18c2ecf20Sopenharmony_ci// SPDX-License-Identifier: GPL-2.0-or-later
28c2ecf20Sopenharmony_ci/* 32-bit compatibility syscall for 64-bit systems for DH operations
38c2ecf20Sopenharmony_ci *
48c2ecf20Sopenharmony_ci * Copyright (C) 2016 Stephan Mueller <smueller@chronox.de>
58c2ecf20Sopenharmony_ci */
68c2ecf20Sopenharmony_ci
78c2ecf20Sopenharmony_ci#include <linux/uaccess.h>
88c2ecf20Sopenharmony_ci
98c2ecf20Sopenharmony_ci#include "internal.h"
108c2ecf20Sopenharmony_ci
118c2ecf20Sopenharmony_ci/*
128c2ecf20Sopenharmony_ci * Perform the DH computation or DH based key derivation.
138c2ecf20Sopenharmony_ci *
148c2ecf20Sopenharmony_ci * If successful, 0 will be returned.
158c2ecf20Sopenharmony_ci */
168c2ecf20Sopenharmony_cilong compat_keyctl_dh_compute(struct keyctl_dh_params __user *params,
178c2ecf20Sopenharmony_ci			      char __user *buffer, size_t buflen,
188c2ecf20Sopenharmony_ci			      struct compat_keyctl_kdf_params __user *kdf)
198c2ecf20Sopenharmony_ci{
208c2ecf20Sopenharmony_ci	struct keyctl_kdf_params kdfcopy;
218c2ecf20Sopenharmony_ci	struct compat_keyctl_kdf_params compat_kdfcopy;
228c2ecf20Sopenharmony_ci
238c2ecf20Sopenharmony_ci	if (!kdf)
248c2ecf20Sopenharmony_ci		return __keyctl_dh_compute(params, buffer, buflen, NULL);
258c2ecf20Sopenharmony_ci
268c2ecf20Sopenharmony_ci	if (copy_from_user(&compat_kdfcopy, kdf, sizeof(compat_kdfcopy)) != 0)
278c2ecf20Sopenharmony_ci		return -EFAULT;
288c2ecf20Sopenharmony_ci
298c2ecf20Sopenharmony_ci	kdfcopy.hashname = compat_ptr(compat_kdfcopy.hashname);
308c2ecf20Sopenharmony_ci	kdfcopy.otherinfo = compat_ptr(compat_kdfcopy.otherinfo);
318c2ecf20Sopenharmony_ci	kdfcopy.otherinfolen = compat_kdfcopy.otherinfolen;
328c2ecf20Sopenharmony_ci	memcpy(kdfcopy.__spare, compat_kdfcopy.__spare,
338c2ecf20Sopenharmony_ci	       sizeof(kdfcopy.__spare));
348c2ecf20Sopenharmony_ci
358c2ecf20Sopenharmony_ci	return __keyctl_dh_compute(params, buffer, buflen, &kdfcopy);
368c2ecf20Sopenharmony_ci}
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