diff options
Diffstat (limited to 'crypto/chainiv.c')
-rw-r--r-- | crypto/chainiv.c | 317 |
1 files changed, 0 insertions, 317 deletions
diff --git a/crypto/chainiv.c b/crypto/chainiv.c deleted file mode 100644 index b434001..0000000 --- a/crypto/chainiv.c +++ /dev/null @@ -1,317 +0,0 @@ -/* - * chainiv: Chain IV Generator - * - * Generate IVs simply be using the last block of the previous encryption. - * This is mainly useful for CBC with a synchronous algorithm. - * - * Copyright (c) 2007 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/internal/skcipher.h> -#include <crypto/rng.h> -#include <crypto/crypto_wq.h> -#include <linux/err.h> -#include <linux/init.h> -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/spinlock.h> -#include <linux/string.h> -#include <linux/workqueue.h> - -enum { - CHAINIV_STATE_INUSE = 0, -}; - -struct chainiv_ctx { - spinlock_t lock; - char iv[]; -}; - -struct async_chainiv_ctx { - unsigned long state; - - spinlock_t lock; - int err; - - struct crypto_queue queue; - struct work_struct postponed; - - char iv[]; -}; - -static int chainiv_givencrypt(struct skcipher_givcrypt_request *req) -{ - struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req); - struct chainiv_ctx *ctx = crypto_ablkcipher_ctx(geniv); - struct ablkcipher_request *subreq = skcipher_givcrypt_reqctx(req); - unsigned int ivsize; - int err; - - ablkcipher_request_set_tfm(subreq, skcipher_geniv_cipher(geniv)); - ablkcipher_request_set_callback(subreq, req->creq.base.flags & - ~CRYPTO_TFM_REQ_MAY_SLEEP, - req->creq.base.complete, - req->creq.base.data); - ablkcipher_request_set_crypt(subreq, req->creq.src, req->creq.dst, - req->creq.nbytes, req->creq.info); - - spin_lock_bh(&ctx->lock); - - ivsize = crypto_ablkcipher_ivsize(geniv); - - memcpy(req->giv, ctx->iv, ivsize); - memcpy(subreq->info, ctx->iv, ivsize); - - err = crypto_ablkcipher_encrypt(subreq); - if (err) - goto unlock; - - memcpy(ctx->iv, subreq->info, ivsize); - -unlock: - spin_unlock_bh(&ctx->lock); - - return err; -} - -static int chainiv_init_common(struct crypto_tfm *tfm, char iv[]) -{ - struct crypto_ablkcipher *geniv = __crypto_ablkcipher_cast(tfm); - int err = 0; - - tfm->crt_ablkcipher.reqsize = sizeof(struct ablkcipher_request); - - if (iv) { - err = crypto_rng_get_bytes(crypto_default_rng, iv, - crypto_ablkcipher_ivsize(geniv)); - crypto_put_default_rng(); - } - - return err ?: skcipher_geniv_init(tfm); -} - -static int chainiv_init(struct crypto_tfm *tfm) -{ - struct crypto_ablkcipher *geniv = __crypto_ablkcipher_cast(tfm); - struct chainiv_ctx *ctx = crypto_tfm_ctx(tfm); - char *iv; - - spin_lock_init(&ctx->lock); - - iv = NULL; - if (!crypto_get_default_rng()) { - crypto_ablkcipher_crt(geniv)->givencrypt = chainiv_givencrypt; - iv = ctx->iv; - } - - return chainiv_init_common(tfm, iv); -} - -static int async_chainiv_schedule_work(struct async_chainiv_ctx *ctx) -{ - int queued; - int err = ctx->err; - - if (!ctx->queue.qlen) { - smp_mb__before_atomic(); - clear_bit(CHAINIV_STATE_INUSE, &ctx->state); - - if (!ctx->queue.qlen || - test_and_set_bit(CHAINIV_STATE_INUSE, &ctx->state)) - goto out; - } - - queued = queue_work(kcrypto_wq, &ctx->postponed); - BUG_ON(!queued); - -out: - return err; -} - -static int async_chainiv_postpone_request(struct skcipher_givcrypt_request *req) -{ - struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req); - struct async_chainiv_ctx *ctx = crypto_ablkcipher_ctx(geniv); - int err; - - spin_lock_bh(&ctx->lock); - err = skcipher_enqueue_givcrypt(&ctx->queue, req); - spin_unlock_bh(&ctx->lock); - - if (test_and_set_bit(CHAINIV_STATE_INUSE, &ctx->state)) - return err; - - ctx->err = err; - return async_chainiv_schedule_work(ctx); -} - -static int async_chainiv_givencrypt_tail(struct skcipher_givcrypt_request *req) -{ - struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req); - struct async_chainiv_ctx *ctx = crypto_ablkcipher_ctx(geniv); - struct ablkcipher_request *subreq = skcipher_givcrypt_reqctx(req); - unsigned int ivsize = crypto_ablkcipher_ivsize(geniv); - - memcpy(req->giv, ctx->iv, ivsize); - memcpy(subreq->info, ctx->iv, ivsize); - - ctx->err = crypto_ablkcipher_encrypt(subreq); - if (ctx->err) - goto out; - - memcpy(ctx->iv, subreq->info, ivsize); - -out: - return async_chainiv_schedule_work(ctx); -} - -static int async_chainiv_givencrypt(struct skcipher_givcrypt_request *req) -{ - struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req); - struct async_chainiv_ctx *ctx = crypto_ablkcipher_ctx(geniv); - struct ablkcipher_request *subreq = skcipher_givcrypt_reqctx(req); - - ablkcipher_request_set_tfm(subreq, skcipher_geniv_cipher(geniv)); - ablkcipher_request_set_callback(subreq, req->creq.base.flags, - req->creq.base.complete, - req->creq.base.data); - ablkcipher_request_set_crypt(subreq, req->creq.src, req->creq.dst, - req->creq.nbytes, req->creq.info); - - if (test_and_set_bit(CHAINIV_STATE_INUSE, &ctx->state)) - goto postpone; - - if (ctx->queue.qlen) { - clear_bit(CHAINIV_STATE_INUSE, &ctx->state); - goto postpone; - } - - return async_chainiv_givencrypt_tail(req); - -postpone: - return async_chainiv_postpone_request(req); -} - -static void async_chainiv_do_postponed(struct work_struct *work) -{ - struct async_chainiv_ctx *ctx = container_of(work, - struct async_chainiv_ctx, - postponed); - struct skcipher_givcrypt_request *req; - struct ablkcipher_request *subreq; - int err; - - /* Only handle one request at a time to avoid hogging keventd. */ - spin_lock_bh(&ctx->lock); - req = skcipher_dequeue_givcrypt(&ctx->queue); - spin_unlock_bh(&ctx->lock); - - if (!req) { - async_chainiv_schedule_work(ctx); - return; - } - - subreq = skcipher_givcrypt_reqctx(req); - subreq->base.flags |= CRYPTO_TFM_REQ_MAY_SLEEP; - - err = async_chainiv_givencrypt_tail(req); - - local_bh_disable(); - skcipher_givcrypt_complete(req, err); - local_bh_enable(); -} - -static int async_chainiv_init(struct crypto_tfm *tfm) -{ - struct crypto_ablkcipher *geniv = __crypto_ablkcipher_cast(tfm); - struct async_chainiv_ctx *ctx = crypto_tfm_ctx(tfm); - char *iv; - - spin_lock_init(&ctx->lock); - - crypto_init_queue(&ctx->queue, 100); - INIT_WORK(&ctx->postponed, async_chainiv_do_postponed); - - iv = NULL; - if (!crypto_get_default_rng()) { - crypto_ablkcipher_crt(geniv)->givencrypt = - async_chainiv_givencrypt; - iv = ctx->iv; - } - - return chainiv_init_common(tfm, iv); -} - -static void async_chainiv_exit(struct crypto_tfm *tfm) -{ - struct async_chainiv_ctx *ctx = crypto_tfm_ctx(tfm); - - BUG_ON(test_bit(CHAINIV_STATE_INUSE, &ctx->state) || ctx->queue.qlen); - - skcipher_geniv_exit(tfm); -} - -static struct crypto_template chainiv_tmpl; - -static struct crypto_instance *chainiv_alloc(struct rtattr **tb) -{ - struct crypto_attr_type *algt; - struct crypto_instance *inst; - - algt = crypto_get_attr_type(tb); - if (IS_ERR(algt)) - return ERR_CAST(algt); - - inst = skcipher_geniv_alloc(&chainiv_tmpl, tb, 0, 0); - if (IS_ERR(inst)) - goto out; - - inst->alg.cra_init = chainiv_init; - inst->alg.cra_exit = skcipher_geniv_exit; - - inst->alg.cra_ctxsize = sizeof(struct chainiv_ctx); - - if (!crypto_requires_sync(algt->type, algt->mask)) { - inst->alg.cra_flags |= CRYPTO_ALG_ASYNC; - - inst->alg.cra_init = async_chainiv_init; - inst->alg.cra_exit = async_chainiv_exit; - - inst->alg.cra_ctxsize = sizeof(struct async_chainiv_ctx); - } - - inst->alg.cra_ctxsize += inst->alg.cra_ablkcipher.ivsize; - -out: - return inst; -} - -static struct crypto_template chainiv_tmpl = { - .name = "chainiv", - .alloc = chainiv_alloc, - .free = skcipher_geniv_free, - .module = THIS_MODULE, -}; - -static int __init chainiv_module_init(void) -{ - return crypto_register_template(&chainiv_tmpl); -} - -static void chainiv_module_exit(void) -{ - crypto_unregister_template(&chainiv_tmpl); -} - -module_init(chainiv_module_init); -module_exit(chainiv_module_exit); - -MODULE_LICENSE("GPL"); -MODULE_DESCRIPTION("Chain IV Generator"); -MODULE_ALIAS_CRYPTO("chainiv"); |