| /* |
| * crc32-arm64.c - CRC32 and CRC32C using optional ARMv8 instructions |
| * |
| * Module based on crypto/crc32c_generic.c |
| * |
| * CRC32 loop taken from Ed Nevill's Hadoop CRC patch |
| * http://mail-archives.apache.org/mod_mbox/hadoop-common-dev/201406.mbox/%3C1403687030.3355.19.camel%40localhost.localdomain%3E |
| * |
| * Using inline assembly instead of intrinsics in order to be backwards |
| * compatible with older compilers. |
| * |
| * Copyright (C) 2014 Linaro Ltd <yazen.ghannam@linaro.org> |
| * |
| * 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. |
| */ |
| |
| #include <linux/unaligned/access_ok.h> |
| #include <linux/cpufeature.h> |
| #include <linux/init.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/string.h> |
| |
| #include <crypto/internal/hash.h> |
| |
| MODULE_AUTHOR("Yazen Ghannam <yazen.ghannam@linaro.org>"); |
| MODULE_DESCRIPTION("CRC32 and CRC32C using optional ARMv8 instructions"); |
| MODULE_LICENSE("GPL v2"); |
| |
| #define CRC32X(crc, value) __asm__("crc32x %w[c], %w[c], %x[v]":[c]"+r"(crc):[v]"r"(value)) |
| #define CRC32W(crc, value) __asm__("crc32w %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value)) |
| #define CRC32H(crc, value) __asm__("crc32h %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value)) |
| #define CRC32B(crc, value) __asm__("crc32b %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value)) |
| #define CRC32CX(crc, value) __asm__("crc32cx %w[c], %w[c], %x[v]":[c]"+r"(crc):[v]"r"(value)) |
| #define CRC32CW(crc, value) __asm__("crc32cw %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value)) |
| #define CRC32CH(crc, value) __asm__("crc32ch %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value)) |
| #define CRC32CB(crc, value) __asm__("crc32cb %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value)) |
| |
| static u32 crc32_arm64_le_hw(u32 crc, const u8 *p, unsigned int len) |
| { |
| s64 length = len; |
| |
| while ((length -= sizeof(u64)) >= 0) { |
| CRC32X(crc, get_unaligned_le64(p)); |
| p += sizeof(u64); |
| } |
| |
| /* The following is more efficient than the straight loop */ |
| if (length & sizeof(u32)) { |
| CRC32W(crc, get_unaligned_le32(p)); |
| p += sizeof(u32); |
| } |
| if (length & sizeof(u16)) { |
| CRC32H(crc, get_unaligned_le16(p)); |
| p += sizeof(u16); |
| } |
| if (length & sizeof(u8)) |
| CRC32B(crc, *p); |
| |
| return crc; |
| } |
| |
| static u32 crc32c_arm64_le_hw(u32 crc, const u8 *p, unsigned int len) |
| { |
| s64 length = len; |
| |
| while ((length -= sizeof(u64)) >= 0) { |
| CRC32CX(crc, get_unaligned_le64(p)); |
| p += sizeof(u64); |
| } |
| |
| /* The following is more efficient than the straight loop */ |
| if (length & sizeof(u32)) { |
| CRC32CW(crc, get_unaligned_le32(p)); |
| p += sizeof(u32); |
| } |
| if (length & sizeof(u16)) { |
| CRC32CH(crc, get_unaligned_le16(p)); |
| p += sizeof(u16); |
| } |
| if (length & sizeof(u8)) |
| CRC32CB(crc, *p); |
| |
| return crc; |
| } |
| |
| #define CHKSUM_BLOCK_SIZE 1 |
| #define CHKSUM_DIGEST_SIZE 4 |
| |
| struct chksum_ctx { |
| u32 key; |
| }; |
| |
| struct chksum_desc_ctx { |
| u32 crc; |
| }; |
| |
| static int chksum_init(struct shash_desc *desc) |
| { |
| struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm); |
| struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
| |
| ctx->crc = mctx->key; |
| |
| return 0; |
| } |
| |
| /* |
| * Setting the seed allows arbitrary accumulators and flexible XOR policy |
| * If your algorithm starts with ~0, then XOR with ~0 before you set |
| * the seed. |
| */ |
| static int chksum_setkey(struct crypto_shash *tfm, const u8 *key, |
| unsigned int keylen) |
| { |
| struct chksum_ctx *mctx = crypto_shash_ctx(tfm); |
| |
| if (keylen != sizeof(mctx->key)) { |
| crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); |
| return -EINVAL; |
| } |
| mctx->key = get_unaligned_le32(key); |
| return 0; |
| } |
| |
| static int chksum_update(struct shash_desc *desc, const u8 *data, |
| unsigned int length) |
| { |
| struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
| |
| ctx->crc = crc32_arm64_le_hw(ctx->crc, data, length); |
| return 0; |
| } |
| |
| static int chksumc_update(struct shash_desc *desc, const u8 *data, |
| unsigned int length) |
| { |
| struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
| |
| ctx->crc = crc32c_arm64_le_hw(ctx->crc, data, length); |
| return 0; |
| } |
| |
| static int chksum_final(struct shash_desc *desc, u8 *out) |
| { |
| struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
| |
| put_unaligned_le32(ctx->crc, out); |
| return 0; |
| } |
| |
| static int chksumc_final(struct shash_desc *desc, u8 *out) |
| { |
| struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
| |
| put_unaligned_le32(~ctx->crc, out); |
| return 0; |
| } |
| |
| static int __chksum_finup(u32 crc, const u8 *data, unsigned int len, u8 *out) |
| { |
| put_unaligned_le32(crc32_arm64_le_hw(crc, data, len), out); |
| return 0; |
| } |
| |
| static int __chksumc_finup(u32 crc, const u8 *data, unsigned int len, u8 *out) |
| { |
| put_unaligned_le32(~crc32c_arm64_le_hw(crc, data, len), out); |
| return 0; |
| } |
| |
| static int chksum_finup(struct shash_desc *desc, const u8 *data, |
| unsigned int len, u8 *out) |
| { |
| struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
| |
| return __chksum_finup(ctx->crc, data, len, out); |
| } |
| |
| static int chksumc_finup(struct shash_desc *desc, const u8 *data, |
| unsigned int len, u8 *out) |
| { |
| struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
| |
| return __chksumc_finup(ctx->crc, data, len, out); |
| } |
| |
| static int chksum_digest(struct shash_desc *desc, const u8 *data, |
| unsigned int length, u8 *out) |
| { |
| struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm); |
| |
| return __chksum_finup(mctx->key, data, length, out); |
| } |
| |
| static int chksumc_digest(struct shash_desc *desc, const u8 *data, |
| unsigned int length, u8 *out) |
| { |
| struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm); |
| |
| return __chksumc_finup(mctx->key, data, length, out); |
| } |
| |
| static int crc32_cra_init(struct crypto_tfm *tfm) |
| { |
| struct chksum_ctx *mctx = crypto_tfm_ctx(tfm); |
| |
| mctx->key = 0; |
| return 0; |
| } |
| |
| static int crc32c_cra_init(struct crypto_tfm *tfm) |
| { |
| struct chksum_ctx *mctx = crypto_tfm_ctx(tfm); |
| |
| mctx->key = ~0; |
| return 0; |
| } |
| |
| static struct shash_alg crc32_alg = { |
| .digestsize = CHKSUM_DIGEST_SIZE, |
| .setkey = chksum_setkey, |
| .init = chksum_init, |
| .update = chksum_update, |
| .final = chksum_final, |
| .finup = chksum_finup, |
| .digest = chksum_digest, |
| .descsize = sizeof(struct chksum_desc_ctx), |
| .base = { |
| .cra_name = "crc32", |
| .cra_driver_name = "crc32-arm64-hw", |
| .cra_priority = 300, |
| .cra_flags = CRYPTO_ALG_OPTIONAL_KEY, |
| .cra_blocksize = CHKSUM_BLOCK_SIZE, |
| .cra_alignmask = 0, |
| .cra_ctxsize = sizeof(struct chksum_ctx), |
| .cra_module = THIS_MODULE, |
| .cra_init = crc32_cra_init, |
| } |
| }; |
| |
| static struct shash_alg crc32c_alg = { |
| .digestsize = CHKSUM_DIGEST_SIZE, |
| .setkey = chksum_setkey, |
| .init = chksum_init, |
| .update = chksumc_update, |
| .final = chksumc_final, |
| .finup = chksumc_finup, |
| .digest = chksumc_digest, |
| .descsize = sizeof(struct chksum_desc_ctx), |
| .base = { |
| .cra_name = "crc32c", |
| .cra_driver_name = "crc32c-arm64-hw", |
| .cra_priority = 300, |
| .cra_flags = CRYPTO_ALG_OPTIONAL_KEY, |
| .cra_blocksize = CHKSUM_BLOCK_SIZE, |
| .cra_alignmask = 0, |
| .cra_ctxsize = sizeof(struct chksum_ctx), |
| .cra_module = THIS_MODULE, |
| .cra_init = crc32c_cra_init, |
| } |
| }; |
| |
| static int __init crc32_mod_init(void) |
| { |
| int err; |
| |
| err = crypto_register_shash(&crc32_alg); |
| |
| if (err) |
| return err; |
| |
| err = crypto_register_shash(&crc32c_alg); |
| |
| if (err) { |
| crypto_unregister_shash(&crc32_alg); |
| return err; |
| } |
| |
| return 0; |
| } |
| |
| static void __exit crc32_mod_exit(void) |
| { |
| crypto_unregister_shash(&crc32_alg); |
| crypto_unregister_shash(&crc32c_alg); |
| } |
| |
| module_cpu_feature_match(CRC32, crc32_mod_init); |
| module_exit(crc32_mod_exit); |