1 /** 2 * AES CTR routines supporting the Power 7+ Nest Accelerators driver 3 * 4 * Copyright (C) 2011-2012 International Business Machines Inc. 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; version 2 only. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 18 * 19 * Author: Kent Yoder <yoder1@us.ibm.com> 20 */ 21 22 #include <crypto/aes.h> 23 #include <crypto/ctr.h> 24 #include <crypto/algapi.h> 25 #include <linux/module.h> 26 #include <linux/types.h> 27 #include <linux/crypto.h> 28 #include <asm/vio.h> 29 30 #include "nx_csbcpb.h" 31 #include "nx.h" 32 33 34 static int ctr_aes_nx_set_key(struct crypto_tfm *tfm, 35 const u8 *in_key, 36 unsigned int key_len) 37 { 38 struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(tfm); 39 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; 40 41 nx_ctx_init(nx_ctx, HCOP_FC_AES); 42 43 switch (key_len) { 44 case AES_KEYSIZE_128: 45 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_128); 46 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_128]; 47 break; 48 case AES_KEYSIZE_192: 49 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_192); 50 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_192]; 51 break; 52 case AES_KEYSIZE_256: 53 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_256); 54 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_256]; 55 break; 56 default: 57 return -EINVAL; 58 } 59 60 csbcpb->cpb.hdr.mode = NX_MODE_AES_CTR; 61 memcpy(csbcpb->cpb.aes_ctr.key, in_key, key_len); 62 63 return 0; 64 } 65 66 static int ctr3686_aes_nx_set_key(struct crypto_tfm *tfm, 67 const u8 *in_key, 68 unsigned int key_len) 69 { 70 struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(tfm); 71 72 if (key_len < CTR_RFC3686_NONCE_SIZE) 73 return -EINVAL; 74 75 memcpy(nx_ctx->priv.ctr.nonce, 76 in_key + key_len - CTR_RFC3686_NONCE_SIZE, 77 CTR_RFC3686_NONCE_SIZE); 78 79 key_len -= CTR_RFC3686_NONCE_SIZE; 80 81 return ctr_aes_nx_set_key(tfm, in_key, key_len); 82 } 83 84 static int ctr_aes_nx_crypt(struct blkcipher_desc *desc, 85 struct scatterlist *dst, 86 struct scatterlist *src, 87 unsigned int nbytes) 88 { 89 struct nx_crypto_ctx *nx_ctx = crypto_blkcipher_ctx(desc->tfm); 90 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; 91 unsigned long irq_flags; 92 unsigned int processed = 0, to_process; 93 int rc; 94 95 spin_lock_irqsave(&nx_ctx->lock, irq_flags); 96 97 do { 98 to_process = nbytes - processed; 99 100 rc = nx_build_sg_lists(nx_ctx, desc, dst, src, &to_process, 101 processed, csbcpb->cpb.aes_ctr.iv); 102 if (rc) 103 goto out; 104 105 if (!nx_ctx->op.inlen || !nx_ctx->op.outlen) { 106 rc = -EINVAL; 107 goto out; 108 } 109 110 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op, 111 desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP); 112 if (rc) 113 goto out; 114 115 memcpy(desc->info, csbcpb->cpb.aes_cbc.cv, AES_BLOCK_SIZE); 116 117 atomic_inc(&(nx_ctx->stats->aes_ops)); 118 atomic64_add(csbcpb->csb.processed_byte_count, 119 &(nx_ctx->stats->aes_bytes)); 120 121 processed += to_process; 122 } while (processed < nbytes); 123 out: 124 spin_unlock_irqrestore(&nx_ctx->lock, irq_flags); 125 return rc; 126 } 127 128 static int ctr3686_aes_nx_crypt(struct blkcipher_desc *desc, 129 struct scatterlist *dst, 130 struct scatterlist *src, 131 unsigned int nbytes) 132 { 133 struct nx_crypto_ctx *nx_ctx = crypto_blkcipher_ctx(desc->tfm); 134 u8 iv[16]; 135 136 memcpy(iv, nx_ctx->priv.ctr.nonce, CTR_RFC3686_IV_SIZE); 137 memcpy(iv + CTR_RFC3686_NONCE_SIZE, 138 desc->info, CTR_RFC3686_IV_SIZE); 139 iv[12] = iv[13] = iv[14] = 0; 140 iv[15] = 1; 141 142 desc->info = iv; 143 144 return ctr_aes_nx_crypt(desc, dst, src, nbytes); 145 } 146 147 struct crypto_alg nx_ctr3686_aes_alg = { 148 .cra_name = "rfc3686(ctr(aes))", 149 .cra_driver_name = "rfc3686-ctr-aes-nx", 150 .cra_priority = 300, 151 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER, 152 .cra_blocksize = 1, 153 .cra_ctxsize = sizeof(struct nx_crypto_ctx), 154 .cra_type = &crypto_blkcipher_type, 155 .cra_module = THIS_MODULE, 156 .cra_init = nx_crypto_ctx_aes_ctr_init, 157 .cra_exit = nx_crypto_ctx_exit, 158 .cra_blkcipher = { 159 .min_keysize = AES_MIN_KEY_SIZE + CTR_RFC3686_NONCE_SIZE, 160 .max_keysize = AES_MAX_KEY_SIZE + CTR_RFC3686_NONCE_SIZE, 161 .ivsize = CTR_RFC3686_IV_SIZE, 162 .setkey = ctr3686_aes_nx_set_key, 163 .encrypt = ctr3686_aes_nx_crypt, 164 .decrypt = ctr3686_aes_nx_crypt, 165 } 166 }; 167