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mirror of https://git.FreeBSD.org/src.git synced 2024-11-28 08:02:54 +00:00

linux(4): Implement xattr syscalls

Reviewed by:
Differential revision:	https://reviews.freebsd.org/D35544
MFC after:		1 month
This commit is contained in:
Dmitry Chagin 2023-07-22 14:03:33 +03:00
parent 6453d4240f
commit 22dca7acf7
4 changed files with 401 additions and 21 deletions

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@ -146,24 +146,3 @@ DUMMY(pidfd_send_signal);
DUMMY(io_uring_setup);
DUMMY(io_uring_enter);
DUMMY(io_uring_register);
#define DUMMY_XATTR(s) \
int \
linux_ ## s ## xattr( \
struct thread *td, struct linux_ ## s ## xattr_args *arg) \
{ \
\
return (EOPNOTSUPP); \
}
DUMMY_XATTR(set);
DUMMY_XATTR(lset);
DUMMY_XATTR(fset);
DUMMY_XATTR(get);
DUMMY_XATTR(lget);
DUMMY_XATTR(fget);
DUMMY_XATTR(list);
DUMMY_XATTR(llist);
DUMMY_XATTR(flist);
DUMMY_XATTR(remove);
DUMMY_XATTR(lremove);
DUMMY_XATTR(fremove);

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@ -0,0 +1,399 @@
/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2023 Dmitry Chagin <dchagin@FreeBSD.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/extattr.h>
#include <sys/fcntl.h>
#include <sys/namei.h>
#include <sys/proc.h>
#include <sys/syscallsubr.h>
#ifdef COMPAT_LINUX32
#include <machine/../linux32/linux.h>
#include <machine/../linux32/linux32_proto.h>
#else
#include <machine/../linux/linux.h>
#include <machine/../linux/linux_proto.h>
#endif
#include <compat/linux/linux_util.h>
#define LINUX_XATTR_SIZE_MAX 65536
#define LINUX_XATTR_LIST_MAX 65536
#define LINUX_XATTR_NAME_MAX 255
#define LINUX_XATTR_CREATE 0x1
#define LINUX_XATTR_REPLACE 0x2
#define LINUX_XATTR_FLAGS LINUX_XATTR_CREATE|LINUX_XATTR_REPLACE
struct listxattr_args {
int fd;
const char *path;
char *list;
l_size_t size;
int follow;
};
struct setxattr_args {
int fd;
const char *path;
const char *name;
void *value;
l_size_t size;
l_int flags;
int follow;
};
static char *extattr_namespace_names[] = EXTATTR_NAMESPACE_NAMES;
static int
xatrr_to_extattr(const char *uattrname, int *attrnamespace, char *attrname)
{
char uname[LINUX_XATTR_NAME_MAX + 1], *dot;
size_t len, cplen;
int error;
error = copyinstr(uattrname, uname, sizeof(uname), &cplen);
if (error != 0)
return (error);
if (cplen == sizeof(uname))
return (ERANGE);
dot = strchr(uname, '.');
if (dot == NULL)
return (ENOTSUP);
*dot = '\0';
for (*attrnamespace = EXTATTR_NAMESPACE_USER;
*attrnamespace < nitems(extattr_namespace_names);
(*attrnamespace)++) {
if (bcmp(uname, extattr_namespace_names[*attrnamespace],
dot - uname + 1) == 0) {
dot++;
len = strlen(dot) + 1;
bcopy(dot, attrname, len);
return (0);
}
}
return (ENOTSUP);
}
static int
listxattr(struct thread *td, struct listxattr_args *args)
{
char attrname[LINUX_XATTR_NAME_MAX + 1];
char *data, *prefix, *key;
struct uio auio;
struct iovec aiov;
unsigned char keylen;
size_t sz, cnt, rs, prefixlen, pairlen;
int attrnamespace, error;
if (args->size != 0)
sz = min(LINUX_XATTR_LIST_MAX, args->size);
else
sz = LINUX_XATTR_LIST_MAX;
data = malloc(sz, M_LINUX, M_WAITOK);
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_rw = UIO_READ;
auio.uio_segflg = UIO_SYSSPACE;
auio.uio_td = td;
cnt = 0;
for (attrnamespace = EXTATTR_NAMESPACE_USER;
attrnamespace < nitems(extattr_namespace_names);
attrnamespace++) {
aiov.iov_base = data;
aiov.iov_len = sz;
auio.uio_resid = sz;
auio.uio_offset = 0;
if (args->path != NULL)
error = kern_extattr_list_path(td, args->path,
attrnamespace, &auio, args->follow, UIO_USERSPACE);
else
error = kern_extattr_list_fd(td, args->fd,
attrnamespace, &auio);
rs = sz - auio.uio_resid;
if (error != 0 || rs == 0)
continue;
prefix = extattr_namespace_names[attrnamespace];
prefixlen = strlen(prefix);
key = data;
while (rs > 0) {
keylen = (unsigned char)key[0];
pairlen = prefixlen + 1 + keylen + 1;
if (cnt + pairlen > LINUX_XATTR_LIST_MAX) {
error = E2BIG;
break;
}
if ((args->list != NULL && cnt > args->size) ||
pairlen >= sizeof(attrname)) {
error = ERANGE;
break;
}
++key;
if (args->list != NULL) {
sprintf(attrname, "%s.%.*s", prefix, keylen, key);
error = copyout(attrname, args->list, pairlen);
if (error != 0)
break;
args->list += pairlen;
}
cnt += pairlen;
key += keylen;
rs -= (keylen + 1);
}
}
if (error == 0)
td->td_retval[0] = cnt;
free(data, M_LINUX);
return (error);
}
int
linux_listxattr(struct thread *td, struct linux_listxattr_args *args)
{
struct listxattr_args eargs = {
.fd = -1,
.path = args->path,
.list = args->list,
.size = args->size,
.follow = FOLLOW,
};
return (listxattr(td, &eargs));
}
int
linux_llistxattr(struct thread *td, struct linux_llistxattr_args *args)
{
struct listxattr_args eargs = {
.fd = -1,
.path = args->path,
.list = args->list,
.size = args->size,
.follow = NOFOLLOW,
};
return (listxattr(td, &eargs));
}
int
linux_flistxattr(struct thread *td, struct linux_flistxattr_args *args)
{
struct listxattr_args eargs = {
.fd = args->fd,
.path = NULL,
.list = args->list,
.size = args->size,
.follow = 0,
};
return (listxattr(td, &eargs));
}
static int
linux_path_removexattr(struct thread *td, const char *upath, const char *uname,
int follow)
{
char attrname[LINUX_XATTR_NAME_MAX + 1];
int attrnamespace, error;
error = xatrr_to_extattr(uname, &attrnamespace, attrname);
if (error != 0)
return (error);
return (kern_extattr_delete_path(td, upath, attrnamespace,
attrname, follow, UIO_USERSPACE));
}
int
linux_removexattr(struct thread *td, struct linux_removexattr_args *args)
{
return (linux_path_removexattr(td, args->path, args->name,
FOLLOW));
}
int
linux_lremovexattr(struct thread *td, struct linux_lremovexattr_args *args)
{
return (linux_path_removexattr(td, args->path, args->name,
NOFOLLOW));
}
int
linux_fremovexattr(struct thread *td, struct linux_fremovexattr_args *args)
{
char attrname[LINUX_XATTR_NAME_MAX + 1];
int attrnamespace, error;
error = xatrr_to_extattr(args->name, &attrnamespace, attrname);
if (error != 0)
return (error);
return (kern_extattr_delete_fd(td, args->fd, attrnamespace,
attrname));
}
static int
linux_path_getxattr(struct thread *td, const char *upath, const char *uname,
void *value, l_size_t size, int follow)
{
char attrname[LINUX_XATTR_NAME_MAX + 1];
int attrnamespace, error;
error = xatrr_to_extattr(uname, &attrnamespace, attrname);
if (error != 0)
return (error);
return (kern_extattr_get_path(td, upath, attrnamespace,
attrname, value, size, follow, UIO_USERSPACE));
}
int
linux_getxattr(struct thread *td, struct linux_getxattr_args *args)
{
return (linux_path_getxattr(td, args->path, args->name,
args->value, args->size, FOLLOW));
}
int
linux_lgetxattr(struct thread *td, struct linux_lgetxattr_args *args)
{
return (linux_path_getxattr(td, args->path, args->name,
args->value, args->size, NOFOLLOW));
}
int
linux_fgetxattr(struct thread *td, struct linux_fgetxattr_args *args)
{
char attrname[LINUX_XATTR_NAME_MAX + 1];
int attrnamespace, error;
error = xatrr_to_extattr(args->name, &attrnamespace, attrname);
if (error != 0)
return (error);
return (kern_extattr_get_fd(td, args->fd, attrnamespace,
attrname, args->value, args->size));
}
static int
setxattr(struct thread *td, struct setxattr_args *args)
{
char attrname[LINUX_XATTR_NAME_MAX + 1];
int attrnamespace, error;
if ((args->flags & ~(LINUX_XATTR_FLAGS)) != 0 ||
args->flags == (LINUX_XATTR_FLAGS))
return (EINVAL);
error = xatrr_to_extattr(args->name, &attrnamespace, attrname);
if (error != 0)
return (error);
if ((args->flags & (LINUX_XATTR_FLAGS)) != 0 ) {
if (args->path != NULL)
error = kern_extattr_get_path(td, args->path,
attrnamespace, attrname, NULL, args->size,
args->follow, UIO_USERSPACE);
else
error = kern_extattr_get_fd(td, args->fd,
attrnamespace, attrname, NULL, args->size);
if ((args->flags & LINUX_XATTR_CREATE) != 0) {
if (error == 0)
error = EEXIST;
else if (error == ENOATTR)
error = 0;
}
if (error != 0)
goto out;
}
if (args->path != NULL)
error = kern_extattr_set_path(td, args->path, attrnamespace,
attrname, args->value, args->size, args->follow,
UIO_USERSPACE);
else
error = kern_extattr_set_fd(td, args->fd, attrnamespace,
attrname, args->value, args->size);
out:
td->td_retval[0] = 0;
return (error);
}
int
linux_setxattr(struct thread *td, struct linux_setxattr_args *args)
{
struct setxattr_args eargs = {
.fd = -1,
.path = args->path,
.name = args->name,
.value = args->value,
.size = args->size,
.flags = args->flags,
.follow = FOLLOW,
};
return (setxattr(td, &eargs));
}
int
linux_lsetxattr(struct thread *td, struct linux_lsetxattr_args *args)
{
struct setxattr_args eargs = {
.fd = -1,
.path = args->path,
.name = args->name,
.value = args->value,
.size = args->size,
.flags = args->flags,
.follow = NOFOLLOW,
};
return (setxattr(td, &eargs));
}
int
linux_fsetxattr(struct thread *td, struct linux_fsetxattr_args *args)
{
struct setxattr_args eargs = {
.fd = args->fd,
.path = NULL,
.name = args->name,
.value = args->value,
.size = args->size,
.flags = args->flags,
.follow = 0,
};
return (setxattr(td, &eargs));
}

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@ -34,6 +34,7 @@ SRCS= linux${SFX}_dummy_machdep.c \
linux_timer.c \
linux_uid16.c \
linux_vdso.c \
linux_xattr.c \
opt_inet6.h \
opt_ktrace.h \
opt_posix.h \

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@ -29,6 +29,7 @@ SRCS= linux_dummy_machdep.c \
linux_time.c \
linux_vdso.c \
linux_timer.c \
linux_xattr.c \
opt_ktrace.h \
opt_inet6.h \
opt_posix.h \