security/keys/compat.c

   1 /* 32-bit compatibility syscall for 64-bit systems
   2  *
   3  * Copyright (C) 2004-5 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12 #include <linux/syscalls.h>
  13 #include <linux/keyctl.h>
  14 #include <linux/compat.h>
  15 #include <linux/slab.h>
  16 #include "internal.h"
  17
  18 /*
  19  * Instantiate a key with the specified compatibility multipart payload and
  20  * link the key into the destination keyring if one is given.
  21  *
  22  * The caller must have the appropriate instantiation permit set for this to
  23  * work (see keyctl_assume_authority).  No other permissions are required.
  24  *
  25  * If successful, 0 will be returned.
  26  */
  27 static long compat_keyctl_instantiate_key_iov(
  28         key_serial_t id,
  29         const struct compat_iovec __user *_payload_iov,
  30         unsigned ioc,
  31         key_serial_t ringid)
  32 {
  33         struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
  34         struct iov_iter from;
  35         long ret;
  36
  37         if (!_payload_iov)
  38                 ioc = 0;
  39
  40         ret = compat_import_iovec(WRITE, _payload_iov, ioc,
  41                                   ARRAY_SIZE(iovstack), &iov,
  42                                   &from);
  43         if (ret < 0)
  44                 return ret;
  45
  46         ret = keyctl_instantiate_key_common(id, &from, ringid);
  47         kfree(iov);
  48         return ret;
  49 }
  50
  51 /*
  52  * The key control system call, 32-bit compatibility version for 64-bit archs
  53  *
  54  * This should only be called if the 64-bit arch uses weird pointers in 32-bit
  55  * mode or doesn't guarantee that the top 32-bits of the argument registers on
  56  * taking a 32-bit syscall are zero.  If you can, you should call sys_keyctl()
  57  * directly.
  58  */
  59 COMPAT_SYSCALL_DEFINE5(keyctl, u32, option,
  60                        u32, arg2, u32, arg3, u32, arg4, u32, arg5)
  61 {
  62         switch (option) {
  63         case KEYCTL_GET_KEYRING_ID:
  64                 return keyctl_get_keyring_ID(arg2, arg3);
  65
  66         case KEYCTL_JOIN_SESSION_KEYRING:
  67                 return keyctl_join_session_keyring(compat_ptr(arg2));
  68
  69         case KEYCTL_UPDATE:
  70                 return keyctl_update_key(arg2, compat_ptr(arg3), arg4);
  71
  72         case KEYCTL_REVOKE:
  73                 return keyctl_revoke_key(arg2);
  74
  75         case KEYCTL_DESCRIBE:
  76                 return keyctl_describe_key(arg2, compat_ptr(arg3), arg4);
  77
  78         case KEYCTL_CLEAR:
  79                 return keyctl_keyring_clear(arg2);
  80
  81         case KEYCTL_LINK:
  82                 return keyctl_keyring_link(arg2, arg3);
  83
  84         case KEYCTL_UNLINK:
  85                 return keyctl_keyring_unlink(arg2, arg3);
  86
  87         case KEYCTL_SEARCH:
  88                 return keyctl_keyring_search(arg2, compat_ptr(arg3),
  89                                              compat_ptr(arg4), arg5);
  90
  91         case KEYCTL_READ:
  92                 return keyctl_read_key(arg2, compat_ptr(arg3), arg4);
  93
  94         case KEYCTL_CHOWN:
  95                 return keyctl_chown_key(arg2, arg3, arg4);
  96
  97         case KEYCTL_SETPERM:
  98                 return keyctl_setperm_key(arg2, arg3);
  99
 100         case KEYCTL_INSTANTIATE:
 101                 return keyctl_instantiate_key(arg2, compat_ptr(arg3), arg4,
 102                                               arg5);
 103
 104         case KEYCTL_NEGATE:
 105                 return keyctl_negate_key(arg2, arg3, arg4);
 106
 107         case KEYCTL_SET_REQKEY_KEYRING:
 108                 return keyctl_set_reqkey_keyring(arg2);
 109
 110         case KEYCTL_SET_TIMEOUT:
 111                 return keyctl_set_timeout(arg2, arg3);
 112
 113         case KEYCTL_ASSUME_AUTHORITY:
 114                 return keyctl_assume_authority(arg2);
 115
 116         case KEYCTL_GET_SECURITY:
 117                 return keyctl_get_security(arg2, compat_ptr(arg3), arg4);
 118
 119         case KEYCTL_SESSION_TO_PARENT:
 120                 return keyctl_session_to_parent();
 121
 122         case KEYCTL_REJECT:
 123                 return keyctl_reject_key(arg2, arg3, arg4, arg5);
 124
 125         case KEYCTL_INSTANTIATE_IOV:
 126                 return compat_keyctl_instantiate_key_iov(
 127                         arg2, compat_ptr(arg3), arg4, arg5);
 128
 129         case KEYCTL_INVALIDATE:
 130                 return keyctl_invalidate_key(arg2);
 131
 132         case KEYCTL_GET_PERSISTENT:
 133                 return keyctl_get_persistent(arg2, arg3);
 134
 135         case KEYCTL_DH_COMPUTE:
 136                 return compat_keyctl_dh_compute(compat_ptr(arg2),
 137                                                 compat_ptr(arg3),
 138                                                 arg4, compat_ptr(arg5));
 139
 140         case KEYCTL_RESTRICT_KEYRING:
 141                 return keyctl_restrict_keyring(arg2, compat_ptr(arg3),
 142                                                compat_ptr(arg4));
 143
 144         default:
 145                 return -EOPNOTSUPP;
 146         }
 147 }