Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 6350449f authored by Herbert Xu's avatar Herbert Xu
Browse files

crypto: aead - Add common IV generation code 



This patch adds some common IV generation code currently duplicated
by seqiv and echainiv.  For example, the setkey and setauthsize
functions are completely identical.

Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent b455eb80

crypto/aead.c

+202 −3
Original line number Diff line number Diff line
@@ -12,7 +12,7 @@ 
 *

 */



#include <crypto/internal/aead.h>

#include <crypto/internal/geniv.h>

#include <crypto/scatterwalk.h>

#include <linux/err.h>

#include <linux/init.h>
@@ -27,6 +27,14 @@ 


#include "internal.h"



struct compat_request_ctx {

	struct scatterlist src[2];

	struct scatterlist dst[2];

	struct scatterlist ivbuf[2];

	struct scatterlist *ivsg;

	struct aead_givcrypt_request subreq;

};



static int aead_null_givencrypt(struct aead_givcrypt_request *req);

static int aead_null_givdecrypt(struct aead_givcrypt_request *req);
@@ -373,6 +381,185 @@ static int crypto_grab_nivaead(struct crypto_aead_spawn *spawn, 
	return crypto_grab_spawn(&spawn->base, name, type, mask);

}



static int aead_geniv_setkey(struct crypto_aead *tfm,

			     const u8 *key, unsigned int keylen)

{

	struct aead_geniv_ctx *ctx = crypto_aead_ctx(tfm);



	return crypto_aead_setkey(ctx->child, key, keylen);

}



static int aead_geniv_setauthsize(struct crypto_aead *tfm,

				  unsigned int authsize)

{

	struct aead_geniv_ctx *ctx = crypto_aead_ctx(tfm);



	return crypto_aead_setauthsize(ctx->child, authsize);

}



static void compat_encrypt_complete2(struct aead_request *req, int err)

{

	struct compat_request_ctx *rctx = aead_request_ctx(req);

	struct aead_givcrypt_request *subreq = &rctx->subreq;

	struct crypto_aead *geniv;



	if (err == -EINPROGRESS)

		return;



	if (err)

		goto out;



	geniv = crypto_aead_reqtfm(req);

	scatterwalk_map_and_copy(subreq->giv, rctx->ivsg, 0,

				 crypto_aead_ivsize(geniv), 1);



out:

	kzfree(subreq->giv);

}



static void compat_encrypt_complete(struct crypto_async_request *base, int err)

{

	struct aead_request *req = base->data;



	compat_encrypt_complete2(req, err);

	aead_request_complete(req, err);

}



static int compat_encrypt(struct aead_request *req)

{

	struct crypto_aead *geniv = crypto_aead_reqtfm(req);

	struct aead_geniv_ctx *ctx = crypto_aead_ctx(geniv);

	struct compat_request_ctx *rctx = aead_request_ctx(req);

	struct aead_givcrypt_request *subreq = &rctx->subreq;

	unsigned int ivsize = crypto_aead_ivsize(geniv);

	struct scatterlist *src, *dst;

	crypto_completion_t compl;

	void *data;

	u8 *info;

	__be64 seq;

	int err;



	if (req->cryptlen < ivsize)

		return -EINVAL;



	compl = req->base.complete;

	data = req->base.data;



	rctx->ivsg = scatterwalk_ffwd(rctx->ivbuf, req->dst, req->assoclen);

	info = PageHighMem(sg_page(rctx->ivsg)) ? NULL : sg_virt(rctx->ivsg);



	if (!info) {

		info = kmalloc(ivsize, req->base.flags &

				       CRYPTO_TFM_REQ_MAY_SLEEP ? GFP_KERNEL:

								  GFP_ATOMIC);

		if (!info)

			return -ENOMEM;



		compl = compat_encrypt_complete;

		data = req;

	}



	memcpy(&seq, req->iv + ivsize - sizeof(seq), sizeof(seq));



	src = scatterwalk_ffwd(rctx->src, req->src, req->assoclen + ivsize);

	dst = req->src == req->dst ?

	      src : scatterwalk_ffwd(rctx->dst, rctx->ivsg, ivsize);



	aead_givcrypt_set_tfm(subreq, ctx->child);

	aead_givcrypt_set_callback(subreq, req->base.flags,

				   req->base.complete, req->base.data);

	aead_givcrypt_set_crypt(subreq, src, dst,

				req->cryptlen - ivsize, req->iv);

	aead_givcrypt_set_assoc(subreq, req->src, req->assoclen);

	aead_givcrypt_set_giv(subreq, info, be64_to_cpu(seq));



	err = crypto_aead_givencrypt(subreq);

	if (unlikely(PageHighMem(sg_page(rctx->ivsg))))

		compat_encrypt_complete2(req, err);

	return err;

}



static int compat_decrypt(struct aead_request *req)

{

	struct crypto_aead *geniv = crypto_aead_reqtfm(req);

	struct aead_geniv_ctx *ctx = crypto_aead_ctx(geniv);

	struct compat_request_ctx *rctx = aead_request_ctx(req);

	struct aead_request *subreq = &rctx->subreq.areq;

	unsigned int ivsize = crypto_aead_ivsize(geniv);

	struct scatterlist *src, *dst;

	crypto_completion_t compl;

	void *data;



	if (req->cryptlen < ivsize)

		return -EINVAL;



	aead_request_set_tfm(subreq, ctx->child);



	compl = req->base.complete;

	data = req->base.data;



	src = scatterwalk_ffwd(rctx->src, req->src, req->assoclen + ivsize);

	dst = req->src == req->dst ?

	      src : scatterwalk_ffwd(rctx->dst, req->dst,

				     req->assoclen + ivsize);



	aead_request_set_callback(subreq, req->base.flags, compl, data);

	aead_request_set_crypt(subreq, src, dst,

			       req->cryptlen - ivsize, req->iv);

	aead_request_set_assoc(subreq, req->src, req->assoclen);



	scatterwalk_map_and_copy(req->iv, req->src, req->assoclen, ivsize, 0);



	return crypto_aead_decrypt(subreq);

}



static int compat_encrypt_first(struct aead_request *req)

{

	struct crypto_aead *geniv = crypto_aead_reqtfm(req);

	struct aead_geniv_ctx *ctx = crypto_aead_ctx(geniv);

	int err = 0;



	spin_lock_bh(&ctx->lock);

	if (geniv->encrypt != compat_encrypt_first)

		goto unlock;



	geniv->encrypt = compat_encrypt;



unlock:

	spin_unlock_bh(&ctx->lock);



	if (err)

		return err;



	return compat_encrypt(req);

}



static int aead_geniv_init_compat(struct crypto_tfm *tfm)

{

	struct crypto_aead *geniv = __crypto_aead_cast(tfm);

	struct aead_geniv_ctx *ctx = crypto_aead_ctx(geniv);

	int err;



	spin_lock_init(&ctx->lock);



	crypto_aead_set_reqsize(geniv, sizeof(struct compat_request_ctx));



	err = aead_geniv_init(tfm);



	ctx->child = geniv->child;

	geniv->child = geniv;



	return err;

}



static void aead_geniv_exit_compat(struct crypto_tfm *tfm)

{

	struct crypto_aead *geniv = __crypto_aead_cast(tfm);

	struct aead_geniv_ctx *ctx = crypto_aead_ctx(geniv);



	crypto_free_aead(ctx->child);

}



struct aead_instance *aead_geniv_alloc(struct crypto_template *tmpl,

				       struct rtattr **tb, u32 type, u32 mask)

{
@@ -407,7 +594,9 @@ struct aead_instance *aead_geniv_alloc(struct crypto_template *tmpl, 
	mask |= crypto_requires_sync(algt->type, algt->mask);



	crypto_set_aead_spawn(spawn, aead_crypto_instance(inst));

	err = crypto_grab_nivaead(spawn, name, type, mask);

	err = (algt->mask & CRYPTO_ALG_GENIV) ?

	      crypto_grab_nivaead(spawn, name, type, mask) :

	      crypto_grab_aead(spawn, name, type, mask);

	if (err)

		goto err_free_inst;
@@ -417,7 +606,7 @@ struct aead_instance *aead_geniv_alloc(struct crypto_template *tmpl, 
	maxauthsize = crypto_aead_alg_maxauthsize(alg);



	err = -EINVAL;

	if (!ivsize)

	if (ivsize < sizeof(u64))

		goto err_drop_alg;



	/*
@@ -471,10 +660,20 @@ struct aead_instance *aead_geniv_alloc(struct crypto_template *tmpl, 
	inst->alg.base.cra_priority = alg->base.cra_priority;

	inst->alg.base.cra_blocksize = alg->base.cra_blocksize;

	inst->alg.base.cra_alignmask = alg->base.cra_alignmask;

	inst->alg.base.cra_ctxsize = sizeof(struct aead_geniv_ctx);



	inst->alg.setkey = aead_geniv_setkey;

	inst->alg.setauthsize = aead_geniv_setauthsize;



	inst->alg.ivsize = ivsize;

	inst->alg.maxauthsize = maxauthsize;



	inst->alg.encrypt = compat_encrypt_first;

	inst->alg.decrypt = compat_decrypt;



	inst->alg.base.cra_init = aead_geniv_init_compat;

	inst->alg.base.cra_exit = aead_geniv_exit_compat;



out:

	return inst;

include/crypto/internal/geniv.h

0 → 100644
+24 −0
Original line number Diff line number Diff line 
/*

 * geniv: IV generation

 *

 * Copyright (c) 2015 Herbert Xu <herbert@gondor.apana.org.au>

 *

 * 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.

 *

 */



#ifndef _CRYPTO_INTERNAL_GENIV_H

#define _CRYPTO_INTERNAL_GENIV_H



#include <crypto/internal/aead.h>

#include <linux/spinlock.h>



struct aead_geniv_ctx {

	spinlock_t lock;

	struct crypto_aead *child;

};



#endif	/* _CRYPTO_INTERNAL_GENIV_H */