/*
 * Asynchronous Compression operations
 *
 * Copyright (c) 2016, Intel Corporation
 * Authors: Weigang Li <weigang.li@intel.com>
 *          Giovanni Cabiddu <giovanni.cabiddu@intel.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 *
 */
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/crypto.h>
#include <crypto/algapi.h>
#include <linux/cryptouser.h>
#include <net/netlink.h>
#include <crypto/internal/acompress.h>
#include <crypto/internal/scompress.h>
#include "internal.h"

static const struct crypto_type crypto_acomp_type;

#ifdef CONFIG_NET
static int crypto_acomp_report(struct sk_buff *skb, struct crypto_alg *alg)
{
	struct crypto_report_acomp racomp;

	strncpy(racomp.type, "acomp", sizeof(racomp.type));

	if (nla_put(skb, CRYPTOCFGA_REPORT_ACOMP,
		    sizeof(struct crypto_report_acomp), &racomp))
		goto nla_put_failure;
	return 0;

nla_put_failure:
	return -EMSGSIZE;
}
#else
static int crypto_acomp_report(struct sk_buff *skb, struct crypto_alg *alg)
{
	return -ENOSYS;
}
#endif

static void crypto_acomp_show(struct seq_file *m, struct crypto_alg *alg)
	__attribute__ ((unused));

static void crypto_acomp_show(struct seq_file *m, struct crypto_alg *alg)
{
	seq_puts(m, "type         : acomp\n");
}

static void crypto_acomp_exit_tfm(struct crypto_tfm *tfm)
{
	struct crypto_acomp *acomp = __crypto_acomp_tfm(tfm);
	struct acomp_alg *alg = crypto_acomp_alg(acomp);

	alg->exit(acomp);
}

static int crypto_acomp_init_tfm(struct crypto_tfm *tfm)
{
	struct crypto_acomp *acomp = __crypto_acomp_tfm(tfm);
	struct acomp_alg *alg = crypto_acomp_alg(acomp);

	if (tfm->__crt_alg->cra_type != &crypto_acomp_type)
		return crypto_init_scomp_ops_async(tfm);

	acomp->compress = alg->compress;
	acomp->decompress = alg->decompress;
	acomp->dst_free = alg->dst_free;
	acomp->reqsize = alg->reqsize;

	if (alg->exit)
		acomp->base.exit = crypto_acomp_exit_tfm;

	if (alg->init)
		return alg->init(acomp);

	return 0;
}

static unsigned int crypto_acomp_extsize(struct crypto_alg *alg)
{
	int extsize = crypto_alg_extsize(alg);

	if (alg->cra_type != &crypto_acomp_type)
		extsize += sizeof(struct crypto_scomp *);

	return extsize;
}

static const struct crypto_type crypto_acomp_type = {
	.extsize = crypto_acomp_extsize,
	.init_tfm = crypto_acomp_init_tfm,
#ifdef CONFIG_PROC_FS
	.show = crypto_acomp_show,
#endif
	.report = crypto_acomp_report,
	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
	.maskset = CRYPTO_ALG_TYPE_ACOMPRESS_MASK,
	.type = CRYPTO_ALG_TYPE_ACOMPRESS,
	.tfmsize = offsetof(struct crypto_acomp, base),
};

struct crypto_acomp *crypto_alloc_acomp(const char *alg_name, u32 type,
					u32 mask)
{
	return crypto_alloc_tfm(alg_name, &crypto_acomp_type, type, mask);
}
EXPORT_SYMBOL_GPL(crypto_alloc_acomp);

struct acomp_req *acomp_request_alloc(struct crypto_acomp *acomp)
{
	struct crypto_tfm *tfm = crypto_acomp_tfm(acomp);
	struct acomp_req *req;

	req = __acomp_request_alloc(acomp);
	if (req && (tfm->__crt_alg->cra_type != &crypto_acomp_type))
		return crypto_acomp_scomp_alloc_ctx(req);

	return req;
}
EXPORT_SYMBOL_GPL(acomp_request_alloc);

void acomp_request_free(struct acomp_req *req)
{
	struct crypto_acomp *acomp = crypto_acomp_reqtfm(req);
	struct crypto_tfm *tfm = crypto_acomp_tfm(acomp);

	if (tfm->__crt_alg->cra_type != &crypto_acomp_type)
		crypto_acomp_scomp_free_ctx(req);

	if (req->flags & CRYPTO_ACOMP_ALLOC_OUTPUT) {
		acomp->dst_free(req->dst);
		req->dst = NULL;
	}

	__acomp_request_free(req);
}
EXPORT_SYMBOL_GPL(acomp_request_free);

int crypto_register_acomp(struct acomp_alg *alg)
{
	struct crypto_alg *base = &alg->base;

	base->cra_type = &crypto_acomp_type;
	base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
	base->cra_flags |= CRYPTO_ALG_TYPE_ACOMPRESS;

	return crypto_register_alg(base);
}
EXPORT_SYMBOL_GPL(crypto_register_acomp);

int crypto_unregister_acomp(struct acomp_alg *alg)
{
	return crypto_unregister_alg(&alg->base);
}
EXPORT_SYMBOL_GPL(crypto_unregister_acomp);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Asynchronous compression type");