+static int skcipher_all_sg_nents(struct skcipher_ctx *ctx)
+{
+ struct skcipher_sg_list *sgl;
+ struct scatterlist *sg;
+ int nents = 0;
+
+ list_for_each_entry(sgl, &ctx->tsgl, list) {
+ sg = sgl->sg;
+
+ while (!sg->length)
+ sg++;
+
+ nents += sg_nents(sg);
+ }
+ return nents;
+}
+
+static int skcipher_recvmsg_async(struct socket *sock, struct msghdr *msg,
+ int flags)
+{
+ struct sock *sk = sock->sk;
+ struct alg_sock *ask = alg_sk(sk);
+ struct skcipher_ctx *ctx = ask->private;
+ struct skcipher_sg_list *sgl;
+ struct scatterlist *sg;
+ struct skcipher_async_req *sreq;
+ struct ablkcipher_request *req;
+ struct skcipher_async_rsgl *last_rsgl = NULL;
+ unsigned int txbufs = 0, len = 0, tx_nents = skcipher_all_sg_nents(ctx);
+ unsigned int reqlen = sizeof(struct skcipher_async_req) +
+ GET_REQ_SIZE(ctx) + GET_IV_SIZE(ctx);
+ int err = -ENOMEM;
+ bool mark = false;
+
+ lock_sock(sk);
+ req = kmalloc(reqlen, GFP_KERNEL);
+ if (unlikely(!req))
+ goto unlock;
+
+ sreq = GET_SREQ(req, ctx);
+ sreq->iocb = msg->msg_iocb;
+ memset(&sreq->first_sgl, '\0', sizeof(struct skcipher_async_rsgl));
+ INIT_LIST_HEAD(&sreq->list);
+ sreq->tsg = kcalloc(tx_nents, sizeof(*sg), GFP_KERNEL);
+ if (unlikely(!sreq->tsg)) {
+ kfree(req);
+ goto unlock;
+ }
+ sg_init_table(sreq->tsg, tx_nents);
+ memcpy(sreq->iv, ctx->iv, GET_IV_SIZE(ctx));
+ ablkcipher_request_set_tfm(req, crypto_ablkcipher_reqtfm(&ctx->req));
+ ablkcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
+ skcipher_async_cb, sk);
+
+ while (iov_iter_count(&msg->msg_iter)) {
+ struct skcipher_async_rsgl *rsgl;
+ int used;
+
+ if (!ctx->used) {
+ err = skcipher_wait_for_data(sk, flags);
+ if (err)
+ goto free;
+ }
+ sgl = list_first_entry(&ctx->tsgl,
+ struct skcipher_sg_list, list);
+ sg = sgl->sg;
+
+ while (!sg->length)
+ sg++;
+
+ used = min_t(unsigned long, ctx->used,
+ iov_iter_count(&msg->msg_iter));
+ used = min_t(unsigned long, used, sg->length);
+
+ if (txbufs == tx_nents) {
+ struct scatterlist *tmp;
+ int x;
+ /* Ran out of tx slots in async request
+ * need to expand */
+ tmp = kcalloc(tx_nents * 2, sizeof(*tmp),
+ GFP_KERNEL);
+ if (!tmp)
+ goto free;
+
+ sg_init_table(tmp, tx_nents * 2);
+ for (x = 0; x < tx_nents; x++)
+ sg_set_page(&tmp[x], sg_page(&sreq->tsg[x]),
+ sreq->tsg[x].length,
+ sreq->tsg[x].offset);
+ kfree(sreq->tsg);
+ sreq->tsg = tmp;
+ tx_nents *= 2;
+ mark = true;
+ }
+ /* Need to take over the tx sgl from ctx
+ * to the asynch req - these sgls will be freed later */
+ sg_set_page(sreq->tsg + txbufs++, sg_page(sg), sg->length,
+ sg->offset);
+
+ if (list_empty(&sreq->list)) {
+ rsgl = &sreq->first_sgl;
+ list_add_tail(&rsgl->list, &sreq->list);
+ } else {
+ rsgl = kmalloc(sizeof(*rsgl), GFP_KERNEL);
+ if (!rsgl) {
+ err = -ENOMEM;
+ goto free;
+ }
+ list_add_tail(&rsgl->list, &sreq->list);
+ }
+
+ used = af_alg_make_sg(&rsgl->sgl, &msg->msg_iter, used);
+ err = used;
+ if (used < 0)
+ goto free;
+ if (last_rsgl)
+ af_alg_link_sg(&last_rsgl->sgl, &rsgl->sgl);
+
+ last_rsgl = rsgl;
+ len += used;
+ skcipher_pull_sgl(sk, used, 0);
+ iov_iter_advance(&msg->msg_iter, used);
+ }
+
+ if (mark)
+ sg_mark_end(sreq->tsg + txbufs - 1);
+
+ ablkcipher_request_set_crypt(req, sreq->tsg, sreq->first_sgl.sgl.sg,
+ len, sreq->iv);
+ err = ctx->enc ? crypto_ablkcipher_encrypt(req) :
+ crypto_ablkcipher_decrypt(req);
+ if (err == -EINPROGRESS) {
+ atomic_inc(&ctx->inflight);
+ err = -EIOCBQUEUED;
+ goto unlock;
+ }
+free:
+ skcipher_free_async_sgls(sreq);
+ kfree(req);
+unlock:
+ skcipher_wmem_wakeup(sk);
+ release_sock(sk);
+ return err;
+}
+
+static int skcipher_recvmsg_sync(struct socket *sock, struct msghdr *msg,
+ int flags)