162306a36Sopenharmony_ci// SPDX-License-Identifier: GPL-2.0-or-later
262306a36Sopenharmony_ci/* 32-bit compatibility syscall for 64-bit systems for DH operations
362306a36Sopenharmony_ci *
462306a36Sopenharmony_ci * Copyright (C) 2016 Stephan Mueller <smueller@chronox.de>
562306a36Sopenharmony_ci */
662306a36Sopenharmony_ci
762306a36Sopenharmony_ci#include <linux/uaccess.h>
862306a36Sopenharmony_ci
962306a36Sopenharmony_ci#include "internal.h"
1062306a36Sopenharmony_ci
1162306a36Sopenharmony_ci/*
1262306a36Sopenharmony_ci * Perform the DH computation or DH based key derivation.
1362306a36Sopenharmony_ci *
1462306a36Sopenharmony_ci * If successful, 0 will be returned.
1562306a36Sopenharmony_ci */
1662306a36Sopenharmony_cilong compat_keyctl_dh_compute(struct keyctl_dh_params __user *params,
1762306a36Sopenharmony_ci			      char __user *buffer, size_t buflen,
1862306a36Sopenharmony_ci			      struct compat_keyctl_kdf_params __user *kdf)
1962306a36Sopenharmony_ci{
2062306a36Sopenharmony_ci	struct keyctl_kdf_params kdfcopy;
2162306a36Sopenharmony_ci	struct compat_keyctl_kdf_params compat_kdfcopy;
2262306a36Sopenharmony_ci
2362306a36Sopenharmony_ci	if (!kdf)
2462306a36Sopenharmony_ci		return __keyctl_dh_compute(params, buffer, buflen, NULL);
2562306a36Sopenharmony_ci
2662306a36Sopenharmony_ci	if (copy_from_user(&compat_kdfcopy, kdf, sizeof(compat_kdfcopy)) != 0)
2762306a36Sopenharmony_ci		return -EFAULT;
2862306a36Sopenharmony_ci
2962306a36Sopenharmony_ci	kdfcopy.hashname = compat_ptr(compat_kdfcopy.hashname);
3062306a36Sopenharmony_ci	kdfcopy.otherinfo = compat_ptr(compat_kdfcopy.otherinfo);
3162306a36Sopenharmony_ci	kdfcopy.otherinfolen = compat_kdfcopy.otherinfolen;
3262306a36Sopenharmony_ci	memcpy(kdfcopy.__spare, compat_kdfcopy.__spare,
3362306a36Sopenharmony_ci	       sizeof(kdfcopy.__spare));
3462306a36Sopenharmony_ci
3562306a36Sopenharmony_ci	return __keyctl_dh_compute(params, buffer, buflen, &kdfcopy);
3662306a36Sopenharmony_ci}
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