1 /*
2  *  linux/fs/hpfs/ea.c
3  *
4  *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
5  *
6  *  handling extended attributes
7  */
8 
9 #include "hpfs_fn.h"
10 
11 /* Remove external extended attributes. ano specifies whether a is a
12    direct sector where eas starts or an anode */
13 
hpfs_ea_ext_remove(struct super_block * s,secno a,int ano,unsigned len)14 void hpfs_ea_ext_remove(struct super_block *s, secno a, int ano, unsigned len)
15 {
16 	unsigned pos = 0;
17 	while (pos < len) {
18 		char ex[4 + 255 + 1 + 8];
19 		struct extended_attribute *ea = (struct extended_attribute *)ex;
20 		if (pos + 4 > len) {
21 			hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
22 				ano ? "anode" : "sectors", a, len);
23 			return;
24 		}
25 		if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return;
26 		if (ea->indirect) {
27 			if (ea_valuelen(ea) != 8) {
28 				hpfs_error(s, "ea->indirect set while ea->valuelen!=8, %s %08x, pos %08x",
29 					ano ? "anode" : "sectors", a, pos);
30 				return;
31 			}
32 			if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 9, ex+4))
33 				return;
34 			hpfs_ea_remove(s, ea_sec(ea), ea->anode, ea_len(ea));
35 		}
36 		pos += ea->namelen + ea_valuelen(ea) + 5;
37 	}
38 	if (!ano) hpfs_free_sectors(s, a, (len+511) >> 9);
39 	else {
40 		struct buffer_head *bh;
41 		struct anode *anode;
42 		if ((anode = hpfs_map_anode(s, a, &bh))) {
43 			hpfs_remove_btree(s, &anode->btree);
44 			brelse(bh);
45 			hpfs_free_sectors(s, a, 1);
46 		}
47 	}
48 }
49 
get_indirect_ea(struct super_block * s,int ano,secno a,int size)50 static char *get_indirect_ea(struct super_block *s, int ano, secno a, int size)
51 {
52 	char *ret;
53 	if (!(ret = kmalloc(size + 1, GFP_NOFS))) {
54 		printk("HPFS: out of memory for EA\n");
55 		return NULL;
56 	}
57 	if (hpfs_ea_read(s, a, ano, 0, size, ret)) {
58 		kfree(ret);
59 		return NULL;
60 	}
61 	ret[size] = 0;
62 	return ret;
63 }
64 
set_indirect_ea(struct super_block * s,int ano,secno a,const char * data,int size)65 static void set_indirect_ea(struct super_block *s, int ano, secno a,
66 			    const char *data, int size)
67 {
68 	hpfs_ea_write(s, a, ano, 0, size, data);
69 }
70 
71 /* Read an extended attribute named 'key' into the provided buffer */
72 
hpfs_read_ea(struct super_block * s,struct fnode * fnode,char * key,char * buf,int size)73 int hpfs_read_ea(struct super_block *s, struct fnode *fnode, char *key,
74 		char *buf, int size)
75 {
76 	unsigned pos;
77 	int ano, len;
78 	secno a;
79 	char ex[4 + 255 + 1 + 8];
80 	struct extended_attribute *ea;
81 	struct extended_attribute *ea_end = fnode_end_ea(fnode);
82 	for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
83 		if (!strcmp(ea->name, key)) {
84 			if (ea->indirect)
85 				goto indirect;
86 			if (ea_valuelen(ea) >= size)
87 				return -EINVAL;
88 			memcpy(buf, ea_data(ea), ea_valuelen(ea));
89 			buf[ea_valuelen(ea)] = 0;
90 			return 0;
91 		}
92 	a = le32_to_cpu(fnode->ea_secno);
93 	len = le32_to_cpu(fnode->ea_size_l);
94 	ano = fnode->ea_anode;
95 	pos = 0;
96 	while (pos < len) {
97 		ea = (struct extended_attribute *)ex;
98 		if (pos + 4 > len) {
99 			hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
100 				ano ? "anode" : "sectors", a, len);
101 			return -EIO;
102 		}
103 		if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return -EIO;
104 		if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea->indirect ? 8 : 0), ex + 4))
105 			return -EIO;
106 		if (!strcmp(ea->name, key)) {
107 			if (ea->indirect)
108 				goto indirect;
109 			if (ea_valuelen(ea) >= size)
110 				return -EINVAL;
111 			if (hpfs_ea_read(s, a, ano, pos + 4 + ea->namelen + 1, ea_valuelen(ea), buf))
112 				return -EIO;
113 			buf[ea_valuelen(ea)] = 0;
114 			return 0;
115 		}
116 		pos += ea->namelen + ea_valuelen(ea) + 5;
117 	}
118 	return -ENOENT;
119 indirect:
120 	if (ea_len(ea) >= size)
121 		return -EINVAL;
122 	if (hpfs_ea_read(s, ea_sec(ea), ea->anode, 0, ea_len(ea), buf))
123 		return -EIO;
124 	buf[ea_len(ea)] = 0;
125 	return 0;
126 }
127 
128 /* Read an extended attribute named 'key' */
hpfs_get_ea(struct super_block * s,struct fnode * fnode,char * key,int * size)129 char *hpfs_get_ea(struct super_block *s, struct fnode *fnode, char *key, int *size)
130 {
131 	char *ret;
132 	unsigned pos;
133 	int ano, len;
134 	secno a;
135 	struct extended_attribute *ea;
136 	struct extended_attribute *ea_end = fnode_end_ea(fnode);
137 	for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
138 		if (!strcmp(ea->name, key)) {
139 			if (ea->indirect)
140 				return get_indirect_ea(s, ea->anode, ea_sec(ea), *size = ea_len(ea));
141 			if (!(ret = kmalloc((*size = ea_valuelen(ea)) + 1, GFP_NOFS))) {
142 				printk("HPFS: out of memory for EA\n");
143 				return NULL;
144 			}
145 			memcpy(ret, ea_data(ea), ea_valuelen(ea));
146 			ret[ea_valuelen(ea)] = 0;
147 			return ret;
148 		}
149 	a = le32_to_cpu(fnode->ea_secno);
150 	len = le32_to_cpu(fnode->ea_size_l);
151 	ano = fnode->ea_anode;
152 	pos = 0;
153 	while (pos < len) {
154 		char ex[4 + 255 + 1 + 8];
155 		ea = (struct extended_attribute *)ex;
156 		if (pos + 4 > len) {
157 			hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
158 				ano ? "anode" : "sectors", a, len);
159 			return NULL;
160 		}
161 		if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return NULL;
162 		if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea->indirect ? 8 : 0), ex + 4))
163 			return NULL;
164 		if (!strcmp(ea->name, key)) {
165 			if (ea->indirect)
166 				return get_indirect_ea(s, ea->anode, ea_sec(ea), *size = ea_len(ea));
167 			if (!(ret = kmalloc((*size = ea_valuelen(ea)) + 1, GFP_NOFS))) {
168 				printk("HPFS: out of memory for EA\n");
169 				return NULL;
170 			}
171 			if (hpfs_ea_read(s, a, ano, pos + 4 + ea->namelen + 1, ea_valuelen(ea), ret)) {
172 				kfree(ret);
173 				return NULL;
174 			}
175 			ret[ea_valuelen(ea)] = 0;
176 			return ret;
177 		}
178 		pos += ea->namelen + ea_valuelen(ea) + 5;
179 	}
180 	return NULL;
181 }
182 
183 /*
184  * Update or create extended attribute 'key' with value 'data'. Note that
185  * when this ea exists, it MUST have the same size as size of data.
186  * This driver can't change sizes of eas ('cause I just don't need it).
187  */
188 
hpfs_set_ea(struct inode * inode,struct fnode * fnode,const char * key,const char * data,int size)189 void hpfs_set_ea(struct inode *inode, struct fnode *fnode, const char *key,
190 		 const char *data, int size)
191 {
192 	fnode_secno fno = inode->i_ino;
193 	struct super_block *s = inode->i_sb;
194 	unsigned pos;
195 	int ano, len;
196 	secno a;
197 	unsigned char h[4];
198 	struct extended_attribute *ea;
199 	struct extended_attribute *ea_end = fnode_end_ea(fnode);
200 	for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
201 		if (!strcmp(ea->name, key)) {
202 			if (ea->indirect) {
203 				if (ea_len(ea) == size)
204 					set_indirect_ea(s, ea->anode, ea_sec(ea), data, size);
205 			} else if (ea_valuelen(ea) == size) {
206 				memcpy(ea_data(ea), data, size);
207 			}
208 			return;
209 		}
210 	a = le32_to_cpu(fnode->ea_secno);
211 	len = le32_to_cpu(fnode->ea_size_l);
212 	ano = fnode->ea_anode;
213 	pos = 0;
214 	while (pos < len) {
215 		char ex[4 + 255 + 1 + 8];
216 		ea = (struct extended_attribute *)ex;
217 		if (pos + 4 > len) {
218 			hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
219 				ano ? "anode" : "sectors", a, len);
220 			return;
221 		}
222 		if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return;
223 		if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea->indirect ? 8 : 0), ex + 4))
224 			return;
225 		if (!strcmp(ea->name, key)) {
226 			if (ea->indirect) {
227 				if (ea_len(ea) == size)
228 					set_indirect_ea(s, ea->anode, ea_sec(ea), data, size);
229 			}
230 			else {
231 				if (ea_valuelen(ea) == size)
232 					hpfs_ea_write(s, a, ano, pos + 4 + ea->namelen + 1, size, data);
233 			}
234 			return;
235 		}
236 		pos += ea->namelen + ea_valuelen(ea) + 5;
237 	}
238 	if (!le16_to_cpu(fnode->ea_offs)) {
239 		/*if (le16_to_cpu(fnode->ea_size_s)) {
240 			hpfs_error(s, "fnode %08x: ea_size_s == %03x, ea_offs == 0",
241 				inode->i_ino, le16_to_cpu(fnode->ea_size_s));
242 			return;
243 		}*/
244 		fnode->ea_offs = cpu_to_le16(0xc4);
245 	}
246 	if (le16_to_cpu(fnode->ea_offs) < 0xc4 || le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s) > 0x200) {
247 		hpfs_error(s, "fnode %08lx: ea_offs == %03x, ea_size_s == %03x",
248 			(unsigned long)inode->i_ino,
249 			le32_to_cpu(fnode->ea_offs), le16_to_cpu(fnode->ea_size_s));
250 		return;
251 	}
252 	if ((le16_to_cpu(fnode->ea_size_s) || !le32_to_cpu(fnode->ea_size_l)) &&
253 	     le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s) + strlen(key) + size + 5 <= 0x200) {
254 		ea = fnode_end_ea(fnode);
255 		*(char *)ea = 0;
256 		ea->namelen = strlen(key);
257 		ea->valuelen_lo = size;
258 		ea->valuelen_hi = size >> 8;
259 		strcpy(ea->name, key);
260 		memcpy(ea_data(ea), data, size);
261 		fnode->ea_size_s = cpu_to_le16(le16_to_cpu(fnode->ea_size_s) + strlen(key) + size + 5);
262 		goto ret;
263 	}
264 	/* Most the code here is 99.9993422% unused. I hope there are no bugs.
265 	   But what .. HPFS.IFS has also bugs in ea management. */
266 	if (le16_to_cpu(fnode->ea_size_s) && !le32_to_cpu(fnode->ea_size_l)) {
267 		secno n;
268 		struct buffer_head *bh;
269 		char *data;
270 		if (!(n = hpfs_alloc_sector(s, fno, 1, 0))) return;
271 		if (!(data = hpfs_get_sector(s, n, &bh))) {
272 			hpfs_free_sectors(s, n, 1);
273 			return;
274 		}
275 		memcpy(data, fnode_ea(fnode), le16_to_cpu(fnode->ea_size_s));
276 		fnode->ea_size_l = cpu_to_le32(le16_to_cpu(fnode->ea_size_s));
277 		fnode->ea_size_s = cpu_to_le16(0);
278 		fnode->ea_secno = cpu_to_le32(n);
279 		fnode->ea_anode = cpu_to_le32(0);
280 		mark_buffer_dirty(bh);
281 		brelse(bh);
282 	}
283 	pos = le32_to_cpu(fnode->ea_size_l) + 5 + strlen(key) + size;
284 	len = (le32_to_cpu(fnode->ea_size_l) + 511) >> 9;
285 	if (pos >= 30000) goto bail;
286 	while (((pos + 511) >> 9) > len) {
287 		if (!len) {
288 			secno q = hpfs_alloc_sector(s, fno, 1, 0);
289 			if (!q) goto bail;
290 			fnode->ea_secno = cpu_to_le32(q);
291 			fnode->ea_anode = 0;
292 			len++;
293 		} else if (!fnode->ea_anode) {
294 			if (hpfs_alloc_if_possible(s, le32_to_cpu(fnode->ea_secno) + len)) {
295 				len++;
296 			} else {
297 				/* Aargh... don't know how to create ea anodes :-( */
298 				/*struct buffer_head *bh;
299 				struct anode *anode;
300 				anode_secno a_s;
301 				if (!(anode = hpfs_alloc_anode(s, fno, &a_s, &bh)))
302 					goto bail;
303 				anode->up = cpu_to_le32(fno);
304 				anode->btree.fnode_parent = 1;
305 				anode->btree.n_free_nodes--;
306 				anode->btree.n_used_nodes++;
307 				anode->btree.first_free = cpu_to_le16(le16_to_cpu(anode->btree.first_free) + 12);
308 				anode->u.external[0].disk_secno = cpu_to_le32(le32_to_cpu(fnode->ea_secno));
309 				anode->u.external[0].file_secno = cpu_to_le32(0);
310 				anode->u.external[0].length = cpu_to_le32(len);
311 				mark_buffer_dirty(bh);
312 				brelse(bh);
313 				fnode->ea_anode = 1;
314 				fnode->ea_secno = cpu_to_le32(a_s);*/
315 				secno new_sec;
316 				int i;
317 				if (!(new_sec = hpfs_alloc_sector(s, fno, 1, 1 - ((pos + 511) >> 9))))
318 					goto bail;
319 				for (i = 0; i < len; i++) {
320 					struct buffer_head *bh1, *bh2;
321 					void *b1, *b2;
322 					if (!(b1 = hpfs_map_sector(s, le32_to_cpu(fnode->ea_secno) + i, &bh1, len - i - 1))) {
323 						hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
324 						goto bail;
325 					}
326 					if (!(b2 = hpfs_get_sector(s, new_sec + i, &bh2))) {
327 						brelse(bh1);
328 						hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
329 						goto bail;
330 					}
331 					memcpy(b2, b1, 512);
332 					brelse(bh1);
333 					mark_buffer_dirty(bh2);
334 					brelse(bh2);
335 				}
336 				hpfs_free_sectors(s, le32_to_cpu(fnode->ea_secno), len);
337 				fnode->ea_secno = cpu_to_le32(new_sec);
338 				len = (pos + 511) >> 9;
339 			}
340 		}
341 		if (fnode->ea_anode) {
342 			if (hpfs_add_sector_to_btree(s, le32_to_cpu(fnode->ea_secno),
343 						     0, len) != -1) {
344 				len++;
345 			} else {
346 				goto bail;
347 			}
348 		}
349 	}
350 	h[0] = 0;
351 	h[1] = strlen(key);
352 	h[2] = size & 0xff;
353 	h[3] = size >> 8;
354 	if (hpfs_ea_write(s, le32_to_cpu(fnode->ea_secno), fnode->ea_anode, le32_to_cpu(fnode->ea_size_l), 4, h)) goto bail;
355 	if (hpfs_ea_write(s, le32_to_cpu(fnode->ea_secno), fnode->ea_anode, le32_to_cpu(fnode->ea_size_l) + 4, h[1] + 1, key)) goto bail;
356 	if (hpfs_ea_write(s, le32_to_cpu(fnode->ea_secno), fnode->ea_anode, le32_to_cpu(fnode->ea_size_l) + 5 + h[1], size, data)) goto bail;
357 	fnode->ea_size_l = cpu_to_le32(pos);
358 	ret:
359 	hpfs_i(inode)->i_ea_size += 5 + strlen(key) + size;
360 	return;
361 	bail:
362 	if (le32_to_cpu(fnode->ea_secno))
363 		if (fnode->ea_anode) hpfs_truncate_btree(s, le32_to_cpu(fnode->ea_secno), 1, (le32_to_cpu(fnode->ea_size_l) + 511) >> 9);
364 		else hpfs_free_sectors(s, le32_to_cpu(fnode->ea_secno) + ((le32_to_cpu(fnode->ea_size_l) + 511) >> 9), len - ((le32_to_cpu(fnode->ea_size_l) + 511) >> 9));
365 	else fnode->ea_secno = fnode->ea_size_l = cpu_to_le32(0);
366 }
367 
368