[net-next-2.6.git] / fs / reiserfs / xattr_acl.c

#include <linux/capability.h>
#include <linux/fs.h>
#include <linux/posix_acl.h>
#include <linux/reiserfs_fs.h>
#include <linux/errno.h>
#include <linux/pagemap.h>
#include <linux/xattr.h>
#include <linux/slab.h>
#include <linux/posix_acl_xattr.h>
#include <linux/reiserfs_xattr.h>
#include <linux/reiserfs_acl.h>
#include <asm/uaccess.h>

static int reiserfs_set_acl(struct reiserfs_transaction_handle *th,
			    struct inode *inode, int type,
			    struct posix_acl *acl);

static int
posix_acl_set(struct dentry *dentry, const char *name, const void *value,
		size_t size, int flags, int type)
{
	struct inode *inode = dentry->d_inode;
	struct posix_acl *acl;
	int error, error2;
	struct reiserfs_transaction_handle th;
	size_t jcreate_blocks;
	if (!reiserfs_posixacl(inode->i_sb))
		return -EOPNOTSUPP;
	if (!is_owner_or_cap(inode))
		return -EPERM;

	if (value) {
		acl = posix_acl_from_xattr(value, size);
		if (IS_ERR(acl)) {
			return PTR_ERR(acl);
		} else if (acl) {
			error = posix_acl_valid(acl);
			if (error)
				goto release_and_out;
		}
	} else
		acl = NULL;

	/* 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);
	if (error == 0) {
		error = reiserfs_set_acl(&th, inode, type, acl);
		error2 = journal_end(&th, inode->i_sb, jcreate_blocks);
		if (error2)
			error = error2;
	}
	reiserfs_write_unlock(inode->i_sb);

      release_and_out:
	posix_acl_release(acl);
	return error;
}

static int
posix_acl_get(struct dentry *dentry, const char *name, void *buffer,
		size_t size, int type)
{
	struct posix_acl *acl;
	int error;

	if (!reiserfs_posixacl(dentry->d_sb))
		return -EOPNOTSUPP;

	acl = reiserfs_get_acl(dentry->d_inode, type);
	if (IS_ERR(acl))
		return PTR_ERR(acl);
	if (acl == NULL)
		return -ENODATA;
	error = posix_acl_to_xattr(acl, buffer, size);
	posix_acl_release(acl);

	return error;
}

/*
 * Convert from filesystem to in-memory representation.
 */
static struct posix_acl *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);
			acl->a_entries[n].e_id = ACL_UNDEFINED_ID;
			break;

		case ACL_USER:
		case ACL_GROUP:
			value = (char *)value + sizeof(reiserfs_acl_entry);
			if ((char *)value > end)
				goto fail;
			acl->a_entries[n].e_id = 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 *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++) {
		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:
		case ACL_GROUP:
			entry->e_id = cpu_to_le32(acl->a_entries[n].e_id);
			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;

	acl = get_cached_acl(inode, type);
	if (acl != ACL_NOT_CACHED)
		return acl;

	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 = 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;

	if (S_ISLNK(inode->i_mode))
		return -EOPNOTSUPP;

	switch (type) {
	case ACL_TYPE_ACCESS:
		name = POSIX_ACL_XATTR_ACCESS;
		if (acl) {
			mode_t mode = inode->i_mode;
			error = posix_acl_equiv_mode(acl, &mode);
			if (error < 0)
				return error;
			else {
				inode->i_mode = mode;
				if (error == 0)
					acl = NULL;
			}
		}
		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 = 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 *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;
	}

	acl = reiserfs_get_acl(dir, ACL_TYPE_DEFAULT);
	if (IS_ERR(acl))
		return PTR_ERR(acl);

	if (acl) {
		struct posix_acl *acl_copy;
		mode_t mode = inode->i_mode;
		int need_acl;

		/* Copy the default ACL to the default ACL of a new directory */
		if (S_ISDIR(inode->i_mode)) {
			err = reiserfs_set_acl(th, inode, ACL_TYPE_DEFAULT,
					       acl);
			if (err)
				goto cleanup;
		}

		/* Now we reconcile the new ACL and the mode,
		   potentially modifying both */
		acl_copy = posix_acl_clone(acl, GFP_NOFS);
		if (!acl_copy) {
			err = -ENOMEM;
			goto cleanup;
		}

		need_acl = posix_acl_create_masq(acl_copy, &mode);
		if (need_acl >= 0) {
			if (mode != inode->i_mode) {
				inode->i_mode = mode;
			}

			/* If we need an ACL.. */
			if (need_acl > 0) {
				err = reiserfs_set_acl(th, inode,
						       ACL_TYPE_ACCESS,
						       acl_copy);
				if (err)
					goto cleanup_copy;
			}
		}
	      cleanup_copy:
		posix_acl_release(acl_copy);
	      cleanup:
		posix_acl_release(acl);
	} else {
	      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;
}

int reiserfs_acl_chmod(struct inode *inode)
{
	struct posix_acl *acl, *clone;
	int error;

	if (S_ISLNK(inode->i_mode))
		return -EOPNOTSUPP;

	if (get_inode_sd_version(inode) == STAT_DATA_V1 ||
	    !reiserfs_posixacl(inode->i_sb)) {
		return 0;
	}

	reiserfs_write_unlock(inode->i_sb);
	acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
	reiserfs_write_lock(inode->i_sb);
	if (!acl)
		return 0;
	if (IS_ERR(acl))
		return PTR_ERR(acl);
	clone = posix_acl_clone(acl, GFP_NOFS);
	posix_acl_release(acl);
	if (!clone)
		return -ENOMEM;
	error = posix_acl_chmod_masq(clone, inode->i_mode);
	if (!error) {
		struct reiserfs_transaction_handle th;
		size_t size = reiserfs_xattr_nblocks(inode,
					     reiserfs_acl_size(clone->a_count));
		reiserfs_write_lock(inode->i_sb);
		error = journal_begin(&th, inode->i_sb, size * 2);
		if (!error) {
			int error2;
			error = reiserfs_set_acl(&th, inode, ACL_TYPE_ACCESS,
						 clone);
			error2 = journal_end(&th, inode->i_sb, size * 2);
			if (error2)
				error = error2;
		}
		reiserfs_write_unlock(inode->i_sb);
	}
	posix_acl_release(clone);
	return error;
}

static size_t posix_acl_access_list(struct dentry *dentry, char *list,
				    size_t list_size, const char *name,
				    size_t name_len, int type)
{
	const size_t size = sizeof(POSIX_ACL_XATTR_ACCESS);
	if (!reiserfs_posixacl(dentry->d_sb))
		return 0;
	if (list && size <= list_size)
		memcpy(list, POSIX_ACL_XATTR_ACCESS, size);
	return size;
}

const struct xattr_handler reiserfs_posix_acl_access_handler = {
	.prefix = POSIX_ACL_XATTR_ACCESS,
	.flags = ACL_TYPE_ACCESS,
	.get = posix_acl_get,
	.set = posix_acl_set,
	.list = posix_acl_access_list,
};

static size_t posix_acl_default_list(struct dentry *dentry, char *list,
				     size_t list_size, const char *name,
				     size_t name_len, int type)
{
	const size_t size = sizeof(POSIX_ACL_XATTR_DEFAULT);
	if (!reiserfs_posixacl(dentry->d_sb))
		return 0;
	if (list && size <= list_size)
		memcpy(list, POSIX_ACL_XATTR_DEFAULT, size);
	return size;
}

const struct xattr_handler reiserfs_posix_acl_default_handler = {
	.prefix = POSIX_ACL_XATTR_DEFAULT,
	.flags = ACL_TYPE_DEFAULT,
	.get = posix_acl_get,
	.set = posix_acl_set,
	.list = posix_acl_default_list,
};
Commit	Line	Data
16f7e0fe	1	#include <linux/capability.h>
1da177e4 LT	2	#include <linux/fs.h>
	3	#include <linux/posix_acl.h>
	4	#include <linux/reiserfs_fs.h>
	5	#include <linux/errno.h>
	6	#include <linux/pagemap.h>
	7	#include <linux/xattr.h>
5a0e3ad6	8	#include <linux/slab.h>
9a59f452	9	#include <linux/posix_acl_xattr.h>
1da177e4 LT	10	#include <linux/reiserfs_xattr.h>
	11	#include <linux/reiserfs_acl.h>
	12	#include <asm/uaccess.h>
	13
0ab2621e JM	14	static int reiserfs_set_acl(struct reiserfs_transaction_handle *th,
0ab2621e JM	15	struct inode *inode, int type,
bd4c625c	16	struct posix_acl *acl);
1da177e4 LT	17
1da177e4 LT	18	static int
431547b3 CH	19	posix_acl_set(struct dentry dentry, const char name, const void *value,
431547b3 CH	20	size_t size, int flags, int type)
1da177e4	21	{
431547b3	22	struct inode *inode = dentry->d_inode;
1da177e4	23	struct posix_acl *acl;
0ab2621e JM	24	int error, error2;
	25	struct reiserfs_transaction_handle th;
	26	size_t jcreate_blocks;
1da177e4 LT	27	if (!reiserfs_posixacl(inode->i_sb))
1da177e4 LT	28	return -EOPNOTSUPP;
3bd858ab	29	if (!is_owner_or_cap(inode))
1da177e4 LT	30	return -EPERM;
	31
	32	if (value) {
	33	acl = posix_acl_from_xattr(value, size);
	34	if (IS_ERR(acl)) {
	35	return PTR_ERR(acl);
	36	} else if (acl) {
	37	error = posix_acl_valid(acl);
	38	if (error)
	39	goto release_and_out;
	40	}
	41	} else
	42	acl = NULL;
	43
0ab2621e JM	44	/* Pessimism: We can't assume that anything from the xattr root up
	45	* has been created. */
	46
	47	jcreate_blocks = reiserfs_xattr_jcreate_nblocks(inode) +
	48	reiserfs_xattr_nblocks(inode, size) * 2;
	49
	50	reiserfs_write_lock(inode->i_sb);
	51	error = journal_begin(&th, inode->i_sb, jcreate_blocks);
	52	if (error == 0) {
	53	error = reiserfs_set_acl(&th, inode, type, acl);
	54	error2 = journal_end(&th, inode->i_sb, jcreate_blocks);
	55	if (error2)
	56	error = error2;
	57	}
	58	reiserfs_write_unlock(inode->i_sb);
1da177e4	59
bd4c625c	60	release_and_out:
1da177e4 LT	61	posix_acl_release(acl);
	62	return error;
	63	}
	64
1da177e4	65	static int
431547b3 CH	66	posix_acl_get(struct dentry dentry, const char name, void *buffer,
431547b3 CH	67	size_t size, int type)
1da177e4 LT	68	{
	69	struct posix_acl *acl;
	70	int error;
	71
431547b3	72	if (!reiserfs_posixacl(dentry->d_sb))
1da177e4 LT	73	return -EOPNOTSUPP;
1da177e4 LT	74
431547b3	75	acl = reiserfs_get_acl(dentry->d_inode, type);
1da177e4 LT	76	if (IS_ERR(acl))
	77	return PTR_ERR(acl);
	78	if (acl == NULL)
	79	return -ENODATA;
	80	error = posix_acl_to_xattr(acl, buffer, size);
	81	posix_acl_release(acl);
	82
	83	return error;
	84	}
	85
1da177e4 LT	86	/*
	87	* Convert from filesystem to in-memory representation.
	88	*/
bd4c625c	89	static struct posix_acl posix_acl_from_disk(const void value, size_t size)
1da177e4 LT	90	{
	91	const char end = (char )value + size;
	92	int n, count;
	93	struct posix_acl *acl;
	94
	95	if (!value)
	96	return NULL;
	97	if (size < sizeof(reiserfs_acl_header))
bd4c625c LT	98	return ERR_PTR(-EINVAL);
bd4c625c LT	99	if (((reiserfs_acl_header *) value)->a_version !=
1da177e4 LT	100	cpu_to_le32(REISERFS_ACL_VERSION))
	101	return ERR_PTR(-EINVAL);
	102	value = (char *)value + sizeof(reiserfs_acl_header);
	103	count = reiserfs_acl_count(size);
	104	if (count < 0)
	105	return ERR_PTR(-EINVAL);
	106	if (count == 0)
	107	return NULL;
	108	acl = posix_acl_alloc(count, GFP_NOFS);
	109	if (!acl)
	110	return ERR_PTR(-ENOMEM);
bd4c625c LT	111	for (n = 0; n < count; n++) {
bd4c625c LT	112	reiserfs_acl_entry entry = (reiserfs_acl_entry ) value;
1da177e4 LT	113	if ((char *)value + sizeof(reiserfs_acl_entry_short) > end)
1da177e4 LT	114	goto fail;
bd4c625c	115	acl->a_entries[n].e_tag = le16_to_cpu(entry->e_tag);
1da177e4	116	acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm);
bd4c625c LT	117	switch (acl->a_entries[n].e_tag) {
	118	case ACL_USER_OBJ:
	119	case ACL_GROUP_OBJ:
	120	case ACL_MASK:
	121	case ACL_OTHER:
	122	value = (char *)value +
	123	sizeof(reiserfs_acl_entry_short);
	124	acl->a_entries[n].e_id = ACL_UNDEFINED_ID;
	125	break;
	126
	127	case ACL_USER:
	128	case ACL_GROUP:
	129	value = (char *)value + sizeof(reiserfs_acl_entry);
	130	if ((char *)value > end)
1da177e4	131	goto fail;
bd4c625c LT	132	acl->a_entries[n].e_id = le32_to_cpu(entry->e_id);
	133	break;
	134
	135	default:
	136	goto fail;
1da177e4 LT	137	}
	138	}
	139	if (value != end)
	140	goto fail;
	141	return acl;
	142
bd4c625c	143	fail:
1da177e4 LT	144	posix_acl_release(acl);
	145	return ERR_PTR(-EINVAL);
	146	}
	147
	148	/*
	149	* Convert from in-memory to filesystem representation.
	150	*/
bd4c625c	151	static void posix_acl_to_disk(const struct posix_acl acl, size_t * size)
1da177e4 LT	152	{
	153	reiserfs_acl_header *ext_acl;
	154	char *e;
	155	int n;
	156
	157	*size = reiserfs_acl_size(acl->a_count);
5cbded58	158	ext_acl = kmalloc(sizeof(reiserfs_acl_header) +
bd4c625c LT	159	acl->a_count *
	160	sizeof(reiserfs_acl_entry),
	161	GFP_NOFS);
1da177e4 LT	162	if (!ext_acl)
	163	return ERR_PTR(-ENOMEM);
	164	ext_acl->a_version = cpu_to_le32(REISERFS_ACL_VERSION);
	165	e = (char *)ext_acl + sizeof(reiserfs_acl_header);
bd4c625c LT	166	for (n = 0; n < acl->a_count; n++) {
	167	reiserfs_acl_entry entry = (reiserfs_acl_entry ) e;
	168	entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag);
1da177e4	169	entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
bd4c625c LT	170	switch (acl->a_entries[n].e_tag) {
	171	case ACL_USER:
	172	case ACL_GROUP:
	173	entry->e_id = cpu_to_le32(acl->a_entries[n].e_id);
	174	e += sizeof(reiserfs_acl_entry);
	175	break;
	176
	177	case ACL_USER_OBJ:
	178	case ACL_GROUP_OBJ:
	179	case ACL_MASK:
	180	case ACL_OTHER:
	181	e += sizeof(reiserfs_acl_entry_short);
	182	break;
	183
	184	default:
	185	goto fail;
1da177e4 LT	186	}
	187	}
	188	return (char *)ext_acl;
	189
bd4c625c	190	fail:
1da177e4 LT	191	kfree(ext_acl);
	192	return ERR_PTR(-EINVAL);
	193	}
	194
	195	/*
	196	* Inode operation get_posix_acl().
	197	*
1b1dcc1b	198	* inode->i_mutex: down
1da177e4 LT	199	* BKL held [before 2.5.x]
1da177e4 LT	200	*/
bd4c625c	201	struct posix_acl reiserfs_get_acl(struct inode inode, int type)
1da177e4 LT	202	{
1da177e4 LT	203	char name, value;
073aaa1b	204	struct posix_acl *acl;
3cdc409c	205	int size;
1da177e4	206	int retval;
bd4c625c	207
073aaa1b AV	208	acl = get_cached_acl(inode, type);
	209	if (acl != ACL_NOT_CACHED)
	210	return acl;
	211
bd4c625c LT	212	switch (type) {
	213	case ACL_TYPE_ACCESS:
	214	name = POSIX_ACL_XATTR_ACCESS;
bd4c625c LT	215	break;
	216	case ACL_TYPE_DEFAULT:
	217	name = POSIX_ACL_XATTR_DEFAULT;
bd4c625c LT	218	break;
bd4c625c LT	219	default:
073aaa1b	220	BUG();
bd4c625c LT	221	}
bd4c625c LT	222
bd4c625c	223	size = reiserfs_xattr_get(inode, name, NULL, 0);
3cdc409c	224	if (size < 0) {
bd4c625c	225	if (size == -ENODATA \|\| size == -ENOSYS) {
073aaa1b	226	set_cached_acl(inode, type, NULL);
bd4c625c LT	227	return NULL;
	228	}
	229	return ERR_PTR(size);
	230	}
1da177e4	231
bd4c625c LT	232	value = kmalloc(size, GFP_NOFS);
	233	if (!value)
	234	return ERR_PTR(-ENOMEM);
1da177e4 LT	235
	236	retval = reiserfs_xattr_get(inode, name, value, size);
	237	if (retval == -ENODATA \|\| retval == -ENOSYS) {
	238	/* This shouldn't actually happen as it should have
	239	been caught above.. but just in case */
	240	acl = NULL;
bd4c625c	241	} else if (retval < 0) {
1da177e4 LT	242	acl = ERR_PTR(retval);
	243	} else {
	244	acl = posix_acl_from_disk(value, retval);
bd4c625c	245	}
073aaa1b AV	246	if (!IS_ERR(acl))
073aaa1b AV	247	set_cached_acl(inode, type, acl);
1da177e4 LT	248
	249	kfree(value);
	250	return acl;
	251	}
	252
	253	/*
	254	* Inode operation set_posix_acl().
	255	*
1b1dcc1b	256	* inode->i_mutex: down
1da177e4 LT	257	* BKL held [before 2.5.x]
	258	*/
	259	static int
0ab2621e JM	260	reiserfs_set_acl(struct reiserfs_transaction_handle th, struct inode inode,
0ab2621e JM	261	int type, struct posix_acl *acl)
1da177e4	262	{
bd4c625c	263	char *name;
1da177e4	264	void *value = NULL;
48b32a35	265	size_t size = 0;
1da177e4	266	int error;
1da177e4 LT	267
	268	if (S_ISLNK(inode->i_mode))
	269	return -EOPNOTSUPP;
	270
bd4c625c LT	271	switch (type) {
	272	case ACL_TYPE_ACCESS:
	273	name = POSIX_ACL_XATTR_ACCESS;
bd4c625c LT	274	if (acl) {
	275	mode_t mode = inode->i_mode;
	276	error = posix_acl_equiv_mode(acl, &mode);
	277	if (error < 0)
	278	return error;
	279	else {
	280	inode->i_mode = mode;
	281	if (error == 0)
	282	acl = NULL;
	283	}
	284	}
	285	break;
	286	case ACL_TYPE_DEFAULT:
	287	name = POSIX_ACL_XATTR_DEFAULT;
bd4c625c LT	288	if (!S_ISDIR(inode->i_mode))
	289	return acl ? -EACCES : 0;
	290	break;
	291	default:
	292	return -EINVAL;
	293	}
	294
	295	if (acl) {
	296	value = posix_acl_to_disk(acl, &size);
	297	if (IS_ERR(value))
	298	return (int)PTR_ERR(value);
48b32a35 JM	299	}
48b32a35 JM	300
0ab2621e	301	error = reiserfs_xattr_set_handle(th, inode, name, value, size, 0);
48b32a35 JM	302
	303	/*
	304	* Ensure that the inode gets dirtied if we're only using
	305	* the mode bits and an old ACL didn't exist. We don't need
	306	* to check if the inode is hashed here since we won't get
	307	* called by reiserfs_inherit_default_acl().
	308	*/
	309	if (error == -ENODATA) {
	310	error = 0;
	311	if (type == ACL_TYPE_ACCESS) {
	312	inode->i_ctime = CURRENT_TIME_SEC;
bd4c625c	313	mark_inode_dirty(inode);
bd4c625c LT	314	}
bd4c625c LT	315	}
1da177e4	316
833d304b	317	kfree(value);
1da177e4	318
d984561b	319	if (!error)
073aaa1b	320	set_cached_acl(inode, type, acl);
1da177e4 LT	321
	322	return error;
	323	}
	324
1b1dcc1b	325	/* dir->i_mutex: locked,
1da177e4 LT	326	* inode is new and not released into the wild yet */
1da177e4 LT	327	int
0ab2621e JM	328	reiserfs_inherit_default_acl(struct reiserfs_transaction_handle *th,
0ab2621e JM	329	struct inode dir, struct dentry dentry,
bd4c625c	330	struct inode *inode)
1da177e4	331	{
bd4c625c LT	332	struct posix_acl *acl;
	333	int err = 0;
	334
	335	/* ACLs only get applied to files and directories */
	336	if (S_ISLNK(inode->i_mode))
	337	return 0;
	338
	339	/* ACLs can only be used on "new" objects, so if it's an old object
	340	* there is nothing to inherit from */
	341	if (get_inode_sd_version(dir) == STAT_DATA_V1)
	342	goto apply_umask;
	343
	344	/* Don't apply ACLs to objects in the .reiserfs_priv tree.. This
	345	* would be useless since permissions are ignored, and a pain because
	346	* it introduces locking cycles */
6dfede69 JM	347	if (IS_PRIVATE(dir)) {
6dfede69 JM	348	inode->i_flags \|= S_PRIVATE;
bd4c625c LT	349	goto apply_umask;
	350	}
	351
	352	acl = reiserfs_get_acl(dir, ACL_TYPE_DEFAULT);
7a77b15d	353	if (IS_ERR(acl))
bd4c625c	354	return PTR_ERR(acl);
bd4c625c LT	355
	356	if (acl) {
	357	struct posix_acl *acl_copy;
	358	mode_t mode = inode->i_mode;
	359	int need_acl;
	360
	361	/* Copy the default ACL to the default ACL of a new directory */
	362	if (S_ISDIR(inode->i_mode)) {
0ab2621e JM	363	err = reiserfs_set_acl(th, inode, ACL_TYPE_DEFAULT,
0ab2621e JM	364	acl);
bd4c625c LT	365	if (err)
	366	goto cleanup;
	367	}
	368
	369	/* Now we reconcile the new ACL and the mode,
	370	potentially modifying both */
	371	acl_copy = posix_acl_clone(acl, GFP_NOFS);
	372	if (!acl_copy) {
	373	err = -ENOMEM;
	374	goto cleanup;
	375	}
	376
	377	need_acl = posix_acl_create_masq(acl_copy, &mode);
	378	if (need_acl >= 0) {
	379	if (mode != inode->i_mode) {
	380	inode->i_mode = mode;
	381	}
	382
	383	/* If we need an ACL.. */
	384	if (need_acl > 0) {
0ab2621e JM	385	err = reiserfs_set_acl(th, inode,
	386	ACL_TYPE_ACCESS,
	387	acl_copy);
bd4c625c LT	388	if (err)
	389	goto cleanup_copy;
	390	}
	391	}
	392	cleanup_copy:
	393	posix_acl_release(acl_copy);
	394	cleanup:
	395	posix_acl_release(acl);
	396	} else {
	397	apply_umask:
	398	/* no ACL, apply umask */
ce3b0f8d	399	inode->i_mode &= ~current_umask();
bd4c625c LT	400	}
	401
	402	return err;
1da177e4 LT	403	}
1da177e4 LT	404
0ab2621e JM	405	/* This is used to cache the default acl before a new object is created.
	406	* The biggest reason for this is to get an idea of how many blocks will
	407	* actually be required for the create operation if we must inherit an ACL.
	408	* An ACL write can add up to 3 object creations and an additional file write
	409	* so we'd prefer not to reserve that many blocks in the journal if we can.
	410	* It also has the advantage of not loading the ACL with a transaction open,
	411	* this may seem silly, but if the owner of the directory is doing the
	412	* creation, the ACL may not be loaded since the permissions wouldn't require
	413	* it.
	414	* We return the number of blocks required for the transaction.
	415	*/
bd4c625c	416	int reiserfs_cache_default_acl(struct inode *inode)
1da177e4	417	{
0ab2621e JM	418	struct posix_acl *acl;
	419	int nblocks = 0;
	420
	421	if (IS_PRIVATE(inode))
	422	return 0;
	423
	424	acl = reiserfs_get_acl(inode, ACL_TYPE_DEFAULT);
	425
	426	if (acl && !IS_ERR(acl)) {
	427	int size = reiserfs_acl_size(acl->a_count);
	428
	429	/* Other xattrs can be created during inode creation. We don't
	430	* want to claim too many blocks, so we check to see if we
	431	* we need to create the tree to the xattrs, and then we
	432	* just want two files. */
	433	nblocks = reiserfs_xattr_jcreate_nblocks(inode);
	434	nblocks += JOURNAL_BLOCKS_PER_OBJECT(inode->i_sb);
	435
	436	REISERFS_I(inode)->i_flags \|= i_has_xattr_dir;
	437
	438	/* We need to account for writes + bitmaps for two files */
	439	nblocks += reiserfs_xattr_nblocks(inode, size) * 4;
	440	posix_acl_release(acl);
bd4c625c LT	441	}
bd4c625c LT	442
0ab2621e	443	return nblocks;
1da177e4 LT	444	}
1da177e4 LT	445
bd4c625c	446	int reiserfs_acl_chmod(struct inode *inode)
1da177e4	447	{
bd4c625c LT	448	struct posix_acl acl, clone;
bd4c625c LT	449	int error;
1da177e4	450
bd4c625c LT	451	if (S_ISLNK(inode->i_mode))
bd4c625c LT	452	return -EOPNOTSUPP;
1da177e4	453
bd4c625c LT	454	if (get_inode_sd_version(inode) == STAT_DATA_V1 \|\|
	455	!reiserfs_posixacl(inode->i_sb)) {
	456	return 0;
1da177e4 LT	457	}
1da177e4 LT	458
6c287054	459	reiserfs_write_unlock(inode->i_sb);
bd4c625c	460	acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
6c287054	461	reiserfs_write_lock(inode->i_sb);
bd4c625c LT	462	if (!acl)
	463	return 0;
	464	if (IS_ERR(acl))
	465	return PTR_ERR(acl);
	466	clone = posix_acl_clone(acl, GFP_NOFS);
	467	posix_acl_release(acl);
	468	if (!clone)
	469	return -ENOMEM;
	470	error = posix_acl_chmod_masq(clone, inode->i_mode);
0ab2621e JM	471	if (!error) {
	472	struct reiserfs_transaction_handle th;
	473	size_t size = reiserfs_xattr_nblocks(inode,
	474	reiserfs_acl_size(clone->a_count));
	475	reiserfs_write_lock(inode->i_sb);
	476	error = journal_begin(&th, inode->i_sb, size * 2);
	477	if (!error) {
	478	int error2;
	479	error = reiserfs_set_acl(&th, inode, ACL_TYPE_ACCESS,
	480	clone);
	481	error2 = journal_end(&th, inode->i_sb, size * 2);
	482	if (error2)
	483	error = error2;
	484	}
	485	reiserfs_write_unlock(inode->i_sb);
	486	}
bd4c625c LT	487	posix_acl_release(clone);
bd4c625c LT	488	return error;
1da177e4 LT	489	}
1da177e4 LT	490
431547b3	491	static size_t posix_acl_access_list(struct dentry dentry, char list,
48b32a35	492	size_t list_size, const char *name,
431547b3	493	size_t name_len, int type)
1da177e4	494	{
48b32a35	495	const size_t size = sizeof(POSIX_ACL_XATTR_ACCESS);
431547b3	496	if (!reiserfs_posixacl(dentry->d_sb))
bd4c625c	497	return 0;
48b32a35 JM	498	if (list && size <= list_size)
	499	memcpy(list, POSIX_ACL_XATTR_ACCESS, size);
	500	return size;
1da177e4 LT	501	}
1da177e4 LT	502
94d09a98	503	const struct xattr_handler reiserfs_posix_acl_access_handler = {
9a59f452	504	.prefix = POSIX_ACL_XATTR_ACCESS,
431547b3 CH	505	.flags = ACL_TYPE_ACCESS,
	506	.get = posix_acl_get,
	507	.set = posix_acl_set,
1da177e4 LT	508	.list = posix_acl_access_list,
	509	};
	510
431547b3	511	static size_t posix_acl_default_list(struct dentry dentry, char list,
48b32a35	512	size_t list_size, const char *name,
431547b3	513	size_t name_len, int type)
1da177e4	514	{
48b32a35	515	const size_t size = sizeof(POSIX_ACL_XATTR_DEFAULT);
431547b3	516	if (!reiserfs_posixacl(dentry->d_sb))
bd4c625c	517	return 0;
48b32a35 JM	518	if (list && size <= list_size)
	519	memcpy(list, POSIX_ACL_XATTR_DEFAULT, size);
	520	return size;
1da177e4 LT	521	}
1da177e4 LT	522
94d09a98	523	const struct xattr_handler reiserfs_posix_acl_default_handler = {
9a59f452	524	.prefix = POSIX_ACL_XATTR_DEFAULT,
431547b3 CH	525	.flags = ACL_TYPE_DEFAULT,
	526	.get = posix_acl_get,
	527	.set = posix_acl_set,
1da177e4 LT	528	.list = posix_acl_default_list,
1da177e4 LT	529	};