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* [PATCH v2 0/3] crypto: X25519 supports for ppc64le
@ 2024-05-16 15:19 Danny Tsen
  2024-05-16 15:19 ` [PATCH v2 1/3] crypto: X25519 low-level primitives " Danny Tsen
                   ` (3 more replies)
  0 siblings, 4 replies; 8+ messages in thread
From: Danny Tsen @ 2024-05-16 15:19 UTC (permalink / raw)
  To: linux-crypto
  Cc: herbert, dtsen, nayna, linux-kernel, Danny Tsen, appro, ltcgcw,
	leitao, linuxppc-dev

This patch series provide X25519 support for ppc64le with a new module
curve25519-ppc64le.

The implementation is based on CRYPTOGAMs perl output from x25519-ppc64.pl.
(see https://github.com/dot-asm/cryptogams/)
Modified and added 4 supporting functions.

This patch has passed the selftest by running modprobe
curve25519-ppc64le.

Danny Tsen (3):
  X25519 low-level primitives for ppc64le.
  X25519 core functions for ppc64le
  Update Kconfig and Makefile for ppc64le x25519.

 arch/powerpc/crypto/Kconfig                   |  11 +
 arch/powerpc/crypto/Makefile                  |   2 +
 arch/powerpc/crypto/curve25519-ppc64le-core.c | 299 ++++++++
 arch/powerpc/crypto/curve25519-ppc64le_asm.S  | 671 ++++++++++++++++++
 4 files changed, 983 insertions(+)
 create mode 100644 arch/powerpc/crypto/curve25519-ppc64le-core.c
 create mode 100644 arch/powerpc/crypto/curve25519-ppc64le_asm.S

-- 
2.31.1


^ permalink raw reply	[flat|nested] 8+ messages in thread

* [PATCH v2 1/3] crypto: X25519 low-level primitives for ppc64le.
  2024-05-16 15:19 [PATCH v2 0/3] crypto: X25519 supports for ppc64le Danny Tsen
@ 2024-05-16 15:19 ` Danny Tsen
  2024-05-16 15:19 ` [PATCH v2 2/3] crypto: X25519 core functions " Danny Tsen
                   ` (2 subsequent siblings)
  3 siblings, 0 replies; 8+ messages in thread
From: Danny Tsen @ 2024-05-16 15:19 UTC (permalink / raw)
  To: linux-crypto
  Cc: herbert, dtsen, nayna, linux-kernel, Danny Tsen, appro, ltcgcw,
	leitao, linuxppc-dev

Use the perl output of x25519-ppc64.pl from CRYPTOGAMs
(see https://github.com/dot-asm/cryptogams/) and added four
supporting functions, x25519_fe51_sqr_times, x25519_fe51_frombytes,
x25519_fe51_tobytes and x25519_cswap.

Signed-off-by: Danny Tsen <dtsen@linux.ibm.com>
---
 arch/powerpc/crypto/curve25519-ppc64le_asm.S | 671 +++++++++++++++++++
 1 file changed, 671 insertions(+)
 create mode 100644 arch/powerpc/crypto/curve25519-ppc64le_asm.S

diff --git a/arch/powerpc/crypto/curve25519-ppc64le_asm.S b/arch/powerpc/crypto/curve25519-ppc64le_asm.S
new file mode 100644
index 000000000000..06c1febe24b9
--- /dev/null
+++ b/arch/powerpc/crypto/curve25519-ppc64le_asm.S
@@ -0,0 +1,671 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#
+# This code is taken from CRYPTOGAMs[1] and is included here using the option
+# in the license to distribute the code under the GPL. Therefore this program
+# is free software; you can redistribute it and/or modify it under the terms of
+# the GNU General Public License version 2 as published by the Free Software
+# Foundation.
+#
+# [1] https://github.com/dot-asm/cryptogams/
+
+# Copyright (c) 2006-2017, CRYPTOGAMS by <appro@openssl.org>
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+#
+#       * Redistributions of source code must retain copyright notices,
+#         this list of conditions and the following disclaimer.
+#
+#       * Redistributions in binary form must reproduce the above
+#         copyright notice, this list of conditions and the following
+#         disclaimer in the documentation and/or other materials
+#         provided with the distribution.
+#
+#       * Neither the name of the CRYPTOGAMS nor the names of its
+#         copyright holder and contributors may be used to endorse or
+#         promote products derived from this software without specific
+#         prior written permission.
+#
+# ALTERNATIVELY, provided that this notice is retained in full, this
+# product may be distributed under the terms of the GNU General Public
+# License (GPL), in which case the provisions of the GPL apply INSTEAD OF
+# those given above.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+# ====================================================================
+# Written by Andy Polyakov <appro@openssl.org> for the OpenSSL
+# project. The module is, however, dual licensed under OpenSSL and
+# CRYPTOGAMS licenses depending on where you obtain it. For further
+# details see https://www.openssl.org/~appro/cryptogams/.
+# ====================================================================
+
+#
+# ====================================================================
+# Written and Modified by Danny Tsen <dtsen@us.ibm.com>
+# - Added x25519_fe51_sqr_times, x25519_fe51_frombytes, x25519_fe51_tobytes
+#   and x25519_cswap
+#
+# Copyright 2024- IBM Corp.
+#
+# X25519 lower-level primitives for PPC64.
+#
+
+#include <linux/linkage.h>
+
+.text
+
+.align	5
+SYM_FUNC_START(x25519_fe51_mul)
+
+	stdu	1,-144(1)
+	std	21,56(1)
+	std	22,64(1)
+	std	23,72(1)
+	std	24,80(1)
+	std	25,88(1)
+	std	26,96(1)
+	std	27,104(1)
+	std	28,112(1)
+	std	29,120(1)
+	std	30,128(1)
+	std	31,136(1)
+
+	ld	6,0(5)
+	ld	7,0(4)
+	ld	8,8(4)
+	ld	9,16(4)
+	ld	10,24(4)
+	ld	11,32(4)
+
+	mulld	22,7,6
+	mulhdu	23,7,6
+
+	mulld	24,8,6
+	mulhdu	25,8,6
+
+	mulld	30,11,6
+	mulhdu	31,11,6
+	ld	4,8(5)
+	mulli	11,11,19
+
+	mulld	26,9,6
+	mulhdu	27,9,6
+
+	mulld	28,10,6
+	mulhdu	29,10,6
+	mulld	12,11,4
+	mulhdu	21,11,4
+	addc	22,22,12
+	adde	23,23,21
+
+	mulld	12,7,4
+	mulhdu	21,7,4
+	addc	24,24,12
+	adde	25,25,21
+
+	mulld	12,10,4
+	mulhdu	21,10,4
+	ld	6,16(5)
+	mulli	10,10,19
+	addc	30,30,12
+	adde	31,31,21
+
+	mulld	12,8,4
+	mulhdu	21,8,4
+	addc	26,26,12
+	adde	27,27,21
+
+	mulld	12,9,4
+	mulhdu	21,9,4
+	addc	28,28,12
+	adde	29,29,21
+	mulld	12,10,6
+	mulhdu	21,10,6
+	addc	22,22,12
+	adde	23,23,21
+
+	mulld	12,11,6
+	mulhdu	21,11,6
+	addc	24,24,12
+	adde	25,25,21
+
+	mulld	12,9,6
+	mulhdu	21,9,6
+	ld	4,24(5)
+	mulli	9,9,19
+	addc	30,30,12
+	adde	31,31,21
+
+	mulld	12,7,6
+	mulhdu	21,7,6
+	addc	26,26,12
+	adde	27,27,21
+
+	mulld	12,8,6
+	mulhdu	21,8,6
+	addc	28,28,12
+	adde	29,29,21
+	mulld	12,9,4
+	mulhdu	21,9,4
+	addc	22,22,12
+	adde	23,23,21
+
+	mulld	12,10,4
+	mulhdu	21,10,4
+	addc	24,24,12
+	adde	25,25,21
+
+	mulld	12,8,4
+	mulhdu	21,8,4
+	ld	6,32(5)
+	mulli	8,8,19
+	addc	30,30,12
+	adde	31,31,21
+
+	mulld	12,11,4
+	mulhdu	21,11,4
+	addc	26,26,12
+	adde	27,27,21
+
+	mulld	12,7,4
+	mulhdu	21,7,4
+	addc	28,28,12
+	adde	29,29,21
+	mulld	12,8,6
+	mulhdu	21,8,6
+	addc	22,22,12
+	adde	23,23,21
+
+	mulld	12,9,6
+	mulhdu	21,9,6
+	addc	24,24,12
+	adde	25,25,21
+
+	mulld	12,10,6
+	mulhdu	21,10,6
+	addc	26,26,12
+	adde	27,27,21
+
+	mulld	12,11,6
+	mulhdu	21,11,6
+	addc	28,28,12
+	adde	29,29,21
+
+	mulld	12,7,6
+	mulhdu	21,7,6
+	addc	30,30,12
+	adde	31,31,21
+
+.Lfe51_reduce:
+	li	0,-1
+	srdi	0,0,13
+
+	srdi	12,26,51
+	and	9,26,0
+	insrdi	12,27,51,0
+	srdi	21,22,51
+	and	7,22,0
+	insrdi	21,23,51,0
+	addc	28,28,12
+	addze	29,29
+	addc	24,24,21
+	addze	25,25
+
+	srdi	12,28,51
+	and	10,28,0
+	insrdi	12,29,51,0
+	srdi	21,24,51
+	and	8,24,0
+	insrdi	21,25,51,0
+	addc	30,30,12
+	addze	31,31
+	add	9,9,21
+
+	srdi	12,30,51
+	and	11,30,0
+	insrdi	12,31,51,0
+	mulli	12,12,19
+
+	add	7,7,12
+
+	srdi	21,9,51
+	and	9,9,0
+	add	10,10,21
+
+	srdi	12,7,51
+	and	7,7,0
+	add	8,8,12
+
+	std	9,16(3)
+	std	10,24(3)
+	std	11,32(3)
+	std	7,0(3)
+	std	8,8(3)
+
+	ld	21,56(1)
+	ld	22,64(1)
+	ld	23,72(1)
+	ld	24,80(1)
+	ld	25,88(1)
+	ld	26,96(1)
+	ld	27,104(1)
+	ld	28,112(1)
+	ld	29,120(1)
+	ld	30,128(1)
+	ld	31,136(1)
+	addi	1,1,144
+	blr
+SYM_FUNC_END(x25519_fe51_mul)
+
+.align	5
+SYM_FUNC_START(x25519_fe51_sqr)
+
+	stdu	1,-144(1)
+	std	21,56(1)
+	std	22,64(1)
+	std	23,72(1)
+	std	24,80(1)
+	std	25,88(1)
+	std	26,96(1)
+	std	27,104(1)
+	std	28,112(1)
+	std	29,120(1)
+	std	30,128(1)
+	std	31,136(1)
+
+	ld	7,0(4)
+	ld	8,8(4)
+	ld	9,16(4)
+	ld	10,24(4)
+	ld	11,32(4)
+
+	add	6,7,7
+	mulli	21,11,19
+
+	mulld	22,7,7
+	mulhdu	23,7,7
+	mulld	24,8,6
+	mulhdu	25,8,6
+	mulld	26,9,6
+	mulhdu	27,9,6
+	mulld	28,10,6
+	mulhdu	29,10,6
+	mulld	30,11,6
+	mulhdu	31,11,6
+	add	6,8,8
+	mulld	12,11,21
+	mulhdu	11,11,21
+	addc	28,28,12
+	adde	29,29,11
+
+	mulli	5,10,19
+
+	mulld	12,8,8
+	mulhdu	11,8,8
+	addc	26,26,12
+	adde	27,27,11
+	mulld	12,9,6
+	mulhdu	11,9,6
+	addc	28,28,12
+	adde	29,29,11
+	mulld	12,10,6
+	mulhdu	11,10,6
+	addc	30,30,12
+	adde	31,31,11
+	mulld	12,21,6
+	mulhdu	11,21,6
+	add	6,10,10
+	addc	22,22,12
+	adde	23,23,11
+	mulld	12,10,5
+	mulhdu	10,10,5
+	addc	24,24,12
+	adde	25,25,10
+	mulld	12,6,21
+	mulhdu	10,6,21
+	add	6,9,9
+	addc	26,26,12
+	adde	27,27,10
+
+	mulld	12,9,9
+	mulhdu	10,9,9
+	addc	30,30,12
+	adde	31,31,10
+	mulld	12,5,6
+	mulhdu	10,5,6
+	addc	22,22,12
+	adde	23,23,10
+	mulld	12,21,6
+	mulhdu	10,21,6
+	addc	24,24,12
+	adde	25,25,10
+
+	b	.Lfe51_reduce
+SYM_FUNC_END(x25519_fe51_sqr)
+
+.align	5
+SYM_FUNC_START(x25519_fe51_mul121666)
+
+	stdu	1,-144(1)
+	std	21,56(1)
+	std	22,64(1)
+	std	23,72(1)
+	std	24,80(1)
+	std	25,88(1)
+	std	26,96(1)
+	std	27,104(1)
+	std	28,112(1)
+	std	29,120(1)
+	std	30,128(1)
+	std	31,136(1)
+
+	lis	6,1
+	ori	6,6,56130
+	ld	7,0(4)
+	ld	8,8(4)
+	ld	9,16(4)
+	ld	10,24(4)
+	ld	11,32(4)
+
+	mulld	22,7,6
+	mulhdu	23,7,6
+	mulld	24,8,6
+	mulhdu	25,8,6
+	mulld	26,9,6
+	mulhdu	27,9,6
+	mulld	28,10,6
+	mulhdu	29,10,6
+	mulld	30,11,6
+	mulhdu	31,11,6
+
+	b	.Lfe51_reduce
+SYM_FUNC_END(x25519_fe51_mul121666)
+
+.align	5
+SYM_FUNC_START(x25519_fe51_sqr_times)
+
+	stdu	1,-144(1)
+	std	21,56(1)
+	std	22,64(1)
+	std	23,72(1)
+	std	24,80(1)
+	std	25,88(1)
+	std	26,96(1)
+	std	27,104(1)
+	std	28,112(1)
+	std	29,120(1)
+	std	30,128(1)
+	std	31,136(1)
+
+	ld	7,0(4)
+	ld	8,8(4)
+	ld	9,16(4)
+	ld	10,24(4)
+	ld	11,32(4)
+
+	mtctr	5
+
+.Lsqr_times_loop:
+	add	6,7,7
+	mulli	21,11,19
+
+	mulld	22,7,7
+	mulhdu	23,7,7
+	mulld	24,8,6
+	mulhdu	25,8,6
+	mulld	26,9,6
+	mulhdu	27,9,6
+	mulld	28,10,6
+	mulhdu	29,10,6
+	mulld	30,11,6
+	mulhdu	31,11,6
+	add	6,8,8
+	mulld	12,11,21
+	mulhdu	11,11,21
+	addc	28,28,12
+	adde	29,29,11
+
+	mulli	5,10,19
+
+	mulld	12,8,8
+	mulhdu	11,8,8
+	addc	26,26,12
+	adde	27,27,11
+	mulld	12,9,6
+	mulhdu	11,9,6
+	addc	28,28,12
+	adde	29,29,11
+	mulld	12,10,6
+	mulhdu	11,10,6
+	addc	30,30,12
+	adde	31,31,11
+	mulld	12,21,6
+	mulhdu	11,21,6
+	add	6,10,10
+	addc	22,22,12
+	adde	23,23,11
+	mulld	12,10,5
+	mulhdu	10,10,5
+	addc	24,24,12
+	adde	25,25,10
+	mulld	12,6,21
+	mulhdu	10,6,21
+	add	6,9,9
+	addc	26,26,12
+	adde	27,27,10
+
+	mulld	12,9,9
+	mulhdu	10,9,9
+	addc	30,30,12
+	adde	31,31,10
+	mulld	12,5,6
+	mulhdu	10,5,6
+	addc	22,22,12
+	adde	23,23,10
+	mulld	12,21,6
+	mulhdu	10,21,6
+	addc	24,24,12
+	adde	25,25,10
+
+	# fe51_reduce
+	li	0,-1
+	srdi	0,0,13
+
+	srdi	12,26,51
+	and	9,26,0
+	insrdi	12,27,51,0
+	srdi	21,22,51
+	and	7,22,0
+	insrdi	21,23,51,0
+	addc	28,28,12
+	addze	29,29
+	addc	24,24,21
+	addze	25,25
+
+	srdi	12,28,51
+	and	10,28,0
+	insrdi	12,29,51,0
+	srdi	21,24,51
+	and	8,24,0
+	insrdi	21,25,51,0
+	addc	30,30,12
+	addze	31,31
+	add	9,9,21
+
+	srdi	12,30,51
+	and	11,30,0
+	insrdi	12,31,51,0
+	mulli	12,12,19
+
+	add	7,7,12
+
+	srdi	21,9,51
+	and	9,9,0
+	add	10,10,21
+
+	srdi	12,7,51
+	and	7,7,0
+	add	8,8,12
+
+	bdnz	.Lsqr_times_loop
+
+	std	9,16(3)
+	std	10,24(3)
+	std	11,32(3)
+	std	7,0(3)
+	std	8,8(3)
+
+	ld	21,56(1)
+	ld	22,64(1)
+	ld	23,72(1)
+	ld	24,80(1)
+	ld	25,88(1)
+	ld	26,96(1)
+	ld	27,104(1)
+	ld	28,112(1)
+	ld	29,120(1)
+	ld	30,128(1)
+	ld	31,136(1)
+	addi	1,1,144
+	blr
+SYM_FUNC_END(x25519_fe51_sqr_times)
+
+.align	5
+SYM_FUNC_START(x25519_fe51_frombytes)
+
+	li	12, -1
+	srdi	12, 12, 13	# 0x7ffffffffffff
+
+	ld	5, 0(4)
+	ld	6, 8(4)
+	ld	7, 16(4)
+	ld	8, 24(4)
+
+	srdi	10, 5, 51
+	and	5, 5, 12	# h0
+
+	sldi	11, 6, 13
+	or	11, 10, 11	# h1t
+	srdi	10, 6, 38
+	and	6, 11, 12	# h1
+
+	sldi	11, 7, 26
+	or	10, 10, 11	# h2t
+
+	srdi	11, 7, 25
+	and	7, 10, 12	# h2
+	sldi	10, 8, 39
+	or	11, 11, 10	# h3t
+
+	srdi	9, 8, 12
+	and	8, 11, 12	# h3
+	and	9, 9, 12	# h4
+
+	std	5, 0(3)
+	std	6, 8(3)
+	std	7, 16(3)
+	std	8, 24(3)
+	std	9, 32(3)
+
+	blr
+SYM_FUNC_END(x25519_fe51_frombytes)
+
+.align	5
+SYM_FUNC_START(x25519_fe51_tobytes)
+
+	ld	5, 0(4)
+	ld	6, 8(4)
+	ld	7, 16(4)
+	ld	8, 24(4)
+	ld	9, 32(4)
+
+	li	12, -1
+	srdi	12, 12, 13	# 0x7ffffffffffff
+
+	# Full reducuction
+	addi	10, 5, 19
+	srdi	10, 10, 51
+	add	10, 10, 6
+	srdi	10, 10, 51
+	add	10, 10, 7
+	srdi	10, 10, 51
+	add	10, 10, 8
+	srdi	10, 10, 51
+	add	10, 10, 9
+	srdi	10, 10, 51
+
+	mulli	10, 10, 19
+	add	5, 5, 10
+	srdi	11, 5, 51
+	add	6, 6, 11
+	srdi	11, 6, 51
+	add	7, 7, 11
+	srdi	11, 7, 51
+	add	8, 8, 11
+	srdi	11, 8, 51
+	add	9, 9, 11
+
+	and	5, 5, 12
+	and	6, 6, 12
+	and	7, 7, 12
+	and	8, 8, 12
+	and	9, 9, 12
+
+	sldi	10, 6, 51
+	or	5, 5, 10	# s0
+
+	srdi	11, 6, 13
+	sldi	10, 7, 38
+	or	6, 11, 10	# s1
+
+	srdi	11, 7, 26
+	sldi	10, 8, 25
+	or	7, 11, 10	# s2
+
+	srdi	11, 8, 39
+	sldi	10, 9, 12
+	or	8, 11, 10	# s4
+
+	std	5, 0(3)
+	std	6, 8(3)
+	std	7, 16(3)
+	std	8, 24(3)
+
+	blr
+SYM_FUNC_END(x25519_fe51_tobytes)
+
+.align	5
+SYM_FUNC_START(x25519_cswap)
+
+	li	7, 5
+	neg	6, 5
+	mtctr	7
+
+.Lswap_loop:
+	ld	8, 0(3)
+	ld	9, 0(4)
+	xor	10, 8, 9
+	and	10, 10, 6
+	xor	11, 8, 10
+	xor	12, 9, 10
+	std	11, 0(3)
+	addi	3, 3, 8
+	std	12, 0(4)
+	addi	4, 4, 8
+	bdnz	.Lswap_loop
+
+	blr
+SYM_FUNC_END(x25519_cswap)
-- 
2.31.1


^ permalink raw reply related	[flat|nested] 8+ messages in thread

* [PATCH v2 2/3] crypto: X25519 core functions for ppc64le
  2024-05-16 15:19 [PATCH v2 0/3] crypto: X25519 supports for ppc64le Danny Tsen
  2024-05-16 15:19 ` [PATCH v2 1/3] crypto: X25519 low-level primitives " Danny Tsen
@ 2024-05-16 15:19 ` Danny Tsen
  2024-07-19  0:25   ` Jeff Johnson
  2024-05-16 15:19 ` [PATCH v2 3/3] crypto: Update Kconfig and Makefile for ppc64le x25519 Danny Tsen
  2024-05-31 10:20 ` [PATCH v2 0/3] crypto: X25519 supports for ppc64le Herbert Xu
  3 siblings, 1 reply; 8+ messages in thread
From: Danny Tsen @ 2024-05-16 15:19 UTC (permalink / raw)
  To: linux-crypto
  Cc: herbert, dtsen, nayna, linux-kernel, Danny Tsen, appro, ltcgcw,
	leitao, linuxppc-dev

X25519 core functions to handle scalar multiplication for ppc64le.

Signed-off-by: Danny Tsen <dtsen@linux.ibm.com>
---
 arch/powerpc/crypto/curve25519-ppc64le-core.c | 299 ++++++++++++++++++
 1 file changed, 299 insertions(+)
 create mode 100644 arch/powerpc/crypto/curve25519-ppc64le-core.c

diff --git a/arch/powerpc/crypto/curve25519-ppc64le-core.c b/arch/powerpc/crypto/curve25519-ppc64le-core.c
new file mode 100644
index 000000000000..4e3e44ea4484
--- /dev/null
+++ b/arch/powerpc/crypto/curve25519-ppc64le-core.c
@@ -0,0 +1,299 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2024- IBM Corp.
+ *
+ * X25519 scalar multiplication with 51 bits limbs for PPC64le.
+ *   Based on RFC7748 and AArch64 optimized implementation for X25519
+ *     - Algorithm 1 Scalar multiplication of a variable point
+ */
+
+#include <crypto/curve25519.h>
+#include <crypto/internal/kpp.h>
+
+#include <linux/types.h>
+#include <linux/jump_label.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/scatterlist.h>
+
+#include <linux/cpufeature.h>
+#include <linux/processor.h>
+
+typedef uint64_t fe51[5];
+
+asmlinkage void x25519_fe51_mul(fe51 h, const fe51 f, const fe51 g);
+asmlinkage void x25519_fe51_sqr(fe51 h, const fe51 f);
+asmlinkage void x25519_fe51_mul121666(fe51 h, fe51 f);
+asmlinkage void x25519_fe51_sqr_times(fe51 h, const fe51 f, int n);
+asmlinkage void x25519_fe51_frombytes(fe51 h, const uint8_t *s);
+asmlinkage void x25519_fe51_tobytes(uint8_t *s, const fe51 h);
+asmlinkage void x25519_cswap(fe51 p, fe51 q, unsigned int bit);
+
+#define fmul x25519_fe51_mul
+#define fsqr x25519_fe51_sqr
+#define fmul121666 x25519_fe51_mul121666
+#define fe51_tobytes x25519_fe51_tobytes
+
+static void fadd(fe51 h, const fe51 f, const fe51 g)
+{
+	h[0] = f[0] + g[0];
+	h[1] = f[1] + g[1];
+	h[2] = f[2] + g[2];
+	h[3] = f[3] + g[3];
+	h[4] = f[4] + g[4];
+}
+
+/*
+ * Prime = 2 ** 255 - 19, 255 bits
+ *    (0x7fffffff ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff ffffffed)
+ *
+ * Prime in 5 51-bit limbs
+ */
+static fe51 prime51 = { 0x7ffffffffffed, 0x7ffffffffffff, 0x7ffffffffffff, 0x7ffffffffffff, 0x7ffffffffffff};
+
+static void fsub(fe51 h, const fe51 f, const fe51 g)
+{
+	h[0] = (f[0] + ((prime51[0] * 2))) - g[0];
+	h[1] = (f[1] + ((prime51[1] * 2))) - g[1];
+	h[2] = (f[2] + ((prime51[2] * 2))) - g[2];
+	h[3] = (f[3] + ((prime51[3] * 2))) - g[3];
+	h[4] = (f[4] + ((prime51[4] * 2))) - g[4];
+}
+
+static void fe51_frombytes(fe51 h, const uint8_t *s)
+{
+	/*
+	 * Make sure 64-bit aligned.
+	 */
+	unsigned char sbuf[32+8];
+	unsigned char *sb = PTR_ALIGN((void *)sbuf, 8);
+
+	memcpy(sb, s, 32);
+	x25519_fe51_frombytes(h, sb);
+}
+
+static void finv(fe51 o, const fe51 i)
+{
+	fe51 a0, b, c, t00;
+
+	fsqr(a0, i);
+	x25519_fe51_sqr_times(t00, a0, 2);
+
+	fmul(b, t00, i);
+	fmul(a0, b, a0);
+
+	fsqr(t00, a0);
+
+	fmul(b, t00, b);
+	x25519_fe51_sqr_times(t00, b, 5);
+
+	fmul(b, t00, b);
+	x25519_fe51_sqr_times(t00, b, 10);
+
+	fmul(c, t00, b);
+	x25519_fe51_sqr_times(t00, c, 20);
+
+	fmul(t00, t00, c);
+	x25519_fe51_sqr_times(t00, t00, 10);
+
+	fmul(b, t00, b);
+	x25519_fe51_sqr_times(t00, b, 50);
+
+	fmul(c, t00, b);
+	x25519_fe51_sqr_times(t00, c, 100);
+
+	fmul(t00, t00, c);
+	x25519_fe51_sqr_times(t00, t00, 50);
+
+	fmul(t00, t00, b);
+	x25519_fe51_sqr_times(t00, t00, 5);
+
+	fmul(o, t00, a0);
+}
+
+static void curve25519_fe51(uint8_t out[32], const uint8_t scalar[32],
+			    const uint8_t point[32])
+{
+	fe51 x1, x2, z2, x3, z3;
+	uint8_t s[32];
+	unsigned int swap = 0;
+	int i;
+
+	memcpy(s, scalar, 32);
+	s[0]  &= 0xf8;
+	s[31] &= 0x7f;
+	s[31] |= 0x40;
+	fe51_frombytes(x1, point);
+
+	z2[0] = z2[1] = z2[2] = z2[3] = z2[4] = 0;
+	x3[0] = x1[0];
+	x3[1] = x1[1];
+	x3[2] = x1[2];
+	x3[3] = x1[3];
+	x3[4] = x1[4];
+
+	x2[0] = z3[0] = 1;
+	x2[1] = z3[1] = 0;
+	x2[2] = z3[2] = 0;
+	x2[3] = z3[3] = 0;
+	x2[4] = z3[4] = 0;
+
+	for (i = 254; i >= 0; --i) {
+		unsigned int k_t = 1 & (s[i / 8] >> (i & 7));
+		fe51 a, b, c, d, e;
+		fe51 da, cb, aa, bb;
+		fe51 dacb_p, dacb_m;
+
+		swap ^= k_t;
+		x25519_cswap(x2, x3, swap);
+		x25519_cswap(z2, z3, swap);
+		swap = k_t;
+
+		fsub(b, x2, z2);		// B = x_2 - z_2
+		fadd(a, x2, z2);		// A = x_2 + z_2
+		fsub(d, x3, z3);		// D = x_3 - z_3
+		fadd(c, x3, z3);		// C = x_3 + z_3
+
+		fsqr(bb, b);			// BB = B^2
+		fsqr(aa, a);			// AA = A^2
+		fmul(da, d, a);			// DA = D * A
+		fmul(cb, c, b);			// CB = C * B
+
+		fsub(e, aa, bb);		// E = AA - BB
+		fmul(x2, aa, bb);		// x2 = AA * BB
+		fadd(dacb_p, da, cb);		// DA + CB
+		fsub(dacb_m, da, cb);		// DA - CB
+
+		fmul121666(z3, e);		// 121666 * E
+		fsqr(z2, dacb_m);		// (DA - CB)^2
+		fsqr(x3, dacb_p);		// x3 = (DA + CB)^2
+		fadd(b, bb, z3);		// BB + 121666 * E
+		fmul(z3, x1, z2);		// z3 = x1 * (DA - CB)^2
+		fmul(z2, e, b);		// z2 = e * (BB + (DA + CB)^2)
+	}
+
+	finv(z2, z2);
+	fmul(x2, x2, z2);
+	fe51_tobytes(out, x2);
+}
+
+void curve25519_arch(u8 mypublic[CURVE25519_KEY_SIZE],
+		     const u8 secret[CURVE25519_KEY_SIZE],
+		     const u8 basepoint[CURVE25519_KEY_SIZE])
+{
+	curve25519_fe51(mypublic, secret, basepoint);
+}
+EXPORT_SYMBOL(curve25519_arch);
+
+void curve25519_base_arch(u8 pub[CURVE25519_KEY_SIZE],
+			  const u8 secret[CURVE25519_KEY_SIZE])
+{
+	curve25519_fe51(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_generate_public_key(struct kpp_request *req)
+{
+	struct crypto_kpp *tfm = crypto_kpp_reqtfm(req);
+	const u8 *secret = kpp_tfm_ctx(tfm);
+	u8 buf[CURVE25519_KEY_SIZE];
+	int copied, nbytes;
+
+	if (req->src)
+		return -EINVAL;
+
+	curve25519_base_arch(buf, secret);
+
+	/* 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 int curve25519_compute_shared_secret(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;
+
+	if (!req->src)
+		return -EINVAL;
+
+	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;
+
+	curve25519_arch(buf, secret, public_key);
+
+	/* 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-ppc64le",
+	.base.cra_priority	= 200,
+	.base.cra_module	= THIS_MODULE,
+	.base.cra_ctxsize	= CURVE25519_KEY_SIZE,
+
+	.set_secret		= curve25519_set_secret,
+	.generate_public_key	= curve25519_generate_public_key,
+	.compute_shared_secret	= curve25519_compute_shared_secret,
+	.max_size		= curve25519_max_size,
+};
+
+
+static int __init curve25519_mod_init(void)
+{
+	return IS_REACHABLE(CONFIG_CRYPTO_KPP) ?
+		crypto_register_kpp(&curve25519_alg) : 0;
+}
+
+static void __exit curve25519_mod_exit(void)
+{
+	if (IS_REACHABLE(CONFIG_CRYPTO_KPP))
+		crypto_unregister_kpp(&curve25519_alg);
+}
+
+module_init(curve25519_mod_init);
+module_exit(curve25519_mod_exit);
+
+MODULE_ALIAS_CRYPTO("curve25519");
+MODULE_ALIAS_CRYPTO("curve25519-ppc64le");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Danny Tsen <dtsen@us.ibm.com>");
-- 
2.31.1


^ permalink raw reply related	[flat|nested] 8+ messages in thread

* [PATCH v2 3/3] crypto: Update Kconfig and Makefile for ppc64le x25519.
  2024-05-16 15:19 [PATCH v2 0/3] crypto: X25519 supports for ppc64le Danny Tsen
  2024-05-16 15:19 ` [PATCH v2 1/3] crypto: X25519 low-level primitives " Danny Tsen
  2024-05-16 15:19 ` [PATCH v2 2/3] crypto: X25519 core functions " Danny Tsen
@ 2024-05-16 15:19 ` Danny Tsen
  2024-05-31 10:20 ` [PATCH v2 0/3] crypto: X25519 supports for ppc64le Herbert Xu
  3 siblings, 0 replies; 8+ messages in thread
From: Danny Tsen @ 2024-05-16 15:19 UTC (permalink / raw)
  To: linux-crypto
  Cc: herbert, dtsen, nayna, linux-kernel, Danny Tsen, appro, ltcgcw,
	leitao, linuxppc-dev

Defined CRYPTO_CURVE25519_PPC64 to support X25519 for ppc64le.

Added new module curve25519-ppc64le for X25519.

Signed-off-by: Danny Tsen <dtsen@linux.ibm.com>
---
 arch/powerpc/crypto/Kconfig  | 11 +++++++++++
 arch/powerpc/crypto/Makefile |  2 ++
 2 files changed, 13 insertions(+)

diff --git a/arch/powerpc/crypto/Kconfig b/arch/powerpc/crypto/Kconfig
index 1e201b7ae2fc..09ebcbdfb34f 100644
--- a/arch/powerpc/crypto/Kconfig
+++ b/arch/powerpc/crypto/Kconfig
@@ -2,6 +2,17 @@
 
 menu "Accelerated Cryptographic Algorithms for CPU (powerpc)"
 
+config CRYPTO_CURVE25519_PPC64
+	tristate "Public key crypto: Curve25519 (PowerPC64)"
+	depends on PPC64 && CPU_LITTLE_ENDIAN
+	select CRYPTO_LIB_CURVE25519_GENERIC
+	select CRYPTO_ARCH_HAVE_LIB_CURVE25519
+	help
+	  Curve25519 algorithm
+
+	  Architecture: PowerPC64
+	  - Little-endian
+
 config CRYPTO_CRC32C_VPMSUM
 	tristate "CRC32c"
 	depends on PPC64 && ALTIVEC
diff --git a/arch/powerpc/crypto/Makefile b/arch/powerpc/crypto/Makefile
index fca0e9739869..59808592f0a1 100644
--- a/arch/powerpc/crypto/Makefile
+++ b/arch/powerpc/crypto/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_CRYPTO_AES_GCM_P10) += aes-gcm-p10-crypto.o
 obj-$(CONFIG_CRYPTO_CHACHA20_P10) += chacha-p10-crypto.o
 obj-$(CONFIG_CRYPTO_POLY1305_P10) += poly1305-p10-crypto.o
 obj-$(CONFIG_CRYPTO_DEV_VMX_ENCRYPT) += vmx-crypto.o
+obj-$(CONFIG_CRYPTO_CURVE25519_PPC64) += curve25519-ppc64le.o
 
 aes-ppc-spe-y := aes-spe-core.o aes-spe-keys.o aes-tab-4k.o aes-spe-modes.o aes-spe-glue.o
 md5-ppc-y := md5-asm.o md5-glue.o
@@ -29,6 +30,7 @@ aes-gcm-p10-crypto-y := aes-gcm-p10-glue.o aes-gcm-p10.o ghashp10-ppc.o aesp10-p
 chacha-p10-crypto-y := chacha-p10-glue.o chacha-p10le-8x.o
 poly1305-p10-crypto-y := poly1305-p10-glue.o poly1305-p10le_64.o
 vmx-crypto-objs := vmx.o aesp8-ppc.o ghashp8-ppc.o aes.o aes_cbc.o aes_ctr.o aes_xts.o ghash.o
+curve25519-ppc64le-y := curve25519-ppc64le-core.o curve25519-ppc64le_asm.o
 
 ifeq ($(CONFIG_CPU_LITTLE_ENDIAN),y)
 override flavour := linux-ppc64le
-- 
2.31.1


^ permalink raw reply related	[flat|nested] 8+ messages in thread

* Re: [PATCH v2 0/3] crypto: X25519 supports for ppc64le
  2024-05-16 15:19 [PATCH v2 0/3] crypto: X25519 supports for ppc64le Danny Tsen
                   ` (2 preceding siblings ...)
  2024-05-16 15:19 ` [PATCH v2 3/3] crypto: Update Kconfig and Makefile for ppc64le x25519 Danny Tsen
@ 2024-05-31 10:20 ` Herbert Xu
  2024-05-31 21:10   ` Danny Tsen
  3 siblings, 1 reply; 8+ messages in thread
From: Herbert Xu @ 2024-05-31 10:20 UTC (permalink / raw)
  To: Danny Tsen
  Cc: dtsen, nayna, linux-kernel, appro, linux-crypto, ltcgcw, leitao,
	linuxppc-dev

On Thu, May 16, 2024 at 11:19:54AM -0400, Danny Tsen wrote:
> This patch series provide X25519 support for ppc64le with a new module
> curve25519-ppc64le.
> 
> The implementation is based on CRYPTOGAMs perl output from x25519-ppc64.pl.
> (see https://github.com/dot-asm/cryptogams/)
> Modified and added 4 supporting functions.
> 
> This patch has passed the selftest by running modprobe
> curve25519-ppc64le.
> 
> Danny Tsen (3):
>   X25519 low-level primitives for ppc64le.
>   X25519 core functions for ppc64le
>   Update Kconfig and Makefile for ppc64le x25519.
> 
>  arch/powerpc/crypto/Kconfig                   |  11 +
>  arch/powerpc/crypto/Makefile                  |   2 +
>  arch/powerpc/crypto/curve25519-ppc64le-core.c | 299 ++++++++
>  arch/powerpc/crypto/curve25519-ppc64le_asm.S  | 671 ++++++++++++++++++
>  4 files changed, 983 insertions(+)
>  create mode 100644 arch/powerpc/crypto/curve25519-ppc64le-core.c
>  create mode 100644 arch/powerpc/crypto/curve25519-ppc64le_asm.S
> 
> -- 
> 2.31.1

All applied.  Thanks.
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH v2 0/3] crypto: X25519 supports for ppc64le
  2024-05-31 10:20 ` [PATCH v2 0/3] crypto: X25519 supports for ppc64le Herbert Xu
@ 2024-05-31 21:10   ` Danny Tsen
  0 siblings, 0 replies; 8+ messages in thread
From: Danny Tsen @ 2024-05-31 21:10 UTC (permalink / raw)
  To: Herbert Xu
  Cc: dtsen, nayna, linux-kernel, appro, linux-crypto, ltcgcw, leitao,
	linuxppc-dev

Thanks Herbert.


On 5/31/24 5:20 AM, Herbert Xu wrote:
> On Thu, May 16, 2024 at 11:19:54AM -0400, Danny Tsen wrote:
>> This patch series provide X25519 support for ppc64le with a new module
>> curve25519-ppc64le.
>>
>> The implementation is based on CRYPTOGAMs perl output from x25519-ppc64.pl.
>> (see https://github.com/dot-asm/cryptogams/)
>> Modified and added 4 supporting functions.
>>
>> This patch has passed the selftest by running modprobe
>> curve25519-ppc64le.
>>
>> Danny Tsen (3):
>>    X25519 low-level primitives for ppc64le.
>>    X25519 core functions for ppc64le
>>    Update Kconfig and Makefile for ppc64le x25519.
>>
>>   arch/powerpc/crypto/Kconfig                   |  11 +
>>   arch/powerpc/crypto/Makefile                  |   2 +
>>   arch/powerpc/crypto/curve25519-ppc64le-core.c | 299 ++++++++
>>   arch/powerpc/crypto/curve25519-ppc64le_asm.S  | 671 ++++++++++++++++++
>>   4 files changed, 983 insertions(+)
>>   create mode 100644 arch/powerpc/crypto/curve25519-ppc64le-core.c
>>   create mode 100644 arch/powerpc/crypto/curve25519-ppc64le_asm.S
>>
>> -- 
>> 2.31.1
> All applied.  Thanks.

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH v2 2/3] crypto: X25519 core functions for ppc64le
  2024-05-16 15:19 ` [PATCH v2 2/3] crypto: X25519 core functions " Danny Tsen
@ 2024-07-19  0:25   ` Jeff Johnson
  2024-07-19  0:28     ` Jeff Johnson
  0 siblings, 1 reply; 8+ messages in thread
From: Jeff Johnson @ 2024-07-19  0:25 UTC (permalink / raw)
  To: Danny Tsen, linux-crypto
  Cc: herbert, dtsen, nayna, linux-kernel, appro, ltcgcw, leitao,
	linuxppc-dev

On 5/16/24 08:19, Danny Tsen wrote:
> X25519 core functions to handle scalar multiplication for ppc64le.
> 
> Signed-off-by: Danny Tsen <dtsen@linux.ibm.com>
> ---
>   arch/powerpc/crypto/curve25519-ppc64le-core.c | 299 ++++++++++++++++++
>   1 file changed, 299 insertions(+)
>   create mode 100644 arch/powerpc/crypto/curve25519-ppc64le-core.c
...

> +MODULE_ALIAS_CRYPTO("curve25519");
> +MODULE_ALIAS_CRYPTO("curve25519-ppc64le");
> +MODULE_LICENSE("GPL v2");
> +MODULE_AUTHOR("Danny Tsen <dtsen@us.ibm.com>");

Since commit 1fffe7a34c89 ("script: modpost: emit a warning when the
description is missing"), a module without a MODULE_DESCRIPTION() will
result in a warning with make W=1. I'm in the process of building 
ppc64le with CRYPTO_CURVE25519_PPC64=m to validate my suspicion, but I 
expect this to generate a warning.

Can you submit a follow-up patch that adds a MODULE_DESCRIPTION()?
And since I'm trying to fix all of the existing issues in 6.11, Herbert 
can you push this to Linus when it lands?

Thanks,
/jeff

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH v2 2/3] crypto: X25519 core functions for ppc64le
  2024-07-19  0:25   ` Jeff Johnson
@ 2024-07-19  0:28     ` Jeff Johnson
  0 siblings, 0 replies; 8+ messages in thread
From: Jeff Johnson @ 2024-07-19  0:28 UTC (permalink / raw)
  To: Danny Tsen, linux-crypto
  Cc: herbert, dtsen, nayna, linux-kernel, appro, ltcgcw, leitao,
	linuxppc-dev

On 7/18/2024 5:25 PM, Jeff Johnson wrote:
> On 5/16/24 08:19, Danny Tsen wrote:
>> X25519 core functions to handle scalar multiplication for ppc64le.
>>
>> Signed-off-by: Danny Tsen <dtsen@linux.ibm.com>
>> ---
>>   arch/powerpc/crypto/curve25519-ppc64le-core.c | 299 ++++++++++++++++++
>>   1 file changed, 299 insertions(+)
>>   create mode 100644 arch/powerpc/crypto/curve25519-ppc64le-core.c
> ...
> 
>> +MODULE_ALIAS_CRYPTO("curve25519");
>> +MODULE_ALIAS_CRYPTO("curve25519-ppc64le");
>> +MODULE_LICENSE("GPL v2");
>> +MODULE_AUTHOR("Danny Tsen <dtsen@us.ibm.com>");
> 
> Since commit 1fffe7a34c89 ("script: modpost: emit a warning when the
> description is missing"), a module without a MODULE_DESCRIPTION() will
> result in a warning with make W=1. I'm in the process of building 
> ppc64le with CRYPTO_CURVE25519_PPC64=m to validate my suspicion, but I 
> expect this to generate a warning.
> 
> Can you submit a follow-up patch that adds a MODULE_DESCRIPTION()?
> And since I'm trying to fix all of the existing issues in 6.11, Herbert 
> can you push this to Linus when it lands?

And my build did produce:
WARNING: modpost: missing MODULE_DESCRIPTION() in arch/powerpc/crypto/curve25519-ppc64le.o



^ permalink raw reply	[flat|nested] 8+ messages in thread

end of thread, other threads:[~2024-07-19  0:29 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2024-05-16 15:19 [PATCH v2 0/3] crypto: X25519 supports for ppc64le Danny Tsen
2024-05-16 15:19 ` [PATCH v2 1/3] crypto: X25519 low-level primitives " Danny Tsen
2024-05-16 15:19 ` [PATCH v2 2/3] crypto: X25519 core functions " Danny Tsen
2024-07-19  0:25   ` Jeff Johnson
2024-07-19  0:28     ` Jeff Johnson
2024-05-16 15:19 ` [PATCH v2 3/3] crypto: Update Kconfig and Makefile for ppc64le x25519 Danny Tsen
2024-05-31 10:20 ` [PATCH v2 0/3] crypto: X25519 supports for ppc64le Herbert Xu
2024-05-31 21:10   ` Danny Tsen

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