1 /** 2 * AES CBC 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/algapi.h> 24 #include <linux/module.h> 25 #include <linux/types.h> 26 #include <linux/crypto.h> 27 #include <asm/vio.h> 28 29 #include "nx_csbcpb.h" 30 #include "nx.h" 31 32 33 static int cbc_aes_nx_set_key(struct crypto_tfm *tfm, 34 const u8 *in_key, 35 unsigned int key_len) 36 { 37 struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(tfm); 38 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; 39 40 nx_ctx_init(nx_ctx, HCOP_FC_AES); 41 42 switch (key_len) { 43 case AES_KEYSIZE_128: 44 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_128); 45 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_128]; 46 break; 47 case AES_KEYSIZE_192: 48 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_192); 49 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_192]; 50 break; 51 case AES_KEYSIZE_256: 52 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_256); 53 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_256]; 54 break; 55 default: 56 return -EINVAL; 57 } 58 59 csbcpb->cpb.hdr.mode = NX_MODE_AES_CBC; 60 memcpy(csbcpb->cpb.aes_cbc.key, in_key, key_len); 61 62 return 0; 63 } 64 65 static int cbc_aes_nx_crypt(struct blkcipher_desc *desc, 66 struct scatterlist *dst, 67 struct scatterlist *src, 68 unsigned int nbytes, 69 int enc) 70 { 71 struct nx_crypto_ctx *nx_ctx = crypto_blkcipher_ctx(desc->tfm); 72 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; 73 unsigned long irq_flags; 74 unsigned int processed = 0, to_process; 75 int rc; 76 77 spin_lock_irqsave(&nx_ctx->lock, irq_flags); 78 79 if (enc) 80 NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT; 81 else 82 NX_CPB_FDM(csbcpb) &= ~NX_FDM_ENDE_ENCRYPT; 83 84 do { 85 to_process = nbytes - processed; 86 87 rc = nx_build_sg_lists(nx_ctx, desc, dst, src, &to_process, 88 processed, csbcpb->cpb.aes_cbc.iv); 89 if (rc) 90 goto out; 91 92 if (!nx_ctx->op.inlen || !nx_ctx->op.outlen) { 93 rc = -EINVAL; 94 goto out; 95 } 96 97 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op, 98 desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP); 99 if (rc) 100 goto out; 101 102 memcpy(desc->info, csbcpb->cpb.aes_cbc.cv, AES_BLOCK_SIZE); 103 atomic_inc(&(nx_ctx->stats->aes_ops)); 104 atomic64_add(csbcpb->csb.processed_byte_count, 105 &(nx_ctx->stats->aes_bytes)); 106 107 processed += to_process; 108 } while (processed < nbytes); 109 out: 110 spin_unlock_irqrestore(&nx_ctx->lock, irq_flags); 111 return rc; 112 } 113 114 static int cbc_aes_nx_encrypt(struct blkcipher_desc *desc, 115 struct scatterlist *dst, 116 struct scatterlist *src, 117 unsigned int nbytes) 118 { 119 return cbc_aes_nx_crypt(desc, dst, src, nbytes, 1); 120 } 121 122 static int cbc_aes_nx_decrypt(struct blkcipher_desc *desc, 123 struct scatterlist *dst, 124 struct scatterlist *src, 125 unsigned int nbytes) 126 { 127 return cbc_aes_nx_crypt(desc, dst, src, nbytes, 0); 128 } 129 130 struct crypto_alg nx_cbc_aes_alg = { 131 .cra_name = "cbc(aes)", 132 .cra_driver_name = "cbc-aes-nx", 133 .cra_priority = 300, 134 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER, 135 .cra_blocksize = AES_BLOCK_SIZE, 136 .cra_ctxsize = sizeof(struct nx_crypto_ctx), 137 .cra_type = &crypto_blkcipher_type, 138 .cra_alignmask = 0xf, 139 .cra_module = THIS_MODULE, 140 .cra_init = nx_crypto_ctx_aes_cbc_init, 141 .cra_exit = nx_crypto_ctx_exit, 142 .cra_blkcipher = { 143 .min_keysize = AES_MIN_KEY_SIZE, 144 .max_keysize = AES_MAX_KEY_SIZE, 145 .ivsize = AES_BLOCK_SIZE, 146 .setkey = cbc_aes_nx_set_key, 147 .encrypt = cbc_aes_nx_encrypt, 148 .decrypt = cbc_aes_nx_decrypt, 149 } 150 }; 151