LXR qemu/hw/9pfs/virtio-9p-xattr-user.c

   1/*
   2 * Virtio 9p user. 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 "hw/virtio/virtio.h"
  16#include "virtio-9p.h"
  17#include "fsdev/file-op-9p.h"
  18#include "virtio-9p-xattr.h"
  19
  20
  21static ssize_t mp_user_getxattr(FsContext *ctx, const char *path,
  22                                const char *name, void *value, size_t size)
  23{
  24    char buffer[PATH_MAX];
  25    if (strncmp(name, "user.virtfs.", 12) == 0) {
  26        /*
  27         * Don't allow fetch of user.virtfs namesapce
  28         * in case of mapped security
  29         */
  30        errno = ENOATTR;
  31        return -1;
  32    }
  33    return lgetxattr(rpath(ctx, path, buffer), name, value, size);
  34}
  35
  36static ssize_t mp_user_listxattr(FsContext *ctx, const char *path,
  37                                 char *name, void *value, size_t size)
  38{
  39    int name_size = strlen(name) + 1;
  40    if (strncmp(name, "user.virtfs.", 12) == 0) {
  41
  42        /*  check if it is a mapped posix acl */
  43        if (strncmp(name, "user.virtfs.system.posix_acl_", 29) == 0) {
  44            /* adjust the name and size */
  45            name += 12;
  46            name_size -= 12;
  47        } else {
  48            /*
  49             * Don't allow fetch of user.virtfs namesapce
  50             * in case of mapped security
  51             */
  52            return 0;
  53        }
  54    }
  55    if (!value) {
  56        return name_size;
  57    }
  58
  59    if (size < name_size) {
  60        errno = ERANGE;
  61        return -1;
  62    }
  63
  64    /* name_size includes the trailing NUL. */
  65    memcpy(value, name, name_size);
  66    return name_size;
  67}
  68
  69static int mp_user_setxattr(FsContext *ctx, const char *path, const char *name,
  70                            void *value, size_t size, int flags)
  71{
  72    char buffer[PATH_MAX];
  73    if (strncmp(name, "user.virtfs.", 12) == 0) {
  74        /*
  75         * Don't allow fetch of user.virtfs namesapce
  76         * in case of mapped security
  77         */
  78        errno = EACCES;
  79        return -1;
  80    }
  81    return lsetxattr(rpath(ctx, path, buffer), name, value, size, flags);
  82}
  83
  84static int mp_user_removexattr(FsContext *ctx,
  85                               const char *path, const char *name)
  86{
  87    char buffer[PATH_MAX];
  88    if (strncmp(name, "user.virtfs.", 12) == 0) {
  89        /*
  90         * Don't allow fetch of user.virtfs namesapce
  91         * in case of mapped security
  92         */
  93        errno = EACCES;
  94        return -1;
  95    }
  96    return lremovexattr(rpath(ctx, path, buffer), name);
  97}
  98
  99XattrOperations mapped_user_xattr = {
 100    .name = "user.",
 101    .getxattr = mp_user_getxattr,
 102    .setxattr = mp_user_setxattr,
 103    .listxattr = mp_user_listxattr,
 104    .removexattr = mp_user_removexattr,
 105};
 106
 107XattrOperations passthrough_user_xattr = {
 108    .name = "user.",
 109    .getxattr = pt_getxattr,
 110    .setxattr = pt_setxattr,
 111    .listxattr = pt_listxattr,
 112    .removexattr = pt_removexattr,
 113};
 114