diff options
Diffstat (limited to 'crypto/cryptd.c')
| -rw-r--r-- | crypto/cryptd.c | 375 |
1 files changed, 375 insertions, 0 deletions
diff --git a/crypto/cryptd.c b/crypto/cryptd.c new file mode 100644 index 000000000000..3ff4e1f0f032 --- /dev/null +++ b/crypto/cryptd.c @@ -0,0 +1,375 @@ +/* + * Software async crypto daemon. + * + * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the Free + * Software Foundation; either version 2 of the License, or (at your option) + * any later version. + * + */ + +#include <crypto/algapi.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/kthread.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/scatterlist.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/spinlock.h> + +#define CRYPTD_MAX_QLEN 100 + +struct cryptd_state { + spinlock_t lock; + struct mutex mutex; + struct crypto_queue queue; + struct task_struct *task; +}; + +struct cryptd_instance_ctx { + struct crypto_spawn spawn; + struct cryptd_state *state; +}; + +struct cryptd_blkcipher_ctx { + struct crypto_blkcipher *child; +}; + +struct cryptd_blkcipher_request_ctx { + crypto_completion_t complete; +}; + + +static inline struct cryptd_state *cryptd_get_state(struct crypto_tfm *tfm) +{ + struct crypto_instance *inst = crypto_tfm_alg_instance(tfm); + struct cryptd_instance_ctx *ictx = crypto_instance_ctx(inst); + return ictx->state; +} + +static int cryptd_blkcipher_setkey(struct crypto_ablkcipher *parent, + const u8 *key, unsigned int keylen) +{ + struct cryptd_blkcipher_ctx *ctx = crypto_ablkcipher_ctx(parent); + struct crypto_blkcipher *child = ctx->child; + int err; + + crypto_blkcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK); + crypto_blkcipher_set_flags(child, crypto_ablkcipher_get_flags(parent) & + CRYPTO_TFM_REQ_MASK); + err = crypto_blkcipher_setkey(child, key, keylen); + crypto_ablkcipher_set_flags(parent, crypto_blkcipher_get_flags(child) & + CRYPTO_TFM_RES_MASK); + return err; +} + +static void cryptd_blkcipher_crypt(struct ablkcipher_request *req, + struct crypto_blkcipher *child, + int err, + int (*crypt)(struct blkcipher_desc *desc, + struct scatterlist *dst, + struct scatterlist *src, + unsigned int len)) +{ + struct cryptd_blkcipher_request_ctx *rctx; + struct blkcipher_desc desc; + + rctx = ablkcipher_request_ctx(req); + + if (unlikely(err == -EINPROGRESS)) { + rctx->complete(&req->base, err); + return; + } + + desc.tfm = child; + desc.info = req->info; + desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; + + err = crypt(&desc, req->dst, req->src, req->nbytes); + + req->base.complete = rctx->complete; + + local_bh_disable(); + req->base.complete(&req->base, err); + local_bh_enable(); +} + +static void cryptd_blkcipher_encrypt(struct crypto_async_request *req, int err) +{ + struct cryptd_blkcipher_ctx *ctx = crypto_tfm_ctx(req->tfm); + struct crypto_blkcipher *child = ctx->child; + + cryptd_blkcipher_crypt(ablkcipher_request_cast(req), child, err, + crypto_blkcipher_crt(child)->encrypt); +} + +static void cryptd_blkcipher_decrypt(struct crypto_async_request *req, int err) +{ + struct cryptd_blkcipher_ctx *ctx = crypto_tfm_ctx(req->tfm); + struct crypto_blkcipher *child = ctx->child; + + cryptd_blkcipher_crypt(ablkcipher_request_cast(req), child, err, + crypto_blkcipher_crt(child)->decrypt); +} + +static int cryptd_blkcipher_enqueue(struct ablkcipher_request *req, + crypto_completion_t complete) +{ + struct cryptd_blkcipher_request_ctx *rctx = ablkcipher_request_ctx(req); + struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req); + struct cryptd_state *state = + cryptd_get_state(crypto_ablkcipher_tfm(tfm)); + int err; + + rctx->complete = req->base.complete; + req->base.complete = complete; + + spin_lock_bh(&state->lock); + err = ablkcipher_enqueue_request(crypto_ablkcipher_alg(tfm), req); + spin_unlock_bh(&state->lock); + + wake_up_process(state->task); + return err; +} + +static int cryptd_blkcipher_encrypt_enqueue(struct ablkcipher_request *req) +{ + return cryptd_blkcipher_enqueue(req, cryptd_blkcipher_encrypt); +} + +static int cryptd_blkcipher_decrypt_enqueue(struct ablkcipher_request *req) +{ + return cryptd_blkcipher_enqueue(req, cryptd_blkcipher_decrypt); +} + +static int cryptd_blkcipher_init_tfm(struct crypto_tfm *tfm) +{ + struct crypto_instance *inst = crypto_tfm_alg_instance(tfm); + struct cryptd_instance_ctx *ictx = crypto_instance_ctx(inst); + struct crypto_spawn *spawn = &ictx->spawn; + struct cryptd_blkcipher_ctx *ctx = crypto_tfm_ctx(tfm); + struct crypto_blkcipher *cipher; + + cipher = crypto_spawn_blkcipher(spawn); + if (IS_ERR(cipher)) + return PTR_ERR(cipher); + + ctx->child = cipher; + tfm->crt_ablkcipher.reqsize = + sizeof(struct cryptd_blkcipher_request_ctx); + return 0; +} + +static void cryptd_blkcipher_exit_tfm(struct crypto_tfm *tfm) +{ + struct cryptd_blkcipher_ctx *ctx = crypto_tfm_ctx(tfm); + struct cryptd_state *state = cryptd_get_state(tfm); + int active; + + mutex_lock(&state->mutex); + active = ablkcipher_tfm_in_queue(__crypto_ablkcipher_cast(tfm)); + mutex_unlock(&state->mutex); + + BUG_ON(active); + + crypto_free_blkcipher(ctx->child); +} + +static struct crypto_instance *cryptd_alloc_instance(struct crypto_alg *alg, + struct cryptd_state *state) +{ + struct crypto_instance *inst; + struct cryptd_instance_ctx *ctx; + int err; + + inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); + if (IS_ERR(inst)) + goto out; + + err = -ENAMETOOLONG; + if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, + "cryptd(%s)", alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME) + goto out_free_inst; + + ctx = crypto_instance_ctx(inst); + err = crypto_init_spawn(&ctx->spawn, alg, inst, + CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_ASYNC); + if (err) + goto out_free_inst; + + ctx->state = state; + + memcpy(inst->alg.cra_name, alg->cra_name, CRYPTO_MAX_ALG_NAME); + + inst->alg.cra_priority = alg->cra_priority + 50; + inst->alg.cra_blocksize = alg->cra_blocksize; + inst->alg.cra_alignmask = alg->cra_alignmask; + +out: + return inst; + +out_free_inst: + kfree(inst); + inst = ERR_PTR(err); + goto out; +} + +static struct crypto_instance *cryptd_alloc_blkcipher( + struct rtattr **tb, struct cryptd_state *state) +{ + struct crypto_instance *inst; + struct crypto_alg *alg; + + alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_BLKCIPHER, + CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_ASYNC); + if (IS_ERR(alg)) + return ERR_PTR(PTR_ERR(alg)); + + inst = cryptd_alloc_instance(alg, state); + if (IS_ERR(inst)) + goto out_put_alg; + + inst->alg.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER | CRYPTO_ALG_ASYNC; + inst->alg.cra_type = &crypto_ablkcipher_type; + + inst->alg.cra_ablkcipher.ivsize = alg->cra_blkcipher.ivsize; + inst->alg.cra_ablkcipher.min_keysize = alg->cra_blkcipher.min_keysize; + inst->alg.cra_ablkcipher.max_keysize = alg->cra_blkcipher.max_keysize; + + inst->alg.cra_ctxsize = sizeof(struct cryptd_blkcipher_ctx); + + inst->alg.cra_init = cryptd_blkcipher_init_tfm; + inst->alg.cra_exit = cryptd_blkcipher_exit_tfm; + + inst->alg.cra_ablkcipher.setkey = cryptd_blkcipher_setkey; + inst->alg.cra_ablkcipher.encrypt = cryptd_blkcipher_encrypt_enqueue; + inst->alg.cra_ablkcipher.decrypt = cryptd_blkcipher_decrypt_enqueue; + + inst->alg.cra_ablkcipher.queue = &state->queue; + +out_put_alg: + crypto_mod_put(alg); + return inst; +} + +static struct cryptd_state state; + +static struct crypto_instance *cryptd_alloc(struct rtattr **tb) +{ + struct crypto_attr_type *algt; + + algt = crypto_get_attr_type(tb); + if (IS_ERR(algt)) + return ERR_PTR(PTR_ERR(algt)); + + switch (algt->type & algt->mask & CRYPTO_ALG_TYPE_MASK) { + case CRYPTO_ALG_TYPE_BLKCIPHER: + return cryptd_alloc_blkcipher(tb, &state); + } + + return ERR_PTR(-EINVAL); +} + +static void cryptd_free(struct crypto_instance *inst) +{ + struct cryptd_instance_ctx *ctx = crypto_instance_ctx(inst); + + crypto_drop_spawn(&ctx->spawn); + kfree(inst); +} + +static struct crypto_template cryptd_tmpl = { + .name = "cryptd", + .alloc = cryptd_alloc, + .free = cryptd_free, + .module = THIS_MODULE, +}; + +static inline int cryptd_create_thread(struct cryptd_state *state, + int (*fn)(void *data), const char *name) +{ + spin_lock_init(&state->lock); + mutex_init(&state->mutex); + crypto_init_queue(&state->queue, CRYPTD_MAX_QLEN); + + state->task = kthread_create(fn, state, name); + if (IS_ERR(state->task)) + return PTR_ERR(state->task); + + return 0; +} + +static inline void cryptd_stop_thread(struct cryptd_state *state) +{ + BUG_ON(state->queue.qlen); + kthread_stop(state->task); +} + +static int cryptd_thread(void *data) +{ + struct cryptd_state *state = data; + int stop; + + do { + struct crypto_async_request *req, *backlog; + + mutex_lock(&state->mutex); + __set_current_state(TASK_INTERRUPTIBLE); + + spin_lock_bh(&state->lock); + backlog = crypto_get_backlog(&state->queue); + req = crypto_dequeue_request(&state->queue); + spin_unlock_bh(&state->lock); + + stop = kthread_should_stop(); + + if (stop || req) { + __set_current_state(TASK_RUNNING); + if (req) { + if (backlog) + backlog->complete(backlog, + -EINPROGRESS); + req->complete(req, 0); + } + } + + mutex_unlock(&state->mutex); + + schedule(); + } while (!stop); + + return 0; +} + +static int __init cryptd_init(void) +{ + int err; + + err = cryptd_create_thread(&state, cryptd_thread, "cryptd"); + if (err) + return err; + + err = crypto_register_template(&cryptd_tmpl); + if (err) + kthread_stop(state.task); + + return err; +} + +static void __exit cryptd_exit(void) +{ + cryptd_stop_thread(&state); + crypto_unregister_template(&cryptd_tmpl); +} + +module_init(cryptd_init); +module_exit(cryptd_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Software async crypto daemon"); |
