[mirror_ubuntu-hirsute-kernel.git] / fs / fuse / xattr.c

/*
 * FUSE: Filesystem in Userspace
 * Copyright (C) 2001-2016  Miklos Szeredi <miklos@szeredi.hu>
 *
 * This program can be distributed under the terms of the GNU GPL.
 * See the file COPYING.
 */

#include "fuse_i.h"

#include <linux/xattr.h>
#include <linux/posix_acl_xattr.h>

int fuse_setxattr(struct inode *inode, const char *name, const void *value,
		  size_t size, int flags)
{
	struct fuse_mount *fm = get_fuse_mount(inode);
	FUSE_ARGS(args);
	struct fuse_setxattr_in inarg;
	int err;

	if (fm->fc->no_setxattr)
		return -EOPNOTSUPP;

	memset(&inarg, 0, sizeof(inarg));
	inarg.size = size;
	inarg.flags = flags;
	args.opcode = FUSE_SETXATTR;
	args.nodeid = get_node_id(inode);
	args.in_numargs = 3;
	args.in_args[0].size = sizeof(inarg);
	args.in_args[0].value = &inarg;
	args.in_args[1].size = strlen(name) + 1;
	args.in_args[1].value = name;
	args.in_args[2].size = size;
	args.in_args[2].value = value;
	err = fuse_simple_request(fm, &args);
	if (err == -ENOSYS) {
		fm->fc->no_setxattr = 1;
		err = -EOPNOTSUPP;
	}
	if (!err) {
		fuse_invalidate_attr(inode);
		fuse_update_ctime(inode);
	}
	return err;
}

ssize_t fuse_getxattr(struct inode *inode, const char *name, void *value,
		      size_t size)
{
	struct fuse_mount *fm = get_fuse_mount(inode);
	FUSE_ARGS(args);
	struct fuse_getxattr_in inarg;
	struct fuse_getxattr_out outarg;
	ssize_t ret;

	if (fm->fc->no_getxattr)
		return -EOPNOTSUPP;

	memset(&inarg, 0, sizeof(inarg));
	inarg.size = size;
	args.opcode = FUSE_GETXATTR;
	args.nodeid = get_node_id(inode);
	args.in_numargs = 2;
	args.in_args[0].size = sizeof(inarg);
	args.in_args[0].value = &inarg;
	args.in_args[1].size = strlen(name) + 1;
	args.in_args[1].value = name;
	/* This is really two different operations rolled into one */
	args.out_numargs = 1;
	if (size) {
		args.out_argvar = true;
		args.out_args[0].size = size;
		args.out_args[0].value = value;
	} else {
		args.out_args[0].size = sizeof(outarg);
		args.out_args[0].value = &outarg;
	}
	ret = fuse_simple_request(fm, &args);
	if (!ret && !size)
		ret = min_t(ssize_t, outarg.size, XATTR_SIZE_MAX);
	if (ret == -ENOSYS) {
		fm->fc->no_getxattr = 1;
		ret = -EOPNOTSUPP;
	}
	return ret;
}

static int fuse_verify_xattr_list(char *list, size_t size)
{
	size_t origsize = size;

	while (size) {
		size_t thislen = strnlen(list, size);

		if (!thislen || thislen == size)
			return -EIO;

		size -= thislen + 1;
		list += thislen + 1;
	}

	return origsize;
}

ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size)
{
	struct inode *inode = d_inode(entry);
	struct fuse_mount *fm = get_fuse_mount(inode);
	FUSE_ARGS(args);
	struct fuse_getxattr_in inarg;
	struct fuse_getxattr_out outarg;
	ssize_t ret;

	if (fuse_is_bad(inode))
		return -EIO;

	if (!fuse_allow_current_process(fm->fc))
		return -EACCES;

	if (fm->fc->no_listxattr)
		return -EOPNOTSUPP;

	memset(&inarg, 0, sizeof(inarg));
	inarg.size = size;
	args.opcode = FUSE_LISTXATTR;
	args.nodeid = get_node_id(inode);
	args.in_numargs = 1;
	args.in_args[0].size = sizeof(inarg);
	args.in_args[0].value = &inarg;
	/* This is really two different operations rolled into one */
	args.out_numargs = 1;
	if (size) {
		args.out_argvar = true;
		args.out_args[0].size = size;
		args.out_args[0].value = list;
	} else {
		args.out_args[0].size = sizeof(outarg);
		args.out_args[0].value = &outarg;
	}
	ret = fuse_simple_request(fm, &args);
	if (!ret && !size)
		ret = min_t(ssize_t, outarg.size, XATTR_LIST_MAX);
	if (ret > 0 && size)
		ret = fuse_verify_xattr_list(list, ret);
	if (ret == -ENOSYS) {
		fm->fc->no_listxattr = 1;
		ret = -EOPNOTSUPP;
	}
	return ret;
}

int fuse_removexattr(struct inode *inode, const char *name)
{
	struct fuse_mount *fm = get_fuse_mount(inode);
	FUSE_ARGS(args);
	int err;

	if (fm->fc->no_removexattr)
		return -EOPNOTSUPP;

	args.opcode = FUSE_REMOVEXATTR;
	args.nodeid = get_node_id(inode);
	args.in_numargs = 1;
	args.in_args[0].size = strlen(name) + 1;
	args.in_args[0].value = name;
	err = fuse_simple_request(fm, &args);
	if (err == -ENOSYS) {
		fm->fc->no_removexattr = 1;
		err = -EOPNOTSUPP;
	}
	if (!err) {
		fuse_invalidate_attr(inode);
		fuse_update_ctime(inode);
	}
	return err;
}

static int fuse_xattr_get(const struct xattr_handler *handler,
			 struct dentry *dentry, struct inode *inode,
			 const char *name, void *value, size_t size)
{
	if (fuse_is_bad(inode))
		return -EIO;

	return fuse_getxattr(inode, name, value, size);
}

static int fuse_xattr_set(const struct xattr_handler *handler,
			  struct dentry *dentry, struct inode *inode,
			  const char *name, const void *value, size_t size,
			  int flags)
{
	if (fuse_is_bad(inode))
		return -EIO;

	if (!value)
		return fuse_removexattr(inode, name);

	return fuse_setxattr(inode, name, value, size, flags);
}

static bool no_xattr_list(struct dentry *dentry)
{
	return false;
}

static int no_xattr_get(const struct xattr_handler *handler,
			struct dentry *dentry, struct inode *inode,
			const char *name, void *value, size_t size)
{
	return -EOPNOTSUPP;
}

static int no_xattr_set(const struct xattr_handler *handler,
			struct dentry *dentry, struct inode *nodee,
			const char *name, const void *value,
			size_t size, int flags)
{
	return -EOPNOTSUPP;
}

static const struct xattr_handler fuse_xattr_handler = {
	.prefix = "",
	.get    = fuse_xattr_get,
	.set    = fuse_xattr_set,
};

const struct xattr_handler *fuse_xattr_handlers[] = {
	&fuse_xattr_handler,
	NULL
};

const struct xattr_handler *fuse_acl_xattr_handlers[] = {
	&posix_acl_access_xattr_handler,
	&posix_acl_default_xattr_handler,
	&fuse_xattr_handler,
	NULL
};

static const struct xattr_handler fuse_no_acl_access_xattr_handler = {
	.name  = XATTR_NAME_POSIX_ACL_ACCESS,
	.flags = ACL_TYPE_ACCESS,
	.list  = no_xattr_list,
	.get   = no_xattr_get,
	.set   = no_xattr_set,
};

static const struct xattr_handler fuse_no_acl_default_xattr_handler = {
	.name  = XATTR_NAME_POSIX_ACL_DEFAULT,
	.flags = ACL_TYPE_ACCESS,
	.list  = no_xattr_list,
	.get   = no_xattr_get,
	.set   = no_xattr_set,
};

const struct xattr_handler *fuse_no_acl_xattr_handlers[] = {
	&fuse_no_acl_access_xattr_handler,
	&fuse_no_acl_default_xattr_handler,
	&fuse_xattr_handler,
	NULL
};
Commit	Line	Data
703c7362 SF	1	/*
	2	* FUSE: Filesystem in Userspace
	3	* Copyright (C) 2001-2016 Miklos Szeredi <miklos@szeredi.hu>
	4	*
	5	* This program can be distributed under the terms of the GNU GPL.
	6	* See the file COPYING.
	7	*/
	8
	9	#include "fuse_i.h"
	10
	11	#include <linux/xattr.h>
60bcc88a	12	#include <linux/posix_acl_xattr.h>
703c7362	13
60bcc88a SF	14	int fuse_setxattr(struct inode inode, const char name, const void *value,
60bcc88a SF	15	size_t size, int flags)
703c7362	16	{
fcee216b	17	struct fuse_mount *fm = get_fuse_mount(inode);
703c7362 SF	18	FUSE_ARGS(args);
	19	struct fuse_setxattr_in inarg;
	20	int err;
	21
fcee216b	22	if (fm->fc->no_setxattr)
703c7362 SF	23	return -EOPNOTSUPP;
	24
	25	memset(&inarg, 0, sizeof(inarg));
	26	inarg.size = size;
	27	inarg.flags = flags;
d5b48543 MS	28	args.opcode = FUSE_SETXATTR;
	29	args.nodeid = get_node_id(inode);
	30	args.in_numargs = 3;
	31	args.in_args[0].size = sizeof(inarg);
	32	args.in_args[0].value = &inarg;
	33	args.in_args[1].size = strlen(name) + 1;
	34	args.in_args[1].value = name;
	35	args.in_args[2].size = size;
	36	args.in_args[2].value = value;
fcee216b	37	err = fuse_simple_request(fm, &args);
703c7362	38	if (err == -ENOSYS) {
fcee216b	39	fm->fc->no_setxattr = 1;
703c7362 SF	40	err = -EOPNOTSUPP;
	41	}
	42	if (!err) {
	43	fuse_invalidate_attr(inode);
	44	fuse_update_ctime(inode);
	45	}
	46	return err;
	47	}
	48
60bcc88a SF	49	ssize_t fuse_getxattr(struct inode inode, const char name, void *value,
60bcc88a SF	50	size_t size)
703c7362	51	{
fcee216b	52	struct fuse_mount *fm = get_fuse_mount(inode);
703c7362 SF	53	FUSE_ARGS(args);
	54	struct fuse_getxattr_in inarg;
	55	struct fuse_getxattr_out outarg;
	56	ssize_t ret;
	57
fcee216b	58	if (fm->fc->no_getxattr)
703c7362 SF	59	return -EOPNOTSUPP;
	60
	61	memset(&inarg, 0, sizeof(inarg));
	62	inarg.size = size;
d5b48543 MS	63	args.opcode = FUSE_GETXATTR;
	64	args.nodeid = get_node_id(inode);
	65	args.in_numargs = 2;
	66	args.in_args[0].size = sizeof(inarg);
	67	args.in_args[0].value = &inarg;
	68	args.in_args[1].size = strlen(name) + 1;
	69	args.in_args[1].value = name;
703c7362	70	/* This is really two different operations rolled into one */
d5b48543	71	args.out_numargs = 1;
703c7362	72	if (size) {
1f4e9d03	73	args.out_argvar = true;
d5b48543 MS	74	args.out_args[0].size = size;
d5b48543 MS	75	args.out_args[0].value = value;
703c7362	76	} else {
d5b48543 MS	77	args.out_args[0].size = sizeof(outarg);
d5b48543 MS	78	args.out_args[0].value = &outarg;
703c7362	79	}
fcee216b	80	ret = fuse_simple_request(fm, &args);
703c7362	81	if (!ret && !size)
63401ccd	82	ret = min_t(ssize_t, outarg.size, XATTR_SIZE_MAX);
703c7362	83	if (ret == -ENOSYS) {
fcee216b	84	fm->fc->no_getxattr = 1;
703c7362 SF	85	ret = -EOPNOTSUPP;
	86	}
	87	return ret;
	88	}
	89
	90	static int fuse_verify_xattr_list(char *list, size_t size)
	91	{
	92	size_t origsize = size;
	93
	94	while (size) {
	95	size_t thislen = strnlen(list, size);
	96
	97	if (!thislen \|\| thislen == size)
	98	return -EIO;
	99
	100	size -= thislen + 1;
	101	list += thislen + 1;
	102	}
	103
	104	return origsize;
	105	}
	106
	107	ssize_t fuse_listxattr(struct dentry entry, char list, size_t size)
	108	{
	109	struct inode *inode = d_inode(entry);
fcee216b	110	struct fuse_mount *fm = get_fuse_mount(inode);
703c7362 SF	111	FUSE_ARGS(args);
	112	struct fuse_getxattr_in inarg;
	113	struct fuse_getxattr_out outarg;
	114	ssize_t ret;
	115
5d069dbe MS	116	if (fuse_is_bad(inode))
	117	return -EIO;
	118
fcee216b	119	if (!fuse_allow_current_process(fm->fc))
703c7362 SF	120	return -EACCES;
703c7362 SF	121
fcee216b	122	if (fm->fc->no_listxattr)
703c7362 SF	123	return -EOPNOTSUPP;
	124
	125	memset(&inarg, 0, sizeof(inarg));
	126	inarg.size = size;
d5b48543 MS	127	args.opcode = FUSE_LISTXATTR;
	128	args.nodeid = get_node_id(inode);
	129	args.in_numargs = 1;
	130	args.in_args[0].size = sizeof(inarg);
	131	args.in_args[0].value = &inarg;
703c7362	132	/* This is really two different operations rolled into one */
d5b48543	133	args.out_numargs = 1;
703c7362	134	if (size) {
1f4e9d03	135	args.out_argvar = true;
d5b48543 MS	136	args.out_args[0].size = size;
d5b48543 MS	137	args.out_args[0].value = list;
703c7362	138	} else {
d5b48543 MS	139	args.out_args[0].size = sizeof(outarg);
d5b48543 MS	140	args.out_args[0].value = &outarg;
703c7362	141	}
fcee216b	142	ret = fuse_simple_request(fm, &args);
703c7362	143	if (!ret && !size)
63401ccd	144	ret = min_t(ssize_t, outarg.size, XATTR_LIST_MAX);
703c7362 SF	145	if (ret > 0 && size)
	146	ret = fuse_verify_xattr_list(list, ret);
	147	if (ret == -ENOSYS) {
fcee216b	148	fm->fc->no_listxattr = 1;
703c7362 SF	149	ret = -EOPNOTSUPP;
	150	}
	151	return ret;
	152	}
	153
60bcc88a	154	int fuse_removexattr(struct inode inode, const char name)
703c7362	155	{
fcee216b	156	struct fuse_mount *fm = get_fuse_mount(inode);
703c7362 SF	157	FUSE_ARGS(args);
	158	int err;
	159
fcee216b	160	if (fm->fc->no_removexattr)
703c7362 SF	161	return -EOPNOTSUPP;
703c7362 SF	162
d5b48543 MS	163	args.opcode = FUSE_REMOVEXATTR;
	164	args.nodeid = get_node_id(inode);
	165	args.in_numargs = 1;
	166	args.in_args[0].size = strlen(name) + 1;
	167	args.in_args[0].value = name;
fcee216b	168	err = fuse_simple_request(fm, &args);
703c7362	169	if (err == -ENOSYS) {
fcee216b	170	fm->fc->no_removexattr = 1;
703c7362 SF	171	err = -EOPNOTSUPP;
	172	}
	173	if (!err) {
	174	fuse_invalidate_attr(inode);
	175	fuse_update_ctime(inode);
	176	}
	177	return err;
	178	}
	179
	180	static int fuse_xattr_get(const struct xattr_handler *handler,
	181	struct dentry dentry, struct inode inode,
	182	const char name, void value, size_t size)
	183	{
5d069dbe MS	184	if (fuse_is_bad(inode))
	185	return -EIO;
	186
703c7362 SF	187	return fuse_getxattr(inode, name, value, size);
	188	}
	189
	190	static int fuse_xattr_set(const struct xattr_handler *handler,
	191	struct dentry dentry, struct inode inode,
	192	const char name, const void value, size_t size,
	193	int flags)
	194	{
5d069dbe MS	195	if (fuse_is_bad(inode))
	196	return -EIO;
	197
703c7362 SF	198	if (!value)
	199	return fuse_removexattr(inode, name);
	200
	201	return fuse_setxattr(inode, name, value, size, flags);
	202	}
	203
e45b2546 EB	204	static bool no_xattr_list(struct dentry *dentry)
	205	{
	206	return false;
	207	}
	208
	209	static int no_xattr_get(const struct xattr_handler *handler,
	210	struct dentry dentry, struct inode inode,
	211	const char name, void value, size_t size)
	212	{
	213	return -EOPNOTSUPP;
	214	}
	215
	216	static int no_xattr_set(const struct xattr_handler *handler,
	217	struct dentry dentry, struct inode nodee,
	218	const char name, const void value,
	219	size_t size, int flags)
	220	{
	221	return -EOPNOTSUPP;
	222	}
	223
703c7362 SF	224	static const struct xattr_handler fuse_xattr_handler = {
	225	.prefix = "",
	226	.get = fuse_xattr_get,
	227	.set = fuse_xattr_set,
	228	};
	229
	230	const struct xattr_handler *fuse_xattr_handlers[] = {
	231	&fuse_xattr_handler,
	232	NULL
	233	};
60bcc88a SF	234
	235	const struct xattr_handler *fuse_acl_xattr_handlers[] = {
	236	&posix_acl_access_xattr_handler,
	237	&posix_acl_default_xattr_handler,
	238	&fuse_xattr_handler,
	239	NULL
	240	};
e45b2546 EB	241
	242	static const struct xattr_handler fuse_no_acl_access_xattr_handler = {
	243	.name = XATTR_NAME_POSIX_ACL_ACCESS,
	244	.flags = ACL_TYPE_ACCESS,
	245	.list = no_xattr_list,
	246	.get = no_xattr_get,
	247	.set = no_xattr_set,
	248	};
	249
	250	static const struct xattr_handler fuse_no_acl_default_xattr_handler = {
	251	.name = XATTR_NAME_POSIX_ACL_DEFAULT,
	252	.flags = ACL_TYPE_ACCESS,
	253	.list = no_xattr_list,
	254	.get = no_xattr_get,
	255	.set = no_xattr_set,
	256	};
	257
	258	const struct xattr_handler *fuse_no_acl_xattr_handlers[] = {
	259	&fuse_no_acl_access_xattr_handler,
	260	&fuse_no_acl_default_xattr_handler,
	261	&fuse_xattr_handler,
	262	NULL
	263	};