void udf_update_tag(char *data, int length)
{
tag *tptr = (tag *)data;
length -= sizeof(tag);
tptr->descCRCLength = cpu_to_le16(length);
tptr->descCRC = cpu_to_le16(udf_crc(data + sizeof(tag), length, 0));
tptr->tagChecksum = udf_tag_checksum(tptr);
}
int main(void)
{
unsigned short x;
x = udf_crc(bytes, sizeof bytes);
printf("udf_crc: calculated = %4.4x, correct = %4.4x\n", x, 0x3299U);
return 0;
}
/*
* 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;
struct udf_sb_info *sbi = UDF_SB(sb);
/* Read the block */
if (block == 0xFFFFFFFF)
return NULL;
bh = udf_tread(sb, block + sbi->s_session);
if (!bh) {
udf_debug("block=%d, location=%d: read failed\n",
block + sbi->s_session, 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 + sbi->s_session,
le32_to_cpu(tag_p->tagLocation), location);
goto error_out;
}
/* Verify the tag checksum */
if (udf_tag_checksum(tag_p) != tag_p->tagChecksum) {
printk(KERN_ERR "udf: tag checksum failed block %d\n", block);
goto error_out;
}
/* Verify the tag version */
if (tag_p->descVersion != cpu_to_le16(0x0002U) &&
tag_p->descVersion != cpu_to_le16(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 + sbi->s_session, le16_to_cpu(tag_p->descCRC),
le16_to_cpu(tag_p->descCRCLength));
error_out:
brelse(bh);
return NULL;
}
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]);
}
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;
}
/*
* 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 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;
struct udf_inode_info *iinfo = UDF_I(inode);
ea = iinfo->i_ext.i_data;
if (iinfo->i_lenEAttr) {
ad = iinfo->i_ext.i_data + iinfo->i_lenEAttr;
} else {
ad = ea;
size += sizeof(struct extendedAttrHeaderDesc);
}
offset = inode->i_sb->s_blocksize - udf_file_entry_alloc_offset(inode) -
iinfo->i_lenAlloc;
/* TODO - Check for FreeEASpace */
if (loc & 0x01 && offset >= size) {
struct extendedAttrHeaderDesc *eahd;
eahd = (struct extendedAttrHeaderDesc *)ea;
if (iinfo->i_lenAlloc)
memmove(&ad[size], ad, iinfo->i_lenAlloc);
if (iinfo->i_lenEAttr) {
/* check checksum/crc */
if (eahd->descTag.tagIdent !=
cpu_to_le16(TAG_IDENT_EAHD) ||
le32_to_cpu(eahd->descTag.tagLocation) !=
iinfo->i_location.logicalBlockNum)
return NULL;
} else {
struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
size -= sizeof(struct extendedAttrHeaderDesc);
iinfo->i_lenEAttr +=
sizeof(struct extendedAttrHeaderDesc);
eahd->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EAHD);
if (sbi->s_udfrev >= 0x0200)
eahd->descTag.descVersion = cpu_to_le16(3);
else
eahd->descTag.descVersion = cpu_to_le16(2);
eahd->descTag.tagSerialNum =
cpu_to_le16(sbi->s_serial_number);
eahd->descTag.tagLocation = cpu_to_le32(
iinfo->i_location.logicalBlockNum);
eahd->impAttrLocation = cpu_to_le32(0xFFFFFFFF);
eahd->appAttrLocation = cpu_to_le32(0xFFFFFFFF);
}
offset = iinfo->i_lenEAttr;
if (type < 2048) {
if (le32_to_cpu(eahd->appAttrLocation) <
iinfo->i_lenEAttr) {
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) <
iinfo->i_lenEAttr) {
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) <
iinfo->i_lenEAttr) {
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 = udf_tag_checksum(&eahd->descTag);
iinfo->i_lenEAttr += size;
return (struct genericFormat *)&ea[offset];
}
if (loc & 0x02)
;
return NULL;
}
