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14#include <crypto/algapi.h>
15#include <linux/err.h>
16#include <linux/init.h>
17#include <linux/kernel.h>
18#include <linux/module.h>
19#include <asm/i387.h>
20
21struct crypto_fpu_ctx {
22 struct crypto_blkcipher *child;
23};
24
25static int crypto_fpu_setkey(struct crypto_tfm *parent, const u8 *key,
26 unsigned int keylen)
27{
28 struct crypto_fpu_ctx *ctx = crypto_tfm_ctx(parent);
29 struct crypto_blkcipher *child = ctx->child;
30 int err;
31
32 crypto_blkcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
33 crypto_blkcipher_set_flags(child, crypto_tfm_get_flags(parent) &
34 CRYPTO_TFM_REQ_MASK);
35 err = crypto_blkcipher_setkey(child, key, keylen);
36 crypto_tfm_set_flags(parent, crypto_blkcipher_get_flags(child) &
37 CRYPTO_TFM_RES_MASK);
38 return err;
39}
40
41static int crypto_fpu_encrypt(struct blkcipher_desc *desc_in,
42 struct scatterlist *dst, struct scatterlist *src,
43 unsigned int nbytes)
44{
45 int err;
46 struct crypto_fpu_ctx *ctx = crypto_blkcipher_ctx(desc_in->tfm);
47 struct crypto_blkcipher *child = ctx->child;
48 struct blkcipher_desc desc = {
49 .tfm = child,
50 .info = desc_in->info,
51 .flags = desc_in->flags & ~CRYPTO_TFM_REQ_MAY_SLEEP,
52 };
53
54 kernel_fpu_begin();
55 err = crypto_blkcipher_crt(desc.tfm)->encrypt(&desc, dst, src, nbytes);
56 kernel_fpu_end();
57 return err;
58}
59
60static int crypto_fpu_decrypt(struct blkcipher_desc *desc_in,
61 struct scatterlist *dst, struct scatterlist *src,
62 unsigned int nbytes)
63{
64 int err;
65 struct crypto_fpu_ctx *ctx = crypto_blkcipher_ctx(desc_in->tfm);
66 struct crypto_blkcipher *child = ctx->child;
67 struct blkcipher_desc desc = {
68 .tfm = child,
69 .info = desc_in->info,
70 .flags = desc_in->flags & ~CRYPTO_TFM_REQ_MAY_SLEEP,
71 };
72
73 kernel_fpu_begin();
74 err = crypto_blkcipher_crt(desc.tfm)->decrypt(&desc, dst, src, nbytes);
75 kernel_fpu_end();
76 return err;
77}
78
79static int crypto_fpu_init_tfm(struct crypto_tfm *tfm)
80{
81 struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);
82 struct crypto_spawn *spawn = crypto_instance_ctx(inst);
83 struct crypto_fpu_ctx *ctx = crypto_tfm_ctx(tfm);
84 struct crypto_blkcipher *cipher;
85
86 cipher = crypto_spawn_blkcipher(spawn);
87 if (IS_ERR(cipher))
88 return PTR_ERR(cipher);
89
90 ctx->child = cipher;
91 return 0;
92}
93
94static void crypto_fpu_exit_tfm(struct crypto_tfm *tfm)
95{
96 struct crypto_fpu_ctx *ctx = crypto_tfm_ctx(tfm);
97 crypto_free_blkcipher(ctx->child);
98}
99
100static struct crypto_instance *crypto_fpu_alloc(struct rtattr **tb)
101{
102 struct crypto_instance *inst;
103 struct crypto_alg *alg;
104 int err;
105
106 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_BLKCIPHER);
107 if (err)
108 return ERR_PTR(err);
109
110 alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_BLKCIPHER,
111 CRYPTO_ALG_TYPE_MASK);
112 if (IS_ERR(alg))
113 return ERR_CAST(alg);
114
115 inst = crypto_alloc_instance("fpu", alg);
116 if (IS_ERR(inst))
117 goto out_put_alg;
118
119 inst->alg.cra_flags = alg->cra_flags;
120 inst->alg.cra_priority = alg->cra_priority;
121 inst->alg.cra_blocksize = alg->cra_blocksize;
122 inst->alg.cra_alignmask = alg->cra_alignmask;
123 inst->alg.cra_type = alg->cra_type;
124 inst->alg.cra_blkcipher.ivsize = alg->cra_blkcipher.ivsize;
125 inst->alg.cra_blkcipher.min_keysize = alg->cra_blkcipher.min_keysize;
126 inst->alg.cra_blkcipher.max_keysize = alg->cra_blkcipher.max_keysize;
127 inst->alg.cra_ctxsize = sizeof(struct crypto_fpu_ctx);
128 inst->alg.cra_init = crypto_fpu_init_tfm;
129 inst->alg.cra_exit = crypto_fpu_exit_tfm;
130 inst->alg.cra_blkcipher.setkey = crypto_fpu_setkey;
131 inst->alg.cra_blkcipher.encrypt = crypto_fpu_encrypt;
132 inst->alg.cra_blkcipher.decrypt = crypto_fpu_decrypt;
133
134out_put_alg:
135 crypto_mod_put(alg);
136 return inst;
137}
138
139static void crypto_fpu_free(struct crypto_instance *inst)
140{
141 crypto_drop_spawn(crypto_instance_ctx(inst));
142 kfree(inst);
143}
144
145static struct crypto_template crypto_fpu_tmpl = {
146 .name = "fpu",
147 .alloc = crypto_fpu_alloc,
148 .free = crypto_fpu_free,
149 .module = THIS_MODULE,
150};
151
152static int __init crypto_fpu_module_init(void)
153{
154 return crypto_register_template(&crypto_fpu_tmpl);
155}
156
157static void __exit crypto_fpu_module_exit(void)
158{
159 crypto_unregister_template(&crypto_fpu_tmpl);
160}
161
162module_init(crypto_fpu_module_init);
163module_exit(crypto_fpu_module_exit);
164
165MODULE_LICENSE("GPL");
166MODULE_DESCRIPTION("FPU block cipher wrapper");
167
