nwipe/src/device.c

/*
 *  device.c:  Device routines for nwipe.
 *
 *  Copyright Darik Horn <dajhorn-dban@vanadac.com>.
 *
 *  Modifications to original dwipe Copyright Andy Beverley <andy@andybev.com>
 *
 *  This program is free software; you can redistribute it and/or modify it under
 *  the terms of the GNU General Public License as published by the Free Software
 *  Foundation, version 2.
 *
 *  This program is distributed in the hope that it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 *  FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
 *  details.
 *
 *  You should have received a copy of the GNU General Public License along with
 *  this program; if not, write to the Free Software Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 */

#include <stdint.h>

#include "nwipe.h"
#include "context.h"
#include "method.h"
#include "options.h"
#include "logging.h"
#include <sys/ioctl.h>
#include <linux/hdreg.h>  // Drive specific defs
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <ctype.h>

#include <parted/parted.h>
#include <parted/debug.h>

int check_device( nwipe_context_t*** c, PedDevice* dev, int dcount );
char* trim( char* str );

int nwipe_device_scan( nwipe_context_t*** c )
{
    /**
     * Scans the filesystem for storage device names.
     *
     * @parameter device_names  A reference to a null array pointer.
     * @modifies  device_names  Populates device_names with an array of nwipe_contect_t
     * @returns                 The number of strings in the device_names array.
     *
     */

    PedDevice* dev = NULL;
    ped_device_probe_all();

    int dcount = 0;

    while( ( dev = ped_device_get_next( dev ) ) )
    {
        if( check_device( c, dev, dcount ) )
            dcount++;
    }

    /* Return the number of devices that were found. */
    return dcount;

} /* nwipe_device_scan */

int nwipe_device_get( nwipe_context_t*** c, char** devnamelist, int ndevnames )
{
    /**
     * Gets information about devices
     *
     * @parameter device_names  A reference to a null array pointer.
     * @parameter devnamelist   An array of string pointers to the device names
     * @parameter ndevnames     Number of elements in devnamelist
     * @modifies  device_names  Populates device_names with an array of nwipe_contect_t
     * @returns                 The number of strings in the device_names array.
     *
     */

    PedDevice* dev = NULL;

    int i;
    int dcount = 0;

    for( i = 0; i < ndevnames; i++ )
    {

        dev = ped_device_get( devnamelist[i] );
        if( !dev )
        {
            nwipe_log( NWIPE_LOG_WARNING, "Device %s not found", devnamelist[i] );
            continue;
        }

        if( check_device( c, dev, dcount ) )
            dcount++;
    }

    /* Return the number of devices that were found. */
    return dcount;

} /* nwipe_device_get */

int check_device( nwipe_context_t*** c, PedDevice* dev, int dcount )
{
    /* Populate this struct, then assign it to overall array of structs. */
    nwipe_context_t* next_device;
    int fd;
    int idx;

    /* Check whether this drive is on the excluded drive list ? */
    idx = 0;
    while( idx < 10 )
    {
        if( !strcmp( dev->path, nwipe_options.exclude[idx++] ) )
        {
            nwipe_log( NWIPE_LOG_NOTICE, "Device %s excluded as per command line option -e", dev->path );
            return 0;
        }
    }

    /* Try opening the device to see if it's valid. Close on completion. */
    if( !ped_device_open( dev ) )
    {
        nwipe_log( NWIPE_LOG_FATAL, "Unable to open device" );
        return 0;
    }
    ped_device_close( dev );

    /* New device, reallocate memory for additional struct pointer */
    *c = realloc( *c, ( dcount + 1 ) * sizeof( nwipe_context_t* ) );

    next_device = malloc( sizeof( nwipe_context_t ) );

    /* Check the allocation. */
    if( !next_device )
    {
        nwipe_perror( errno, __FUNCTION__, "malloc" );
        nwipe_log( NWIPE_LOG_FATAL, "Unable to create the array of enumeration contexts." );
        return 0;
    }

    /* Zero the allocation. */
    memset( next_device, 0, sizeof( nwipe_context_t ) );

    /* Get device information */
    next_device->device_model = dev->model;
    next_device->device_name = dev->path;
    next_device->device_size = dev->length * dev->sector_size;
    next_device->device_size_text = ped_unit_format_byte( dev, dev->length * dev->sector_size );
    next_device->result = -2;

    /* Attempt to get serial number of device. */
    if( ( fd = open( next_device->device_name = dev->path, O_RDONLY ) ) == ERR )
    {
        nwipe_log( NWIPE_LOG_WARNING, "Unable to open device %s to obtain serial number", next_device->device_name );
    }

    /*
     * We don't check the ioctl return status because there are plenty of situations where a serial number may not be
     * returned by ioctl such as USB drives, logical volumes, encryted volumes, so the log file would have multiple
     * benign ioctl errors reported which isn't necessarily a problem.
     */
    ioctl( fd, HDIO_GET_IDENTITY, &next_device->identity );
    close( fd );

    for( idx = 0; idx < 20; idx++ )
    {
        next_device->device_serial_no[idx] = next_device->identity.serial_no[idx];
    }

    // Terminate the string.
    next_device->device_serial_no[20] = 0;
    // Remove leading/trailing whitespace from serial number and left justify.
    trim( (char*) next_device->device_serial_no );

    if( strlen( (const char*) next_device->device_serial_no ) )
    {
        snprintf( next_device->device_label,
                  NWIPE_DEVICE_LABEL_LENGTH,
                  "%s (%s) - %s S/N:%s",
                  next_device->device_name,
                  next_device->device_size_text,
                  next_device->device_model,
                  next_device->device_serial_no );
    }
    else
    {
        snprintf( next_device->device_label,
                  NWIPE_DEVICE_LABEL_LENGTH,
                  "%s (%s) - %s",
                  next_device->device_name,
                  next_device->device_size_text,
                  next_device->device_model );
    }
    
        nwipe_log( NWIPE_LOG_NOTICE,
                 "Found %s, %s, %s, S/N=%s",
                  next_device->device_name,
                  next_device->device_model,
                  next_device->device_size_text,
                  next_device->device_serial_no );

    ( *c )[dcount] = next_device;
    return 1;
}

/* Remove leading/training whitespace from a string and left justify result */
char* trim( char* str )
{
    size_t len = 0;
    char* frontp = str;
    char* endp = NULL;

    if( str == NULL )
    {
        return NULL;
    }
    if( str[0] == '\0' )
    {
        return str;
    }
    len = strlen( str );
    endp = str + len;

    /*
     * Move the front and back pointers to address the first non-whitespace
     * characters from each end.
     */
    while( isspace( (unsigned char) *frontp ) )
    {
        ++frontp;
    }
    if( endp != frontp )
    {
        while( isspace( (unsigned char) *( --endp ) ) && endp != frontp )
        {
        }
    }
    if( str + len - 1 != endp )
        *( endp + 1 ) = '\0';
    else if( frontp != str && endp == frontp )
        *str = '\0';
    /*
     * Shift the string so that it starts at str so that if it's dynamically
     * allocated, we can still free it on the returned pointer.  Note the reuse
     * of endp to mean the front of the string buffer now.
     */
    endp = str;
    if( frontp != str )
    {
        while( *frontp )
        {
            *endp++ = *frontp++;
        }
        *endp = '\0';
    }
    return str;
}