[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/posix_acl_xattr.h>
#include <linux/reiserfs_xattr.h>
#include <linux/reiserfs_acl.h>
#include <asm/uaccess.h>

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

static int
xattr_set_acl(struct inode *inode, int type, const void *value, size_t size)
{
	struct posix_acl *acl;
	int error;

	if (!reiserfs_posixacl(inode->i_sb))
		return -EOPNOTSUPP;
	if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
		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;

	error = reiserfs_set_acl(inode, type, acl);

      release_and_out:
	posix_acl_release(acl);
	return error;
}

static int
xattr_get_acl(struct inode *inode, int type, void *buffer, size_t size)
{
	struct posix_acl *acl;
	int error;

	if (!reiserfs_posixacl(inode->i_sb))
		return -EOPNOTSUPP;

	acl = reiserfs_get_acl(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 = (reiserfs_acl_header *) 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, **p_acl;
	int size;
	int retval;
	struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);

	switch (type) {
	case ACL_TYPE_ACCESS:
		name = POSIX_ACL_XATTR_ACCESS;
		p_acl = &reiserfs_i->i_acl_access;
		break;
	case ACL_TYPE_DEFAULT:
		name = POSIX_ACL_XATTR_DEFAULT;
		p_acl = &reiserfs_i->i_acl_default;
		break;
	default:
		return ERR_PTR(-EINVAL);
	}

	if (IS_ERR(*p_acl)) {
		if (PTR_ERR(*p_acl) == -ENODATA)
			return NULL;
	} else if (*p_acl != NULL)
		return posix_acl_dup(*p_acl);

	size = reiserfs_xattr_get(inode, name, NULL, 0);
	if (size < 0) {
		if (size == -ENODATA || size == -ENOSYS) {
			*p_acl = ERR_PTR(-ENODATA);
			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;
		*p_acl = ERR_PTR(-ENODATA);
	} else if (retval < 0) {
		acl = ERR_PTR(retval);
	} else {
		acl = posix_acl_from_disk(value, retval);
		if (!IS_ERR(acl))
			*p_acl = posix_acl_dup(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 inode *inode, int type, struct posix_acl *acl)
{
	char *name;
	void *value = NULL;
	struct posix_acl **p_acl;
	size_t size;
	int error;
	struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);

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

	switch (type) {
	case ACL_TYPE_ACCESS:
		name = POSIX_ACL_XATTR_ACCESS;
		p_acl = &reiserfs_i->i_acl_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;
		p_acl = &reiserfs_i->i_acl_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(inode, name, value, size, 0);
	} else {
		error = reiserfs_xattr_del(inode, name);
		if (error == -ENODATA) {
			/* This may seem odd here, but it means that the ACL was set
			 * with a value representable with mode bits. If there was
			 * an ACL before, reiserfs_xattr_del already dirtied the inode.
			 */
			mark_inode_dirty(inode);
			error = 0;
		}
	}

	kfree(value);

	if (!error) {
		/* Release the old one */
		if (!IS_ERR(*p_acl) && *p_acl)
			posix_acl_release(*p_acl);

		if (acl == NULL)
			*p_acl = ERR_PTR(-ENODATA);
		else
			*p_acl = posix_acl_dup(acl);
	}

	return error;
}

/* dir->i_mutex: locked,
 * inode is new and not released into the wild yet */
int
reiserfs_inherit_default_acl(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_reiserfs_priv_object(dir)) {
		reiserfs_mark_inode_private(inode);
		goto apply_umask;
	}

	acl = reiserfs_get_acl(dir, ACL_TYPE_DEFAULT);
	if (IS_ERR(acl)) {
		if (PTR_ERR(acl) == -ENODATA)
			goto apply_umask;
		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(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(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->fs->umask;
	}

	return err;
}

/* Looks up and caches the result of the default ACL.
 * We do this so that we don't need to carry the xattr_sem into
 * reiserfs_new_inode if we don't need to */
int reiserfs_cache_default_acl(struct inode *inode)
{
	int ret = 0;
	if (reiserfs_posixacl(inode->i_sb) && !is_reiserfs_priv_object(inode)) {
		struct posix_acl *acl;
		reiserfs_read_lock_xattr_i(inode);
		reiserfs_read_lock_xattrs(inode->i_sb);
		acl = reiserfs_get_acl(inode, ACL_TYPE_DEFAULT);
		reiserfs_read_unlock_xattrs(inode->i_sb);
		reiserfs_read_unlock_xattr_i(inode);
		ret = (acl && !IS_ERR(acl));
		if (ret)
			posix_acl_release(acl);
	}

	return ret;
}

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_read_lock_xattrs(inode->i_sb);
	acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
	reiserfs_read_unlock_xattrs(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) {
		int lock = !has_xattr_dir(inode);
		reiserfs_write_lock_xattr_i(inode);
		if (lock)
			reiserfs_write_lock_xattrs(inode->i_sb);
		else
			reiserfs_read_lock_xattrs(inode->i_sb);
		error = reiserfs_set_acl(inode, ACL_TYPE_ACCESS, clone);
		if (lock)
			reiserfs_write_unlock_xattrs(inode->i_sb);
		else
			reiserfs_read_unlock_xattrs(inode->i_sb);
		reiserfs_write_unlock_xattr_i(inode);
	}
	posix_acl_release(clone);
	return error;
}

static int
posix_acl_access_get(struct inode *inode, const char *name,
		     void *buffer, size_t size)
{
	if (strlen(name) != sizeof(POSIX_ACL_XATTR_ACCESS) - 1)
		return -EINVAL;
	return xattr_get_acl(inode, ACL_TYPE_ACCESS, buffer, size);
}

static int
posix_acl_access_set(struct inode *inode, const char *name,
		     const void *value, size_t size, int flags)
{
	if (strlen(name) != sizeof(POSIX_ACL_XATTR_ACCESS) - 1)
		return -EINVAL;
	return xattr_set_acl(inode, ACL_TYPE_ACCESS, value, size);
}

static int posix_acl_access_del(struct inode *inode, const char *name)
{
	struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
	struct posix_acl **acl = &reiserfs_i->i_acl_access;
	if (strlen(name) != sizeof(POSIX_ACL_XATTR_ACCESS) - 1)
		return -EINVAL;
	if (!IS_ERR(*acl) && *acl) {
		posix_acl_release(*acl);
		*acl = ERR_PTR(-ENODATA);
	}

	return 0;
}

static int
posix_acl_access_list(struct inode *inode, const char *name, int namelen,
		      char *out)
{
	int len = namelen;
	if (!reiserfs_posixacl(inode->i_sb))
		return 0;
	if (out)
		memcpy(out, name, len);

	return len;
}

struct reiserfs_xattr_handler posix_acl_access_handler = {
	.prefix = POSIX_ACL_XATTR_ACCESS,
	.get = posix_acl_access_get,
	.set = posix_acl_access_set,
	.del = posix_acl_access_del,
	.list = posix_acl_access_list,
};

static int
posix_acl_default_get(struct inode *inode, const char *name,
		      void *buffer, size_t size)
{
	if (strlen(name) != sizeof(POSIX_ACL_XATTR_DEFAULT) - 1)
		return -EINVAL;
	return xattr_get_acl(inode, ACL_TYPE_DEFAULT, buffer, size);
}

static int
posix_acl_default_set(struct inode *inode, const char *name,
		      const void *value, size_t size, int flags)
{
	if (strlen(name) != sizeof(POSIX_ACL_XATTR_DEFAULT) - 1)
		return -EINVAL;
	return xattr_set_acl(inode, ACL_TYPE_DEFAULT, value, size);
}

static int posix_acl_default_del(struct inode *inode, const char *name)
{
	struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
	struct posix_acl **acl = &reiserfs_i->i_acl_default;
	if (strlen(name) != sizeof(POSIX_ACL_XATTR_DEFAULT) - 1)
		return -EINVAL;
	if (!IS_ERR(*acl) && *acl) {
		posix_acl_release(*acl);
		*acl = ERR_PTR(-ENODATA);
	}

	return 0;
}

static int
posix_acl_default_list(struct inode *inode, const char *name, int namelen,
		       char *out)
{
	int len = namelen;
	if (!reiserfs_posixacl(inode->i_sb))
		return 0;
	if (out)
		memcpy(out, name, len);

	return len;
}

struct reiserfs_xattr_handler posix_acl_default_handler = {
	.prefix = POSIX_ACL_XATTR_DEFAULT,
	.get = posix_acl_default_get,
	.set = posix_acl_default_set,
	.del = posix_acl_default_del,
	.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>
9a59f452	8	#include <linux/posix_acl_xattr.h>
1da177e4 LT	9	#include <linux/reiserfs_xattr.h>
	10	#include <linux/reiserfs_acl.h>
	11	#include <asm/uaccess.h>
	12
bd4c625c LT	13	static int reiserfs_set_acl(struct inode *inode, int type,
bd4c625c LT	14	struct posix_acl *acl);
1da177e4 LT	15
	16	static int
	17	xattr_set_acl(struct inode inode, int type, const void value, size_t size)
	18	{
	19	struct posix_acl *acl;
	20	int error;
	21
	22	if (!reiserfs_posixacl(inode->i_sb))
	23	return -EOPNOTSUPP;
	24	if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
	25	return -EPERM;
	26
	27	if (value) {
	28	acl = posix_acl_from_xattr(value, size);
	29	if (IS_ERR(acl)) {
	30	return PTR_ERR(acl);
	31	} else if (acl) {
	32	error = posix_acl_valid(acl);
	33	if (error)
	34	goto release_and_out;
	35	}
	36	} else
	37	acl = NULL;
	38
bd4c625c	39	error = reiserfs_set_acl(inode, type, acl);
1da177e4	40
bd4c625c	41	release_and_out:
1da177e4 LT	42	posix_acl_release(acl);
	43	return error;
	44	}
	45
1da177e4 LT	46	static int
	47	xattr_get_acl(struct inode inode, int type, void buffer, size_t size)
	48	{
	49	struct posix_acl *acl;
	50	int error;
	51
	52	if (!reiserfs_posixacl(inode->i_sb))
	53	return -EOPNOTSUPP;
	54
bd4c625c	55	acl = reiserfs_get_acl(inode, type);
1da177e4 LT	56	if (IS_ERR(acl))
	57	return PTR_ERR(acl);
	58	if (acl == NULL)
	59	return -ENODATA;
	60	error = posix_acl_to_xattr(acl, buffer, size);
	61	posix_acl_release(acl);
	62
	63	return error;
	64	}
	65
1da177e4 LT	66	/*
	67	* Convert from filesystem to in-memory representation.
	68	*/
bd4c625c	69	static struct posix_acl posix_acl_from_disk(const void value, size_t size)
1da177e4 LT	70	{
	71	const char end = (char )value + size;
	72	int n, count;
	73	struct posix_acl *acl;
	74
	75	if (!value)
	76	return NULL;
	77	if (size < sizeof(reiserfs_acl_header))
bd4c625c LT	78	return ERR_PTR(-EINVAL);
bd4c625c LT	79	if (((reiserfs_acl_header *) value)->a_version !=
1da177e4 LT	80	cpu_to_le32(REISERFS_ACL_VERSION))
	81	return ERR_PTR(-EINVAL);
	82	value = (char *)value + sizeof(reiserfs_acl_header);
	83	count = reiserfs_acl_count(size);
	84	if (count < 0)
	85	return ERR_PTR(-EINVAL);
	86	if (count == 0)
	87	return NULL;
	88	acl = posix_acl_alloc(count, GFP_NOFS);
	89	if (!acl)
	90	return ERR_PTR(-ENOMEM);
bd4c625c LT	91	for (n = 0; n < count; n++) {
bd4c625c LT	92	reiserfs_acl_entry entry = (reiserfs_acl_entry ) value;
1da177e4 LT	93	if ((char *)value + sizeof(reiserfs_acl_entry_short) > end)
1da177e4 LT	94	goto fail;
bd4c625c	95	acl->a_entries[n].e_tag = le16_to_cpu(entry->e_tag);
1da177e4	96	acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm);
bd4c625c LT	97	switch (acl->a_entries[n].e_tag) {
	98	case ACL_USER_OBJ:
	99	case ACL_GROUP_OBJ:
	100	case ACL_MASK:
	101	case ACL_OTHER:
	102	value = (char *)value +
	103	sizeof(reiserfs_acl_entry_short);
	104	acl->a_entries[n].e_id = ACL_UNDEFINED_ID;
	105	break;
	106
	107	case ACL_USER:
	108	case ACL_GROUP:
	109	value = (char *)value + sizeof(reiserfs_acl_entry);
	110	if ((char *)value > end)
1da177e4	111	goto fail;
bd4c625c LT	112	acl->a_entries[n].e_id = le32_to_cpu(entry->e_id);
	113	break;
	114
	115	default:
	116	goto fail;
1da177e4 LT	117	}
	118	}
	119	if (value != end)
	120	goto fail;
	121	return acl;
	122
bd4c625c	123	fail:
1da177e4 LT	124	posix_acl_release(acl);
	125	return ERR_PTR(-EINVAL);
	126	}
	127
	128	/*
	129	* Convert from in-memory to filesystem representation.
	130	*/
bd4c625c	131	static void posix_acl_to_disk(const struct posix_acl acl, size_t * size)
1da177e4 LT	132	{
	133	reiserfs_acl_header *ext_acl;
	134	char *e;
	135	int n;
	136
	137	*size = reiserfs_acl_size(acl->a_count);
bd4c625c LT	138	ext_acl = (reiserfs_acl_header *) kmalloc(sizeof(reiserfs_acl_header) +
	139	acl->a_count *
	140	sizeof(reiserfs_acl_entry),
	141	GFP_NOFS);
1da177e4 LT	142	if (!ext_acl)
	143	return ERR_PTR(-ENOMEM);
	144	ext_acl->a_version = cpu_to_le32(REISERFS_ACL_VERSION);
	145	e = (char *)ext_acl + sizeof(reiserfs_acl_header);
bd4c625c LT	146	for (n = 0; n < acl->a_count; n++) {
	147	reiserfs_acl_entry entry = (reiserfs_acl_entry ) e;
	148	entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag);
1da177e4	149	entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
bd4c625c LT	150	switch (acl->a_entries[n].e_tag) {
	151	case ACL_USER:
	152	case ACL_GROUP:
	153	entry->e_id = cpu_to_le32(acl->a_entries[n].e_id);
	154	e += sizeof(reiserfs_acl_entry);
	155	break;
	156
	157	case ACL_USER_OBJ:
	158	case ACL_GROUP_OBJ:
	159	case ACL_MASK:
	160	case ACL_OTHER:
	161	e += sizeof(reiserfs_acl_entry_short);
	162	break;
	163
	164	default:
	165	goto fail;
1da177e4 LT	166	}
	167	}
	168	return (char *)ext_acl;
	169
bd4c625c	170	fail:
1da177e4 LT	171	kfree(ext_acl);
	172	return ERR_PTR(-EINVAL);
	173	}
	174
	175	/*
	176	* Inode operation get_posix_acl().
	177	*
1b1dcc1b	178	* inode->i_mutex: down
1da177e4 LT	179	* BKL held [before 2.5.x]
1da177e4 LT	180	*/
bd4c625c	181	struct posix_acl reiserfs_get_acl(struct inode inode, int type)
1da177e4 LT	182	{
	183	char name, value;
	184	struct posix_acl acl, *p_acl;
3cdc409c	185	int size;
1da177e4	186	int retval;
bd4c625c LT	187	struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
	188
	189	switch (type) {
	190	case ACL_TYPE_ACCESS:
	191	name = POSIX_ACL_XATTR_ACCESS;
	192	p_acl = &reiserfs_i->i_acl_access;
	193	break;
	194	case ACL_TYPE_DEFAULT:
	195	name = POSIX_ACL_XATTR_DEFAULT;
	196	p_acl = &reiserfs_i->i_acl_default;
	197	break;
	198	default:
	199	return ERR_PTR(-EINVAL);
	200	}
	201
	202	if (IS_ERR(*p_acl)) {
	203	if (PTR_ERR(*p_acl) == -ENODATA)
	204	return NULL;
	205	} else if (*p_acl != NULL)
	206	return posix_acl_dup(*p_acl);
	207
	208	size = reiserfs_xattr_get(inode, name, NULL, 0);
3cdc409c	209	if (size < 0) {
bd4c625c LT	210	if (size == -ENODATA \|\| size == -ENOSYS) {
	211	*p_acl = ERR_PTR(-ENODATA);
	212	return NULL;
	213	}
	214	return ERR_PTR(size);
	215	}
1da177e4	216
bd4c625c LT	217	value = kmalloc(size, GFP_NOFS);
	218	if (!value)
	219	return ERR_PTR(-ENOMEM);
1da177e4 LT	220
	221	retval = reiserfs_xattr_get(inode, name, value, size);
	222	if (retval == -ENODATA \|\| retval == -ENOSYS) {
	223	/* This shouldn't actually happen as it should have
	224	been caught above.. but just in case */
	225	acl = NULL;
bd4c625c LT	226	*p_acl = ERR_PTR(-ENODATA);
bd4c625c LT	227	} else if (retval < 0) {
1da177e4 LT	228	acl = ERR_PTR(retval);
	229	} else {
	230	acl = posix_acl_from_disk(value, retval);
90947ef2 JM	231	if (!IS_ERR(acl))
90947ef2 JM	232	*p_acl = posix_acl_dup(acl);
bd4c625c	233	}
1da177e4 LT	234
	235	kfree(value);
	236	return acl;
	237	}
	238
	239	/*
	240	* Inode operation set_posix_acl().
	241	*
1b1dcc1b	242	* inode->i_mutex: down
1da177e4 LT	243	* BKL held [before 2.5.x]
	244	*/
	245	static int
	246	reiserfs_set_acl(struct inode inode, int type, struct posix_acl acl)
	247	{
bd4c625c	248	char *name;
1da177e4 LT	249	void *value = NULL;
	250	struct posix_acl **p_acl;
	251	size_t size;
	252	int error;
bd4c625c	253	struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
1da177e4 LT	254
	255	if (S_ISLNK(inode->i_mode))
	256	return -EOPNOTSUPP;
	257
bd4c625c LT	258	switch (type) {
	259	case ACL_TYPE_ACCESS:
	260	name = POSIX_ACL_XATTR_ACCESS;
	261	p_acl = &reiserfs_i->i_acl_access;
	262	if (acl) {
	263	mode_t mode = inode->i_mode;
	264	error = posix_acl_equiv_mode(acl, &mode);
	265	if (error < 0)
	266	return error;
	267	else {
	268	inode->i_mode = mode;
	269	if (error == 0)
	270	acl = NULL;
	271	}
	272	}
	273	break;
	274	case ACL_TYPE_DEFAULT:
	275	name = POSIX_ACL_XATTR_DEFAULT;
	276	p_acl = &reiserfs_i->i_acl_default;
	277	if (!S_ISDIR(inode->i_mode))
	278	return acl ? -EACCES : 0;
	279	break;
	280	default:
	281	return -EINVAL;
	282	}
	283
	284	if (acl) {
	285	value = posix_acl_to_disk(acl, &size);
	286	if (IS_ERR(value))
	287	return (int)PTR_ERR(value);
	288	error = reiserfs_xattr_set(inode, name, value, size, 0);
1da177e4	289	} else {
bd4c625c LT	290	error = reiserfs_xattr_del(inode, name);
	291	if (error == -ENODATA) {
	292	/* This may seem odd here, but it means that the ACL was set
	293	* with a value representable with mode bits. If there was
	294	* an ACL before, reiserfs_xattr_del already dirtied the inode.
	295	*/
	296	mark_inode_dirty(inode);
	297	error = 0;
	298	}
	299	}
1da177e4	300
833d304b	301	kfree(value);
1da177e4	302
bd4c625c LT	303	if (!error) {
	304	/* Release the old one */
	305	if (!IS_ERR(p_acl) && p_acl)
	306	posix_acl_release(*p_acl);
1da177e4	307
bd4c625c LT	308	if (acl == NULL)
	309	*p_acl = ERR_PTR(-ENODATA);
	310	else
	311	*p_acl = posix_acl_dup(acl);
	312	}
1da177e4 LT	313
	314	return error;
	315	}
	316
1b1dcc1b	317	/* dir->i_mutex: locked,
1da177e4 LT	318	* inode is new and not released into the wild yet */
1da177e4 LT	319	int
bd4c625c LT	320	reiserfs_inherit_default_acl(struct inode dir, struct dentry dentry,
bd4c625c LT	321	struct inode *inode)
1da177e4	322	{
bd4c625c LT	323	struct posix_acl *acl;
	324	int err = 0;
	325
	326	/* ACLs only get applied to files and directories */
	327	if (S_ISLNK(inode->i_mode))
	328	return 0;
	329
	330	/* ACLs can only be used on "new" objects, so if it's an old object
	331	* there is nothing to inherit from */
	332	if (get_inode_sd_version(dir) == STAT_DATA_V1)
	333	goto apply_umask;
	334
	335	/* Don't apply ACLs to objects in the .reiserfs_priv tree.. This
	336	* would be useless since permissions are ignored, and a pain because
	337	* it introduces locking cycles */
	338	if (is_reiserfs_priv_object(dir)) {
	339	reiserfs_mark_inode_private(inode);
	340	goto apply_umask;
	341	}
	342
	343	acl = reiserfs_get_acl(dir, ACL_TYPE_DEFAULT);
	344	if (IS_ERR(acl)) {
	345	if (PTR_ERR(acl) == -ENODATA)
	346	goto apply_umask;
	347	return PTR_ERR(acl);
	348	}
	349
	350	if (acl) {
	351	struct posix_acl *acl_copy;
	352	mode_t mode = inode->i_mode;
	353	int need_acl;
	354
	355	/* Copy the default ACL to the default ACL of a new directory */
	356	if (S_ISDIR(inode->i_mode)) {
	357	err = reiserfs_set_acl(inode, ACL_TYPE_DEFAULT, acl);
	358	if (err)
	359	goto cleanup;
	360	}
	361
	362	/* Now we reconcile the new ACL and the mode,
	363	potentially modifying both */
	364	acl_copy = posix_acl_clone(acl, GFP_NOFS);
	365	if (!acl_copy) {
	366	err = -ENOMEM;
	367	goto cleanup;
	368	}
	369
	370	need_acl = posix_acl_create_masq(acl_copy, &mode);
	371	if (need_acl >= 0) {
	372	if (mode != inode->i_mode) {
	373	inode->i_mode = mode;
	374	}
	375
	376	/* If we need an ACL.. */
	377	if (need_acl > 0) {
	378	err =
	379	reiserfs_set_acl(inode, ACL_TYPE_ACCESS,
	380	acl_copy);
	381	if (err)
	382	goto cleanup_copy;
	383	}
	384	}
	385	cleanup_copy:
	386	posix_acl_release(acl_copy);
387	cleanup:
388	posix_acl_release(acl);
389	} else {
390	apply_umask:
391	/* no ACL, apply umask */
392	inode->i_mode &= ~current->fs->umask;
393	}
394
395	return err;
1da177e4 LT	396	}
	397
	398	/* Looks up and caches the result of the default ACL.
	399	* We do this so that we don't need to carry the xattr_sem into
	400	* reiserfs_new_inode if we don't need to */
bd4c625c	401	int reiserfs_cache_default_acl(struct inode *inode)
1da177e4	402	{
bd4c625c LT	403	int ret = 0;
	404	if (reiserfs_posixacl(inode->i_sb) && !is_reiserfs_priv_object(inode)) {
	405	struct posix_acl *acl;
	406	reiserfs_read_lock_xattr_i(inode);
	407	reiserfs_read_lock_xattrs(inode->i_sb);
	408	acl = reiserfs_get_acl(inode, ACL_TYPE_DEFAULT);
	409	reiserfs_read_unlock_xattrs(inode->i_sb);
	410	reiserfs_read_unlock_xattr_i(inode);
b9251b82 JK	411	ret = (acl && !IS_ERR(acl));
	412	if (ret)
	413	posix_acl_release(acl);
bd4c625c LT	414	}
	415
	416	return ret;
1da177e4 LT	417	}
1da177e4 LT	418
bd4c625c	419	int reiserfs_acl_chmod(struct inode *inode)
1da177e4	420	{
bd4c625c LT	421	struct posix_acl acl, clone;
bd4c625c LT	422	int error;
1da177e4	423
bd4c625c LT	424	if (S_ISLNK(inode->i_mode))
bd4c625c LT	425	return -EOPNOTSUPP;
1da177e4	426
bd4c625c LT	427	if (get_inode_sd_version(inode) == STAT_DATA_V1 \|\|
	428	!reiserfs_posixacl(inode->i_sb)) {
	429	return 0;
1da177e4 LT	430	}
1da177e4 LT	431
bd4c625c LT	432	reiserfs_read_lock_xattrs(inode->i_sb);
	433	acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
	434	reiserfs_read_unlock_xattrs(inode->i_sb);
	435	if (!acl)
	436	return 0;
	437	if (IS_ERR(acl))
	438	return PTR_ERR(acl);
	439	clone = posix_acl_clone(acl, GFP_NOFS);
	440	posix_acl_release(acl);
	441	if (!clone)
	442	return -ENOMEM;
	443	error = posix_acl_chmod_masq(clone, inode->i_mode);
	444	if (!error) {
	445	int lock = !has_xattr_dir(inode);
	446	reiserfs_write_lock_xattr_i(inode);
	447	if (lock)
	448	reiserfs_write_lock_xattrs(inode->i_sb);
	449	else
	450	reiserfs_read_lock_xattrs(inode->i_sb);
	451	error = reiserfs_set_acl(inode, ACL_TYPE_ACCESS, clone);
	452	if (lock)
	453	reiserfs_write_unlock_xattrs(inode->i_sb);
	454	else
	455	reiserfs_read_unlock_xattrs(inode->i_sb);
	456	reiserfs_write_unlock_xattr_i(inode);
	457	}
	458	posix_acl_release(clone);
	459	return error;
1da177e4 LT	460	}
	461
	462	static int
	463	posix_acl_access_get(struct inode inode, const char name,
bd4c625c	464	void *buffer, size_t size)
1da177e4	465	{
bd4c625c	466	if (strlen(name) != sizeof(POSIX_ACL_XATTR_ACCESS) - 1)
1da177e4 LT	467	return -EINVAL;
	468	return xattr_get_acl(inode, ACL_TYPE_ACCESS, buffer, size);
	469	}
	470
	471	static int
	472	posix_acl_access_set(struct inode inode, const char name,
bd4c625c	473	const void *value, size_t size, int flags)
1da177e4	474	{
bd4c625c	475	if (strlen(name) != sizeof(POSIX_ACL_XATTR_ACCESS) - 1)
1da177e4 LT	476	return -EINVAL;
	477	return xattr_set_acl(inode, ACL_TYPE_ACCESS, value, size);
	478	}
	479
bd4c625c	480	static int posix_acl_access_del(struct inode inode, const char name)
1da177e4	481	{
bd4c625c LT	482	struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
	483	struct posix_acl **acl = &reiserfs_i->i_acl_access;
	484	if (strlen(name) != sizeof(POSIX_ACL_XATTR_ACCESS) - 1)
	485	return -EINVAL;
	486	if (!IS_ERR(acl) && acl) {
	487	posix_acl_release(*acl);
	488	*acl = ERR_PTR(-ENODATA);
	489	}
	490
	491	return 0;
1da177e4 LT	492	}
	493
	494	static int
bd4c625c LT	495	posix_acl_access_list(struct inode inode, const char name, int namelen,
bd4c625c LT	496	char *out)
1da177e4	497	{
bd4c625c LT	498	int len = namelen;
	499	if (!reiserfs_posixacl(inode->i_sb))
	500	return 0;
	501	if (out)
	502	memcpy(out, name, len);
1da177e4	503
bd4c625c	504	return len;
1da177e4 LT	505	}
	506
	507	struct reiserfs_xattr_handler posix_acl_access_handler = {
9a59f452	508	.prefix = POSIX_ACL_XATTR_ACCESS,
1da177e4 LT	509	.get = posix_acl_access_get,
	510	.set = posix_acl_access_set,
	511	.del = posix_acl_access_del,
	512	.list = posix_acl_access_list,
	513	};
	514
	515	static int
bd4c625c LT	516	posix_acl_default_get(struct inode inode, const char name,
bd4c625c LT	517	void *buffer, size_t size)
1da177e4	518	{
bd4c625c	519	if (strlen(name) != sizeof(POSIX_ACL_XATTR_DEFAULT) - 1)
1da177e4 LT	520	return -EINVAL;
	521	return xattr_get_acl(inode, ACL_TYPE_DEFAULT, buffer, size);
	522	}
	523
	524	static int
	525	posix_acl_default_set(struct inode inode, const char name,
bd4c625c	526	const void *value, size_t size, int flags)
1da177e4	527	{
bd4c625c	528	if (strlen(name) != sizeof(POSIX_ACL_XATTR_DEFAULT) - 1)
1da177e4 LT	529	return -EINVAL;
	530	return xattr_set_acl(inode, ACL_TYPE_DEFAULT, value, size);
	531	}
	532
bd4c625c	533	static int posix_acl_default_del(struct inode inode, const char name)
1da177e4	534	{
bd4c625c LT	535	struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
	536	struct posix_acl **acl = &reiserfs_i->i_acl_default;
	537	if (strlen(name) != sizeof(POSIX_ACL_XATTR_DEFAULT) - 1)
	538	return -EINVAL;
	539	if (!IS_ERR(acl) && acl) {
	540	posix_acl_release(*acl);
	541	*acl = ERR_PTR(-ENODATA);
	542	}
	543
	544	return 0;
1da177e4 LT	545	}
	546
	547	static int
bd4c625c LT	548	posix_acl_default_list(struct inode inode, const char name, int namelen,
bd4c625c LT	549	char *out)
1da177e4	550	{
bd4c625c LT	551	int len = namelen;
	552	if (!reiserfs_posixacl(inode->i_sb))
	553	return 0;
	554	if (out)
	555	memcpy(out, name, len);
1da177e4	556
bd4c625c	557	return len;
1da177e4 LT	558	}
	559
	560	struct reiserfs_xattr_handler posix_acl_default_handler = {
9a59f452	561	.prefix = POSIX_ACL_XATTR_DEFAULT,
1da177e4 LT	562	.get = posix_acl_default_get,
	563	.set = posix_acl_default_set,
	564	.del = posix_acl_default_del,
	565	.list = posix_acl_default_list,
	566	};