From 0f419a55fe9f5a7245d4043c9b5f89d43c7a4491 Mon Sep 17 00:00:00 2001 From: Stefan Berger Date: Thu, 4 Apr 2024 10:18:53 -0400 Subject: crypto: ecdsa - Rename keylen to bufsize where necessary In cases where 'keylen' was referring to the size of the buffer used by a curve's digits, it does not reflect the purpose of the variable anymore once NIST P521 is used. What it refers to then is the size of the buffer, which may be a few bytes larger than the size a coordinate of a key. Therefore, rename keylen to bufsize where appropriate. Tested-by: Lukas Wunner Reviewed-by: Jarkko Sakkinen Signed-off-by: Stefan Berger Signed-off-by: Herbert Xu --- crypto/ecdsa.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/crypto/ecdsa.c b/crypto/ecdsa.c index 75d3eea8..c7923f30 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); + ssize_t diff = vlen - bufsize; const char *d = value; u8 rs[ECC_MAX_BYTES]; @@ -58,7 +58,7 @@ static int ecdsa_get_signature_rs(u64 *dest, size_t hdrlen, unsigned char tag, if (diff) return -EINVAL; } - if (-diff >= keylen) + if (-diff >= bufsize) return -EINVAL; if (diff) { @@ -138,7 +138,7 @@ static int ecdsa_verify(struct akcipher_request *req) { struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); struct ecc_ctx *ctx = akcipher_tfm_ctx(tfm); - size_t keylen = ctx->curve->g.ndigits * sizeof(u64); + size_t bufsize = ctx->curve->g.ndigits * sizeof(u64); struct ecdsa_signature_ctx sig_ctx = { .curve = ctx->curve, }; @@ -165,14 +165,14 @@ static int ecdsa_verify(struct akcipher_request *req) goto error; /* if the hash is shorter then we will add leading zeros to fit to ndigits */ - diff = keylen - req->dst_len; + diff = bufsize - req->dst_len; if (diff >= 0) { if (diff) memset(rawhash, 0, diff); memcpy(&rawhash[diff], buffer + req->src_len, req->dst_len); } else if (diff < 0) { /* given hash is longer, we take the left-most bytes */ - memcpy(&rawhash, buffer + req->src_len, keylen); + memcpy(&rawhash, buffer + req->src_len, bufsize); } ecc_swap_digits((u64 *)rawhash, hash, ctx->curve->g.ndigits); -- cgit v1.2.3