nloader.c

/*
 * Copyright (c) 2010, Sherpya <sherpya@netfarm.it>, aCaB <acab@0xacab.net>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the copyright holders nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * 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 BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, 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 DAMAGE.
 */

#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <setjmp.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/stat.h>

#include "nt_structs.h"

MODULE(main)

static jmp_buf sigsegv_env;
static void sigsegv_handler(int signum)
{
    longjmp(sigsegv_env, 1);
}


int main (int argc, char **argv) {

    int fd;
    unsigned int i;
    WCHAR commandline[1024] = L"autochk.exe *";

    uint8_t *ptr, *exe;
    void *ep;
    struct stat st;
    RTL_USER_PROCESS_PARAMETERS *params;

    const char *executable = (argc > 1) ? argv[1] : "autochk.exe";

    fd = open(executable, O_RDONLY | O_BINARY);
    if(fd<0) {
	perror("open");
	return 1;
    }

    if(fstat(fd, &st)<0) {
	perror("fstat");
	return 1;
    }

    exe = malloc(st.st_size);
    if(read(fd, exe, st.st_size) != st.st_size) {
	perror("read");
	close(fd);
	free(exe);
	return 1;
    }

    close(fd);
    ep = setup_nloader(exe, st.st_size, &params, 0);
    free(exe);

    if (!ep) {
	fprintf(stderr, "setup_nloader failed\n");
	return 1;
    }

    ptr = (uint8_t *)(params+1);
    params->ImagePathName.Buffer = (WCHAR *) ptr;

    for (i = 0; i < strlen(executable); i++)
        params->ImagePathName.Buffer[i] = executable[i];

    params->ImagePathName.Length = i;
    params->ImagePathName.MaximumLength = i + 1;

    // autochk.exe cmdline arguments (guess)
    // refs:
    //  - http://www.infocellar.com/winxp/chkdsk-and-autochk.htm
    //  - http://windows-xp-dox.net/MS.Press-Microsoft.Windows.XP1/prkd_tro_rgwn.htm
    //  - http://support.microsoft.com/kb/218461
    //  - http://support.microsoft.com/kb/160963/EN-US/

    // autochk.exe [switches] volume | *
    // * = all volumes, it queries global directory
    //
    // -t           - unknown (w7)
    // -s           - silent execution (w7)
    // -p           - force check even if dirty bit is not set
    // -r           - locate and recover bad sectors, implies -p (untested)
    // -b           - re-evaluates bad clusters on the volume, implies -r (w7)
    // -x volume    - force dismount (untested), without arguments crashes
    // -lXX         - with some values like 10 prints info and log size of the volume (the value is mul by 1024)
    // -l:XX        - tries to set log size, always fails for me saying the size is too small or unable to adjust
    // -k:volume    - excludes volume from the check (does make sense when using *)
    // -m           - run chkdsk only if dirty bit is set (default ?)
    // -i           - Performs a less vigorous check of index entries
    // -i[:XX]      - XX = 0-50 - unknown
    // -c           - Skips the checking of cycles within the folder structure

    if (argc > 1)
    {
        int c = params->ImagePathName.Length;
        memcpy(commandline, params->ImagePathName.Buffer, params->ImagePathName.Length * sizeof(WCHAR));

        for (i = 2; i < (unsigned) argc; i++)
        {
            char *arg = argv[i];
            int dev = 0;
            commandline[c++] = L' ';
            if (!strncmp(arg, "/dev/", 4))
            {
                size_t len = sizeof(VOLUME_PREFIX) - sizeof(WCHAR);
                dev = 1;
                memcpy(&commandline[c], VOLUME_PREFIX, len);
                len /= sizeof(WCHAR);
                c += len;
            }

            while (*arg && (c < sizeof(commandline) - 1))
                commandline[c++] = *arg++;

            if (dev) commandline[c++] = L'}';
        }
        commandline[c++] = 0;
    }

    ptr += sizeof(WCHAR);
    memcpy(ptr, commandline, sizeof(commandline));
    params->CommandLine.Length = sizeof(commandline) - sizeof(WCHAR);
    params->CommandLine.MaximumLength = sizeof(commandline);
    params->CommandLine.Buffer = (WCHAR *) ptr;

    /******************************************************************************************************* CALL ENTRYPOINT */
    signal(SIGSEGV, sigsegv_handler);

    if (setjmp(sigsegv_env))
    {
        /* clean up console */
        fflush(stdout);
        fprintf(stderr, "Native program crashed\n");
        exit(1);
    }
    else
    {
        BPX();
        return to_ep(ep);
    }
}