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 67B5AC25B78 for ; Tue, 4 Jun 2024 22:41:08 +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:From:Subject:Cc: To: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=XqhziOKg0qwQR9xxvoS+Uk0ft9/x4FOuer32xTMVqtE=; b=H/Vvh1I5h1HV+S G3L2N4uJAJYn5F0T8VUh/VMVupHL1C5nkFvhXnwgp9GoKFPgJuVPz3Db4L1dRIewevDbFEejoVPMS CmUW5vm/d3afAQVYyjRC7FrNvkgqEbFp5xcxp04nf7A6YDk1afAIJCEgkjkQLDpNBvCN70wxNapEH 73THxIbjpb612Qp4ecndMq7I69Oru6Nnx5sP80s253WEqxmWv8q9hfV2fzNWStQJlMb/PPZxnaP2r HO8zdXVXjWX7DL8DiMR0kj6XCbfsi1XPbmlizNkKyytshKA6gbu+kDj5+HoBx+SbBL6d3S0VGDCuV rzHsDq3JVYo+pgk1r5SA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sEcq3-0000000455Z-3dbw; Tue, 04 Jun 2024 22:41:07 +0000 Received: from sin.source.kernel.org ([2604:1380:40e1:4800::1]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sEcq0-0000000454U-3Ooh for kexec@lists.infradead.org; Tue, 04 Jun 2024 22:41:06 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id 3E6B3CE0E93; Tue, 4 Jun 2024 22:41:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B6950C2BBFC; Tue, 4 Jun 2024 22:40:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1717540861; bh=vw7d1yN78M9RgQ9Uv/CxeAyqib+2y0nfRQmhm1r8tqg=; h=Date:To:Cc:Subject:From:References:In-Reply-To:From; b=klTHSVF5uRzpHx0R6uJcsWmiMp9IKQD/4SkJAJDw/ofx6Cd2DzcvyynuoVLq3zTwL nfkpqjpJPPEQ36BKsH62/kUx8PuufC4egjJ6oTuUaReS88puer4ItAu4vFWTGeJ47+ 8iQ73F6rxAryaoNS09/a/Y6018ZToX+8aeEDfOyZETxvvk1UTkY/BfCmfdlKgRV5Ed tKXASYMpf4brgs+87MU8cCg9h1eRIBtzJimDZdnwgs+rxuN5EBvkXIsNjsa7cz9EpD Gtlk4JVMt1bG60GPRpOkIbuA3bxpweRhRmUY9otDYQFyRe5ACGqTeSSqlqGakkI67v KyEXa4igXHQaw== Mime-Version: 1.0 Date: Wed, 05 Jun 2024 01:40:54 +0300 Message-Id: To: , , , , , , , , Cc: , , , , , , , , , , , , , , , , , , , , , Subject: Re: [PATCH v9 06/19] x86: Add early SHA-1 support for Secure Launch early measurements From: "Jarkko Sakkinen" X-Mailer: aerc 0.17.0 References: <20240531010331.134441-1-ross.philipson@oracle.com> <20240531010331.134441-7-ross.philipson@oracle.com> <0ed3cdf6-2e4a-41f2-b2f6-363899405298@oracle.com> In-Reply-To: <0ed3cdf6-2e4a-41f2-b2f6-363899405298@oracle.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240604_154105_332189_CAF651EF X-CRM114-Status: GOOD ( 43.01 ) 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 Wed Jun 5, 2024 at 12:02 AM EEST, wrote: > On 6/4/24 11:52 AM, Jarkko Sakkinen wrote: > > 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? > > I am not 100% sure what you mean here, sorry. Could you clarify about > the prefix? Do you mean why did we choose early_*? There was precedent > for doing that like early_serial_console.c. Yep, that exactly. I'd just name as sha1.c. > > > > >> 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. > > We can do that. > > > > >> +} > >> + > >> +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; > > > > ? > > We could do it that way. I guess it would cut down in indenting. I defer > to Daniel Smith on this... Yep, that's why I requested this. > > > > >> + 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? > > > > ... and this. It only adds complexity with no gain. > > >> +} > >> + > >> +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? > > Yes it seems so. We will look at changing that. Yeah, AFAIK C99 should zero out anything remaining. > > > > >> + sha1_update(&sctx, data, len); > >> + sha1_final(&sctx, out); > >> +} > >> +EXPORT_SYMBOL(sha1); > >> + > >> MODULE_LICENSE("GPL"); > > > > BR, Jarkko > > Thanks > Ross BR, Jarkko _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec