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 int rc; 74 75 if (nbytes > nx_ctx->ap->databytelen) 76 return -EINVAL; 77 78 if (enc) 79 NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT; 80 else 81 NX_CPB_FDM(csbcpb) &= ~NX_FDM_ENDE_ENCRYPT; 82 83 rc = nx_build_sg_lists(nx_ctx, desc, dst, src, nbytes, 84 csbcpb->cpb.aes_cbc.iv); 85 if (rc) 86 goto out; 87 88 if (!nx_ctx->op.inlen || !nx_ctx->op.outlen) { 89 rc = -EINVAL; 90 goto out; 91 } 92 93 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op, 94 desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP); 95 if (rc) 96 goto out; 97 98 atomic_inc(&(nx_ctx->stats->aes_ops)); 99 atomic64_add(csbcpb->csb.processed_byte_count, 100 &(nx_ctx->stats->aes_bytes)); 101 out: 102 return rc; 103 } 104 105 static int cbc_aes_nx_encrypt(struct blkcipher_desc *desc, 106 struct scatterlist *dst, 107 struct scatterlist *src, 108 unsigned int nbytes) 109 { 110 return cbc_aes_nx_crypt(desc, dst, src, nbytes, 1); 111 } 112 113 static int cbc_aes_nx_decrypt(struct blkcipher_desc *desc, 114 struct scatterlist *dst, 115 struct scatterlist *src, 116 unsigned int nbytes) 117 { 118 return cbc_aes_nx_crypt(desc, dst, src, nbytes, 0); 119 } 120 121 struct crypto_alg nx_cbc_aes_alg = { 122 .cra_name = "cbc(aes)", 123 .cra_driver_name = "cbc-aes-nx", 124 .cra_priority = 300, 125 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER, 126 .cra_blocksize = AES_BLOCK_SIZE, 127 .cra_ctxsize = sizeof(struct nx_crypto_ctx), 128 .cra_type = &crypto_blkcipher_type, 129 .cra_alignmask = 0xf, 130 .cra_module = THIS_MODULE, 131 .cra_init = nx_crypto_ctx_aes_cbc_init, 132 .cra_exit = nx_crypto_ctx_exit, 133 .cra_blkcipher = { 134 .min_keysize = AES_MIN_KEY_SIZE, 135 .max_keysize = AES_MAX_KEY_SIZE, 136 .ivsize = AES_BLOCK_SIZE, 137 .setkey = cbc_aes_nx_set_key, 138 .encrypt = cbc_aes_nx_encrypt, 139 .decrypt = cbc_aes_nx_decrypt, 140 } 141 }; 142