From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf1-f194.google.com ([209.85.210.194]:44193 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387872AbeKFCSU (ORCPT ); Mon, 5 Nov 2018 21:18:20 -0500 Received: by mail-pf1-f194.google.com with SMTP id j13-v6so4699279pff.11 for ; Mon, 05 Nov 2018 08:57:45 -0800 (PST) From: Jian-Hong Pan Subject: [PATCH V2 5/7] net: maclorawan: Implement the crypto of maclorawan module Date: Tue, 6 Nov 2018 00:55:43 +0800 Message-Id: <20181105165544.5215-6-starnight@g.ncu.edu.tw> In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-wpan-owner@vger.kernel.org List-ID: To: =?UTF-8?q?Andreas=20F=C3=A4rber?= Cc: netdev@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Marcel Holtmann , "David S . Miller" , Dollar Chen , Ken Yu , linux-wpan@vger.kernel.org, Stefan Schmidt , Jian-Hong Pan Implement the crypto for encryption/decryption and message integrity code (MIC) according to LoRaWAN(TM) Specification Ver. 1.0.2. Signed-off-by: Jian-Hong Pan --- V2: - Split the LoRaWAN class module patch in V1 into LoRaWAN socket and LoRaWAN Soft MAC modules - Rename the lrwsec files to crypto files - Modify for Big/Little-Endian - Use SPDX license identifiers net/maclorawan/crypto.c | 209 ++++++++++++++++++++++++++++++++++++++++ net/maclorawan/crypto.h | 27 ++++++ 2 files changed, 236 insertions(+) create mode 100644 net/maclorawan/crypto.c create mode 100644 net/maclorawan/crypto.h diff --git a/net/maclorawan/crypto.c b/net/maclorawan/crypto.c new file mode 100644 index 000000000000..a839fd074ad8 --- /dev/null +++ b/net/maclorawan/crypto.c @@ -0,0 +1,209 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later OR BSD-3-Clause */ +/*- + * LoRaWAN soft MAC + * + * Copyright (c) 2018 Jian-Hong, Pan + * + */ + +#include +#include +#include +#include "crypto.h" + +struct crypto_shash * +lrw_mic_key_setup(u8 *k, size_t k_len) +{ + char *algo = "cmac(aes)"; + struct crypto_shash *tfm; + int err; + + tfm = crypto_alloc_shash(algo, 0, 0); + if (!IS_ERR(tfm)) { + err = crypto_shash_setkey(tfm, k, k_len); + if (err) { + crypto_free_shash(tfm); + tfm = NULL; + } + } + + return tfm; +} + +int +lrw_aes_cmac(struct crypto_shash *tfm, u8 *bz, u8 *data, size_t len, u8 *out) +{ + SHASH_DESC_ON_STACK(desc, tfm); + int err; + + desc->tfm = tfm; + + err = crypto_shash_init(desc); + if (err) + goto lrw_aes_cmac_end; + + err = crypto_shash_update(desc, bz, 16); + if (err) + goto lrw_aes_cmac_end; + + err = crypto_shash_update(desc, data, len); + if (err) + goto lrw_aes_cmac_end; + + err = crypto_shash_final(desc, out); + +lrw_aes_cmac_end: + return err; +} + +int +lrw_set_bzero(u8 dir, u32 devaddr, u32 fcnt, u8 len, u8 *bz) +{ + __le32 le_devaddr = cpu_to_le32(devaddr); + __le32 _fcnt = cpu_to_le32(fcnt); + + bz[0] = 0x49; + memset(bz + 1, 0x00, 4); + bz[5] = dir; + memcpy(bz + 6, &le_devaddr, 4); + memcpy(bz + 10, &_fcnt, 4); + bz[14] = 0x00; + bz[15] = len; + + return 0; +} + +int +lrw_calc_mic(struct crypto_shash *tfm, + u8 dir, u32 devaddr, u32 fcnt, u8* buf, size_t len, u8 *mic4) +{ + u8 mic[16]; + u8 bz[16]; + int err; + + /* According to LoRaWAN Specification Version 1.0.2 + * - 4.4 Massege Integrity Code (MIC) */ + lrw_set_bzero(dir, devaddr, fcnt, len, bz); + err = lrw_aes_cmac(tfm, bz, buf, len, mic); + if (!err) + memcpy(mic4, mic, 4); + + return err; +} + +void +lrw_mic_key_free(struct crypto_shash *tfm) +{ + crypto_free_shash(tfm); +} + +struct crypto_skcipher * +lrw_aes_enc_key_setup(char *algo, u8 *k, size_t k_len) +{ + struct crypto_skcipher *tfm; + int err; + + tfm = crypto_alloc_skcipher(algo, 0, CRYPTO_ALG_ASYNC); + if (!IS_ERR(tfm)) { + err = crypto_skcipher_setkey(tfm, k, k_len); + if (err) { + crypto_free_skcipher(tfm); + tfm = NULL; + } + } + + return tfm; +} + +struct crypto_skcipher * +lrw_encrypt_key_setup(u8 *k, size_t k_len) +{ + return lrw_aes_enc_key_setup("cbc(aes)", k, k_len); +} + +int +lrw_aes_enc(struct crypto_skcipher *tfm, u8 *in, size_t len, u8 *out) +{ + u8 iv[16]; + struct scatterlist src, dst; + SKCIPHER_REQUEST_ON_STACK(req, tfm); + int err; + + memset(iv, 0, 16); + /* The buffer for sg_init_one cannot be a global or const local + * (will confuse the scatterlist) */ + sg_init_one(&src, in, len); + sg_init_one(&dst, out, len); + + skcipher_request_set_tfm(req, tfm); + skcipher_request_set_callback(req, 0, NULL, NULL); + skcipher_request_set_crypt(req, &src, &dst, len, iv); + err = crypto_skcipher_encrypt(req); + skcipher_request_zero(req); + + return err; +} + +#define LRW_SEQUENCE_OF_BLOCK_LEN 16 + +int +lrw_set_sob(u8 dir, u32 devaddr, u32 fcnt, u8 index, u8 *sob) +{ + __le32 le_devaddr = cpu_to_le32(devaddr); + __le32 _fcnt = cpu_to_le32(fcnt); + + sob[0] = 0x01; + memset(sob + 1, 0x00, 4); + sob[5] = dir; + memcpy(sob + 6, &le_devaddr, 4); + memcpy(sob + 10, &_fcnt, 4); + sob[14] = 0x00; + sob[15] = index; + + return 0; +} + +int +lrw_encrypt_sob(struct crypto_skcipher *tfm, u8 *sob) +{ + return lrw_aes_enc(tfm, sob, LRW_SEQUENCE_OF_BLOCK_LEN, sob); +} + +int +lrw_encrypt_buf(struct crypto_skcipher *tfm, + u8 dir, u32 devaddr, u32 fcnt, u8 *buf, size_t len) +{ + u8 sob[LRW_SEQUENCE_OF_BLOCK_LEN]; + u8 i, j; + + /* According to LoRaWAN Specification Version 1.0.2 + * - 4.3.3 MAC Frame Payload Encryption (FRMPayload) */ + for (i = 0; (i * LRW_SEQUENCE_OF_BLOCK_LEN) < len; i++) { + lrw_set_sob(dir, devaddr, fcnt, i, sob); + lrw_encrypt_sob(tfm, sob); + for (j = 0; (i * LRW_SEQUENCE_OF_BLOCK_LEN + j) < len; j++) + buf[i * LRW_SEQUENCE_OF_BLOCK_LEN + j] ^= sob[j]; + } + + return 0; +} + +int +lrw_decrypt_buf(struct crypto_skcipher *tfm, + u8 dir, u32 devaddr, u32 fcnt, u8 *buf, size_t len) +{ + /* Accoding to XOR swap algorithm */ + return lrw_encrypt_buf(tfm, dir, devaddr, fcnt, buf, len); +} + +void +lrw_aes_enc_key_free(struct crypto_skcipher *tfm) +{ + crypto_free_skcipher(tfm); +} + +void +lrw_encrypt_key_free(struct crypto_skcipher *tfm) +{ + lrw_aes_enc_key_free(tfm); +} diff --git a/net/maclorawan/crypto.h b/net/maclorawan/crypto.h new file mode 100644 index 000000000000..2ede02efb8c6 --- /dev/null +++ b/net/maclorawan/crypto.h @@ -0,0 +1,27 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later OR BSD-3-Clause */ +/*- + * LoRaWAN soft MAC + * + * Copyright (c) 2018 Jian-Hong, Pan + * + */ + +#ifndef __LORAWAN_CRYPTO_H__ +#define __LORAWAN_CRYPTO_H__ + +#include +#include + +struct crypto_shash *lrw_mic_key_setup(u8 *k, size_t k_len); +int lrw_calc_mic(struct crypto_shash *tfm, + u8 dir, u32 devaddr, u32 fcnt, u8* buf, size_t len, u8 *mic4); +void lrw_mic_key_free(struct crypto_shash *tfm); + +struct crypto_skcipher *lrw_encrypt_key_setup(u8 *k, size_t k_len); +int lrw_encrypt_buf(struct crypto_skcipher *tfm, + u8 dir, u32 devaddr, u32 fcnt, u8 *buf, size_t len); +int lrw_decrypt_buf(struct crypto_skcipher *tfm, + u8 dir, u32 devaddr, u32 fcnt, u8 *buf, size_t len); +void lrw_encrypt_key_free(struct crypto_skcipher *tfm); + +#endif -- 2.19.1