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Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290// SPDX-License-Identifier: GPL-2.0-only/* * misc.c * * PURPOSE * Miscellaneous routines for the OSTA-UDF(tm) filesystem. * * COPYRIGHT * (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/crc-itu-t.h>
#include "udf_i.h"#include "udf_sb.h"
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_data; if (iinfo->i_lenEAttr) { ad = iinfo->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(struct tag); eahd->descTag.descCRCLength = cpu_to_le16(crclen); eahd->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)eahd + sizeof(struct tag), crclen)); eahd->descTag.tagChecksum = udf_tag_checksum(&eahd->descTag); iinfo->i_lenEAttr += size; return (struct genericFormat *)&ea[offset]; }
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; struct udf_inode_info *iinfo = UDF_I(inode);
ea = iinfo->i_data;
if (iinfo->i_lenEAttr) { struct extendedAttrHeaderDesc *eahd; eahd = (struct extendedAttrHeaderDesc *)ea;
/* 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;
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 + sizeof(*gaf) < iinfo->i_lenEAttr) { uint32_t attrLength;
gaf = (struct genericFormat *)&ea[offset]; attrLength = le32_to_cpu(gaf->attrLength);
/* Detect undersized elements and buffer overflows */ if ((attrLength < sizeof(*gaf)) || (attrLength > (iinfo->i_lenEAttr - offset))) break;
if (le32_to_cpu(gaf->attrType) == type && gaf->attrSubtype == subtype) return gaf; else offset += 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){ struct tag *tag_p; struct buffer_head *bh = NULL; u8 checksum;
/* Read the block */ if (block == 0xFFFFFFFF) return NULL;
bh = sb_bread(sb, block); if (!bh) { udf_err(sb, "read failed, block=%u, location=%u\n", block, location); return NULL; }
tag_p = (struct 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, le32_to_cpu(tag_p->tagLocation), location); goto error_out; }
/* Verify the tag checksum */ checksum = udf_tag_checksum(tag_p); if (checksum != tag_p->tagChecksum) { udf_err(sb, "tag checksum failed, block %u: 0x%02x != 0x%02x\n", block, checksum, tag_p->tagChecksum); goto error_out; }
/* Verify the tag version */ if (tag_p->descVersion != cpu_to_le16(0x0002U) && tag_p->descVersion != cpu_to_le16(0x0003U)) { udf_err(sb, "tag version 0x%04x != 0x0002 || 0x0003, block %u\n", le16_to_cpu(tag_p->descVersion), block); goto error_out; }
/* Verify the descriptor CRC */ if (le16_to_cpu(tag_p->descCRCLength) + sizeof(struct tag) > sb->s_blocksize) { udf_err(sb, "block %u: CRC length %u exceeds block size\n", block, le16_to_cpu(tag_p->descCRCLength)); goto error_out; } if (le16_to_cpu(tag_p->descCRC) == crc_itu_t(0, bh->b_data + sizeof(struct tag), le16_to_cpu(tag_p->descCRCLength))) return bh;
udf_debug("Crc failure block %u: crc = %u, crclen = %u\n", block, 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, struct 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_update_tag(char *data, int length){ struct tag *tptr = (struct tag *)data; length -= sizeof(struct tag);
tptr->descCRCLength = cpu_to_le16(length); tptr->descCRC = cpu_to_le16(crc_itu_t(0, data + sizeof(struct tag), length)); tptr->tagChecksum = udf_tag_checksum(tptr);}
void udf_new_tag(char *data, uint16_t ident, uint16_t version, uint16_t snum, uint32_t loc, int length){ struct tag *tptr = (struct 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);}
u8 udf_tag_checksum(const struct tag *t){ u8 *data = (u8 *)t; u8 checksum = 0; int i; for (i = 0; i < sizeof(struct tag); ++i) if (i != 4) /* position of checksum */ checksum += data[i]; return checksum;}