X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=lib%2Futils.c;h=7e850a61419f56fb1bf75508bcd83b3418f73479;hb=690c363eb90277fc53a97e3e2367ebe12055937e;hp=e1d0e4a5582f9952695996ece800f0fd9772f1c5;hpb=dfe77be7480825fd4d42ac9eb11ef67e60780831;p=platform%2Fupstream%2Fcryptsetup.git

diff --git a/lib/utils.c b/lib/utils.c
index e1d0e4a..7e850a6 100644
--- a/lib/utils.c
+++ b/lib/utils.c
@@ -1,458 +1,345 @@
+/*
+ * utils - miscellaneous device utilities for cryptsetup
+ *
+ * Copyright (C) 2004 Jana Saout <jana@saout.de>
+ * Copyright (C) 2004-2007 Clemens Fruhwirth <clemens@endorphin.org>
+ * Copyright (C) 2009-2021 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2009-2021 Milan Broz
+ *
+ * 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; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * 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 <stdio.h>
-#include <string.h>
-#include <stdlib.h>
-#include <stddef.h>
-#include <stdarg.h>
 #include <errno.h>
-#include <linux/fs.h>
-#include <sys/types.h>
-#include <unistd.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <sys/ioctl.h>
-#include <fcntl.h>
 #include <sys/mman.h>
 #include <sys/resource.h>
+#include <sys/stat.h>
+#include <sys/utsname.h>
 
-#include "libcryptsetup.h"
 #include "internal.h"
 
-static char *error=NULL;
-
-void set_error_va(const char *fmt, va_list va)
-{
-	int r;
-
-	if(error) {
-		free(error);
-		error = NULL;
-	}
-
-	if(!fmt) return;
-
-	r = vasprintf(&error, fmt, va);
-	if (r < 0) {
-		free(error);
-		error = NULL;
-		return;
-	}
-
-	if (r && error[r - 1] == '\n')
-		error[r - 1] = '\0';
-}
-
-void set_error(const char *fmt, ...)
-{
-	va_list va;
-
-	va_start(va, fmt);
-	set_error_va(fmt, va);
-	va_end(va);
-}
-
-const char *get_error(void)
+size_t crypt_getpagesize(void)
 {
-	return error;
+	long r = sysconf(_SC_PAGESIZE);
+	return r <= 0 ? DEFAULT_MEM_ALIGNMENT : (size_t)r;
 }
 
-static int get_alignment(int fd)
+unsigned crypt_cpusonline(void)
 {
-	int alignment = DEFAULT_MEM_ALIGNMENT;
-
-#ifdef _PC_REC_XFER_ALIGN
-	alignment = fpathconf(fd, _PC_REC_XFER_ALIGN);
-	if (alignment < 0)
-		alignment = DEFAULT_MEM_ALIGNMENT;
-#endif
-	return alignment;
+	long r = sysconf(_SC_NPROCESSORS_ONLN);
+	return r < 0 ? 1 : r;
 }
 
-static void *aligned_malloc(void **base, int size, int alignment)
+uint64_t crypt_getphysmemory_kb(void)
 {
-#ifdef HAVE_POSIX_MEMALIGN
-	return posix_memalign(base, alignment, size) ? NULL : *base;
-#else
-/* Credits go to Michal's padlock patches for this alignment code */
-	char *ptr;
-
-	ptr  = malloc(size + alignment);
-	if(ptr == NULL) return NULL;
-
-	*base = ptr;
-	if(alignment > 1 && ((long)ptr & (alignment - 1))) {
-		ptr += alignment - ((long)(ptr) & (alignment - 1));
-	}
-	return ptr;
-#endif
-}
-static int sector_size(int fd) 
-{
-	int bsize;
-	if (ioctl(fd,BLKSSZGET, &bsize) < 0)
-		return -EINVAL;
-	else
-		return bsize;
-}
+	long pagesize, phys_pages;
+	uint64_t phys_memory_kb;
 
-int sector_size_for_device(const char *device)
-{
-	int fd = open(device, O_RDONLY);
-	int r;
-	if(fd < 0)
-		return -EINVAL;
-	r = sector_size(fd);
-	close(fd);
-	return r;
-}
+	pagesize = sysconf(_SC_PAGESIZE);
+	phys_pages = sysconf(_SC_PHYS_PAGES);
 
-ssize_t write_blockwise(int fd, const void *orig_buf, size_t count)
-{
-	void *hangover_buf, *hangover_buf_base = NULL;
-	void *buf, *buf_base = NULL;
-	int r, hangover, solid, bsize, alignment;
-	ssize_t ret = -1;
-
-	if ((bsize = sector_size(fd)) < 0)
-		return bsize;
-
-	hangover = count % bsize;
-	solid = count - hangover;
-	alignment = get_alignment(fd);
-
-	if ((long)orig_buf & (alignment - 1)) {
-		buf = aligned_malloc(&buf_base, count, alignment);
-		if (!buf)
-			goto out;
-		memcpy(buf, orig_buf, count);
-	} else
-		buf = (void *)orig_buf;
+	if (pagesize < 0 || phys_pages < 0)
+		return 0;
 
-	r = write(fd, buf, solid);
-	if (r < 0 || r != solid)
-		goto out;
+	phys_memory_kb = pagesize / 1024;
+	phys_memory_kb *= phys_pages;
 
-	if (hangover) {
-		hangover_buf = aligned_malloc(&hangover_buf_base, bsize, alignment);
-		if (!hangover_buf)
-			goto out;
+	return phys_memory_kb;
+}
 
-		r = read(fd, hangover_buf, bsize);
-		if(r < 0 || r != bsize) goto out;
+/* MEMLOCK */
+#define DEFAULT_PROCESS_PRIORITY -18
 
-		r = lseek(fd, -bsize, SEEK_CUR);
-		if (r < 0)
-			goto out;
-		memcpy(hangover_buf, buf + solid, hangover);
+static int _priority;
+static int _memlock_count = 0;
 
-		r = write(fd, hangover_buf, bsize);
-		if(r < 0 || r != bsize) goto out;
-		free(hangover_buf_base);
+// return 1 if memory is locked
+int crypt_memlock_inc(struct crypt_device *ctx)
+{
+	if (!_memlock_count++) {
+		log_dbg(ctx, "Locking memory.");
+		if (mlockall(MCL_CURRENT | MCL_FUTURE) == -1) {
+			log_dbg(ctx, "Cannot lock memory with mlockall.");
+			_memlock_count--;
+			return 0;
+		}
+		errno = 0;
+		if (((_priority = getpriority(PRIO_PROCESS, 0)) == -1) && errno)
+			log_err(ctx, _("Cannot get process priority."));
+		else
+			if (setpriority(PRIO_PROCESS, 0, DEFAULT_PROCESS_PRIORITY))
+				log_dbg(ctx, "setpriority %d failed: %s",
+					DEFAULT_PROCESS_PRIORITY, strerror(errno));
 	}
-	ret = count;
- out:
-	if (buf != orig_buf)
-		free(buf_base);
-	return ret;
+	return _memlock_count ? 1 : 0;
 }
 
-ssize_t read_blockwise(int fd, void *orig_buf, size_t count) {
-	void *hangover_buf, *hangover_buf_base;
-	void *buf, *buf_base = NULL;
-	int r, hangover, solid, bsize, alignment;
-	ssize_t ret = -1;
-
-	if ((bsize = sector_size(fd)) < 0)
-		return bsize;
-
-	hangover = count % bsize;
-	solid = count - hangover;
-	alignment = get_alignment(fd);
-
-	if ((long)orig_buf & (alignment - 1)) {
-		buf = aligned_malloc(&buf_base, count, alignment);
-		if (!buf)
-			goto out;
-	} else
-		buf = orig_buf;
-
-	r = read(fd, buf, solid);
-	if(r < 0 || r != solid)
-		goto out;
-
-	if (hangover) {
-		hangover_buf = aligned_malloc(&hangover_buf_base, bsize, alignment);
-		if (!hangover_buf)
-			goto out;
-		r = read(fd, hangover_buf, bsize);
-		if (r <  0 || r != bsize)
-			goto out;
-
-		memcpy(buf + solid, hangover_buf, hangover);
-		free(hangover_buf_base);
-	}
-	ret = count;
- out:
-	if (buf != orig_buf) {
-		memcpy(orig_buf, buf, count);
-		free(buf_base);
+int crypt_memlock_dec(struct crypt_device *ctx)
+{
+	if (_memlock_count && (!--_memlock_count)) {
+		log_dbg(ctx, "Unlocking memory.");
+		if (munlockall() == -1)
+			log_err(ctx, _("Cannot unlock memory."));
+		if (setpriority(PRIO_PROCESS, 0, _priority))
+			log_dbg(ctx, "setpriority %d failed: %s", _priority, strerror(errno));
 	}
-	return ret;
+	return _memlock_count ? 1 : 0;
 }
 
-/* 
- * Combines llseek with blockwise write. write_blockwise can already deal with short writes
- * but we also need a function to deal with short writes at the start. But this information
- * is implicitly included in the read/write offset, which can not be set to non-aligned 
- * boundaries. Hence, we combine llseek with write.
+/* Keyfile processing */
+
+/*
+ * A simple call to lseek(3) might not be possible for some inputs (e.g.
+ * reading from a pipe), so this function instead reads of up to BUFSIZ bytes
+ * at a time until the specified number of bytes. It returns -1 on read error
+ * or when it reaches EOF before the requested number of bytes have been
+ * discarded.
  */
+static int keyfile_seek(int fd, uint64_t bytes)
+{
+	char tmp[BUFSIZ];
+	size_t next_read;
+	ssize_t bytes_r;
+	off64_t r;
 
-ssize_t write_lseek_blockwise(int fd, const char *buf, size_t count, off_t offset) {
-	int bsize = sector_size(fd);
-	const char *orig_buf = buf;
-	char frontPadBuf[bsize];
-	int frontHang = offset % bsize;
-	int r;
-	int innerCount = count < bsize ? count : bsize;
+	r = lseek64(fd, bytes, SEEK_CUR);
+	if (r > 0)
+		return 0;
+	if (r < 0 && errno != ESPIPE)
+		return -1;
 
-	if (bsize < 0)
-		return bsize;
+	while (bytes > 0) {
+		/* figure out how much to read */
+		next_read = bytes > sizeof(tmp) ? sizeof(tmp) : (size_t)bytes;
 
-	lseek(fd, offset - frontHang, SEEK_SET);
-	if(offset % bsize) {
-		r = read(fd,frontPadBuf,bsize);
-		if(r < 0) return -1;
+		bytes_r = read(fd, tmp, next_read);
+		if (bytes_r < 0) {
+			if (errno == EINTR)
+				continue;
 
-		memcpy(frontPadBuf+frontHang, buf, innerCount);
+			crypt_safe_memzero(tmp, sizeof(tmp));
+			/* read error */
+			return -1;
+		}
 
-		lseek(fd, offset - frontHang, SEEK_SET);
-		r = write(fd,frontPadBuf,bsize);
-		if(r < 0) return -1;
+		if (bytes_r == 0)
+			/* EOF */
+			break;
 
-		buf += innerCount;
-		count -= innerCount;
+		bytes -= bytes_r;
 	}
-	if(count <= 0) return buf - orig_buf;
 
-	return write_blockwise(fd, buf, count) + innerCount;
+	crypt_safe_memzero(tmp, sizeof(tmp));
+	return bytes == 0 ? 0 : -1;
 }
 
-int device_ready(struct crypt_device *cd, const char *device, int mode)
+int crypt_keyfile_device_read(struct crypt_device *cd,  const char *keyfile,
+			      char **key, size_t *key_size_read,
+			      uint64_t keyfile_offset, size_t key_size,
+			      uint32_t flags)
 {
-	int devfd, r = 1;
-	ssize_t s;
+	int fd, regular_file, char_to_read = 0, char_read = 0, unlimited_read = 0;
+	int r = -EINVAL, newline;
+	char *pass = NULL;
+	size_t buflen, i;
+	uint64_t file_read_size;
 	struct stat st;
-	char buf[512];
 
-	if(stat(device, &st) < 0) {
-		log_err(cd, _("Device %s doesn't exist or access denied.\n"), device);
-		return 0;
-	}
+	if (!key || !key_size_read)
+		return -EINVAL;
 
-	log_dbg("Trying to open and read device %s.", device);
-	devfd = open(device, mode | O_DIRECT | O_SYNC);
-	if(devfd < 0) {
-		log_err(cd, _("Cannot open device %s for %s%s access.\n"), device,
-			(mode & O_EXCL) ? _("exclusive ") : "",
-			(mode & O_RDWR) ? _("writable") : _("read-only"));
-		return 0;
-	}
+	*key = NULL;
+	*key_size_read = 0;
 
-	 /* Try to read first sector */
-	s = read_blockwise(devfd, buf, sizeof(buf));
-	if (s < 0 || s != sizeof(buf)) {
-		log_err(cd, _("Cannot read device %s.\n"), device);
-		r = 0;
+	fd = keyfile ? open(keyfile, O_RDONLY) : STDIN_FILENO;
+	if (fd < 0) {
+		log_err(cd, _("Failed to open key file."));
+		return -EINVAL;
 	}
 
-	memset(buf, 0, sizeof(buf));
-	close(devfd);
+	if (isatty(fd)) {
+		log_err(cd, _("Cannot read keyfile from a terminal."));
+		r = -EINVAL;
+		goto out_err;
+	}
 
-	return r;
-}
+	/* If not requested otherwise, we limit input to prevent memory exhaustion */
+	if (key_size == 0) {
+		key_size = DEFAULT_KEYFILE_SIZE_MAXKB * 1024 + 1;
+		unlimited_read = 1;
+		/* use 4k for buffer (page divisor but avoid huge pages) */
+		buflen = 4096 - sizeof(size_t); // sizeof(struct safe_allocation);
+	} else
+		buflen = key_size;
 
-int get_device_infos(const char *device, struct device_infos *infos, struct crypt_device *cd)
-{
-	uint64_t size;
-	unsigned long size_small;
-	int readonly = 0;
-	int ret = -1;
-	int fd;
-
-	/* Try to open read-write to check whether it is a read-only device */
-	fd = open(device, O_RDWR);
-	if (fd < 0) {
-		if (errno == EROFS) {
-			readonly = 1;
-			fd = open(device, O_RDONLY);
+	regular_file = 0;
+	if (keyfile) {
+		if (stat(keyfile, &st) < 0) {
+			log_err(cd, _("Failed to stat key file."));
+			goto out_err;
+		}
+		if (S_ISREG(st.st_mode)) {
+			regular_file = 1;
+			file_read_size = (uint64_t)st.st_size;
+
+			if (keyfile_offset > file_read_size) {
+				log_err(cd, _("Cannot seek to requested keyfile offset."));
+				goto out_err;
+			}
+			file_read_size -= keyfile_offset;
+
+			/* known keyfile size, alloc it in one step */
+			if (file_read_size >= (uint64_t)key_size)
+				buflen = key_size;
+			else if (file_read_size)
+				buflen = file_read_size;
 		}
-	} else {
-		close(fd);
-		fd = open(device, O_RDONLY);
-	}
-	if (fd < 0) {
-		log_err(cd, _("Cannot open device: %s\n"), device);
-		return -1;
 	}
 
-#ifdef BLKROGET
-	/* If the device can be opened read-write, i.e. readonly is still 0, then
-	 * check whether BKROGET says that it is read-only. E.g. read-only loop
-	 * devices may be openend read-write but are read-only according to BLKROGET
-	 */
-	if (readonly == 0 && ioctl(fd, BLKROGET, &readonly) < 0) {
-		log_err(cd, _("BLKROGET failed on device %s.\n"), device);
-		goto out;
-	}
-#else
-#error BLKROGET not available
-#endif
-
-#ifdef BLKGETSIZE64
-	if (ioctl(fd, BLKGETSIZE64, &size) >= 0) {
-		size >>= SECTOR_SHIFT;
-		ret = 0;
-		goto out;
+	pass = crypt_safe_alloc(buflen);
+	if (!pass) {
+		log_err(cd, _("Out of memory while reading passphrase."));
+		goto out_err;
 	}
-#endif
 
-#ifdef BLKGETSIZE
-	if (ioctl(fd, BLKGETSIZE, &size_small) >= 0) {
-		size = (uint64_t)size_small;
-		ret = 0;
-		goto out;
+	/* Discard keyfile_offset bytes on input */
+	if (keyfile_offset && keyfile_seek(fd, keyfile_offset) < 0) {
+		log_err(cd, _("Cannot seek to requested keyfile offset."));
+		goto out_err;
 	}
-#else
-#	error Need at least the BLKGETSIZE ioctl!
-#endif
-
-	log_err(cd, _("BLKGETSIZE failed on device %s.\n"), device);
-out:
-	if (ret == 0) {
-		infos->size = size;
-		infos->readonly = readonly;
-	}
-	close(fd);
-	return ret;
-}
 
-int wipe_device_header(const char *device, int sectors)
-{
-	char *buffer;
-	int size = sectors * SECTOR_SIZE;
-	int r = -1;
-	int devfd;
+	for (i = 0, newline = 0; i < key_size; i += char_read) {
+		if (i == buflen) {
+			buflen += 4096;
+			pass = crypt_safe_realloc(pass, buflen);
+			if (!pass) {
+				log_err(cd, _("Out of memory while reading passphrase."));
+				r = -ENOMEM;
+				goto out_err;
+			}
+		}
 
-	devfd = open(device, O_RDWR | O_DIRECT | O_SYNC);
-	if(devfd == -1)
-		return -EINVAL;
+		if (flags & CRYPT_KEYFILE_STOP_EOL) {
+			/* If we should stop on newline, we must read the input
+			 * one character at the time. Otherwise we might end up
+			 * having read some bytes after the newline, which we
+			 * promised not to do.
+			 */
+			char_to_read = 1;
+		} else {
+			/* char_to_read = min(key_size - i, buflen - i) */
+			char_to_read = key_size < buflen ?
+				key_size - i : buflen - i;
+		}
+		char_read = read_buffer(fd, &pass[i], char_to_read);
+		if (char_read < 0) {
+			log_err(cd, _("Error reading passphrase."));
+			r = -EPIPE;
+			goto out_err;
+		}
 
-	buffer = malloc(size);
-	if (!buffer) {
-		close(devfd);
-		return -ENOMEM;
+		if (char_read == 0)
+			break;
+		/* Stop on newline only if not requested read from keyfile */
+		if ((flags & CRYPT_KEYFILE_STOP_EOL) && pass[i] == '\n') {
+			newline = 1;
+			pass[i] = '\0';
+			break;
+		}
 	}
-	memset(buffer, 0, size);
-
-	r = write_blockwise(devfd, buffer, size) < size ? -EIO : 0;
 
-	free(buffer);
-	close(devfd);
+	/* Fail if piped input dies reading nothing */
+	if (!i && !regular_file && !newline) {
+		log_err(cd, _("Nothing to read on input."));
+		r = -EPIPE;
+		goto out_err;
+	}
 
-	return r;
-}
+	/* Fail if we exceeded internal default (no specified size) */
+	if (unlimited_read && i == key_size) {
+		log_err(cd, _("Maximum keyfile size exceeded."));
+		goto out_err;
+	}
 
-/* MEMLOCK */
-#define DEFAULT_PROCESS_PRIORITY -18
+	if (!unlimited_read && i != key_size) {
+		log_err(cd, _("Cannot read requested amount of data."));
+		goto out_err;
+	}
 
-static int _priority;
-static int _memlock_count = 0;
+	*key = pass;
+	*key_size_read = i;
+	r = 0;
+out_err:
+	if (fd != STDIN_FILENO)
+		close(fd);
 
-// return 1 if memory is locked
-int crypt_memlock_inc(struct crypt_device *ctx)
-{
-	if (!_memlock_count++) {
-		log_dbg("Locking memory.");
-		if (mlockall(MCL_CURRENT | MCL_FUTURE)) {
-			log_err(ctx, _("WARNING!!! Possibly insecure memory. Are you root?\n"));
-			_memlock_count--;
-			return 0;
-		}
-		errno = 0;
-		if (((_priority = getpriority(PRIO_PROCESS, 0)) == -1) && errno)
-			log_err(ctx, _("Cannot get process priority.\n"));
-		else
-			if (setpriority(PRIO_PROCESS, 0, DEFAULT_PROCESS_PRIORITY))
-				log_err(ctx, _("setpriority %u failed: %s"),
-					DEFAULT_PROCESS_PRIORITY, strerror(errno));
-	}
-	return _memlock_count ? 1 : 0;
+	if (r)
+		crypt_safe_free(pass);
+	return r;
 }
 
-int crypt_memlock_dec(struct crypt_device *ctx)
+int crypt_keyfile_read(struct crypt_device *cd,  const char *keyfile,
+		       char **key, size_t *key_size_read,
+		       size_t keyfile_offset, size_t keyfile_size_max,
+		       uint32_t flags)
 {
-	if (_memlock_count && (!--_memlock_count)) {
-		log_dbg("Unlocking memory.");
-		if (munlockall())
-			log_err(ctx, _("Cannot unlock memory."));
-		if (setpriority(PRIO_PROCESS, 0, _priority))
-			log_err(ctx, _("setpriority %u failed: %s"), _priority, strerror(errno));
-	}
-	return _memlock_count ? 1 : 0;
+	return crypt_keyfile_device_read(cd, keyfile, key, key_size_read,
+					 keyfile_offset, keyfile_size_max, flags);
 }
 
-/* DEVICE TOPOLOGY */
+int kernel_version(uint64_t *kversion)
+{
+	struct utsname uts;
+	uint16_t maj, min, patch, rel;
+	int r = -EINVAL;
 
-/* block device topology ioctls, introduced in 2.6.32 */
-#ifndef BLKIOMIN
-#define BLKIOMIN    _IO(0x12,120)
-#define BLKIOOPT    _IO(0x12,121)
-#define BLKALIGNOFF _IO(0x12,122)
-#endif
+	if (uname(&uts) < 0)
+		return r;
 
-void get_topology_alignment(const char *device,
-			    unsigned long *required_alignment, /* bytes */
-			    unsigned long *alignment_offset,   /* bytes */
-			    unsigned long default_alignment)
-{
-	int dev_alignment_offset = 0;
-	unsigned int min_io_size = 0, opt_io_size = 0;
-	unsigned long temp_alignment = 0;
-	int fd;
-
-	*required_alignment = default_alignment;
-	*alignment_offset = 0;
-
-	fd = open(device, O_RDONLY);
-	if (fd == -1)
-		return;
-
-	/* minimum io size */
-	if (ioctl(fd, BLKIOMIN, &min_io_size) == -1) {
-		log_dbg("Topology info for %s not supported, using default offset %lu bytes.",
-			device, default_alignment);
-		goto out;
+	if (sscanf(uts.release, "%" SCNu16  ".%" SCNu16 ".%" SCNu16 "-%" SCNu16,
+		   &maj, &min, &patch, &rel) == 4)
+		r = 0;
+	else if (sscanf(uts.release,  "%" SCNu16 ".%" SCNu16 ".%" SCNu16,
+			&maj, &min, &patch) == 3) {
+		rel = 0;
+		r = 0;
 	}
 
-	/* optimal io size */
-	if (ioctl(fd, BLKIOOPT, &opt_io_size) == -1)
-		opt_io_size = min_io_size;
+	if (!r)
+		*kversion = version(maj, min, patch, rel);
 
-	/* alignment offset, bogus -1 means misaligned/unknown */
-	if (ioctl(fd, BLKALIGNOFF, &dev_alignment_offset) == -1 || dev_alignment_offset < 0)
-		dev_alignment_offset = 0;
-	*alignment_offset = (unsigned long)dev_alignment_offset;
+	return r;
+}
 
-	temp_alignment = (unsigned long)min_io_size;
+bool crypt_string_in(const char *str, char **list, size_t list_size)
+{
+	size_t i;
 
-	if (temp_alignment < (unsigned long)opt_io_size)
-		temp_alignment = (unsigned long)opt_io_size;
+	for (i = 0; *list && i < list_size; i++, list++)
+		if (!strcmp(str, *list))
+			return true;
 
-	/* If calculated alignment is multiple of default, keep default */
-	if (temp_alignment && (default_alignment % temp_alignment))
-		*required_alignment = temp_alignment;
+	return false;
+}
 
-	log_dbg("Topology: IO (%u/%u), offset = %lu; Required alignment is %lu bytes.",
-		min_io_size, opt_io_size, *alignment_offset, *required_alignment);
-out:
-	(void)close(fd);
+/* compare two strings (allows NULL values) */
+int crypt_strcmp(const char *a, const char *b)
+{
+	if (!a && !b)
+		return 0;
+	else if (!a || !b)
+		return 1;
+	return strcmp(a, b);
 }