LXR qemu/hw/9pfs/virtio-9p-posix-acl.c

   1/*
   2 * Virtio 9p system.posix* xattr callback
   3 *
   4 * Copyright IBM, Corp. 2010
   5 *
   6 * Authors:
   7 * Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
   8 *
   9 * This work is licensed under the terms of the GNU GPL, version 2.  See
  10 * the COPYING file in the top-level directory.
  11 *
  12 */
  13
  14#include <sys/types.h>
  15#include "qemu/xattr.h"
  16#include "hw/virtio/virtio.h"
  17#include "virtio-9p.h"
  18#include "fsdev/file-op-9p.h"
  19#include "virtio-9p-xattr.h"
  20
  21#define MAP_ACL_ACCESS "user.virtfs.system.posix_acl_access"
  22#define MAP_ACL_DEFAULT "user.virtfs.system.posix_acl_default"
  23#define ACL_ACCESS "system.posix_acl_access"
  24#define ACL_DEFAULT "system.posix_acl_default"
  25
  26static ssize_t mp_pacl_getxattr(FsContext *ctx, const char *path,
  27                                const char *name, void *value, size_t size)
  28{
  29    char buffer[PATH_MAX];
  30    return lgetxattr(rpath(ctx, path, buffer), MAP_ACL_ACCESS, value, size);
  31}
  32
  33static ssize_t mp_pacl_listxattr(FsContext *ctx, const char *path,
  34                                 char *name, void *value, size_t osize)
  35{
  36    ssize_t len = sizeof(ACL_ACCESS);
  37
  38    if (!value) {
  39        return len;
  40    }
  41
  42    if (osize < len) {
  43        errno = ERANGE;
  44        return -1;
  45    }
  46
  47    /* len includes the trailing NUL */
  48    memcpy(value, ACL_ACCESS, len);
  49    return 0;
  50}
  51
  52static int mp_pacl_setxattr(FsContext *ctx, const char *path, const char *name,
  53                            void *value, size_t size, int flags)
  54{
  55    char buffer[PATH_MAX];
  56    return lsetxattr(rpath(ctx, path, buffer), MAP_ACL_ACCESS, value,
  57            size, flags);
  58}
  59
  60static int mp_pacl_removexattr(FsContext *ctx,
  61                               const char *path, const char *name)
  62{
  63    int ret;
  64    char buffer[PATH_MAX];
  65    ret  = lremovexattr(rpath(ctx, path, buffer), MAP_ACL_ACCESS);
  66    if (ret == -1 && errno == ENODATA) {
  67        /*
  68         * We don't get ENODATA error when trying to remove a
  69         * posix acl that is not present. So don't throw the error
  70         * even in case of mapped security model
  71         */
  72        errno = 0;
  73        ret = 0;
  74    }
  75    return ret;
  76}
  77
  78static ssize_t mp_dacl_getxattr(FsContext *ctx, const char *path,
  79                                const char *name, void *value, size_t size)
  80{
  81    char buffer[PATH_MAX];
  82    return lgetxattr(rpath(ctx, path, buffer), MAP_ACL_DEFAULT, value, size);
  83}
  84
  85static ssize_t mp_dacl_listxattr(FsContext *ctx, const char *path,
  86                                 char *name, void *value, size_t osize)
  87{
  88    ssize_t len = sizeof(ACL_DEFAULT);
  89
  90    if (!value) {
  91        return len;
  92    }
  93
  94    if (osize < len) {
  95        errno = ERANGE;
  96        return -1;
  97    }
  98
  99    /* len includes the trailing NUL */
 100    memcpy(value, ACL_ACCESS, len);
 101    return 0;
 102}
 103
 104static int mp_dacl_setxattr(FsContext *ctx, const char *path, const char *name,
 105                            void *value, size_t size, int flags)
 106{
 107    char buffer[PATH_MAX];
 108    return lsetxattr(rpath(ctx, path, buffer), MAP_ACL_DEFAULT, value,
 109            size, flags);
 110}
 111
 112static int mp_dacl_removexattr(FsContext *ctx,
 113                               const char *path, const char *name)
 114{
 115    int ret;
 116    char buffer[PATH_MAX];
 117    ret  = lremovexattr(rpath(ctx, path, buffer), MAP_ACL_DEFAULT);
 118    if (ret == -1 && errno == ENODATA) {
 119        /*
 120         * We don't get ENODATA error when trying to remove a
 121         * posix acl that is not present. So don't throw the error
 122         * even in case of mapped security model
 123         */
 124        errno = 0;
 125        ret = 0;
 126    }
 127    return ret;
 128}
 129
 130
 131XattrOperations mapped_pacl_xattr = {
 132    .name = "system.posix_acl_access",
 133    .getxattr = mp_pacl_getxattr,
 134    .setxattr = mp_pacl_setxattr,
 135    .listxattr = mp_pacl_listxattr,
 136    .removexattr = mp_pacl_removexattr,
 137};
 138
 139XattrOperations mapped_dacl_xattr = {
 140    .name = "system.posix_acl_default",
 141    .getxattr = mp_dacl_getxattr,
 142    .setxattr = mp_dacl_setxattr,
 143    .listxattr = mp_dacl_listxattr,
 144    .removexattr = mp_dacl_removexattr,
 145};
 146
 147XattrOperations passthrough_acl_xattr = {
 148    .name = "system.posix_acl_",
 149    .getxattr = pt_getxattr,
 150    .setxattr = pt_setxattr,
 151    .listxattr = pt_listxattr,
 152    .removexattr = pt_removexattr,
 153};
 154
 155XattrOperations none_acl_xattr = {
 156    .name = "system.posix_acl_",
 157    .getxattr = notsup_getxattr,
 158    .setxattr = notsup_setxattr,
 159    .listxattr = notsup_listxattr,
 160    .removexattr = notsup_removexattr,
 161};
 162