common/ucode/ucode_utils.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include <sys/types.h>
#include <sys/ucode.h>
#ifdef  _KERNEL
#include <sys/systm.h>
#else
#include <strings.h>
#endif

/*
 * Refer to
 *  Intel 64 and IA-32 Architectures Software Developers's Manual
 *      Chapter 9.11 Microcode Update Facilities
 * for details.
 */

/*
 * Validates the microcode header.
 * Returns EM_OK on success, EM_HEADER on failure.
 */
ucode_errno_t
ucode_header_validate_intel(ucode_header_intel_t *uhp)
{
    uint32_t header_size, body_size, total_size;

    if (uhp == NULL)
        return (EM_HEADER);

    /*
     * The only header version number supported is 1.
     */
    if (uhp->uh_header_ver != 0x1)
        return (EM_HEADER);

    header_size = UCODE_HEADER_SIZE_INTEL;
    total_size = UCODE_TOTAL_SIZE_INTEL(uhp->uh_total_size);
    body_size = UCODE_BODY_SIZE_INTEL(uhp->uh_body_size);

    /*
     * The body size field of the microcode code header specifies the size
     * of the encrypted data section, its value must be a multiple of the
     * size of DWORD.  The total size field must be in multiples of 1K
     * bytes.
     */
    if ((body_size % sizeof (int)) ||
        (total_size < (header_size + body_size)) ||
        (total_size % UCODE_KB(1)))

        return (EM_HEADER);

    /*
     * Sanity check to avoid reading bogus files
     */
    if (total_size < UCODE_MIN_SIZE || total_size > UCODE_MAX_SIZE)
        return (EM_HEADER);

    /*
     * If there is extended signature table, total_size is the sum of
     *  header_size
     *  body_size
     *  sizeof (struct ucode_ext_table)
     *  n * sizeof (struct ucode_ext_sig)
     * where n is indicated by uet_count in struct ucode_ext_table.
     */
    if (total_size > (header_size + body_size)) {
        if ((total_size - body_size - header_size -
            UCODE_EXT_TABLE_SIZE_INTEL) % UCODE_EXT_SIG_SIZE_INTEL) {

            return (EM_HEADER);
        }
    }

    return (EM_OK);
}

/*
 * Returns checksum.
 */
uint32_t
ucode_checksum_intel(uint32_t sum, uint32_t size, uint8_t *code)
{
    int i;
    uint32_t *lcode = (uint32_t *)(intptr_t)code;

    i = size >> 2;
    while (i--)
        sum += lcode[i];

    return (sum);
}

ucode_errno_t
ucode_validate_amd(uint8_t *ucodep, int size)
{
    /* LINTED: pointer alignment */
    uint32_t *ptr = (uint32_t *)ucodep;
    uint32_t count;

    if (ucodep == NULL || size <= 0)
        return (EM_INVALIDARG);

    /* Magic Number: "AMD\0" */
    size -= 4;
    if (*ptr++ != 0x00414d44)
        return (EM_FILEFORMAT);

    /* equivalence table */
    size -= 4;
    if (*ptr++)
        return (EM_FILEFORMAT);

    size -= 4;
    if (((count = *ptr++) > size) || (count % 16))
        return (EM_FILEFORMAT);

    /* LINTED: pointer alignment */
    ptr = (uint32_t *)(((uint8_t *)ptr) + count);
    size -= count;

    while (size > 8) {
        /* microcode patch */
        size -= 4;
        if (*ptr++ != 1)
            return (EM_FILEFORMAT);

        size -= 4;
        if (((count = *ptr++) > size))
            return (EM_FILEFORMAT);

        /* LINTED: pointer alignment */
        ptr = (uint32_t *)(((uint8_t *)ptr) + count);
        size -= count;
    }

    if (size)
        return (EM_FILEFORMAT);

    return (EM_OK);
}

ucode_errno_t
ucode_validate_intel(uint8_t *ucodep, int size)
{
    uint32_t header_size = UCODE_HEADER_SIZE_INTEL;
    int remaining;

    if (ucodep == NULL || size <= 0)
        return (EM_INVALIDARG);

    for (remaining = size; remaining > 0; ) {
        uint32_t total_size, body_size, ext_size;
        ucode_header_intel_t *uhp;
        uint8_t *curbuf = &ucodep[size - remaining];
        ucode_errno_t rc;

        uhp = (ucode_header_intel_t *)(intptr_t)curbuf;

        if ((rc = ucode_header_validate_intel(uhp)) != EM_OK)
            return (rc);

        total_size = UCODE_TOTAL_SIZE_INTEL(uhp->uh_total_size);

        if (ucode_checksum_intel(0, total_size, curbuf))
            return (EM_CHECKSUM);

        body_size = UCODE_BODY_SIZE_INTEL(uhp->uh_body_size);
        ext_size = total_size - (header_size + body_size);

        if (ext_size > 0) {
            uint32_t i;

            if (ucode_checksum_intel(0, ext_size,
                &curbuf[header_size + body_size])) {
                return (EM_CHECKSUM);
            }

            ext_size -= UCODE_EXT_TABLE_SIZE_INTEL;
            for (i = 0; i < ext_size / UCODE_EXT_SIG_SIZE_INTEL;
                i++) {
                if (ucode_checksum_intel(0,
                    UCODE_EXT_SIG_SIZE_INTEL,
                    &curbuf[total_size - ext_size +
                    i * UCODE_EXT_SIG_SIZE_INTEL])) {

                    return (EM_CHECKSUM);
                }
            }
        }

        remaining -= total_size;
    }
    return (EM_OK);
}