/* In-software asymmetric public-key crypto subtype
 *
 * See Documentation/crypto/asymmetric-keys.txt
 *
 * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public Licence
 * as published by the Free Software Foundation; either version
 * 2 of the Licence, or (at your option) any later version.
 */

//#define pr_fmt(fmt) "PKEY: "fmt
//#include <linux/module.h>
//#include <linux/export.h>
//#include <linux/kernel.h>
//#include <linux/slab.h>
//#include <linux/seq_file.h>
//#include <linux/scatterlist.h>
//#include <keys/asymmetric-subtype.h>
//#include <crypto/public_key.h>
//#include <crypto/akcipher.h>
//
// MODULE_LICENSE("GPL");

#include "public_key.h"

#include "../rewrite/Lib.SoulExtraction.rewrite.h"

/*
 * Provide a part of a description of the key for /proc/keys.
 */
// static void public_key_describe(const struct key *asymmetric_key,
//				struct seq_file *m)
//{
//	struct public_key *key = asymmetric_key->payload.data[asym_crypto];
//
//	if (key)
//		seq_printf(m, "%s.%s", key->id_type, key->pkey_algo);
// }

/*
 * Destroy a public key algorithm key.
 */
void
public_key_free(struct public_key *key)
{
    if (key)
    {
        kfree(key->key);
        kfree(key);
    }
}
// EXPORT_SYMBOL_GPL(public_key_free);

/*
 * Destroy a public key algorithm key.
 */
// static void public_key_destroy(void *payload0, void *payload3)
//{
//	public_key_free(payload0);
//	public_key_signature_free(payload3);
// }

// struct public_key_completion {
//	struct completion completion;
//	int err;
// };
//
// static void public_key_verify_done(struct crypto_async_request *req, int err)
//{
//	struct public_key_completion *compl = req->data;
//
//	if (err == -EINPROGRESS)
//		return;
//
//	compl->err = err;
//	complete(&compl->completion);
// }

/*
 * Verify a signature using a public key.
 */
// int public_key_verify_signature(const struct public_key *pkey,
//				const struct public_key_signature *sig)
//{
//	struct public_key_completion compl;
//	struct crypto_akcipher *tfm;
//	struct akcipher_request *req;
//	struct scatterlist sig_sg, digest_sg;
//	const char *alg_name;
//	char alg_name_buf[CRYPTO_MAX_ALG_NAME];
//	void *output;
//	unsigned int outlen;
//	int ret = -ENOMEM;
//
//	pr_devel("==>%s()\n", __func__);
//
//	BUG_ON(!pkey);
//	BUG_ON(!sig);
//	BUG_ON(!sig->s);
//
//	if (!sig->digest)
//		return -ENOPKG;
//
//	alg_name = sig->pkey_algo;
//	if (strcmp(sig->pkey_algo, "rsa") == 0) {
//		/* The data wangled by the RSA algorithm is typically padded
//		 * and encoded in some manner, such as EMSA-PKCS1-1_5 [RFC3447
//		 * sec 8.2].
//		 */
//		if (snprintf(alg_name_buf, CRYPTO_MAX_ALG_NAME,
//			     "pkcs1pad(rsa,%s)", sig->hash_algo
//			     ) >= CRYPTO_MAX_ALG_NAME)
//			return -EINVAL;
//		alg_name = alg_name_buf;
//	}
//
//	tfm = crypto_alloc_akcipher(alg_name, 0, 0);
//	if (IS_ERR(tfm))
//		return PTR_ERR(tfm);
//
//	req = akcipher_request_alloc(tfm, GFP_KERNEL);
//	if (!req)
//		goto error_free_tfm;
//
//	ret = crypto_akcipher_set_pub_key(tfm, pkey->key, pkey->keylen);
//	if (ret)
//		goto error_free_req;
//
//	ret = -ENOMEM;
//	outlen = crypto_akcipher_maxsize(tfm);
//	output = kmalloc(outlen, GFP_KERNEL);
//	if (!output)
//		goto error_free_req;
//
//	sg_init_one(&sig_sg, sig->s, sig->s_size);
//	sg_init_one(&digest_sg, output, outlen);
//	akcipher_request_set_crypt(req, &sig_sg, &digest_sg, sig->s_size,
//				   outlen);
//	init_completion(&compl.completion);
//	akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
//				      CRYPTO_TFM_REQ_MAY_SLEEP,
//				      public_key_verify_done, &compl);
//
//	/* Perform the verification calculation.  This doesn't actually do the
//	 * verification, but rather calculates the hash expected by the
//	 * signature and returns that to us.
//	 */
//	ret = crypto_akcipher_verify(req);
//	if ((ret == -EINPROGRESS) || (ret == -EBUSY)) {
//		wait_for_completion(&compl.completion);
//		ret = compl.err;
//	}
//	if (ret < 0)
//		goto out_free_output;
//
//	/* Do the actual verification step. */
//	if (req->dst_len != sig->digest_size ||
//	    memcmp(sig->digest, output, sig->digest_size) != 0)
//		ret = -EKEYREJECTED;
//
// out_free_output:
//	kfree(output);
// error_free_req:
//	akcipher_request_free(req);
// error_free_tfm:
//	crypto_free_akcipher(tfm);
//	pr_devel("<==%s() = %d\n", __func__, ret);
//	return ret;
// }
// EXPORT_SYMBOL_GPL(public_key_verify_signature);
//
// static int public_key_verify_signature_2(const struct key *key,
//					 const struct public_key_signature *sig)
//{
//	const struct public_key *pk = key->payload.data[asym_crypto];
//	return public_key_verify_signature(pk, sig);
// }

/*
 * Public key algorithm asymmetric key subtype
 */
// struct asymmetric_key_subtype public_key_subtype = {
//	.owner			= THIS_MODULE,
//	.name			= "public_key",
//	.name_len		= sizeof("public_key") - 1,
//	.describe		= public_key_describe,
//	.destroy		= public_key_destroy,
//	.verify_signature	= public_key_verify_signature_2,
// };
// EXPORT_SYMBOL_GPL(public_key_subtype);