path: root/drivers/crypto/qce/aead.c

// SPDX-License-Identifier: GPL-2.0-only

/*
 * Copyright (C) 2021, Linaro Limited. All rights reserved.
 */
#include <linux/dma-mapping.h>
#include <linux/interrupt.h>
#include <linux/string.h>
#include <crypto/gcm.h>
#include <crypto/authenc.h>
#include <crypto/internal/aead.h>
#include <crypto/internal/des.h>
#include <crypto/sha1.h>
#include <crypto/sha2.h>
#include <crypto/scatterwalk.h>
#include "aead.h"

#define CCM_NONCE_ADATA_SHIFT		6
#define CCM_NONCE_AUTHSIZE_SHIFT	3
#define MAX_CCM_ADATA_HEADER_LEN        6

static LIST_HEAD(aead_algs);

static void qce_aead_done(void *data)
{
	struct crypto_async_request *async_req = data;
	struct aead_request *req = aead_request_cast(async_req);
	struct qce_aead_reqctx *rctx = aead_request_ctx_dma(req);
	struct qce_aead_ctx *ctx = crypto_tfm_ctx(async_req->tfm);
	struct qce_alg_template *tmpl = to_aead_tmpl(crypto_aead_reqtfm(req));
	struct qce_device *qce = tmpl->qce;
	struct qce_result_dump *result_buf = qce->dma.result_buf;
	enum dma_data_direction dir_src, dir_dst;
	bool diff_dst;
	int error;
	u32 status;
	unsigned int totallen;
	unsigned char tag[SHA256_DIGEST_SIZE] = {0};

	diff_dst = (req->src != req->dst) ? true : false;
	dir_src = diff_dst ? DMA_TO_DEVICE : DMA_BIDIRECTIONAL;
	dir_dst = diff_dst ? DMA_FROM_DEVICE : DMA_BIDIRECTIONAL;

	error = qce_dma_terminate_all(&qce->dma);
	if (error)
		dev_dbg(qce->dev, "aead dma termination error (%d)\n",
			error);
	if (diff_dst)
		dma_unmap_sg(qce->dev, rctx->src_sg, rctx->src_nents, dir_src);

	dma_unmap_sg(qce->dev, rctx->dst_sg, rctx->dst_nents, dir_dst);

	if (IS_CCM(rctx->flags)) {
		if (req->assoclen) {
			sg_free_table(&rctx->src_tbl);
			if (diff_dst)
				sg_free_table(&rctx->dst_tbl);
		} else {
			if (!(IS_DECRYPT(rctx->flags) && !diff_dst))
				sg_free_table(&rctx->dst_tbl);
		}
	} else {
		sg_free_table(&rctx->dst_tbl);
	}

	error = qce_check_status(qce, &status);
	if (error < 0 && (error != -EBADMSG))
		dev_err(qce->dev, "aead operation error (%x)\n", status);

	if (IS_ENCRYPT(rctx->flags)) {
		totallen = req->cryptlen + req->assoclen;
		if (IS_CCM(rctx->flags))
			scatterwalk_map_and_copy(rctx->ccmresult_buf, req->dst,
						 totallen, ctx->authsize, 1);
		else
			scatterwalk_map_and_copy(result_buf->auth_iv, req->dst,
						 totallen, ctx->authsize, 1);

	} else if (!IS_CCM(rctx->flags)) {
		totallen = req->cryptlen + req->assoclen - ctx->authsize;
		scatterwalk_map_and_copy(tag, req->src, totallen, ctx->authsize, 0);
		if (memcmp(result_buf->auth_iv, tag, ctx->authsize)) {
			pr_err("Bad message error\n");
			error = -EBADMSG;
		}
	}

	qce->async_req_done(qce, error);
}

static struct scatterlist *
qce_aead_prepare_result_buf(struct sg_table *tbl, struct aead_request *req)
{
	struct qce_aead_reqctx *rctx = aead_request_ctx_dma(req);
	struct qce_alg_template *tmpl = to_aead_tmpl(crypto_aead_reqtfm(req));
	struct qce_device *qce = tmpl->qce;

	sg_init_one(&rctx->result_sg, qce->dma.result_buf, QCE_RESULT_BUF_SZ);
	return qce_sgtable_add(tbl, &rctx->result_sg, QCE_RESULT_BUF_SZ);
}

static struct scatterlist *
qce_aead_prepare_ccm_result_buf(struct sg_table *tbl, struct aead_request *req)
{
	struct qce_aead_reqctx *rctx = aead_request_ctx_dma(req);

	sg_init_one(&rctx->result_sg, rctx->ccmresult_buf, QCE_BAM_BURST_SIZE);
	return qce_sgtable_add(tbl, &rctx->result_sg, QCE_BAM_BURST_SIZE);
}

static struct scatterlist *
qce_aead_prepare_dst_buf(struct aead_request *req)
{
	struct qce_aead_reqctx *rctx = aead_request_ctx_dma(req);
	struct qce_alg_template *tmpl = to_aead_tmpl(crypto_aead_reqtfm(req));
	struct qce_device *qce = tmpl->qce;
	struct scatterlist *sg, *msg_sg, __sg[2];
	gfp_t gfp;
	unsigned int assoclen = req->assoclen;
	unsigned int totallen;
	int ret;

	totallen = rctx->cryptlen + assoclen;
	rctx->dst_nents = sg_nents_for_len(req->dst, totallen);
	if (rctx->dst_nents < 0) {
		dev_err(qce->dev, "Invalid numbers of dst SG.\n");
		return ERR_PTR(-EINVAL);