xref: /freebsd/sys/fs/cd9660/cd9660_node.c (revision bdcbfde31e8e9b343f113a1956384bdf30d1ed62)
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 
37 #include <sys/cdefs.h>
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/mount.h>
41 #include <sys/bio.h>
42 #include <sys/buf.h>
43 #include <sys/vnode.h>
44 #include <sys/malloc.h>
45 #include <sys/stat.h>
46 #include <sys/mutex.h>
47 
48 #include <fs/cd9660/iso.h>
49 #include <fs/cd9660/cd9660_node.h>
50 #include <fs/cd9660/cd9660_mount.h>
51 
52 static unsigned	cd9660_chars2ui(unsigned char *begin, int len);
53 
54 /*
55  * Last reference to an inode, write the inode out and if necessary,
56  * truncate and deallocate the file.
57  */
58 int
59 cd9660_inactive(struct vop_inactive_args *ap)
60 {
61 	struct vnode *vp = ap->a_vp;
62 	struct iso_node *ip = VTOI(vp);
63 	int error = 0;
64 
65 	/*
66 	 * If we are done with the inode, reclaim it
67 	 * so that it can be reused immediately.
68 	 */
69 	if (ip->inode.iso_mode == 0)
70 		vrecycle(vp);
71 	return error;
72 }
73 
74 /*
75  * Reclaim an inode so that it can be used for other purposes.
76  */
77 int
78 cd9660_reclaim(struct vop_reclaim_args *ap)
79 {
80 	struct vnode *vp = ap->a_vp;
81 
82 	/*
83 	 * Remove the inode from its hash chain.
84 	 */
85 	vfs_hash_remove(vp);
86 
87 	/*
88 	 * Purge old data structures associated with the inode.
89 	 */
90 	free(vp->v_data, M_ISOFSNODE);
91 	vp->v_data = NULL;
92 	return (0);
93 }
94 
95 /*
96  * File attributes
97  */
98 void
99 cd9660_defattr(struct iso_directory_record *isodir, struct iso_node *inop,
100     struct buf *bp, enum ISO_FTYPE ftype)
101 {
102 	struct buf *bp2 = NULL;
103 	struct iso_mnt *imp;
104 	struct iso_extended_attributes *ap = NULL;
105 	int off;
106 
107 	/* high sierra does not have timezone data, flag is one byte ahead */
108 	if (isonum_711(ftype == ISO_FTYPE_HIGH_SIERRA?
109 		       &isodir->date[6]: isodir->flags)&2) {
110 		inop->inode.iso_mode = S_IFDIR;
111 		/*
112 		 * If we return 2, fts() will assume there are no subdirectories
113 		 * (just links for the path and .), so instead we return 1.
114 		 */
115 		inop->inode.iso_links = 1;
116 	} else {
117 		inop->inode.iso_mode = S_IFREG;
118 		inop->inode.iso_links = 1;
119 	}
120 	if (!bp
121 	    && ((imp = inop->i_mnt)->im_flags & ISOFSMNT_EXTATT)
122 	    && (off = isonum_711(isodir->ext_attr_length))) {
123 		cd9660_blkatoff(ITOV(inop), (off_t)-(off << imp->im_bshift), NULL,
124 			     &bp2);
125 		bp = bp2;
126 	}
127 	if (bp) {
128 		ap = (struct iso_extended_attributes *)bp->b_data;
129 
130 		if (isonum_711(ap->version) == 1) {
131 			if (!(ap->perm[0]&0x40))
132 				inop->inode.iso_mode |= S_IXOTH;
133 			if (!(ap->perm[0]&0x10))
134 				inop->inode.iso_mode |= S_IROTH;
135 			if (!(ap->perm[0]&4))
136 				inop->inode.iso_mode |= S_IXGRP;
137 			if (!(ap->perm[0]&1))
138 				inop->inode.iso_mode |= S_IRGRP;
139 			if (!(ap->perm[1]&0x40))
140 				inop->inode.iso_mode |= S_IXUSR;
141 			if (!(ap->perm[1]&0x10))
142 				inop->inode.iso_mode |= S_IRUSR;
143 			inop->inode.iso_uid = isonum_723(ap->owner); /* what about 0? */
144 			inop->inode.iso_gid = isonum_723(ap->group); /* what about 0? */
145 		} else
146 			ap = NULL;
147 	}
148 	if (!ap) {
149 		inop->inode.iso_mode |= S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH;
150 		inop->inode.iso_uid = (uid_t)0;
151 		inop->inode.iso_gid = (gid_t)0;
152 	}
153 	if (bp2)
154 		brelse(bp2);
155 }
156 
157 /*
158  * Time stamps
159  */
160 void
161 cd9660_deftstamp(struct iso_directory_record *isodir, struct iso_node *inop,
162     struct buf *bp, enum ISO_FTYPE ftype)
163 {
164 	struct buf *bp2 = NULL;
165 	struct iso_mnt *imp;
166 	struct iso_extended_attributes *ap = NULL;
167 	int off;
168 
169 	if (!bp
170 	    && ((imp = inop->i_mnt)->im_flags & ISOFSMNT_EXTATT)
171 	    && (off = isonum_711(isodir->ext_attr_length))) {
172 		cd9660_blkatoff(ITOV(inop), (off_t)-(off << imp->im_bshift), NULL,
173 			     &bp2);
174 		bp = bp2;
175 	}
176 	if (bp) {
177 		ap = (struct iso_extended_attributes *)bp->b_data;
178 
179 		if (ftype != ISO_FTYPE_HIGH_SIERRA
180 		    && isonum_711(ap->version) == 1) {
181 			if (!cd9660_tstamp_conv17(ap->ftime,&inop->inode.iso_atime))
182 				cd9660_tstamp_conv17(ap->ctime,&inop->inode.iso_atime);
183 			if (!cd9660_tstamp_conv17(ap->ctime,&inop->inode.iso_ctime))
184 				inop->inode.iso_ctime = inop->inode.iso_atime;
185 			if (!cd9660_tstamp_conv17(ap->mtime,&inop->inode.iso_mtime))
186 				inop->inode.iso_mtime = inop->inode.iso_ctime;
187 		} else
188 			ap = NULL;
189 	}
190 	if (!ap) {
191 		cd9660_tstamp_conv7(isodir->date,&inop->inode.iso_ctime,ftype);
192 		inop->inode.iso_atime = inop->inode.iso_ctime;
193 		inop->inode.iso_mtime = inop->inode.iso_ctime;
194 	}
195 	if (bp2)
196 		brelse(bp2);
197 }
198 
199 int
200 cd9660_tstamp_conv7(u_char *pi, struct timespec *pu, enum ISO_FTYPE ftype)
201 {
202 	int crtime, days;
203 	int y, m, d, hour, minute, second, tz;
204 
205 	y = pi[0] + 1900;
206 	m = pi[1];
207 	d = pi[2];
208 	hour = pi[3];
209 	minute = pi[4];
210 	second = pi[5];
211 	if(ftype != ISO_FTYPE_HIGH_SIERRA)
212 		tz = ((signed char *)pi)[6]; /* Timezone value is signed. */
213 	else
214 		/* original high sierra misses timezone data */
215 		tz = 0;
216 
217 	if (y < 1970) {
218 		pu->tv_sec  = 0;
219 		pu->tv_nsec = 0;
220 		return 0;
221 	} else {
222 #ifdef	ORIGINAL
223 		/* computes day number relative to Sept. 19th,1989 */
224 		/* don't even *THINK* about changing formula. It works! */
225 		days = 367*(y-1980)-7*(y+(m+9)/12)/4-3*((y+(m-9)/7)/100+1)/4+275*m/9+d-100;
226 #else
227 		/*
228 		 * Changed :-) to make it relative to Jan. 1st, 1970
229 		 * and to disambiguate negative division
230 		 */
231 		days = 367*(y-1960)-7*(y+(m+9)/12)/4-3*((y+(m+9)/12-1)/100+1)/4+275*m/9+d-239;
232 #endif
233 		crtime = ((((days * 24) + hour) * 60 + minute) * 60) + second;
234 
235 		/* timezone offset is unreliable on some disks */
236 		if (-48 <= tz && tz <= 52)
237 			crtime -= tz * 15 * 60;
238 	}
239 	pu->tv_sec  = crtime;
240 	pu->tv_nsec = 0;
241 	return 1;
242 }
243 
244 static u_int
245 cd9660_chars2ui(u_char *begin, int len)
246 {
247 	u_int rc;
248 
249 	for (rc = 0; --len >= 0;) {
250 		rc *= 10;
251 		rc += *begin++ - '0';
252 	}
253 	return rc;
254 }
255 
256 int
257 cd9660_tstamp_conv17(u_char *pi, struct timespec *pu)
258 {
259 	u_char buf[7];
260 
261 	/* year:"0001"-"9999" -> -1900  */
262 	buf[0] = cd9660_chars2ui(pi,4) - 1900;
263 
264 	/* month: " 1"-"12"   -> 1 - 12 */
265 	buf[1] = cd9660_chars2ui(pi + 4,2);
266 
267 	/* day:	  " 1"-"31"   -> 1 - 31 */
268 	buf[2] = cd9660_chars2ui(pi + 6,2);
269 
270 	/* hour:  " 0"-"23"   -> 0 - 23 */
271 	buf[3] = cd9660_chars2ui(pi + 8,2);
272 
273 	/* minute:" 0"-"59"   -> 0 - 59 */
274 	buf[4] = cd9660_chars2ui(pi + 10,2);
275 
276 	/* second:" 0"-"59"   -> 0 - 59 */
277 	buf[5] = cd9660_chars2ui(pi + 12,2);
278 
279 	/* difference of GMT */
280 	buf[6] = pi[16];
281 
282 	return cd9660_tstamp_conv7(buf, pu, ISO_FTYPE_DEFAULT);
283 }
284 
285 cd_ino_t
286 isodirino(struct iso_directory_record *isodir, struct iso_mnt *imp)
287 {
288 	cd_ino_t ino;
289 
290 	/*
291 	 * Note there is an inverse calculation in
292 	 * cd9660_vfsops.c:cd9660_vget_internal():
293 	 *   ip->iso_start = ino >> imp->im_bshift;
294 	 * and also a calculation of the isodir pointer
295 	 * from an inode in cd9660_vnops.c:cd9660_readlink()
296 	 */
297 	ino = ((cd_ino_t)isonum_733(isodir->extent) +
298 		isonum_711(isodir->ext_attr_length)) << imp->im_bshift;
299 	return ino;
300 }
301