acpica/utilities/utcksum.c

0001 /******************************************************************************
0002  *
0003  * Module Name: utcksum - Support generating table checksums
0004  *
0005  *****************************************************************************/
0006
0007 /******************************************************************************
0008  *
0009  * 1. Copyright Notice
0010  *
0011  * Some or all of this work - Copyright (c) 1999 - 2024, Intel Corp.
0012  * All rights reserved.
0013  *
0014  * 2. License
0015  *
0016  * 2.1. This is your license from Intel Corp. under its intellectual property
0017  * rights. You may have additional license terms from the party that provided
0018  * you this software, covering your right to use that party's intellectual
0019  * property rights.
0020  *
0021  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
0022  * copy of the source code appearing in this file ("Covered Code") an
0023  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
0024  * base code distributed originally by Intel ("Original Intel Code") to copy,
0025  * make derivatives, distribute, use and display any portion of the Covered
0026  * Code in any form, with the right to sublicense such rights; and
0027  *
0028  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
0029  * license (with the right to sublicense), under only those claims of Intel
0030  * patents that are infringed by the Original Intel Code, to make, use, sell,
0031  * offer to sell, and import the Covered Code and derivative works thereof
0032  * solely to the minimum extent necessary to exercise the above copyright
0033  * license, and in no event shall the patent license extend to any additions
0034  * to or modifications of the Original Intel Code. No other license or right
0035  * is granted directly or by implication, estoppel or otherwise;
0036  *
0037  * The above copyright and patent license is granted only if the following
0038  * conditions are met:
0039  *
0040  * 3. Conditions
0041  *
0042  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
0043  * Redistribution of source code of any substantial portion of the Covered
0044  * Code or modification with rights to further distribute source must include
0045  * the above Copyright Notice, the above License, this list of Conditions,
0046  * and the following Disclaimer and Export Compliance provision. In addition,
0047  * Licensee must cause all Covered Code to which Licensee contributes to
0048  * contain a file documenting the changes Licensee made to create that Covered
0049  * Code and the date of any change. Licensee must include in that file the
0050  * documentation of any changes made by any predecessor Licensee. Licensee
0051  * must include a prominent statement that the modification is derived,
0052  * directly or indirectly, from Original Intel Code.
0053  *
0054  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
0055  * Redistribution of source code of any substantial portion of the Covered
0056  * Code or modification without rights to further distribute source must
0057  * include the following Disclaimer and Export Compliance provision in the
0058  * documentation and/or other materials provided with distribution. In
0059  * addition, Licensee may not authorize further sublicense of source of any
0060  * portion of the Covered Code, and must include terms to the effect that the
0061  * license from Licensee to its licensee is limited to the intellectual
0062  * property embodied in the software Licensee provides to its licensee, and
0063  * not to intellectual property embodied in modifications its licensee may
0064  * make.
0065  *
0066  * 3.3. Redistribution of Executable. Redistribution in executable form of any
0067  * substantial portion of the Covered Code or modification must reproduce the
0068  * above Copyright Notice, and the following Disclaimer and Export Compliance
0069  * provision in the documentation and/or other materials provided with the
0070  * distribution.
0071  *
0072  * 3.4. Intel retains all right, title, and interest in and to the Original
0073  * Intel Code.
0074  *
0075  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
0076  * Intel shall be used in advertising or otherwise to promote the sale, use or
0077  * other dealings in products derived from or relating to the Covered Code
0078  * without prior written authorization from Intel.
0079  *
0080  * 4. Disclaimer and Export Compliance
0081  *
0082  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
0083  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
0084  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
0085  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
0086  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
0087  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
0088  * PARTICULAR PURPOSE.
0089  *
0090  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
0091  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
0092  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
0093  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
0094  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
0095  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
0096  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
0097  * LIMITED REMEDY.
0098  *
0099  * 4.3. Licensee shall not export, either directly or indirectly, any of this
0100  * software or system incorporating such software without first obtaining any
0101  * required license or other approval from the U. S. Department of Commerce or
0102  * any other agency or department of the United States Government. In the
0103  * event Licensee exports any such software from the United States or
0104  * re-exports any such software from a foreign destination, Licensee shall
0105  * ensure that the distribution and export/re-export of the software is in
0106  * compliance with all laws, regulations, orders, or other restrictions of the
0107  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
0108  * any of its subsidiaries will export/re-export any technical data, process,
0109  * software, or service, directly or indirectly, to any country for which the
0110  * United States government or any agency thereof requires an export license,
0111  * other governmental approval, or letter of assurance, without first obtaining
0112  * such license, approval or letter.
0113  *
0114  *****************************************************************************
0115  *
0116  * Alternatively, you may choose to be licensed under the terms of the
0117  * following license:
0118  *
0119  * Redistribution and use in source and binary forms, with or without
0120  * modification, are permitted provided that the following conditions
0121  * are met:
0122  * 1. Redistributions of source code must retain the above copyright
0123  *    notice, this list of conditions, and the following disclaimer,
0124  *    without modification.
0125  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
0126  *    substantially similar to the "NO WARRANTY" disclaimer below
0127  *    ("Disclaimer") and any redistribution must be conditioned upon
0128  *    including a substantially similar Disclaimer requirement for further
0129  *    binary redistribution.
0130  * 3. Neither the names of the above-listed copyright holders nor the names
0131  *    of any contributors may be used to endorse or promote products derived
0132  *    from this software without specific prior written permission.
0133  *
0134  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
0135  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
0136  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
0137  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
0138  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
0139  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
0140  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
0141  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
0142  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
0143  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
0144  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
0145  *
0146  * Alternatively, you may choose to be licensed under the terms of the
0147  * GNU General Public License ("GPL") version 2 as published by the Free
0148  * Software Foundation.
0149  *
0150  *****************************************************************************/
0151
0152 #include "acpi.h"
0153 #include "accommon.h"
0154 #include "acdisasm.h"
0155 #include "acutils.h"
0156
0157
0158 /* This module used for application-level code only */
0159
0160 #define _COMPONENT          ACPI_CA_DISASSEMBLER
0161         ACPI_MODULE_NAME    ("utcksum")
0162
0163
0164 /*******************************************************************************
0165  *
0166  * FUNCTION:    AcpiUtVerifyChecksum
0167  *
0168  * PARAMETERS:  Table               - ACPI table to verify
0169  *              Length              - Length of entire table
0170  *
0171  * RETURN:      Status
0172  *
0173  * DESCRIPTION: Verifies that the table checksums to zero. Optionally returns
0174  *              exception on bad checksum.
0175  *              Note: We don't have to check for a CDAT here, since CDAT is
0176  *              not in the RSDT/XSDT, and the CDAT table is never installed
0177  *              via ACPICA.
0178  *
0179  ******************************************************************************/
0180
0181 ACPI_STATUS
0182 AcpiUtVerifyChecksum (
0183     ACPI_TABLE_HEADER       *Table,
0184     UINT32                  Length)
0185 {
0186     UINT8                   Checksum;
0187
0188
0189     /*
0190      * FACS/S3PT:
0191      * They are the odd tables, have no standard ACPI header and no checksum
0192      */
0193     if (ACPI_COMPARE_NAMESEG (Table->Signature, ACPI_SIG_S3PT) ||
0194         ACPI_COMPARE_NAMESEG (Table->Signature, ACPI_SIG_FACS))
0195     {
0196         return (AE_OK);
0197     }
0198
0199     /* Compute the checksum on the table */
0200
0201     Length = Table->Length;
0202     Checksum = AcpiUtGenerateChecksum (ACPI_CAST_PTR (UINT8, Table), Length, Table->Checksum);
0203
0204     /* Computed checksum matches table? */
0205
0206     if (Checksum != Table->Checksum)
0207     {
0208         ACPI_BIOS_WARNING ((AE_INFO,
0209             "Incorrect checksum in table [%4.4s] - 0x%2.2X, "
0210             "should be 0x%2.2X",
0211             Table->Signature, Table->Checksum,
0212             Table->Checksum - Checksum));
0213
0214 #if (ACPI_CHECKSUM_ABORT)
0215         return (AE_BAD_CHECKSUM);
0216 #endif
0217     }
0218
0219     return (AE_OK);
0220 }
0221
0222
0223 /*******************************************************************************
0224  *
0225  * FUNCTION:    AcpiUtVerifyCdatChecksum
0226  *
0227  * PARAMETERS:  Table               - CDAT ACPI table to verify
0228  *              Length              - Length of entire table
0229  *
0230  * RETURN:      Status
0231  *
0232  * DESCRIPTION: Verifies that the CDAT table checksums to zero. Optionally
0233  *              returns an exception on bad checksum.
0234  *
0235  ******************************************************************************/
0236
0237 ACPI_STATUS
0238 AcpiUtVerifyCdatChecksum (
0239     ACPI_TABLE_CDAT         *CdatTable,
0240     UINT32                  Length)
0241 {
0242     UINT8                   Checksum;
0243
0244
0245     /* Compute the checksum on the table */
0246
0247     Checksum = AcpiUtGenerateChecksum (ACPI_CAST_PTR (UINT8, CdatTable),
0248                     CdatTable->Length, CdatTable->Checksum);
0249
0250     /* Computed checksum matches table? */
0251
0252     if (Checksum != CdatTable->Checksum)
0253     {
0254         ACPI_BIOS_WARNING ((AE_INFO,
0255             "Incorrect checksum in table [%4.4s] - 0x%2.2X, "
0256             "should be 0x%2.2X",
0257             AcpiGbl_CDAT, CdatTable->Checksum, Checksum));
0258
0259 #if (ACPI_CHECKSUM_ABORT)
0260         return (AE_BAD_CHECKSUM);
0261 #endif
0262     }
0263
0264     CdatTable->Checksum = Checksum;
0265     return (AE_OK);
0266 }
0267
0268
0269 /*******************************************************************************
0270  *
0271  * FUNCTION:    AcpiUtGenerateChecksum
0272  *
0273  * PARAMETERS:  Table               - Pointer to table to be checksummed
0274  *              Length              - Length of the table
0275  *              OriginalChecksum    - Value of the checksum field
0276  *
0277  * RETURN:      8 bit checksum of buffer
0278  *
0279  * DESCRIPTION: Computes an 8 bit checksum of the table.
0280  *
0281  ******************************************************************************/
0282
0283 UINT8
0284 AcpiUtGenerateChecksum (
0285     void                    *Table,
0286     UINT32                  Length,
0287     UINT8                   OriginalChecksum)
0288 {
0289     UINT8                   Checksum;
0290
0291
0292     /* Sum the entire table as-is */
0293
0294     Checksum = AcpiUtChecksum ((UINT8 *) Table, Length);
0295
0296     /* Subtract off the existing checksum value in the table */
0297
0298     Checksum = (UINT8) (Checksum - OriginalChecksum);
0299
0300     /* Compute and return the final checksum */
0301
0302     Checksum = (UINT8) (0 - Checksum);
0303     return (Checksum);
0304 }
0305
0306
0307 /*******************************************************************************
0308  *
0309  * FUNCTION:    AcpiUtChecksum
0310  *
0311  * PARAMETERS:  Buffer          - Pointer to memory region to be checked
0312  *              Length          - Length of this memory region
0313  *
0314  * RETURN:      Checksum (UINT8)
0315  *
0316  * DESCRIPTION: Calculates circular checksum of memory region.
0317  *
0318  ******************************************************************************/
0319
0320 UINT8
0321 AcpiUtChecksum (
0322     UINT8                   *Buffer,
0323     UINT32                  Length)
0324 {
0325     UINT8                   Sum = 0;
0326     UINT8                   *End = Buffer + Length;
0327
0328
0329     while (Buffer < End)
0330     {
0331         Sum = (UINT8) (Sum + *(Buffer++));
0332     }
0333
0334     return (Sum);
0335 }