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- #include <linux/capability.h>
- #include <linux/fs.h>
- #include <linux/posix_acl.h>
- #include "reiserfs.h"
- #include <linux/errno.h>
- #include <linux/pagemap.h>
- #include <linux/xattr.h>
- #include <linux/slab.h>
- #include <linux/posix_acl_xattr.h>
- #include "xattr.h"
- #include "acl.h"
- #include <linux/uaccess.h>
- static int __reiserfs_set_acl(struct reiserfs_transaction_handle *th,
- struct inode *inode, int type,
- struct posix_acl *acl);
- int
- reiserfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
- {
- int error, error2;
- struct reiserfs_transaction_handle th;
- size_t jcreate_blocks;
- int size = acl ? posix_acl_xattr_size(acl->a_count) : 0;
- /*
- * Pessimism: We can't assume that anything from the xattr root up
- * has been created.
- */
- jcreate_blocks = reiserfs_xattr_jcreate_nblocks(inode) +
- reiserfs_xattr_nblocks(inode, size) * 2;
- reiserfs_write_lock(inode->i_sb);
- error = journal_begin(&th, inode->i_sb, jcreate_blocks);
- reiserfs_write_unlock(inode->i_sb);
- if (error == 0) {
- if (type == ACL_TYPE_ACCESS && acl) {
- error = posix_acl_update_mode(inode, &inode->i_mode,
- &acl);
- if (error)
- goto unlock;
- }
- error = __reiserfs_set_acl(&th, inode, type, acl);
- unlock:
- reiserfs_write_lock(inode->i_sb);
- error2 = journal_end(&th);
- reiserfs_write_unlock(inode->i_sb);
- if (error2)
- error = error2;
- }
- return error;
- }
- /*
- * Convert from filesystem to in-memory representation.
- */
- static struct posix_acl *reiserfs_posix_acl_from_disk(const void *value, size_t size)
- {
- const char *end = (char *)value + size;
- int n, count;
- struct posix_acl *acl;
- if (!value)
- return NULL;
- if (size < sizeof(reiserfs_acl_header))
- return ERR_PTR(-EINVAL);
- if (((reiserfs_acl_header *) value)->a_version !=
- cpu_to_le32(REISERFS_ACL_VERSION))
- return ERR_PTR(-EINVAL);
- value = (char *)value + sizeof(reiserfs_acl_header);
- count = reiserfs_acl_count(size);
- if (count < 0)
- return ERR_PTR(-EINVAL);
- if (count == 0)
- return NULL;
- acl = posix_acl_alloc(count, GFP_NOFS);
- if (!acl)
- return ERR_PTR(-ENOMEM);
- for (n = 0; n < count; n++) {
- reiserfs_acl_entry *entry = (reiserfs_acl_entry *) value;
- if ((char *)value + sizeof(reiserfs_acl_entry_short) > end)
- goto fail;
- acl->a_entries[n].e_tag = le16_to_cpu(entry->e_tag);
- acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm);
- switch (acl->a_entries[n].e_tag) {
- case ACL_USER_OBJ:
- case ACL_GROUP_OBJ:
- case ACL_MASK:
- case ACL_OTHER:
- value = (char *)value +
- sizeof(reiserfs_acl_entry_short);
- break;
- case ACL_USER:
- value = (char *)value + sizeof(reiserfs_acl_entry);
- if ((char *)value > end)
- goto fail;
- acl->a_entries[n].e_uid =
- make_kuid(&init_user_ns,
- le32_to_cpu(entry->e_id));
- break;
- case ACL_GROUP:
- value = (char *)value + sizeof(reiserfs_acl_entry);
- if ((char *)value > end)
- goto fail;
- acl->a_entries[n].e_gid =
- make_kgid(&init_user_ns,
- le32_to_cpu(entry->e_id));
- break;
- default:
- goto fail;
- }
- }
- if (value != end)
- goto fail;
- return acl;
- fail:
- posix_acl_release(acl);
- return ERR_PTR(-EINVAL);
- }
- /*
- * Convert from in-memory to filesystem representation.
- */
- static void *reiserfs_posix_acl_to_disk(const struct posix_acl *acl, size_t * size)
- {
- reiserfs_acl_header *ext_acl;
- char *e;
- int n;
- *size = reiserfs_acl_size(acl->a_count);
- ext_acl = kmalloc(sizeof(reiserfs_acl_header) +
- acl->a_count *
- sizeof(reiserfs_acl_entry),
- GFP_NOFS);
- if (!ext_acl)
- return ERR_PTR(-ENOMEM);
- ext_acl->a_version = cpu_to_le32(REISERFS_ACL_VERSION);
- e = (char *)ext_acl + sizeof(reiserfs_acl_header);
- for (n = 0; n < acl->a_count; n++) {
- const struct posix_acl_entry *acl_e = &acl->a_entries[n];
- reiserfs_acl_entry *entry = (reiserfs_acl_entry *) e;
- entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag);
- entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
- switch (acl->a_entries[n].e_tag) {
- case ACL_USER:
- entry->e_id = cpu_to_le32(
- from_kuid(&init_user_ns, acl_e->e_uid));
- e += sizeof(reiserfs_acl_entry);
- break;
- case ACL_GROUP:
- entry->e_id = cpu_to_le32(
- from_kgid(&init_user_ns, acl_e->e_gid));
- e += sizeof(reiserfs_acl_entry);
- break;
- case ACL_USER_OBJ:
- case ACL_GROUP_OBJ:
- case ACL_MASK:
- case ACL_OTHER:
- e += sizeof(reiserfs_acl_entry_short);
- break;
- default:
- goto fail;
- }
- }
- return (char *)ext_acl;
- fail:
- kfree(ext_acl);
- return ERR_PTR(-EINVAL);
- }
- /*
- * Inode operation get_posix_acl().
- *
- * inode->i_mutex: down
- * BKL held [before 2.5.x]
- */
- struct posix_acl *reiserfs_get_acl(struct inode *inode, int type)
- {
- char *name, *value;
- struct posix_acl *acl;
- int size;
- int retval;
- switch (type) {
- case ACL_TYPE_ACCESS:
- name = POSIX_ACL_XATTR_ACCESS;
- break;
- case ACL_TYPE_DEFAULT:
- name = POSIX_ACL_XATTR_DEFAULT;
- break;
- default:
- BUG();
- }
- size = reiserfs_xattr_get(inode, name, NULL, 0);
- if (size < 0) {
- if (size == -ENODATA || size == -ENOSYS) {
- set_cached_acl(inode, type, NULL);
- return NULL;
- }
- return ERR_PTR(size);
- }
- value = kmalloc(size, GFP_NOFS);
- if (!value)
- return ERR_PTR(-ENOMEM);
- retval = reiserfs_xattr_get(inode, name, value, size);
- if (retval == -ENODATA || retval == -ENOSYS) {
- /*
- * This shouldn't actually happen as it should have
- * been caught above.. but just in case
- */
- acl = NULL;
- } else if (retval < 0) {
- acl = ERR_PTR(retval);
- } else {
- acl = reiserfs_posix_acl_from_disk(value, retval);
- }
- if (!IS_ERR(acl))
- set_cached_acl(inode, type, acl);
- kfree(value);
- return acl;
- }
- /*
- * Inode operation set_posix_acl().
- *
- * inode->i_mutex: down
- * BKL held [before 2.5.x]
- */
- static int
- __reiserfs_set_acl(struct reiserfs_transaction_handle *th, struct inode *inode,
- int type, struct posix_acl *acl)
- {
- char *name;
- void *value = NULL;
- size_t size = 0;
- int error;
- switch (type) {
- case ACL_TYPE_ACCESS:
- name = POSIX_ACL_XATTR_ACCESS;
- break;
- case ACL_TYPE_DEFAULT:
- name = POSIX_ACL_XATTR_DEFAULT;
- if (!S_ISDIR(inode->i_mode))
- return acl ? -EACCES : 0;
- break;
- default:
- return -EINVAL;
- }
- if (acl) {
- value = reiserfs_posix_acl_to_disk(acl, &size);
- if (IS_ERR(value))
- return (int)PTR_ERR(value);
- }
- error = reiserfs_xattr_set_handle(th, inode, name, value, size, 0);
- /*
- * Ensure that the inode gets dirtied if we're only using
- * the mode bits and an old ACL didn't exist. We don't need
- * to check if the inode is hashed here since we won't get
- * called by reiserfs_inherit_default_acl().
- */
- if (error == -ENODATA) {
- error = 0;
- if (type == ACL_TYPE_ACCESS) {
- inode->i_ctime = CURRENT_TIME_SEC;
- mark_inode_dirty(inode);
- }
- }
- kfree(value);
- if (!error)
- set_cached_acl(inode, type, acl);
- return error;
- }
- /*
- * dir->i_mutex: locked,
- * inode is new and not released into the wild yet
- */
- int
- reiserfs_inherit_default_acl(struct reiserfs_transaction_handle *th,
- struct inode *dir, struct dentry *dentry,
- struct inode *inode)
- {
- struct posix_acl *default_acl, *acl;
- int err = 0;
- /* ACLs only get applied to files and directories */
- if (S_ISLNK(inode->i_mode))
- return 0;
- /*
- * ACLs can only be used on "new" objects, so if it's an old object
- * there is nothing to inherit from
- */
- if (get_inode_sd_version(dir) == STAT_DATA_V1)
- goto apply_umask;
- /*
- * Don't apply ACLs to objects in the .reiserfs_priv tree.. This
- * would be useless since permissions are ignored, and a pain because
- * it introduces locking cycles
- */
- if (IS_PRIVATE(dir)) {
- inode->i_flags |= S_PRIVATE;
- goto apply_umask;
- }
- err = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
- if (err)
- return err;
- if (default_acl) {
- err = __reiserfs_set_acl(th, inode, ACL_TYPE_DEFAULT,
- default_acl);
- posix_acl_release(default_acl);
- }
- if (acl) {
- if (!err)
- err = __reiserfs_set_acl(th, inode, ACL_TYPE_ACCESS,
- acl);
- posix_acl_release(acl);
- }
- return err;
- apply_umask:
- /* no ACL, apply umask */
- inode->i_mode &= ~current_umask();
- return err;
- }
- /* This is used to cache the default acl before a new object is created.
- * The biggest reason for this is to get an idea of how many blocks will
- * actually be required for the create operation if we must inherit an ACL.
- * An ACL write can add up to 3 object creations and an additional file write
- * so we'd prefer not to reserve that many blocks in the journal if we can.
- * It also has the advantage of not loading the ACL with a transaction open,
- * this may seem silly, but if the owner of the directory is doing the
- * creation, the ACL may not be loaded since the permissions wouldn't require
- * it.
- * We return the number of blocks required for the transaction.
- */
- int reiserfs_cache_default_acl(struct inode *inode)
- {
- struct posix_acl *acl;
- int nblocks = 0;
- if (IS_PRIVATE(inode))
- return 0;
- acl = reiserfs_get_acl(inode, ACL_TYPE_DEFAULT);
- if (acl && !IS_ERR(acl)) {
- int size = reiserfs_acl_size(acl->a_count);
- /* Other xattrs can be created during inode creation. We don't
- * want to claim too many blocks, so we check to see if we
- * we need to create the tree to the xattrs, and then we
- * just want two files. */
- nblocks = reiserfs_xattr_jcreate_nblocks(inode);
- nblocks += JOURNAL_BLOCKS_PER_OBJECT(inode->i_sb);
- REISERFS_I(inode)->i_flags |= i_has_xattr_dir;
- /* We need to account for writes + bitmaps for two files */
- nblocks += reiserfs_xattr_nblocks(inode, size) * 4;
- posix_acl_release(acl);
- }
- return nblocks;
- }
- /*
- * Called under i_mutex
- */
- int reiserfs_acl_chmod(struct inode *inode)
- {
- if (IS_PRIVATE(inode))
- return 0;
- if (get_inode_sd_version(inode) == STAT_DATA_V1 ||
- !reiserfs_posixacl(inode->i_sb))
- return 0;
- return posix_acl_chmod(inode, inode->i_mode);
- }
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