path: root/drivers/crypto/caam/caampkc.c

// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
/*
 * caam - Freescale FSL CAAM support for Public Key Cryptography
 *
 * Copyright 2016 Freescale Semiconductor, Inc.
 * Copyright 2018-2019, 2023 NXP
 *
 * There is no Shared Descriptor for PKC so that the Job Descriptor must carry
 * all the desired key parameters, input and output pointers.
 */
#include "compat.h"
#include "regs.h"
#include "intern.h"
#include "jr.h"
#include "error.h"
#include "desc_constr.h"
#include "sg_sw_sec4.h"
#include "caampkc.h"
#include <crypto/internal/engine.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/string.h>

#define DESC_RSA_PUB_LEN	(2 * CAAM_CMD_SZ + SIZEOF_RSA_PUB_PDB)
#define DESC_RSA_PRIV_F1_LEN	(2 * CAAM_CMD_SZ + \
				 SIZEOF_RSA_PRIV_F1_PDB)
#define DESC_RSA_PRIV_F2_LEN	(2 * CAAM_CMD_SZ + \
				 SIZEOF_RSA_PRIV_F2_PDB)
#define DESC_RSA_PRIV_F3_LEN	(2 * CAAM_CMD_SZ + \
				 SIZEOF_RSA_PRIV_F3_PDB)
#define CAAM_RSA_MAX_INPUT_SIZE	512 /* for a 4096-bit modulus */

/* buffer filled with zeros, used for padding */
static u8 *zero_buffer;

/*
 * variable used to avoid double free of resources in case
 * algorithm registration was unsuccessful
 */
static bool init_done;

struct caam_akcipher_alg {
	struct akcipher_engine_alg akcipher;
	bool registered;
};

static void rsa_io_unmap(struct device *dev, struct rsa_edesc *edesc,
			 struct akcipher_request *req)
{
	struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);

	dma_unmap_sg(dev, req->dst, edesc->dst_nents, DMA_FROM_DEVICE);
	dma_unmap_sg(dev, req_ctx->fixup_src, edesc->src_nents, DMA_TO_DEVICE);

	if (edesc->sec4_sg_bytes)
		dma_unmap_single(dev, edesc->sec4_sg_dma, edesc->sec4_sg_bytes,
				 DMA_TO_DEVICE);
}

static void rsa_pub_unmap(struct device *dev, struct rsa_edesc *edesc,
			  struct akcipher_request *req)
{
	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
	struct caam_rsa_key *key = &ctx->key;
	struct rsa_pub_pdb *pdb = &edesc->pdb.pub;

	dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
	dma_unmap_single(dev, pdb->e_dma, key->e_sz, DMA_TO_DEVICE);
}

static void rsa_priv_f1_unmap(struct device *dev, struct rsa_edesc *edesc,
			      struct akcipher_request *req)
{
	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
	struct caam_rsa_key *key = &ctx->key;
	struct rsa_priv_f1_pdb *pdb = &edesc->pdb.priv_f1;

	dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
	dma_unmap_single(dev, pdb->d_dma, key->d_sz, DMA_TO_DEVICE);
}

static void rsa_priv_f2_unmap(struct device *dev, struct rsa_edesc *edesc,
			      struct akcipher_request *req)
{
	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
	struct caam_rsa_key *key = &ctx->key;
	struct rsa_priv_f2_pdb *pdb = &edesc->pdb.priv_f2;
	size_t p_sz = key->p_sz;
	size_t q_sz = key->q_sz;

	dma_unmap_single(dev, pdb->d_dma, key->d_sz, DMA_TO_DEVICE);
	dma_unmap_single(dev, pdb->p_dma, p_sz, DMA_TO_DEVICE);
	dma_unmap_single(dev, pdb->q_dma, q_sz, DMA_TO_DEVICE);
	dma_unmap_single(dev, pdb->tmp1_dma, p_sz,