309 lines
7.7 KiB
C
309 lines
7.7 KiB
C
/*
|
|
* misc.c
|
|
*
|
|
* PURPOSE
|
|
* Miscellaneous routines for the OSTA-UDF(tm) filesystem.
|
|
*
|
|
* COPYRIGHT
|
|
* This file is distributed under the terms of the GNU General Public
|
|
* License (GPL). Copies of the GPL can be obtained from:
|
|
* ftp://prep.ai.mit.edu/pub/gnu/GPL
|
|
* Each contributing author retains all rights to their own work.
|
|
*
|
|
* (C) 1998 Dave Boynton
|
|
* (C) 1998-2004 Ben Fennema
|
|
* (C) 1999-2000 Stelias Computing Inc
|
|
*
|
|
* HISTORY
|
|
*
|
|
* 04/19/99 blf partial support for reading/writing specific EA's
|
|
*/
|
|
|
|
#include "udfdecl.h"
|
|
|
|
#include <linux/fs.h>
|
|
#include <linux/string.h>
|
|
#include <linux/udf_fs.h>
|
|
#include <linux/buffer_head.h>
|
|
|
|
#include "udf_i.h"
|
|
#include "udf_sb.h"
|
|
|
|
struct buffer_head *
|
|
udf_tgetblk(struct super_block *sb, int block)
|
|
{
|
|
if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV))
|
|
return sb_getblk(sb, udf_fixed_to_variable(block));
|
|
else
|
|
return sb_getblk(sb, block);
|
|
}
|
|
|
|
struct buffer_head *
|
|
udf_tread(struct super_block *sb, int block)
|
|
{
|
|
if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV))
|
|
return sb_bread(sb, udf_fixed_to_variable(block));
|
|
else
|
|
return sb_bread(sb, block);
|
|
}
|
|
|
|
struct genericFormat *
|
|
udf_add_extendedattr(struct inode * inode, uint32_t size, uint32_t type,
|
|
uint8_t loc)
|
|
{
|
|
uint8_t *ea = NULL, *ad = NULL;
|
|
int offset;
|
|
uint16_t crclen;
|
|
int i;
|
|
|
|
ea = UDF_I_DATA(inode);
|
|
if (UDF_I_LENEATTR(inode))
|
|
ad = UDF_I_DATA(inode) + UDF_I_LENEATTR(inode);
|
|
else
|
|
{
|
|
ad = ea;
|
|
size += sizeof(struct extendedAttrHeaderDesc);
|
|
}
|
|
|
|
offset = inode->i_sb->s_blocksize - udf_file_entry_alloc_offset(inode) -
|
|
UDF_I_LENALLOC(inode);
|
|
|
|
/* TODO - Check for FreeEASpace */
|
|
|
|
if (loc & 0x01 && offset >= size)
|
|
{
|
|
struct extendedAttrHeaderDesc *eahd;
|
|
eahd = (struct extendedAttrHeaderDesc *)ea;
|
|
|
|
if (UDF_I_LENALLOC(inode))
|
|
{
|
|
memmove(&ad[size], ad, UDF_I_LENALLOC(inode));
|
|
}
|
|
|
|
if (UDF_I_LENEATTR(inode))
|
|
{
|
|
/* check checksum/crc */
|
|
if (le16_to_cpu(eahd->descTag.tagIdent) != TAG_IDENT_EAHD ||
|
|
le32_to_cpu(eahd->descTag.tagLocation) != UDF_I_LOCATION(inode).logicalBlockNum)
|
|
{
|
|
return NULL;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
size -= sizeof(struct extendedAttrHeaderDesc);
|
|
UDF_I_LENEATTR(inode) += sizeof(struct extendedAttrHeaderDesc);
|
|
eahd->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EAHD);
|
|
if (UDF_SB_UDFREV(inode->i_sb) >= 0x0200)
|
|
eahd->descTag.descVersion = cpu_to_le16(3);
|
|
else
|
|
eahd->descTag.descVersion = cpu_to_le16(2);
|
|
eahd->descTag.tagSerialNum = cpu_to_le16(UDF_SB_SERIALNUM(inode->i_sb));
|
|
eahd->descTag.tagLocation = cpu_to_le32(UDF_I_LOCATION(inode).logicalBlockNum);
|
|
eahd->impAttrLocation = cpu_to_le32(0xFFFFFFFF);
|
|
eahd->appAttrLocation = cpu_to_le32(0xFFFFFFFF);
|
|
}
|
|
|
|
offset = UDF_I_LENEATTR(inode);
|
|
if (type < 2048)
|
|
{
|
|
if (le32_to_cpu(eahd->appAttrLocation) < UDF_I_LENEATTR(inode))
|
|
{
|
|
uint32_t aal = le32_to_cpu(eahd->appAttrLocation);
|
|
memmove(&ea[offset - aal + size],
|
|
&ea[aal], offset - aal);
|
|
offset -= aal;
|
|
eahd->appAttrLocation = cpu_to_le32(aal + size);
|
|
}
|
|
if (le32_to_cpu(eahd->impAttrLocation) < UDF_I_LENEATTR(inode))
|
|
{
|
|
uint32_t ial = le32_to_cpu(eahd->impAttrLocation);
|
|
memmove(&ea[offset - ial + size],
|
|
&ea[ial], offset - ial);
|
|
offset -= ial;
|
|
eahd->impAttrLocation = cpu_to_le32(ial + size);
|
|
}
|
|
}
|
|
else if (type < 65536)
|
|
{
|
|
if (le32_to_cpu(eahd->appAttrLocation) < UDF_I_LENEATTR(inode))
|
|
{
|
|
uint32_t aal = le32_to_cpu(eahd->appAttrLocation);
|
|
memmove(&ea[offset - aal + size],
|
|
&ea[aal], offset - aal);
|
|
offset -= aal;
|
|
eahd->appAttrLocation = cpu_to_le32(aal + size);
|
|
}
|
|
}
|
|
/* rewrite CRC + checksum of eahd */
|
|
crclen = sizeof(struct extendedAttrHeaderDesc) - sizeof(tag);
|
|
eahd->descTag.descCRCLength = cpu_to_le16(crclen);
|
|
eahd->descTag.descCRC = cpu_to_le16(udf_crc((char *)eahd + sizeof(tag), crclen, 0));
|
|
eahd->descTag.tagChecksum = 0;
|
|
for (i=0; i<16; i++)
|
|
if (i != 4)
|
|
eahd->descTag.tagChecksum += ((uint8_t *)&(eahd->descTag))[i];
|
|
UDF_I_LENEATTR(inode) += size;
|
|
return (struct genericFormat *)&ea[offset];
|
|
}
|
|
if (loc & 0x02)
|
|
{
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
struct genericFormat *
|
|
udf_get_extendedattr(struct inode *inode, uint32_t type, uint8_t subtype)
|
|
{
|
|
struct genericFormat *gaf;
|
|
uint8_t *ea = NULL;
|
|
uint32_t offset;
|
|
|
|
ea = UDF_I_DATA(inode);
|
|
|
|
if (UDF_I_LENEATTR(inode))
|
|
{
|
|
struct extendedAttrHeaderDesc *eahd;
|
|
eahd = (struct extendedAttrHeaderDesc *)ea;
|
|
|
|
/* check checksum/crc */
|
|
if (le16_to_cpu(eahd->descTag.tagIdent) != TAG_IDENT_EAHD ||
|
|
le32_to_cpu(eahd->descTag.tagLocation) != UDF_I_LOCATION(inode).logicalBlockNum)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
if (type < 2048)
|
|
offset = sizeof(struct extendedAttrHeaderDesc);
|
|
else if (type < 65536)
|
|
offset = le32_to_cpu(eahd->impAttrLocation);
|
|
else
|
|
offset = le32_to_cpu(eahd->appAttrLocation);
|
|
|
|
while (offset < UDF_I_LENEATTR(inode))
|
|
{
|
|
gaf = (struct genericFormat *)&ea[offset];
|
|
if (le32_to_cpu(gaf->attrType) == type && gaf->attrSubtype == subtype)
|
|
return gaf;
|
|
else
|
|
offset += le32_to_cpu(gaf->attrLength);
|
|
}
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* udf_read_tagged
|
|
*
|
|
* PURPOSE
|
|
* Read the first block of a tagged descriptor.
|
|
*
|
|
* HISTORY
|
|
* July 1, 1997 - Andrew E. Mileski
|
|
* Written, tested, and released.
|
|
*/
|
|
struct buffer_head *
|
|
udf_read_tagged(struct super_block *sb, uint32_t block, uint32_t location, uint16_t *ident)
|
|
{
|
|
tag *tag_p;
|
|
struct buffer_head *bh = NULL;
|
|
register uint8_t checksum;
|
|
register int i;
|
|
|
|
/* Read the block */
|
|
if (block == 0xFFFFFFFF)
|
|
return NULL;
|
|
|
|
bh = udf_tread(sb, block + UDF_SB_SESSION(sb));
|
|
if (!bh)
|
|
{
|
|
udf_debug("block=%d, location=%d: read failed\n", block + UDF_SB_SESSION(sb), location);
|
|
return NULL;
|
|
}
|
|
|
|
tag_p = (tag *)(bh->b_data);
|
|
|
|
*ident = le16_to_cpu(tag_p->tagIdent);
|
|
|
|
if ( location != le32_to_cpu(tag_p->tagLocation) )
|
|
{
|
|
udf_debug("location mismatch block %u, tag %u != %u\n",
|
|
block + UDF_SB_SESSION(sb), le32_to_cpu(tag_p->tagLocation), location);
|
|
goto error_out;
|
|
}
|
|
|
|
/* Verify the tag checksum */
|
|
checksum = 0U;
|
|
for (i = 0; i < 4; i++)
|
|
checksum += (uint8_t)(bh->b_data[i]);
|
|
for (i = 5; i < 16; i++)
|
|
checksum += (uint8_t)(bh->b_data[i]);
|
|
if (checksum != tag_p->tagChecksum) {
|
|
printk(KERN_ERR "udf: tag checksum failed block %d\n", block);
|
|
goto error_out;
|
|
}
|
|
|
|
/* Verify the tag version */
|
|
if (le16_to_cpu(tag_p->descVersion) != 0x0002U &&
|
|
le16_to_cpu(tag_p->descVersion) != 0x0003U)
|
|
{
|
|
udf_debug("tag version 0x%04x != 0x0002 || 0x0003 block %d\n",
|
|
le16_to_cpu(tag_p->descVersion), block);
|
|
goto error_out;
|
|
}
|
|
|
|
/* Verify the descriptor CRC */
|
|
if (le16_to_cpu(tag_p->descCRCLength) + sizeof(tag) > sb->s_blocksize ||
|
|
le16_to_cpu(tag_p->descCRC) == udf_crc(bh->b_data + sizeof(tag),
|
|
le16_to_cpu(tag_p->descCRCLength), 0))
|
|
{
|
|
return bh;
|
|
}
|
|
udf_debug("Crc failure block %d: crc = %d, crclen = %d\n",
|
|
block + UDF_SB_SESSION(sb), le16_to_cpu(tag_p->descCRC), le16_to_cpu(tag_p->descCRCLength));
|
|
|
|
error_out:
|
|
brelse(bh);
|
|
return NULL;
|
|
}
|
|
|
|
struct buffer_head *
|
|
udf_read_ptagged(struct super_block *sb, kernel_lb_addr loc, uint32_t offset, uint16_t *ident)
|
|
{
|
|
return udf_read_tagged(sb, udf_get_lb_pblock(sb, loc, offset),
|
|
loc.logicalBlockNum + offset, ident);
|
|
}
|
|
|
|
void udf_release_data(struct buffer_head *bh)
|
|
{
|
|
if (bh)
|
|
brelse(bh);
|
|
}
|
|
|
|
void udf_update_tag(char *data, int length)
|
|
{
|
|
tag *tptr = (tag *)data;
|
|
int i;
|
|
|
|
length -= sizeof(tag);
|
|
|
|
tptr->tagChecksum = 0;
|
|
tptr->descCRCLength = cpu_to_le16(length);
|
|
tptr->descCRC = cpu_to_le16(udf_crc(data + sizeof(tag), length, 0));
|
|
|
|
for (i=0; i<16; i++)
|
|
if (i != 4)
|
|
tptr->tagChecksum += (uint8_t)(data[i]);
|
|
}
|
|
|
|
void udf_new_tag(char *data, uint16_t ident, uint16_t version, uint16_t snum,
|
|
uint32_t loc, int length)
|
|
{
|
|
tag *tptr = (tag *)data;
|
|
tptr->tagIdent = cpu_to_le16(ident);
|
|
tptr->descVersion = cpu_to_le16(version);
|
|
tptr->tagSerialNum = cpu_to_le16(snum);
|
|
tptr->tagLocation = cpu_to_le32(loc);
|
|
udf_update_tag(data, length);
|
|
}
|