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/*

 * Virtio 9p system.posix* xattr callback

 *

 * Copyright IBM, Corp. 2010

 *

 * Authors:

 * Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

 *

 * This work is licensed under the terms of the GNU GPL, version 2.  See

 * the COPYING file in the top-level directory.

 *

 */

#include <sys/types.h>

#include "qemu/xattr.h"

#include "hw/virtio/virtio.h"

#include "virtio-9p.h"

#include "fsdev/file-op-9p.h"

#include "virtio-9p-xattr.h"

#define MAP_ACL_ACCESS "user.virtfs.system.posix_acl_access"

#define MAP_ACL_DEFAULT "user.virtfs.system.posix_acl_default"

#define ACL_ACCESS "system.posix_acl_access"

#define ACL_DEFAULT "system.posix_acl_default"

static ssize_t mp_pacl_getxattr(FsContext *ctx, const char *path,

                                const char *name, void *value, size_t size)

{

    char buffer[PATH_MAX];

    return lgetxattr(rpath(ctx, path, buffer), MAP_ACL_ACCESS, value, size);

}

static ssize_t mp_pacl_listxattr(FsContext *ctx, const char *path,

                                 char *name, void *value, size_t osize)

{

    ssize_t len = sizeof(ACL_ACCESS);

    if (!value) {

        return len;

    }

    if (osize < len) {

        errno = ERANGE;

        return -1;

    }

    /* len includes the trailing NUL */

    memcpy(value, ACL_ACCESS, len);

    return 0;

}

static int mp_pacl_setxattr(FsContext *ctx, const char *path, const char *name,

                            void *value, size_t size, int flags)

{

    char buffer[PATH_MAX];

    return lsetxattr(rpath(ctx, path, buffer), MAP_ACL_ACCESS, value,

            size, flags);

}

static int mp_pacl_removexattr(FsContext *ctx,

                               const char *path, const char *name)

{

    int ret;

    char buffer[PATH_MAX];

    ret  = lremovexattr(rpath(ctx, path, buffer), MAP_ACL_ACCESS);

    if (ret == -1 && errno == ENODATA) {

        /*

         * We don't get ENODATA error when trying to remove a

         * posix acl that is not present. So don't throw the error

         * even in case of mapped security model

         */

        errno = 0;

        ret = 0;

    }

    return ret;

}

static ssize_t mp_dacl_getxattr(FsContext *ctx, const char *path,

                                const char *name, void *value, size_t size)

{

    char buffer[PATH_MAX];

    return lgetxattr(rpath(ctx, path, buffer), MAP_ACL_DEFAULT, value, size);

}

static ssize_t mp_dacl_listxattr(FsContext *ctx, const char *path,

                                 char *name, void *value, size_t osize)

{

    ssize_t len = sizeof(ACL_DEFAULT);

    if (!value) {

        return len;

    }

    if (osize < len) {

        errno = ERANGE;

        return -1;

    }

    /* len includes the trailing NUL */

    memcpy(value, ACL_ACCESS, len);

    return 0;

}

static int mp_dacl_setxattr(FsContext *ctx, const char *path, const char *name,

                            void *value, size_t size, int flags)

{

    char buffer[PATH_MAX];

    return lsetxattr(rpath(ctx, path, buffer), MAP_ACL_DEFAULT, value,

            size, flags);

}

static int mp_dacl_removexattr(FsContext *ctx,

                               const char *path, const char *name)

{

    int ret;

    char buffer[PATH_MAX];

    ret  = lremovexattr(rpath(ctx, path, buffer), MAP_ACL_DEFAULT);

    if (ret == -1 && errno == ENODATA) {

        /*

         * We don't get ENODATA error when trying to remove a

         * posix acl that is not present. So don't throw the error

         * even in case of mapped security model

         */

        errno = 0;

        ret = 0;

    }

    return ret;

}

XattrOperations mapped_pacl_xattr = {

    .name = "system.posix_acl_access",

    .getxattr = mp_pacl_getxattr,

    .setxattr = mp_pacl_setxattr,

    .listxattr = mp_pacl_listxattr,

    .removexattr = mp_pacl_removexattr,

};

XattrOperations mapped_dacl_xattr = {

    .name = "system.posix_acl_default",

    .getxattr = mp_dacl_getxattr,

    .setxattr = mp_dacl_setxattr,

    .listxattr = mp_dacl_listxattr,

    .removexattr = mp_dacl_removexattr,

};

XattrOperations passthrough_acl_xattr = {

    .name = "system.posix_acl_",

    .getxattr = pt_getxattr,

    .setxattr = pt_setxattr,

    .listxattr = pt_listxattr,

    .removexattr = pt_removexattr,

};

XattrOperations none_acl_xattr = {

    .name = "system.posix_acl_",

    .getxattr = notsup_getxattr,

    .setxattr = notsup_setxattr,

    .listxattr = notsup_listxattr,

    .removexattr = notsup_removexattr,

};