xref: /freebsd/sys/fs/cd9660/cd9660_node.c (revision fdafd315ad0d0f28a11b9fb4476a9ab059c62b92)
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/param.h>
38 #include <sys/systm.h>
39 #include <sys/mount.h>
40 #include <sys/bio.h>
41 #include <sys/buf.h>
42 #include <sys/vnode.h>
43 #include <sys/malloc.h>
44 #include <sys/stat.h>
45 #include <sys/mutex.h>
46 
47 #include <fs/cd9660/iso.h>
48 #include <fs/cd9660/cd9660_node.h>
49 #include <fs/cd9660/cd9660_mount.h>
50 
51 static unsigned	cd9660_chars2ui(unsigned char *begin, int len);
52 
53 /*
54  * Last reference to an inode, write the inode out and if necessary,
55  * truncate and deallocate the file.
56  */
57 int
cd9660_inactive(struct vop_inactive_args * ap)58 cd9660_inactive(struct vop_inactive_args *ap)
59 {
60 	struct vnode *vp = ap->a_vp;
61 	struct iso_node *ip = VTOI(vp);
62 	int error = 0;
63 
64 	/*
65 	 * If we are done with the inode, reclaim it
66 	 * so that it can be reused immediately.
67 	 */
68 	if (ip->inode.iso_mode == 0)
69 		vrecycle(vp);
70 	return error;
71 }
72 
73 /*
74  * Reclaim an inode so that it can be used for other purposes.
75  */
76 int
cd9660_reclaim(struct vop_reclaim_args * ap)77 cd9660_reclaim(struct vop_reclaim_args *ap)
78 {
79 	struct vnode *vp = ap->a_vp;
80 
81 	/*
82 	 * Remove the inode from its hash chain.
83 	 */
84 	vfs_hash_remove(vp);
85 
86 	/*
87 	 * Purge old data structures associated with the inode.
88 	 */
89 	free(vp->v_data, M_ISOFSNODE);
90 	vp->v_data = NULL;
91 	return (0);
92 }
93 
94 /*
95  * File attributes
96  */
97 void
cd9660_defattr(struct iso_directory_record * isodir,struct iso_node * inop,struct buf * bp,enum ISO_FTYPE ftype)98 cd9660_defattr(struct iso_directory_record *isodir, struct iso_node *inop,
99     struct buf *bp, enum ISO_FTYPE ftype)
100 {
101 	struct buf *bp2 = NULL;
102 	struct iso_mnt *imp;
103 	struct iso_extended_attributes *ap = NULL;
104 	int off;
105 
106 	/* high sierra does not have timezone data, flag is one byte ahead */
107 	if (isonum_711(ftype == ISO_FTYPE_HIGH_SIERRA?
108 		       &isodir->date[6]: isodir->flags)&2) {
109 		inop->inode.iso_mode = S_IFDIR;
110 		/*
111 		 * If we return 2, fts() will assume there are no subdirectories
112 		 * (just links for the path and .), so instead we return 1.
113 		 */
114 		inop->inode.iso_links = 1;
115 	} else {
116 		inop->inode.iso_mode = S_IFREG;
117 		inop->inode.iso_links = 1;
118 	}
119 	if (!bp
120 	    && ((imp = inop->i_mnt)->im_flags & ISOFSMNT_EXTATT)
121 	    && (off = isonum_711(isodir->ext_attr_length))) {
122 		cd9660_blkatoff(ITOV(inop), (off_t)-(off << imp->im_bshift), NULL,
123 			     &bp2);
124 		bp = bp2;
125 	}
126 	if (bp) {
127 		ap = (struct iso_extended_attributes *)bp->b_data;
128 
129 		if (isonum_711(ap->version) == 1) {
130 			if (!(ap->perm[0]&0x40))
131 				inop->inode.iso_mode |= S_IXOTH;
132 			if (!(ap->perm[0]&0x10))
133 				inop->inode.iso_mode |= S_IROTH;
134 			if (!(ap->perm[0]&4))
135 				inop->inode.iso_mode |= S_IXGRP;
136 			if (!(ap->perm[0]&1))
137 				inop->inode.iso_mode |= S_IRGRP;
138 			if (!(ap->perm[1]&0x40))
139 				inop->inode.iso_mode |= S_IXUSR;
140 			if (!(ap->perm[1]&0x10))
141 				inop->inode.iso_mode |= S_IRUSR;
142 			inop->inode.iso_uid = isonum_723(ap->owner); /* what about 0? */
143 			inop->inode.iso_gid = isonum_723(ap->group); /* what about 0? */
144 		} else
145 			ap = NULL;
146 	}
147 	if (!ap) {
148 		inop->inode.iso_mode |= S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH;
149 		inop->inode.iso_uid = (uid_t)0;
150 		inop->inode.iso_gid = (gid_t)0;
151 	}
152 	if (bp2)
153 		brelse(bp2);
154 }
155 
156 /*
157  * Time stamps
158  */
159 void
cd9660_deftstamp(struct iso_directory_record * isodir,struct iso_node * inop,struct buf * bp,enum ISO_FTYPE ftype)160 cd9660_deftstamp(struct iso_directory_record *isodir, struct iso_node *inop,
161     struct buf *bp, enum ISO_FTYPE ftype)
162 {
163 	struct buf *bp2 = NULL;
164 	struct iso_mnt *imp;
165 	struct iso_extended_attributes *ap = NULL;
166 	int off;
167 
168 	if (!bp
169 	    && ((imp = inop->i_mnt)->im_flags & ISOFSMNT_EXTATT)
170 	    && (off = isonum_711(isodir->ext_attr_length))) {
171 		cd9660_blkatoff(ITOV(inop), (off_t)-(off << imp->im_bshift), NULL,
172 			     &bp2);
173 		bp = bp2;
174 	}
175 	if (bp) {
176 		ap = (struct iso_extended_attributes *)bp->b_data;
177 
178 		if (ftype != ISO_FTYPE_HIGH_SIERRA
179 		    && isonum_711(ap->version) == 1) {
180 			if (!cd9660_tstamp_conv17(ap->ftime,&inop->inode.iso_atime))
181 				cd9660_tstamp_conv17(ap->ctime,&inop->inode.iso_atime);
182 			if (!cd9660_tstamp_conv17(ap->ctime,&inop->inode.iso_ctime))
183 				inop->inode.iso_ctime = inop->inode.iso_atime;
184 			if (!cd9660_tstamp_conv17(ap->mtime,&inop->inode.iso_mtime))
185 				inop->inode.iso_mtime = inop->inode.iso_ctime;
186 		} else
187 			ap = NULL;
188 	}
189 	if (!ap) {
190 		cd9660_tstamp_conv7(isodir->date,&inop->inode.iso_ctime,ftype);
191 		inop->inode.iso_atime = inop->inode.iso_ctime;
192 		inop->inode.iso_mtime = inop->inode.iso_ctime;
193 	}
194 	if (bp2)
195 		brelse(bp2);
196 }
197 
198 int
cd9660_tstamp_conv7(u_char * pi,struct timespec * pu,enum ISO_FTYPE ftype)199 cd9660_tstamp_conv7(u_char *pi, struct timespec *pu, enum ISO_FTYPE ftype)
200 {
201 	int crtime, days;
202 	int y, m, d, hour, minute, second, tz;
203 
204 	y = pi[0] + 1900;
205 	m = pi[1];
206 	d = pi[2];
207 	hour = pi[3];
208 	minute = pi[4];
209 	second = pi[5];
210 	if(ftype != ISO_FTYPE_HIGH_SIERRA)
211 		tz = ((signed char *)pi)[6]; /* Timezone value is signed. */
212 	else
213 		/* original high sierra misses timezone data */
214 		tz = 0;
215 
216 	if (y < 1970) {
217 		pu->tv_sec  = 0;
218 		pu->tv_nsec = 0;
219 		return 0;
220 	} else {
221 #ifdef	ORIGINAL
222 		/* computes day number relative to Sept. 19th,1989 */
223 		/* don't even *THINK* about changing formula. It works! */
224 		days = 367*(y-1980)-7*(y+(m+9)/12)/4-3*((y+(m-9)/7)/100+1)/4+275*m/9+d-100;
225 #else
226 		/*
227 		 * Changed :-) to make it relative to Jan. 1st, 1970
228 		 * and to disambiguate negative division
229 		 */
230 		days = 367*(y-1960)-7*(y+(m+9)/12)/4-3*((y+(m+9)/12-1)/100+1)/4+275*m/9+d-239;
231 #endif
232 		crtime = ((((days * 24) + hour) * 60 + minute) * 60) + second;
233 
234 		/* timezone offset is unreliable on some disks */
235 		if (-48 <= tz && tz <= 52)
236 			crtime -= tz * 15 * 60;
237 	}
238 	pu->tv_sec  = crtime;
239 	pu->tv_nsec = 0;
240 	return 1;
241 }
242 
243 static u_int
cd9660_chars2ui(u_char * begin,int len)244 cd9660_chars2ui(u_char *begin, int len)
245 {
246 	u_int rc;
247 
248 	for (rc = 0; --len >= 0;) {
249 		rc *= 10;
250 		rc += *begin++ - '0';
251 	}
252 	return rc;
253 }
254 
255 int
cd9660_tstamp_conv17(u_char * pi,struct timespec * pu)256 cd9660_tstamp_conv17(u_char *pi, struct timespec *pu)
257 {
258 	u_char buf[7];
259 
260 	/* year:"0001"-"9999" -> -1900  */
261 	buf[0] = cd9660_chars2ui(pi,4) - 1900;
262 
263 	/* month: " 1"-"12"   -> 1 - 12 */
264 	buf[1] = cd9660_chars2ui(pi + 4,2);
265 
266 	/* day:	  " 1"-"31"   -> 1 - 31 */
267 	buf[2] = cd9660_chars2ui(pi + 6,2);
268 
269 	/* hour:  " 0"-"23"   -> 0 - 23 */
270 	buf[3] = cd9660_chars2ui(pi + 8,2);
271 
272 	/* minute:" 0"-"59"   -> 0 - 59 */
273 	buf[4] = cd9660_chars2ui(pi + 10,2);
274 
275 	/* second:" 0"-"59"   -> 0 - 59 */
276 	buf[5] = cd9660_chars2ui(pi + 12,2);
277 
278 	/* difference of GMT */
279 	buf[6] = pi[16];
280 
281 	return cd9660_tstamp_conv7(buf, pu, ISO_FTYPE_DEFAULT);
282 }
283 
284 cd_ino_t
isodirino(struct iso_directory_record * isodir,struct iso_mnt * imp)285 isodirino(struct iso_directory_record *isodir, struct iso_mnt *imp)
286 {
287 	cd_ino_t ino;
288 
289 	/*
290 	 * Note there is an inverse calculation in
291 	 * cd9660_vfsops.c:cd9660_vget_internal():
292 	 *   ip->iso_start = ino >> imp->im_bshift;
293 	 * and also a calculation of the isodir pointer
294 	 * from an inode in cd9660_vnops.c:cd9660_readlink()
295 	 */
296 	ino = ((cd_ino_t)isonum_733(isodir->extent) +
297 		isonum_711(isodir->ext_attr_length)) << imp->im_bshift;
298 	return ino;
299 }
300