xref: /freebsd/usr.sbin/fstyp/ntfs.c (revision 2e3f49888ec8851bafb22011533217487764fdb0)
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 #include <err.h>
33 #ifdef WITH_ICONV
34 #include <iconv.h>
35 #endif
36 #include <stdint.h>
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <string.h>
40 
41 #include "fstyp.h"
42 
43 #define	NTFS_A_VOLUMENAME	0x60
44 #define	NTFS_FILEMAGIC		((uint32_t)(0x454C4946))
45 #define	NTFS_VOLUMEINO		3
46 
47 struct ntfs_attr {
48 	uint32_t	a_type;
49 	uint32_t	reclen;
50 	uint8_t		a_flag;
51 	uint8_t		a_namelen;
52 	uint8_t		a_nameoff;
53 	uint8_t		reserved1;
54 	uint8_t		a_compression;
55 	uint8_t		reserved2;
56 	uint16_t	a_index;
57 	uint16_t	a_datalen;
58 	uint16_t	reserved3;
59 	uint16_t	a_dataoff;
60 	uint16_t	a_indexed;
61 } __packed;
62 
63 struct ntfs_filerec {
64 	uint32_t	fr_hdrmagic;
65 	uint16_t	fr_hdrfoff;
66 	uint16_t	fr_hdrfnum;
67 	uint8_t		reserved[8];
68 	uint16_t	fr_seqnum;
69 	uint16_t	fr_nlink;
70 	uint16_t	fr_attroff;
71 	uint16_t	fr_flags;
72 	uint32_t	fr_size;
73 	uint32_t	fr_allocated;
74 	uint64_t	fr_mainrec;
75 	uint16_t	fr_attrnum;
76 } __packed;
77 
78 struct ntfs_bootfile {
79 	uint8_t		reserved1[3];
80 	uint8_t		bf_sysid[8];
81 	uint16_t	bf_bps;
82 	uint8_t		bf_spc;
83 	uint8_t		reserved2[7];
84 	uint8_t		bf_media;
85 	uint8_t		reserved3[2];
86 	uint16_t	bf_spt;
87 	uint16_t	bf_heads;
88 	uint8_t		reserver4[12];
89 	uint64_t	bf_spv;
90 	uint64_t	bf_mftcn;
91 	uint64_t	bf_mftmirrcn;
92 	int8_t		bf_mftrecsz;
93 	uint32_t	bf_ibsz;
94 	uint32_t	bf_volsn;
95 } __packed;
96 
97 #ifdef WITH_ICONV
98 static void
99 convert_label(const void *label /* LE */, size_t labellen, char *label_out,
100     size_t label_sz)
101 {
102 	char *label_out_orig;
103 	iconv_t cd;
104 	size_t rc;
105 
106 	/* dstname="" means convert to the current locale. */
107 	cd = iconv_open("", NTFS_ENC);
108 	if (cd == (iconv_t)-1) {
109 		warn("ntfs: Could not open iconv");
110 		return;
111 	}
112 
113 	label_out_orig = label_out;
114 
115 	rc = iconv(cd, __DECONST(char **, &label), &labellen, &label_out,
116 	    &label_sz);
117 	if (rc == (size_t)-1) {
118 		warn("ntfs: iconv()");
119 		*label_out_orig = '\0';
120 	} else {
121 		/* NUL-terminate result (iconv advances label_out). */
122 		if (label_sz == 0)
123 			label_out--;
124 		*label_out = '\0';
125 	}
126 
127 	iconv_close(cd);
128 }
129 #endif
130 
131 int
132 fstyp_ntfs(FILE *fp, char *label, size_t size)
133 {
134 	struct ntfs_bootfile *bf;
135 	char *filerecp;
136 #ifdef WITH_ICONV
137 	struct ntfs_filerec *fr;
138 	struct ntfs_attr *atr;
139 	off_t voloff;
140 	char *ap;
141 	int8_t mftrecsz;
142 	int recsize;
143 #endif /* WITH_ICONV */
144 
145 	filerecp = NULL;
146 
147 	bf = (struct ntfs_bootfile *)read_buf(fp, 0, 512);
148 	if (bf == NULL || strncmp(bf->bf_sysid, "NTFS    ", 8) != 0)
149 		goto fail;
150 #ifdef WITH_ICONV
151 	if (!show_label)
152 		goto ok;
153 
154 	mftrecsz = bf->bf_mftrecsz;
155 	recsize = (mftrecsz > 0) ? (mftrecsz * bf->bf_bps * bf->bf_spc) : (1 << -mftrecsz);
156 
157 	voloff = bf->bf_mftcn * bf->bf_spc * bf->bf_bps +
158 	    recsize * NTFS_VOLUMEINO;
159 
160 	filerecp = read_buf(fp, voloff, recsize);
161 	if (filerecp == NULL)
162 		goto fail;
163 	fr = (struct ntfs_filerec *)filerecp;
164 
165 	if (fr->fr_hdrmagic != NTFS_FILEMAGIC)
166 		goto fail;
167 
168 	for (ap = filerecp + fr->fr_attroff;
169 	    atr = (struct ntfs_attr *)ap, (int)atr->a_type != -1;
170 	    ap += atr->reclen) {
171 		if (atr->a_type != NTFS_A_VOLUMENAME)
172 			continue;
173 
174 		convert_label(ap + atr->a_dataoff,
175 		    atr->a_datalen, label, size);
176 		break;
177 	}
178 
179 ok:
180 #else
181 	if (show_label) {
182 		warnx("label not available without iconv support");
183 		memset(label, 0, size);
184 	}
185 #endif /* WITH_ICONV */
186 	free(bf);
187 	free(filerecp);
188 
189 	return (0);
190 
191 fail:
192 	free(bf);
193 	free(filerecp);
194 
195 	return (1);
196 }
197