+static int cts_cbc_encrypt(struct skcipher_request *req)
+{
+ struct crypto_cts_reqctx *rctx = skcipher_request_ctx(req);
+ struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+ struct skcipher_request *subreq = &rctx->subreq;
+ int bsize = crypto_skcipher_blocksize(tfm);
+ u8 d[bsize * 2] __attribute__ ((aligned(__alignof__(u32))));
+ struct scatterlist *sg;
+ unsigned int offset;
+ int lastn;
+
+ offset = rctx->offset;
+ lastn = req->cryptlen - offset;
+
+ sg = scatterwalk_ffwd(rctx->sg, req->dst, offset - bsize);
+ scatterwalk_map_and_copy(d + bsize, sg, 0, bsize, 0);
+
+ memset(d, 0, bsize);
+ scatterwalk_map_and_copy(d, req->src, offset, lastn, 0);
+
+ scatterwalk_map_and_copy(d, sg, 0, bsize + lastn, 1);
+ memzero_explicit(d, sizeof(d));
+
+ skcipher_request_set_callback(subreq, req->base.flags &
+ CRYPTO_TFM_REQ_MAY_BACKLOG,
+ cts_cbc_crypt_done, req);
+ skcipher_request_set_crypt(subreq, sg, sg, bsize, req->iv);
+ return crypto_skcipher_encrypt(subreq);
+}