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 X-Spam-Level: X-Spam-Status: No, score=-16.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3FBD8C04AB4 for ; Fri, 17 May 2019 21:39:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 04A9D206A3 for ; Fri, 17 May 2019 21:39:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="EQVVmRZX" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729638AbfEQVjg (ORCPT ); Fri, 17 May 2019 17:39:36 -0400 Received: from mail-qt1-f201.google.com ([209.85.160.201]:50637 "EHLO mail-qt1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729624AbfEQVje (ORCPT ); Fri, 17 May 2019 17:39:34 -0400 Received: by mail-qt1-f201.google.com with SMTP id i5so7727117qtd.17 for ; Fri, 17 May 2019 14:39:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=/ITrQNIi0NTjerZ5MiR7r+4SVrslKsoTGUVP7IEv6kU=; b=EQVVmRZXphR6AKeVQ4JSoeX5ztR2+S1HUTR1XM5/6QvgP1eBiAXVWL3Ro0ebl1UuQU U7IMllkNfVgGtOvqZhrKhuiM/Pmm/bQ0WaDVwgWs4bIR9+VOFHmCUxcyJVwGGaRJ8HPC LEfCOxuK2SlCVJ3xuvJVjzewGoWYg6RJlVtdlfeVYegnHznxZWo7LOsiEOmPaTY5Kyg2 r2bCvjNjnIlbxAXrZrlySsa+IRF2Y3qRZkqjjuUS1gPsphxbbWbwUNh2TkkaILJBEkCf L99WWMZx63g9f3xLjPfZqME23QkJo6o/Sc3EIg8HsbGNBiseDxLcQyc5zjang4tRyEur XUMw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=/ITrQNIi0NTjerZ5MiR7r+4SVrslKsoTGUVP7IEv6kU=; b=RgDWkH8vQm11zN3x5H7Rtdc7DT273fEzeaRfOprR+WL1ynonmX6S/whQE/lP0T9bcN hKq6ASvsnzIzV+3Bsqsh96ng5v8ViGxVS9AIkAIPKxJcdYDPRJkGFot81TyozBtIr+p7 YfS0q/QnrxAnjrnoMRVIdXslARYvD5GVItXCvANyzkBRgFSvSZ9feCelBvfP15s8SsQj 5S1/MARYeiQlFpHoJ37txXFQLbh7lT7ndLaXLcBDVULDdSY1BgqDCHTLyhz+J7rsaAjY KUyKUG56QQn8pp7+F9tFOo9ErFPUAVT3m4fbN2Yd++QiGRQjgYN6hA0zUCIxwdaR7nFH V+ZQ== X-Gm-Message-State: APjAAAXauqrKgfIWB7lKa5yq61nQXLYu2lvbh0TgegUr6fhqFau7f9hu HXlAnRfbDj3iQwaU8bMOPOnqec+D+IcP4Id20JeU6A== X-Google-Smtp-Source: APXvYqxuE90XrZHB/VO7+Xrb4zeWDdpZr9ZkE2jFp92Gxnl0nXadyAYNdgO+zMIR06dwvERZz59AduFXGXMHenfcK2FqyA== X-Received: by 2002:a37:34b:: with SMTP id 72mr46524708qkd.42.1558129172544; Fri, 17 May 2019 14:39:32 -0700 (PDT) Date: Fri, 17 May 2019 14:39:18 -0700 In-Reply-To: <20190517213918.26045-1-matthewgarrett@google.com> Message-Id: <20190517213918.26045-5-matthewgarrett@google.com> Mime-Version: 1.0 References: <20190517213918.26045-1-matthewgarrett@google.com> X-Mailer: git-send-email 2.21.0.1020.gf2820cf01a-goog Subject: [PATCH V6 4/4] efi: Attempt to get the TCG2 event log in the boot stub From: Matthew Garrett To: linux-integrity@vger.kernel.org Cc: peterhuewe@gmx.de, jarkko.sakkinen@linux.intel.com, jgg@ziepe.ca, roberto.sassu@huawei.com, linux-efi@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, tweek@google.com, bsz@semihalf.com, Matthew Garrett Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Matthew Garrett Right now we only attempt to obtain the SHA1-only event log. The protocol also supports a crypto agile log format, which contains digests for all algorithms in use. Attempt to obtain this first, and fall back to obtaining the older format if the system doesn't support it. This is lightly complicated by the event sizes being variable (as we don't know in advance which algorithms are in use), and the interface giving us back a pointer to the start of the final entry rather than a pointer to the end of the log - as a result, we need to parse the final entry to figure out its length in order to know how much data to copy up to the OS. Signed-off-by: Matthew Garrett Tested-by: Jarkko Sakkinen Reviewed-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen --- drivers/firmware/efi/libstub/tpm.c | 57 ++++++++++++++++++++---------- 1 file changed, 39 insertions(+), 18 deletions(-) diff --git a/drivers/firmware/efi/libstub/tpm.c b/drivers/firmware/efi/libstub/tpm.c index 5bd04f75d8d6..b3f30448e454 100644 --- a/drivers/firmware/efi/libstub/tpm.c +++ b/drivers/firmware/efi/libstub/tpm.c @@ -8,8 +8,13 @@ * Thiebaud Weksteen */ #include -#include #include +/* + * KASAN redefines memcpy() in a way that isn't available in the EFI stub. + * We need to include asm/efi.h before linux/tpm_eventlog.h in order to avoid + * the wrong memcpy() being referenced. + */ +#include #include "efistub.h" @@ -57,7 +62,7 @@ void efi_enable_reset_attack_mitigation(efi_system_table_t *sys_table_arg) #endif -static void efi_retrieve_tpm2_eventlog_1_2(efi_system_table_t *sys_table_arg) +void efi_retrieve_tpm2_eventlog(efi_system_table_t *sys_table_arg) { efi_guid_t tcg2_guid = EFI_TCG2_PROTOCOL_GUID; efi_guid_t linux_eventlog_guid = LINUX_EFI_TPM_EVENT_LOG_GUID; @@ -67,6 +72,7 @@ static void efi_retrieve_tpm2_eventlog_1_2(efi_system_table_t *sys_table_arg) unsigned long first_entry_addr, last_entry_addr; size_t log_size, last_entry_size; efi_bool_t truncated; + int version = EFI_TCG2_EVENT_LOG_FORMAT_TCG_2; void *tcg2_protocol = NULL; status = efi_call_early(locate_protocol, &tcg2_guid, NULL, @@ -74,14 +80,20 @@ static void efi_retrieve_tpm2_eventlog_1_2(efi_system_table_t *sys_table_arg) if (status != EFI_SUCCESS) return; - status = efi_call_proto(efi_tcg2_protocol, get_event_log, tcg2_protocol, - EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2, - &log_location, &log_last_entry, &truncated); - if (status != EFI_SUCCESS) - return; + status = efi_call_proto(efi_tcg2_protocol, get_event_log, + tcg2_protocol, version, &log_location, + &log_last_entry, &truncated); + + if (status != EFI_SUCCESS || !log_location) { + version = EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2; + status = efi_call_proto(efi_tcg2_protocol, get_event_log, + tcg2_protocol, version, &log_location, + &log_last_entry, &truncated); + if (status != EFI_SUCCESS || !log_location) + return; + + } - if (!log_location) - return; first_entry_addr = (unsigned long) log_location; /* @@ -96,8 +108,23 @@ static void efi_retrieve_tpm2_eventlog_1_2(efi_system_table_t *sys_table_arg) * We need to calculate its size to deduce the full size of * the logs. */ - last_entry_size = sizeof(struct tcpa_event) + - ((struct tcpa_event *) last_entry_addr)->event_size; + if (version == EFI_TCG2_EVENT_LOG_FORMAT_TCG_2) { + /* + * The TCG2 log format has variable length entries, + * and the information to decode the hash algorithms + * back into a size is contained in the first entry - + * pass a pointer to the final entry (to calculate its + * size) and the first entry (so we know how long each + * digest is) + */ + last_entry_size = + __calc_tpm2_event_size((void *)last_entry_addr, + (void *)(long)log_location, + false); + } else { + last_entry_size = sizeof(struct tcpa_event) + + ((struct tcpa_event *) last_entry_addr)->event_size; + } log_size = log_last_entry - log_location + last_entry_size; } @@ -114,7 +141,7 @@ static void efi_retrieve_tpm2_eventlog_1_2(efi_system_table_t *sys_table_arg) memset(log_tbl, 0, sizeof(*log_tbl) + log_size); log_tbl->size = log_size; - log_tbl->version = EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2; + log_tbl->version = version; memcpy(log_tbl->log, (void *) first_entry_addr, log_size); status = efi_call_early(install_configuration_table, @@ -126,9 +153,3 @@ static void efi_retrieve_tpm2_eventlog_1_2(efi_system_table_t *sys_table_arg) err_free: efi_call_early(free_pool, log_tbl); } - -void efi_retrieve_tpm2_eventlog(efi_system_table_t *sys_table_arg) -{ - /* Only try to retrieve the logs in 1.2 format. */ - efi_retrieve_tpm2_eventlog_1_2(sys_table_arg); -} -- 2.21.0.1020.gf2820cf01a-goog