diff options
Diffstat (limited to 'crypto')
-rw-r--r-- | crypto/chainiv.c | 208 |
1 files changed, 200 insertions, 8 deletions
diff --git a/crypto/chainiv.c b/crypto/chainiv.c index 38868d160b47..d17fa0454dc3 100644 --- a/crypto/chainiv.c +++ b/crypto/chainiv.c @@ -16,16 +16,34 @@ #include <crypto/internal/skcipher.h> #include <linux/err.h> #include <linux/init.h> +#include <linux/kernel.h> #include <linux/module.h> #include <linux/random.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); @@ -80,26 +98,187 @@ unlock: return chainiv_givencrypt(req); } +static int chainiv_init_common(struct crypto_tfm *tfm) +{ + tfm->crt_ablkcipher.reqsize = sizeof(struct ablkcipher_request); + + return 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_ablkcipher_ctx(geniv); + struct chainiv_ctx *ctx = crypto_tfm_ctx(tfm); spin_lock_init(&ctx->lock); - tfm->crt_ablkcipher.reqsize = sizeof(struct ablkcipher_request); + return chainiv_init_common(tfm); +} - return skcipher_geniv_init(tfm); +static int async_chainiv_schedule_work(struct async_chainiv_ctx *ctx) +{ + int queued; + + if (!ctx->queue.qlen) { + smp_mb__before_clear_bit(); + clear_bit(CHAINIV_STATE_INUSE, &ctx->state); + + if (!ctx->queue.qlen || + test_and_set_bit(CHAINIV_STATE_INUSE, &ctx->state)) + goto out; + } + + queued = schedule_work(&ctx->postponed); + BUG_ON(!queued); + +out: + return ctx->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 int async_chainiv_givencrypt_first(struct skcipher_givcrypt_request *req) +{ + struct crypto_ablkcipher *geniv = skcipher_givcrypt_reqtfm(req); + struct async_chainiv_ctx *ctx = crypto_ablkcipher_ctx(geniv); + + if (test_and_set_bit(CHAINIV_STATE_INUSE, &ctx->state)) + goto out; + + if (crypto_ablkcipher_crt(geniv)->givencrypt != + async_chainiv_givencrypt_first) + goto unlock; + + crypto_ablkcipher_crt(geniv)->givencrypt = async_chainiv_givencrypt; + get_random_bytes(ctx->iv, crypto_ablkcipher_ivsize(geniv)); + +unlock: + clear_bit(CHAINIV_STATE_INUSE, &ctx->state); + +out: + return async_chainiv_givencrypt(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; + + /* 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; + + async_chainiv_givencrypt_tail(req); +} + +static int async_chainiv_init(struct crypto_tfm *tfm) +{ + struct async_chainiv_ctx *ctx = crypto_tfm_ctx(tfm); + + spin_lock_init(&ctx->lock); + + crypto_init_queue(&ctx->queue, 100); + INIT_WORK(&ctx->postponed, async_chainiv_do_postponed); + + return chainiv_init_common(tfm); +} + +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; + int err; - inst = skcipher_geniv_alloc(&chainiv_tmpl, tb, 0, - CRYPTO_ALG_ASYNC); + algt = crypto_get_attr_type(tb); + err = PTR_ERR(algt); + if (IS_ERR(algt)) + return ERR_PTR(err); + + inst = skcipher_geniv_alloc(&chainiv_tmpl, tb, 0, 0); if (IS_ERR(inst)) goto out; @@ -108,8 +287,21 @@ static struct crypto_instance *chainiv_alloc(struct rtattr **tb) inst->alg.cra_init = chainiv_init; inst->alg.cra_exit = skcipher_geniv_exit; - inst->alg.cra_ctxsize = sizeof(struct chainiv_ctx) + - inst->alg.cra_ablkcipher.ivsize; + 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_ablkcipher.givencrypt = + async_chainiv_givencrypt_first; + + 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; |