1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * AES CTR 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/ctr.h>
12#include <crypto/algapi.h>
13#include <linux/module.h>
14#include <linux/types.h>
15#include <linux/crypto.h>
16#include <asm/vio.h>
17
18#include "nx_csbcpb.h"
19#include "nx.h"
20
21
22static int ctr_aes_nx_set_key(struct crypto_skcipher *tfm,
23 const u8 *in_key,
24 unsigned int key_len)
25{
26 struct nx_crypto_ctx *nx_ctx = crypto_skcipher_ctx(tfm);
27 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
28
29 nx_ctx_init(nx_ctx, HCOP_FC_AES);
30
31 switch (key_len) {
32 case AES_KEYSIZE_128:
33 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_128);
34 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_128];
35 break;
36 case AES_KEYSIZE_192:
37 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_192);
38 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_192];
39 break;
40 case AES_KEYSIZE_256:
41 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_256);
42 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_256];
43 break;
44 default:
45 return -EINVAL;
46 }
47
48 csbcpb->cpb.hdr.mode = NX_MODE_AES_CTR;
49 memcpy(csbcpb->cpb.aes_ctr.key, in_key, key_len);
50
51 return 0;
52}
53
54static int ctr3686_aes_nx_set_key(struct crypto_skcipher *tfm,
55 const u8 *in_key,
56 unsigned int key_len)
57{
58 struct nx_crypto_ctx *nx_ctx = crypto_skcipher_ctx(tfm);
59
60 if (key_len < CTR_RFC3686_NONCE_SIZE)
61 return -EINVAL;
62
63 memcpy(nx_ctx->priv.ctr.nonce,
64 in_key + key_len - CTR_RFC3686_NONCE_SIZE,
65 CTR_RFC3686_NONCE_SIZE);
66
67 key_len -= CTR_RFC3686_NONCE_SIZE;
68
69 return ctr_aes_nx_set_key(tfm, in_key, key_len);
70}
71
72static int ctr_aes_nx_crypt(struct skcipher_request *req, u8 *iv)
73{
74 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
75 struct nx_crypto_ctx *nx_ctx = crypto_skcipher_ctx(tfm);
76 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
77 unsigned long irq_flags;
78 unsigned int processed = 0, to_process;
79 int rc;
80
81 spin_lock_irqsave(&nx_ctx->lock, irq_flags);
82
83 do {
84 to_process = req->cryptlen - processed;
85
86 rc = nx_build_sg_lists(nx_ctx, iv, dst: req->dst, src: req->src,
87 nbytes: &to_process, offset: processed,
88 oiv: csbcpb->cpb.aes_ctr.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(ctx: nx_ctx, op: &nx_ctx->op,
98 may_sleep: req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
99 if (rc)
100 goto out;
101
102 memcpy(iv, csbcpb->cpb.aes_cbc.cv, AES_BLOCK_SIZE);
103
104 atomic_inc(v: &(nx_ctx->stats->aes_ops));
105 atomic64_add(be32_to_cpu(csbcpb->csb.processed_byte_count),
106 v: &(nx_ctx->stats->aes_bytes));
107
108 processed += to_process;
109 } while (processed < req->cryptlen);
110out:
111 spin_unlock_irqrestore(lock: &nx_ctx->lock, flags: irq_flags);
112 return rc;
113}
114
115static int ctr3686_aes_nx_crypt(struct skcipher_request *req)
116{
117 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
118 struct nx_crypto_ctx *nx_ctx = crypto_skcipher_ctx(tfm);
119 u8 iv[16];
120
121 memcpy(iv, nx_ctx->priv.ctr.nonce, CTR_RFC3686_NONCE_SIZE);
122 memcpy(iv + CTR_RFC3686_NONCE_SIZE, req->iv, CTR_RFC3686_IV_SIZE);
123 iv[12] = iv[13] = iv[14] = 0;
124 iv[15] = 1;
125
126 return ctr_aes_nx_crypt(req, iv);
127}
128
129struct skcipher_alg nx_ctr3686_aes_alg = {
130 .base.cra_name = "rfc3686(ctr(aes))",
131 .base.cra_driver_name = "rfc3686-ctr-aes-nx",
132 .base.cra_priority = 300,
133 .base.cra_blocksize = 1,
134 .base.cra_ctxsize = sizeof(struct nx_crypto_ctx),
135 .base.cra_module = THIS_MODULE,
136 .init = nx_crypto_ctx_aes_ctr_init,
137 .exit = nx_crypto_ctx_skcipher_exit,
138 .min_keysize = AES_MIN_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
139 .max_keysize = AES_MAX_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
140 .ivsize = CTR_RFC3686_IV_SIZE,
141 .setkey = ctr3686_aes_nx_set_key,
142 .encrypt = ctr3686_aes_nx_crypt,
143 .decrypt = ctr3686_aes_nx_crypt,
144 .chunksize = AES_BLOCK_SIZE,
145};
146

source code of linux/drivers/crypto/nx/nx-aes-ctr.c