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Herbert Xu124b53d2007-04-16 20:49:20 +10001/*
2 * Software async crypto daemon.
3 *
4 * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the Free
8 * Software Foundation; either version 2 of the License, or (at your option)
9 * any later version.
10 *
11 */
12
13#include <crypto/algapi.h>
14#include <linux/err.h>
15#include <linux/init.h>
16#include <linux/kernel.h>
17#include <linux/kthread.h>
18#include <linux/list.h>
19#include <linux/module.h>
20#include <linux/mutex.h>
21#include <linux/scatterlist.h>
22#include <linux/sched.h>
23#include <linux/slab.h>
24#include <linux/spinlock.h>
25
26#define CRYPTD_MAX_QLEN 100
27
28struct cryptd_state {
29 spinlock_t lock;
30 struct mutex mutex;
31 struct crypto_queue queue;
32 struct task_struct *task;
33};
34
35struct cryptd_instance_ctx {
36 struct crypto_spawn spawn;
37 struct cryptd_state *state;
38};
39
40struct cryptd_blkcipher_ctx {
41 struct crypto_blkcipher *child;
42};
43
44struct cryptd_blkcipher_request_ctx {
45 crypto_completion_t complete;
46};
47
48
49static inline struct cryptd_state *cryptd_get_state(struct crypto_tfm *tfm)
50{
51 struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);
52 struct cryptd_instance_ctx *ictx = crypto_instance_ctx(inst);
53 return ictx->state;
54}
55
56static int cryptd_blkcipher_setkey(struct crypto_ablkcipher *parent,
57 const u8 *key, unsigned int keylen)
58{
59 struct cryptd_blkcipher_ctx *ctx = crypto_ablkcipher_ctx(parent);
60 struct crypto_blkcipher *child = ctx->child;
61 int err;
62
63 crypto_blkcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
64 crypto_blkcipher_set_flags(child, crypto_ablkcipher_get_flags(parent) &
65 CRYPTO_TFM_REQ_MASK);
66 err = crypto_blkcipher_setkey(child, key, keylen);
67 crypto_ablkcipher_set_flags(parent, crypto_blkcipher_get_flags(child) &
68 CRYPTO_TFM_RES_MASK);
69 return err;
70}
71
72static void cryptd_blkcipher_crypt(struct ablkcipher_request *req,
73 struct crypto_blkcipher *child,
74 int err,
75 int (*crypt)(struct blkcipher_desc *desc,
76 struct scatterlist *dst,
77 struct scatterlist *src,
78 unsigned int len))
79{
80 struct cryptd_blkcipher_request_ctx *rctx;
81 struct blkcipher_desc desc;
82
83 rctx = ablkcipher_request_ctx(req);
84
85 if (unlikely(err == -EINPROGRESS)) {
86 rctx->complete(&req->base, err);
87 return;
88 }
89
90 desc.tfm = child;
91 desc.info = req->info;
92 desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
93
94 err = crypt(&desc, req->dst, req->src, req->nbytes);
95
96 req->base.complete = rctx->complete;
97
98 local_bh_disable();
99 req->base.complete(&req->base, err);
100 local_bh_enable();
101}
102
103static void cryptd_blkcipher_encrypt(struct crypto_async_request *req, int err)
104{
105 struct cryptd_blkcipher_ctx *ctx = crypto_tfm_ctx(req->tfm);
106 struct crypto_blkcipher *child = ctx->child;
107
108 cryptd_blkcipher_crypt(ablkcipher_request_cast(req), child, err,
109 crypto_blkcipher_crt(child)->encrypt);
110}
111
112static void cryptd_blkcipher_decrypt(struct crypto_async_request *req, int err)
113{
114 struct cryptd_blkcipher_ctx *ctx = crypto_tfm_ctx(req->tfm);
115 struct crypto_blkcipher *child = ctx->child;
116
117 cryptd_blkcipher_crypt(ablkcipher_request_cast(req), child, err,
118 crypto_blkcipher_crt(child)->decrypt);
119}
120
121static int cryptd_blkcipher_enqueue(struct ablkcipher_request *req,
122 crypto_completion_t complete)
123{
124 struct cryptd_blkcipher_request_ctx *rctx = ablkcipher_request_ctx(req);
125 struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
126 struct cryptd_state *state =
127 cryptd_get_state(crypto_ablkcipher_tfm(tfm));
128 int err;
129
130 rctx->complete = req->base.complete;
131 req->base.complete = complete;
132
133 spin_lock_bh(&state->lock);
Herbert Xu2de98e72007-08-26 19:12:47 +0800134 err = ablkcipher_enqueue_request(&state->queue, req);
Herbert Xu124b53d2007-04-16 20:49:20 +1000135 spin_unlock_bh(&state->lock);
136
137 wake_up_process(state->task);
138 return err;
139}
140
141static int cryptd_blkcipher_encrypt_enqueue(struct ablkcipher_request *req)
142{
143 return cryptd_blkcipher_enqueue(req, cryptd_blkcipher_encrypt);
144}
145
146static int cryptd_blkcipher_decrypt_enqueue(struct ablkcipher_request *req)
147{
148 return cryptd_blkcipher_enqueue(req, cryptd_blkcipher_decrypt);
149}
150
151static int cryptd_blkcipher_init_tfm(struct crypto_tfm *tfm)
152{
153 struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);
154 struct cryptd_instance_ctx *ictx = crypto_instance_ctx(inst);
155 struct crypto_spawn *spawn = &ictx->spawn;
156 struct cryptd_blkcipher_ctx *ctx = crypto_tfm_ctx(tfm);
157 struct crypto_blkcipher *cipher;
158
159 cipher = crypto_spawn_blkcipher(spawn);
160 if (IS_ERR(cipher))
161 return PTR_ERR(cipher);
162
163 ctx->child = cipher;
164 tfm->crt_ablkcipher.reqsize =
165 sizeof(struct cryptd_blkcipher_request_ctx);
166 return 0;
167}
168
169static void cryptd_blkcipher_exit_tfm(struct crypto_tfm *tfm)
170{
171 struct cryptd_blkcipher_ctx *ctx = crypto_tfm_ctx(tfm);
172 struct cryptd_state *state = cryptd_get_state(tfm);
173 int active;
174
175 mutex_lock(&state->mutex);
Herbert Xu2de98e72007-08-26 19:12:47 +0800176 active = ablkcipher_tfm_in_queue(&state->queue,
177 __crypto_ablkcipher_cast(tfm));
Herbert Xu124b53d2007-04-16 20:49:20 +1000178 mutex_unlock(&state->mutex);
179
180 BUG_ON(active);
181
182 crypto_free_blkcipher(ctx->child);
183}
184
185static struct crypto_instance *cryptd_alloc_instance(struct crypto_alg *alg,
186 struct cryptd_state *state)
187{
188 struct crypto_instance *inst;
189 struct cryptd_instance_ctx *ctx;
190 int err;
191
192 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
193 if (IS_ERR(inst))
194 goto out;
195
196 err = -ENAMETOOLONG;
197 if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
198 "cryptd(%s)", alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
199 goto out_free_inst;
200
201 ctx = crypto_instance_ctx(inst);
202 err = crypto_init_spawn(&ctx->spawn, alg, inst,
203 CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_ASYNC);
204 if (err)
205 goto out_free_inst;
206
207 ctx->state = state;
208
209 memcpy(inst->alg.cra_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
210
211 inst->alg.cra_priority = alg->cra_priority + 50;
212 inst->alg.cra_blocksize = alg->cra_blocksize;
213 inst->alg.cra_alignmask = alg->cra_alignmask;
214
215out:
216 return inst;
217
218out_free_inst:
219 kfree(inst);
220 inst = ERR_PTR(err);
221 goto out;
222}
223
224static struct crypto_instance *cryptd_alloc_blkcipher(
225 struct rtattr **tb, struct cryptd_state *state)
226{
227 struct crypto_instance *inst;
228 struct crypto_alg *alg;
229
230 alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_BLKCIPHER,
Herbert Xu332f88402007-11-15 22:36:07 +0800231 CRYPTO_ALG_TYPE_MASK);
Herbert Xu124b53d2007-04-16 20:49:20 +1000232 if (IS_ERR(alg))
233 return ERR_PTR(PTR_ERR(alg));
234
235 inst = cryptd_alloc_instance(alg, state);
236 if (IS_ERR(inst))
237 goto out_put_alg;
238
Herbert Xu332f88402007-11-15 22:36:07 +0800239 inst->alg.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC;
Herbert Xu124b53d2007-04-16 20:49:20 +1000240 inst->alg.cra_type = &crypto_ablkcipher_type;
241
242 inst->alg.cra_ablkcipher.ivsize = alg->cra_blkcipher.ivsize;
243 inst->alg.cra_ablkcipher.min_keysize = alg->cra_blkcipher.min_keysize;
244 inst->alg.cra_ablkcipher.max_keysize = alg->cra_blkcipher.max_keysize;
245
Herbert Xu927eead2007-11-27 21:15:31 +0800246 inst->alg.cra_ablkcipher.geniv = alg->cra_blkcipher.geniv;
247
Herbert Xu124b53d2007-04-16 20:49:20 +1000248 inst->alg.cra_ctxsize = sizeof(struct cryptd_blkcipher_ctx);
249
250 inst->alg.cra_init = cryptd_blkcipher_init_tfm;
251 inst->alg.cra_exit = cryptd_blkcipher_exit_tfm;
252
253 inst->alg.cra_ablkcipher.setkey = cryptd_blkcipher_setkey;
254 inst->alg.cra_ablkcipher.encrypt = cryptd_blkcipher_encrypt_enqueue;
255 inst->alg.cra_ablkcipher.decrypt = cryptd_blkcipher_decrypt_enqueue;
256
Herbert Xu124b53d2007-04-16 20:49:20 +1000257out_put_alg:
258 crypto_mod_put(alg);
259 return inst;
260}
261
262static struct cryptd_state state;
263
264static struct crypto_instance *cryptd_alloc(struct rtattr **tb)
265{
266 struct crypto_attr_type *algt;
267
268 algt = crypto_get_attr_type(tb);
269 if (IS_ERR(algt))
270 return ERR_PTR(PTR_ERR(algt));
271
272 switch (algt->type & algt->mask & CRYPTO_ALG_TYPE_MASK) {
273 case CRYPTO_ALG_TYPE_BLKCIPHER:
274 return cryptd_alloc_blkcipher(tb, &state);
275 }
276
277 return ERR_PTR(-EINVAL);
278}
279
280static void cryptd_free(struct crypto_instance *inst)
281{
282 struct cryptd_instance_ctx *ctx = crypto_instance_ctx(inst);
283
284 crypto_drop_spawn(&ctx->spawn);
285 kfree(inst);
286}
287
288static struct crypto_template cryptd_tmpl = {
289 .name = "cryptd",
290 .alloc = cryptd_alloc,
291 .free = cryptd_free,
292 .module = THIS_MODULE,
293};
294
295static inline int cryptd_create_thread(struct cryptd_state *state,
296 int (*fn)(void *data), const char *name)
297{
298 spin_lock_init(&state->lock);
299 mutex_init(&state->mutex);
300 crypto_init_queue(&state->queue, CRYPTD_MAX_QLEN);
301
Rafael J. Wysocki189fe312007-05-31 18:10:22 +1000302 state->task = kthread_run(fn, state, name);
Herbert Xu124b53d2007-04-16 20:49:20 +1000303 if (IS_ERR(state->task))
304 return PTR_ERR(state->task);
305
306 return 0;
307}
308
309static inline void cryptd_stop_thread(struct cryptd_state *state)
310{
311 BUG_ON(state->queue.qlen);
312 kthread_stop(state->task);
313}
314
315static int cryptd_thread(void *data)
316{
317 struct cryptd_state *state = data;
318 int stop;
319
Rafael J. Wysocki189fe312007-05-31 18:10:22 +1000320 current->flags |= PF_NOFREEZE;
321
Herbert Xu124b53d2007-04-16 20:49:20 +1000322 do {
323 struct crypto_async_request *req, *backlog;
324
325 mutex_lock(&state->mutex);
326 __set_current_state(TASK_INTERRUPTIBLE);
327
328 spin_lock_bh(&state->lock);
329 backlog = crypto_get_backlog(&state->queue);
330 req = crypto_dequeue_request(&state->queue);
331 spin_unlock_bh(&state->lock);
332
333 stop = kthread_should_stop();
334
335 if (stop || req) {
336 __set_current_state(TASK_RUNNING);
337 if (req) {
338 if (backlog)
339 backlog->complete(backlog,
340 -EINPROGRESS);
341 req->complete(req, 0);
342 }
343 }
344
345 mutex_unlock(&state->mutex);
346
347 schedule();
348 } while (!stop);
349
350 return 0;
351}
352
353static int __init cryptd_init(void)
354{
355 int err;
356
357 err = cryptd_create_thread(&state, cryptd_thread, "cryptd");
358 if (err)
359 return err;
360
361 err = crypto_register_template(&cryptd_tmpl);
362 if (err)
363 kthread_stop(state.task);
364
365 return err;
366}
367
368static void __exit cryptd_exit(void)
369{
370 cryptd_stop_thread(&state);
371 crypto_unregister_template(&cryptd_tmpl);
372}
373
374module_init(cryptd_init);
375module_exit(cryptd_exit);
376
377MODULE_LICENSE("GPL");
378MODULE_DESCRIPTION("Software async crypto daemon");