From 378c18e5f024ac5a8aef4cb40d7c9aa9633d144c Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 16:30:35 +0200 Subject: Adding upstream version 2.38.1. Signed-off-by: Daniel Baumann --- libblkid/src/superblocks/apfs.c | 83 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 83 insertions(+) create mode 100644 libblkid/src/superblocks/apfs.c (limited to 'libblkid/src/superblocks/apfs.c') diff --git a/libblkid/src/superblocks/apfs.c b/libblkid/src/superblocks/apfs.c new file mode 100644 index 0000000..3332ef2 --- /dev/null +++ b/libblkid/src/superblocks/apfs.c @@ -0,0 +1,83 @@ +/* + * Copyright (C) 2018 Harry Mallon + * + * This file may be redistributed under the terms of the + * GNU Lesser General Public License. + */ + +#include "superblocks.h" + +#define APFS_CONTAINER_SUPERBLOCK_TYPE 1 +#define APFS_CONTAINER_SUPERBLOCK_SUBTYPE 0 +#define APFS_STANDARD_BLOCK_SIZE 4096 + +/* + * This struct is much longer than this, but this seems + * to contain the useful bits (for now). + * + * All values are little-endian. + */ +struct apfs_super_block { + // Generic part to all APFS objects + uint64_t checksum; + uint64_t oid; + uint64_t xid; + uint16_t type; + uint16_t flags; + uint16_t subtype; + uint16_t pad; + + // Specific to container header + uint32_t magic; // 'NXSB' + uint32_t block_size; + uint64_t block_count; + uint64_t features; + uint64_t read_only_features; + uint64_t incompatible_features; + uint8_t uuid[16]; +}; + +static int probe_apfs(blkid_probe pr, const struct blkid_idmag *mag) +{ + struct apfs_super_block *sb; + + sb = blkid_probe_get_sb(pr, mag, struct apfs_super_block); + if (!sb) + return errno ? -errno : BLKID_PROBE_NONE; + + if (le16_to_cpu(sb->type) != APFS_CONTAINER_SUPERBLOCK_TYPE) + return BLKID_PROBE_NONE; + + if (le16_to_cpu(sb->subtype) != APFS_CONTAINER_SUPERBLOCK_SUBTYPE) + return BLKID_PROBE_NONE; + + if (le16_to_cpu(sb->pad) != 0) + return BLKID_PROBE_NONE; + + /* + * This check is pretty draconian, but should avoid false + * positives. Can be improved as more APFS documentation + * is published. + */ + if (le32_to_cpu(sb->block_size) != APFS_STANDARD_BLOCK_SIZE) + return BLKID_PROBE_NONE; + + if (blkid_probe_set_uuid(pr, sb->uuid) < 0) + return BLKID_PROBE_NONE; + + blkid_probe_set_block_size(pr, le32_to_cpu(sb->block_size)); + + return BLKID_PROBE_OK; +} + +const struct blkid_idinfo apfs_idinfo = +{ + .name = "apfs", + .usage = BLKID_USAGE_FILESYSTEM, + .probefunc = probe_apfs, + .magics = + { + { .magic = "NXSB", .len = 4, .sboff = 32 }, + { NULL } + } +}; -- cgit v1.2.3