/*
* ext_attr.c --- extended attribute blocks
- *
+ *
* Copyright (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
*
* Copyright (C) 2002 Theodore Ts'o.
*
* %Begin-Header%
- * This file may be redistributed under the terms of the GNU Public
- * License.
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
* %End-Header%
*/
+#include "config.h"
#include <stdio.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#include "ext2fs.h"
-errcode_t ext2fs_read_ext_attr(ext2_filsys fs, blk_t block, void *buf)
+#define NAME_HASH_SHIFT 5
+#define VALUE_HASH_SHIFT 16
+
+/*
+ * ext2_xattr_hash_entry()
+ *
+ * Compute the hash of an extended attribute.
+ */
+__u32 ext2fs_ext_attr_hash_entry(struct ext2_ext_attr_entry *entry, void *data)
+{
+ __u32 hash = 0;
+ char *name = ((char *) entry) + sizeof(struct ext2_ext_attr_entry);
+ int n;
+
+ for (n = 0; n < entry->e_name_len; n++) {
+ hash = (hash << NAME_HASH_SHIFT) ^
+ (hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^
+ *name++;
+ }
+
+ /* The hash needs to be calculated on the data in little-endian. */
+ if (entry->e_value_block == 0 && entry->e_value_size != 0) {
+ __u32 *value = (__u32 *)data;
+ for (n = (entry->e_value_size + EXT2_EXT_ATTR_ROUND) >>
+ EXT2_EXT_ATTR_PAD_BITS; n; n--) {
+ hash = (hash << VALUE_HASH_SHIFT) ^
+ (hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^
+ ext2fs_le32_to_cpu(*value++);
+ }
+ }
+
+ return hash;
+}
+
+static errcode_t check_ext_attr_header(struct ext2_ext_attr_header *header)
{
+ if ((header->h_magic != EXT2_EXT_ATTR_MAGIC_v1 &&
+ header->h_magic != EXT2_EXT_ATTR_MAGIC) ||
+ header->h_blocks != 1)
+ return EXT2_ET_BAD_EA_HEADER;
+
+ return 0;
+}
+
+#undef NAME_HASH_SHIFT
+#undef VALUE_HASH_SHIFT
+
+errcode_t ext2fs_read_ext_attr3(ext2_filsys fs, blk64_t block, void *buf,
+ ext2_ino_t inum)
+{
+ int csum_failed = 0;
errcode_t retval;
- retval = io_channel_read_blk(fs->io, block, 1, buf);
+ retval = io_channel_read_blk64(fs->io, block, 1, buf);
if (retval)
return retval;
+
+ if (!(fs->flags & EXT2_FLAG_IGNORE_CSUM_ERRORS) &&
+ !ext2fs_ext_attr_block_csum_verify(fs, inum, block, buf))
+ csum_failed = 1;
+
#ifdef WORDS_BIGENDIAN
ext2fs_swap_ext_attr(buf, buf, fs->blocksize, 1);
#endif
- return 0;
+
+ retval = check_ext_attr_header(buf);
+ if (retval == 0 && csum_failed)
+ retval = EXT2_ET_EXT_ATTR_CSUM_INVALID;
+
+ return retval;
}
-errcode_t ext2fs_write_ext_attr(ext2_filsys fs, blk_t block, void *inbuf)
+errcode_t ext2fs_read_ext_attr2(ext2_filsys fs, blk64_t block, void *buf)
+{
+ return ext2fs_read_ext_attr3(fs, block, buf, 0);
+}
+
+errcode_t ext2fs_read_ext_attr(ext2_filsys fs, blk_t block, void *buf)
+{
+ return ext2fs_read_ext_attr2(fs, block, buf);
+}
+
+errcode_t ext2fs_write_ext_attr3(ext2_filsys fs, blk64_t block, void *inbuf,
+ ext2_ino_t inum)
{
errcode_t retval;
char *write_buf;
- char *buf = NULL;
#ifdef WORDS_BIGENDIAN
- retval = ext2fs_get_mem(fs->blocksize, &buf);
+ retval = ext2fs_get_mem(fs->blocksize, &write_buf);
if (retval)
return retval;
- write_buf = buf;
- ext2fs_swap_ext_attr(buf, inbuf, fs->blocksize, 1);
+ ext2fs_swap_ext_attr(write_buf, inbuf, fs->blocksize, 1);
#else
write_buf = (char *) inbuf;
#endif
- retval = io_channel_write_blk(fs->io, block, 1, write_buf);
- if (buf)
- ext2fs_free_mem(&buf);
+
+ retval = ext2fs_ext_attr_block_csum_set(fs, inum, block,
+ (struct ext2_ext_attr_header *)write_buf);
+ if (retval)
+ return retval;
+
+ retval = io_channel_write_blk64(fs->io, block, 1, write_buf);
+#ifdef WORDS_BIGENDIAN
+ ext2fs_free_mem(&write_buf);
+#endif
if (!retval)
ext2fs_mark_changed(fs);
return retval;
}
+errcode_t ext2fs_write_ext_attr2(ext2_filsys fs, blk64_t block, void *inbuf)
+{
+ return ext2fs_write_ext_attr3(fs, block, inbuf, 0);
+}
+
+errcode_t ext2fs_write_ext_attr(ext2_filsys fs, blk_t block, void *inbuf)
+{
+ return ext2fs_write_ext_attr2(fs, block, inbuf);
+}
+
/*
* This function adjusts the reference count of the EA block.
*/
-errcode_t ext2fs_adjust_ea_refcount(ext2_filsys fs, blk_t blk,
+errcode_t ext2fs_adjust_ea_refcount3(ext2_filsys fs, blk64_t blk,
char *block_buf, int adjust,
- __u32 *newcount)
+ __u32 *newcount, ext2_ino_t inum)
{
errcode_t retval;
struct ext2_ext_attr_header *header;
char *buf = 0;
- if ((blk >= fs->super->s_blocks_count) ||
+ if ((blk >= ext2fs_blocks_count(fs->super)) ||
(blk < fs->super->s_first_data_block))
return EXT2_ET_BAD_EA_BLOCK_NUM;
block_buf = buf;
}
- retval = ext2fs_read_ext_attr(fs, blk, block_buf);
+ retval = ext2fs_read_ext_attr3(fs, blk, block_buf, inum);
if (retval)
goto errout;
if (newcount)
*newcount = header->h_refcount;
- retval = ext2fs_write_ext_attr(fs, blk, block_buf);
+ retval = ext2fs_write_ext_attr3(fs, blk, block_buf, inum);
if (retval)
goto errout;
ext2fs_free_mem(&buf);
return retval;
}
+
+errcode_t ext2fs_adjust_ea_refcount2(ext2_filsys fs, blk64_t blk,
+ char *block_buf, int adjust,
+ __u32 *newcount)
+{
+ return ext2fs_adjust_ea_refcount3(fs, blk, block_buf, adjust,
+ newcount, 0);
+}
+
+errcode_t ext2fs_adjust_ea_refcount(ext2_filsys fs, blk_t blk,
+ char *block_buf, int adjust,
+ __u32 *newcount)
+{
+ return ext2fs_adjust_ea_refcount2(fs, blk, block_buf, adjust,
+ newcount);
+}
+
+/* Manipulate the contents of extended attribute regions */
+struct ext2_xattr {
+ char *name;
+ void *value;
+ size_t value_len;
+};
+
+struct ext2_xattr_handle {
+ errcode_t magic;
+ ext2_filsys fs;
+ struct ext2_xattr *attrs;
+ size_t length, count;
+ ext2_ino_t ino;
+ int dirty;
+};
+
+static errcode_t ext2fs_xattrs_expand(struct ext2_xattr_handle *h,
+ unsigned int expandby)
+{
+ struct ext2_xattr *new_attrs;
+ errcode_t err;
+
+ err = ext2fs_get_arrayzero(h->length + expandby,
+ sizeof(struct ext2_xattr), &new_attrs);
+ if (err)
+ return err;
+
+ memcpy(new_attrs, h->attrs, h->length * sizeof(struct ext2_xattr));
+ ext2fs_free_mem(&h->attrs);
+ h->length += expandby;
+ h->attrs = new_attrs;
+
+ return 0;
+}
+
+struct ea_name_index {
+ int index;
+ const char *name;
+};
+
+/* Keep these names sorted in order of decreasing specificity. */
+static struct ea_name_index ea_names[] = {
+ {3, "system.posix_acl_default"},
+ {2, "system.posix_acl_access"},
+ {8, "system.richacl"},
+ {6, "security."},
+ {4, "trusted."},
+ {7, "system."},
+ {1, "user."},
+ {0, NULL},
+};
+
+static void move_inline_data_to_front(struct ext2_xattr_handle *h)
+{
+ struct ext2_xattr *x;
+ struct ext2_xattr tmp;
+
+ for (x = h->attrs + 1; x < h->attrs + h->length; x++) {
+ if (!x->name)
+ continue;
+
+ if (strcmp(x->name, "system.data") == 0) {
+ memcpy(&tmp, x, sizeof(tmp));
+ memcpy(x, h->attrs, sizeof(tmp));
+ memcpy(h->attrs, &tmp, sizeof(tmp));
+ return;
+ }
+ }
+}
+
+static const char *find_ea_prefix(int index)
+{
+ struct ea_name_index *e;
+
+ for (e = ea_names; e->name; e++)
+ if (e->index == index)
+ return e->name;
+
+ return NULL;
+}
+
+static int find_ea_index(const char *fullname, char **name, int *index)
+{
+ struct ea_name_index *e;
+
+ for (e = ea_names; e->name; e++) {
+ if (memcmp(fullname, e->name, strlen(e->name)) == 0) {
+ *name = (char *)fullname + strlen(e->name);
+ *index = e->index;
+ return 1;
+ }
+ }
+ return 0;
+}
+
+errcode_t ext2fs_free_ext_attr(ext2_filsys fs, ext2_ino_t ino,
+ struct ext2_inode_large *inode)
+{
+ struct ext2_ext_attr_header *header;
+ void *block_buf = NULL;
+ blk64_t blk;
+ errcode_t err;
+ struct ext2_inode_large i;
+
+ /* Read inode? */
+ if (inode == NULL) {
+ err = ext2fs_read_inode_full(fs, ino, (struct ext2_inode *)&i,
+ sizeof(struct ext2_inode_large));
+ if (err)
+ return err;
+ inode = &i;
+ }
+
+ /* Do we already have an EA block? */
+ blk = ext2fs_file_acl_block(fs, (struct ext2_inode *)inode);
+ if (blk == 0)
+ return 0;
+
+ /* Find block, zero it, write back */
+ if ((blk < fs->super->s_first_data_block) ||
+ (blk >= ext2fs_blocks_count(fs->super))) {
+ err = EXT2_ET_BAD_EA_BLOCK_NUM;
+ goto out;
+ }
+
+ err = ext2fs_get_mem(fs->blocksize, &block_buf);
+ if (err)
+ goto out;
+
+ err = ext2fs_read_ext_attr3(fs, blk, block_buf, ino);
+ if (err)
+ goto out2;
+
+ /* We only know how to deal with v2 EA blocks */
+ header = (struct ext2_ext_attr_header *) block_buf;
+ if (header->h_magic != EXT2_EXT_ATTR_MAGIC) {
+ err = EXT2_ET_BAD_EA_HEADER;
+ goto out2;
+ }
+
+ header->h_refcount--;
+ err = ext2fs_write_ext_attr3(fs, blk, block_buf, ino);
+ if (err)
+ goto out2;
+
+ /* Erase link to block */
+ ext2fs_file_acl_block_set(fs, (struct ext2_inode *)inode, 0);
+ if (header->h_refcount == 0)
+ ext2fs_block_alloc_stats2(fs, blk, -1);
+ err = ext2fs_iblk_sub_blocks(fs, (struct ext2_inode *)inode, 1);
+ if (err)
+ goto out2;
+
+ /* Write inode? */
+ if (inode == &i) {
+ err = ext2fs_write_inode_full(fs, ino, (struct ext2_inode *)&i,
+ sizeof(struct ext2_inode_large));
+ if (err)
+ goto out2;
+ }
+
+out2:
+ ext2fs_free_mem(&block_buf);
+out:
+ return err;
+}
+
+static errcode_t prep_ea_block_for_write(ext2_filsys fs, ext2_ino_t ino,
+ struct ext2_inode_large *inode)
+{
+ struct ext2_ext_attr_header *header;
+ void *block_buf = NULL;
+ dgrp_t grp;
+ blk64_t blk, goal;
+ errcode_t err;
+
+ /* Do we already have an EA block? */
+ blk = ext2fs_file_acl_block(fs, (struct ext2_inode *)inode);
+ if (blk != 0) {
+ if ((blk < fs->super->s_first_data_block) ||
+ (blk >= ext2fs_blocks_count(fs->super))) {
+ err = EXT2_ET_BAD_EA_BLOCK_NUM;
+ goto out;
+ }
+
+ err = ext2fs_get_mem(fs->blocksize, &block_buf);
+ if (err)
+ goto out;
+
+ err = ext2fs_read_ext_attr3(fs, blk, block_buf, ino);
+ if (err)
+ goto out2;
+
+ /* We only know how to deal with v2 EA blocks */
+ header = (struct ext2_ext_attr_header *) block_buf;
+ if (header->h_magic != EXT2_EXT_ATTR_MAGIC) {
+ err = EXT2_ET_BAD_EA_HEADER;
+ goto out2;
+ }
+
+ /* Single-user block. We're done here. */
+ if (header->h_refcount == 1)
+ goto out2;
+
+ /* We need to CoW the block. */
+ header->h_refcount--;
+ err = ext2fs_write_ext_attr3(fs, blk, block_buf, ino);
+ if (err)
+ goto out2;
+ } else {
+ /* No block, we must increment i_blocks */
+ err = ext2fs_iblk_add_blocks(fs, (struct ext2_inode *)inode,
+ 1);
+ if (err)
+ goto out;
+ }
+
+ /* Allocate a block */
+ grp = ext2fs_group_of_ino(fs, ino);
+ goal = ext2fs_inode_table_loc(fs, grp);
+ err = ext2fs_alloc_block2(fs, goal, NULL, &blk);
+ if (err)
+ goto out2;
+ ext2fs_file_acl_block_set(fs, (struct ext2_inode *)inode, blk);
+out2:
+ if (block_buf)
+ ext2fs_free_mem(&block_buf);
+out:
+ return err;
+}
+
+
+static errcode_t write_xattrs_to_buffer(struct ext2_xattr_handle *handle,
+ struct ext2_xattr **pos,
+ void *entries_start,
+ unsigned int storage_size,
+ unsigned int value_offset_correction)
+{
+ struct ext2_xattr *x = *pos;
+ struct ext2_ext_attr_entry *e = entries_start;
+ void *end = entries_start + storage_size;
+ char *shortname;
+ unsigned int entry_size, value_size;
+ int idx, ret;
+
+ memset(entries_start, 0, storage_size);
+ /* For all remaining x... */
+ for (; x < handle->attrs + handle->length; x++) {
+ if (!x->name)
+ continue;
+
+ /* Calculate index and shortname position */
+ shortname = x->name;
+ ret = find_ea_index(x->name, &shortname, &idx);
+
+ /* Calculate entry and value size */
+ entry_size = (sizeof(*e) + strlen(shortname) +
+ EXT2_EXT_ATTR_PAD - 1) &
+ ~(EXT2_EXT_ATTR_PAD - 1);
+ value_size = ((x->value_len + EXT2_EXT_ATTR_PAD - 1) /
+ EXT2_EXT_ATTR_PAD) * EXT2_EXT_ATTR_PAD;
+
+ /*
+ * Would entry collide with value?
+ * Note that we must leave sufficient room for a (u32)0 to
+ * mark the end of the entries.
+ */
+ if ((void *)e + entry_size + sizeof(__u32) > end - value_size)
+ break;
+
+ /* Fill out e appropriately */
+ e->e_name_len = strlen(shortname);
+ e->e_name_index = (ret ? idx : 0);
+ e->e_value_offs = end - value_size - (void *)entries_start +
+ value_offset_correction;
+ e->e_value_block = 0;
+ e->e_value_size = x->value_len;
+
+ /* Store name and value */
+ end -= value_size;
+ memcpy((void *)e + sizeof(*e), shortname, e->e_name_len);
+ memcpy(end, x->value, e->e_value_size);
+
+ e->e_hash = ext2fs_ext_attr_hash_entry(e, end);
+
+ e = EXT2_EXT_ATTR_NEXT(e);
+ *(__u32 *)e = 0;
+ }
+ *pos = x;
+
+ return 0;
+}
+
+errcode_t ext2fs_xattrs_write(struct ext2_xattr_handle *handle)
+{
+ struct ext2_xattr *x;
+ struct ext2_inode_large *inode;
+ void *start, *block_buf = NULL;
+ struct ext2_ext_attr_header *header;
+ __u32 ea_inode_magic;
+ blk64_t blk;
+ unsigned int storage_size;
+ unsigned int i;
+ errcode_t err;
+
+ EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EA_HANDLE);
+ i = EXT2_INODE_SIZE(handle->fs->super);
+ if (i < sizeof(*inode))
+ i = sizeof(*inode);
+ err = ext2fs_get_memzero(i, &inode);
+ if (err)
+ return err;
+
+ err = ext2fs_read_inode_full(handle->fs, handle->ino,
+ (struct ext2_inode *)inode,
+ EXT2_INODE_SIZE(handle->fs->super));
+ if (err)
+ goto out;
+
+ move_inline_data_to_front(handle);
+
+ x = handle->attrs;
+ /* Does the inode have size for EA? */
+ if (EXT2_INODE_SIZE(handle->fs->super) <= EXT2_GOOD_OLD_INODE_SIZE +
+ inode->i_extra_isize +
+ sizeof(__u32))
+ goto write_ea_block;
+
+ /* Write the inode EA */
+ ea_inode_magic = EXT2_EXT_ATTR_MAGIC;
+ memcpy(((char *) inode) + EXT2_GOOD_OLD_INODE_SIZE +
+ inode->i_extra_isize, &ea_inode_magic, sizeof(__u32));
+ storage_size = EXT2_INODE_SIZE(handle->fs->super) -
+ EXT2_GOOD_OLD_INODE_SIZE - inode->i_extra_isize -
+ sizeof(__u32);
+ start = ((char *) inode) + EXT2_GOOD_OLD_INODE_SIZE +
+ inode->i_extra_isize + sizeof(__u32);
+
+ err = write_xattrs_to_buffer(handle, &x, start, storage_size, 0);
+ if (err)
+ goto out;
+
+ /* Are we done? */
+ if (x == handle->attrs + handle->length)
+ goto skip_ea_block;
+
+write_ea_block:
+ /* Write the EA block */
+ err = ext2fs_get_mem(handle->fs->blocksize, &block_buf);
+ if (err)
+ goto out;
+
+ storage_size = handle->fs->blocksize -
+ sizeof(struct ext2_ext_attr_header);
+ start = block_buf + sizeof(struct ext2_ext_attr_header);
+
+ err = write_xattrs_to_buffer(handle, &x, start, storage_size,
+ (void *)start - block_buf);
+ if (err)
+ goto out2;
+
+ if (x < handle->attrs + handle->length) {
+ err = EXT2_ET_EA_NO_SPACE;
+ goto out2;
+ }
+
+ /* Write a header on the EA block */
+ header = block_buf;
+ header->h_magic = EXT2_EXT_ATTR_MAGIC;
+ header->h_refcount = 1;
+ header->h_blocks = 1;
+
+ /* Get a new block for writing */
+ err = prep_ea_block_for_write(handle->fs, handle->ino, inode);
+ if (err)
+ goto out2;
+
+ /* Finally, write the new EA block */
+ blk = ext2fs_file_acl_block(handle->fs,
+ (struct ext2_inode *)inode);
+ err = ext2fs_write_ext_attr3(handle->fs, blk, block_buf,
+ handle->ino);
+ if (err)
+ goto out2;
+
+skip_ea_block:
+ blk = ext2fs_file_acl_block(handle->fs, (struct ext2_inode *)inode);
+ if (!block_buf && blk) {
+ /* xattrs shrunk, free the block */
+ err = ext2fs_free_ext_attr(handle->fs, handle->ino, inode);
+ if (err)
+ goto out;
+ }
+
+ /* Write the inode */
+ err = ext2fs_write_inode_full(handle->fs, handle->ino,
+ (struct ext2_inode *)inode,
+ EXT2_INODE_SIZE(handle->fs->super));
+ if (err)
+ goto out2;
+
+out2:
+ ext2fs_free_mem(&block_buf);
+out:
+ ext2fs_free_mem(&inode);
+ handle->dirty = 0;
+ return err;
+}
+
+static errcode_t read_xattrs_from_buffer(struct ext2_xattr_handle *handle,
+ struct ext2_ext_attr_entry *entries,
+ unsigned int storage_size,
+ void *value_start,
+ size_t *nr_read)
+{
+ struct ext2_xattr *x;
+ struct ext2_ext_attr_entry *entry, *end;
+ const char *prefix;
+ unsigned int remain, prefix_len;
+ errcode_t err;
+ unsigned int values_size = storage_size +
+ ((char *)entries - (char *)value_start);
+
+ x = handle->attrs;
+ while (x->name)
+ x++;
+
+ /* find the end */
+ end = entries;
+ remain = storage_size;
+ while (remain >= sizeof(struct ext2_ext_attr_entry) &&
+ !EXT2_EXT_IS_LAST_ENTRY(end)) {
+
+ /* header eats this space */
+ remain -= sizeof(struct ext2_ext_attr_entry);
+
+ /* is attribute name valid? */
+ if (EXT2_EXT_ATTR_SIZE(end->e_name_len) > remain)
+ return EXT2_ET_EA_BAD_NAME_LEN;
+
+ /* attribute len eats this space */
+ remain -= EXT2_EXT_ATTR_SIZE(end->e_name_len);
+ end = EXT2_EXT_ATTR_NEXT(end);
+ }
+
+ entry = entries;
+ remain = storage_size;
+ while (remain >= sizeof(struct ext2_ext_attr_entry) &&
+ !EXT2_EXT_IS_LAST_ENTRY(entry)) {
+ __u32 hash;
+
+ /* header eats this space */
+ remain -= sizeof(struct ext2_ext_attr_entry);
+
+ /* attribute len eats this space */
+ remain -= EXT2_EXT_ATTR_SIZE(entry->e_name_len);
+
+ /* check value size */
+ if (entry->e_value_size > remain)
+ return EXT2_ET_EA_BAD_VALUE_SIZE;
+
+ if (entry->e_value_offs + entry->e_value_size > values_size)
+ return EXT2_ET_EA_BAD_VALUE_OFFSET;
+
+ if (entry->e_value_size > 0 &&
+ value_start + entry->e_value_offs <
+ (void *)end + sizeof(__u32))
+ return EXT2_ET_EA_BAD_VALUE_OFFSET;
+
+ /* e_value_block must be 0 in inode's ea */
+ if (entry->e_value_block != 0)
+ return EXT2_ET_BAD_EA_BLOCK_NUM;
+
+ hash = ext2fs_ext_attr_hash_entry(entry, value_start +
+ entry->e_value_offs);
+
+ /* e_hash may be 0 in older inode's ea */
+ if (entry->e_hash != 0 && entry->e_hash != hash)
+ return EXT2_ET_BAD_EA_HASH;
+
+ remain -= entry->e_value_size;
+
+ /* Allocate space for more attrs? */
+ if (x == handle->attrs + handle->length) {
+ err = ext2fs_xattrs_expand(handle, 4);
+ if (err)
+ return err;
+ x = handle->attrs + handle->length - 4;
+ }
+
+ /* Extract name/value */
+ prefix = find_ea_prefix(entry->e_name_index);
+ prefix_len = (prefix ? strlen(prefix) : 0);
+ err = ext2fs_get_memzero(entry->e_name_len + prefix_len + 1,
+ &x->name);
+ if (err)
+ return err;
+ if (prefix)
+ memcpy(x->name, prefix, prefix_len);
+ if (entry->e_name_len)
+ memcpy(x->name + prefix_len,
+ (void *)entry + sizeof(*entry),
+ entry->e_name_len);
+
+ err = ext2fs_get_mem(entry->e_value_size, &x->value);
+ if (err)
+ return err;
+ x->value_len = entry->e_value_size;
+ memcpy(x->value, value_start + entry->e_value_offs,
+ entry->e_value_size);
+ x++;
+ (*nr_read)++;
+ entry = EXT2_EXT_ATTR_NEXT(entry);
+ }
+
+ return 0;
+}
+
+static void xattrs_free_keys(struct ext2_xattr_handle *h)
+{
+ struct ext2_xattr *a = h->attrs;
+ size_t i;
+
+ for (i = 0; i < h->length; i++) {
+ if (a[i].name)
+ ext2fs_free_mem(&a[i].name);
+ if (a[i].value)
+ ext2fs_free_mem(&a[i].value);
+ }
+ h->count = 0;
+}
+
+errcode_t ext2fs_xattrs_read(struct ext2_xattr_handle *handle)
+{
+ struct ext2_inode_large *inode;
+ struct ext2_ext_attr_header *header;
+ __u32 ea_inode_magic;
+ unsigned int storage_size;
+ void *start, *block_buf = NULL;
+ blk64_t blk;
+ int i;
+ errcode_t err;
+
+ EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EA_HANDLE);
+ i = EXT2_INODE_SIZE(handle->fs->super);
+ if (i < sizeof(*inode))
+ i = sizeof(*inode);
+ err = ext2fs_get_memzero(i, &inode);
+ if (err)
+ return err;
+
+ err = ext2fs_read_inode_full(handle->fs, handle->ino,
+ (struct ext2_inode *)inode,
+ EXT2_INODE_SIZE(handle->fs->super));
+ if (err)
+ goto out;
+
+ xattrs_free_keys(handle);
+
+ /* Does the inode have size for EA? */
+ if (EXT2_INODE_SIZE(handle->fs->super) <= EXT2_GOOD_OLD_INODE_SIZE +
+ inode->i_extra_isize +
+ sizeof(__u32))
+ goto read_ea_block;
+
+ /* Look for EA in the inode */
+ memcpy(&ea_inode_magic, ((char *) inode) + EXT2_GOOD_OLD_INODE_SIZE +
+ inode->i_extra_isize, sizeof(__u32));
+ if (ea_inode_magic == EXT2_EXT_ATTR_MAGIC) {
+ storage_size = EXT2_INODE_SIZE(handle->fs->super) -
+ EXT2_GOOD_OLD_INODE_SIZE - inode->i_extra_isize -
+ sizeof(__u32);
+ start = ((char *) inode) + EXT2_GOOD_OLD_INODE_SIZE +
+ inode->i_extra_isize + sizeof(__u32);
+
+ err = read_xattrs_from_buffer(handle, start, storage_size,
+ start, &handle->count);
+ if (err)
+ goto out;
+ }
+
+read_ea_block:
+ /* Look for EA in a separate EA block */
+ blk = ext2fs_file_acl_block(handle->fs, (struct ext2_inode *)inode);
+ if (blk != 0) {
+ if ((blk < handle->fs->super->s_first_data_block) ||
+ (blk >= ext2fs_blocks_count(handle->fs->super))) {
+ err = EXT2_ET_BAD_EA_BLOCK_NUM;
+ goto out;
+ }
+
+ err = ext2fs_get_mem(handle->fs->blocksize, &block_buf);
+ if (err)
+ goto out;
+
+ err = ext2fs_read_ext_attr3(handle->fs, blk, block_buf,
+ handle->ino);
+ if (err)
+ goto out3;
+
+ /* We only know how to deal with v2 EA blocks */
+ header = (struct ext2_ext_attr_header *) block_buf;
+ if (header->h_magic != EXT2_EXT_ATTR_MAGIC) {
+ err = EXT2_ET_BAD_EA_HEADER;
+ goto out3;
+ }
+
+ /* Read EAs */
+ storage_size = handle->fs->blocksize -
+ sizeof(struct ext2_ext_attr_header);
+ start = block_buf + sizeof(struct ext2_ext_attr_header);
+ err = read_xattrs_from_buffer(handle, start, storage_size,
+ block_buf, &handle->count);
+ if (err)
+ goto out3;
+
+ ext2fs_free_mem(&block_buf);
+ }
+
+ ext2fs_free_mem(&block_buf);
+ ext2fs_free_mem(&inode);
+ return 0;
+
+out3:
+ ext2fs_free_mem(&block_buf);
+out:
+ ext2fs_free_mem(&inode);
+ return err;
+}
+
+errcode_t ext2fs_xattrs_iterate(struct ext2_xattr_handle *h,
+ int (*func)(char *name, char *value,
+ size_t value_len, void *data),
+ void *data)
+{
+ struct ext2_xattr *x;
+ int ret;
+
+ EXT2_CHECK_MAGIC(h, EXT2_ET_MAGIC_EA_HANDLE);
+ for (x = h->attrs; x < h->attrs + h->length; x++) {
+ if (!x->name)
+ continue;
+
+ ret = func(x->name, x->value, x->value_len, data);
+ if (ret & XATTR_CHANGED)
+ h->dirty = 1;
+ if (ret & XATTR_ABORT)
+ return 0;
+ }
+
+ return 0;
+}
+
+errcode_t ext2fs_xattr_get(struct ext2_xattr_handle *h, const char *key,
+ void **value, size_t *value_len)
+{
+ struct ext2_xattr *x;
+ void *val;
+ errcode_t err;
+
+ EXT2_CHECK_MAGIC(h, EXT2_ET_MAGIC_EA_HANDLE);
+ for (x = h->attrs; x < h->attrs + h->length; x++) {
+ if (!x->name)
+ continue;
+
+ if (strcmp(x->name, key) == 0) {
+ err = ext2fs_get_mem(x->value_len, &val);
+ if (err)
+ return err;
+ memcpy(val, x->value, x->value_len);
+ *value = val;
+ *value_len = x->value_len;
+ return 0;
+ }
+ }
+
+ return EXT2_ET_EA_KEY_NOT_FOUND;
+}
+
+errcode_t ext2fs_xattr_inode_max_size(ext2_filsys fs, ext2_ino_t ino,
+ size_t *size)
+{
+ struct ext2_ext_attr_entry *entry;
+ struct ext2_inode_large *inode;
+ __u32 ea_inode_magic;
+ unsigned int minoff;
+ void *start;
+ int i;
+ errcode_t err;
+
+ i = EXT2_INODE_SIZE(fs->super);
+ if (i < sizeof(*inode))
+ i = sizeof(*inode);
+ err = ext2fs_get_memzero(i, &inode);
+ if (err)
+ return err;
+
+ err = ext2fs_read_inode_full(fs, ino, (struct ext2_inode *)inode,
+ EXT2_INODE_SIZE(fs->super));
+ if (err)
+ goto out;
+
+ /* Does the inode have size for EA? */
+ if (EXT2_INODE_SIZE(fs->super) <= EXT2_GOOD_OLD_INODE_SIZE +
+ inode->i_extra_isize +
+ sizeof(__u32)) {
+ err = EXT2_ET_INLINE_DATA_NO_SPACE;
+ goto out;
+ }
+
+ minoff = EXT2_INODE_SIZE(fs->super) - sizeof(*inode) - sizeof(__u32);
+ memcpy(&ea_inode_magic, ((char *) inode) + EXT2_GOOD_OLD_INODE_SIZE +
+ inode->i_extra_isize, sizeof(__u32));
+ if (ea_inode_magic == EXT2_EXT_ATTR_MAGIC) {
+ /* has xattrs. calculate the size */
+ start= ((char *) inode) + EXT2_GOOD_OLD_INODE_SIZE +
+ inode->i_extra_isize + sizeof(__u32);
+ entry = start;
+ while (!EXT2_EXT_IS_LAST_ENTRY(entry)) {
+ if (!entry->e_value_block && entry->e_value_size) {
+ unsigned int offs = entry->e_value_offs;
+ if (offs < minoff)
+ minoff = offs;
+ }
+ entry = EXT2_EXT_ATTR_NEXT(entry);
+ }
+ *size = minoff - ((char *)entry - (char *)start) - sizeof(__u32);
+ } else {
+ /* no xattr. return a maximum size */
+ *size = EXT2_EXT_ATTR_SIZE(minoff -
+ EXT2_EXT_ATTR_LEN(strlen("data")) -
+ EXT2_EXT_ATTR_ROUND - sizeof(__u32));
+ }
+
+out:
+ ext2fs_free_mem(&inode);
+ return err;
+}
+
+errcode_t ext2fs_xattr_set(struct ext2_xattr_handle *handle,
+ const char *key,
+ const void *value,
+ size_t value_len)
+{
+ struct ext2_xattr *x, *last_empty;
+ char *new_value;
+ errcode_t err;
+
+ EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EA_HANDLE);
+ last_empty = NULL;
+ for (x = handle->attrs; x < handle->attrs + handle->length; x++) {
+ if (!x->name) {
+ last_empty = x;
+ continue;
+ }
+
+ /* Replace xattr */
+ if (strcmp(x->name, key) == 0) {
+ err = ext2fs_get_mem(value_len, &new_value);
+ if (err)
+ return err;
+ memcpy(new_value, value, value_len);
+ ext2fs_free_mem(&x->value);
+ x->value = new_value;
+ x->value_len = value_len;
+ handle->dirty = 1;
+ return 0;
+ }
+ }
+
+ /* Add attr to empty slot */
+ if (last_empty) {
+ err = ext2fs_get_mem(strlen(key) + 1, &last_empty->name);
+ if (err)
+ return err;
+ strcpy(last_empty->name, key);
+
+ err = ext2fs_get_mem(value_len, &last_empty->value);
+ if (err)
+ return err;
+ memcpy(last_empty->value, value, value_len);
+ last_empty->value_len = value_len;
+ handle->dirty = 1;
+ handle->count++;
+ return 0;
+ }
+
+ /* Expand array, append slot */
+ err = ext2fs_xattrs_expand(handle, 4);
+ if (err)
+ return err;
+
+ x = handle->attrs + handle->length - 4;
+ err = ext2fs_get_mem(strlen(key) + 1, &x->name);
+ if (err)
+ return err;
+ strcpy(x->name, key);
+
+ err = ext2fs_get_mem(value_len, &x->value);
+ if (err)
+ return err;
+ memcpy(x->value, value, value_len);
+ x->value_len = value_len;
+ handle->dirty = 1;
+ handle->count++;
+ return 0;
+}
+
+errcode_t ext2fs_xattr_remove(struct ext2_xattr_handle *handle,
+ const char *key)
+{
+ struct ext2_xattr *x;
+
+ EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EA_HANDLE);
+ for (x = handle->attrs; x < handle->attrs + handle->length; x++) {
+ if (!x->name)
+ continue;
+
+ if (strcmp(x->name, key) == 0) {
+ ext2fs_free_mem(&x->name);
+ ext2fs_free_mem(&x->value);
+ x->value_len = 0;
+ handle->dirty = 1;
+ handle->count--;
+ return 0;
+ }
+ }
+
+ /* no key found, success! */
+ return 0;
+}
+
+errcode_t ext2fs_xattrs_open(ext2_filsys fs, ext2_ino_t ino,
+ struct ext2_xattr_handle **handle)
+{
+ struct ext2_xattr_handle *h;
+ errcode_t err;
+
+ if (!EXT2_HAS_COMPAT_FEATURE(fs->super,
+ EXT2_FEATURE_COMPAT_EXT_ATTR) &&
+ !EXT2_HAS_INCOMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_INCOMPAT_INLINE_DATA))
+ return EXT2_ET_MISSING_EA_FEATURE;
+
+ err = ext2fs_get_memzero(sizeof(*h), &h);
+ if (err)
+ return err;
+
+ h->magic = EXT2_ET_MAGIC_EA_HANDLE;
+ h->length = 4;
+ err = ext2fs_get_arrayzero(h->length, sizeof(struct ext2_xattr),
+ &h->attrs);
+ if (err) {
+ ext2fs_free_mem(&h);
+ return err;
+ }
+ h->count = 0;
+ h->ino = ino;
+ h->fs = fs;
+ *handle = h;
+ return 0;
+}
+
+errcode_t ext2fs_xattrs_close(struct ext2_xattr_handle **handle)
+{
+ struct ext2_xattr_handle *h = *handle;
+ errcode_t err;
+
+ EXT2_CHECK_MAGIC(h, EXT2_ET_MAGIC_EA_HANDLE);
+ if (h->dirty) {
+ err = ext2fs_xattrs_write(h);
+ if (err)
+ return err;
+ }
+
+ xattrs_free_keys(h);
+ ext2fs_free_mem(&h->attrs);
+ ext2fs_free_mem(handle);
+ return 0;
+}
+
+errcode_t ext2fs_xattrs_count(struct ext2_xattr_handle *handle, size_t *count)
+{
+ EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EA_HANDLE);
+ *count = handle->count;
+ return 0;
+}