.\r
   @param[in]  VendorGuid                  Variable vendor GUID.\r
   @param[in]  Data                        Data pointer.\r
@@ -961,6 +987,13 @@ ProcessVarWithPk (
 /**\r
   Process variable with key exchange key for verification.\r
 \r
+  Caution: This function may receive untrusted input.\r
+  This function may be invoked in SMM mode, and datasize and data are external input.\r
+  This function will do basic validation, before parse the data.\r
+  This function will parse the authentication carefully to avoid security issues, like\r
+  buffer overflow, integer overflow.\r
+  This function will check attribute carefully to avoid authentication bypass.\r
+\r
   @param[in]  VariableName                Name of Variable to be found.\r
   @param[in]  VendorGuid                  Variable vendor GUID.\r
   @param[in]  Data                        Data pointer.\r
@@ -1039,6 +1072,13 @@ ProcessVarWithKek (
 /**\r
   Process variable with EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS/EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS set\r
 \r
+  Caution: This function may receive untrusted input.\r
+  This function may be invoked in SMM mode, and datasize and data are external input.\r
+  This function will do basic validation, before parse the data.\r
+  This function will parse the authentication carefully to avoid security issues, like\r
+  buffer overflow, integer overflow.\r
+  This function will check attribute carefully to avoid authentication bypass.\r
+\r
   @param[in]  VariableName                Name of Variable to be found.\r
   @param[in]  VendorGuid                  Variable vendor GUID.\r
 \r
@@ -1806,6 +1846,12 @@ InsertCertsToDb (
 /**\r
   Process variable with EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS set\r
 \r
+  Caution: This function may receive untrusted input.\r
+  This function may be invoked in SMM mode, and datasize and data are external input.\r
+  This function will do basic validation, before parse the data.\r
+  This function will parse the authentication carefully to avoid security issues, like\r
+  buffer overflow, integer overflow.\r
+\r
   @param[in]  VariableName                Name of Variable to be found.\r
   @param[in]  VendorGuid                  Variable vendor GUID.\r
   @param[in]  Data                        Data pointer.\r