| Message ID | 20240223204149.4055630-3-stefanb@linux.ibm.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Add support for NIST P521 to ecdsa | expand |
On Fri, Feb 23, 2024 at 03:41:41PM -0500, Stefan Berger wrote: > @@ -239,7 +239,7 @@ static int ecdsa_set_pub_key(struct crypto_akcipher *tfm, const void *key, unsig > keylen--; > digitlen = keylen >> 1; > > - ndigits = digitlen / sizeof(u64); > + ndigits = DIV_ROUND_UP(digitlen, sizeof(u64)); > if (ndigits != ctx->curve->g.ndigits) > return -EINVAL; This deletes a line inserted by the preceding patch in the series. I'd prefer just squashing the two patches together. Thanks, Lukas
On 2/29/24 04:16, Lukas Wunner wrote: > On Fri, Feb 23, 2024 at 03:41:41PM -0500, Stefan Berger wrote: >> @@ -239,7 +239,7 @@ static int ecdsa_set_pub_key(struct crypto_akcipher *tfm, const void *key, unsig >> keylen--; >> digitlen = keylen >> 1; >> >> - ndigits = digitlen / sizeof(u64); >> + ndigits = DIV_ROUND_UP(digitlen, sizeof(u64)); >> if (ndigits != ctx->curve->g.ndigits) >> return -EINVAL; > > This deletes a line inserted by the preceding patch in the series. > I'd prefer just squashing the two patches together. > Hm, I moved this part here into 1/10 and left he other hunk in 2/10 since they deal with slightly different issues. Stefan > Thanks, > > Lukas
diff --git a/crypto/ecdsa.c b/crypto/ecdsa.c index ba8fb76fd165..64e1e69d53ba 100644 --- a/crypto/ecdsa.c +++ b/crypto/ecdsa.c @@ -230,7 +230,7 @@ static int ecdsa_set_pub_key(struct crypto_akcipher *tfm, const void *key, unsig if (ret < 0) return ret; - if (keylen < 1 || (((keylen - 1) >> 1) % sizeof(u64)) != 0) + if (keylen < 1 || ((keylen - 1) & 1) != 0) return -EINVAL; /* we only accept uncompressed format indicated by '4' */ if (d[0] != 4) @@ -239,7 +239,7 @@ static int ecdsa_set_pub_key(struct crypto_akcipher *tfm, const void *key, unsig keylen--; digitlen = keylen >> 1; - ndigits = digitlen / sizeof(u64); + ndigits = DIV_ROUND_UP(digitlen, sizeof(u64)); if (ndigits != ctx->curve->g.ndigits) return -EINVAL;
In preparation for support of NIST P521, adjust the basic tests on the length of the provided key parameters to only ensure that the length of the x plus y coordinates parameter array is not an odd number and that each coordinate fits into an array of 'ndigits' digits. Mathematical tests on the key's parameters are then done in ecc_is_pubkey_valid_full rejecting invalid keys. The change is necessary since NIST P521 keys do not have keys with coordinates that each fully require 'full' digits (= u64), unlike NIST P192/256/384 that all require multiple 'full' digits. Signed-off-by: Stefan Berger <stefanb@linux.ibm.com> --- crypto/ecdsa.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)