Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0
/*
 * amlogic-cipher.c - hardware cryptographic offloader for Amlogic GXL SoC
 *
 * Copyright (C) 2018-2019 Corentin LABBE <clabbe@baylibre.com>
 *
 * This file add support for AES cipher with 128,192,256 bits keysize in
 * CBC and ECB mode.
 */
 
#include <linux/crypto.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <crypto/scatterwalk.h>
#include <linux/scatterlist.h>
#include <linux/dma-mapping.h>
#include <crypto/internal/skcipher.h>
#include "amlogic-gxl.h"
 
static int get_engine_number(struct meson_dev *mc)
{
<------>return atomic_inc_return(&mc->flow) % MAXFLOW;
}
 
static bool meson_cipher_need_fallback(struct skcipher_request *areq)
{
<------>struct scatterlist *src_sg = areq->src;
<------>struct scatterlist *dst_sg = areq->dst;
 
<------>if (areq->cryptlen == 0)
<------><------>return true;
 
<------>if (sg_nents(src_sg) != sg_nents(dst_sg))
<------><------>return true;
 
<------>/* KEY/IV descriptors use 3 desc */
<------>if (sg_nents(src_sg) > MAXDESC - 3 || sg_nents(dst_sg) > MAXDESC - 3)
<------><------>return true;
 
<------>while (src_sg && dst_sg) {
<------><------>if ((src_sg->length % 16) != 0)
<------><------><------>return true;
<------><------>if ((dst_sg->length % 16) != 0)
<------><------><------>return true;
<------><------>if (src_sg->length != dst_sg->length)
<------><------><------>return true;
<------><------>if (!IS_ALIGNED(src_sg->offset, sizeof(u32)))
<------><------><------>return true;
<------><------>if (!IS_ALIGNED(dst_sg->offset, sizeof(u32)))
<------><------><------>return true;
<------><------>src_sg = sg_next(src_sg);
<------><------>dst_sg = sg_next(dst_sg);
<------>}
 
<------>return false;
}
 
static int meson_cipher_do_fallback(struct skcipher_request *areq)
{
<------>struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
<------>struct meson_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
<------>struct meson_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
<------>int err;
#ifdef CONFIG_CRYPTO_DEV_AMLOGIC_GXL_DEBUG
<------>struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
<------>struct meson_alg_template *algt;
 
<------>algt = container_of(alg, struct meson_alg_template, alg.skcipher);
<------>algt->stat_fb++;
#endif
<------>skcipher_request_set_tfm(&rctx->fallback_req, op->fallback_tfm);
<------>skcipher_request_set_callback(&rctx->fallback_req, areq->base.flags,
<------><------><------><------>      areq->base.complete, areq->base.data);
<------>skcipher_request_set_crypt(&rctx->fallback_req, areq->src, areq->dst,
<------><------><------><------>   areq->cryptlen, areq->iv);
 
<------>if (rctx->op_dir == MESON_DECRYPT)
<------><------>err = crypto_skcipher_decrypt(&rctx->fallback_req);
<------>else
<------><------>err = crypto_skcipher_encrypt(&rctx->fallback_req);
<------>return err;
}
 
static int meson_cipher(struct skcipher_request *areq)
{
<------>struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
<------>struct meson_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
<------>struct meson_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
<------>struct meson_dev *mc = op->mc;
<------>struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
<------>struct meson_alg_template *algt;
<------>int flow = rctx->flow;
<------>unsigned int todo, eat, len;
<------>struct scatterlist *src_sg = areq->src;
<------>struct scatterlist *dst_sg = areq->dst;
<------>struct meson_desc *desc;
<------>int nr_sgs, nr_sgd;
<------>int i, err = 0;
<------>unsigned int keyivlen, ivsize, offset, tloffset;
<------>dma_addr_t phykeyiv;
<------>void *backup_iv = NULL, *bkeyiv;
<------>u32 v;
 
<------>algt = container_of(alg, struct meson_alg_template, alg.skcipher);
 
<------>dev_dbg(mc->dev, "%s %s %u %x IV(%u) key=%u flow=%d\n", __func__,
<------><------>crypto_tfm_alg_name(areq->base.tfm),
<------><------>areq->cryptlen,
<------><------>rctx->op_dir, crypto_skcipher_ivsize(tfm),
<------><------>op->keylen, flow);
 
#ifdef CONFIG_CRYPTO_DEV_AMLOGIC_GXL_DEBUG
<------>algt->stat_req++;
<------>mc->chanlist[flow].stat_req++;
#endif
 
<------>/*
<------> * The hardware expect a list of meson_desc structures.
<------> * The 2 first structures store key
<------> * The third stores IV
<------> */
<------>bkeyiv = kzalloc(48, GFP_KERNEL | GFP_DMA);
<------>if (!bkeyiv)
<------><------>return -ENOMEM;
 
<------>memcpy(bkeyiv, op->key, op->keylen);
<------>keyivlen = op->keylen;
 
<------>ivsize = crypto_skcipher_ivsize(tfm);
<------>if (areq->iv && ivsize > 0) {
<------><------>if (ivsize > areq->cryptlen) {
<------><------><------>dev_err(mc->dev, "invalid ivsize=%d vs len=%d\n", ivsize, areq->cryptlen);
<------><------><------>err = -EINVAL;
<------><------><------>goto theend;
<------><------>}
<------><------>memcpy(bkeyiv + 32, areq->iv, ivsize);
<------><------>keyivlen = 48;
<------><------>if (rctx->op_dir == MESON_DECRYPT) {
<------><------><------>backup_iv = kzalloc(ivsize, GFP_KERNEL);
<------><------><------>if (!backup_iv) {
<------><------><------><------>err = -ENOMEM;
<------><------><------><------>goto theend;
<------><------><------>}
<------><------><------>offset = areq->cryptlen - ivsize;
<------><------><------>scatterwalk_map_and_copy(backup_iv, areq->src, offset,
<------><------><------><------><------><------> ivsize, 0);
<------><------>}
<------>}
<------>if (keyivlen == 24)
<------><------>keyivlen = 32;
 
<------>phykeyiv = dma_map_single(mc->dev, bkeyiv, keyivlen,
<------><------><------><------>  DMA_TO_DEVICE);
<------>err = dma_mapping_error(mc->dev, phykeyiv);
<------>if (err) {
<------><------>dev_err(mc->dev, "Cannot DMA MAP KEY IV\n");
<------><------>goto theend;
<------>}
 
<------>tloffset = 0;
<------>eat = 0;
<------>i = 0;
<------>while (keyivlen > eat) {
<------><------>desc = &mc->chanlist[flow].tl[tloffset];
<------><------>memset(desc, 0, sizeof(struct meson_desc));
<------><------>todo = min(keyivlen - eat, 16u);
<------><------>desc->t_src = cpu_to_le32(phykeyiv + i * 16);
<------><------>desc->t_dst = cpu_to_le32(i * 16);
<------><------>v = (MODE_KEY << 20) | DESC_OWN | 16;
<------><------>desc->t_status = cpu_to_le32(v);
 
<------><------>eat += todo;
<------><------>i++;
<------><------>tloffset++;
<------>}
 
<------>if (areq->src == areq->dst) {
<------><------>nr_sgs = dma_map_sg(mc->dev, areq->src, sg_nents(areq->src),
<------><------><------><------>    DMA_BIDIRECTIONAL);
<------><------>if (nr_sgs < 0) {
<------><------><------>dev_err(mc->dev, "Invalid SG count %d\n", nr_sgs);
<------><------><------>err = -EINVAL;
<------><------><------>goto theend;
<------><------>}
<------><------>nr_sgd = nr_sgs;
<------>} else {
<------><------>nr_sgs = dma_map_sg(mc->dev, areq->src, sg_nents(areq->src),
<------><------><------><------>    DMA_TO_DEVICE);
<------><------>if (nr_sgs < 0 || nr_sgs > MAXDESC - 3) {
<------><------><------>dev_err(mc->dev, "Invalid SG count %d\n", nr_sgs);
<------><------><------>err = -EINVAL;
<------><------><------>goto theend;
<------><------>}
<------><------>nr_sgd = dma_map_sg(mc->dev, areq->dst, sg_nents(areq->dst),
<------><------><------><------>    DMA_FROM_DEVICE);
<------><------>if (nr_sgd < 0 || nr_sgd > MAXDESC - 3) {
<------><------><------>dev_err(mc->dev, "Invalid SG count %d\n", nr_sgd);
<------><------><------>err = -EINVAL;
<------><------><------>goto theend;
<------><------>}
<------>}
 
<------>src_sg = areq->src;
<------>dst_sg = areq->dst;
<------>len = areq->cryptlen;
<------>while (src_sg) {
<------><------>desc = &mc->chanlist[flow].tl[tloffset];
<------><------>memset(desc, 0, sizeof(struct meson_desc));
 
<------><------>desc->t_src = cpu_to_le32(sg_dma_address(src_sg));
<------><------>desc->t_dst = cpu_to_le32(sg_dma_address(dst_sg));
<------><------>todo = min(len, sg_dma_len(src_sg));
<------><------>v = (op->keymode << 20) | DESC_OWN | todo | (algt->blockmode << 26);
<------><------>if (rctx->op_dir)
<------><------><------>v |= DESC_ENCRYPTION;
<------><------>len -= todo;
 
<------><------>if (!sg_next(src_sg))
<------><------><------>v |= DESC_LAST;
<------><------>desc->t_status = cpu_to_le32(v);
<------><------>tloffset++;
<------><------>src_sg = sg_next(src_sg);
<------><------>dst_sg = sg_next(dst_sg);
<------>}
 
<------>reinit_completion(&mc->chanlist[flow].complete);
<------>mc->chanlist[flow].status = 0;
<------>writel(mc->chanlist[flow].t_phy | 2, mc->base + (flow << 2));
<------>wait_for_completion_interruptible_timeout(&mc->chanlist[flow].complete,
<------><------><------><------><------><------>  msecs_to_jiffies(500));
<------>if (mc->chanlist[flow].status == 0) {
<------><------>dev_err(mc->dev, "DMA timeout for flow %d\n", flow);
<------><------>err = -EINVAL;
<------>}
 
<------>dma_unmap_single(mc->dev, phykeyiv, keyivlen, DMA_TO_DEVICE);
 
<------>if (areq->src == areq->dst) {
<------><------>dma_unmap_sg(mc->dev, areq->src, nr_sgs, DMA_BIDIRECTIONAL);
<------>} else {
<------><------>dma_unmap_sg(mc->dev, areq->src, nr_sgs, DMA_TO_DEVICE);
<------><------>dma_unmap_sg(mc->dev, areq->dst, nr_sgd, DMA_FROM_DEVICE);
<------>}
 
<------>if (areq->iv && ivsize > 0) {
<------><------>if (rctx->op_dir == MESON_DECRYPT) {
<------><------><------>memcpy(areq->iv, backup_iv, ivsize);
<------><------>} else {
<------><------><------>scatterwalk_map_and_copy(areq->iv, areq->dst,
<------><------><------><------><------><------> areq->cryptlen - ivsize,
<------><------><------><------><------><------> ivsize, 0);
<------><------>}
<------>}
theend:
<------>kfree_sensitive(bkeyiv);
<------>kfree_sensitive(backup_iv);
 
<------>return err;
}
 
static int meson_handle_cipher_request(struct crypto_engine *engine,
<------><------><------><------>       void *areq)
{
<------>int err;
<------>struct skcipher_request *breq = container_of(areq, struct skcipher_request, base);
 
<------>err = meson_cipher(breq);
<------>local_bh_disable();
<------>crypto_finalize_skcipher_request(engine, breq, err);
<------>local_bh_enable();
 
<------>return 0;
}
 
int meson_skdecrypt(struct skcipher_request *areq)
{
<------>struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
<------>struct meson_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
<------>struct meson_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
<------>struct crypto_engine *engine;
<------>int e;
 
<------>rctx->op_dir = MESON_DECRYPT;
<------>if (meson_cipher_need_fallback(areq))
<------><------>return meson_cipher_do_fallback(areq);
<------>e = get_engine_number(op->mc);
<------>engine = op->mc->chanlist[e].engine;
<------>rctx->flow = e;
 
<------>return crypto_transfer_skcipher_request_to_engine(engine, areq);
}
 
int meson_skencrypt(struct skcipher_request *areq)
{
<------>struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
<------>struct meson_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
<------>struct meson_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
<------>struct crypto_engine *engine;
<------>int e;
 
<------>rctx->op_dir = MESON_ENCRYPT;
<------>if (meson_cipher_need_fallback(areq))
<------><------>return meson_cipher_do_fallback(areq);
<------>e = get_engine_number(op->mc);
<------>engine = op->mc->chanlist[e].engine;
<------>rctx->flow = e;
 
<------>return crypto_transfer_skcipher_request_to_engine(engine, areq);
}
 
int meson_cipher_init(struct crypto_tfm *tfm)
{
<------>struct meson_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm);
<------>struct meson_alg_template *algt;
<------>const char *name = crypto_tfm_alg_name(tfm);
<------>struct crypto_skcipher *sktfm = __crypto_skcipher_cast(tfm);
<------>struct skcipher_alg *alg = crypto_skcipher_alg(sktfm);
 
<------>memset(op, 0, sizeof(struct meson_cipher_tfm_ctx));
 
<------>algt = container_of(alg, struct meson_alg_template, alg.skcipher);
<------>op->mc = algt->mc;
 
<------>op->fallback_tfm = crypto_alloc_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK);
<------>if (IS_ERR(op->fallback_tfm)) {
<------><------>dev_err(op->mc->dev, "ERROR: Cannot allocate fallback for %s %ld\n",
<------><------><------>name, PTR_ERR(op->fallback_tfm));
<------><------>return PTR_ERR(op->fallback_tfm);
<------>}
 
<------>sktfm->reqsize = sizeof(struct meson_cipher_req_ctx) +
<------><------><------> crypto_skcipher_reqsize(op->fallback_tfm);
 
<------>op->enginectx.op.do_one_request = meson_handle_cipher_request;
<------>op->enginectx.op.prepare_request = NULL;
<------>op->enginectx.op.unprepare_request = NULL;
 
<------>return 0;
}
 
void meson_cipher_exit(struct crypto_tfm *tfm)
{
<------>struct meson_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm);
 
<------>kfree_sensitive(op->key);
<------>crypto_free_skcipher(op->fallback_tfm);
}
 
int meson_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
<------><------>     unsigned int keylen)
{
<------>struct meson_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
<------>struct meson_dev *mc = op->mc;
 
<------>switch (keylen) {
<------>case 128 / 8:
<------><------>op->keymode = MODE_AES_128;
<------><------>break;
<------>case 192 / 8:
<------><------>op->keymode = MODE_AES_192;
<------><------>break;
<------>case 256 / 8:
<------><------>op->keymode = MODE_AES_256;
<------><------>break;
<------>default:
<------><------>dev_dbg(mc->dev, "ERROR: Invalid keylen %u\n", keylen);
<------><------>return -EINVAL;
<------>}
<------>kfree_sensitive(op->key);
<------>op->keylen = keylen;
<------>op->key = kmemdup(key, keylen, GFP_KERNEL | GFP_DMA);
<------>if (!op->key)
<------><------>return -ENOMEM;
 
<------>return crypto_skcipher_setkey(op->fallback_tfm, key, keylen);
}