1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * AES CBC routines supporting the Power 7+ Nest Accelerators driver
4 *
5 * Copyright (C) 2011-2012 International Business Machines Inc.
6 *
7 * Author: Kent Yoder <yoder1@us.ibm.com>
8 */
9
10 #include <crypto/aes.h>
11 #include <crypto/algapi.h>
12 #include <linux/module.h>
13 #include <linux/types.h>
14 #include <linux/crypto.h>
15 #include <asm/vio.h>
16
17 #include "nx_csbcpb.h"
18 #include "nx.h"
19
20
cbc_aes_nx_set_key(struct crypto_skcipher * tfm,const u8 * in_key,unsigned int key_len)21 static int cbc_aes_nx_set_key(struct crypto_skcipher *tfm,
22 const u8 *in_key,
23 unsigned int key_len)
24 {
25 struct nx_crypto_ctx *nx_ctx = crypto_skcipher_ctx(tfm);
26 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
27
28 nx_ctx_init(nx_ctx, HCOP_FC_AES);
29
30 switch (key_len) {
31 case AES_KEYSIZE_128:
32 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_128);
33 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_128];
34 break;
35 case AES_KEYSIZE_192:
36 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_192);
37 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_192];
38 break;
39 case AES_KEYSIZE_256:
40 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_256);
41 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_256];
42 break;
43 default:
44 return -EINVAL;
45 }
46
47 csbcpb->cpb.hdr.mode = NX_MODE_AES_CBC;
48 memcpy(csbcpb->cpb.aes_cbc.key, in_key, key_len);
49
50 return 0;
51 }
52
cbc_aes_nx_crypt(struct skcipher_request * req,int enc)53 static int cbc_aes_nx_crypt(struct skcipher_request *req,
54 int enc)
55 {
56 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
57 struct nx_crypto_ctx *nx_ctx = crypto_skcipher_ctx(tfm);
58 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
59 unsigned long irq_flags;
60 unsigned int processed = 0, to_process;
61 int rc;
62
63 spin_lock_irqsave(&nx_ctx->lock, irq_flags);
64
65 if (enc)
66 NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT;
67 else
68 NX_CPB_FDM(csbcpb) &= ~NX_FDM_ENDE_ENCRYPT;
69
70 do {
71 to_process = req->cryptlen - processed;
72
73 rc = nx_build_sg_lists(nx_ctx, req->iv, req->dst, req->src,
74 &to_process, processed,
75 csbcpb->cpb.aes_cbc.iv);
76 if (rc)
77 goto out;
78
79 if (!nx_ctx->op.inlen || !nx_ctx->op.outlen) {
80 rc = -EINVAL;
81 goto out;
82 }
83
84 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
85 req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
86 if (rc)
87 goto out;
88
89 memcpy(req->iv, csbcpb->cpb.aes_cbc.cv, AES_BLOCK_SIZE);
90 atomic_inc(&(nx_ctx->stats->aes_ops));
91 atomic64_add(be32_to_cpu(csbcpb->csb.processed_byte_count),
92 &(nx_ctx->stats->aes_bytes));
93
94 processed += to_process;
95 } while (processed < req->cryptlen);
96 out:
97 spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
98 return rc;
99 }
100
cbc_aes_nx_encrypt(struct skcipher_request * req)101 static int cbc_aes_nx_encrypt(struct skcipher_request *req)
102 {
103 return cbc_aes_nx_crypt(req, 1);
104 }
105
cbc_aes_nx_decrypt(struct skcipher_request * req)106 static int cbc_aes_nx_decrypt(struct skcipher_request *req)
107 {
108 return cbc_aes_nx_crypt(req, 0);
109 }
110
111 struct skcipher_alg nx_cbc_aes_alg = {
112 .base.cra_name = "cbc(aes)",
113 .base.cra_driver_name = "cbc-aes-nx",
114 .base.cra_priority = 300,
115 .base.cra_blocksize = AES_BLOCK_SIZE,
116 .base.cra_ctxsize = sizeof(struct nx_crypto_ctx),
117 .base.cra_alignmask = 0xf,
118 .base.cra_module = THIS_MODULE,
119 .init = nx_crypto_ctx_aes_cbc_init,
120 .exit = nx_crypto_ctx_skcipher_exit,
121 .min_keysize = AES_MIN_KEY_SIZE,
122 .max_keysize = AES_MAX_KEY_SIZE,
123 .ivsize = AES_BLOCK_SIZE,
124 .setkey = cbc_aes_nx_set_key,
125 .encrypt = cbc_aes_nx_encrypt,
126 .decrypt = cbc_aes_nx_decrypt,
127 };
128