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: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Herbert Xu 2015-05-27 14:37:30 +08:00
parent b455eb80f1
commit 6350449fbf
2 changed files with 226 additions and 3 deletions

View File

@ -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;

View File

@ -0,0 +1,24 @@
/*
* 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 */