xref: /freebsd/sys/fs/cd9660/cd9660_node.c (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1982, 1986, 1989, 1994, 1995
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley
8  * by Pace Willisson (pace@blitz.com).  The Rock Ridge Extension
9  * Support code is derived from software contributed to Berkeley
10  * by Atsushi Murai (amurai@spec.co.jp).
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)cd9660_node.c	8.2 (Berkeley) 1/23/94
37  */
38 
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41 
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/mount.h>
45 #include <sys/bio.h>
46 #include <sys/buf.h>
47 #include <sys/vnode.h>
48 #include <sys/malloc.h>
49 #include <sys/stat.h>
50 #include <sys/mutex.h>
51 
52 #include <fs/cd9660/iso.h>
53 #include <fs/cd9660/cd9660_node.h>
54 #include <fs/cd9660/cd9660_mount.h>
55 
56 static unsigned	cd9660_chars2ui(unsigned char *begin, int len);
57 
58 /*
59  * Last reference to an inode, write the inode out and if necessary,
60  * truncate and deallocate the file.
61  */
62 int
63 cd9660_inactive(struct vop_inactive_args *ap)
64 {
65 	struct vnode *vp = ap->a_vp;
66 	struct iso_node *ip = VTOI(vp);
67 	int error = 0;
68 
69 	/*
70 	 * If we are done with the inode, reclaim it
71 	 * so that it can be reused immediately.
72 	 */
73 	if (ip->inode.iso_mode == 0)
74 		vrecycle(vp);
75 	return error;
76 }
77 
78 /*
79  * Reclaim an inode so that it can be used for other purposes.
80  */
81 int
82 cd9660_reclaim(struct vop_reclaim_args *ap)
83 {
84 	struct vnode *vp = ap->a_vp;
85 
86 	/*
87 	 * Remove the inode from its hash chain.
88 	 */
89 	vfs_hash_remove(vp);
90 
91 	/*
92 	 * Purge old data structures associated with the inode.
93 	 */
94 	free(vp->v_data, M_ISOFSNODE);
95 	vp->v_data = NULL;
96 	return (0);
97 }
98 
99 /*
100  * File attributes
101  */
102 void
103 cd9660_defattr(struct iso_directory_record *isodir, struct iso_node *inop,
104     struct buf *bp, enum ISO_FTYPE ftype)
105 {
106 	struct buf *bp2 = NULL;
107 	struct iso_mnt *imp;
108 	struct iso_extended_attributes *ap = NULL;
109 	int off;
110 
111 	/* high sierra does not have timezone data, flag is one byte ahead */
112 	if (isonum_711(ftype == ISO_FTYPE_HIGH_SIERRA?
113 		       &isodir->date[6]: isodir->flags)&2) {
114 		inop->inode.iso_mode = S_IFDIR;
115 		/*
116 		 * If we return 2, fts() will assume there are no subdirectories
117 		 * (just links for the path and .), so instead we return 1.
118 		 */
119 		inop->inode.iso_links = 1;
120 	} else {
121 		inop->inode.iso_mode = S_IFREG;
122 		inop->inode.iso_links = 1;
123 	}
124 	if (!bp
125 	    && ((imp = inop->i_mnt)->im_flags & ISOFSMNT_EXTATT)
126 	    && (off = isonum_711(isodir->ext_attr_length))) {
127 		cd9660_blkatoff(ITOV(inop), (off_t)-(off << imp->im_bshift), NULL,
128 			     &bp2);
129 		bp = bp2;
130 	}
131 	if (bp) {
132 		ap = (struct iso_extended_attributes *)bp->b_data;
133 
134 		if (isonum_711(ap->version) == 1) {
135 			if (!(ap->perm[0]&0x40))
136 				inop->inode.iso_mode |= S_IXOTH;
137 			if (!(ap->perm[0]&0x10))
138 				inop->inode.iso_mode |= S_IROTH;
139 			if (!(ap->perm[0]&4))
140 				inop->inode.iso_mode |= S_IXGRP;
141 			if (!(ap->perm[0]&1))
142 				inop->inode.iso_mode |= S_IRGRP;
143 			if (!(ap->perm[1]&0x40))
144 				inop->inode.iso_mode |= S_IXUSR;
145 			if (!(ap->perm[1]&0x10))
146 				inop->inode.iso_mode |= S_IRUSR;
147 			inop->inode.iso_uid = isonum_723(ap->owner); /* what about 0? */
148 			inop->inode.iso_gid = isonum_723(ap->group); /* what about 0? */
149 		} else
150 			ap = NULL;
151 	}
152 	if (!ap) {
153 		inop->inode.iso_mode |= S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH;
154 		inop->inode.iso_uid = (uid_t)0;
155 		inop->inode.iso_gid = (gid_t)0;
156 	}
157 	if (bp2)
158 		brelse(bp2);
159 }
160 
161 /*
162  * Time stamps
163  */
164 void
165 cd9660_deftstamp(struct iso_directory_record *isodir, struct iso_node *inop,
166     struct buf *bp, enum ISO_FTYPE ftype)
167 {
168 	struct buf *bp2 = NULL;
169 	struct iso_mnt *imp;
170 	struct iso_extended_attributes *ap = NULL;
171 	int off;
172 
173 	if (!bp
174 	    && ((imp = inop->i_mnt)->im_flags & ISOFSMNT_EXTATT)
175 	    && (off = isonum_711(isodir->ext_attr_length))) {
176 		cd9660_blkatoff(ITOV(inop), (off_t)-(off << imp->im_bshift), NULL,
177 			     &bp2);
178 		bp = bp2;
179 	}
180 	if (bp) {
181 		ap = (struct iso_extended_attributes *)bp->b_data;
182 
183 		if (ftype != ISO_FTYPE_HIGH_SIERRA
184 		    && isonum_711(ap->version) == 1) {
185 			if (!cd9660_tstamp_conv17(ap->ftime,&inop->inode.iso_atime))
186 				cd9660_tstamp_conv17(ap->ctime,&inop->inode.iso_atime);
187 			if (!cd9660_tstamp_conv17(ap->ctime,&inop->inode.iso_ctime))
188 				inop->inode.iso_ctime = inop->inode.iso_atime;
189 			if (!cd9660_tstamp_conv17(ap->mtime,&inop->inode.iso_mtime))
190 				inop->inode.iso_mtime = inop->inode.iso_ctime;
191 		} else
192 			ap = NULL;
193 	}
194 	if (!ap) {
195 		cd9660_tstamp_conv7(isodir->date,&inop->inode.iso_ctime,ftype);
196 		inop->inode.iso_atime = inop->inode.iso_ctime;
197 		inop->inode.iso_mtime = inop->inode.iso_ctime;
198 	}
199 	if (bp2)
200 		brelse(bp2);
201 }
202 
203 int
204 cd9660_tstamp_conv7(u_char *pi, struct timespec *pu, enum ISO_FTYPE ftype)
205 {
206 	int crtime, days;
207 	int y, m, d, hour, minute, second, tz;
208 
209 	y = pi[0] + 1900;
210 	m = pi[1];
211 	d = pi[2];
212 	hour = pi[3];
213 	minute = pi[4];
214 	second = pi[5];
215 	if(ftype != ISO_FTYPE_HIGH_SIERRA)
216 		tz = ((signed char *)pi)[6]; /* Timezone value is signed. */
217 	else
218 		/* original high sierra misses timezone data */
219 		tz = 0;
220 
221 	if (y < 1970) {
222 		pu->tv_sec  = 0;
223 		pu->tv_nsec = 0;
224 		return 0;
225 	} else {
226 #ifdef	ORIGINAL
227 		/* computes day number relative to Sept. 19th,1989 */
228 		/* don't even *THINK* about changing formula. It works! */
229 		days = 367*(y-1980)-7*(y+(m+9)/12)/4-3*((y+(m-9)/7)/100+1)/4+275*m/9+d-100;
230 #else
231 		/*
232 		 * Changed :-) to make it relative to Jan. 1st, 1970
233 		 * and to disambiguate negative division
234 		 */
235 		days = 367*(y-1960)-7*(y+(m+9)/12)/4-3*((y+(m+9)/12-1)/100+1)/4+275*m/9+d-239;
236 #endif
237 		crtime = ((((days * 24) + hour) * 60 + minute) * 60) + second;
238 
239 		/* timezone offset is unreliable on some disks */
240 		if (-48 <= tz && tz <= 52)
241 			crtime -= tz * 15 * 60;
242 	}
243 	pu->tv_sec  = crtime;
244 	pu->tv_nsec = 0;
245 	return 1;
246 }
247 
248 static u_int
249 cd9660_chars2ui(u_char *begin, int len)
250 {
251 	u_int rc;
252 
253 	for (rc = 0; --len >= 0;) {
254 		rc *= 10;
255 		rc += *begin++ - '0';
256 	}
257 	return rc;
258 }
259 
260 int
261 cd9660_tstamp_conv17(u_char *pi, struct timespec *pu)
262 {
263 	u_char buf[7];
264 
265 	/* year:"0001"-"9999" -> -1900  */
266 	buf[0] = cd9660_chars2ui(pi,4) - 1900;
267 
268 	/* month: " 1"-"12"   -> 1 - 12 */
269 	buf[1] = cd9660_chars2ui(pi + 4,2);
270 
271 	/* day:	  " 1"-"31"   -> 1 - 31 */
272 	buf[2] = cd9660_chars2ui(pi + 6,2);
273 
274 	/* hour:  " 0"-"23"   -> 0 - 23 */
275 	buf[3] = cd9660_chars2ui(pi + 8,2);
276 
277 	/* minute:" 0"-"59"   -> 0 - 59 */
278 	buf[4] = cd9660_chars2ui(pi + 10,2);
279 
280 	/* second:" 0"-"59"   -> 0 - 59 */
281 	buf[5] = cd9660_chars2ui(pi + 12,2);
282 
283 	/* difference of GMT */
284 	buf[6] = pi[16];
285 
286 	return cd9660_tstamp_conv7(buf, pu, ISO_FTYPE_DEFAULT);
287 }
288 
289 cd_ino_t
290 isodirino(struct iso_directory_record *isodir, struct iso_mnt *imp)
291 {
292 	cd_ino_t ino;
293 
294 	/*
295 	 * Note there is an inverse calculation in
296 	 * cd9660_vfsops.c:cd9660_vget_internal():
297 	 *   ip->iso_start = ino >> imp->im_bshift;
298 	 * and also a calculation of the isodir pointer
299 	 * from an inode in cd9660_vnops.c:cd9660_readlink()
300 	 */
301 	ino = ((cd_ino_t)isonum_733(isodir->extent) +
302 		isonum_711(isodir->ext_attr_length)) << imp->im_bshift;
303 	return ino;
304 }
305