1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* 32-bit compatibility syscall for 64-bit systems for DH operations
3 *
4 * Copyright (C) 2016 Stephan Mueller <smueller@chronox.de>
5 */
6
7 #include <linux/uaccess.h>
8
9 #include "internal.h"
10
11 /*
12 * Perform the DH computation or DH based key derivation.
13 *
14 * If successful, 0 will be returned.
15 */
compat_keyctl_dh_compute(struct keyctl_dh_params __user * params,char __user * buffer,size_t buflen,struct compat_keyctl_kdf_params __user * kdf)16 long compat_keyctl_dh_compute(struct keyctl_dh_params __user *params,
17 char __user *buffer, size_t buflen,
18 struct compat_keyctl_kdf_params __user *kdf)
19 {
20 struct keyctl_kdf_params kdfcopy;
21 struct compat_keyctl_kdf_params compat_kdfcopy;
22
23 if (!kdf)
24 return __keyctl_dh_compute(params, buffer, buflen, NULL);
25
26 if (copy_from_user(&compat_kdfcopy, kdf, sizeof(compat_kdfcopy)) != 0)
27 return -EFAULT;
28
29 kdfcopy.hashname = compat_ptr(compat_kdfcopy.hashname);
30 kdfcopy.otherinfo = compat_ptr(compat_kdfcopy.otherinfo);
31 kdfcopy.otherinfolen = compat_kdfcopy.otherinfolen;
32 memcpy(kdfcopy.__spare, compat_kdfcopy.__spare,
33 sizeof(kdfcopy.__spare));
34
35 return __keyctl_dh_compute(params, buffer, buflen, &kdfcopy);
36 }
37