diff options
Diffstat (limited to 'src/common/gsignond-utils.c')
| -rw-r--r-- | src/common/gsignond-utils.c | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/src/common/gsignond-utils.c b/src/common/gsignond-utils.c new file mode 100644 index 0000000..98d4065 --- /dev/null +++ b/src/common/gsignond-utils.c @@ -0,0 +1,163 @@ +/* vi: set et sw=4 ts=4 cino=t0,(0: */ +/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * This file is part of gsignond + * + * Copyright (C) 2013 Intel Corporation. + * + * Contact: Jussi Laako <jussi.laako@linux.intel.com> + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA + * 02110-1301 USA + */ + +#include <stdio.h> +#include <string.h> +#include <fcntl.h> +#include <unistd.h> +#include <sys/stat.h> + +#include "gsignond/gsignond-utils.h" +#include "gsignond/gsignond-log.h" + + +static size_t pagesize = 0; + + +gboolean +gsignond_wipe_file (const gchar *filename) +{ + gboolean retval = FALSE; + int rngfd; + int wipefd; + size_t sizeleft; + size_t writesize; + ssize_t sizewritten; + struct stat filestat; + guint8 *wipebuf; + + if (!pagesize) { + long confval = sysconf (_SC_PAGE_SIZE); + if (confval <= 0) + return FALSE; + pagesize = (size_t) confval; + } + + rngfd = open ("/dev/urandom", O_RDONLY); + if (rngfd < 0) + return FALSE; + + wipefd = open (filename, O_WRONLY | O_SYNC); + if (wipefd < 0) + goto _rng_exit; + wipebuf = g_malloc (pagesize); + if (fstat (wipefd, &filestat)) + goto _wipe_exit; + + /* write all 1's */ + sizeleft = filestat.st_size; + memset (wipebuf, 0xff, pagesize); + while (sizeleft) { + writesize = (sizeleft < pagesize) ? sizeleft : pagesize; + sizewritten = write (wipefd, wipebuf, writesize); + if (sizewritten != (ssize_t) writesize) + goto _wipe_exit; + sizeleft -= sizewritten; + } + + if (lseek (wipefd, 0, SEEK_SET) == (off_t) -1) + goto _wipe_exit; + + /* write all 0's */ + sizeleft = filestat.st_size; + memset (wipebuf, 0x00, pagesize); + while (sizeleft) { + writesize = (sizeleft < pagesize) ? sizeleft : pagesize; + sizewritten = write (wipefd, wipebuf, writesize); + if (sizewritten != (ssize_t) writesize) + goto _wipe_exit; + sizeleft -= sizewritten; + } + + if (lseek (wipefd, 0, SEEK_SET) == (off_t) -1) + goto _wipe_exit; + + /* write random */ + sizeleft = filestat.st_size; + while (sizeleft) { + writesize = (sizeleft < pagesize) ? sizeleft : pagesize; + if (read (rngfd, wipebuf, writesize) != (ssize_t) writesize) + goto _wipe_exit; + sizewritten = write (wipefd, wipebuf, writesize); + if (sizewritten != (ssize_t) writesize) + goto _wipe_exit; + sizeleft -= sizewritten; + } + + /* don't leave traces of last pattern to the memory */ + memset (wipebuf, 0x00, pagesize); + + /* remove the file and set return value on success */ + if (unlink (filename) == 0) { + retval = TRUE; + DBG ("successfully wiped file %s", filename); + } + +_wipe_exit: + g_free (wipebuf); + close (wipefd); +_rng_exit: + close (rngfd); + return retval; +} + + +gboolean +gsignond_wipe_directory (const gchar *dirname) +{ + gboolean retval = FALSE; + gboolean wiperes; + const gchar *filename; + gchar *filepath; + GDir *dirctx; + struct stat stat_entry; + + DBG ("wipe directory %s", dirname); + dirctx = g_dir_open (dirname, 0, NULL); + if (!dirctx) + return FALSE; + while ((filename = g_dir_read_name (dirctx))) { + filepath = g_build_filename (dirname, filename, NULL); + if (lstat(filepath, &stat_entry)) + goto _dir_exit; + if (S_ISDIR (stat_entry.st_mode) || + S_ISLNK (stat_entry.st_mode)) { + DBG ("remove directory or link %s", filepath); + wiperes = (remove (filepath) == 0); + } else { + DBG ("wipe file %s", filepath); + wiperes = gsignond_wipe_file (filepath); + } + g_free (filepath); + if (!wiperes) + goto _dir_exit; + } + retval = TRUE; + +_dir_exit: + g_dir_close (dirctx); + return retval; +} + |