1/**
2 * AES ECB 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
33static int ecb_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 = (struct nx_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_ECB;
60	memcpy(csbcpb->cpb.aes_ecb.key, in_key, key_len);
61
62	return 0;
63}
64
65static int ecb_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, NULL);
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		atomic_inc(&(nx_ctx->stats->aes_ops));
103		atomic64_add(csbcpb->csb.processed_byte_count,
104			     &(nx_ctx->stats->aes_bytes));
105
106		processed += to_process;
107	} while (processed < nbytes);
108
109out:
110	spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
111	return rc;
112}
113
114static int ecb_aes_nx_encrypt(struct blkcipher_desc *desc,
115			      struct scatterlist    *dst,
116			      struct scatterlist    *src,
117			      unsigned int           nbytes)
118{
119	return ecb_aes_nx_crypt(desc, dst, src, nbytes, 1);
120}
121
122static int ecb_aes_nx_decrypt(struct blkcipher_desc *desc,
123			      struct scatterlist    *dst,
124			      struct scatterlist    *src,
125			      unsigned int           nbytes)
126{
127	return ecb_aes_nx_crypt(desc, dst, src, nbytes, 0);
128}
129
130struct crypto_alg nx_ecb_aes_alg = {
131	.cra_name        = "ecb(aes)",
132	.cra_driver_name = "ecb-aes-nx",
133	.cra_priority    = 300,
134	.cra_flags       = CRYPTO_ALG_TYPE_BLKCIPHER,
135	.cra_blocksize   = AES_BLOCK_SIZE,
136	.cra_alignmask   = 0xf,
137	.cra_ctxsize     = sizeof(struct nx_crypto_ctx),
138	.cra_type        = &crypto_blkcipher_type,
139	.cra_module      = THIS_MODULE,
140	.cra_init        = nx_crypto_ctx_aes_ecb_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		.setkey      = ecb_aes_nx_set_key,
146		.encrypt     = ecb_aes_nx_encrypt,
147		.decrypt     = ecb_aes_nx_decrypt,
148	}
149};
150