// SPDX-License-Identifier: GPL-2.0-only
/*
 * AES ECB routines supporting the Power 7+ Nest Accelerators driver
 *
 * Copyright (C) 2011-2012 International Business Machines Inc.
 *
 * Author: Kent Yoder <yoder1@us.ibm.com>
 */

#include <crypto/aes.h>
#include <crypto/internal/skcipher.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <asm/vio.h>

#include "nx_csbcpb.h"
#include "nx.h"


static int ecb_aes_nx_set_key(struct crypto_skcipher *tfm,
                              const u8               *in_key,
                              unsigned int            key_len)
{
        struct nx_crypto_ctx *nx_ctx = crypto_skcipher_ctx(tfm);
        struct nx_csbcpb *csbcpb = (struct nx_csbcpb *)nx_ctx->csbcpb;

        nx_ctx_init(nx_ctx, HCOP_FC_AES);

        switch (key_len) {
        case AES_KEYSIZE_128:
                NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_128);
                nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_128];
                break;
        case AES_KEYSIZE_192:
                NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_192);
                nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_192];
                break;
        case AES_KEYSIZE_256:
                NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_256);
                nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_256];
                break;
        default:
                return -EINVAL;
        }

        csbcpb->cpb.hdr.mode = NX_MODE_AES_ECB;
        memcpy(csbcpb->cpb.aes_ecb.key, in_key, key_len);

        return 0;
}

static int ecb_aes_nx_crypt(struct skcipher_request *req,
                            int                      enc)
{
        struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
        struct nx_crypto_ctx *nx_ctx = crypto_skcipher_ctx(tfm);
        struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
        unsigned long irq_flags;
        unsigned int processed = 0, to_process;
        int rc;

        spin_lock_irqsave(&nx_ctx->lock, irq_flags);

        if (enc)
                NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT;
        else
                NX_CPB_FDM(csbcpb) &= ~NX_FDM_ENDE_ENCRYPT;

        do {
                to_process = req->cryptlen - processed;

                rc = nx_build_sg_lists(nx_ctx, NULL, req->dst, req->src,
                                       &to_process, processed, NULL);
                if (rc)
                        goto out;

                if (!nx_ctx->op.inlen || !nx_ctx->op.outlen) {
                        rc = -EINVAL;
                        goto out;
                }

                rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
                                   req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
                if (rc)
                        goto out;

                atomic_inc(&(nx_ctx->stats->aes_ops));
                atomic64_add(be32_to_cpu(csbcpb->csb.processed_byte_count),
                             &(nx_ctx->stats->aes_bytes));

                processed += to_process;
        } while (processed < req->cryptlen);

out:
        spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
        return rc;
}

static int ecb_aes_nx_encrypt(struct skcipher_request *req)
{
        return ecb_aes_nx_crypt(req, 1);
}

static int ecb_aes_nx_decrypt(struct skcipher_request *req)
{
        return ecb_aes_nx_crypt(req, 0);
}

struct skcipher_alg nx_ecb_aes_alg = {
        .base.cra_name          = "ecb(aes)",
        .base.cra_driver_name   = "ecb-aes-nx",
        .base.cra_priority      = 300,
        .base.cra_blocksize     = AES_BLOCK_SIZE,
        .base.cra_alignmask     = 0xf,
        .base.cra_ctxsize       = sizeof(struct nx_crypto_ctx),
        .base.cra_module        = THIS_MODULE,
        .init                   = nx_crypto_ctx_aes_ecb_init,
        .exit                   = nx_crypto_ctx_skcipher_exit,
        .min_keysize            = AES_MIN_KEY_SIZE,
        .max_keysize            = AES_MAX_KEY_SIZE,
        .setkey                 = ecb_aes_nx_set_key,
        .encrypt                = ecb_aes_nx_encrypt,
        .decrypt                = ecb_aes_nx_decrypt,
};