mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
136 lines
3.6 KiB
136 lines
3.6 KiB
// SPDX-License-Identifier: GPL-2.0 OR MIT |
|
/* |
|
* Copyright (C) 2015-2019 Jason A. Donenfeld <[email protected]>. All Rights Reserved. |
|
* |
|
* Based on public domain code from Daniel J. Bernstein and Peter Schwabe. This |
|
* began from SUPERCOP's curve25519/neon2/scalarmult.s, but has subsequently been |
|
* manually reworked for use in kernel space. |
|
*/ |
|
|
|
#include <asm/hwcap.h> |
|
#include <asm/neon.h> |
|
#include <asm/simd.h> |
|
#include <crypto/internal/kpp.h> |
|
#include <crypto/internal/simd.h> |
|
#include <linux/types.h> |
|
#include <linux/module.h> |
|
#include <linux/init.h> |
|
#include <linux/jump_label.h> |
|
#include <linux/scatterlist.h> |
|
#include <crypto/curve25519.h> |
|
|
|
asmlinkage void curve25519_neon(u8 mypublic[CURVE25519_KEY_SIZE], |
|
const u8 secret[CURVE25519_KEY_SIZE], |
|
const u8 basepoint[CURVE25519_KEY_SIZE]); |
|
|
|
static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_neon); |
|
|
|
void curve25519_arch(u8 out[CURVE25519_KEY_SIZE], |
|
const u8 scalar[CURVE25519_KEY_SIZE], |
|
const u8 point[CURVE25519_KEY_SIZE]) |
|
{ |
|
if (static_branch_likely(&have_neon) && crypto_simd_usable()) { |
|
kernel_neon_begin(); |
|
curve25519_neon(out, scalar, point); |
|
kernel_neon_end(); |
|
} else { |
|
curve25519_generic(out, scalar, point); |
|
} |
|
} |
|
EXPORT_SYMBOL(curve25519_arch); |
|
|
|
void curve25519_base_arch(u8 pub[CURVE25519_KEY_SIZE], |
|
const u8 secret[CURVE25519_KEY_SIZE]) |
|
{ |
|
return curve25519_arch(pub, secret, curve25519_base_point); |
|
} |
|
EXPORT_SYMBOL(curve25519_base_arch); |
|
|
|
static int curve25519_set_secret(struct crypto_kpp *tfm, const void *buf, |
|
unsigned int len) |
|
{ |
|
u8 *secret = kpp_tfm_ctx(tfm); |
|
|
|
if (!len) |
|
curve25519_generate_secret(secret); |
|
else if (len == CURVE25519_KEY_SIZE && |
|
crypto_memneq(buf, curve25519_null_point, CURVE25519_KEY_SIZE)) |
|
memcpy(secret, buf, CURVE25519_KEY_SIZE); |
|
else |
|
return -EINVAL; |
|
return 0; |
|
} |
|
|
|
static int curve25519_compute_value(struct kpp_request *req) |
|
{ |
|
struct crypto_kpp *tfm = crypto_kpp_reqtfm(req); |
|
const u8 *secret = kpp_tfm_ctx(tfm); |
|
u8 public_key[CURVE25519_KEY_SIZE]; |
|
u8 buf[CURVE25519_KEY_SIZE]; |
|
int copied, nbytes; |
|
u8 const *bp; |
|
|
|
if (req->src) { |
|
copied = sg_copy_to_buffer(req->src, |
|
sg_nents_for_len(req->src, |
|
CURVE25519_KEY_SIZE), |
|
public_key, CURVE25519_KEY_SIZE); |
|
if (copied != CURVE25519_KEY_SIZE) |
|
return -EINVAL; |
|
bp = public_key; |
|
} else { |
|
bp = curve25519_base_point; |
|
} |
|
|
|
curve25519_arch(buf, secret, bp); |
|
|
|
/* might want less than we've got */ |
|
nbytes = min_t(size_t, CURVE25519_KEY_SIZE, req->dst_len); |
|
copied = sg_copy_from_buffer(req->dst, sg_nents_for_len(req->dst, |
|
nbytes), |
|
buf, nbytes); |
|
if (copied != nbytes) |
|
return -EINVAL; |
|
return 0; |
|
} |
|
|
|
static unsigned int curve25519_max_size(struct crypto_kpp *tfm) |
|
{ |
|
return CURVE25519_KEY_SIZE; |
|
} |
|
|
|
static struct kpp_alg curve25519_alg = { |
|
.base.cra_name = "curve25519", |
|
.base.cra_driver_name = "curve25519-neon", |
|
.base.cra_priority = 200, |
|
.base.cra_module = THIS_MODULE, |
|
.base.cra_ctxsize = CURVE25519_KEY_SIZE, |
|
|
|
.set_secret = curve25519_set_secret, |
|
.generate_public_key = curve25519_compute_value, |
|
.compute_shared_secret = curve25519_compute_value, |
|
.max_size = curve25519_max_size, |
|
}; |
|
|
|
static int __init mod_init(void) |
|
{ |
|
if (elf_hwcap & HWCAP_NEON) { |
|
static_branch_enable(&have_neon); |
|
return IS_REACHABLE(CONFIG_CRYPTO_KPP) ? |
|
crypto_register_kpp(&curve25519_alg) : 0; |
|
} |
|
return 0; |
|
} |
|
|
|
static void __exit mod_exit(void) |
|
{ |
|
if (IS_REACHABLE(CONFIG_CRYPTO_KPP) && elf_hwcap & HWCAP_NEON) |
|
crypto_unregister_kpp(&curve25519_alg); |
|
} |
|
|
|
module_init(mod_init); |
|
module_exit(mod_exit); |
|
|
|
MODULE_ALIAS_CRYPTO("curve25519"); |
|
MODULE_ALIAS_CRYPTO("curve25519-neon"); |
|
MODULE_LICENSE("GPL v2");
|
|
|