xref: /linux/security/keys/compat.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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 	default:
136 		return -EOPNOTSUPP;
137 	}
138 }
139