1*10930333SDanny Tsen // SPDX-License-Identifier: GPL-2.0-only
2*10930333SDanny Tsen /*
3*10930333SDanny Tsen * AES CBC routines supporting VMX instructions on the Power 8
4*10930333SDanny Tsen *
5*10930333SDanny Tsen * Copyright (C) 2015 International Business Machines Inc.
6*10930333SDanny Tsen *
7*10930333SDanny Tsen * Author: Marcelo Henrique Cerri <mhcerri@br.ibm.com>
8*10930333SDanny Tsen */
9*10930333SDanny Tsen
10*10930333SDanny Tsen #include <asm/simd.h>
11*10930333SDanny Tsen #include <asm/switch_to.h>
12*10930333SDanny Tsen #include <crypto/aes.h>
13*10930333SDanny Tsen #include <crypto/internal/simd.h>
14*10930333SDanny Tsen #include <crypto/internal/skcipher.h>
15*10930333SDanny Tsen
16*10930333SDanny Tsen #include "aesp8-ppc.h"
17*10930333SDanny Tsen
18*10930333SDanny Tsen struct p8_aes_cbc_ctx {
19*10930333SDanny Tsen struct crypto_skcipher *fallback;
20*10930333SDanny Tsen struct aes_key enc_key;
21*10930333SDanny Tsen struct aes_key dec_key;
22*10930333SDanny Tsen };
23*10930333SDanny Tsen
p8_aes_cbc_init(struct crypto_skcipher * tfm)24*10930333SDanny Tsen static int p8_aes_cbc_init(struct crypto_skcipher *tfm)
25*10930333SDanny Tsen {
26*10930333SDanny Tsen struct p8_aes_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
27*10930333SDanny Tsen struct crypto_skcipher *fallback;
28*10930333SDanny Tsen
29*10930333SDanny Tsen fallback = crypto_alloc_skcipher("cbc(aes)", 0,
30*10930333SDanny Tsen CRYPTO_ALG_NEED_FALLBACK |
31*10930333SDanny Tsen CRYPTO_ALG_ASYNC);
32*10930333SDanny Tsen if (IS_ERR(fallback)) {
33*10930333SDanny Tsen pr_err("Failed to allocate cbc(aes) fallback: %ld\n",
34*10930333SDanny Tsen PTR_ERR(fallback));
35*10930333SDanny Tsen return PTR_ERR(fallback);
36*10930333SDanny Tsen }
37*10930333SDanny Tsen
38*10930333SDanny Tsen crypto_skcipher_set_reqsize(tfm, sizeof(struct skcipher_request) +
39*10930333SDanny Tsen crypto_skcipher_reqsize(fallback));
40*10930333SDanny Tsen ctx->fallback = fallback;
41*10930333SDanny Tsen return 0;
42*10930333SDanny Tsen }
43*10930333SDanny Tsen
p8_aes_cbc_exit(struct crypto_skcipher * tfm)44*10930333SDanny Tsen static void p8_aes_cbc_exit(struct crypto_skcipher *tfm)
45*10930333SDanny Tsen {
46*10930333SDanny Tsen struct p8_aes_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
47*10930333SDanny Tsen
48*10930333SDanny Tsen crypto_free_skcipher(ctx->fallback);
49*10930333SDanny Tsen }
50*10930333SDanny Tsen
p8_aes_cbc_setkey(struct crypto_skcipher * tfm,const u8 * key,unsigned int keylen)51*10930333SDanny Tsen static int p8_aes_cbc_setkey(struct crypto_skcipher *tfm, const u8 *key,
52*10930333SDanny Tsen unsigned int keylen)
53*10930333SDanny Tsen {
54*10930333SDanny Tsen struct p8_aes_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
55*10930333SDanny Tsen int ret;
56*10930333SDanny Tsen
57*10930333SDanny Tsen preempt_disable();
58*10930333SDanny Tsen pagefault_disable();
59*10930333SDanny Tsen enable_kernel_vsx();
60*10930333SDanny Tsen ret = aes_p8_set_encrypt_key(key, keylen * 8, &ctx->enc_key);
61*10930333SDanny Tsen ret |= aes_p8_set_decrypt_key(key, keylen * 8, &ctx->dec_key);
62*10930333SDanny Tsen disable_kernel_vsx();
63*10930333SDanny Tsen pagefault_enable();
64*10930333SDanny Tsen preempt_enable();
65*10930333SDanny Tsen
66*10930333SDanny Tsen ret |= crypto_skcipher_setkey(ctx->fallback, key, keylen);
67*10930333SDanny Tsen
68*10930333SDanny Tsen return ret ? -EINVAL : 0;
69*10930333SDanny Tsen }
70*10930333SDanny Tsen
p8_aes_cbc_crypt(struct skcipher_request * req,int enc)71*10930333SDanny Tsen static int p8_aes_cbc_crypt(struct skcipher_request *req, int enc)
72*10930333SDanny Tsen {
73*10930333SDanny Tsen struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
74*10930333SDanny Tsen const struct p8_aes_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
75*10930333SDanny Tsen struct skcipher_walk walk;
76*10930333SDanny Tsen unsigned int nbytes;
77*10930333SDanny Tsen int ret;
78*10930333SDanny Tsen
79*10930333SDanny Tsen if (!crypto_simd_usable()) {
80*10930333SDanny Tsen struct skcipher_request *subreq = skcipher_request_ctx(req);
81*10930333SDanny Tsen
82*10930333SDanny Tsen *subreq = *req;
83*10930333SDanny Tsen skcipher_request_set_tfm(subreq, ctx->fallback);
84*10930333SDanny Tsen return enc ? crypto_skcipher_encrypt(subreq) :
85*10930333SDanny Tsen crypto_skcipher_decrypt(subreq);
86*10930333SDanny Tsen }
87*10930333SDanny Tsen
88*10930333SDanny Tsen ret = skcipher_walk_virt(&walk, req, false);
89*10930333SDanny Tsen while ((nbytes = walk.nbytes) != 0) {
90*10930333SDanny Tsen preempt_disable();
91*10930333SDanny Tsen pagefault_disable();
92*10930333SDanny Tsen enable_kernel_vsx();
93*10930333SDanny Tsen aes_p8_cbc_encrypt(walk.src.virt.addr,
94*10930333SDanny Tsen walk.dst.virt.addr,
95*10930333SDanny Tsen round_down(nbytes, AES_BLOCK_SIZE),
96*10930333SDanny Tsen enc ? &ctx->enc_key : &ctx->dec_key,
97*10930333SDanny Tsen walk.iv, enc);
98*10930333SDanny Tsen disable_kernel_vsx();
99*10930333SDanny Tsen pagefault_enable();
100*10930333SDanny Tsen preempt_enable();
101*10930333SDanny Tsen
102*10930333SDanny Tsen ret = skcipher_walk_done(&walk, nbytes % AES_BLOCK_SIZE);
103*10930333SDanny Tsen }
104*10930333SDanny Tsen return ret;
105*10930333SDanny Tsen }
106*10930333SDanny Tsen
p8_aes_cbc_encrypt(struct skcipher_request * req)107*10930333SDanny Tsen static int p8_aes_cbc_encrypt(struct skcipher_request *req)
108*10930333SDanny Tsen {
109*10930333SDanny Tsen return p8_aes_cbc_crypt(req, 1);
110*10930333SDanny Tsen }
111*10930333SDanny Tsen
p8_aes_cbc_decrypt(struct skcipher_request * req)112*10930333SDanny Tsen static int p8_aes_cbc_decrypt(struct skcipher_request *req)
113*10930333SDanny Tsen {
114*10930333SDanny Tsen return p8_aes_cbc_crypt(req, 0);
115*10930333SDanny Tsen }
116*10930333SDanny Tsen
117*10930333SDanny Tsen struct skcipher_alg p8_aes_cbc_alg = {
118*10930333SDanny Tsen .base.cra_name = "cbc(aes)",
119*10930333SDanny Tsen .base.cra_driver_name = "p8_aes_cbc",
120*10930333SDanny Tsen .base.cra_module = THIS_MODULE,
121*10930333SDanny Tsen .base.cra_priority = 2000,
122*10930333SDanny Tsen .base.cra_flags = CRYPTO_ALG_NEED_FALLBACK,
123*10930333SDanny Tsen .base.cra_blocksize = AES_BLOCK_SIZE,
124*10930333SDanny Tsen .base.cra_ctxsize = sizeof(struct p8_aes_cbc_ctx),
125*10930333SDanny Tsen .setkey = p8_aes_cbc_setkey,
126*10930333SDanny Tsen .encrypt = p8_aes_cbc_encrypt,
127*10930333SDanny Tsen .decrypt = p8_aes_cbc_decrypt,
128*10930333SDanny Tsen .init = p8_aes_cbc_init,
129*10930333SDanny Tsen .exit = p8_aes_cbc_exit,
130*10930333SDanny Tsen .min_keysize = AES_MIN_KEY_SIZE,
131*10930333SDanny Tsen .max_keysize = AES_MAX_KEY_SIZE,
132*10930333SDanny Tsen .ivsize = AES_BLOCK_SIZE,
133*10930333SDanny Tsen };
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