libblkid: Check offset in LUKS2 header

[thirdparty/util-linux.git] / libblkid / src / superblocks / luks.c

diff --git a/libblkid/src/superblocks/luks.c b/libblkid/src/superblocks/luks.c
index 0230b349267081966641122a0dbbecc57df47e6d..4623c98fc9d64db75504a7b09b4566cec2f2dc30 100644 (file)
--- a/libblkid/src/superblocks/luks.c
+++ b/libblkid/src/superblocks/luks.c
@@ -1,6 +1,6 @@
 /*
  * Copyright (C) 2008 Karel Zak <kzak@redhat.com>
- * Copyright (C) 2018 Milan Broz <gmazyland@gmail.com>
+ * Copyright (C) 2018-2024 Milan Broz <gmazyland@gmail.com>
  *
  * Inspired by libvolume_id by
  *     Kay Sievers <kay.sievers@vrfy.org>
@@ -15,6 +15,7 @@
 #include <errno.h>
 #include <ctype.h>
 #include <stdint.h>
+#include <stdbool.h>
 
 #include "superblocks.h"
 
@@ -96,6 +97,19 @@ static int luks_attributes(blkid_probe pr, struct luks2_phdr *header, uint64_t o
        return BLKID_PROBE_OK;
 }
 
+static bool luks_valid(struct luks2_phdr *header, const char *magic, uint64_t offset)
+{
+       if (memcmp(header->magic, magic, LUKS_MAGIC_L))
+               return false;
+
+       /* LUKS2 header is not at expected offset */
+       if (be16_to_cpu(header->version) == 2 &&
+           be64_to_cpu(header->hdr_offset) != offset)
+               return false;
+
+       return true;
+}
+
 static int probe_luks(blkid_probe pr, const struct blkid_idmag *mag __attribute__((__unused__)))
 {
        struct luks2_phdr *header;
@@ -105,7 +119,7 @@ static int probe_luks(blkid_probe pr, const struct blkid_idmag *mag __attribute_
        if (!header)
                return errno ? -errno : BLKID_PROBE_NONE;
 
-       if (!memcmp(header->magic, LUKS_MAGIC, LUKS_MAGIC_L)) {
+       if (luks_valid(header, LUKS_MAGIC, 0)) {
                /* LUKS primary header was found. */
                return luks_attributes(pr, header, 0);
        }
@@ -118,7 +132,7 @@ static int probe_luks(blkid_probe pr, const struct blkid_idmag *mag __attribute_
                if (!header)
                        return errno ? -errno : BLKID_PROBE_NONE;
 
-               if (!memcmp(header->magic, LUKS_MAGIC_2, LUKS_MAGIC_L))
+               if (luks_valid(header, LUKS_MAGIC_2, secondary_offsets[i]))
                        return luks_attributes(pr, header, secondary_offsets[i]);
        }