Re: [PATCH v4 09/12] crypto: ecdsa - Rename keylen to bufsize where necessary

[Stefan Berger]

On 3/1/24 15:41, Jarkko Sakkinen wrote:
> On Fri Mar 1, 2024 at 4:20 AM EET, Stefan Berger wrote:
> > In some cases the name keylen does not reflect the purpose of the variable
> > anymore once NIST P521 is used but it is the size of the buffer. There-
> > for, rename keylen to bufsize where appropriate.
> >
> > Signed-off-by: Stefan Berger <stefanb@xxxxxxxxxxxxx>
> > ---
> >   crypto/ecdsa.c | 12 ++++++------
> >   1 file changed, 6 insertions(+), 6 deletions(-)
> >
> > diff --git a/crypto/ecdsa.c b/crypto/ecdsa.c
> > index 4daefb40c37a..4e847b59622a 100644
> > --- a/crypto/ecdsa.c
> > +++ b/crypto/ecdsa.c
> > @@ -35,8 +35,8 @@ struct ecdsa_signature_ctx {
> >   static int ecdsa_get_signature_rs(u64 *dest, size_t hdrlen, unsigned char tag,
> >   				  const void *value, size_t vlen, unsigned int ndigits)
> >   {
> > -	size_t keylen = ndigits * sizeof(u64);
> > -	ssize_t diff = vlen - keylen;
> > +	size_t bufsize = ndigits * sizeof(u64);
>
> why not just "* 8"? using sizeof here makes this function only unreadable.

'unreadable' is a 'strong' word ...

# grep -r -E "ndigits \*" crypto/ | grep sizeof
crypto/ecrdsa.c:            req->dst_len != ctx->curve->g.ndigits * 
sizeof(u64) ||
crypto/ecrdsa.c:        vli_from_be64(r, sig + ndigits * sizeof(u64), 
ndigits);
crypto/ecrdsa.c:            ctx->curve->g.ndigits * sizeof(u64) != 
ctx->digest_len)
crypto/ecrdsa.c:            ctx->key_len != ctx->curve->g.ndigits * 
sizeof(u64) * 2)
crypto/ecrdsa.c:        vli_from_le64(ctx->pub_key.y, ctx->key + ndigits 
* sizeof(u64),
crypto/ecrdsa.c:        return ctx->pub_key.ndigits * sizeof(u64);
crypto/ecc.c:   size_t len = ndigits * sizeof(u64);
crypto/ecc.c:   num_bits = sizeof(u64) * ndigits * 8 + 1;
crypto/ecdsa.c: size_t keylen = ndigits * sizeof(u64);
crypto/ecdsa.c: size_t keylen = ctx->curve->g.ndigits * sizeof(u64);

   Stefan