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/cipher.h> 18 #include <crypto/internal/simd.h> 19 20 #include "aesp8-ppc.h" 21 22 struct p8_aes_ctx { 23 struct crypto_cipher *fallback; 24 struct aes_key enc_key; 25 struct aes_key dec_key; 26 }; 27 28 static int p8_aes_init(struct crypto_tfm *tfm) 29 { 30 const char *alg = crypto_tfm_alg_name(tfm); 31 struct crypto_cipher *fallback; 32 struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm); 33 34 fallback = crypto_alloc_cipher(alg, 0, CRYPTO_ALG_NEED_FALLBACK); 35 if (IS_ERR(fallback)) { 36 printk(KERN_ERR 37 "Failed to allocate transformation for '%s': %ld\n", 38 alg, PTR_ERR(fallback)); 39 return PTR_ERR(fallback); 40 } 41 42 crypto_cipher_set_flags(fallback, 43 crypto_cipher_get_flags((struct 44 crypto_cipher *) 45 tfm)); 46 ctx->fallback = fallback; 47 48 return 0; 49 } 50 51 static void p8_aes_exit(struct crypto_tfm *tfm) 52 { 53 struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm); 54 55 if (ctx->fallback) { 56 crypto_free_cipher(ctx->fallback); 57 ctx->fallback = NULL; 58 } 59 } 60 61 static int p8_aes_setkey(struct crypto_tfm *tfm, const u8 *key, 62 unsigned int keylen) 63 { 64 int ret; 65 struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm); 66 67 preempt_disable(); 68 pagefault_disable(); 69 enable_kernel_vsx(); 70 ret = aes_p8_set_encrypt_key(key, keylen * 8, &ctx->enc_key); 71 ret |= aes_p8_set_decrypt_key(key, keylen * 8, &ctx->dec_key); 72 disable_kernel_vsx(); 73 pagefault_enable(); 74 preempt_enable(); 75 76 ret |= crypto_cipher_setkey(ctx->fallback, key, keylen); 77 78 return ret ? -EINVAL : 0; 79 } 80 81 static void p8_aes_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src) 82 { 83 struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm); 84 85 if (!crypto_simd_usable()) { 86 crypto_cipher_encrypt_one(ctx->fallback, dst, src); 87 } else { 88 preempt_disable(); 89 pagefault_disable(); 90 enable_kernel_vsx(); 91 aes_p8_encrypt(src, dst, &ctx->enc_key); 92 disable_kernel_vsx(); 93 pagefault_enable(); 94 preempt_enable(); 95 } 96 } 97 98 static void p8_aes_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src) 99 { 100 struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm); 101 102 if (!crypto_simd_usable()) { 103 crypto_cipher_decrypt_one(ctx->fallback, dst, src); 104 } else { 105 preempt_disable(); 106 pagefault_disable(); 107 enable_kernel_vsx(); 108 aes_p8_decrypt(src, dst, &ctx->dec_key); 109 disable_kernel_vsx(); 110 pagefault_enable(); 111 preempt_enable(); 112 } 113 } 114 115 struct crypto_alg p8_aes_alg = { 116 .cra_name = "aes", 117 .cra_driver_name = "p8_aes", 118 .cra_module = THIS_MODULE, 119 .cra_priority = 1000, 120 .cra_type = NULL, 121 .cra_flags = CRYPTO_ALG_TYPE_CIPHER | CRYPTO_ALG_NEED_FALLBACK, 122 .cra_alignmask = 0, 123 .cra_blocksize = AES_BLOCK_SIZE, 124 .cra_ctxsize = sizeof(struct p8_aes_ctx), 125 .cra_init = p8_aes_init, 126 .cra_exit = p8_aes_exit, 127 .cra_cipher = { 128 .cia_min_keysize = AES_MIN_KEY_SIZE, 129 .cia_max_keysize = AES_MAX_KEY_SIZE, 130 .cia_setkey = p8_aes_setkey, 131 .cia_encrypt = p8_aes_encrypt, 132 .cia_decrypt = p8_aes_decrypt, 133 }, 134 }; 135