xref: /freebsd/usr.sbin/fstyp/ntfs.c (revision f39bffc62c1395bde25d152c7f68fdf7cbaab414)
1 /*-
2  * Copyright (c) 2005 Takanori Watanabe
3  * Copyright (c) 2014 The FreeBSD Foundation
4  * All rights reserved.
5  *
6  * This software was developed by Edward Tomasz Napierala under sponsorship
7  * from the FreeBSD Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include <stdint.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <string.h>
38 
39 #include "fstyp.h"
40 
41 #define	NTFS_A_VOLUMENAME	0x60
42 #define	NTFS_FILEMAGIC		((uint32_t)(0x454C4946))
43 #define	NTFS_VOLUMEINO		3
44 
45 struct ntfs_attr {
46 	uint32_t	a_type;
47 	uint32_t	reclen;
48 	uint8_t		a_flag;
49 	uint8_t		a_namelen;
50 	uint8_t		a_nameoff;
51 	uint8_t		reserved1;
52 	uint8_t		a_compression;
53 	uint8_t		reserved2;
54 	uint16_t	a_index;
55 	uint16_t	a_datalen;
56 	uint16_t	reserved3;
57 	uint16_t	a_dataoff;
58 	uint16_t	a_indexed;
59 } __packed;
60 
61 struct ntfs_filerec {
62 	uint32_t	fr_hdrmagic;
63 	uint16_t	fr_hdrfoff;
64 	uint16_t	fr_hdrfnum;
65 	uint8_t		reserved[8];
66 	uint16_t	fr_seqnum;
67 	uint16_t	fr_nlink;
68 	uint16_t	fr_attroff;
69 	uint16_t	fr_flags;
70 	uint32_t	fr_size;
71 	uint32_t	fr_allocated;
72 	uint64_t	fr_mainrec;
73 	uint16_t	fr_attrnum;
74 } __packed;
75 
76 struct ntfs_bootfile {
77 	uint8_t		reserved1[3];
78 	uint8_t		bf_sysid[8];
79 	uint16_t	bf_bps;
80 	uint8_t		bf_spc;
81 	uint8_t		reserved2[7];
82 	uint8_t		bf_media;
83 	uint8_t		reserved3[2];
84 	uint16_t	bf_spt;
85 	uint16_t	bf_heads;
86 	uint8_t		reserver4[12];
87 	uint64_t	bf_spv;
88 	uint64_t	bf_mftcn;
89 	uint64_t	bf_mftmirrcn;
90 	int8_t		bf_mftrecsz;
91 	uint32_t	bf_ibsz;
92 	uint32_t	bf_volsn;
93 } __packed;
94 
95 int
96 fstyp_ntfs(FILE *fp, char *label, size_t size)
97 {
98 	struct ntfs_bootfile *bf;
99 	struct ntfs_filerec *fr;
100 	struct ntfs_attr *atr;
101 	off_t voloff;
102 	char *filerecp, *ap;
103 	int8_t mftrecsz;
104 	char vnchar;
105 	int recsize, j;
106 
107 	filerecp = NULL;
108 
109 	bf = (struct ntfs_bootfile *)read_buf(fp, 0, 512);
110 	if (bf == NULL || strncmp(bf->bf_sysid, "NTFS    ", 8) != 0)
111 		goto fail;
112 
113 	mftrecsz = bf->bf_mftrecsz;
114 	recsize = (mftrecsz > 0) ? (mftrecsz * bf->bf_bps * bf->bf_spc) : (1 << -mftrecsz);
115 
116 	voloff = bf->bf_mftcn * bf->bf_spc * bf->bf_bps +
117 	    recsize * NTFS_VOLUMEINO;
118 
119 	filerecp = read_buf(fp, voloff, recsize);
120 	if (filerecp == NULL)
121 		goto fail;
122 	fr = (struct ntfs_filerec *)filerecp;
123 
124 	if (fr->fr_hdrmagic != NTFS_FILEMAGIC)
125 		goto fail;
126 
127 	for (ap = filerecp + fr->fr_attroff;
128 	    atr = (struct ntfs_attr *)ap, (int)atr->a_type != -1;
129 	    ap += atr->reclen) {
130 		if (atr->a_type == NTFS_A_VOLUMENAME) {
131 			if(atr->a_datalen >= size *2){
132 				goto fail;
133 			}
134 			/*
135 			 *UNICODE to ASCII.
136 			 * Should we need to use iconv(9)?
137 			 */
138 			for (j = 0; j < atr->a_datalen; j++) {
139 				vnchar = *(ap + atr->a_dataoff + j);
140 				if (j & 1) {
141 					if (vnchar) {
142 						goto fail;
143 					}
144 				} else {
145 					label[j / 2] = vnchar;
146 				}
147 			}
148 			label[j / 2] = 0;
149 			break;
150 		}
151 	}
152 
153 	free(bf);
154 	free(filerecp);
155 
156 	return (0);
157 
158 fail:
159 	free(bf);
160 	free(filerecp);
161 
162 	return (1);
163 }
164