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

Stefan Berger
2024-03-01T20:48:02Z

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@linux.ibm.com>
>> ---
>> 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