From patchwork Thu Nov 25 18:02:40 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michal Suchanek X-Patchwork-Id: 1559852 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: bilbo.ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=suse.de header.i=@suse.de header.a=rsa-sha256 header.s=susede2_rsa header.b=RKhgYgum; dkim=fail reason="signature verification failed" header.d=suse.de header.i=@suse.de header.a=ed25519-sha256 header.s=susede2_ed25519 header.b=uHz1kBfG; dkim-atps=neutral Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lists.ozlabs.org (client-ip=112.213.38.117; helo=lists.ozlabs.org; envelope-from=linuxppc-dev-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org; receiver=) Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by bilbo.ozlabs.org (Postfix) with ESMTPS id 4J0QnJ6wqhz9sRN for ; Fri, 26 Nov 2021 05:07:00 +1100 (AEDT) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4J0QnJ5ks9z3dxQ for ; Fri, 26 Nov 2021 05:07:00 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=suse.de header.i=@suse.de header.a=rsa-sha256 header.s=susede2_rsa header.b=RKhgYgum; dkim=fail reason="signature verification failed" header.d=suse.de header.i=@suse.de header.a=ed25519-sha256 header.s=susede2_ed25519 header.b=uHz1kBfG; dkim-atps=neutral X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=suse.de (client-ip=195.135.220.29; helo=smtp-out2.suse.de; envelope-from=msuchanek@suse.de; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=suse.de header.i=@suse.de header.a=rsa-sha256 header.s=susede2_rsa header.b=RKhgYgum; dkim=pass header.d=suse.de header.i=@suse.de header.a=ed25519-sha256 header.s=susede2_ed25519 header.b=uHz1kBfG; dkim-atps=neutral Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4J0QjN3DbQz2yPd for ; Fri, 26 Nov 2021 05:03:36 +1100 (AEDT) Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out2.suse.de (Postfix) with ESMTP id 42D491FD3C; Thu, 25 Nov 2021 18:03:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1637863413; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=l0S/rnnLVvNbU+CCOjj4LWqQa7IdIcdMPBDgplAns6U=; b=RKhgYgumwvJoAQSsGPnYDj+iUVI8D4UZ40tFmowliQAdb+89lTJC7fINQv+liE3oLpVdZq YWyf4GXI5PKsipvnNP50uqYRLdawaTMeuVaUdHSBeoIgikhELwOd+UyGUoyHE3JVXhoV4g Q6/6rzZKN12y3pGVkKq4HxT/rLs5MOM= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1637863413; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=l0S/rnnLVvNbU+CCOjj4LWqQa7IdIcdMPBDgplAns6U=; b=uHz1kBfG6gD9l+Me+xoTs0h/Oult6KQZ0g+sXgatAGa3xXpm5190+t5RLzh1Pqhu85Rr3n 6hfHDRALXl8O44BQ== Received: from kitsune.suse.cz (kitsune.suse.cz [10.100.12.127]) by relay2.suse.de (Postfix) with ESMTP id EC8B9A3B87; Thu, 25 Nov 2021 18:03:32 +0000 (UTC) From: Michal Suchanek To: keyrings@vger.kernel.org Subject: [PATCH v2 2/6] powerpc/kexec_file: Add KEXEC_SIG support. Date: Thu, 25 Nov 2021 19:02:40 +0100 Message-Id: <8b30a3c6a4e845eb77f276298424811897efdebf.1637862358.git.msuchanek@suse.de> X-Mailer: git-send-email 2.31.1 In-Reply-To: References: MIME-Version: 1.0 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Nayna , Mimi Zohar , David Howells , Paul Mackerras , Alexander Gordeev , Rob Herring , Herbert Xu , Baoquan He , Christian Borntraeger , James Morris , Lakshmi Ramasubramanian , Michal Suchanek , "Serge E. Hallyn" , Vasily Gorbik , linux-s390@vger.kernel.org, Heiko Carstens , linux-crypto@vger.kernel.org, Dmitry Kasatkin , Hari Bathini , Daniel Axtens , Christian Borntraeger , Philipp Rudo , Frank van der Linden , kexec@lists.infradead.org, linux-kernel@vger.kernel.org, Luis Chamberlain , Sven Schnelle , linux-security-module@vger.kernel.org, Jessica Yu , linux-integrity@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, "David S. Miller" , Thiago Jung Bauermann , buendgen@de.ibm.com Errors-To: linuxppc-dev-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Copy the code from s390x Signed-off-by: Michal Suchanek --- arch/powerpc/Kconfig | 11 +++++++++++ arch/powerpc/kexec/elf_64.c | 36 ++++++++++++++++++++++++++++++++++++ 2 files changed, 47 insertions(+) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index ac0c515552fd..ecc1227a77f1 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -561,6 +561,17 @@ config KEXEC_FILE config ARCH_HAS_KEXEC_PURGATORY def_bool KEXEC_FILE +config KEXEC_SIG + bool "Verify kernel signature during kexec_file_load() syscall" + depends on KEXEC_FILE && MODULE_SIG_FORMAT + help + This option makes kernel signature verification mandatory for + the kexec_file_load() syscall. + + In addition to that option, you need to enable signature + verification for the corresponding kernel image type being + loaded in order for this to work. + config PPC64_BUILD_ELF_V2_ABI bool diff --git a/arch/powerpc/kexec/elf_64.c b/arch/powerpc/kexec/elf_64.c index eeb258002d1e..25dc1071feec 100644 --- a/arch/powerpc/kexec/elf_64.c +++ b/arch/powerpc/kexec/elf_64.c @@ -23,6 +23,7 @@ #include #include #include +#include static void *elf64_load(struct kimage *image, char *kernel_buf, unsigned long kernel_len, char *initrd, @@ -151,7 +152,42 @@ static void *elf64_load(struct kimage *image, char *kernel_buf, return ret ? ERR_PTR(ret) : NULL; } +#ifdef CONFIG_KEXEC_SIG +int elf64_verify_sig(const char *kernel, unsigned long kernel_len) +{ + const unsigned long marker_len = sizeof(MODULE_SIG_STRING) - 1; + struct module_signature *ms; + unsigned long sig_len; + int ret; + + if (marker_len > kernel_len) + return -EKEYREJECTED; + + if (memcmp(kernel + kernel_len - marker_len, MODULE_SIG_STRING, + marker_len)) + return -EKEYREJECTED; + kernel_len -= marker_len; + + ms = (void *)kernel + kernel_len - sizeof(*ms); + ret = mod_check_sig(ms, kernel_len, "kexec"); + if (ret) + return ret; + + sig_len = be32_to_cpu(ms->sig_len); + kernel_len -= sizeof(*ms) + sig_len; + + return verify_pkcs7_signature(kernel, kernel_len, + kernel + kernel_len, sig_len, + VERIFY_USE_PLATFORM_KEYRING, + VERIFYING_MODULE_SIGNATURE, + NULL, NULL); +} +#endif /* CONFIG_KEXEC_SIG */ + const struct kexec_file_ops kexec_elf64_ops = { .probe = kexec_elf_probe, .load = elf64_load, +#ifdef CONFIG_KEXEC_SIG + .verify_sig = elf64_verify_sig, +#endif };