From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C0F8EC25B78 for ; Tue, 4 Jun 2024 18:52:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:References:To:From:Subject: Cc:Message-Id:Date:Mime-Version:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=e/lkRZyF9beHDNNOY+9AUuSyNpyW4hh9gT63BvpUgMg=; b=fC2YHZxw41FCsu SCFBL4wTinnwuyko9rbZDcYAIefHpR1VqvCqktb77HUuk9JkQF15vlUKt2m/OBCT1XF7uNVowhlex 0sn0qW7XpjVM3CIvjCrYVMNHZFItfDSvcDMJA76onWVJOaOJLS98YE8FyfGTk5/QDUBRo+yYCVyqa MowzyN8Egzcx6hOOGLXQNV1cVTGr2Tsw7DfFnT2kduIlRYUeWLn9JOj+aYu1wEkFqaLN7ZVve8/Em uACVOqGV2nGxJOz3ZP/MkB6K5vCLrbDzQ8ZJ2KkrSjFqjQ4Gf5/G6TkyJM4fDWSTqE1dtADHpx8HI CsTaQSddeqgnTu306BVg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sEZGq-00000003V2J-327A; Tue, 04 Jun 2024 18:52:32 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sEZGn-00000003V0O-2tJz for kexec@lists.infradead.org; Tue, 04 Jun 2024 18:52:31 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 0E96C6143A; Tue, 4 Jun 2024 18:52:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D612CC2BBFC; Tue, 4 Jun 2024 18:52:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1717527148; bh=WWH33RP1o5Qg05eJ8r9JvDT1Wv6XYAs8lOgl4ISqoq8=; h=Date:Cc:Subject:From:To:References:In-Reply-To:From; b=Md9bXG+PizBDYmRG3tn1IrdW/6JZBrceK1yZ8SUCpiSSD2j81VkmKoPTgTQ25tz+t 8ynwvq8HMFa6OhUsZ5oHLquws90ATj8DerOaO9XHRwyBgQ3XlH1MBsHo8nLps1G7v7 Og2atXobM6Jo6e6tkgZErgnFD/1tVaDkpHzp+kpmU67Ne7icB6yoSbxz1TlSeC8o4k 2Uyu8Eu460PtoI/YSUV++IBS9gmza22773TYhbWLfuZFDnMhiIhWt/TrkxKbRq+QoA /I8Rt6aJYXwmLudczPLW4emg3FGZOUMZH7FMcpnWCHmggtGM7Czq8xbNIaPckcgN4W UnilDqYAur8ZQ== Mime-Version: 1.0 Date: Tue, 04 Jun 2024 21:52:21 +0300 Message-Id: Cc: , , , , , , , , , , , , , , , , , , , , , Subject: Re: [PATCH v9 06/19] x86: Add early SHA-1 support for Secure Launch early measurements From: "Jarkko Sakkinen" To: "Ross Philipson" , , , , , , , , X-Mailer: aerc 0.17.0 References: <20240531010331.134441-1-ross.philipson@oracle.com> <20240531010331.134441-7-ross.philipson@oracle.com> In-Reply-To: <20240531010331.134441-7-ross.philipson@oracle.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240604_115229_845339_45A5CC19 X-CRM114-Status: GOOD ( 31.40 ) X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org On Fri May 31, 2024 at 4:03 AM EEST, Ross Philipson wrote: > From: "Daniel P. Smith" > > For better or worse, Secure Launch needs SHA-1 and SHA-256. The > choice of hashes used lie with the platform firmware, not with > software, and is often outside of the users control. > > Even if we'd prefer to use SHA-256-only, if firmware elected to start us > with the SHA-1 and SHA-256 backs active, we still need SHA-1 to parse > the TPM event log thus far, and deliberately cap the SHA-1 PCRs in order > to safely use SHA-256 for everything else. > > The SHA-1 code here has its origins in the code from the main kernel: > > commit c4d5b9ffa31f ("crypto: sha1 - implement base layer for SHA-1") > > A modified version of this code was introduced to the lib/crypto/sha1.c > to bring it in line with the SHA-256 code and allow it to be pulled into the > setup kernel in the same manner as SHA-256 is. > > Signed-off-by: Daniel P. Smith > Signed-off-by: Ross Philipson > --- > arch/x86/boot/compressed/Makefile | 2 + > arch/x86/boot/compressed/early_sha1.c | 12 ++++ > include/crypto/sha1.h | 1 + > lib/crypto/sha1.c | 81 +++++++++++++++++++++++++++ > 4 files changed, 96 insertions(+) > create mode 100644 arch/x86/boot/compressed/early_sha1.c > > diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile > index e9522c6893be..3307ebef4e1b 100644 > --- a/arch/x86/boot/compressed/Makefile > +++ b/arch/x86/boot/compressed/Makefile > @@ -118,6 +118,8 @@ vmlinux-objs-$(CONFIG_EFI) += $(obj)/efi.o > vmlinux-objs-$(CONFIG_EFI_MIXED) += $(obj)/efi_mixed.o > vmlinux-objs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a > > +vmlinux-objs-$(CONFIG_SECURE_LAUNCH) += $(obj)/early_sha1.o > + > $(obj)/vmlinux: $(vmlinux-objs-y) FORCE > $(call if_changed,ld) > > diff --git a/arch/x86/boot/compressed/early_sha1.c b/arch/x86/boot/compressed/early_sha1.c > new file mode 100644 > index 000000000000..8a9b904a73ab > --- /dev/null > +++ b/arch/x86/boot/compressed/early_sha1.c > @@ -0,0 +1,12 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (c) 2024 Apertus Solutions, LLC. > + */ > + > +#include > +#include > +#include > +#include > +#include > + > +#include "../../../../lib/crypto/sha1.c" } Yep, make sense. Thinking only that should this be just sha1.c. Comparing this to mainly drivers/firmware/efi/tpm.c, which is not early_tpm.c where the early actually probably would make more sense than here. Here sha1 primitive is just needed. This is definitely a nitpick but why carry a prefix that is not that useful, right? > diff --git a/include/crypto/sha1.h b/include/crypto/sha1.h > index 044ecea60ac8..d715dd5332e1 100644 > --- a/include/crypto/sha1.h > +++ b/include/crypto/sha1.h > @@ -42,5 +42,6 @@ extern int crypto_sha1_finup(struct shash_desc *desc, const u8 *data, > #define SHA1_WORKSPACE_WORDS 16 > void sha1_init(__u32 *buf); > void sha1_transform(__u32 *digest, const char *data, __u32 *W); > +void sha1(const u8 *data, unsigned int len, u8 *out); > > #endif /* _CRYPTO_SHA1_H */ > diff --git a/lib/crypto/sha1.c b/lib/crypto/sha1.c > index 1aebe7be9401..10152125b338 100644 > --- a/lib/crypto/sha1.c > +++ b/lib/crypto/sha1.c > @@ -137,4 +137,85 @@ void sha1_init(__u32 *buf) > } > EXPORT_SYMBOL(sha1_init); > > +static void __sha1_transform(u32 *digest, const char *data) > +{ > + u32 ws[SHA1_WORKSPACE_WORDS]; > + > + sha1_transform(digest, data, ws); > + > + memzero_explicit(ws, sizeof(ws)); For the sake of future reference I'd carry always some inline comment with any memzero_explicit() call site. > +} > + > +static void sha1_update(struct sha1_state *sctx, const u8 *data, unsigned int len) > +{ > + unsigned int partial = sctx->count % SHA1_BLOCK_SIZE; > + > + sctx->count += len; > + > + if (likely((partial + len) >= SHA1_BLOCK_SIZE)) { if (unlikely((partial + len) < SHA1_BLOCK_SIZE)) goto out; ? > + int blocks; > + > + if (partial) { > + int p = SHA1_BLOCK_SIZE - partial; > + > + memcpy(sctx->buffer + partial, data, p); > + data += p; > + len -= p; > + > + __sha1_transform(sctx->state, sctx->buffer); > + } > + > + blocks = len / SHA1_BLOCK_SIZE; > + len %= SHA1_BLOCK_SIZE; > + > + if (blocks) { > + while (blocks--) { > + __sha1_transform(sctx->state, data); > + data += SHA1_BLOCK_SIZE; > + } > + } > + partial = 0; > + } > + out: > + if (len) > + memcpy(sctx->buffer + partial, data, len); Why not just memcpy() unconditionally? > +} > + > +static void sha1_final(struct sha1_state *sctx, u8 *out) > +{ > + const int bit_offset = SHA1_BLOCK_SIZE - sizeof(__be64); > + unsigned int partial = sctx->count % SHA1_BLOCK_SIZE; > + __be64 *bits = (__be64 *)(sctx->buffer + bit_offset); > + __be32 *digest = (__be32 *)out; > + int i; > + > + sctx->buffer[partial++] = 0x80; > + if (partial > bit_offset) { > + memset(sctx->buffer + partial, 0x0, SHA1_BLOCK_SIZE - partial); > + partial = 0; > + > + __sha1_transform(sctx->state, sctx->buffer); > + } > + > + memset(sctx->buffer + partial, 0x0, bit_offset - partial); > + *bits = cpu_to_be64(sctx->count << 3); > + __sha1_transform(sctx->state, sctx->buffer); > + > + for (i = 0; i < SHA1_DIGEST_SIZE / sizeof(__be32); i++) > + put_unaligned_be32(sctx->state[i], digest++); > + > + *sctx = (struct sha1_state){}; > +} > + > +void sha1(const u8 *data, unsigned int len, u8 *out) > +{ > + struct sha1_state sctx = {0}; > + > + sha1_init(sctx.state); > + sctx.count = 0; Hmm... so shouldn't C99 take care of this given the initialization above? I'm not 100% sure here. I.e. given "= {0}", shouldn't this already be zero? > + sha1_update(&sctx, data, len); > + sha1_final(&sctx, out); > +} > +EXPORT_SYMBOL(sha1); > + > MODULE_LICENSE("GPL"); BR, Jarkko _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec