1/*
2 * Copyright (c) 2019 Conrad Meyer <cem@FreeBSD.org>.  All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23 * SUCH DAMAGE.
24 */
25
26#include <sys/cdefs.h>
27#include <assert.h>
28#include <err.h>
29#include <errno.h>
30#include <stdbool.h>
31#include <stdint.h>
32#include <stdio.h>
33#include <stdlib.h>
34#include <string.h>
35
36#include "fstyp.h"
37
38/*
39 * This really detects the container format, which might be best supported by
40 * geom_part or a special GEOM class.
41 *
42 * https://developer.apple.com/support/downloads/Apple-File-System-Reference.pdf
43 */
44
45#define	NX_CKSUM_SZ		8
46
47typedef uint64_t nx_oid_t;
48
49typedef uint64_t nx_xid_t;
50
51struct nx_obj {
52	uint8_t		o_cksum[NX_CKSUM_SZ];	/* Fletcher 64 */
53	nx_oid_t	o_oid;
54	nx_xid_t	o_xid;
55	uint32_t	o_type;
56	uint32_t	o_subtype;
57};
58
59/* nx_obj::o_oid */
60#define	OID_NX_SUPERBLOCK	1
61
62/* nx_obj::o_type: */
63#define	OBJECT_TYPE_MASK		0x0000ffff
64#define	OBJECT_TYPE_NX_SUPERBLOCK	0x00000001
65#define	OBJECT_TYPE_FLAGS_MASK		0xffff0000
66#define	OBJ_STORAGETYPE_MASK		0xc0000000
67#define	OBJECT_TYPE_FLAGS_DEFINED_MASK	0xf8000000
68#define	OBJ_STORAGE_VIRTUAL		0x00000000
69#define	OBJ_STORAGE_EPHEMERAL		0x80000000
70#define	OBJ_STORAGE_PHYSICAL		0x40000000
71#define	OBJ_NOHEADER			0x20000000
72#define	OBJ_ENCRYPTED			0x10000000
73#define	OBJ_NONPERSISTENT		0x08000000
74
75struct nx_superblock {
76	struct nx_obj	nx_o;
77	char		nx_magic[4];
78	/* ... other stuff that doesn't matter */
79};
80
81int
82fstyp_apfs(FILE *fp, char *label, size_t size)
83{
84	struct nx_superblock *csb;
85	int retval;
86
87	retval = 1;
88	csb = read_buf(fp, 0, sizeof(*csb));
89	if (csb == NULL)
90		goto fail;
91
92	/* Ideally, checksum the SB here. */
93	if (strncmp(csb->nx_magic, "NXSB", 4) != 0 ||
94	    csb->nx_o.o_oid != OID_NX_SUPERBLOCK ||
95	    (csb->nx_o.o_type & OBJECT_TYPE_MASK) != OBJECT_TYPE_NX_SUPERBLOCK)
96		goto fail;
97
98	retval = 0;
99
100	/* No label support yet. */
101	(void)size;
102	(void)label;
103
104fail:
105	free(csb);
106	return (retval);
107}
108