xref: /openbmc/linux/drivers/crypto/nx/nx-aes-ecb.c (revision 4f6cce39)
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 
33 static 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 
65 static 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 
109 out:
110 	spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
111 	return rc;
112 }
113 
114 static 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 
122 static 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 
130 struct 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