1 /*
2 * FPU: Wrapper for blkcipher touching fpu
3 *
4 * Copyright (c) Intel Corp.
5 * Author: Huang Ying <ying.huang@intel.com>
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the Free
9 * Software Foundation; either version 2 of the License, or (at your option)
10 * any later version.
11 *
12 */
13
14 #include <crypto/internal/skcipher.h>
15 #include <linux/err.h>
16 #include <linux/init.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/slab.h>
20 #include <asm/fpu/api.h>
21
22 struct crypto_fpu_ctx {
23 struct crypto_skcipher *child;
24 };
25
crypto_fpu_setkey(struct crypto_skcipher * parent,const u8 * key,unsigned int keylen)26 static int crypto_fpu_setkey(struct crypto_skcipher *parent, const u8 *key,
27 unsigned int keylen)
28 {
29 struct crypto_fpu_ctx *ctx = crypto_skcipher_ctx(parent);
30 struct crypto_skcipher *child = ctx->child;
31 int err;
32
33 crypto_skcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
34 crypto_skcipher_set_flags(child, crypto_skcipher_get_flags(parent) &
35 CRYPTO_TFM_REQ_MASK);
36 err = crypto_skcipher_setkey(child, key, keylen);
37 crypto_skcipher_set_flags(parent, crypto_skcipher_get_flags(child) &
38 CRYPTO_TFM_RES_MASK);
39 return err;
40 }
41
crypto_fpu_encrypt(struct skcipher_request * req)42 static int crypto_fpu_encrypt(struct skcipher_request *req)
43 {
44 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
45 struct crypto_fpu_ctx *ctx = crypto_skcipher_ctx(tfm);
46 struct crypto_skcipher *child = ctx->child;
47 SKCIPHER_REQUEST_ON_STACK(subreq, child);
48 int err;
49
50 skcipher_request_set_tfm(subreq, child);
51 skcipher_request_set_callback(subreq, 0, NULL, NULL);
52 skcipher_request_set_crypt(subreq, req->src, req->dst, req->cryptlen,
53 req->iv);
54
55 kernel_fpu_begin();
56 err = crypto_skcipher_encrypt(subreq);
57 kernel_fpu_end();
58
59 skcipher_request_zero(subreq);
60 return err;
61 }
62
crypto_fpu_decrypt(struct skcipher_request * req)63 static int crypto_fpu_decrypt(struct skcipher_request *req)
64 {
65 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
66 struct crypto_fpu_ctx *ctx = crypto_skcipher_ctx(tfm);
67 struct crypto_skcipher *child = ctx->child;
68 SKCIPHER_REQUEST_ON_STACK(subreq, child);
69 int err;
70
71 skcipher_request_set_tfm(subreq, child);
72 skcipher_request_set_callback(subreq, 0, NULL, NULL);
73 skcipher_request_set_crypt(subreq, req->src, req->dst, req->cryptlen,
74 req->iv);
75
76 kernel_fpu_begin();
77 err = crypto_skcipher_decrypt(subreq);
78 kernel_fpu_end();
79
80 skcipher_request_zero(subreq);
81 return err;
82 }
83
crypto_fpu_init_tfm(struct crypto_skcipher * tfm)84 static int crypto_fpu_init_tfm(struct crypto_skcipher *tfm)
85 {
86 struct skcipher_instance *inst = skcipher_alg_instance(tfm);
87 struct crypto_fpu_ctx *ctx = crypto_skcipher_ctx(tfm);
88 struct crypto_skcipher_spawn *spawn;
89 struct crypto_skcipher *cipher;
90
91 spawn = skcipher_instance_ctx(inst);
92 cipher = crypto_spawn_skcipher(spawn);
93 if (IS_ERR(cipher))
94 return PTR_ERR(cipher);
95
96 ctx->child = cipher;
97
98 return 0;
99 }
100
crypto_fpu_exit_tfm(struct crypto_skcipher * tfm)101 static void crypto_fpu_exit_tfm(struct crypto_skcipher *tfm)
102 {
103 struct crypto_fpu_ctx *ctx = crypto_skcipher_ctx(tfm);
104
105 crypto_free_skcipher(ctx->child);
106 }
107
crypto_fpu_free(struct skcipher_instance * inst)108 static void crypto_fpu_free(struct skcipher_instance *inst)
109 {
110 crypto_drop_skcipher(skcipher_instance_ctx(inst));
111 kfree(inst);
112 }
113
crypto_fpu_create(struct crypto_template * tmpl,struct rtattr ** tb)114 static int crypto_fpu_create(struct crypto_template *tmpl, struct rtattr **tb)
115 {
116 struct crypto_skcipher_spawn *spawn;
117 struct skcipher_instance *inst;
118 struct crypto_attr_type *algt;
119 struct skcipher_alg *alg;
120 const char *cipher_name;
121 int err;
122
123 algt = crypto_get_attr_type(tb);
124 if (IS_ERR(algt))
125 return PTR_ERR(algt);
126
127 if ((algt->type ^ (CRYPTO_ALG_INTERNAL | CRYPTO_ALG_TYPE_SKCIPHER)) &
128 algt->mask)
129 return -EINVAL;
130
131 if (!(algt->mask & CRYPTO_ALG_INTERNAL))
132 return -EINVAL;
133
134 cipher_name = crypto_attr_alg_name(tb[1]);
135 if (IS_ERR(cipher_name))
136 return PTR_ERR(cipher_name);
137
138 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
139 if (!inst)
140 return -ENOMEM;
141
142 spawn = skcipher_instance_ctx(inst);
143
144 crypto_set_skcipher_spawn(spawn, skcipher_crypto_instance(inst));
145 err = crypto_grab_skcipher(spawn, cipher_name, CRYPTO_ALG_INTERNAL,
146 CRYPTO_ALG_INTERNAL | CRYPTO_ALG_ASYNC);
147 if (err)
148 goto out_free_inst;
149
150 alg = crypto_skcipher_spawn_alg(spawn);
151
152 err = crypto_inst_setname(skcipher_crypto_instance(inst), "fpu",
153 &alg->base);
154 if (err)
155 goto out_drop_skcipher;
156
157 inst->alg.base.cra_flags = CRYPTO_ALG_INTERNAL;
158 inst->alg.base.cra_priority = alg->base.cra_priority;
159 inst->alg.base.cra_blocksize = alg->base.cra_blocksize;
160 inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
161
162 inst->alg.ivsize = crypto_skcipher_alg_ivsize(alg);
163 inst->alg.min_keysize = crypto_skcipher_alg_min_keysize(alg);
164 inst->alg.max_keysize = crypto_skcipher_alg_max_keysize(alg);
165
166 inst->alg.base.cra_ctxsize = sizeof(struct crypto_fpu_ctx);
167
168 inst->alg.init = crypto_fpu_init_tfm;
169 inst->alg.exit = crypto_fpu_exit_tfm;
170
171 inst->alg.setkey = crypto_fpu_setkey;
172 inst->alg.encrypt = crypto_fpu_encrypt;
173 inst->alg.decrypt = crypto_fpu_decrypt;
174
175 inst->free = crypto_fpu_free;
176
177 err = skcipher_register_instance(tmpl, inst);
178 if (err)
179 goto out_drop_skcipher;
180
181 out:
182 return err;
183
184 out_drop_skcipher:
185 crypto_drop_skcipher(spawn);
186 out_free_inst:
187 kfree(inst);
188 goto out;
189 }
190
191 static struct crypto_template crypto_fpu_tmpl = {
192 .name = "fpu",
193 .create = crypto_fpu_create,
194 .module = THIS_MODULE,
195 };
196
crypto_fpu_init(void)197 int __init crypto_fpu_init(void)
198 {
199 return crypto_register_template(&crypto_fpu_tmpl);
200 }
201
crypto_fpu_exit(void)202 void crypto_fpu_exit(void)
203 {
204 crypto_unregister_template(&crypto_fpu_tmpl);
205 }
206
207 MODULE_ALIAS_CRYPTO("fpu");
208
