mpxu/common/valid_srecord.c

	valid_srecord.c revision 03831d35f7499c87d51205817c93e9a8d42c4bae
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (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 2002 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

/*
 * valid_srecord.c: to get and check an S-record string from a file
 * (firmware image to be downloaded to the service processor)
 */

#include <stdio.h>
#include <string.h>

#include "adm.h"


static unsigned long
ADM_string_to_long(char *s, int chars)
{
    unsigned long val = 0;

    while (chars--) {
        val = val << 4;
        if ((*s >= '0') && (*s <= '9'))
            val += *s - '0';
        else if ((*s >= 'a') && (*s <= 'f'))
            val += *s - 'a' + 10;
        else if ((*s >= 'A') && (*s <= 'F'))
            val += *s - 'A' + 10;
        s++;
    }
    return (val);
}


int
ADM_Valid_srecord(FILE  *FilePtr)
{
    static char Line[ADM_LINE_SIZE];
    char        *CurrentChar;
    int     SrecordLength;
    int     Sum;


    if (fgets(Line, ADM_LINE_SIZE, FilePtr) == NULL)
        return (SREC_ERR_LINE_TOO_BIG);

    rewind(FilePtr);

    if (strlen(Line) < 4)
        return (SREC_ERR_LINE_TOO_SMALL);

    /* Check first two characters for validity */
    if ((Line[0] != 'S') || (Line[1] < '0') || (Line[1] > '9'))
        return (SREC_ERR_BAD_HEADER);

    /* Next check the length for validity */
    SrecordLength = ADM_string_to_long(Line+2, 2);
    if (SrecordLength > ((strlen(Line) - 4) / 2))
        return (SREC_ERR_WRONG_LENGTH);

    /* Check the checksum. */
    CurrentChar = &Line[2]; /* Skip s-record header */
    SrecordLength   += 1;       /* Include checksum */
    Sum     = 0;
    while (SrecordLength--) {
        Sum     += ADM_string_to_long(CurrentChar, 2);
        CurrentChar += 2;
    }

    if ((Sum & 0xFF) != 0xFF)
        return (SREC_ERR_BAD_CRC); /* checksum failed */
    else
        return (SREC_OK); /* checksum passed */
}