1 // SPDX-License-Identifier: GPL-2.0-only 2 /** 3 * AES routines supporting VMX instructions on the Power 8 4 * 5 * Copyright (C) 2015 International Business Machines Inc. 6 * 7 * Author: Marcelo Henrique Cerri <mhcerri@br.ibm.com> 8 */ 9 10 #include <linux/types.h> 11 #include <linux/err.h> 12 #include <linux/crypto.h> 13 #include <linux/delay.h> 14 #include <asm/simd.h> 15 #include <asm/switch_to.h> 16 #include <crypto/aes.h> 17 #include <crypto/internal/simd.h> 18 19 #include "aesp8-ppc.h" 20 21 struct p8_aes_ctx { 22 struct crypto_cipher *fallback; 23 struct aes_key enc_key; 24 struct aes_key dec_key; 25 }; 26 27 static int p8_aes_init(struct crypto_tfm *tfm) 28 { 29 const char *alg = crypto_tfm_alg_name(tfm); 30 struct crypto_cipher *fallback; 31 struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm); 32 33 fallback = crypto_alloc_cipher(alg, 0, CRYPTO_ALG_NEED_FALLBACK); 34 if (IS_ERR(fallback)) { 35 printk(KERN_ERR 36 "Failed to allocate transformation for '%s': %ld\n", 37 alg, PTR_ERR(fallback)); 38 return PTR_ERR(fallback); 39 } 40 41 crypto_cipher_set_flags(fallback, 42 crypto_cipher_get_flags((struct 43 crypto_cipher *) 44 tfm)); 45 ctx->fallback = fallback; 46 47 return 0; 48 } 49 50 static void p8_aes_exit(struct crypto_tfm *tfm) 51 { 52 struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm); 53 54 if (ctx->fallback) { 55 crypto_free_cipher(ctx->fallback); 56 ctx->fallback = NULL; 57 } 58 } 59 60 static int p8_aes_setkey(struct crypto_tfm *tfm, const u8 *key, 61 unsigned int keylen) 62 { 63 int ret; 64 struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm); 65 66 preempt_disable(); 67 pagefault_disable(); 68 enable_kernel_vsx(); 69 ret = aes_p8_set_encrypt_key(key, keylen * 8, &ctx->enc_key); 70 ret |= aes_p8_set_decrypt_key(key, keylen * 8, &ctx->dec_key); 71 disable_kernel_vsx(); 72 pagefault_enable(); 73 preempt_enable(); 74 75 ret |= crypto_cipher_setkey(ctx->fallback, key, keylen); 76 77 return ret ? -EINVAL : 0; 78 } 79 80 static void p8_aes_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src) 81 { 82 struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm); 83 84 if (!crypto_simd_usable()) { 85 crypto_cipher_encrypt_one(ctx->fallback, dst, src); 86 } else { 87 preempt_disable(); 88 pagefault_disable(); 89 enable_kernel_vsx(); 90 aes_p8_encrypt(src, dst, &ctx->enc_key); 91 disable_kernel_vsx(); 92 pagefault_enable(); 93 preempt_enable(); 94 } 95 } 96 97 static void p8_aes_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src) 98 { 99 struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm); 100 101 if (!crypto_simd_usable()) { 102 crypto_cipher_decrypt_one(ctx->fallback, dst, src); 103 } else { 104 preempt_disable(); 105 pagefault_disable(); 106 enable_kernel_vsx(); 107 aes_p8_decrypt(src, dst, &ctx->dec_key); 108 disable_kernel_vsx(); 109 pagefault_enable(); 110 preempt_enable(); 111 } 112 } 113 114 struct crypto_alg p8_aes_alg = { 115 .cra_name = "aes", 116 .cra_driver_name = "p8_aes", 117 .cra_module = THIS_MODULE, 118 .cra_priority = 1000, 119 .cra_type = NULL, 120 .cra_flags = CRYPTO_ALG_TYPE_CIPHER | CRYPTO_ALG_NEED_FALLBACK, 121 .cra_alignmask = 0, 122 .cra_blocksize = AES_BLOCK_SIZE, 123 .cra_ctxsize = sizeof(struct p8_aes_ctx), 124 .cra_init = p8_aes_init, 125 .cra_exit = p8_aes_exit, 126 .cra_cipher = { 127 .cia_min_keysize = AES_MIN_KEY_SIZE, 128 .cia_max_keysize = AES_MAX_KEY_SIZE, 129 .cia_setkey = p8_aes_setkey, 130 .cia_encrypt = p8_aes_encrypt, 131 .cia_decrypt = p8_aes_decrypt, 132 }, 133 }; 134