xref: /freebsd/sys/fs/cd9660/cd9660_node.c (revision 1d386b48)
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 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/mount.h>
43 #include <sys/bio.h>
44 #include <sys/buf.h>
45 #include <sys/vnode.h>
46 #include <sys/malloc.h>
47 #include <sys/stat.h>
48 #include <sys/mutex.h>
49 
50 #include <fs/cd9660/iso.h>
51 #include <fs/cd9660/cd9660_node.h>
52 #include <fs/cd9660/cd9660_mount.h>
53 
54 static unsigned	cd9660_chars2ui(unsigned char *begin, int len);
55 
56 /*
57  * Last reference to an inode, write the inode out and if necessary,
58  * truncate and deallocate the file.
59  */
60 int
61 cd9660_inactive(struct vop_inactive_args *ap)
62 {
63 	struct vnode *vp = ap->a_vp;
64 	struct iso_node *ip = VTOI(vp);
65 	int error = 0;
66 
67 	/*
68 	 * If we are done with the inode, reclaim it
69 	 * so that it can be reused immediately.
70 	 */
71 	if (ip->inode.iso_mode == 0)
72 		vrecycle(vp);
73 	return error;
74 }
75 
76 /*
77  * Reclaim an inode so that it can be used for other purposes.
78  */
79 int
80 cd9660_reclaim(struct vop_reclaim_args *ap)
81 {
82 	struct vnode *vp = ap->a_vp;
83 
84 	/*
85 	 * Remove the inode from its hash chain.
86 	 */
87 	vfs_hash_remove(vp);
88 
89 	/*
90 	 * Purge old data structures associated with the inode.
91 	 */
92 	free(vp->v_data, M_ISOFSNODE);
93 	vp->v_data = NULL;
94 	return (0);
95 }
96 
97 /*
98  * File attributes
99  */
100 void
101 cd9660_defattr(struct iso_directory_record *isodir, struct iso_node *inop,
102     struct buf *bp, enum ISO_FTYPE ftype)
103 {
104 	struct buf *bp2 = NULL;
105 	struct iso_mnt *imp;
106 	struct iso_extended_attributes *ap = NULL;
107 	int off;
108 
109 	/* high sierra does not have timezone data, flag is one byte ahead */
110 	if (isonum_711(ftype == ISO_FTYPE_HIGH_SIERRA?
111 		       &isodir->date[6]: isodir->flags)&2) {
112 		inop->inode.iso_mode = S_IFDIR;
113 		/*
114 		 * If we return 2, fts() will assume there are no subdirectories
115 		 * (just links for the path and .), so instead we return 1.
116 		 */
117 		inop->inode.iso_links = 1;
118 	} else {
119 		inop->inode.iso_mode = S_IFREG;
120 		inop->inode.iso_links = 1;
121 	}
122 	if (!bp
123 	    && ((imp = inop->i_mnt)->im_flags & ISOFSMNT_EXTATT)
124 	    && (off = isonum_711(isodir->ext_attr_length))) {
125 		cd9660_blkatoff(ITOV(inop), (off_t)-(off << imp->im_bshift), NULL,
126 			     &bp2);
127 		bp = bp2;
128 	}
129 	if (bp) {
130 		ap = (struct iso_extended_attributes *)bp->b_data;
131 
132 		if (isonum_711(ap->version) == 1) {
133 			if (!(ap->perm[0]&0x40))
134 				inop->inode.iso_mode |= S_IXOTH;
135 			if (!(ap->perm[0]&0x10))
136 				inop->inode.iso_mode |= S_IROTH;
137 			if (!(ap->perm[0]&4))
138 				inop->inode.iso_mode |= S_IXGRP;
139 			if (!(ap->perm[0]&1))
140 				inop->inode.iso_mode |= S_IRGRP;
141 			if (!(ap->perm[1]&0x40))
142 				inop->inode.iso_mode |= S_IXUSR;
143 			if (!(ap->perm[1]&0x10))
144 				inop->inode.iso_mode |= S_IRUSR;
145 			inop->inode.iso_uid = isonum_723(ap->owner); /* what about 0? */
146 			inop->inode.iso_gid = isonum_723(ap->group); /* what about 0? */
147 		} else
148 			ap = NULL;
149 	}
150 	if (!ap) {
151 		inop->inode.iso_mode |= S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH;
152 		inop->inode.iso_uid = (uid_t)0;
153 		inop->inode.iso_gid = (gid_t)0;
154 	}
155 	if (bp2)
156 		brelse(bp2);
157 }
158 
159 /*
160  * Time stamps
161  */
162 void
163 cd9660_deftstamp(struct iso_directory_record *isodir, struct iso_node *inop,
164     struct buf *bp, enum ISO_FTYPE ftype)
165 {
166 	struct buf *bp2 = NULL;
167 	struct iso_mnt *imp;
168 	struct iso_extended_attributes *ap = NULL;
169 	int off;
170 
171 	if (!bp
172 	    && ((imp = inop->i_mnt)->im_flags & ISOFSMNT_EXTATT)
173 	    && (off = isonum_711(isodir->ext_attr_length))) {
174 		cd9660_blkatoff(ITOV(inop), (off_t)-(off << imp->im_bshift), NULL,
175 			     &bp2);
176 		bp = bp2;
177 	}
178 	if (bp) {
179 		ap = (struct iso_extended_attributes *)bp->b_data;
180 
181 		if (ftype != ISO_FTYPE_HIGH_SIERRA
182 		    && isonum_711(ap->version) == 1) {
183 			if (!cd9660_tstamp_conv17(ap->ftime,&inop->inode.iso_atime))
184 				cd9660_tstamp_conv17(ap->ctime,&inop->inode.iso_atime);
185 			if (!cd9660_tstamp_conv17(ap->ctime,&inop->inode.iso_ctime))
186 				inop->inode.iso_ctime = inop->inode.iso_atime;
187 			if (!cd9660_tstamp_conv17(ap->mtime,&inop->inode.iso_mtime))
188 				inop->inode.iso_mtime = inop->inode.iso_ctime;
189 		} else
190 			ap = NULL;
191 	}
192 	if (!ap) {
193 		cd9660_tstamp_conv7(isodir->date,&inop->inode.iso_ctime,ftype);
194 		inop->inode.iso_atime = inop->inode.iso_ctime;
195 		inop->inode.iso_mtime = inop->inode.iso_ctime;
196 	}
197 	if (bp2)
198 		brelse(bp2);
199 }
200 
201 int
202 cd9660_tstamp_conv7(u_char *pi, struct timespec *pu, enum ISO_FTYPE ftype)
203 {
204 	int crtime, days;
205 	int y, m, d, hour, minute, second, tz;
206 
207 	y = pi[0] + 1900;
208 	m = pi[1];
209 	d = pi[2];
210 	hour = pi[3];
211 	minute = pi[4];
212 	second = pi[5];
213 	if(ftype != ISO_FTYPE_HIGH_SIERRA)
214 		tz = ((signed char *)pi)[6]; /* Timezone value is signed. */
215 	else
216 		/* original high sierra misses timezone data */
217 		tz = 0;
218 
219 	if (y < 1970) {
220 		pu->tv_sec  = 0;
221 		pu->tv_nsec = 0;
222 		return 0;
223 	} else {
224 #ifdef	ORIGINAL
225 		/* computes day number relative to Sept. 19th,1989 */
226 		/* don't even *THINK* about changing formula. It works! */
227 		days = 367*(y-1980)-7*(y+(m+9)/12)/4-3*((y+(m-9)/7)/100+1)/4+275*m/9+d-100;
228 #else
229 		/*
230 		 * Changed :-) to make it relative to Jan. 1st, 1970
231 		 * and to disambiguate negative division
232 		 */
233 		days = 367*(y-1960)-7*(y+(m+9)/12)/4-3*((y+(m+9)/12-1)/100+1)/4+275*m/9+d-239;
234 #endif
235 		crtime = ((((days * 24) + hour) * 60 + minute) * 60) + second;
236 
237 		/* timezone offset is unreliable on some disks */
238 		if (-48 <= tz && tz <= 52)
239 			crtime -= tz * 15 * 60;
240 	}
241 	pu->tv_sec  = crtime;
242 	pu->tv_nsec = 0;
243 	return 1;
244 }
245 
246 static u_int
247 cd9660_chars2ui(u_char *begin, int len)
248 {
249 	u_int rc;
250 
251 	for (rc = 0; --len >= 0;) {
252 		rc *= 10;
253 		rc += *begin++ - '0';
254 	}
255 	return rc;
256 }
257 
258 int
259 cd9660_tstamp_conv17(u_char *pi, struct timespec *pu)
260 {
261 	u_char buf[7];
262 
263 	/* year:"0001"-"9999" -> -1900  */
264 	buf[0] = cd9660_chars2ui(pi,4) - 1900;
265 
266 	/* month: " 1"-"12"   -> 1 - 12 */
267 	buf[1] = cd9660_chars2ui(pi + 4,2);
268 
269 	/* day:	  " 1"-"31"   -> 1 - 31 */
270 	buf[2] = cd9660_chars2ui(pi + 6,2);
271 
272 	/* hour:  " 0"-"23"   -> 0 - 23 */
273 	buf[3] = cd9660_chars2ui(pi + 8,2);
274 
275 	/* minute:" 0"-"59"   -> 0 - 59 */
276 	buf[4] = cd9660_chars2ui(pi + 10,2);
277 
278 	/* second:" 0"-"59"   -> 0 - 59 */
279 	buf[5] = cd9660_chars2ui(pi + 12,2);
280 
281 	/* difference of GMT */
282 	buf[6] = pi[16];
283 
284 	return cd9660_tstamp_conv7(buf, pu, ISO_FTYPE_DEFAULT);
285 }
286 
287 cd_ino_t
288 isodirino(struct iso_directory_record *isodir, struct iso_mnt *imp)
289 {
290 	cd_ino_t ino;
291 
292 	/*
293 	 * Note there is an inverse calculation in
294 	 * cd9660_vfsops.c:cd9660_vget_internal():
295 	 *   ip->iso_start = ino >> imp->im_bshift;
296 	 * and also a calculation of the isodir pointer
297 	 * from an inode in cd9660_vnops.c:cd9660_readlink()
298 	 */
299 	ino = ((cd_ino_t)isonum_733(isodir->extent) +
300 		isonum_711(isodir->ext_attr_length)) << imp->im_bshift;
301 	return ino;
302 }
303