Linux Audio

Check our new training course

Loading...
v6.2
  1/*
  2 * misc.c
  3 *
  4 * PURPOSE
  5 *	Miscellaneous routines for the OSTA-UDF(tm) filesystem.
  6 *
  7 * COPYRIGHT
  8 *	This file is distributed under the terms of the GNU General Public
  9 *	License (GPL). Copies of the GPL can be obtained from:
 10 *		ftp://prep.ai.mit.edu/pub/gnu/GPL
 11 *	Each contributing author retains all rights to their own work.
 12 *
 13 *  (C) 1998 Dave Boynton
 14 *  (C) 1998-2004 Ben Fennema
 15 *  (C) 1999-2000 Stelias Computing Inc
 16 *
 17 * HISTORY
 18 *
 19 *  04/19/99 blf  partial support for reading/writing specific EA's
 20 */
 21
 22#include "udfdecl.h"
 23
 24#include <linux/fs.h>
 25#include <linux/string.h>
 26#include <linux/crc-itu-t.h>
 27
 28#include "udf_i.h"
 29#include "udf_sb.h"
 30
 31struct buffer_head *udf_tgetblk(struct super_block *sb, udf_pblk_t block)
 32{
 33	if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV))
 34		return sb_getblk(sb, udf_fixed_to_variable(block));
 35	else
 36		return sb_getblk(sb, block);
 37}
 38
 39struct buffer_head *udf_tread(struct super_block *sb, udf_pblk_t block)
 40{
 41	if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV))
 42		return sb_bread(sb, udf_fixed_to_variable(block));
 43	else
 44		return sb_bread(sb, block);
 45}
 46
 47struct genericFormat *udf_add_extendedattr(struct inode *inode, uint32_t size,
 48					   uint32_t type, uint8_t loc)
 49{
 50	uint8_t *ea = NULL, *ad = NULL;
 51	int offset;
 52	uint16_t crclen;
 53	struct udf_inode_info *iinfo = UDF_I(inode);
 54
 55	ea = iinfo->i_data;
 56	if (iinfo->i_lenEAttr) {
 57		ad = iinfo->i_data + iinfo->i_lenEAttr;
 58	} else {
 59		ad = ea;
 60		size += sizeof(struct extendedAttrHeaderDesc);
 61	}
 62
 63	offset = inode->i_sb->s_blocksize - udf_file_entry_alloc_offset(inode) -
 64		iinfo->i_lenAlloc;
 65
 66	/* TODO - Check for FreeEASpace */
 67
 68	if (loc & 0x01 && offset >= size) {
 69		struct extendedAttrHeaderDesc *eahd;
 70		eahd = (struct extendedAttrHeaderDesc *)ea;
 71
 72		if (iinfo->i_lenAlloc)
 73			memmove(&ad[size], ad, iinfo->i_lenAlloc);
 74
 75		if (iinfo->i_lenEAttr) {
 76			/* check checksum/crc */
 77			if (eahd->descTag.tagIdent !=
 78					cpu_to_le16(TAG_IDENT_EAHD) ||
 79			    le32_to_cpu(eahd->descTag.tagLocation) !=
 80					iinfo->i_location.logicalBlockNum)
 81				return NULL;
 82		} else {
 83			struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
 84
 85			size -= sizeof(struct extendedAttrHeaderDesc);
 86			iinfo->i_lenEAttr +=
 87				sizeof(struct extendedAttrHeaderDesc);
 88			eahd->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EAHD);
 89			if (sbi->s_udfrev >= 0x0200)
 90				eahd->descTag.descVersion = cpu_to_le16(3);
 91			else
 92				eahd->descTag.descVersion = cpu_to_le16(2);
 93			eahd->descTag.tagSerialNum =
 94					cpu_to_le16(sbi->s_serial_number);
 95			eahd->descTag.tagLocation = cpu_to_le32(
 96					iinfo->i_location.logicalBlockNum);
 97			eahd->impAttrLocation = cpu_to_le32(0xFFFFFFFF);
 98			eahd->appAttrLocation = cpu_to_le32(0xFFFFFFFF);
 99		}
100
101		offset = iinfo->i_lenEAttr;
102		if (type < 2048) {
103			if (le32_to_cpu(eahd->appAttrLocation) <
104					iinfo->i_lenEAttr) {
105				uint32_t aal =
106					le32_to_cpu(eahd->appAttrLocation);
107				memmove(&ea[offset - aal + size],
108					&ea[aal], offset - aal);
109				offset -= aal;
110				eahd->appAttrLocation =
111						cpu_to_le32(aal + size);
112			}
113			if (le32_to_cpu(eahd->impAttrLocation) <
114					iinfo->i_lenEAttr) {
115				uint32_t ial =
116					le32_to_cpu(eahd->impAttrLocation);
117				memmove(&ea[offset - ial + size],
118					&ea[ial], offset - ial);
119				offset -= ial;
120				eahd->impAttrLocation =
121						cpu_to_le32(ial + size);
122			}
123		} else if (type < 65536) {
124			if (le32_to_cpu(eahd->appAttrLocation) <
125					iinfo->i_lenEAttr) {
126				uint32_t aal =
127					le32_to_cpu(eahd->appAttrLocation);
128				memmove(&ea[offset - aal + size],
129					&ea[aal], offset - aal);
130				offset -= aal;
131				eahd->appAttrLocation =
132						cpu_to_le32(aal + size);
133			}
134		}
135		/* rewrite CRC + checksum of eahd */
136		crclen = sizeof(struct extendedAttrHeaderDesc) - sizeof(struct tag);
137		eahd->descTag.descCRCLength = cpu_to_le16(crclen);
138		eahd->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)eahd +
139						sizeof(struct tag), crclen));
140		eahd->descTag.tagChecksum = udf_tag_checksum(&eahd->descTag);
141		iinfo->i_lenEAttr += size;
142		return (struct genericFormat *)&ea[offset];
143	}
144
145	return NULL;
146}
147
148struct genericFormat *udf_get_extendedattr(struct inode *inode, uint32_t type,
149					   uint8_t subtype)
150{
151	struct genericFormat *gaf;
152	uint8_t *ea = NULL;
153	uint32_t offset;
154	struct udf_inode_info *iinfo = UDF_I(inode);
155
156	ea = iinfo->i_data;
157
158	if (iinfo->i_lenEAttr) {
159		struct extendedAttrHeaderDesc *eahd;
160		eahd = (struct extendedAttrHeaderDesc *)ea;
161
162		/* check checksum/crc */
163		if (eahd->descTag.tagIdent !=
164				cpu_to_le16(TAG_IDENT_EAHD) ||
165		    le32_to_cpu(eahd->descTag.tagLocation) !=
166				iinfo->i_location.logicalBlockNum)
167			return NULL;
168
169		if (type < 2048)
170			offset = sizeof(struct extendedAttrHeaderDesc);
171		else if (type < 65536)
172			offset = le32_to_cpu(eahd->impAttrLocation);
173		else
174			offset = le32_to_cpu(eahd->appAttrLocation);
175
176		while (offset + sizeof(*gaf) < iinfo->i_lenEAttr) {
177			uint32_t attrLength;
178
179			gaf = (struct genericFormat *)&ea[offset];
180			attrLength = le32_to_cpu(gaf->attrLength);
181
182			/* Detect undersized elements and buffer overflows */
183			if ((attrLength < sizeof(*gaf)) ||
184			    (attrLength > (iinfo->i_lenEAttr - offset)))
185				break;
186
187			if (le32_to_cpu(gaf->attrType) == type &&
188					gaf->attrSubtype == subtype)
189				return gaf;
190			else
191				offset += attrLength;
192		}
193	}
194
195	return NULL;
196}
197
198/*
199 * udf_read_tagged
200 *
201 * PURPOSE
202 *	Read the first block of a tagged descriptor.
203 *
204 * HISTORY
205 *	July 1, 1997 - Andrew E. Mileski
206 *	Written, tested, and released.
207 */
208struct buffer_head *udf_read_tagged(struct super_block *sb, uint32_t block,
209				    uint32_t location, uint16_t *ident)
210{
211	struct tag *tag_p;
212	struct buffer_head *bh = NULL;
213	u8 checksum;
214
215	/* Read the block */
216	if (block == 0xFFFFFFFF)
217		return NULL;
218
219	bh = udf_tread(sb, block);
220	if (!bh) {
221		udf_err(sb, "read failed, block=%u, location=%u\n",
222			block, location);
223		return NULL;
224	}
225
226	tag_p = (struct tag *)(bh->b_data);
227
228	*ident = le16_to_cpu(tag_p->tagIdent);
229
230	if (location != le32_to_cpu(tag_p->tagLocation)) {
231		udf_debug("location mismatch block %u, tag %u != %u\n",
232			  block, le32_to_cpu(tag_p->tagLocation), location);
233		goto error_out;
234	}
235
236	/* Verify the tag checksum */
237	checksum = udf_tag_checksum(tag_p);
238	if (checksum != tag_p->tagChecksum) {
239		udf_err(sb, "tag checksum failed, block %u: 0x%02x != 0x%02x\n",
240			block, checksum, tag_p->tagChecksum);
241		goto error_out;
242	}
243
244	/* Verify the tag version */
245	if (tag_p->descVersion != cpu_to_le16(0x0002U) &&
246	    tag_p->descVersion != cpu_to_le16(0x0003U)) {
247		udf_err(sb, "tag version 0x%04x != 0x0002 || 0x0003, block %u\n",
248			le16_to_cpu(tag_p->descVersion), block);
249		goto error_out;
250	}
251
252	/* Verify the descriptor CRC */
253	if (le16_to_cpu(tag_p->descCRCLength) + sizeof(struct tag) > sb->s_blocksize ||
254	    le16_to_cpu(tag_p->descCRC) == crc_itu_t(0,
255					bh->b_data + sizeof(struct tag),
256					le16_to_cpu(tag_p->descCRCLength)))
257		return bh;
258
259	udf_debug("Crc failure block %u: crc = %u, crclen = %u\n", block,
260		  le16_to_cpu(tag_p->descCRC),
261		  le16_to_cpu(tag_p->descCRCLength));
262error_out:
263	brelse(bh);
264	return NULL;
265}
266
267struct buffer_head *udf_read_ptagged(struct super_block *sb,
268				     struct kernel_lb_addr *loc,
269				     uint32_t offset, uint16_t *ident)
270{
271	return udf_read_tagged(sb, udf_get_lb_pblock(sb, loc, offset),
272			       loc->logicalBlockNum + offset, ident);
273}
274
275void udf_update_tag(char *data, int length)
276{
277	struct tag *tptr = (struct tag *)data;
278	length -= sizeof(struct tag);
279
280	tptr->descCRCLength = cpu_to_le16(length);
281	tptr->descCRC = cpu_to_le16(crc_itu_t(0, data + sizeof(struct tag), length));
282	tptr->tagChecksum = udf_tag_checksum(tptr);
283}
284
285void udf_new_tag(char *data, uint16_t ident, uint16_t version, uint16_t snum,
286		 uint32_t loc, int length)
287{
288	struct tag *tptr = (struct tag *)data;
289	tptr->tagIdent = cpu_to_le16(ident);
290	tptr->descVersion = cpu_to_le16(version);
291	tptr->tagSerialNum = cpu_to_le16(snum);
292	tptr->tagLocation = cpu_to_le32(loc);
293	udf_update_tag(data, length);
294}
295
296u8 udf_tag_checksum(const struct tag *t)
297{
298	u8 *data = (u8 *)t;
299	u8 checksum = 0;
300	int i;
301	for (i = 0; i < sizeof(struct tag); ++i)
302		if (i != 4) /* position of checksum */
303			checksum += data[i];
304	return checksum;
305}
v5.14.15
  1/*
  2 * misc.c
  3 *
  4 * PURPOSE
  5 *	Miscellaneous routines for the OSTA-UDF(tm) filesystem.
  6 *
  7 * COPYRIGHT
  8 *	This file is distributed under the terms of the GNU General Public
  9 *	License (GPL). Copies of the GPL can be obtained from:
 10 *		ftp://prep.ai.mit.edu/pub/gnu/GPL
 11 *	Each contributing author retains all rights to their own work.
 12 *
 13 *  (C) 1998 Dave Boynton
 14 *  (C) 1998-2004 Ben Fennema
 15 *  (C) 1999-2000 Stelias Computing Inc
 16 *
 17 * HISTORY
 18 *
 19 *  04/19/99 blf  partial support for reading/writing specific EA's
 20 */
 21
 22#include "udfdecl.h"
 23
 24#include <linux/fs.h>
 25#include <linux/string.h>
 26#include <linux/crc-itu-t.h>
 27
 28#include "udf_i.h"
 29#include "udf_sb.h"
 30
 31struct buffer_head *udf_tgetblk(struct super_block *sb, udf_pblk_t block)
 32{
 33	if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV))
 34		return sb_getblk(sb, udf_fixed_to_variable(block));
 35	else
 36		return sb_getblk(sb, block);
 37}
 38
 39struct buffer_head *udf_tread(struct super_block *sb, udf_pblk_t block)
 40{
 41	if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV))
 42		return sb_bread(sb, udf_fixed_to_variable(block));
 43	else
 44		return sb_bread(sb, block);
 45}
 46
 47struct genericFormat *udf_add_extendedattr(struct inode *inode, uint32_t size,
 48					   uint32_t type, uint8_t loc)
 49{
 50	uint8_t *ea = NULL, *ad = NULL;
 51	int offset;
 52	uint16_t crclen;
 53	struct udf_inode_info *iinfo = UDF_I(inode);
 54
 55	ea = iinfo->i_data;
 56	if (iinfo->i_lenEAttr) {
 57		ad = iinfo->i_data + iinfo->i_lenEAttr;
 58	} else {
 59		ad = ea;
 60		size += sizeof(struct extendedAttrHeaderDesc);
 61	}
 62
 63	offset = inode->i_sb->s_blocksize - udf_file_entry_alloc_offset(inode) -
 64		iinfo->i_lenAlloc;
 65
 66	/* TODO - Check for FreeEASpace */
 67
 68	if (loc & 0x01 && offset >= size) {
 69		struct extendedAttrHeaderDesc *eahd;
 70		eahd = (struct extendedAttrHeaderDesc *)ea;
 71
 72		if (iinfo->i_lenAlloc)
 73			memmove(&ad[size], ad, iinfo->i_lenAlloc);
 74
 75		if (iinfo->i_lenEAttr) {
 76			/* check checksum/crc */
 77			if (eahd->descTag.tagIdent !=
 78					cpu_to_le16(TAG_IDENT_EAHD) ||
 79			    le32_to_cpu(eahd->descTag.tagLocation) !=
 80					iinfo->i_location.logicalBlockNum)
 81				return NULL;
 82		} else {
 83			struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
 84
 85			size -= sizeof(struct extendedAttrHeaderDesc);
 86			iinfo->i_lenEAttr +=
 87				sizeof(struct extendedAttrHeaderDesc);
 88			eahd->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EAHD);
 89			if (sbi->s_udfrev >= 0x0200)
 90				eahd->descTag.descVersion = cpu_to_le16(3);
 91			else
 92				eahd->descTag.descVersion = cpu_to_le16(2);
 93			eahd->descTag.tagSerialNum =
 94					cpu_to_le16(sbi->s_serial_number);
 95			eahd->descTag.tagLocation = cpu_to_le32(
 96					iinfo->i_location.logicalBlockNum);
 97			eahd->impAttrLocation = cpu_to_le32(0xFFFFFFFF);
 98			eahd->appAttrLocation = cpu_to_le32(0xFFFFFFFF);
 99		}
100
101		offset = iinfo->i_lenEAttr;
102		if (type < 2048) {
103			if (le32_to_cpu(eahd->appAttrLocation) <
104					iinfo->i_lenEAttr) {
105				uint32_t aal =
106					le32_to_cpu(eahd->appAttrLocation);
107				memmove(&ea[offset - aal + size],
108					&ea[aal], offset - aal);
109				offset -= aal;
110				eahd->appAttrLocation =
111						cpu_to_le32(aal + size);
112			}
113			if (le32_to_cpu(eahd->impAttrLocation) <
114					iinfo->i_lenEAttr) {
115				uint32_t ial =
116					le32_to_cpu(eahd->impAttrLocation);
117				memmove(&ea[offset - ial + size],
118					&ea[ial], offset - ial);
119				offset -= ial;
120				eahd->impAttrLocation =
121						cpu_to_le32(ial + size);
122			}
123		} else if (type < 65536) {
124			if (le32_to_cpu(eahd->appAttrLocation) <
125					iinfo->i_lenEAttr) {
126				uint32_t aal =
127					le32_to_cpu(eahd->appAttrLocation);
128				memmove(&ea[offset - aal + size],
129					&ea[aal], offset - aal);
130				offset -= aal;
131				eahd->appAttrLocation =
132						cpu_to_le32(aal + size);
133			}
134		}
135		/* rewrite CRC + checksum of eahd */
136		crclen = sizeof(struct extendedAttrHeaderDesc) - sizeof(struct tag);
137		eahd->descTag.descCRCLength = cpu_to_le16(crclen);
138		eahd->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)eahd +
139						sizeof(struct tag), crclen));
140		eahd->descTag.tagChecksum = udf_tag_checksum(&eahd->descTag);
141		iinfo->i_lenEAttr += size;
142		return (struct genericFormat *)&ea[offset];
143	}
144
145	return NULL;
146}
147
148struct genericFormat *udf_get_extendedattr(struct inode *inode, uint32_t type,
149					   uint8_t subtype)
150{
151	struct genericFormat *gaf;
152	uint8_t *ea = NULL;
153	uint32_t offset;
154	struct udf_inode_info *iinfo = UDF_I(inode);
155
156	ea = iinfo->i_data;
157
158	if (iinfo->i_lenEAttr) {
159		struct extendedAttrHeaderDesc *eahd;
160		eahd = (struct extendedAttrHeaderDesc *)ea;
161
162		/* check checksum/crc */
163		if (eahd->descTag.tagIdent !=
164				cpu_to_le16(TAG_IDENT_EAHD) ||
165		    le32_to_cpu(eahd->descTag.tagLocation) !=
166				iinfo->i_location.logicalBlockNum)
167			return NULL;
168
169		if (type < 2048)
170			offset = sizeof(struct extendedAttrHeaderDesc);
171		else if (type < 65536)
172			offset = le32_to_cpu(eahd->impAttrLocation);
173		else
174			offset = le32_to_cpu(eahd->appAttrLocation);
175
176		while (offset + sizeof(*gaf) < iinfo->i_lenEAttr) {
177			uint32_t attrLength;
178
179			gaf = (struct genericFormat *)&ea[offset];
180			attrLength = le32_to_cpu(gaf->attrLength);
181
182			/* Detect undersized elements and buffer overflows */
183			if ((attrLength < sizeof(*gaf)) ||
184			    (attrLength > (iinfo->i_lenEAttr - offset)))
185				break;
186
187			if (le32_to_cpu(gaf->attrType) == type &&
188					gaf->attrSubtype == subtype)
189				return gaf;
190			else
191				offset += attrLength;
192		}
193	}
194
195	return NULL;
196}
197
198/*
199 * udf_read_tagged
200 *
201 * PURPOSE
202 *	Read the first block of a tagged descriptor.
203 *
204 * HISTORY
205 *	July 1, 1997 - Andrew E. Mileski
206 *	Written, tested, and released.
207 */
208struct buffer_head *udf_read_tagged(struct super_block *sb, uint32_t block,
209				    uint32_t location, uint16_t *ident)
210{
211	struct tag *tag_p;
212	struct buffer_head *bh = NULL;
213	u8 checksum;
214
215	/* Read the block */
216	if (block == 0xFFFFFFFF)
217		return NULL;
218
219	bh = udf_tread(sb, block);
220	if (!bh) {
221		udf_err(sb, "read failed, block=%u, location=%u\n",
222			block, location);
223		return NULL;
224	}
225
226	tag_p = (struct tag *)(bh->b_data);
227
228	*ident = le16_to_cpu(tag_p->tagIdent);
229
230	if (location != le32_to_cpu(tag_p->tagLocation)) {
231		udf_debug("location mismatch block %u, tag %u != %u\n",
232			  block, le32_to_cpu(tag_p->tagLocation), location);
233		goto error_out;
234	}
235
236	/* Verify the tag checksum */
237	checksum = udf_tag_checksum(tag_p);
238	if (checksum != tag_p->tagChecksum) {
239		udf_err(sb, "tag checksum failed, block %u: 0x%02x != 0x%02x\n",
240			block, checksum, tag_p->tagChecksum);
241		goto error_out;
242	}
243
244	/* Verify the tag version */
245	if (tag_p->descVersion != cpu_to_le16(0x0002U) &&
246	    tag_p->descVersion != cpu_to_le16(0x0003U)) {
247		udf_err(sb, "tag version 0x%04x != 0x0002 || 0x0003, block %u\n",
248			le16_to_cpu(tag_p->descVersion), block);
249		goto error_out;
250	}
251
252	/* Verify the descriptor CRC */
253	if (le16_to_cpu(tag_p->descCRCLength) + sizeof(struct tag) > sb->s_blocksize ||
254	    le16_to_cpu(tag_p->descCRC) == crc_itu_t(0,
255					bh->b_data + sizeof(struct tag),
256					le16_to_cpu(tag_p->descCRCLength)))
257		return bh;
258
259	udf_debug("Crc failure block %u: crc = %u, crclen = %u\n", block,
260		  le16_to_cpu(tag_p->descCRC),
261		  le16_to_cpu(tag_p->descCRCLength));
262error_out:
263	brelse(bh);
264	return NULL;
265}
266
267struct buffer_head *udf_read_ptagged(struct super_block *sb,
268				     struct kernel_lb_addr *loc,
269				     uint32_t offset, uint16_t *ident)
270{
271	return udf_read_tagged(sb, udf_get_lb_pblock(sb, loc, offset),
272			       loc->logicalBlockNum + offset, ident);
273}
274
275void udf_update_tag(char *data, int length)
276{
277	struct tag *tptr = (struct tag *)data;
278	length -= sizeof(struct tag);
279
280	tptr->descCRCLength = cpu_to_le16(length);
281	tptr->descCRC = cpu_to_le16(crc_itu_t(0, data + sizeof(struct tag), length));
282	tptr->tagChecksum = udf_tag_checksum(tptr);
283}
284
285void udf_new_tag(char *data, uint16_t ident, uint16_t version, uint16_t snum,
286		 uint32_t loc, int length)
287{
288	struct tag *tptr = (struct tag *)data;
289	tptr->tagIdent = cpu_to_le16(ident);
290	tptr->descVersion = cpu_to_le16(version);
291	tptr->tagSerialNum = cpu_to_le16(snum);
292	tptr->tagLocation = cpu_to_le32(loc);
293	udf_update_tag(data, length);
294}
295
296u8 udf_tag_checksum(const struct tag *t)
297{
298	u8 *data = (u8 *)t;
299	u8 checksum = 0;
300	int i;
301	for (i = 0; i < sizeof(struct tag); ++i)
302		if (i != 4) /* position of checksum */
303			checksum += data[i];
304	return checksum;
305}