| /* |
| * aes-ce-glue.c - wrapper code for ARMv8 AES |
| * |
| * Copyright (C) 2015 Linaro Ltd <ard.biesheuvel@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 <asm/hwcap.h> |
| #include <asm/neon.h> |
| #include <asm/hwcap.h> |
| #include <crypto/aes.h> |
| #include <crypto/internal/simd.h> |
| #include <crypto/internal/skcipher.h> |
| #include <linux/module.h> |
| #include <crypto/xts.h> |
| |
| MODULE_DESCRIPTION("AES-ECB/CBC/CTR/XTS using ARMv8 Crypto Extensions"); |
| MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>"); |
| MODULE_LICENSE("GPL v2"); |
| |
| /* defined in aes-ce-core.S */ |
| asmlinkage u32 ce_aes_sub(u32 input); |
| asmlinkage void ce_aes_invert(void *dst, void *src); |
| |
| asmlinkage void ce_aes_ecb_encrypt(u8 out[], u8 const in[], u8 const rk[], |
| int rounds, int blocks); |
| asmlinkage void ce_aes_ecb_decrypt(u8 out[], u8 const in[], u8 const rk[], |
| int rounds, int blocks); |
| |
| asmlinkage void ce_aes_cbc_encrypt(u8 out[], u8 const in[], u8 const rk[], |
| int rounds, int blocks, u8 iv[]); |
| asmlinkage void ce_aes_cbc_decrypt(u8 out[], u8 const in[], u8 const rk[], |
| int rounds, int blocks, u8 iv[]); |
| |
| asmlinkage void ce_aes_ctr_encrypt(u8 out[], u8 const in[], u8 const rk[], |
| int rounds, int blocks, u8 ctr[]); |
| |
| asmlinkage void ce_aes_xts_encrypt(u8 out[], u8 const in[], u8 const rk1[], |
| int rounds, int blocks, u8 iv[], |
| u8 const rk2[], int first); |
| asmlinkage void ce_aes_xts_decrypt(u8 out[], u8 const in[], u8 const rk1[], |
| int rounds, int blocks, u8 iv[], |
| u8 const rk2[], int first); |
| |
| struct aes_block { |
| u8 b[AES_BLOCK_SIZE]; |
| }; |
| |
| static int num_rounds(struct crypto_aes_ctx *ctx) |
| { |
| /* |
| * # of rounds specified by AES: |
| * 128 bit key 10 rounds |
| * 192 bit key 12 rounds |
| * 256 bit key 14 rounds |
| * => n byte key => 6 + (n/4) rounds |
| */ |
| return 6 + ctx->key_length / 4; |
| } |
| |
| static int ce_aes_expandkey(struct crypto_aes_ctx *ctx, const u8 *in_key, |
| unsigned int key_len) |
| { |
| /* |
| * The AES key schedule round constants |
| */ |
| static u8 const rcon[] = { |
| 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, |
| }; |
| |
| u32 kwords = key_len / sizeof(u32); |
| struct aes_block *key_enc, *key_dec; |
| int i, j; |
| |
| if (key_len != AES_KEYSIZE_128 && |
| key_len != AES_KEYSIZE_192 && |
| key_len != AES_KEYSIZE_256) |
| return -EINVAL; |
| |
| memcpy(ctx->key_enc, in_key, key_len); |
| ctx->key_length = key_len; |
| |
| kernel_neon_begin(); |
| for (i = 0; i < sizeof(rcon); i++) { |
| u32 *rki = ctx->key_enc + (i * kwords); |
| u32 *rko = rki + kwords; |
| |
| #ifndef CONFIG_CPU_BIG_ENDIAN |
| rko[0] = ror32(ce_aes_sub(rki[kwords - 1]), 8); |
| rko[0] = rko[0] ^ rki[0] ^ rcon[i]; |
| #else |
| rko[0] = rol32(ce_aes_sub(rki[kwords - 1]), 8); |
| rko[0] = rko[0] ^ rki[0] ^ (rcon[i] << 24); |
| #endif |
| rko[1] = rko[0] ^ rki[1]; |
| rko[2] = rko[1] ^ rki[2]; |
| rko[3] = rko[2] ^ rki[3]; |
| |
| if (key_len == AES_KEYSIZE_192) { |
| if (i >= 7) |
| break; |
| rko[4] = rko[3] ^ rki[4]; |
| rko[5] = rko[4] ^ rki[5]; |
| } else if (key_len == AES_KEYSIZE_256) { |
| if (i >= 6) |
| break; |
| rko[4] = ce_aes_sub(rko[3]) ^ rki[4]; |
| rko[5] = rko[4] ^ rki[5]; |
| rko[6] = rko[5] ^ rki[6]; |
| rko[7] = rko[6] ^ rki[7]; |
| } |
| } |
| |
| /* |
| * Generate the decryption keys for the Equivalent Inverse Cipher. |
| * This involves reversing the order of the round keys, and applying |
| * the Inverse Mix Columns transformation on all but the first and |
| * the last one. |
| */ |
| key_enc = (struct aes_block *)ctx->key_enc; |
| key_dec = (struct aes_block *)ctx->key_dec; |
| j = num_rounds(ctx); |
| |
| key_dec[0] = key_enc[j]; |
| for (i = 1, j--; j > 0; i++, j--) |
| ce_aes_invert(key_dec + i, key_enc + j); |
| key_dec[i] = key_enc[0]; |
| |
| kernel_neon_end(); |
| return 0; |
| } |
| |
| static int ce_aes_setkey(struct crypto_skcipher *tfm, const u8 *in_key, |
| unsigned int key_len) |
| { |
| struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm); |
| int ret; |
| |
| ret = ce_aes_expandkey(ctx, in_key, key_len); |
| if (!ret) |
| return 0; |
| |
| crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); |
| return -EINVAL; |
| } |
| |
| struct crypto_aes_xts_ctx { |
| struct crypto_aes_ctx key1; |
| struct crypto_aes_ctx __aligned(8) key2; |
| }; |
| |
| static int xts_set_key(struct crypto_skcipher *tfm, const u8 *in_key, |
| unsigned int key_len) |
| { |
| struct crypto_aes_xts_ctx *ctx = crypto_skcipher_ctx(tfm); |
| int ret; |
| |
| ret = xts_verify_key(tfm, in_key, key_len); |
| if (ret) |
| return ret; |
| |
| ret = ce_aes_expandkey(&ctx->key1, in_key, key_len / 2); |
| if (!ret) |
| ret = ce_aes_expandkey(&ctx->key2, &in_key[key_len / 2], |
| key_len / 2); |
| if (!ret) |
| return 0; |
| |
| crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); |
| return -EINVAL; |
| } |
| |
| static int ecb_encrypt(struct skcipher_request *req) |
| { |
| struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); |
| struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm); |
| struct skcipher_walk walk; |
| unsigned int blocks; |
| int err; |
| |
| err = skcipher_walk_virt(&walk, req, true); |
| |
| kernel_neon_begin(); |
| while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) { |
| ce_aes_ecb_encrypt(walk.dst.virt.addr, walk.src.virt.addr, |
| (u8 *)ctx->key_enc, num_rounds(ctx), blocks); |
| err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE); |
| } |
| kernel_neon_end(); |
| return err; |
| } |
| |
| static int ecb_decrypt(struct skcipher_request *req) |
| { |
| struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); |
| struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm); |
| struct skcipher_walk walk; |
| unsigned int blocks; |
| int err; |
| |
| err = skcipher_walk_virt(&walk, req, true); |
| |
| kernel_neon_begin(); |
| while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) { |
| ce_aes_ecb_decrypt(walk.dst.virt.addr, walk.src.virt.addr, |
| (u8 *)ctx->key_dec, num_rounds(ctx), blocks); |
| err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE); |
| } |
| kernel_neon_end(); |
| return err; |
| } |
| |
| static int cbc_encrypt(struct skcipher_request *req) |
| { |
| struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); |
| struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm); |
| struct skcipher_walk walk; |
| unsigned int blocks; |
| int err; |
| |
| err = skcipher_walk_virt(&walk, req, true); |
| |
| kernel_neon_begin(); |
| while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) { |
| ce_aes_cbc_encrypt(walk.dst.virt.addr, walk.src.virt.addr, |
| (u8 *)ctx->key_enc, num_rounds(ctx), blocks, |
| walk.iv); |
| err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE); |
| } |
| kernel_neon_end(); |
| return err; |
| } |
| |
| static int cbc_decrypt(struct skcipher_request *req) |
| { |
| struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); |
| struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm); |
| struct skcipher_walk walk; |
| unsigned int blocks; |
| int err; |
| |
| err = skcipher_walk_virt(&walk, req, true); |
| |
| kernel_neon_begin(); |
| while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) { |
| ce_aes_cbc_decrypt(walk.dst.virt.addr, walk.src.virt.addr, |
| (u8 *)ctx->key_dec, num_rounds(ctx), blocks, |
| walk.iv); |
| err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE); |
| } |
| kernel_neon_end(); |
| return err; |
| } |
| |
| static int ctr_encrypt(struct skcipher_request *req) |
| { |
| struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); |
| struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm); |
| struct skcipher_walk walk; |
| int err, blocks; |
| |
| err = skcipher_walk_virt(&walk, req, true); |
| |
| kernel_neon_begin(); |
| while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) { |
| ce_aes_ctr_encrypt(walk.dst.virt.addr, walk.src.virt.addr, |
| (u8 *)ctx->key_enc, num_rounds(ctx), blocks, |
| walk.iv); |
| err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE); |
| } |
| if (walk.nbytes) { |
| u8 __aligned(8) tail[AES_BLOCK_SIZE]; |
| unsigned int nbytes = walk.nbytes; |
| u8 *tdst = walk.dst.virt.addr; |
| u8 *tsrc = walk.src.virt.addr; |
| |
| /* |
| * Minimum alignment is 8 bytes, so if nbytes is <= 8, we need |
| * to tell aes_ctr_encrypt() to only read half a block. |
| */ |
| blocks = (nbytes <= 8) ? -1 : 1; |
| |
| ce_aes_ctr_encrypt(tail, tsrc, (u8 *)ctx->key_enc, |
| num_rounds(ctx), blocks, walk.iv); |
| memcpy(tdst, tail, nbytes); |
| err = skcipher_walk_done(&walk, 0); |
| } |
| kernel_neon_end(); |
| |
| return err; |
| } |
| |
| static int xts_encrypt(struct skcipher_request *req) |
| { |
| struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); |
| struct crypto_aes_xts_ctx *ctx = crypto_skcipher_ctx(tfm); |
| int err, first, rounds = num_rounds(&ctx->key1); |
| struct skcipher_walk walk; |
| unsigned int blocks; |
| |
| err = skcipher_walk_virt(&walk, req, true); |
| |
| kernel_neon_begin(); |
| for (first = 1; (blocks = (walk.nbytes / AES_BLOCK_SIZE)); first = 0) { |
| ce_aes_xts_encrypt(walk.dst.virt.addr, walk.src.virt.addr, |
| (u8 *)ctx->key1.key_enc, rounds, blocks, |
| walk.iv, (u8 *)ctx->key2.key_enc, first); |
| err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE); |
| } |
| kernel_neon_end(); |
| |
| return err; |
| } |
| |
| static int xts_decrypt(struct skcipher_request *req) |
| { |
| struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); |
| struct crypto_aes_xts_ctx *ctx = crypto_skcipher_ctx(tfm); |
| int err, first, rounds = num_rounds(&ctx->key1); |
| struct skcipher_walk walk; |
| unsigned int blocks; |
| |
| err = skcipher_walk_virt(&walk, req, true); |
| |
| kernel_neon_begin(); |
| for (first = 1; (blocks = (walk.nbytes / AES_BLOCK_SIZE)); first = 0) { |
| ce_aes_xts_decrypt(walk.dst.virt.addr, walk.src.virt.addr, |
| (u8 *)ctx->key1.key_dec, rounds, blocks, |
| walk.iv, (u8 *)ctx->key2.key_enc, first); |
| err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE); |
| } |
| kernel_neon_end(); |
| |
| return err; |
| } |
| |
| static struct skcipher_alg aes_algs[] = { { |
| .base = { |
| .cra_name = "__ecb(aes)", |
| .cra_driver_name = "__ecb-aes-ce", |
| .cra_priority = 300, |
| .cra_flags = CRYPTO_ALG_INTERNAL, |
| .cra_blocksize = AES_BLOCK_SIZE, |
| .cra_ctxsize = sizeof(struct crypto_aes_ctx), |
| .cra_alignmask = 7, |
| .cra_module = THIS_MODULE, |
| }, |
| .min_keysize = AES_MIN_KEY_SIZE, |
| .max_keysize = AES_MAX_KEY_SIZE, |
| .setkey = ce_aes_setkey, |
| .encrypt = ecb_encrypt, |
| .decrypt = ecb_decrypt, |
| }, { |
| .base = { |
| .cra_name = "__cbc(aes)", |
| .cra_driver_name = "__cbc-aes-ce", |
| .cra_priority = 300, |
| .cra_flags = CRYPTO_ALG_INTERNAL, |
| .cra_blocksize = AES_BLOCK_SIZE, |
| .cra_ctxsize = sizeof(struct crypto_aes_ctx), |
| .cra_alignmask = 7, |
| .cra_module = THIS_MODULE, |
| }, |
| .min_keysize = AES_MIN_KEY_SIZE, |
| .max_keysize = AES_MAX_KEY_SIZE, |
| .ivsize = AES_BLOCK_SIZE, |
| .setkey = ce_aes_setkey, |
| .encrypt = cbc_encrypt, |
| .decrypt = cbc_decrypt, |
| }, { |
| .base = { |
| .cra_name = "__ctr(aes)", |
| .cra_driver_name = "__ctr-aes-ce", |
| .cra_priority = 300, |
| .cra_flags = CRYPTO_ALG_INTERNAL, |
| .cra_blocksize = 1, |
| .cra_ctxsize = sizeof(struct crypto_aes_ctx), |
| .cra_alignmask = 7, |
| .cra_module = THIS_MODULE, |
| }, |
| .min_keysize = AES_MIN_KEY_SIZE, |
| .max_keysize = AES_MAX_KEY_SIZE, |
| .ivsize = AES_BLOCK_SIZE, |
| .chunksize = AES_BLOCK_SIZE, |
| .setkey = ce_aes_setkey, |
| .encrypt = ctr_encrypt, |
| .decrypt = ctr_encrypt, |
| }, { |
| .base = { |
| .cra_name = "__xts(aes)", |
| .cra_driver_name = "__xts-aes-ce", |
| .cra_priority = 300, |
| .cra_flags = CRYPTO_ALG_INTERNAL, |
| .cra_blocksize = AES_BLOCK_SIZE, |
| .cra_ctxsize = sizeof(struct crypto_aes_xts_ctx), |
| .cra_alignmask = 7, |
| .cra_module = THIS_MODULE, |
| }, |
| .min_keysize = 2 * AES_MIN_KEY_SIZE, |
| .max_keysize = 2 * AES_MAX_KEY_SIZE, |
| .ivsize = AES_BLOCK_SIZE, |
| .setkey = xts_set_key, |
| .encrypt = xts_encrypt, |
| .decrypt = xts_decrypt, |
| } }; |
| |
| static struct simd_skcipher_alg *aes_simd_algs[ARRAY_SIZE(aes_algs)]; |
| |
| static void aes_exit(void) |
| { |
| int i; |
| |
| for (i = 0; i < ARRAY_SIZE(aes_simd_algs) && aes_simd_algs[i]; i++) |
| simd_skcipher_free(aes_simd_algs[i]); |
| |
| crypto_unregister_skciphers(aes_algs, ARRAY_SIZE(aes_algs)); |
| } |
| |
| static int __init aes_init(void) |
| { |
| struct simd_skcipher_alg *simd; |
| const char *basename; |
| const char *algname; |
| const char *drvname; |
| int err; |
| int i; |
| |
| if (!(elf_hwcap2 & HWCAP2_AES)) |
| return -ENODEV; |
| |
| err = crypto_register_skciphers(aes_algs, ARRAY_SIZE(aes_algs)); |
| if (err) |
| return err; |
| |
| for (i = 0; i < ARRAY_SIZE(aes_algs); i++) { |
| algname = aes_algs[i].base.cra_name + 2; |
| drvname = aes_algs[i].base.cra_driver_name + 2; |
| basename = aes_algs[i].base.cra_driver_name; |
| simd = simd_skcipher_create_compat(algname, drvname, basename); |
| err = PTR_ERR(simd); |
| if (IS_ERR(simd)) |
| goto unregister_simds; |
| |
| aes_simd_algs[i] = simd; |
| } |
| |
| return 0; |
| |
| unregister_simds: |
| aes_exit(); |
| return err; |
| } |
| |
| module_init(aes_init); |
| module_exit(aes_exit); |