>From 92128f12a18372eefe01f8ee8c795305657715c7 Mon Sep 17 00:00:00 2001 Message-ID: <92128f12a18372eefe01f8ee8c795305657715c7.1789017384.git.gniibe@fsij.org> From: NIIBE Yutaka Date: Thu, 10 Sep 2026 14:14:24 +0900 Subject: [PATCH] cipher:keccak: Fix padding in cSHAKE. To: gcrypt-devel@gnupg.org MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="------------2.47.3" This is a multi-part message in MIME format. --------------2.47.3 Content-Type: text/plain; charset=UTF-8; format=fixed Content-Transfer-Encoding: 8bit * cipher/keccak.c (cshake_input_s): Fix PADLEN calculation. -- Reported-by: Jonathan Plata Signed-off-by: NIIBE Yutaka --- cipher/keccak.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --------------2.47.3 Content-Type: text/x-patch; name="0001-cipher-keccak-Fix-padding-in-cSHAKE.patch" Content-Transfer-Encoding: 8bit Content-Disposition: attachment; filename="0001-cipher-keccak-Fix-padding-in-cSHAKE.patch" diff --git a/cipher/keccak.c b/cipher/keccak.c index a0ba1fbb..5687e876 100644 --- a/cipher/keccak.c +++ b/cipher/keccak.c @@ -1694,7 +1694,8 @@ cshake_input_s (KECCAK_CONTEXT *ctx, const void *s, unsigned int s_len, keccak_write (ctx, s, s_len); len_written += buf[0] + 1 + s_len; - padlen = ctx->blocksize - (len_written % ctx->blocksize); + padlen = ctx->blocksize - 1 + - (len_written + ctx->blocksize - 1) % ctx->blocksize; memset (buf, 0, padlen); keccak_write (ctx, buf, padlen); } --------------2.47.3--