xref: /freebsd/usr.sbin/fstyp/ntfs.c (revision c6989859ae9388eeb46a24fe88f9b8d07101c710)
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 <err.h>
35 #ifdef WITH_ICONV
36 #include <iconv.h>
37 #endif
38 #include <stdint.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 
43 #include "fstyp.h"
44 
45 #define	NTFS_A_VOLUMENAME	0x60
46 #define	NTFS_FILEMAGIC		((uint32_t)(0x454C4946))
47 #define	NTFS_VOLUMEINO		3
48 
49 struct ntfs_attr {
50 	uint32_t	a_type;
51 	uint32_t	reclen;
52 	uint8_t		a_flag;
53 	uint8_t		a_namelen;
54 	uint8_t		a_nameoff;
55 	uint8_t		reserved1;
56 	uint8_t		a_compression;
57 	uint8_t		reserved2;
58 	uint16_t	a_index;
59 	uint16_t	a_datalen;
60 	uint16_t	reserved3;
61 	uint16_t	a_dataoff;
62 	uint16_t	a_indexed;
63 } __packed;
64 
65 struct ntfs_filerec {
66 	uint32_t	fr_hdrmagic;
67 	uint16_t	fr_hdrfoff;
68 	uint16_t	fr_hdrfnum;
69 	uint8_t		reserved[8];
70 	uint16_t	fr_seqnum;
71 	uint16_t	fr_nlink;
72 	uint16_t	fr_attroff;
73 	uint16_t	fr_flags;
74 	uint32_t	fr_size;
75 	uint32_t	fr_allocated;
76 	uint64_t	fr_mainrec;
77 	uint16_t	fr_attrnum;
78 } __packed;
79 
80 struct ntfs_bootfile {
81 	uint8_t		reserved1[3];
82 	uint8_t		bf_sysid[8];
83 	uint16_t	bf_bps;
84 	uint8_t		bf_spc;
85 	uint8_t		reserved2[7];
86 	uint8_t		bf_media;
87 	uint8_t		reserved3[2];
88 	uint16_t	bf_spt;
89 	uint16_t	bf_heads;
90 	uint8_t		reserver4[12];
91 	uint64_t	bf_spv;
92 	uint64_t	bf_mftcn;
93 	uint64_t	bf_mftmirrcn;
94 	int8_t		bf_mftrecsz;
95 	uint32_t	bf_ibsz;
96 	uint32_t	bf_volsn;
97 } __packed;
98 
99 #ifdef WITH_ICONV
100 static void
101 convert_label(const void *label /* LE */, size_t labellen, char *label_out,
102     size_t label_sz)
103 {
104 	char *label_out_orig;
105 	iconv_t cd;
106 	size_t rc;
107 
108 	/* dstname="" means convert to the current locale. */
109 	cd = iconv_open("", NTFS_ENC);
110 	if (cd == (iconv_t)-1) {
111 		warn("ntfs: Could not open iconv");
112 		return;
113 	}
114 
115 	label_out_orig = label_out;
116 
117 	rc = iconv(cd, __DECONST(char **, &label), &labellen, &label_out,
118 	    &label_sz);
119 	if (rc == (size_t)-1) {
120 		warn("ntfs: iconv()");
121 		*label_out_orig = '\0';
122 	} else {
123 		/* NUL-terminate result (iconv advances label_out). */
124 		if (label_sz == 0)
125 			label_out--;
126 		*label_out = '\0';
127 	}
128 
129 	iconv_close(cd);
130 }
131 #endif
132 
133 int
134 fstyp_ntfs(FILE *fp, char *label, size_t size)
135 {
136 	struct ntfs_bootfile *bf;
137 	char *filerecp;
138 #ifdef WITH_ICONV
139 	struct ntfs_filerec *fr;
140 	struct ntfs_attr *atr;
141 	off_t voloff;
142 	char *ap;
143 	int8_t mftrecsz;
144 	int recsize;
145 #endif /* WITH_ICONV */
146 
147 	filerecp = NULL;
148 
149 	bf = (struct ntfs_bootfile *)read_buf(fp, 0, 512);
150 	if (bf == NULL || strncmp(bf->bf_sysid, "NTFS    ", 8) != 0)
151 		goto fail;
152 #ifdef WITH_ICONV
153 	if (!show_label)
154 		goto ok;
155 
156 	mftrecsz = bf->bf_mftrecsz;
157 	recsize = (mftrecsz > 0) ? (mftrecsz * bf->bf_bps * bf->bf_spc) : (1 << -mftrecsz);
158 
159 	voloff = bf->bf_mftcn * bf->bf_spc * bf->bf_bps +
160 	    recsize * NTFS_VOLUMEINO;
161 
162 	filerecp = read_buf(fp, voloff, recsize);
163 	if (filerecp == NULL)
164 		goto fail;
165 	fr = (struct ntfs_filerec *)filerecp;
166 
167 	if (fr->fr_hdrmagic != NTFS_FILEMAGIC)
168 		goto fail;
169 
170 	for (ap = filerecp + fr->fr_attroff;
171 	    atr = (struct ntfs_attr *)ap, (int)atr->a_type != -1;
172 	    ap += atr->reclen) {
173 		if (atr->a_type != NTFS_A_VOLUMENAME)
174 			continue;
175 
176 		convert_label(ap + atr->a_dataoff,
177 		    atr->a_datalen, label, size);
178 		break;
179 	}
180 
181 ok:
182 #endif /* WITH_ICONV */
183 	free(bf);
184 	free(filerecp);
185 
186 	return (0);
187 
188 fail:
189 	free(bf);
190 	free(filerecp);
191 
192 	return (1);
193 }
194