volume_id: add checksum check to via_raid

[elogind.git] / extras / volume_id / lib / via_raid.c

diff --git a/extras/volume_id/lib/via_raid.c b/extras/volume_id/lib/via_raid.c
index 42cb0980651ad46ca6d1a2bc7eb63e9d01afc50a..62c165e03468eb15d611055355dfc47247f582f5 100644 (file)
--- a/extras/volume_id/lib/via_raid.c
+++ b/extras/volume_id/lib/via_raid.c
@@ -3,6 +3,9 @@
  *
  * Copyright (C) 2005 Kay Sievers <kay.sievers@vrfy.org>
  *
+ * Based on information taken from dmraid:
+ * Copyright (C) 2004-2006 Heinz Mauelshagen, Red Hat GmbH
+ *
  *     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 of the License.
@@ -30,7 +33,7 @@ struct via_meta {
        uint16_t        signature;
        uint8_t         version_number;
        struct via_array {
-               uint16_t        disk_bits;
+               uint16_t        disk_bit_mask;
                uint8_t         disk_array_ex;
                uint32_t        capacity_low;
                uint32_t        capacity_high;
@@ -42,6 +45,18 @@ struct via_meta {
 
 #define VIA_SIGNATURE          0xAA55
 
+/* 8 bit checksum on first 50 bytes of metadata. */
+static uint8_t meta_checksum(struct via_meta *via)
+{
+       uint8_t i = 50, sum = 0;
+
+       while (i--)
+               sum += ((uint8_t*) via)[i];
+
+       return sum == via->checksum;
+}
+
+
 int volume_id_probe_via_raid(struct volume_id *id, uint64_t off, uint64_t size)
 {
        const uint8_t *buf;
@@ -67,6 +82,9 @@ int volume_id_probe_via_raid(struct volume_id *id, uint64_t off, uint64_t size)
        if (via->version_number > 1)
                return -1;
 
+       if (!meta_checksum(via))
+               return -1;
+
        volume_id_set_usage(id, VOLUME_ID_RAID);
        snprintf(id->type_version, sizeof(id->type_version)-1, "%u", via->version_number);
        id->type = "via_raid_member";