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crypto: hash - Use crypto_request_complete 

Use the crypto_request_complete helper instead of calling the
completion function directly.

This patch also removes the voodoo programming previously used
for unaligned ahash operations and replaces it with a sub-request.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Herbert Xu 2023-02-10 20:20:20 +08:00
parent 700d507805
commit d9588045f5
2 changed files with 72 additions and 103 deletions
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173
crypto/ahash.c
View File

@ -190,133 +190,98 @@ int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
}
EXPORT_SYMBOL_GPL(crypto_ahash_setkey);
static inline unsigned int ahash_align_buffer_size(unsigned len,
unsigned long mask)
{
return len + (mask & ~(crypto_tfm_ctx_alignment() - 1));
}
static int ahash_save_req(struct ahash_request *req, crypto_completion_t cplt)
static int ahash_save_req(struct ahash_request *req, crypto_completion_t cplt,
bool has_state)
{
struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
unsigned long alignmask = crypto_ahash_alignmask(tfm);
unsigned int ds = crypto_ahash_digestsize(tfm);
struct ahash_request_priv *priv;
struct ahash_request *subreq;
unsigned int subreq_size;
unsigned int reqsize;
u8 *result;
gfp_t gfp;
u32 flags;
priv = kmalloc(sizeof(*priv) + ahash_align_buffer_size(ds, alignmask),
(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
GFP_KERNEL : GFP_ATOMIC);
if (!priv)
subreq_size = sizeof(*subreq);
reqsize = crypto_ahash_reqsize(tfm);
reqsize = ALIGN(reqsize, crypto_tfm_ctx_alignment());
subreq_size += reqsize;
subreq_size += ds;
subreq_size += alignmask & ~(crypto_tfm_ctx_alignment() - 1);
flags = ahash_request_flags(req);
gfp = (flags & CRYPTO_TFM_REQ_MAY_SLEEP) ? GFP_KERNEL : GFP_ATOMIC;
subreq = kmalloc(subreq_size, gfp);
if (!subreq)
return -ENOMEM;
/*
* WARNING: Voodoo programming below!
*
* The code below is obscure and hard to understand, thus explanation
* is necessary. See include/crypto/hash.h and include/linux/crypto.h
* to understand the layout of structures used here!
*
* The code here will replace portions of the ORIGINAL request with
* pointers to new code and buffers so the hashing operation can store
* the result in aligned buffer. We will call the modified request
* an ADJUSTED request.
*
* The newly mangled request will look as such:
*
* req {
* .result = ADJUSTED[new aligned buffer]
* .base.complete = ADJUSTED[pointer to completion function]
* .base.data = ADJUSTED[*req (pointer to self)]
* .priv = ADJUSTED[new priv] {
* .result = ORIGINAL(result)
* .complete = ORIGINAL(base.complete)
* .data = ORIGINAL(base.data)
* }
*/
ahash_request_set_tfm(subreq, tfm);
ahash_request_set_callback(subreq, flags, cplt, req);
priv->result = req->result;
priv->complete = req->base.complete;
priv->data = req->base.data;
priv->flags = req->base.flags;
result = (u8 *)(subreq + 1) + reqsize;
result = PTR_ALIGN(result, alignmask + 1);
/*
* WARNING: We do not backup req->priv here! The req->priv
* is for internal use of the Crypto API and the
* user must _NOT_ _EVER_ depend on it's content!
*/
ahash_request_set_crypt(subreq, req->src, result, req->nbytes);
req->result = PTR_ALIGN((u8 *)priv->ubuf, alignmask + 1);
req->base.complete = cplt;
req->base.data = req;
req->priv = priv;
if (has_state) {
void *state;
state = kmalloc(crypto_ahash_statesize(tfm), gfp);
if (!state) {
kfree(subreq);
return -ENOMEM;
}
crypto_ahash_export(req, state);
crypto_ahash_import(subreq, state);
kfree_sensitive(state);
}
req->priv = subreq;
return 0;
}
static void ahash_restore_req(struct ahash_request *req, int err)
{
struct ahash_request_priv *priv = req->priv;
struct ahash_request *subreq = req->priv;
if (!err)
memcpy(priv->result, req->result,
memcpy(req->result, subreq->result,
crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
/* Restore the original crypto request. */
req->result = priv->result;
ahash_request_set_callback(req, priv->flags,
priv->complete, priv->data);
req->priv = NULL;
/* Free the req->priv.priv from the ADJUSTED request. */
kfree_sensitive(priv);
}
static void ahash_notify_einprogress(struct ahash_request *req)
{
struct ahash_request_priv *priv = req->priv;
struct crypto_async_request oreq;
oreq.data = priv->data;
priv->complete(&oreq, -EINPROGRESS);
kfree_sensitive(subreq);
}
static void ahash_op_unaligned_done(struct crypto_async_request *req, int err)
{
struct ahash_request *areq = req->data;
if (err == -EINPROGRESS) {
ahash_notify_einprogress(areq);
return;
}
/*
* Restore the original request, see ahash_op_unaligned() for what
* goes where.
*
* The "struct ahash_request *req" here is in fact the "req.base"
* from the ADJUSTED request from ahash_op_unaligned(), thus as it
* is a pointer to self, it is also the ADJUSTED "req" .
*/
if (err == -EINPROGRESS)
goto out;
/* First copy req->result into req->priv.result */
ahash_restore_req(areq, err);
out:
/* Complete the ORIGINAL request. */
areq->base.complete(&areq->base, err);
ahash_request_complete(areq, err);
}
static int ahash_op_unaligned(struct ahash_request *req,
int (*op)(struct ahash_request *))
int (*op)(struct ahash_request *),
bool has_state)
{
int err;
err = ahash_save_req(req, ahash_op_unaligned_done);
err = ahash_save_req(req, ahash_op_unaligned_done, has_state);
if (err)
return err;
err = op(req);
err = op(req->priv);
if (err == -EINPROGRESS || err == -EBUSY)
return err;
@ -326,13 +291,14 @@ static int ahash_op_unaligned(struct ahash_request *req,
}
static int crypto_ahash_op(struct ahash_request *req,
int (*op)(struct ahash_request *))
int (*op)(struct ahash_request *),
bool has_state)
{
struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
unsigned long alignmask = crypto_ahash_alignmask(tfm);
if ((unsigned long)req->result & alignmask)
return ahash_op_unaligned(req, op);
return ahash_op_unaligned(req, op, has_state);
return op(req);
}
@ -345,7 +311,7 @@ int crypto_ahash_final(struct ahash_request *req)
int ret;
crypto_stats_get(alg);
ret = crypto_ahash_op(req, crypto_ahash_reqtfm(req)->final);
ret = crypto_ahash_op(req, crypto_ahash_reqtfm(req)->final, true);
crypto_stats_ahash_final(nbytes, ret, alg);
return ret;
}
@ -359,7 +325,7 @@ int crypto_ahash_finup(struct ahash_request *req)
int ret;
crypto_stats_get(alg);
ret = crypto_ahash_op(req, crypto_ahash_reqtfm(req)->finup);
ret = crypto_ahash_op(req, crypto_ahash_reqtfm(req)->finup, true);
crypto_stats_ahash_final(nbytes, ret, alg);
return ret;
}
@ -376,7 +342,7 @@ int crypto_ahash_digest(struct ahash_request *req)
if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
ret = -ENOKEY;
else
ret = crypto_ahash_op(req, tfm->digest);
ret = crypto_ahash_op(req, tfm->digest, false);
crypto_stats_ahash_final(nbytes, ret, alg);
return ret;
}
@ -391,17 +357,19 @@ static void ahash_def_finup_done2(struct crypto_async_request *req, int err)
ahash_restore_req(areq, err);
areq->base.complete(&areq->base, err);
ahash_request_complete(areq, err);
}
static int ahash_def_finup_finish1(struct ahash_request *req, int err)
{
struct ahash_request *subreq = req->priv;
if (err)
goto out;
req->base.complete = ahash_def_finup_done2;
subreq->base.complete = ahash_def_finup_done2;
err = crypto_ahash_reqtfm(req)->final(req);
err = crypto_ahash_reqtfm(req)->final(subreq);
if (err == -EINPROGRESS || err == -EBUSY)
return err;
@ -413,19 +381,20 @@ out:
static void ahash_def_finup_done1(struct crypto_async_request *req, int err)
{
struct ahash_request *areq = req->data;
struct ahash_request *subreq;
if (err == -EINPROGRESS) {
ahash_notify_einprogress(areq);
return;
}
if (err == -EINPROGRESS)
goto out;
areq->base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
subreq = areq->priv;
subreq->base.flags &= CRYPTO_TFM_REQ_MAY_BACKLOG;
err = ahash_def_finup_finish1(areq, err);
if (areq->priv)
if (err == -EINPROGRESS || err == -EBUSY)
return;
areq->base.complete(&areq->base, err);
out:
ahash_request_complete(areq, err);
}
static int ahash_def_finup(struct ahash_request *req)
@ -433,11 +402,11 @@ static int ahash_def_finup(struct ahash_request *req)
struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
int err;
err = ahash_save_req(req, ahash_def_finup_done1);
err = ahash_save_req(req, ahash_def_finup_done1, true);
if (err)
return err;
err = tfm->update(req);
err = tfm->update(req->priv);
if (err == -EINPROGRESS || err == -EBUSY)
return err;

2
include/crypto/internal/hash.h
View File

@ -199,7 +199,7 @@ static inline void *ahash_request_ctx_dma(struct ahash_request *req)
static inline void ahash_request_complete(struct ahash_request *req, int err)
{
req->base.complete(&req->base, err);
crypto_request_complete(&req->base, err);
}
static inline u32 ahash_request_flags(struct ahash_request *req)