Home Home > GIT Browse
summaryrefslogtreecommitdiff
blob: a790821366a7f045d068fe47df517dc479b0ecce (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
/*
 *  linux/fs/hpfs/map.c
 *
 *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
 *
 *  mapping structures to memory with some minimal checks
 */

#include "hpfs_fn.h"

unsigned *hpfs_map_dnode_bitmap(struct super_block *s, struct quad_buffer_head *qbh)
{
	return hpfs_map_4sectors(s, hpfs_sb(s)->sb_dmap, qbh, 0);
}

unsigned int *hpfs_map_bitmap(struct super_block *s, unsigned bmp_block,
			 struct quad_buffer_head *qbh, char *id)
{
	secno sec;
	if (hpfs_sb(s)->sb_chk) if (bmp_block * 16384 > hpfs_sb(s)->sb_fs_size) {
		hpfs_error(s, "hpfs_map_bitmap called with bad parameter: %08x at %s", bmp_block, id);
		return NULL;
	}
	sec = le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[bmp_block]);
	if (!sec || sec > hpfs_sb(s)->sb_fs_size-4) {
		hpfs_error(s, "invalid bitmap block pointer %08x -> %08x at %s", bmp_block, sec, id);
		return NULL;
	}
	return hpfs_map_4sectors(s, sec, qbh, 4);
}

/*
 * Load first code page into kernel memory, return pointer to 256-byte array,
 * first 128 bytes are uppercasing table for chars 128-255, next 128 bytes are
 * lowercasing table
 */

unsigned char *hpfs_load_code_page(struct super_block *s, secno cps)
{
	struct buffer_head *bh;
	secno cpds;
	unsigned cpi;
	unsigned char *ptr;
	unsigned char *cp_table;
	int i;
	struct code_page_data *cpd;
	struct code_page_directory *cp = hpfs_map_sector(s, cps, &bh, 0);
	if (!cp) return NULL;
	if (le32_to_cpu(cp->magic) != CP_DIR_MAGIC) {
		printk("HPFS: Code page directory magic doesn't match (magic = %08x)\n", le32_to_cpu(cp->magic));
		brelse(bh);
		return NULL;
	}
	if (!le32_to_cpu(cp->n_code_pages)) {
		printk("HPFS: n_code_pages == 0\n");
		brelse(bh);
		return NULL;
	}
	cpds = le32_to_cpu(cp->array[0].code_page_data);
	cpi = le16_to_cpu(cp->array[0].index);
	brelse(bh);

	if (cpi >= 3) {
		printk("HPFS: Code page index out of array\n");
		return NULL;
	}
	
	if (!(cpd = hpfs_map_sector(s, cpds, &bh, 0))) return NULL;
	if (le16_to_cpu(cpd->offs[cpi]) > 0x178) {
		printk("HPFS: Code page index out of sector\n");
		brelse(bh);
		return NULL;
	}
	ptr = (unsigned char *)cpd + le16_to_cpu(cpd->offs[cpi]) + 6;
	if (!(cp_table = kmalloc(256, GFP_KERNEL))) {
		printk("HPFS: out of memory for code page table\n");
		brelse(bh);
		return NULL;
	}
	memcpy(cp_table, ptr, 128);
	brelse(bh);

	/* Try to build lowercasing table from uppercasing one */

	for (i=128; i<256; i++) cp_table[i]=i;
	for (i=128; i<256; i++) if (cp_table[i-128]!=i && cp_table[i-128]>=128)
		cp_table[cp_table[i-128]] = i;
	
	return cp_table;
}

secno *hpfs_load_bitmap_directory(struct super_block *s, secno bmp)
{
	struct buffer_head *bh;
	int n = (hpfs_sb(s)->sb_fs_size + 0x200000 - 1) >> 21;
	int i;
	secno *b;
	if (!(b = kmalloc(n * 512, GFP_KERNEL))) {
		printk("HPFS: can't allocate memory for bitmap directory\n");
		return NULL;
	}	
	for (i=0;i<n;i++) {
		secno *d = hpfs_map_sector(s, bmp+i, &bh, n - i - 1);
		if (!d) {
			kfree(b);
			return NULL;
		}
		memcpy((char *)b + 512 * i, d, 512);
		brelse(bh);
	}
	return b;
}

/*
 * Load fnode to memory
 */

struct fnode *hpfs_map_fnode(struct super_block *s, ino_t ino, struct buffer_head **bhp)
{
	struct fnode *fnode;
	if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, ino, 1, "fnode")) {
		return NULL;
	}
	if ((fnode = hpfs_map_sector(s, ino, bhp, FNODE_RD_AHEAD))) {
		if (hpfs_sb(s)->sb_chk) {
			struct extended_attribute *ea;
			struct extended_attribute *ea_end;
			if (le32_to_cpu(fnode->magic) != FNODE_MAGIC) {
				hpfs_error(s, "bad magic on fnode %08lx",
					(unsigned long)ino);
				goto bail;
			}
			if (!fnode->dirflag) {
				if ((unsigned)fnode->btree.n_used_nodes + (unsigned)fnode->btree.n_free_nodes !=
				    (fnode->btree.internal ? 12 : 8)) {
					hpfs_error(s,
					   "bad number of nodes in fnode %08lx",
					    (unsigned long)ino);
					goto bail;
				}
				if (le16_to_cpu(fnode->btree.first_free) !=
				    8 + fnode->btree.n_used_nodes * (fnode->btree.internal ? 8 : 12)) {
					hpfs_error(s,
					    "bad first_free pointer in fnode %08lx",
					    (unsigned long)ino);
					goto bail;
				}
			}
			if (le16_to_cpu(fnode->ea_size_s) && (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)) {
				hpfs_error(s,
					"bad EA info in fnode %08lx: ea_offs == %04x ea_size_s == %04x",
					(unsigned long)ino,
					le16_to_cpu(fnode->ea_offs), le16_to_cpu(fnode->ea_size_s));
				goto bail;
			}
			ea = fnode_ea(fnode);
			ea_end = fnode_end_ea(fnode);
			while (ea != ea_end) {
				if (ea > ea_end) {
					hpfs_error(s, "bad EA in fnode %08lx",
						(unsigned long)ino);
					goto bail;
				}
				ea = next_ea(ea);
			}
		}
	}
	return fnode;
	bail:
	brelse(*bhp);
	return NULL;
}

struct anode *hpfs_map_anode(struct super_block *s, anode_secno ano, struct buffer_head **bhp)
{
	struct anode *anode;
	if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, ano, 1, "anode")) return NULL;
	if ((anode = hpfs_map_sector(s, ano, bhp, ANODE_RD_AHEAD)))
		if (hpfs_sb(s)->sb_chk) {
			if (le32_to_cpu(anode->magic) != ANODE_MAGIC) {
				hpfs_error(s, "bad magic on anode %08x", ano);
				goto bail;
			}
			if (le32_to_cpu(anode->self) != ano) {
				hpfs_error(s, "self pointer invalid on anode %08x", ano);
				goto bail;
			}
			if ((unsigned)anode->btree.n_used_nodes + (unsigned)anode->btree.n_free_nodes !=
			    (anode->btree.internal ? 60 : 40)) {
				hpfs_error(s, "bad number of nodes in anode %08x", ano);
				goto bail;
			}
			if (le16_to_cpu(anode->btree.first_free) !=
			    8 + anode->btree.n_used_nodes * (anode->btree.internal ? 8 : 12)) {
				hpfs_error(s, "bad first_free pointer in anode %08x", ano);
				goto bail;
			}
		}
	return anode;
	bail:
	brelse(*bhp);
	return NULL;
}

/*
 * Load dnode to memory and do some checks
 */

struct dnode *hpfs_map_dnode(struct super_block *s, unsigned secno,
			     struct quad_buffer_head *qbh)
{
	struct dnode *dnode;
	if (hpfs_sb(s)->sb_chk) {
		if (hpfs_chk_sectors(s, secno, 4, "dnode")) return NULL;
		if (secno & 3) {
			hpfs_error(s, "dnode %08x not byte-aligned", secno);
			return NULL;
		}	
	}
	if ((dnode = hpfs_map_4sectors(s, secno, qbh, DNODE_RD_AHEAD)))
		if (hpfs_sb(s)->sb_chk) {
			unsigned p, pp = 0;
			unsigned char *d = (unsigned char *)dnode;
			int b = 0;
			if (le32_to_cpu(dnode->magic) != DNODE_MAGIC) {
				hpfs_error(s, "bad magic on dnode %08x", secno);
				goto bail;
			}
			if (le32_to_cpu(dnode->self) != secno)
				hpfs_error(s, "bad self pointer on dnode %08x self = %08x", secno, le32_to_cpu(dnode->self));
			/* Check dirents - bad dirents would cause infinite
			   loops or shooting to memory */
			if (le32_to_cpu(dnode->first_free) > 2048) {
				hpfs_error(s, "dnode %08x has first_free == %08x", secno, le32_to_cpu(dnode->first_free));
				goto bail;
			}
			for (p = 20; p < le32_to_cpu(dnode->first_free); p += d[p] + (d[p+1] << 8)) {
				struct hpfs_dirent *de = (struct hpfs_dirent *)((char *)dnode + p);
				if (le16_to_cpu(de->length) > 292 || (le16_to_cpu(de->length) < 32) || (le16_to_cpu(de->length) & 3) || p + le16_to_cpu(de->length) > 2048) {
					hpfs_error(s, "bad dirent size in dnode %08x, dirent %03x, last %03x", secno, p, pp);
					goto bail;
				}
				if (((31 + de->namelen + de->down*4 + 3) & ~3) != le16_to_cpu(de->length)) {
					if (((31 + de->namelen + de->down*4 + 3) & ~3) < le16_to_cpu(de->length) && s->s_flags & MS_RDONLY) goto ok;
					hpfs_error(s, "namelen does not match dirent size in dnode %08x, dirent %03x, last %03x", secno, p, pp);
					goto bail;
				}
				ok:
				if (hpfs_sb(s)->sb_chk >= 2) b |= 1 << de->down;
				if (de->down) if (de_down_pointer(de) < 0x10) {
					hpfs_error(s, "bad down pointer in dnode %08x, dirent %03x, last %03x", secno, p, pp);
					goto bail;
				}
				pp = p;
				
			}
			if (p != le32_to_cpu(dnode->first_free)) {
				hpfs_error(s, "size on last dirent does not match first_free; dnode %08x", secno);
				goto bail;
			}
			if (d[pp + 30] != 1 || d[pp + 31] != 255) {
				hpfs_error(s, "dnode %08x does not end with \\377 entry", secno);
				goto bail;
			}
			if (b == 3) printk("HPFS: warning: unbalanced dnode tree, dnode %08x; see hpfs.txt 4 more info\n", secno);
		}
	return dnode;
	bail:
	hpfs_brelse4(qbh);
	return NULL;
}

dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino)
{
	struct buffer_head *bh;
	struct fnode *fnode;
	dnode_secno dno;

	fnode = hpfs_map_fnode(s, ino, &bh);
	if (!fnode)
		return 0;

	dno = le32_to_cpu(fnode->u.external[0].disk_secno);
	brelse(bh);
	return dno;
}