Re: [PATCH] RedfishPkg/RedfishPlatformCredentialIpmiLib: IPMI implementation

["Nickle Wang" <nicklew@nvidia.com>]

Hi Igor,

Thank you for your review. I will incorporate your comments in version 2 patch files.

Regards,
Nickle

-----Original Message-----
From: Igor Kulchytskyy <igork@ami.com> 
Sent: Saturday, March 11, 2023 2:49 AM
To: Nickle Wang <nicklew@nvidia.com>; devel@edk2.groups.io
Cc: Abner Chang <abner.chang@amd.com>; Nick Ramirez <nramirez@nvidia.com>
Subject: RE: [EXTERNAL] [PATCH] RedfishPkg/RedfishPlatformCredentialIpmiLib: IPMI implementation

External email: Use caution opening links or attachments


Hi Nickle,
See my comments below the text.
Thank you,
Igor

-----Original Message-----
From: Nickle Wang <nicklew@nvidia.com>
Sent: Wednesday, March 8, 2023 2:21 AM
To: devel@edk2.groups.io
Cc: Abner Chang <abner.chang@amd.com>; Igor Kulchytskyy <igork@ami.com>; Nick Ramirez <nramirez@nvidia.com>
Subject: [EXTERNAL] [PATCH] RedfishPkg/RedfishPlatformCredentialIpmiLib: IPMI implementation


**CAUTION: The e-mail below is from an external source. Please exercise caution before opening attachments, clicking links, or following guidance.**

This library follows Redfish Host Interface specification and use IPMI command to get bootstrap account credential(NetFn 2Ch, Command 02h) from BMC. RedfishHostInterfaceDxe will use this credential for the following communication between BIOS and BMC.

Signed-off-by: Nickle Wang <nicklew@nvidia.com>
Cc: Abner Chang <abner.chang@amd.com>
Cc: Igor Kulchytskyy <igork@ami.com>
Cc: Nick Ramirez <nramirez@nvidia.com>
---
 .../RedfishPlatformCredentialIpmiLib.c        | 443 ++++++++++++++++++
 .../RedfishPlatformCredentialIpmiLib.h        |  86 ++++
 .../RedfishPlatformCredentialIpmiLib.inf      |  42 ++
 RedfishPkg/RedfishPkg.dec                     |   7 +
 RedfishPkg/RedfishPkg.dsc                     |   2 +
 5 files changed, 580 insertions(+)
 create mode 100644 RedfishPkg/Library/RedfishPlatformCredentialIpmi/RedfishPlatformCredentialIpmiLib.c
 create mode 100644 RedfishPkg/Library/RedfishPlatformCredentialIpmi/RedfishPlatformCredentialIpmiLib.h
 create mode 100644 RedfishPkg/Library/RedfishPlatformCredentialIpmi/RedfishPlatformCredentialIpmiLib.inf

diff --git a/RedfishPkg/Library/RedfishPlatformCredentialIpmi/RedfishPlatformCredentialIpmiLib.c b/RedfishPkg/Library/RedfishPlatformCredentialIpmi/RedfishPlatformCredentialIpmiLib.c
new file mode 100644
index 0000000000..2706b8508b
--- /dev/null
+++ b/RedfishPkg/Library/RedfishPlatformCredentialIpmi/RedfishPlatformCr
+++ edentialIpmiLib.c
@@ -0,0 +1,443 @@
+/** @file
+  Implementation of getting bootstrap credential via IPMI.
+
+  Copyright (c) 2022-2023 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+  @par Specification Reference:
+  - Redfish Host Interface Specification
+  
+(https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.
+dmtf.org%2Fsites%2Fdefault%2Ffiles%2Fstandards%2Fdocuments%2FDSP0270_1.
+3.0.pdf&data=05%7C01%7Cnicklew%40nvidia.com%7Cc2a7584372a24c0bade608db2
+198250c%7C43083d15727340c1b7db39efd9ccc17a%7C0%7C0%7C638140709577922520
+%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik
+1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=oUyyzInu9QxV2Fq0wvt1Z2TrEtMk
+z2gS52TEIn%2Ftc3Y%3D&reserved=0)
+**/
+
+#include "RedfishPlatformCredentialIpmiLib.h"
+
+//
+// Global flag of controlling credential service // BOOLEAN  
+mRedfishServiceStopped = FALSE;
+
+/**
+  Notify the Redfish service provide to stop provide configuration service to this platform.
+
+  This function should be called when the platform is about to leave the safe environment.
+  It will notify the Redfish service provider to abort all login 
+ session, and prohibit  further login with original auth info. 
+ GetAuthInfo() will return EFI_UNSUPPORTED once this  function is returned.
+
+  @param[in]   This                Pointer to EDKII_REDFISH_CREDENTIAL_PROTOCOL instance.
+  @param[in]   ServiceStopType     Reason of stopping Redfish service.
+
+  @retval EFI_SUCCESS              Service has been stoped successfully.
+  @retval EFI_INVALID_PARAMETER    This is NULL.
+  @retval Others                   Some error happened.
+
+**/
+EFI_STATUS
+EFIAPI
+LibStopRedfishService (
+  IN     EDKII_REDFISH_CREDENTIAL_PROTOCOL           *This,
+  IN     EDKII_REDFISH_CREDENTIAL_STOP_SERVICE_TYPE  ServiceStopType
+  )
+{
+  EFI_STATUS  Status;
+
+  if ((ServiceStopType <= ServiceStopTypeNone) || (ServiceStopType >= ServiceStopTypeMax)) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // Only stop credential service after leaving BIOS  //  if 
+ (ServiceStopType != ServiceStopTypeExitBootService) {
+    return EFI_UNSUPPORTED;
+  }
+
+  //
+  // Raise flag first
+  //
+  mRedfishServiceStopped = TRUE;
+
+  //
+  // Notify BMC to disable credential bootstrapping support.
+  //
+  if (PcdGetBool (PcdRedfishDisableBootstrapCredentialService)) {
+    Status = GetBootstrapAccountCredentials (TRUE, NULL, NULL);
+    if (EFI_ERROR (Status)) {
+      DEBUG ((DEBUG_ERROR, "%a: fail to disable bootstrap credential: %r\n", __FUNCTION__, Status));
+      return Status;
+    }
+  }

Why should we call IPMI function to disable bootstrap credentials here?
This call will create new account on BMC side with username and password, which is not going to be used anyway (we even do not save those credentials).
We already have a call of IPMI function first time we need the credentials.
Then we agreed to cash them in NVRAM variable and all other calls to get credentials will use the credentials from that NVRAM variable.
Shouldn't we use that PCD and send the corresponding flag to IPMI command during our first call.
I do not see any differences for Redfish modules as it explained above, but we may save some boot time (timeout for IPMI command is 5 sec). And there will be no spare bootstrap account on BMC side created.
.
+
+  //
+  // Delete cached variable
+  //
+  Status = SetBootstrapAccountCredentialsToVariable (NULL, NULL, TRUE);  
+ if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_ERROR, "%a: fail to remove bootstrap credential: 
+ %r\n", __FUNCTION__, Status));  }
+
+  DEBUG ((DEBUG_INFO, "%a: bootstrap credential service stopped\n", 
+ __FUNCTION__));
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Notification of Exit Boot Service.
+
+  @param[in]  This    Pointer to EDKII_REDFISH_CREDENTIAL_PROTOCOL.
+**/
+VOID
+EFIAPI
+LibCredentialExitBootServicesNotify (
+  IN  EDKII_REDFISH_CREDENTIAL_PROTOCOL  *This
+  )
+{
+  //
+  // Stop the credential support when system is about to enter OS.
+  //
+  LibStopRedfishService (This, ServiceStopTypeExitBootService); }
+
+/**
+  Notification of End of DXe.
+
+  @param[in]  This    Pointer to EDKII_REDFISH_CREDENTIAL_PROTOCOL.
+**/
+VOID
+EFIAPI
+LibCredentialEndOfDxeNotify (
+  IN  EDKII_REDFISH_CREDENTIAL_PROTOCOL  *This
+  )
+{
+  //
+  // Do nothing now.
+  // We can stop credential support when system reach end-of-dxe for security reason.
+  //
+}
+
+/**
+  Function to retrieve temporary user credentials for the UEFI redfish 
+client. This function can
+  also disable bootstrap credential service in BMC.
+
+  @param[in]  DisableBootstrapControl
+                                      TRUE - Tell the BMC to disable the bootstrap credential
+                                             service to ensure no one else gains credentials
+                                      FALSE  Allow the bootstrap 
+ credential service to continue  @param[in,out] BootstrapUsername
+                                      A pointer to a Ascii encoded string for the credential username
+                                      When DisableBootstrapControl is 
+ TRUE, this pointer can be NULL
+
+  @param[in,out] BootstrapPassword
+                                      A pointer to a Ascii encoded string for the credential password
+                                      When DisableBootstrapControl is 
+ TRUE, this pointer can be NULL
+
+  @retval  EFI_SUCCESS                Credentials were successfully fetched and returned. When DisableBootstrapControl
+                                      is set to TRUE, the bootstrap credential service is disabled successfully.
+  @retval  EFI_INVALID_PARAMETER      BootstrapUsername or BootstrapPassword is NULL when DisableBootstrapControl
+                                      is set to FALSE
+  @retval  EFI_DEVICE_ERROR           An IPMI failure occurred
+**/
+EFI_STATUS
+GetBootstrapAccountCredentials (
+  IN BOOLEAN DisableBootstrapControl,
+  IN OUT CHAR8 *BootstrapUsername, OPTIONAL
+  IN OUT CHAR8  *BootstrapPassword    OPTIONAL
+  )
+{
+  EFI_STATUS                                  Status;
+  IPMI_BOOTSTRAP_CREDENTIALS_COMMAND_DATA     CommandData;
+  IPMI_BOOTSTRAP_CREDENTIALS_RESULT_RESPONSE  ResponseData;
+  UINT32                                      ResponseSize;
+
+  //
+  // NULL buffer check
+  //
+  if (!DisableBootstrapControl && ((BootstrapUsername == NULL) || (BootstrapPassword == NULL))) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  DEBUG ((DEBUG_VERBOSE, "%a: Disable bootstrap control: 0x%x\n", 
+ __FUNCTION__, DisableBootstrapControl));
+
+  //
+  // IPMI callout to NetFn 2C, command 02
+  //    Request data:
+  //      Byte 1: REDFISH_IPMI_GROUP_EXTENSION
+  //      Byte 2: DisableBootstrapControl
+  //
+  CommandData.GroupExtensionId        = REDFISH_IPMI_GROUP_EXTENSION;
+  CommandData.DisableBootstrapControl = (DisableBootstrapControl ? 
+ REDFISH_IPMI_BOOTSTRAP_CREDENTIAL_DISABLE : 
+ REDFISH_IPMI_BOOTSTRAP_CREDENTIAL_ENABLE);
+
+  ResponseSize = sizeof (ResponseData);
+
+  //
+  //    Response data:
+  //      Byte 1    : Completion code
+  //      Byte 2    : REDFISH_IPMI_GROUP_EXTENSION
+  //      Byte 3-18 : Username
+  //      Byte 19-34: Password
+  //
+  Status = IpmiSubmitCommand (
+             IPMI_NETFN_GROUP_EXT,
+             REDFISH_IPMI_GET_BOOTSTRAP_CREDENTIALS_CMD,
+             (UINT8 *)&CommandData,
+             sizeof (CommandData),
+             (UINT8 *)&ResponseData,
+             &ResponseSize
+             );
+
+  if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_ERROR, "%a: IPMI transaction failure. Returning\n", __FUNCTION__));
+    return Status;
+  } else {
+    if (ResponseData.CompletionCode != IPMI_COMP_CODE_NORMAL) {
+      if (ResponseData.CompletionCode == REDFISH_IPMI_COMP_CODE_BOOTSTRAP_CREDENTIAL_DISABLED) {
+        DEBUG ((DEBUG_ERROR, "%a: bootstrap credential support was disabled\n", __FUNCTION__));
+        return EFI_ACCESS_DENIED;
+      }
+
+      DEBUG ((DEBUG_ERROR, "%a: Completion code = 0x%x. Returning\n", __FUNCTION__, ResponseData.CompletionCode));
+      return EFI_PROTOCOL_ERROR;
+    } else if (ResponseData.GroupExtensionId != REDFISH_IPMI_GROUP_EXTENSION) {
+      DEBUG ((DEBUG_ERROR, "%a: Group Extension Response = 0x%x. Returning\n", __FUNCTION__, ResponseData.GroupExtensionId));
+      return EFI_DEVICE_ERROR;
+    } else {
+      if (BootstrapUsername != NULL) {
+        CopyMem (BootstrapUsername, ResponseData.Username, USERNAME_MAX_LENGTH);
+        //
+        // Manually append null-terminator in case 16 characters username returned.
+        //
+        BootstrapUsername[USERNAME_MAX_LENGTH] = '\0';
+      }
+
+      if (BootstrapPassword != NULL) {
+        CopyMem (BootstrapPassword, ResponseData.Password, PASSWORD_MAX_LENGTH);
+        //
+        // Manually append null-terminator in case 16 characters password returned.
+        //
+        BootstrapPassword[PASSWORD_MAX_LENGTH] = '\0';
+      }
+    }
+  }
+
+  DEBUG ((DEBUG_INFO, "%a: get bootstrap credential via IPMI: %r\n", 
+ __FUNCTION__, Status));
+
+  return Status;
+}
+
+/**
+  Function to retrieve temporary user credentials from cached boot time variable.
+
+  @param[in,out] BootstrapUsername    A pointer to a Ascii encoded string for the credential username
+  @param[in,out] BootstrapPassword    A pointer to a Ascii encoded string for the credential password
+
+  @retval  EFI_SUCCESS                Credentials were successfully fetched and returned
+  @retval  EFI_INVALID_PARAMETER      BootstrapUsername or BootstrapPassword is NULL
+  @retval  EFI_NOT_FOUND              No variable found for account and credentials
+**/
+EFI_STATUS
+GetBootstrapAccountCredentialsFromVariable (
+  IN OUT CHAR8  *BootstrapUsername,
+  IN OUT CHAR8  *BootstrapPassword
+  )
+{
+  EFI_STATUS                      Status;
+  BOOTSTRAP_CREDENTIALS_VARIABLE  *CredentialVariable;
+  VOID                            *Data;
+  UINTN                           DataSize;
+
+  if ((BootstrapUsername == NULL) || (BootstrapPassword == NULL)) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  DataSize = 0;
+  Status   = GetVariable2 (
+               CREDENTIAL_VARIABLE_NAME,
+               &gEfiRedfishVariableGuid,
+               (VOID *)&Data,
+               &DataSize
+               );
+  if (EFI_ERROR (Status)) {
+    return EFI_NOT_FOUND;
+  }
+
+  if (DataSize != sizeof (BOOTSTRAP_CREDENTIALS_VARIABLE)) {
+    DEBUG ((DEBUG_ERROR, "%a: data corruption. returned size: %d != structure size: %d\n", __FUNCTION__, DataSize, sizeof (BOOTSTRAP_CREDENTIALS_VARIABLE)));
+    return EFI_NOT_FOUND;
+  }
+
+  CredentialVariable = (BOOTSTRAP_CREDENTIALS_VARIABLE *)Data;
+
+  AsciiStrCpyS (BootstrapUsername, USERNAME_MAX_SIZE, 
+ CredentialVariable->Username);  AsciiStrCpyS (BootstrapPassword, 
+ PASSWORD_MAX_SIZE, CredentialVariable->Password);
+
+  ZeroMem (CredentialVariable->Username, USERNAME_MAX_SIZE);  ZeroMem 
+ (CredentialVariable->Password, PASSWORD_MAX_SIZE);
+
+  FreePool (Data);
+
+  DEBUG ((DEBUG_INFO, "%a: get bootstrap credential from variable\n", 
+ __FUNCTION__));
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Function to save temporary user credentials into boot time variable. 
+When DeleteVariable is True,
+  this function delete boot time variable.
+
+  @param[in] BootstrapUsername       A pointer to a Ascii encoded string for the credential username.
+  @param[in] BootstrapPassword       A pointer to a Ascii encoded string for the credential password.
+  @param[in] DeleteVariable          True to remove boot time variable. False otherwise.
+
+  @retval  EFI_SUCCESS                Credentials were successfully saved.
+  @retval  EFI_INVALID_PARAMETER      BootstrapUsername or BootstrapPassword is NULL
+  @retval  Others                     Error occurs
+**/
+EFI_STATUS
+SetBootstrapAccountCredentialsToVariable (
+  IN CHAR8 *BootstrapUsername, OPTIONAL
+  IN CHAR8  *BootstrapPassword, OPTIONAL
+  IN BOOLEAN DeleteVariable
+  )
+{
+  EFI_STATUS                      Status;
+  BOOTSTRAP_CREDENTIALS_VARIABLE  CredentialVariable;
+  VOID                            *Data;
+
+  if (!DeleteVariable && ((BootstrapUsername == NULL) || (BootstrapUsername[0] == '\0'))) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  if (!DeleteVariable && ((BootstrapPassword == NULL) || (BootstrapPassword[0] == '\0'))) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // Delete variable
+  //
+  if (DeleteVariable) {
+    Status = GetVariable2 (
+               CREDENTIAL_VARIABLE_NAME,
+               &gEfiRedfishVariableGuid,
+               (VOID *)&Data,
+               NULL
+               );
+    if (!EFI_ERROR (Status)) {
+      FreePool (Data);
+      gRT->SetVariable (CREDENTIAL_VARIABLE_NAME, &gEfiRedfishVariableGuid, EFI_VARIABLE_BOOTSERVICE_ACCESS, 0, NULL);
+    }
+
+    return EFI_SUCCESS;
+  }
+
+  ZeroMem (CredentialVariable.Username, USERNAME_MAX_SIZE);  ZeroMem 
+ (CredentialVariable.Password, PASSWORD_MAX_SIZE);
+
+  AsciiStrCpyS (CredentialVariable.Username, USERNAME_MAX_SIZE, 
+ BootstrapUsername);  AsciiStrCpyS (CredentialVariable.Password, 
+ PASSWORD_MAX_SIZE, BootstrapPassword);
+
+  //
+  // Check if variable exists already. If yes, remove it first.
+  //
+  Status = GetVariable2 (
+             CREDENTIAL_VARIABLE_NAME,
+             &gEfiRedfishVariableGuid,
+             (VOID *)&Data,
+             NULL
+             );
+  if (!EFI_ERROR (Status)) {
+    FreePool (Data);
+    gRT->SetVariable (CREDENTIAL_VARIABLE_NAME, 
+ &gEfiRedfishVariableGuid, EFI_VARIABLE_BOOTSERVICE_ACCESS, 0, NULL);  
+ }
+
+  Status = gRT->SetVariable (CREDENTIAL_VARIABLE_NAME, 
+ &gEfiRedfishVariableGuid, EFI_VARIABLE_BOOTSERVICE_ACCESS, sizeof 
+ (BOOTSTRAP_CREDENTIALS_VARIABLE), (VOID *)&CredentialVariable);
+

You used the same operations to delete NVRAM variable in two places.
What if we delete it at the beginning and then just return from the function if DeleteVariable is TRUE.

Something like this:


  //
  // Delete variable
  //
  Status = GetVariable2 (
             CREDENTIAL_VARIABLE_NAME,
             &gEfiRedfishVariableGuid,
             (VOID *)&Data,
             NULL
             );
  if (!EFI_ERROR (Status)) {
    FreePool (Data);
    gRT->SetVariable (CREDENTIAL_VARIABLE_NAME, &gEfiRedfishVariableGuid, EFI_VARIABLE_BOOTSERVICE_ACCESS, 0, NULL);
  }

  if (DeleteVariable) {
    return EFI_SUCCESS;
  }

  ZeroMem (CredentialVariable.Username, USERNAME_MAX_SIZE);
  ZeroMem (CredentialVariable.Password, PASSWORD_MAX_SIZE);

  AsciiStrCpyS (CredentialVariable.Username, USERNAME_MAX_SIZE, BootstrapUsername);
  AsciiStrCpyS (CredentialVariable.Password, PASSWORD_MAX_SIZE, BootstrapPassword);

  Status = gRT->SetVariable (CREDENTIAL_VARIABLE_NAME, &gEfiRedfishVariableGuid, EFI_VARIABLE_BOOTSERVICE_ACCESS, sizeof (BOOTSTRAP_CREDENTIALS_VARIABLE), (VOID *)&CredentialVariable);

Just small optimization of the code.

+  ZeroMem (CredentialVariable.Username, USERNAME_MAX_SIZE);  ZeroMem 
+ (CredentialVariable.Password, PASSWORD_MAX_SIZE);
+
+  return Status;
+}
+
+/**
+  Retrieve platform's Redfish authentication information.
+
+  This functions returns the Redfish authentication method together 
+ with the user Id and  password.
+  - For AuthMethodNone, the UserId and Password could be used for HTTP header authentication
+    as defined by RFC7235.
+  - For AuthMethodRedfishSession, the UserId and Password could be used for Redfish
+    session login as defined by  Redfish API specification (DSP0266).
+
+  Callers are responsible for and freeing the returned string storage.
+
+  @param[in]   This                Pointer to EDKII_REDFISH_CREDENTIAL_PROTOCOL instance.
+  @param[out]  AuthMethod          Type of Redfish authentication method.
+  @param[out]  UserId              The pointer to store the returned UserId string.
+  @param[out]  Password            The pointer to store the returned Password string.
+
+  @retval EFI_SUCCESS              Get the authentication information successfully.
+  @retval EFI_ACCESS_DENIED        SecureBoot is disabled after EndOfDxe.
+  @retval EFI_INVALID_PARAMETER    This or AuthMethod or UserId or Password is NULL.
+  @retval EFI_OUT_OF_RESOURCES     There are not enough memory resources.
+  @retval EFI_UNSUPPORTED          Unsupported authentication method is found.
+
+**/
+EFI_STATUS
+EFIAPI
+LibCredentialGetAuthInfo (
+  IN  EDKII_REDFISH_CREDENTIAL_PROTOCOL  *This,
+  OUT EDKII_REDFISH_AUTH_METHOD          *AuthMethod,
+  OUT CHAR8                              **UserId,
+  OUT CHAR8                              **Password
+  )
+{
+  EFI_STATUS  Status;
+
+  if ((AuthMethod == NULL) || (UserId == NULL) || (Password == NULL)) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  *UserId   = NULL;
+  *Password = NULL;
+
+  if (mRedfishServiceStopped) {
+    DEBUG ((DEBUG_ERROR, "%a: credential service is stopped due to security reason\n", __FUNCTION__));
+    return EFI_ACCESS_DENIED;
+  }
+
+  *AuthMethod = AuthMethodHttpBasic;
+
+  *UserId = AllocateZeroPool (sizeof (CHAR8) * USERNAME_MAX_SIZE);  if 
+ (*UserId == NULL) {
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+  *Password = AllocateZeroPool (sizeof (CHAR8) * PASSWORD_MAX_SIZE);  
+ if (*Password == NULL) {
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+  //
+  // Get bootstrap credential from variable first  //  Status = 
+ GetBootstrapAccountCredentialsFromVariable (*UserId, *Password);  if 
+ (!EFI_ERROR (Status)) {
+    return EFI_SUCCESS;
+  }
+
+  //
+  // Make a IPMI query
+  //
+  Status = GetBootstrapAccountCredentials (FALSE, *UserId, *Password);  
+ if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_ERROR, "%a: fail to get bootstrap credential: %r\n", __FUNCTION__, Status));
+    return Status;
+  }
+
+  Status = SetBootstrapAccountCredentialsToVariable (*UserId, 
+ *Password, FALSE);  if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_ERROR, "%a: fail to cache bootstrap credential: 
+ %r\n", __FUNCTION__, Status));  }
+
+  return EFI_SUCCESS;
+}
diff --git a/RedfishPkg/Library/RedfishPlatformCredentialIpmi/RedfishPlatformCredentialIpmiLib.h b/RedfishPkg/Library/RedfishPlatformCredentialIpmi/RedfishPlatformCredentialIpmiLib.h
new file mode 100644
index 0000000000..5325767eab
--- /dev/null
+++ b/RedfishPkg/Library/RedfishPlatformCredentialIpmi/RedfishPlatformCr
+++ edentialIpmiLib.h
@@ -0,0 +1,86 @@
+/** @file
+  Header file for RedfishPlatformCredentialIpmiLib.
+
+  Copyright (c) 2022-2023 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef REDFISH_PLATFORM_CREDENTIAL_IPMI_LIB_H_
+#define REDFISH_PLATFORM_CREDENTIAL_IPMI_LIB_H_
+
+#include <Uefi.h>
+#include <IndustryStandard/Ipmi.h>
+#include <IndustryStandard/RedfishHostInterfaceIpmi.h>
+
+#include <Protocol/EdkIIRedfishCredential.h>
+
+#include <Library/BaseLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/DebugLib.h>
+#include <Library/IpmiLib.h>
+#include <Library/MemoryAllocationLib.h> #include 
+<Library/RedfishCredentialLib.h> #include <Library/UefiLib.h> #include 
+<Library/UefiRuntimeServicesTableLib.h>
+
+#define CREDENTIAL_VARIABLE_NAME  L"Partstooblaitnederc"
+
+///
+/// The bootstrap credential keeping in UEFI variable /// typedef 
+struct {
+  CHAR8    Username[USERNAME_MAX_SIZE];
+  CHAR8    Password[PASSWORD_MAX_SIZE];
+} BOOTSTRAP_CREDENTIALS_VARIABLE;
+
+/**
+  Function to retrieve temporary user credentials for the UEFI redfish 
+client. This function can
+  also disable bootstrap credential service in BMC.
+
+  @param[in]  DisableBootstrapControl
+                                      TRUE - Tell the BMC to disable the bootstrap credential
+                                             service to ensure no one else gains credentials
+                                      FALSE  Allow the bootstrap 
+ credential service to continue  @param[out] BootstrapUsername
+                                      A pointer to a Ascii encoded string for the credential username
+                                      When DisableBootstrapControl is 
+ TRUE, this pointer can be NULL
+
+  @param[out] BootstrapPassword
+                                      A pointer to a Ascii encoded string for the credential password
+                                      When DisableBootstrapControl is 
+ TRUE, this pointer can be NULL
+
+  @retval  EFI_SUCCESS                Credentials were successfully fetched and returned. When DisableBootstrapControl
+                                      is set to TRUE, the bootstrap credential service is disabled successfully.
+  @retval  EFI_INVALID_PARAMETER      BootstrapUsername or BootstrapPassword is NULL when DisableBootstrapControl
+                                      is set to FALSE
+  @retval  EFI_DEVICE_ERROR           An IPMI failure occurred
+**/
+EFI_STATUS
+GetBootstrapAccountCredentials (
+  IN BOOLEAN    DisableBootstrapControl,
+  IN OUT CHAR8  *BootstrapUsername,
+  IN OUT CHAR8  *BootstrapPassword
+  );

BootstrapUsername and BootstrapPassword buffers allocated in the external functions but filled in the GetBootstrapAccountCredentials. How do we know if the size of the buffer is enough to hold username and password.
Should we mention the required size in the description of the function.
Or we can send the size of the buffers as the parameters and check their sizes in the function. Return error in case the size is wrong.


+
+/**
+  Function to save temporary user credentials into boot time variable. 
+When DeleteVariable is True,
+  this function delete boot time variable.
+
+  @param[in] BootstrapUsername       A pointer to a Ascii encoded string for the credential username.
+  @param[in] BootstrapPassword       A pointer to a Ascii encoded string for the credential password.
+  @param[in] DeleteVariable          True to remove boot time variable. False otherwise.
+
+  @retval  EFI_SUCCESS                Credentials were successfully saved.
+  @retval  EFI_INVALID_PARAMETER      BootstrapUsername or BootstrapPassword is NULL
+  @retval  Others                     Error occurs
+**/
+EFI_STATUS
+SetBootstrapAccountCredentialsToVariable (
+  IN CHAR8 *BootstrapUsername, OPTIONAL
+  IN CHAR8  *BootstrapPassword, OPTIONAL
+  IN BOOLEAN DeleteVariable
+  );
+
+#endif
diff --git a/RedfishPkg/Library/RedfishPlatformCredentialIpmi/RedfishPlatformCredentialIpmiLib.inf b/RedfishPkg/Library/RedfishPlatformCredentialIpmi/RedfishPlatformCredentialIpmiLib.inf
new file mode 100644
index 0000000000..694e401ad9
--- /dev/null
+++ b/RedfishPkg/Library/RedfishPlatformCredentialIpmi/RedfishPlatformCr
+++ edentialIpmiLib.inf
@@ -0,0 +1,42 @@
+## @file
+#  INF file for RedfishPlatformCredentialIpmiLib.
+#
+#  Copyright (c) 2022-2023 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+#
+#  SPDX-License-Identifier: BSD-2-Clause-Patent # ##
+
+[Defines]
+  INF_VERSION                    = 0x0001000b
+  BASE_NAME                      = RedfishPlatformCredentialIpmiLib
+  FILE_GUID                      = 9C45D622-4C66-417F-814C-F76246D97233
+  MODULE_TYPE                    = DXE_DRIVER
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = RedfishPlatformCredentialIpmiLib
+
+[Sources]
+  RedfishPlatformCredentialIpmiLib.c
+  RedfishPlatformCredentialIpmiLib.h
+
+[Packages]
+  MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+  RedfishPkg/RedfishPkg.dec
+
+[LibraryClasses]
+  UefiLib
+  DebugLib
+  IpmiBaseLib
+  MemoryAllocationLib
+  BaseMemoryLib
+  UefiRuntimeServicesTableLib
+
+[Pcd]
+  
+gEfiRedfishPkgTokenSpaceGuid.PcdRedfishDisableBootstrapCredentialServic
+e
+
+[Guids]
+  gEfiRedfishVariableGuid
+
+[Depex]
+  TRUE
diff --git a/RedfishPkg/RedfishPkg.dec b/RedfishPkg/RedfishPkg.dec index 53e52c2b00..86102b8ffd 100644
--- a/RedfishPkg/RedfishPkg.dec
+++ b/RedfishPkg/RedfishPkg.dec
@@ -81,6 +81,9 @@
 [Guids]
   gEfiRedfishPkgTokenSpaceGuid      = { 0x4fdbccb7, 0xe829, 0x4b4c, { 0x88, 0x87, 0xb2, 0x3f, 0xd7, 0x25, 0x4b, 0x85 }}

+  # Redfish variable guid
+  gEfiRedfishVariableGuid           = { 0x85ef8dd3, 0xe606, 0x4b89, { 0x8b, 0xbd, 0x93, 0xbf, 0x5c, 0xbe, 0x1c, 0x18 } }
+
 [PcdsFixedAtBuild, PcdsPatchableInModule]
   #
   # This PCD is the UEFI device path which is used as the Redfish host interface.
@@ -113,3 +116,7 @@
   # Default is set to not add.
   #
   gEfiRedfishPkgTokenSpaceGuid.PcdRedfishRestExAddingExpect|FALSE|BOOLEAN|0x00001004
+  #
+  # This PCD indicates that if BMC bootstrap credential service will be disabled by BIOS or not.
+  #
+  
+ gEfiRedfishPkgTokenSpaceGuid.PcdRedfishDisableBootstrapCredentialServi
+ ce|FALSE|BOOLEAN|0x00001005
diff --git a/RedfishPkg/RedfishPkg.dsc b/RedfishPkg/RedfishPkg.dsc index cf25b63cc2..f2ca212bea 100644
--- a/RedfishPkg/RedfishPkg.dsc
+++ b/RedfishPkg/RedfishPkg.dsc
@@ -3,6 +3,7 @@
 #
 # Copyright (c) 2019 - 2021, Intel Corporation. All rights reserved.<BR>  # (C) Copyright 2021 Hewlett-Packard Enterprise Development LP.
+# Copyright (c) 2023, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
 #
 #    SPDX-License-Identifier: BSD-2-Clause-Patent
 #
@@ -52,6 +53,7 @@
 [Components]
   RedfishPkg/Library/PlatformHostInterfaceLibNull/PlatformHostInterfaceLibNull.inf
   RedfishPkg/Library/PlatformCredentialLibNull/PlatformCredentialLibNull.inf
+  
+ RedfishPkg/Library/RedfishPlatformCredentialIpmi/RedfishPlatformCreden
+ tialIpmiLib.inf
   RedfishPkg/Library/RedfishContentCodingLibNull/RedfishContentCodingLibNull.inf
   RedfishPkg/Library/DxeRestExLib/DxeRestExLib.inf
   RedfishPkg/Library/BaseUcs2Utf8Lib/BaseUcs2Utf8Lib.inf
--
2.39.2.windows.1

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