Fix reencryption tool to work with 4k devices.

See https://bugzilla.redhat.com/show_bug.cgi?id=1029032#c7

Thanks to Ondra Kozina to figure this out.

src/cryptsetup_reencrypt.c

@@ -122,6 +122,12 @@ static int alignment(int fd)
 	return alignment;
 }
 
+static size_t pagesize(void)
+{
+	long r = sysconf(_SC_PAGESIZE);
+	return r < 0 ? 4096 : (size_t)r;
+}
+
 /* Depends on the first two fields of LUKS1 header format, magic and version */
 static int device_check(struct reenc_ctx *rc, header_magic set_magic)
 {
@@ -129,6 +135,7 @@ static int device_check(struct reenc_ctx *rc, header_magic set_magic)
 	int r, devfd;
 	ssize_t s;
 	uint16_t version;
+	size_t buf_size = pagesize();
 
 	devfd = open(rc->device, O_RDWR | O_EXCL | O_DIRECT);
 	if (devfd == -1) {
@@ -146,14 +153,14 @@ static int device_check(struct reenc_ctx *rc, header_magic set_magic)
 		goto out;
 	}
 
-	if (posix_memalign((void *)&buf, alignment(devfd), SECTOR_SIZE)) {
+	if (posix_memalign((void *)&buf, alignment(devfd), buf_size)) {
 		log_err(_("Allocation of aligned memory failed.\n"));
 		r = -ENOMEM;
 		goto out;
 	}
 
-	s = read(devfd, buf, SECTOR_SIZE);
+	s = read(devfd, buf, buf_size);
-	if (s < 0 || s != SECTOR_SIZE) {
+	if (s < 0 || s != buf_size) {
 		log_err(_("Cannot read device %s.\n"), rc->device);
 		r = -EIO;
 		goto out;
@@ -184,8 +191,8 @@ static int device_check(struct reenc_ctx *rc, header_magic set_magic)
 	if (!r) {
 		if (lseek(devfd, 0, SEEK_SET) == -1)
 			goto out;
-		s = write(devfd, buf, SECTOR_SIZE);
+		s = write(devfd, buf, buf_size);
-		if (s < 0 || s != SECTOR_SIZE) {
+		if (s < 0 || s != buf_size) {
 			log_err(_("Cannot write device %s.\n"), rc->device);
 			r = -EIO;
 		}
@@ -193,7 +200,7 @@ static int device_check(struct reenc_ctx *rc, header_magic set_magic)
 		log_dbg("LUKS signature check failed for %s.", rc->device);
 out:
 	if (buf)
-		memset(buf, 0, SECTOR_SIZE);
+		memset(buf, 0, buf_size);
 	free(buf);
 	close(devfd);
 	return r;

tests/reencryption-compat-test

@@ -12,6 +12,13 @@ PWD1="93R4P4pIqAH8"
 PWD2="1cND4319812f"
 PWD3="1-9Qu5Ejfnqv"
 
+
+function del_scsi_device()
+{
+	rmmod scsi_debug 2>/dev/null
+	sleep 2
+}
+
 function remove_mapping()
 {
 	[ -b /dev/mapper/$DEV_NAME2 ] && dmsetup remove $DEV_NAME2
@@ -19,6 +26,7 @@ function remove_mapping()
 	[ ! -z "$LOOPDEV1" ] && losetup -d $LOOPDEV1 >/dev/null 2>&1
 	rm -f $IMG $ORIG_IMG $KEY1 >/dev/null 2>&1
 	LOOPDEV1=""
+	del_scsi_device
 }
 
 function fail()
@@ -35,6 +43,19 @@ function skip()
 	exit 0
 }
 
+function add_scsi_device() {
+	del_scsi_device
+        modprobe scsi_debug $@
+        if [ $? -ne 0 ] ; then
+                echo "This kernel seems to not support proper scsi_debug module, test skipped."
+                exit 0
+        fi
+
+        sleep 2
+        SCSI_DEV="/dev/"$(grep scsi_debug /sys/block/*/device/model | cut -f4 -d /)
+        [ -b $SCSI_DEV ] || fail "Cannot find $SCSI_DEV."
+}
+
 function open_crypt()
 {
 	if [ -n "$1" ] ; then
@@ -124,6 +145,21 @@ function check_slot() #space separeted list of ENABLED key slots
 	return 0
 }
 
+function simple_scsi_reenc()
+{
+	echo -n "$1"
+	echo $PWD1 | $CRYPTSETUP luksFormat -i1 $SCSI_DEV || fail
+
+	echo $PWD1 | $CRYPTSETUP luksOpen $SCSI_DEV $DEV_NAME || fail
+	HASH=$(sha256sum /dev/mapper/$DEV_NAME | cut -d' ' -f 1)
+	$CRYPTSETUP luksClose $DEV_NAME || fail
+
+	echo $PWD1 | $REENC -q -i 1 $SCSI_DEV || fail
+
+	echo $PWD1 | $CRYPTSETUP luksOpen $SCSI_DEV $DEV_NAME || fail
+	check_hash_dev /dev/mapper/$DEV_NAME $HASH
+	$CRYPTSETUP luksClose $DEV_NAME || fail
+}
 
 [ $(id -u) != 0 ] && skip "WARNING: You must be root to run this test, test skipped."
 [ ! -x "$REENC" ] && skip "Cannot find $REENC, test skipped."
@@ -210,5 +246,14 @@ echo "[6] Reencryption using all active keyslots"
 echo -e "$PWD2\n$PWD1\n$PWD2\n$PWD1\n$PWD2\n$PWD1\n$PWD2\n$PWD3" | $REENC -q $LOOPDEV1 || fail
 check_slot 0 1 2 3 4 5 6 7 || fail "All keyslots expected to be enabled"
 
+echo "[7] Reencryption of block devices with different block size"
+add_scsi_device sector_size=512 dev_size_mb=8
+simple_scsi_reenc "[512 sector]"
+add_scsi_device sector_size=4096 dev_size_mb=8
+simple_scsi_reenc "[4096 sector]"
+add_scsi_device sector_size=512 physblk_exp=3 dev_size_mb=8
+simple_scsi_reenc "[4096/512 sector]"
+echo "[OK]"
+
 remove_mapping
 exit 0