xref: /freebsd/sys/fs/msdosfs/msdosfs_conv.c (revision b2d48be1bc7df45ddd13b143a160d0acb5a383c5)
1 /* $FreeBSD$ */
2 /*	$NetBSD: msdosfs_conv.c,v 1.25 1997/11/17 15:36:40 ws Exp $	*/
3 
4 /*-
5  * Copyright (C) 1995, 1997 Wolfgang Solfrank.
6  * Copyright (C) 1995, 1997 TooLs GmbH.
7  * All rights reserved.
8  * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below).
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by TooLs GmbH.
21  * 4. The name of TooLs GmbH may not be used to endorse or promote products
22  *    derived from this software without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
25  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
29  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
30  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
31  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
32  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
33  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 /*-
36  * Written by Paul Popelka (paulp@uts.amdahl.com)
37  *
38  * You can do anything you want with this software, just don't say you wrote
39  * it, and don't remove this notice.
40  *
41  * This software is provided "as is".
42  *
43  * The author supplies this software to be publicly redistributed on the
44  * understanding that the author is not responsible for the correct
45  * functioning of this software in any circumstances and is not liable for
46  * any damages caused by this software.
47  *
48  * October 1992
49  */
50 
51 #include <sys/param.h>
52 #include <sys/systm.h>
53 #include <sys/dirent.h>
54 #include <sys/iconv.h>
55 #include <sys/mount.h>
56 
57 #include <fs/msdosfs/bpb.h>
58 #include <fs/msdosfs/direntry.h>
59 #include <fs/msdosfs/msdosfsmount.h>
60 
61 extern struct iconv_functions *msdosfs_iconv;
62 
63 static int mbsadjpos(const char **, size_t, size_t, int, int, void *handle);
64 static u_char * dos2unixchr(u_char *, const u_char **, size_t *, int, struct msdosfsmount *);
65 static u_int16_t unix2doschr(const u_char **, size_t *, struct msdosfsmount *);
66 static u_char * win2unixchr(u_char *, u_int16_t, struct msdosfsmount *);
67 static u_int16_t unix2winchr(const u_char **, size_t *, int, struct msdosfsmount *);
68 
69 /*
70  * 0 - character disallowed in long file name.
71  * 1 - character should be replaced by '_' in DOS file name,
72  *     and generation number inserted.
73  * 2 - character ('.' and ' ') should be skipped in DOS file name,
74  *     and generation number inserted.
75  */
76 static u_char
77 unix2dos[256] = {
78 /* iso8859-1 -> cp850 */
79 	0,    0,    0,    0,    0,    0,    0,    0,	/* 00-07 */
80 	0,    0,    0,    0,    0,    0,    0,    0,	/* 08-0f */
81 	0,    0,    0,    0,    0,    0,    0,    0,	/* 10-17 */
82 	0,    0,    0,    0,    0,    0,    0,    0,	/* 18-1f */
83 	2,    0x21, 0,    0x23, 0x24, 0x25, 0x26, 0x27,	/* 20-27 */
84 	0x28, 0x29, 0,    1,    1,    0x2d, 2,    0,	/* 28-2f */
85 	0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,	/* 30-37 */
86 	0x38, 0x39, 0,    1,    0,    1,    0,    0,	/* 38-3f */
87 	0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,	/* 40-47 */
88 	0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,	/* 48-4f */
89 	0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,	/* 50-57 */
90 	0x58, 0x59, 0x5a, 1,    0,    1,    0x5e, 0x5f,	/* 58-5f */
91 	0x60, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,	/* 60-67 */
92 	0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,	/* 68-6f */
93 	0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,	/* 70-77 */
94 	0x58, 0x59, 0x5a, 0x7b, 0,    0x7d, 0x7e, 0,	/* 78-7f */
95 	0,    0,    0,    0,    0,    0,    0,    0,	/* 80-87 */
96 	0,    0,    0,    0,    0,    0,    0,    0,	/* 88-8f */
97 	0,    0,    0,    0,    0,    0,    0,    0,	/* 90-97 */
98 	0,    0,    0,    0,    0,    0,    0,    0,	/* 98-9f */
99 	0,    0xad, 0xbd, 0x9c, 0xcf, 0xbe, 0xdd, 0xf5,	/* a0-a7 */
100 	0xf9, 0xb8, 0xa6, 0xae, 0xaa, 0xf0, 0xa9, 0xee,	/* a8-af */
101 	0xf8, 0xf1, 0xfd, 0xfc, 0xef, 0xe6, 0xf4, 0xfa,	/* b0-b7 */
102 	0xf7, 0xfb, 0xa7, 0xaf, 0xac, 0xab, 0xf3, 0xa8,	/* b8-bf */
103 	0xb7, 0xb5, 0xb6, 0xc7, 0x8e, 0x8f, 0x92, 0x80,	/* c0-c7 */
104 	0xd4, 0x90, 0xd2, 0xd3, 0xde, 0xd6, 0xd7, 0xd8,	/* c8-cf */
105 	0xd1, 0xa5, 0xe3, 0xe0, 0xe2, 0xe5, 0x99, 0x9e,	/* d0-d7 */
106 	0x9d, 0xeb, 0xe9, 0xea, 0x9a, 0xed, 0xe8, 0xe1,	/* d8-df */
107 	0xb7, 0xb5, 0xb6, 0xc7, 0x8e, 0x8f, 0x92, 0x80,	/* e0-e7 */
108 	0xd4, 0x90, 0xd2, 0xd3, 0xde, 0xd6, 0xd7, 0xd8,	/* e8-ef */
109 	0xd1, 0xa5, 0xe3, 0xe0, 0xe2, 0xe5, 0x99, 0xf6,	/* f0-f7 */
110 	0x9d, 0xeb, 0xe9, 0xea, 0x9a, 0xed, 0xe8, 0x98,	/* f8-ff */
111 };
112 
113 static u_char
114 dos2unix[256] = {
115 /* cp850 -> iso8859-1 */
116 	0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f,	/* 00-07 */
117 	0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f,	/* 08-0f */
118 	0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f,	/* 10-17 */
119 	0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f,	/* 18-1f */
120 	0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,	/* 20-27 */
121 	0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,	/* 28-2f */
122 	0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,	/* 30-37 */
123 	0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,	/* 38-3f */
124 	0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,	/* 40-47 */
125 	0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,	/* 48-4f */
126 	0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,	/* 50-57 */
127 	0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,	/* 58-5f */
128 	0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,	/* 60-67 */
129 	0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,	/* 68-6f */
130 	0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,	/* 70-77 */
131 	0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f,	/* 78-7f */
132 	0xc7, 0xfc, 0xe9, 0xe2, 0xe4, 0xe0, 0xe5, 0xe7,	/* 80-87 */
133 	0xea, 0xeb, 0xe8, 0xef, 0xee, 0xec, 0xc4, 0xc5,	/* 88-8f */
134 	0xc9, 0xe6, 0xc6, 0xf4, 0xf6, 0xf2, 0xfb, 0xf9,	/* 90-97 */
135 	0xff, 0xd6, 0xdc, 0xf8, 0xa3, 0xd8, 0xd7, 0x3f,	/* 98-9f */
136 	0xe1, 0xed, 0xf3, 0xfa, 0xf1, 0xd1, 0xaa, 0xba,	/* a0-a7 */
137 	0xbf, 0xae, 0xac, 0xbd, 0xbc, 0xa1, 0xab, 0xbb,	/* a8-af */
138 	0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0xc1, 0xc2, 0xc0,	/* b0-b7 */
139 	0xa9, 0x3f, 0x3f, 0x3f, 0x3f, 0xa2, 0xa5, 0x3f,	/* b8-bf */
140 	0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0xe3, 0xc3,	/* c0-c7 */
141 	0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0x3f, 0xa4,	/* c8-cf */
142 	0xf0, 0xd0, 0xca, 0xcb, 0xc8, 0x3f, 0xcd, 0xce,	/* d0-d7 */
143 	0xcf, 0x3f, 0x3f, 0x3f, 0x3f, 0xa6, 0xcc, 0x3f,	/* d8-df */
144 	0xd3, 0xdf, 0xd4, 0xd2, 0xf5, 0xd5, 0xb5, 0xfe,	/* e0-e7 */
145 	0xde, 0xda, 0xdb, 0xd9, 0xfd, 0xdd, 0xaf, 0x3f,	/* e8-ef */
146 	0xad, 0xb1, 0x3f, 0xbe, 0xb6, 0xa7, 0xf7, 0xb8,	/* f0-f7 */
147 	0xb0, 0xa8, 0xb7, 0xb9, 0xb3, 0xb2, 0x3f, 0x3f,	/* f8-ff */
148 };
149 
150 static u_char
151 u2l[256] = {
152 /* tolower */
153 	0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, /* 00-07 */
154 	0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, /* 08-0f */
155 	0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, /* 10-17 */
156 	0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, /* 18-1f */
157 	0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, /* 20-27 */
158 	0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, /* 28-2f */
159 	0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, /* 30-37 */
160 	0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, /* 38-3f */
161 	0x40, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, /* 40-47 */
162 	0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, /* 48-4f */
163 	0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, /* 50-57 */
164 	0x78, 0x79, 0x7a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, /* 58-5f */
165 	0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, /* 60-67 */
166 	0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, /* 68-6f */
167 	0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, /* 70-77 */
168 	0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, /* 78-7f */
169 	0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, /* 80-87 */
170 	0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, /* 88-8f */
171 	0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, /* 90-97 */
172 	0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, /* 98-9f */
173 	0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, /* a0-a7 */
174 	0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, /* a8-af */
175 	0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, /* b0-b7 */
176 	0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, /* b8-bf */
177 	0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, /* c0-c7 */
178 	0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, /* c8-cf */
179 	0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xd7, /* d0-d7 */
180 	0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xdf, /* d8-df */
181 	0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, /* e0-e7 */
182 	0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, /* e8-ef */
183 	0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, /* f0-f7 */
184 	0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, /* f8-ff */
185 };
186 
187 static u_char
188 l2u[256] = {
189 /* toupper */
190 	0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, /* 00-07 */
191 	0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, /* 08-0f */
192 	0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, /* 10-17 */
193 	0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, /* 18-1f */
194 	0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, /* 20-27 */
195 	0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, /* 28-2f */
196 	0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, /* 30-37 */
197 	0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, /* 38-3f */
198 	0x40, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, /* 40-47 */
199 	0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, /* 48-4f */
200 	0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, /* 50-57 */
201 	0x78, 0x79, 0x7a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, /* 58-5f */
202 	0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, /* 60-67 */
203 	0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, /* 68-6f */
204 	0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, /* 70-77 */
205 	0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, /* 78-7f */
206 	0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, /* 80-87 */
207 	0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, /* 88-8f */
208 	0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, /* 90-97 */
209 	0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, /* 98-9f */
210 	0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, /* a0-a7 */
211 	0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, /* a8-af */
212 	0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, /* b0-b7 */
213 	0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, /* b8-bf */
214 	0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, /* c0-c7 */
215 	0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, /* c8-cf */
216 	0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xd7, /* d0-d7 */
217 	0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xdf, /* d8-df */
218 	0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, /* e0-e7 */
219 	0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, /* e8-ef */
220 	0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, /* f0-f7 */
221 	0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, /* f8-ff */
222 };
223 
224 /*
225  * DOS filenames are made of 2 parts, the name part and the extension part.
226  * The name part is 8 characters long and the extension part is 3
227  * characters long.  They may contain trailing blanks if the name or
228  * extension are not long enough to fill their respective fields.
229  */
230 
231 /*
232  * Convert a DOS filename to a unix filename. And, return the number of
233  * characters in the resulting unix filename excluding the terminating
234  * null.
235  */
236 int
237 dos2unixfn(u_char dn[11], u_char *un, int lower, struct msdosfsmount *pmp)
238 {
239 	size_t i;
240 	int thislong = 0;
241 	u_char *c, tmpbuf[5];
242 
243 	/*
244 	 * If first char of the filename is SLOT_E5 (0x05), then the real
245 	 * first char of the filename should be 0xe5. But, they couldn't
246 	 * just have a 0xe5 mean 0xe5 because that is used to mean a freed
247 	 * directory slot. Another dos quirk.
248 	 */
249 	if (*dn == SLOT_E5)
250 		*dn = 0xe5;
251 
252 	/*
253 	 * Copy the name portion into the unix filename string.
254 	 */
255 	for (i = 8; i > 0 && *dn != ' ';) {
256 		c = dos2unixchr(tmpbuf, __DECONST(const u_char **, &dn), &i,
257 		    lower & LCASE_BASE, pmp);
258 		while (*c != '\0') {
259 			*un++ = *c++;
260 			thislong++;
261 		}
262 	}
263 	dn += i;
264 
265 	/*
266 	 * Now, if there is an extension then put in a period and copy in
267 	 * the extension.
268 	 */
269 	if (*dn != ' ') {
270 		*un++ = '.';
271 		thislong++;
272 		for (i = 3; i > 0 && *dn != ' ';) {
273 			c = dos2unixchr(tmpbuf, __DECONST(const u_char **, &dn),
274 			    &i, lower & LCASE_EXT, pmp);
275 			while (*c != '\0') {
276 				*un++ = *c++;
277 				thislong++;
278 			}
279 		}
280 	}
281 	*un++ = 0;
282 
283 	return (thislong);
284 }
285 
286 /*
287  * Convert a unix filename to a DOS filename according to Win95 rules.
288  * If applicable and gen is not 0, it is inserted into the converted
289  * filename as a generation number.
290  * Returns
291  *	0 if name couldn't be converted
292  *	1 if the converted name is the same as the original
293  *	  (no long filename entry necessary for Win95)
294  *	2 if conversion was successful
295  *	3 if conversion was successful and generation number was inserted
296  */
297 int
298 unix2dosfn(const u_char *un, u_char dn[12], size_t unlen, u_int gen,
299     struct msdosfsmount *pmp)
300 {
301 	ssize_t i, j;
302 	int l;
303 	int conv = 1;
304 	const u_char *cp, *dp, *dp1;
305 	u_char gentext[6], *wcp;
306 	u_int16_t c;
307 
308 	/*
309 	 * Fill the dos filename string with blanks. These are DOS's pad
310 	 * characters.
311 	 */
312 	for (i = 0; i < 11; i++)
313 		dn[i] = ' ';
314 	dn[11] = 0;
315 
316 	/*
317 	 * The filenames "." and ".." are handled specially, since they
318 	 * don't follow dos filename rules.
319 	 */
320 	if (un[0] == '.' && unlen == 1) {
321 		dn[0] = '.';
322 		return gen <= 1;
323 	}
324 	if (un[0] == '.' && un[1] == '.' && unlen == 2) {
325 		dn[0] = '.';
326 		dn[1] = '.';
327 		return gen <= 1;
328 	}
329 
330 	/*
331 	 * Filenames with only blanks and dots are not allowed!
332 	 */
333 	for (cp = un, i = unlen; --i >= 0; cp++)
334 		if (*cp != ' ' && *cp != '.')
335 			break;
336 	if (i < 0)
337 		return 0;
338 
339 
340 	/*
341 	 * Filenames with some characters are not allowed!
342 	 */
343 	for (cp = un, i = unlen; i > 0;)
344 		if (unix2doschr(&cp, (size_t *)&i, pmp) == 0)
345 			return 0;
346 
347 	/*
348 	 * Now find the extension
349 	 * Note: dot as first char doesn't start extension
350 	 *	 and trailing dots and blanks are ignored
351 	 * Note(2003/7): It seems recent Windows has
352 	 *	 defferent rule than this code, that Windows
353 	 *	 ignores all dots before extension, and use all
354 	 * 	 chars as filename except for dots.
355 	 */
356 	dp = dp1 = 0;
357 	for (cp = un + 1, i = unlen - 1; --i >= 0;) {
358 		switch (*cp++) {
359 		case '.':
360 			if (!dp1)
361 				dp1 = cp;
362 			break;
363 		case ' ':
364 			break;
365 		default:
366 			if (dp1)
367 				dp = dp1;
368 			dp1 = 0;
369 			break;
370 		}
371 	}
372 
373 	/*
374 	 * Now convert it (this part is for extension).
375 	 * As Windows XP do, if it's not ascii char,
376 	 * this function should return 2 or 3, so that checkng out Unicode name.
377 	 */
378 	if (dp) {
379 		if (dp1)
380 			l = dp1 - dp;
381 		else
382 			l = unlen - (dp - un);
383 		for (cp = dp, i = l, j = 8; i > 0 && j < 11; j++) {
384 			c = unix2doschr(&cp, (size_t *)&i, pmp);
385 			if (c & 0xff00) {
386 				dn[j] = c >> 8;
387 				if (++j < 11) {
388 					dn[j] = c;
389 					if (conv != 3)
390 						conv = 2;
391 					continue;
392 				} else {
393 					conv = 3;
394 					dn[j-1] = ' ';
395 					break;
396 				}
397 			} else {
398 				dn[j] = c;
399 			}
400 			if (((dn[j] & 0x80) || *(cp - 1) != dn[j]) && conv != 3)
401 				conv = 2;
402 			if (dn[j] == 1) {
403 				conv = 3;
404 				dn[j] = '_';
405 			}
406 			if (dn[j] == 2) {
407 				conv = 3;
408 				dn[j--] = ' ';
409 			}
410 		}
411 		if (i > 0)
412 			conv = 3;
413 		dp--;
414 	} else {
415 		for (dp = cp; *--dp == ' ' || *dp == '.';);
416 		dp++;
417 	}
418 
419 	/*
420 	 * Now convert the rest of the name
421 	 */
422 	for (i = dp - un, j = 0; un < dp && j < 8; j++) {
423 		c = unix2doschr(&un, &i, pmp);
424 		if (c & 0xff00) {
425 			dn[j] = c >> 8;
426 			if (++j < 8) {
427 				dn[j] = c;
428 				if (conv != 3)
429 					conv = 2;
430 				continue;
431 			} else {
432 				conv = 3;
433 				dn[j-1] = ' ';
434 				break;
435 			}
436 		} else {
437 			dn[j] = c;
438 		}
439 		if (((dn[j] & 0x80) || *(un - 1) != dn[j]) && conv != 3)
440 			conv = 2;
441 		if (dn[j] == 1) {
442 			conv = 3;
443 			dn[j] = '_';
444 		}
445 		if (dn[j] == 2) {
446 			conv = 3;
447 			dn[j--] = ' ';
448 		}
449 	}
450 	if (un < dp)
451 		conv = 3;
452 	/*
453 	 * If we didn't have any chars in filename,
454 	 * generate a default
455 	 */
456 	if (!j)
457 		dn[0] = '_';
458 
459 	/*
460 	 * If there wasn't any char dropped,
461 	 * there is no place for generation numbers
462 	 */
463 	if (conv != 3) {
464 		if (gen > 1)
465 			conv = 0;
466 		goto done;
467 	}
468 
469 	/*
470 	 * Now insert the generation number into the filename part
471 	 */
472 	if (gen == 0)
473 		goto done;
474 	for (wcp = gentext + sizeof(gentext); wcp > gentext && gen; gen /= 10)
475 		*--wcp = gen % 10 + '0';
476 	if (gen) {
477 		conv = 0;
478 		goto done;
479 	}
480 	for (i = 8; dn[--i] == ' ';);
481 	i++;
482 	if (gentext + sizeof(gentext) - wcp + 1 > 8 - i)
483 		i = 8 - (gentext + sizeof(gentext) - wcp + 1);
484 	/*
485 	 * Correct posision to where insert the generation number
486 	 */
487 	cp = dn;
488 	i -= mbsadjpos((const char**)&cp, i, unlen, 1, pmp->pm_flags, pmp->pm_d2u);
489 
490 	dn[i++] = '~';
491 	while (wcp < gentext + sizeof(gentext))
492 		dn[i++] = *wcp++;
493 
494 	/*
495 	 * Tail of the filename should be space
496 	 */
497 	while (i < 8)
498 		dn[i++] = ' ';
499 	conv = 3;
500 
501 done:
502 	/*
503 	 * The first character cannot be E5,
504 	 * because that means a deleted entry
505 	 */
506 	if (dn[0] == 0xe5)
507 		dn[0] = SLOT_E5;
508 
509 	return conv;
510 }
511 
512 /*
513  * Create a Win95 long name directory entry
514  * Note: assumes that the filename is valid,
515  *	 i.e. doesn't consist solely of blanks and dots
516  */
517 int
518 unix2winfn(const u_char *un, size_t unlen, struct winentry *wep, int cnt,
519     int chksum, struct msdosfsmount *pmp)
520 {
521 	u_int8_t *wcp;
522 	int i, end;
523 	u_int16_t code;
524 
525 	/*
526 	 * Drop trailing blanks and dots
527 	 */
528 	unlen = winLenFixup(un, unlen);
529 
530 	/*
531 	 * Cut *un for this slot
532 	 */
533 	unlen = mbsadjpos((const char **)&un, unlen, (cnt - 1) * WIN_CHARS, 2,
534 			  pmp->pm_flags, pmp->pm_u2w);
535 
536 	/*
537 	 * Initialize winentry to some useful default
538 	 */
539 	for (wcp = (u_int8_t *)wep, i = sizeof(*wep); --i >= 0; *wcp++ = 0xff);
540 	wep->weCnt = cnt;
541 	wep->weAttributes = ATTR_WIN95;
542 	wep->weReserved1 = 0;
543 	wep->weChksum = chksum;
544 	wep->weReserved2 = 0;
545 
546 	/*
547 	 * Now convert the filename parts
548 	 */
549 	end = 0;
550 	for (wcp = wep->wePart1, i = sizeof(wep->wePart1)/2; --i >= 0 && !end;) {
551 		code = unix2winchr(&un, &unlen, 0, pmp);
552 		*wcp++ = code;
553 		*wcp++ = code >> 8;
554 		if (!code)
555 			end = WIN_LAST;
556 	}
557 	for (wcp = wep->wePart2, i = sizeof(wep->wePart2)/2; --i >= 0 && !end;) {
558 		code = unix2winchr(&un, &unlen, 0, pmp);
559 		*wcp++ = code;
560 		*wcp++ = code >> 8;
561 		if (!code)
562 			end = WIN_LAST;
563 	}
564 	for (wcp = wep->wePart3, i = sizeof(wep->wePart3)/2; --i >= 0 && !end;) {
565 		code = unix2winchr(&un, &unlen, 0, pmp);
566 		*wcp++ = code;
567 		*wcp++ = code >> 8;
568 		if (!code)
569 			end = WIN_LAST;
570 	}
571 	if (*un == '\0')
572 		end = WIN_LAST;
573 	wep->weCnt |= end;
574 	return !end;
575 }
576 
577 /*
578  * Compare our filename to the one in the Win95 entry
579  * Returns the checksum or -1 if no match
580  */
581 int
582 winChkName(struct mbnambuf *nbp, const u_char *un, size_t unlen, int chksum,
583     struct msdosfsmount *pmp)
584 {
585 	size_t len;
586 	u_int16_t c1, c2;
587 	u_char *np;
588 	struct dirent dirbuf;
589 
590 	/*
591 	 * We already have winentry in *nbp.
592 	 */
593 	if (!mbnambuf_flush(nbp, &dirbuf) || dirbuf.d_namlen == 0)
594 		return -1;
595 
596 #ifdef MSDOSFS_DEBUG
597 	printf("winChkName(): un=%s:%d,d_name=%s:%d\n", un, unlen,
598 							dirbuf.d_name,
599 							dirbuf.d_namlen);
600 #endif
601 
602 	/*
603 	 * Compare the name parts
604 	 */
605 	len = dirbuf.d_namlen;
606 	if (unlen != len)
607 		return -2;
608 
609 	for (np = dirbuf.d_name; unlen > 0 && len > 0;) {
610 		/*
611 		 * Comparison must be case insensitive, because FAT disallows
612 		 * to look up or create files in case sensitive even when
613 		 * it's a long file name.
614 		 */
615 		c1 = unix2winchr(__DECONST(const u_char **, &np), &len,
616 		    LCASE_BASE, pmp);
617 		c2 = unix2winchr(&un, &unlen, LCASE_BASE, pmp);
618 		if (c1 != c2)
619 			return -2;
620 	}
621 	return chksum;
622 }
623 
624 /*
625  * Convert Win95 filename to dirbuf.
626  * Returns the checksum or -1 if impossible
627  */
628 int
629 win2unixfn(struct mbnambuf *nbp, struct winentry *wep, int chksum,
630     struct msdosfsmount *pmp)
631 {
632 	u_char *c, tmpbuf[5];
633 	u_int8_t *cp;
634 	u_int8_t *np, name[WIN_CHARS * 3 + 1];
635 	u_int16_t code;
636 	int i;
637 
638 	if ((wep->weCnt&WIN_CNT) > howmany(WIN_MAXLEN, WIN_CHARS)
639 	    || !(wep->weCnt&WIN_CNT))
640 		return -1;
641 
642 	/*
643 	 * First compare checksums
644 	 */
645 	if (wep->weCnt&WIN_LAST) {
646 		chksum = wep->weChksum;
647 	} else if (chksum != wep->weChksum)
648 		chksum = -1;
649 	if (chksum == -1)
650 		return -1;
651 
652 	/*
653 	 * Convert the name parts
654 	 */
655 	np = name;
656 	for (cp = wep->wePart1, i = sizeof(wep->wePart1)/2; --i >= 0;) {
657 		code = (cp[1] << 8) | cp[0];
658 		switch (code) {
659 		case 0:
660 			*np = '\0';
661 			mbnambuf_write(nbp, name, (wep->weCnt & WIN_CNT) - 1);
662 			return chksum;
663 		case '/':
664 			*np = '\0';
665 			return -1;
666 		default:
667 			c = win2unixchr(tmpbuf, code, pmp);
668 			while (*c != '\0')
669 				*np++ = *c++;
670 			break;
671 		}
672 		cp += 2;
673 	}
674 	for (cp = wep->wePart2, i = sizeof(wep->wePart2)/2; --i >= 0;) {
675 		code = (cp[1] << 8) | cp[0];
676 		switch (code) {
677 		case 0:
678 			*np = '\0';
679 			mbnambuf_write(nbp, name, (wep->weCnt & WIN_CNT) - 1);
680 			return chksum;
681 		case '/':
682 			*np = '\0';
683 			return -1;
684 		default:
685 			c = win2unixchr(tmpbuf, code, pmp);
686 			while (*c != '\0')
687 				*np++ = *c++;
688 			break;
689 		}
690 		cp += 2;
691 	}
692 	for (cp = wep->wePart3, i = sizeof(wep->wePart3)/2; --i >= 0;) {
693 		code = (cp[1] << 8) | cp[0];
694 		switch (code) {
695 		case 0:
696 			*np = '\0';
697 			mbnambuf_write(nbp, name, (wep->weCnt & WIN_CNT) - 1);
698 			return chksum;
699 		case '/':
700 			*np = '\0';
701 			return -1;
702 		default:
703 			c = win2unixchr(tmpbuf, code, pmp);
704 			while (*c != '\0')
705 				*np++ = *c++;
706 			break;
707 		}
708 		cp += 2;
709 	}
710 	*np = '\0';
711 	mbnambuf_write(nbp, name, (wep->weCnt & WIN_CNT) - 1);
712 	return chksum;
713 }
714 
715 /*
716  * Compute the unrolled checksum of a DOS filename for Win95 LFN use.
717  */
718 u_int8_t
719 winChksum(u_int8_t *name)
720 {
721 	int i;
722 	u_int8_t s;
723 
724 	for (s = 0, i = 11; --i >= 0; s += *name++)
725 		s = (s << 7)|(s >> 1);
726 	return (s);
727 }
728 
729 /*
730  * Determine the number of slots necessary for Win95 names
731  */
732 int
733 winSlotCnt(const u_char *un, size_t unlen, struct msdosfsmount *pmp)
734 {
735 	size_t wlen;
736 	char wn[WIN_MAXLEN * 2 + 1], *wnp;
737 
738 	unlen = winLenFixup(un, unlen);
739 
740 	if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) {
741 		wlen = WIN_MAXLEN * 2;
742 		wnp = wn;
743 		msdosfs_iconv->conv(pmp->pm_u2w, (const char **)&un, &unlen, &wnp, &wlen);
744 		if (unlen > 0)
745 			return 0;
746 		return howmany(WIN_MAXLEN - wlen/2, WIN_CHARS);
747 	}
748 
749 	if (unlen > WIN_MAXLEN)
750 		return 0;
751 	return howmany(unlen, WIN_CHARS);
752 }
753 
754 /*
755  * Determine the number of bytes neccessary for Win95 names
756  */
757 size_t
758 winLenFixup(const u_char *un, size_t unlen)
759 {
760 	for (un += unlen; unlen > 0; unlen--)
761 		if (*--un != ' ' && *un != '.')
762 			break;
763 	return unlen;
764 }
765 
766 /*
767  * Store an area with multi byte string instr, and returns left
768  * byte of instr and moves pointer forward. The area's size is
769  * inlen or outlen.
770  */
771 static int
772 mbsadjpos(const char **instr, size_t inlen, size_t outlen, int weight, int flag, void *handle)
773 {
774 	char *outp, outstr[outlen * weight + 1];
775 
776 	if (flag & MSDOSFSMNT_KICONV && msdosfs_iconv) {
777 		outp = outstr;
778 		outlen *= weight;
779 		msdosfs_iconv->conv(handle, instr, &inlen, &outp, &outlen);
780 		return (inlen);
781 	}
782 
783 	(*instr) += min(inlen, outlen);
784 	return (inlen - min(inlen, outlen));
785 }
786 
787 /*
788  * Convert DOS char to Local char
789  */
790 static u_char *
791 dos2unixchr(u_char *outbuf, const u_char **instr, size_t *ilen, int lower, struct msdosfsmount *pmp)
792 {
793 	u_char c, *outp;
794 	size_t len, olen;
795 
796 	outp = outbuf;
797 	if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) {
798 		olen = len = 4;
799 
800 		if (lower & (LCASE_BASE | LCASE_EXT))
801 			msdosfs_iconv->convchr_case(pmp->pm_d2u, (const char **)instr,
802 						  ilen, (char **)&outp, &olen, KICONV_LOWER);
803 		else
804 			msdosfs_iconv->convchr(pmp->pm_d2u, (const char **)instr,
805 					     ilen, (char **)&outp, &olen);
806 		len -= olen;
807 
808 		/*
809 		 * return '?' if failed to convert
810 		 */
811 		if (len == 0) {
812 			(*ilen)--;
813 			(*instr)++;
814 			*outp++ = '?';
815 		}
816 	} else {
817 		(*ilen)--;
818 		c = *(*instr)++;
819 		c = dos2unix[c];
820 		if (lower & (LCASE_BASE | LCASE_EXT))
821 			c = u2l[c];
822 		*outp++ = c;
823 		outbuf[1] = '\0';
824 	}
825 
826 	*outp = '\0';
827 	outp = outbuf;
828 	return (outp);
829 }
830 
831 /*
832  * Convert Local char to DOS char
833  */
834 static u_int16_t
835 unix2doschr(const u_char **instr, size_t *ilen, struct msdosfsmount *pmp)
836 {
837 	u_char c;
838 	char *up, *outp, unicode[3], outbuf[3];
839 	u_int16_t wc;
840 	size_t len, ucslen, unixlen, olen;
841 
842 	if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) {
843 		/*
844 		 * to hide an invisible character, using a unicode filter
845 		 */
846 		ucslen = 2;
847 		len = *ilen;
848 		up = unicode;
849 		msdosfs_iconv->convchr(pmp->pm_u2w, (const char **)instr,
850 				     ilen, &up, &ucslen);
851 		unixlen = len - *ilen;
852 
853 		/*
854 		 * cannot be converted
855 		 */
856 		if (unixlen == 0) {
857 			(*ilen)--;
858 			(*instr)++;
859 			return (0);
860 		}
861 
862 		/*
863 		 * return magic number for ascii char
864 		 */
865 		if (unixlen == 1) {
866 			c = *(*instr -1);
867 			if (! (c & 0x80)) {
868 				c = unix2dos[c];
869 				if (c <= 2)
870 					return (c);
871 			}
872 		}
873 
874 		/*
875 		 * now convert using libiconv
876 		 */
877 		*instr -= unixlen;
878 		*ilen = len;
879 
880 		olen = len = 2;
881 		outp = outbuf;
882 		msdosfs_iconv->convchr_case(pmp->pm_u2d, (const char **)instr,
883 					  ilen, &outp, &olen, KICONV_FROM_UPPER);
884 		len -= olen;
885 
886 		/*
887 		 * cannot be converted, but has unicode char, should return magic number
888 		 */
889 		if (len == 0) {
890 			(*ilen) -= unixlen;
891 			(*instr) += unixlen;
892 			return (1);
893 		}
894 
895 		wc = 0;
896 		while(len--)
897 			wc |= (*(outp - len - 1) & 0xff) << (len << 3);
898 		return (wc);
899 	}
900 
901 	(*ilen)--;
902 	c = *(*instr)++;
903 	c = l2u[c];
904 	c = unix2dos[c];
905 	return ((u_int16_t)c);
906 }
907 
908 /*
909  * Convert Windows char to Local char
910  */
911 static u_char *
912 win2unixchr(u_char *outbuf, u_int16_t wc, struct msdosfsmount *pmp)
913 {
914 	u_char *inp, *outp, inbuf[3];
915 	size_t ilen, olen, len;
916 
917 	outp = outbuf;
918 	if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) {
919 		inbuf[0] = (u_char)(wc>>8);
920 		inbuf[1] = (u_char)wc;
921 		inbuf[2] = '\0';
922 
923 		ilen = 2;
924 		olen = len = 4;
925 		inp = inbuf;
926 		msdosfs_iconv->convchr(pmp->pm_w2u, __DECONST(const char **,
927 		    &inp), &ilen, (char **)&outp, &olen);
928 		len -= olen;
929 
930 		/*
931 		 * return '?' if failed to convert
932 		 */
933 		if (len == 0)
934 			*outp++ = '?';
935 	} else {
936 		*outp++ = (wc & 0xff00) ? '?' : (u_char)(wc & 0xff);
937 	}
938 
939 	*outp = '\0';
940 	outp = outbuf;
941 	return (outp);
942 }
943 
944 /*
945  * Convert Local char to Windows char
946  */
947 static u_int16_t
948 unix2winchr(const u_char **instr, size_t *ilen, int lower, struct msdosfsmount *pmp)
949 {
950 	u_char *outp, outbuf[3];
951 	u_int16_t wc;
952 	size_t olen;
953 
954 	if (*ilen == 0)
955 		return (0);
956 
957 	if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) {
958 		outp = outbuf;
959 		olen = 2;
960 		if (lower & (LCASE_BASE | LCASE_EXT))
961 			msdosfs_iconv->convchr_case(pmp->pm_u2w, (const char **)instr,
962 						  ilen, (char **)&outp, &olen,
963 						  KICONV_FROM_LOWER);
964 		else
965 			msdosfs_iconv->convchr(pmp->pm_u2w, (const char **)instr,
966 					     ilen, (char **)&outp, &olen);
967 
968 		/*
969 		 * return '0' if end of filename
970 		 */
971 		if (olen == 2)
972 			return (0);
973 
974 		wc = (outbuf[0]<<8) | outbuf[1];
975 
976 		return (wc);
977 	}
978 
979 	(*ilen)--;
980 	wc = (*instr)[0];
981 	if (lower & (LCASE_BASE | LCASE_EXT))
982 		wc = u2l[wc];
983 	(*instr)++;
984 	return (wc);
985 }
986 
987 /*
988  * Initialize the temporary concatenation buffer.
989  */
990 void
991 mbnambuf_init(struct mbnambuf *nbp)
992 {
993 
994 	nbp->nb_len = 0;
995 	nbp->nb_last_id = -1;
996 	nbp->nb_buf[sizeof(nbp->nb_buf) - 1] = '\0';
997 }
998 
999 /*
1000  * Fill out our concatenation buffer with the given substring, at the offset
1001  * specified by its id.  Since this function must be called with ids in
1002  * descending order, we take advantage of the fact that ASCII substrings are
1003  * exactly WIN_CHARS in length.  For non-ASCII substrings, we shift all
1004  * previous (i.e. higher id) substrings upwards to make room for this one.
1005  * This only penalizes portions of substrings that contain more than
1006  * WIN_CHARS bytes when they are first encountered.
1007  */
1008 void
1009 mbnambuf_write(struct mbnambuf *nbp, char *name, int id)
1010 {
1011 	char *slot;
1012 	size_t count, newlen;
1013 
1014 	if (nbp->nb_len != 0 && id != nbp->nb_last_id - 1) {
1015 #ifdef MSDOSFS_DEBUG
1016 		printf("msdosfs: non-decreasing id: id %d, last id %d\n",
1017 		    id, nbp->nb_last_id);
1018 #endif
1019 		return;
1020 	}
1021 
1022 	/* Will store this substring in a WIN_CHARS-aligned slot. */
1023 	slot = &nbp->nb_buf[id * WIN_CHARS];
1024 	count = strlen(name);
1025 	newlen = nbp->nb_len + count;
1026 	if (newlen > WIN_MAXLEN || newlen > MAXNAMLEN) {
1027 #ifdef MSDOSFS_DEBUG
1028 		printf("msdosfs: file name length %zu too large\n", newlen);
1029 #endif
1030 		return;
1031 	}
1032 
1033 	/* Shift suffix upwards by the amount length exceeds WIN_CHARS. */
1034 	if (count > WIN_CHARS && nbp->nb_len != 0)
1035 		bcopy(slot + WIN_CHARS, slot + count, nbp->nb_len);
1036 
1037 	/* Copy in the substring to its slot and update length so far. */
1038 	bcopy(name, slot, count);
1039 	nbp->nb_len = newlen;
1040 	nbp->nb_last_id = id;
1041 }
1042 
1043 /*
1044  * Take the completed string and use it to setup the struct dirent.
1045  * Be sure to always nul-terminate the d_name and then copy the string
1046  * from our buffer.  Note that this function assumes the full string has
1047  * been reassembled in the buffer.  If it's called before all substrings
1048  * have been written via mbnambuf_write(), the result will be incorrect.
1049  */
1050 char *
1051 mbnambuf_flush(struct mbnambuf *nbp, struct dirent *dp)
1052 {
1053 
1054 	if (nbp->nb_len > sizeof(dp->d_name) - 1) {
1055 		mbnambuf_init(nbp);
1056 		return (NULL);
1057 	}
1058 	bcopy(&nbp->nb_buf[0], dp->d_name, nbp->nb_len);
1059 	dp->d_name[nbp->nb_len] = '\0';
1060 	dp->d_namlen = nbp->nb_len;
1061 
1062 	mbnambuf_init(nbp);
1063 	return (dp->d_name);
1064 }
1065