| /****************************************************************************** |
| * |
| * Module Name: utcksum - Support generating table checksums |
| * |
| *****************************************************************************/ |
| |
| /* |
| * Copyright (C) 2000 - 2023, Intel Corp. |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions, and the following disclaimer, |
| * without modification. |
| * 2. Redistributions in binary form must reproduce at minimum a disclaimer |
| * substantially similar to the "NO WARRANTY" disclaimer below |
| * ("Disclaimer") and any redistribution must be conditioned upon |
| * including a substantially similar Disclaimer requirement for further |
| * binary redistribution. |
| * 3. Neither the names of the above-listed copyright holders nor the names |
| * of any contributors may be used to endorse or promote products derived |
| * from this software without specific prior written permission. |
| * |
| * Alternatively, this software may be distributed under the terms of the |
| * GNU General Public License ("GPL") version 2 as published by the Free |
| * Software Foundation. |
| * |
| * NO WARRANTY |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
| * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING |
| * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| * POSSIBILITY OF SUCH DAMAGES. |
| */ |
| |
| #include "acpi.h" |
| #include "accommon.h" |
| #include "acdisasm.h" |
| #include "acutils.h" |
| |
| |
| /* This module used for application-level code only */ |
| |
| #define _COMPONENT ACPI_CA_DISASSEMBLER |
| ACPI_MODULE_NAME ("utcksum") |
| |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: AcpiUtVerifyChecksum |
| * |
| * PARAMETERS: Table - ACPI table to verify |
| * Length - Length of entire table |
| * |
| * RETURN: Status |
| * |
| * DESCRIPTION: Verifies that the table checksums to zero. Optionally returns |
| * exception on bad checksum. |
| * Note: We don't have to check for a CDAT here, since CDAT is |
| * not in the RSDT/XSDT, and the CDAT table is never installed |
| * via ACPICA. |
| * |
| ******************************************************************************/ |
| |
| ACPI_STATUS |
| AcpiUtVerifyChecksum ( |
| ACPI_TABLE_HEADER *Table, |
| UINT32 Length) |
| { |
| UINT8 Checksum; |
| |
| |
| /* |
| * FACS/S3PT: |
| * They are the odd tables, have no standard ACPI header and no checksum |
| */ |
| if (ACPI_COMPARE_NAMESEG (Table->Signature, ACPI_SIG_S3PT) || |
| ACPI_COMPARE_NAMESEG (Table->Signature, ACPI_SIG_FACS)) |
| { |
| return (AE_OK); |
| } |
| |
| /* Compute the checksum on the table */ |
| |
| Length = Table->Length; |
| Checksum = AcpiUtGenerateChecksum (ACPI_CAST_PTR (UINT8, Table), Length, Table->Checksum); |
| |
| /* Computed checksum matches table? */ |
| |
| if (Checksum != Table->Checksum) |
| { |
| ACPI_BIOS_WARNING ((AE_INFO, |
| "Incorrect checksum in table [%4.4s] - 0x%2.2X, " |
| "should be 0x%2.2X", |
| Table->Signature, Table->Checksum, |
| Table->Checksum - Checksum)); |
| |
| #if (ACPI_CHECKSUM_ABORT) |
| return (AE_BAD_CHECKSUM); |
| #endif |
| } |
| |
| return (AE_OK); |
| } |
| |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: AcpiUtVerifyCdatChecksum |
| * |
| * PARAMETERS: Table - CDAT ACPI table to verify |
| * Length - Length of entire table |
| * |
| * RETURN: Status |
| * |
| * DESCRIPTION: Verifies that the CDAT table checksums to zero. Optionally |
| * returns an exception on bad checksum. |
| * |
| ******************************************************************************/ |
| |
| ACPI_STATUS |
| AcpiUtVerifyCdatChecksum ( |
| ACPI_TABLE_CDAT *CdatTable, |
| UINT32 Length) |
| { |
| UINT8 Checksum; |
| |
| |
| /* Compute the checksum on the table */ |
| |
| Checksum = AcpiUtGenerateChecksum (ACPI_CAST_PTR (UINT8, CdatTable), |
| CdatTable->Length, CdatTable->Checksum); |
| |
| /* Computed checksum matches table? */ |
| |
| if (Checksum != CdatTable->Checksum) |
| { |
| ACPI_BIOS_WARNING ((AE_INFO, |
| "Incorrect checksum in table [%4.4s] - 0x%2.2X, " |
| "should be 0x%2.2X", |
| AcpiGbl_CDAT, CdatTable->Checksum, Checksum)); |
| |
| #if (ACPI_CHECKSUM_ABORT) |
| return (AE_BAD_CHECKSUM); |
| #endif |
| } |
| |
| CdatTable->Checksum = Checksum; |
| return (AE_OK); |
| } |
| |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: AcpiUtGenerateChecksum |
| * |
| * PARAMETERS: Table - Pointer to table to be checksummed |
| * Length - Length of the table |
| * OriginalChecksum - Value of the checksum field |
| * |
| * RETURN: 8 bit checksum of buffer |
| * |
| * DESCRIPTION: Computes an 8 bit checksum of the table. |
| * |
| ******************************************************************************/ |
| |
| UINT8 |
| AcpiUtGenerateChecksum ( |
| void *Table, |
| UINT32 Length, |
| UINT8 OriginalChecksum) |
| { |
| UINT8 Checksum; |
| |
| |
| /* Sum the entire table as-is */ |
| |
| Checksum = AcpiUtChecksum ((UINT8 *) Table, Length); |
| |
| /* Subtract off the existing checksum value in the table */ |
| |
| Checksum = (UINT8) (Checksum - OriginalChecksum); |
| |
| /* Compute and return the final checksum */ |
| |
| Checksum = (UINT8) (0 - Checksum); |
| return (Checksum); |
| } |
| |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: AcpiUtChecksum |
| * |
| * PARAMETERS: Buffer - Pointer to memory region to be checked |
| * Length - Length of this memory region |
| * |
| * RETURN: Checksum (UINT8) |
| * |
| * DESCRIPTION: Calculates circular checksum of memory region. |
| * |
| ******************************************************************************/ |
| |
| UINT8 |
| AcpiUtChecksum ( |
| UINT8 *Buffer, |
| UINT32 Length) |
| { |
| UINT8 Sum = 0; |
| UINT8 *End = Buffer + Length; |
| |
| |
| while (Buffer < End) |
| { |
| Sum = (UINT8) (Sum + *(Buffer++)); |
| } |
| |
| return (Sum); |
| } |
