crypto/rsa-pkcs1pad.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * RSA padding templates.
  *
  * Copyright (c) 2015  Intel Corporation
  */

 #include <crypto/algapi.h>
 #include <crypto/akcipher.h>
 #include <crypto/internal/akcipher.h>
 #include <crypto/internal/rsa.h>
 #include <linux/err.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/random.h>
 #include <linux/scatterlist.h>

 struct pkcs1pad_ctx {
 	struct crypto_akcipher *child;
 	unsigned int key_size;
 };

 struct pkcs1pad_inst_ctx {
 	struct crypto_akcipher_spawn spawn;
 };

 struct pkcs1pad_request {
 	struct scatterlist in_sg[2], out_sg[1];
 	uint8_t *in_buf, *out_buf;
 	struct akcipher_request child_req;
 };

 static int pkcs1pad_set_pub_key(struct crypto_akcipher *tfm, const void *key,
 		unsigned int keylen)
 {
 	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);

 	return rsa_set_key(ctx->child, &ctx->key_size, RSA_PUB, key, keylen);
 }

 static int pkcs1pad_set_priv_key(struct crypto_akcipher *tfm, const void *key,
 		unsigned int keylen)
 {
 	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);

 	return rsa_set_key(ctx->child, &ctx->key_size, RSA_PRIV, key, keylen);
 }

 static unsigned int pkcs1pad_get_max_size(struct crypto_akcipher *tfm)
 {
 	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);

 	/*
 	 * The maximum destination buffer size for the encrypt operation
 	 * will be the same as for RSA, even though it's smaller for
 	 * decrypt.
 	 */

 	return ctx->key_size;
 }

 static void pkcs1pad_sg_set_buf(struct scatterlist *sg, void *buf, size_t len,
 		struct scatterlist *next)
 {
 	int nsegs = next ? 2 : 1;

 	sg_init_table(sg, nsegs);
 	sg_set_buf(sg, buf, len);

 	if (next)
 		sg_chain(sg, nsegs, next);
 }

 static int pkcs1pad_encrypt_complete(struct akcipher_request *req, int err)
 {
 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
 	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
 	struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
 	unsigned int pad_len;
 	unsigned int len;
 	u8 *out_buf;

 	if (err)
 		goto out;

 	len = req_ctx->child_req.dst_len;
 	pad_len = ctx->key_size - len;

 	/* Four billion to one */
 	if (likely(!pad_len))
 		goto out;

 	out_buf = kzalloc(ctx->key_size, GFP_ATOMIC);
 	err = -ENOMEM;
 	if (!out_buf)
 		goto out;

 	sg_copy_to_buffer(req->dst, sg_nents_for_len(req->dst, len),
 			  out_buf + pad_len, len);
 	sg_copy_from_buffer(req->dst,
 			    sg_nents_for_len(req->dst, ctx->key_size),
 			    out_buf, ctx->key_size);
 	kfree_sensitive(out_buf);

 out:
 	req->dst_len = ctx->key_size;

 	kfree(req_ctx->in_buf);

 	return err;
 }

 static void pkcs1pad_encrypt_complete_cb(void *data, int err)
 {
 	struct akcipher_request *req = data;

 	if (err == -EINPROGRESS)
 		goto out;

 	err = pkcs1pad_encrypt_complete(req, err);

 out:
 	akcipher_request_complete(req, err);
 }

 static int pkcs1pad_encrypt(struct akcipher_request *req)
 {
 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
 	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
 	struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
 	int err;
 	unsigned int i, ps_end;

 	if (!ctx->key_size)
 		return -EINVAL;

 	if (req->src_len > ctx->key_size - 11)
 		return -EOVERFLOW;

 	if (req->dst_len < ctx->key_size) {
 		req->dst_len = ctx->key_size;
 		return -EOVERFLOW;
 	}

 	req_ctx->in_buf = kmalloc(ctx->key_size - 1 - req->src_len,
 				  GFP_KERNEL);
 	if (!req_ctx->in_buf)
 		return -ENOMEM;

 	ps_end = ctx->key_size - req->src_len - 2;
 	req_ctx->in_buf[0] = 0x02;
 	for (i = 1; i < ps_end; i++)
 		req_ctx->in_buf[i] = get_random_u32_inclusive(1, 255);
 	req_ctx->in_buf[ps_end] = 0x00;

 	pkcs1pad_sg_set_buf(req_ctx->in_sg, req_ctx->in_buf,
 			ctx->key_size - 1 - req->src_len, req->src);

 	akcipher_request_set_tfm(&req_ctx->child_req, ctx->child);
 	akcipher_request_set_callback(&req_ctx->child_req, req->base.flags,
 			pkcs1pad_encrypt_complete_cb, req);

 	/* Reuse output buffer */
 	akcipher_request_set_crypt(&req_ctx->child_req, req_ctx->in_sg,
 				   req->dst, ctx->key_size - 1, req->dst_len);

 	err = crypto_akcipher_encrypt(&req_ctx->child_req);
 	if (err != -EINPROGRESS && err != -EBUSY)
 		return pkcs1pad_encrypt_complete(req, err);

 	return err;
 }

 static int pkcs1pad_decrypt_complete(struct akcipher_request *req, int err)
 {
 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
 	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
 	struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
 	unsigned int dst_len;
 	unsigned int pos;
 	u8 *out_buf;

 	if (err)
 		goto done;

 	err = -EINVAL;
 	dst_len = req_ctx->child_req.dst_len;
 	if (dst_len < ctx->key_size - 1)
 		goto done;

 	out_buf = req_ctx->out_buf;
 	if (dst_len == ctx->key_size) {
 		if (out_buf[0] != 0x00)
 			/* Decrypted value had no leading 0 byte */
 			goto done;

 		dst_len--;
 		out_buf++;
 	}

 	if (out_buf[0] != 0x02)
 		goto done;

 	for (pos = 1; pos < dst_len; pos++)
 		if (out_buf[pos] == 0x00)
 			break;
 	if (pos < 9 || pos == dst_len)
 		goto done;
 	pos++;

 	err = 0;

 	if (req->dst_len < dst_len - pos)
 		err = -EOVERFLOW;
 	req->dst_len = dst_len - pos;

 	if (!err)
 		sg_copy_from_buffer(req->dst,
 				sg_nents_for_len(req->dst, req->dst_len),
 				out_buf + pos, req->dst_len);

 done:
 	kfree_sensitive(req_ctx->out_buf);

 	return err;
 }

 static void pkcs1pad_decrypt_complete_cb(void *data, int err)
 {
 	struct akcipher_request *req = data;

 	if (err == -EINPROGRESS)
 		goto out;

 	err = pkcs1pad_decrypt_complete(req, err);

 out:
 	akcipher_request_complete(req, err);
 }

 static int pkcs1pad_decrypt(struct akcipher_request *req)
 {
 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
 	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
 	struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
 	int err;

 	if (!ctx->key_size || req->src_len != ctx->key_size)
 		return -EINVAL;

 	req_ctx->out_buf = kmalloc(ctx->key_size, GFP_KERNEL);
 	if (!req_ctx->out_buf)
 		return -ENOMEM;

 	pkcs1pad_sg_set_buf(req_ctx->out_sg, req_ctx->out_buf,
 			    ctx->key_size, NULL);

 	akcipher_request_set_tfm(&req_ctx->child_req, ctx->child);
 	akcipher_request_set_callback(&req_ctx->child_req, req->base.flags,
 			pkcs1pad_decrypt_complete_cb, req);

 	/* Reuse input buffer, output to a new buffer */
 	akcipher_request_set_crypt(&req_ctx->child_req, req->src,
 				   req_ctx->out_sg, req->src_len,
 				   ctx->key_size);

 	err = crypto_akcipher_decrypt(&req_ctx->child_req);
 	if (err != -EINPROGRESS && err != -EBUSY)
 		return pkcs1pad_decrypt_complete(req, err);

 	return err;
 }

 static int pkcs1pad_init_tfm(struct crypto_akcipher *tfm)
 {
 	struct akcipher_instance *inst = akcipher_alg_instance(tfm);
 	struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst);
 	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
 	struct crypto_akcipher *child_tfm;

 	child_tfm = crypto_spawn_akcipher(&ictx->spawn);
 	if (IS_ERR(child_tfm))
 		return PTR_ERR(child_tfm);

 	ctx->child = child_tfm;

 	akcipher_set_reqsize(tfm, sizeof(struct pkcs1pad_request) +
 				  crypto_akcipher_reqsize(child_tfm));

 	return 0;
 }

 static void pkcs1pad_exit_tfm(struct crypto_akcipher *tfm)
 {
 	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);

 	crypto_free_akcipher(ctx->child);
 }

 static void pkcs1pad_free(struct akcipher_instance *inst)
 {
 	struct pkcs1pad_inst_ctx *ctx = akcipher_instance_ctx(inst);
 	struct crypto_akcipher_spawn *spawn = &ctx->spawn;

 	crypto_drop_akcipher(spawn);
 	kfree(inst);
 }

 static int pkcs1pad_create(struct crypto_template *tmpl, struct rtattr **tb)
 {
 	u32 mask;
 	struct akcipher_instance *inst;
 	struct pkcs1pad_inst_ctx *ctx;
 	struct akcipher_alg *rsa_alg;
 	int err;

 	err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AKCIPHER, &mask);
 	if (err)
 		return err;

 	inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
 	if (!inst)
 		return -ENOMEM;

 	ctx = akcipher_instance_ctx(inst);

 	err = crypto_grab_akcipher(&ctx->spawn, akcipher_crypto_instance(inst),
 				   crypto_attr_alg_name(tb[1]), 0, mask);
 	if (err)
 		goto err_free_inst;

 	rsa_alg = crypto_spawn_akcipher_alg(&ctx->spawn);

 	if (strcmp(rsa_alg->base.cra_name, "rsa") != 0) {
 		err = -EINVAL;
 		goto err_free_inst;
 	}

 	err = -ENAMETOOLONG;
 	if (snprintf(inst->alg.base.cra_name,
 		     CRYPTO_MAX_ALG_NAME, "pkcs1pad(%s)",
 		     rsa_alg->base.cra_name) >= CRYPTO_MAX_ALG_NAME)
 		goto err_free_inst;

 	if (snprintf(inst->alg.base.cra_driver_name,
 		     CRYPTO_MAX_ALG_NAME, "pkcs1pad(%s)",
 		     rsa_alg->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
 		goto err_free_inst;

 	inst->alg.base.cra_priority = rsa_alg->base.cra_priority;
 	inst->alg.base.cra_ctxsize = sizeof(struct pkcs1pad_ctx);

 	inst->alg.init = pkcs1pad_init_tfm;
 	inst->alg.exit = pkcs1pad_exit_tfm;

 	inst->alg.encrypt = pkcs1pad_encrypt;
 	inst->alg.decrypt = pkcs1pad_decrypt;
 	inst->alg.set_pub_key = pkcs1pad_set_pub_key;
 	inst->alg.set_priv_key = pkcs1pad_set_priv_key;
 	inst->alg.max_size = pkcs1pad_get_max_size;

 	inst->free = pkcs1pad_free;

 	err = akcipher_register_instance(tmpl, inst);
 	if (err) {
 err_free_inst:
 		pkcs1pad_free(inst);
 	}
 	return err;
 }

 struct crypto_template rsa_pkcs1pad_tmpl = {
 	.name = "pkcs1pad",
 	.create = pkcs1pad_create,
 	.module = THIS_MODULE,
 };

 MODULE_ALIAS_CRYPTO("pkcs1pad");
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* RSA padding templates.
	*
	* Copyright (c) 2015 Intel Corporation
	*/

	#include <crypto/algapi.h>
	#include <crypto/akcipher.h>
	#include <crypto/internal/akcipher.h>
	#include <crypto/internal/rsa.h>
	#include <linux/err.h>
	#include <linux/init.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/random.h>
	#include <linux/scatterlist.h>

	struct pkcs1pad_ctx {
	struct crypto_akcipher *child;
	unsigned int key_size;
	};

	struct pkcs1pad_inst_ctx {
	struct crypto_akcipher_spawn spawn;
	};

	struct pkcs1pad_request {
	struct scatterlist in_sg[2], out_sg[1];
	uint8_t in_buf, out_buf;
	struct akcipher_request child_req;
	};

	static int pkcs1pad_set_pub_key(struct crypto_akcipher tfm, const void key,
	unsigned int keylen)
	{
	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);

	return rsa_set_key(ctx->child, &ctx->key_size, RSA_PUB, key, keylen);
	}

	static int pkcs1pad_set_priv_key(struct crypto_akcipher tfm, const void key,
	unsigned int keylen)
	{
	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);

	return rsa_set_key(ctx->child, &ctx->key_size, RSA_PRIV, key, keylen);
	}

	static unsigned int pkcs1pad_get_max_size(struct crypto_akcipher *tfm)
	{
	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);

	/*
	* The maximum destination buffer size for the encrypt operation
	* will be the same as for RSA, even though it's smaller for
	* decrypt.
	*/

	return ctx->key_size;
	}

	static void pkcs1pad_sg_set_buf(struct scatterlist sg, void buf, size_t len,
	struct scatterlist *next)
	{
	int nsegs = next ? 2 : 1;

	sg_init_table(sg, nsegs);
	sg_set_buf(sg, buf, len);

	if (next)
	sg_chain(sg, nsegs, next);
	}

	static int pkcs1pad_encrypt_complete(struct akcipher_request *req, int err)
	{
	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
	struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
	unsigned int pad_len;
	unsigned int len;
	u8 *out_buf;

	if (err)
	goto out;

	len = req_ctx->child_req.dst_len;
	pad_len = ctx->key_size - len;

	/* Four billion to one */
	if (likely(!pad_len))
	goto out;

	out_buf = kzalloc(ctx->key_size, GFP_ATOMIC);
	err = -ENOMEM;
	if (!out_buf)
	goto out;

	sg_copy_to_buffer(req->dst, sg_nents_for_len(req->dst, len),
	out_buf + pad_len, len);
	sg_copy_from_buffer(req->dst,
	sg_nents_for_len(req->dst, ctx->key_size),
	out_buf, ctx->key_size);
	kfree_sensitive(out_buf);

	out:
	req->dst_len = ctx->key_size;

	kfree(req_ctx->in_buf);

	return err;
	}

	static void pkcs1pad_encrypt_complete_cb(void *data, int err)
	{
	struct akcipher_request *req = data;

	if (err == -EINPROGRESS)
	goto out;

	err = pkcs1pad_encrypt_complete(req, err);

	out:
	akcipher_request_complete(req, err);
	}

	static int pkcs1pad_encrypt(struct akcipher_request *req)
	{
	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
	struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
	int err;
	unsigned int i, ps_end;

	if (!ctx->key_size)
	return -EINVAL;

	if (req->src_len > ctx->key_size - 11)
	return -EOVERFLOW;

	if (req->dst_len < ctx->key_size) {
	req->dst_len = ctx->key_size;
	return -EOVERFLOW;
	}

	req_ctx->in_buf = kmalloc(ctx->key_size - 1 - req->src_len,
	GFP_KERNEL);
	if (!req_ctx->in_buf)
	return -ENOMEM;

	ps_end = ctx->key_size - req->src_len - 2;
	req_ctx->in_buf[0] = 0x02;
	for (i = 1; i < ps_end; i++)
	req_ctx->in_buf[i] = get_random_u32_inclusive(1, 255);
	req_ctx->in_buf[ps_end] = 0x00;

	pkcs1pad_sg_set_buf(req_ctx->in_sg, req_ctx->in_buf,
	ctx->key_size - 1 - req->src_len, req->src);

	akcipher_request_set_tfm(&req_ctx->child_req, ctx->child);
	akcipher_request_set_callback(&req_ctx->child_req, req->base.flags,
	pkcs1pad_encrypt_complete_cb, req);

	/* Reuse output buffer */
	akcipher_request_set_crypt(&req_ctx->child_req, req_ctx->in_sg,
	req->dst, ctx->key_size - 1, req->dst_len);

	err = crypto_akcipher_encrypt(&req_ctx->child_req);
	if (err != -EINPROGRESS && err != -EBUSY)
	return pkcs1pad_encrypt_complete(req, err);

	return err;
	}

	static int pkcs1pad_decrypt_complete(struct akcipher_request *req, int err)
	{
	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
	struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
	unsigned int dst_len;
	unsigned int pos;
	u8 *out_buf;

	if (err)
	goto done;

	err = -EINVAL;
	dst_len = req_ctx->child_req.dst_len;
	if (dst_len < ctx->key_size - 1)
	goto done;

	out_buf = req_ctx->out_buf;
	if (dst_len == ctx->key_size) {
	if (out_buf[0] != 0x00)
	/* Decrypted value had no leading 0 byte */
	goto done;

	dst_len--;
	out_buf++;
	}

	if (out_buf[0] != 0x02)
	goto done;

	for (pos = 1; pos < dst_len; pos++)
	if (out_buf[pos] == 0x00)
	break;
	if (pos < 9 \|\| pos == dst_len)
	goto done;
	pos++;

	err = 0;

	if (req->dst_len < dst_len - pos)
	err = -EOVERFLOW;
	req->dst_len = dst_len - pos;

	if (!err)
	sg_copy_from_buffer(req->dst,
	sg_nents_for_len(req->dst, req->dst_len),
	out_buf + pos, req->dst_len);

	done:
	kfree_sensitive(req_ctx->out_buf);

	return err;
	}

	static void pkcs1pad_decrypt_complete_cb(void *data, int err)
	{
	struct akcipher_request *req = data;

	if (err == -EINPROGRESS)
	goto out;

	err = pkcs1pad_decrypt_complete(req, err);

	out:
	akcipher_request_complete(req, err);
	}

	static int pkcs1pad_decrypt(struct akcipher_request *req)
	{
	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
	struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
	int err;

	if (!ctx->key_size \|\| req->src_len != ctx->key_size)
	return -EINVAL;

	req_ctx->out_buf = kmalloc(ctx->key_size, GFP_KERNEL);
	if (!req_ctx->out_buf)
	return -ENOMEM;

	pkcs1pad_sg_set_buf(req_ctx->out_sg, req_ctx->out_buf,
	ctx->key_size, NULL);

	akcipher_request_set_tfm(&req_ctx->child_req, ctx->child);
	akcipher_request_set_callback(&req_ctx->child_req, req->base.flags,
	pkcs1pad_decrypt_complete_cb, req);

	/* Reuse input buffer, output to a new buffer */
	akcipher_request_set_crypt(&req_ctx->child_req, req->src,
	req_ctx->out_sg, req->src_len,
	ctx->key_size);

	err = crypto_akcipher_decrypt(&req_ctx->child_req);
	if (err != -EINPROGRESS && err != -EBUSY)
	return pkcs1pad_decrypt_complete(req, err);

	return err;
	}

	static int pkcs1pad_init_tfm(struct crypto_akcipher *tfm)
	{
	struct akcipher_instance *inst = akcipher_alg_instance(tfm);
	struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst);
	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
	struct crypto_akcipher *child_tfm;

	child_tfm = crypto_spawn_akcipher(&ictx->spawn);
	if (IS_ERR(child_tfm))
	return PTR_ERR(child_tfm);

	ctx->child = child_tfm;

	akcipher_set_reqsize(tfm, sizeof(struct pkcs1pad_request) +
	crypto_akcipher_reqsize(child_tfm));

	return 0;
	}

	static void pkcs1pad_exit_tfm(struct crypto_akcipher *tfm)
	{
	struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);

	crypto_free_akcipher(ctx->child);
	}

	static void pkcs1pad_free(struct akcipher_instance *inst)
	{
	struct pkcs1pad_inst_ctx *ctx = akcipher_instance_ctx(inst);
	struct crypto_akcipher_spawn *spawn = &ctx->spawn;

	crypto_drop_akcipher(spawn);
	kfree(inst);
	}

	static int pkcs1pad_create(struct crypto_template tmpl, struct rtattr *tb)
	{
	u32 mask;
	struct akcipher_instance *inst;
	struct pkcs1pad_inst_ctx *ctx;
	struct akcipher_alg *rsa_alg;
	int err;

	err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AKCIPHER, &mask);
	if (err)
	return err;

	inst = kzalloc(sizeof(inst) + sizeof(ctx), GFP_KERNEL);
	if (!inst)
	return -ENOMEM;

	ctx = akcipher_instance_ctx(inst);

	err = crypto_grab_akcipher(&ctx->spawn, akcipher_crypto_instance(inst),
	crypto_attr_alg_name(tb[1]), 0, mask);
	if (err)
	goto err_free_inst;

	rsa_alg = crypto_spawn_akcipher_alg(&ctx->spawn);

	if (strcmp(rsa_alg->base.cra_name, "rsa") != 0) {
	err = -EINVAL;
	goto err_free_inst;
	}

	err = -ENAMETOOLONG;
	if (snprintf(inst->alg.base.cra_name,
	CRYPTO_MAX_ALG_NAME, "pkcs1pad(%s)",
	rsa_alg->base.cra_name) >= CRYPTO_MAX_ALG_NAME)
	goto err_free_inst;

	if (snprintf(inst->alg.base.cra_driver_name,
	CRYPTO_MAX_ALG_NAME, "pkcs1pad(%s)",
	rsa_alg->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
	goto err_free_inst;

	inst->alg.base.cra_priority = rsa_alg->base.cra_priority;
	inst->alg.base.cra_ctxsize = sizeof(struct pkcs1pad_ctx);

	inst->alg.init = pkcs1pad_init_tfm;
	inst->alg.exit = pkcs1pad_exit_tfm;

	inst->alg.encrypt = pkcs1pad_encrypt;
	inst->alg.decrypt = pkcs1pad_decrypt;
	inst->alg.set_pub_key = pkcs1pad_set_pub_key;
	inst->alg.set_priv_key = pkcs1pad_set_priv_key;
	inst->alg.max_size = pkcs1pad_get_max_size;

	inst->free = pkcs1pad_free;

	err = akcipher_register_instance(tmpl, inst);
	if (err) {
	err_free_inst:
	pkcs1pad_free(inst);
	}
	return err;
	}

	struct crypto_template rsa_pkcs1pad_tmpl = {
	.name = "pkcs1pad",
	.create = pkcs1pad_create,
	.module = THIS_MODULE,
	};

	MODULE_ALIAS_CRYPTO("pkcs1pad");