Linux Kernel  3.7.1
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compat.c
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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 ([email protected])
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  long ret;
35 
36  if (!_payload_iov || !ioc)
37  goto no_payload;
38 
39  ret = compat_rw_copy_check_uvector(WRITE, _payload_iov, ioc,
40  ARRAY_SIZE(iovstack),
41  iovstack, &iov);
42  if (ret < 0)
43  return ret;
44  if (ret == 0)
45  goto no_payload_free;
46 
47  ret = keyctl_instantiate_key_common(id, iov, ioc, ret, ringid);
48 
49  if (iov != iovstack)
50  kfree(iov);
51  return ret;
52 
53 no_payload_free:
54  if (iov != iovstack)
55  kfree(iov);
56 no_payload:
57  return keyctl_instantiate_key_common(id, NULL, 0, 0, ringid);
58 }
59 
60 /*
61  * The key control system call, 32-bit compatibility version for 64-bit archs
62  *
63  * This should only be called if the 64-bit arch uses weird pointers in 32-bit
64  * mode or doesn't guarantee that the top 32-bits of the argument registers on
65  * taking a 32-bit syscall are zero. If you can, you should call sys_keyctl()
66  * directly.
67  */
70 {
71  switch (option) {
73  return keyctl_get_keyring_ID(arg2, arg3);
74 
76  return keyctl_join_session_keyring(compat_ptr(arg2));
77 
78  case KEYCTL_UPDATE:
79  return keyctl_update_key(arg2, compat_ptr(arg3), arg4);
80 
81  case KEYCTL_REVOKE:
82  return keyctl_revoke_key(arg2);
83 
84  case KEYCTL_DESCRIBE:
85  return keyctl_describe_key(arg2, compat_ptr(arg3), arg4);
86 
87  case KEYCTL_CLEAR:
88  return keyctl_keyring_clear(arg2);
89 
90  case KEYCTL_LINK:
91  return keyctl_keyring_link(arg2, arg3);
92 
93  case KEYCTL_UNLINK:
94  return keyctl_keyring_unlink(arg2, arg3);
95 
96  case KEYCTL_SEARCH:
97  return keyctl_keyring_search(arg2, compat_ptr(arg3),
98  compat_ptr(arg4), arg5);
99 
100  case KEYCTL_READ:
101  return keyctl_read_key(arg2, compat_ptr(arg3), arg4);
102 
103  case KEYCTL_CHOWN:
104  return keyctl_chown_key(arg2, arg3, arg4);
105 
106  case KEYCTL_SETPERM:
107  return keyctl_setperm_key(arg2, arg3);
108 
109  case KEYCTL_INSTANTIATE:
110  return keyctl_instantiate_key(arg2, compat_ptr(arg3), arg4,
111  arg5);
112 
113  case KEYCTL_NEGATE:
114  return keyctl_negate_key(arg2, arg3, arg4);
115 
117  return keyctl_set_reqkey_keyring(arg2);
118 
119  case KEYCTL_SET_TIMEOUT:
120  return keyctl_set_timeout(arg2, arg3);
121 
123  return keyctl_assume_authority(arg2);
124 
125  case KEYCTL_GET_SECURITY:
126  return keyctl_get_security(arg2, compat_ptr(arg3), arg4);
127 
129  return keyctl_session_to_parent();
130 
131  case KEYCTL_REJECT:
132  return keyctl_reject_key(arg2, arg3, arg4, arg5);
133 
135  return compat_keyctl_instantiate_key_iov(
136  arg2, compat_ptr(arg3), arg4, arg5);
137 
138  case KEYCTL_INVALIDATE:
139  return keyctl_invalidate_key(arg2);
140 
141  default:
142  return -EOPNOTSUPP;
143  }
144 }