xref: /freebsd/sys/fs/cd9660/cd9660_node.c (revision 9e5787d2284e187abb5b654d924394a65772e004)
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(ap)
64 	struct vop_inactive_args /* {
65 		struct vnode *a_vp;
66 		struct thread *a_td;
67 	} */ *ap;
68 {
69 	struct vnode *vp = ap->a_vp;
70 	struct iso_node *ip = VTOI(vp);
71 	int error = 0;
72 
73 	/*
74 	 * If we are done with the inode, reclaim it
75 	 * so that it can be reused immediately.
76 	 */
77 	if (ip->inode.iso_mode == 0)
78 		vrecycle(vp);
79 	return error;
80 }
81 
82 /*
83  * Reclaim an inode so that it can be used for other purposes.
84  */
85 int
86 cd9660_reclaim(ap)
87 	struct vop_reclaim_args /* {
88 		struct vnode *a_vp;
89 	} */ *ap;
90 {
91 	struct vnode *vp = ap->a_vp;
92 
93 	/*
94 	 * Remove the inode from its hash chain.
95 	 */
96 	vfs_hash_remove(vp);
97 
98 	/*
99 	 * Purge old data structures associated with the inode.
100 	 */
101 	free(vp->v_data, M_ISOFSNODE);
102 	vp->v_data = NULL;
103 	return (0);
104 }
105 
106 /*
107  * File attributes
108  */
109 void
110 cd9660_defattr(isodir, inop, bp, ftype)
111 	struct iso_directory_record *isodir;
112 	struct iso_node *inop;
113 	struct buf *bp;
114 	enum ISO_FTYPE ftype;
115 {
116 	struct buf *bp2 = NULL;
117 	struct iso_mnt *imp;
118 	struct iso_extended_attributes *ap = NULL;
119 	int off;
120 
121 	/* high sierra does not have timezone data, flag is one byte ahead */
122 	if (isonum_711(ftype == ISO_FTYPE_HIGH_SIERRA?
123 		       &isodir->date[6]: isodir->flags)&2) {
124 		inop->inode.iso_mode = S_IFDIR;
125 		/*
126 		 * If we return 2, fts() will assume there are no subdirectories
127 		 * (just links for the path and .), so instead we return 1.
128 		 */
129 		inop->inode.iso_links = 1;
130 	} else {
131 		inop->inode.iso_mode = S_IFREG;
132 		inop->inode.iso_links = 1;
133 	}
134 	if (!bp
135 	    && ((imp = inop->i_mnt)->im_flags & ISOFSMNT_EXTATT)
136 	    && (off = isonum_711(isodir->ext_attr_length))) {
137 		cd9660_blkatoff(ITOV(inop), (off_t)-(off << imp->im_bshift), NULL,
138 			     &bp2);
139 		bp = bp2;
140 	}
141 	if (bp) {
142 		ap = (struct iso_extended_attributes *)bp->b_data;
143 
144 		if (isonum_711(ap->version) == 1) {
145 			if (!(ap->perm[0]&0x40))
146 				inop->inode.iso_mode |= S_IXOTH;
147 			if (!(ap->perm[0]&0x10))
148 				inop->inode.iso_mode |= S_IROTH;
149 			if (!(ap->perm[0]&4))
150 				inop->inode.iso_mode |= S_IXGRP;
151 			if (!(ap->perm[0]&1))
152 				inop->inode.iso_mode |= S_IRGRP;
153 			if (!(ap->perm[1]&0x40))
154 				inop->inode.iso_mode |= S_IXUSR;
155 			if (!(ap->perm[1]&0x10))
156 				inop->inode.iso_mode |= S_IRUSR;
157 			inop->inode.iso_uid = isonum_723(ap->owner); /* what about 0? */
158 			inop->inode.iso_gid = isonum_723(ap->group); /* what about 0? */
159 		} else
160 			ap = NULL;
161 	}
162 	if (!ap) {
163 		inop->inode.iso_mode |= S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH;
164 		inop->inode.iso_uid = (uid_t)0;
165 		inop->inode.iso_gid = (gid_t)0;
166 	}
167 	if (bp2)
168 		brelse(bp2);
169 }
170 
171 /*
172  * Time stamps
173  */
174 void
175 cd9660_deftstamp(isodir,inop,bp,ftype)
176 	struct iso_directory_record *isodir;
177 	struct iso_node *inop;
178 	struct buf *bp;
179 	enum ISO_FTYPE ftype;
180 {
181 	struct buf *bp2 = NULL;
182 	struct iso_mnt *imp;
183 	struct iso_extended_attributes *ap = NULL;
184 	int off;
185 
186 	if (!bp
187 	    && ((imp = inop->i_mnt)->im_flags & ISOFSMNT_EXTATT)
188 	    && (off = isonum_711(isodir->ext_attr_length))) {
189 		cd9660_blkatoff(ITOV(inop), (off_t)-(off << imp->im_bshift), NULL,
190 			     &bp2);
191 		bp = bp2;
192 	}
193 	if (bp) {
194 		ap = (struct iso_extended_attributes *)bp->b_data;
195 
196 		if (ftype != ISO_FTYPE_HIGH_SIERRA
197 		    && isonum_711(ap->version) == 1) {
198 			if (!cd9660_tstamp_conv17(ap->ftime,&inop->inode.iso_atime))
199 				cd9660_tstamp_conv17(ap->ctime,&inop->inode.iso_atime);
200 			if (!cd9660_tstamp_conv17(ap->ctime,&inop->inode.iso_ctime))
201 				inop->inode.iso_ctime = inop->inode.iso_atime;
202 			if (!cd9660_tstamp_conv17(ap->mtime,&inop->inode.iso_mtime))
203 				inop->inode.iso_mtime = inop->inode.iso_ctime;
204 		} else
205 			ap = NULL;
206 	}
207 	if (!ap) {
208 		cd9660_tstamp_conv7(isodir->date,&inop->inode.iso_ctime,ftype);
209 		inop->inode.iso_atime = inop->inode.iso_ctime;
210 		inop->inode.iso_mtime = inop->inode.iso_ctime;
211 	}
212 	if (bp2)
213 		brelse(bp2);
214 }
215 
216 int
217 cd9660_tstamp_conv7(pi,pu,ftype)
218 	u_char *pi;
219 	struct timespec *pu;
220 	enum ISO_FTYPE ftype;
221 {
222 	int crtime, days;
223 	int y, m, d, hour, minute, second, tz;
224 
225 	y = pi[0] + 1900;
226 	m = pi[1];
227 	d = pi[2];
228 	hour = pi[3];
229 	minute = pi[4];
230 	second = pi[5];
231 	if(ftype != ISO_FTYPE_HIGH_SIERRA)
232 		tz = ((signed char *)pi)[6]; /* Timezone value is signed. */
233 	else
234 		/* original high sierra misses timezone data */
235 		tz = 0;
236 
237 	if (y < 1970) {
238 		pu->tv_sec  = 0;
239 		pu->tv_nsec = 0;
240 		return 0;
241 	} else {
242 #ifdef	ORIGINAL
243 		/* computes day number relative to Sept. 19th,1989 */
244 		/* don't even *THINK* about changing formula. It works! */
245 		days = 367*(y-1980)-7*(y+(m+9)/12)/4-3*((y+(m-9)/7)/100+1)/4+275*m/9+d-100;
246 #else
247 		/*
248 		 * Changed :-) to make it relative to Jan. 1st, 1970
249 		 * and to disambiguate negative division
250 		 */
251 		days = 367*(y-1960)-7*(y+(m+9)/12)/4-3*((y+(m+9)/12-1)/100+1)/4+275*m/9+d-239;
252 #endif
253 		crtime = ((((days * 24) + hour) * 60 + minute) * 60) + second;
254 
255 		/* timezone offset is unreliable on some disks */
256 		if (-48 <= tz && tz <= 52)
257 			crtime -= tz * 15 * 60;
258 	}
259 	pu->tv_sec  = crtime;
260 	pu->tv_nsec = 0;
261 	return 1;
262 }
263 
264 static u_int
265 cd9660_chars2ui(begin,len)
266 	u_char *begin;
267 	int len;
268 {
269 	u_int rc;
270 
271 	for (rc = 0; --len >= 0;) {
272 		rc *= 10;
273 		rc += *begin++ - '0';
274 	}
275 	return rc;
276 }
277 
278 int
279 cd9660_tstamp_conv17(pi,pu)
280 	u_char *pi;
281 	struct timespec *pu;
282 {
283 	u_char buf[7];
284 
285 	/* year:"0001"-"9999" -> -1900  */
286 	buf[0] = cd9660_chars2ui(pi,4) - 1900;
287 
288 	/* month: " 1"-"12"   -> 1 - 12 */
289 	buf[1] = cd9660_chars2ui(pi + 4,2);
290 
291 	/* day:	  " 1"-"31"   -> 1 - 31 */
292 	buf[2] = cd9660_chars2ui(pi + 6,2);
293 
294 	/* hour:  " 0"-"23"   -> 0 - 23 */
295 	buf[3] = cd9660_chars2ui(pi + 8,2);
296 
297 	/* minute:" 0"-"59"   -> 0 - 59 */
298 	buf[4] = cd9660_chars2ui(pi + 10,2);
299 
300 	/* second:" 0"-"59"   -> 0 - 59 */
301 	buf[5] = cd9660_chars2ui(pi + 12,2);
302 
303 	/* difference of GMT */
304 	buf[6] = pi[16];
305 
306 	return cd9660_tstamp_conv7(buf, pu, ISO_FTYPE_DEFAULT);
307 }
308 
309 cd_ino_t
310 isodirino(isodir, imp)
311 	struct iso_directory_record *isodir;
312 	struct iso_mnt *imp;
313 {
314 	cd_ino_t ino;
315 
316 	/*
317 	 * Note there is an inverse calculation in
318 	 * cd9660_vfsops.c:cd9660_vget_internal():
319 	 *   ip->iso_start = ino >> imp->im_bshift;
320 	 * and also a calculation of the isodir pointer
321 	 * from an inode in cd9660_vnops.c:cd9660_readlink()
322 	 */
323 	ino = ((cd_ino_t)isonum_733(isodir->extent) +
324 		isonum_711(isodir->ext_attr_length)) << imp->im_bshift;
325 	return ino;
326 }
327