Messages in this thread | ![/](/images/icornerl.gif) | | Date | Thu, 29 Feb 2024 12:20:08 -0500 | Subject | Re: [PATCH v3 01/10] crypto: ecdsa - Convert byte arrays with key coordinates to digits | From | Stefan Berger <> |
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On 2/29/24 11:48, Lukas Wunner wrote: > On Thu, Feb 29, 2024 at 09:57:30AM -0500, Stefan Berger wrote: >> static inline void ecc_digits_from_bytes(const u8 *in, unsigned int nbytes, >> u64 *out, unsigned int ndigits) >> { >> unsigned int o = nbytes & 7; >> u64 msd = 0; >> size_t i; >> >> if (o == 0) { >> ecc_swap_digits(in, out, ndigits); >> } else { >> for (i = 0; i < o; i++) >> msd = (msd << 8) | in[i]; >> out[ndigits - 1] = msd; >> ecc_swap_digits(&in[o], out, ndigits - 1); >> } >> } > > Might be beneficial to add a code comment explaining the else-branch > is for curves with key length not a multiple of 64 bits (such as NIST P521).
Will do. I am also using this here now since it's safer: ecc_swap_digits(&in[o], out, (nbytes - o) >> 3);
Stefan
> > Otherwise LGTM, thanks! > > Lukas
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