From: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> To: linux-kernel@vger.kernel.org, x86@kernel.org, linux-sgx@vger.kernel.org Cc: akpm@linux-foundation.org, dave.hansen@intel.com, sean.j.christopherson@intel.com, nhorman@redhat.com, npmccallum@redhat.com, serge.ayoun@intel.com, shay.katz-zamir@intel.com, haitao.huang@intel.com, andriy.shevchenko@linux.intel.com, tglx@linutronix.de, kai.svahn@intel.com, bp@alien8.de, josh@joshtriplett.org, luto@kernel.org, kai.huang@intel.com, rientjes@google.com, cedric.xing@intel.com, puiterwijk@redhat.com, Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Subject: [PATCH v24 10/24] x86/sgx: Add sgx_einit() for wrapping ENCLS[EINIT] Date: Sat, 30 Nov 2019 01:13:12 +0200 Message-ID: <20191129231326.18076-11-jarkko.sakkinen@linux.intel.com> (raw) In-Reply-To: <20191129231326.18076-1-jarkko.sakkinen@linux.intel.com> From: Sean Christopherson <sean.j.christopherson@intel.com> Enclaves are SGX hosted measured and signed software entities. ENCLS[EINIT] leaf function checks that the enclave has a legit signed measurement and transforms the enclave to the state ready for execution. The signed measurement is provided by the caller in the form of SIGSTRUCT data structure [1]. Wrap ENCLS[EINIT] into sgx_einit(). Set MSR_IA32_SGXLEPUBKEYHASH* MSRs to match the public key contained in the SIGSTRUCT [2]. This sets Linux to enforce a policy where the provided public key is as long as the signed measurement matches the enclave contents in memory. Add a per-cpu cache to avoid unnecessary reads and write to the MSRs as they are expensive operations. [1] Intel SDM: 37.1.3 ENCLAVE SIGNATURE STRUCTURE (SIGSTRUCT) [2] Intel SDM: 38.1.4 Intel SGX Launch Control Configuration Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Co-developed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> --- arch/x86/kernel/cpu/sgx/Makefile | 1 + arch/x86/kernel/cpu/sgx/encls.c | 57 ++++++++++++++++++++++++++++++++ arch/x86/kernel/cpu/sgx/encls.h | 3 ++ 3 files changed, 61 insertions(+) create mode 100644 arch/x86/kernel/cpu/sgx/encls.c diff --git a/arch/x86/kernel/cpu/sgx/Makefile b/arch/x86/kernel/cpu/sgx/Makefile index 2dec75916a5e..874492d9e3bd 100644 --- a/arch/x86/kernel/cpu/sgx/Makefile +++ b/arch/x86/kernel/cpu/sgx/Makefile @@ -1,3 +1,4 @@ obj-y += \ + encls.o \ main.o \ reclaim.o diff --git a/arch/x86/kernel/cpu/sgx/encls.c b/arch/x86/kernel/cpu/sgx/encls.c new file mode 100644 index 000000000000..44291062967a --- /dev/null +++ b/arch/x86/kernel/cpu/sgx/encls.c @@ -0,0 +1,57 @@ +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) +// Copyright(c) 2016-19 Intel Corporation. + +#include <asm/cpufeature.h> +#include <asm/traps.h> +#include "encls.h" +#include "sgx.h" + +/* A per-cpu cache for the last known values of IA32_SGXLEPUBKEYHASHx MSRs. */ +static DEFINE_PER_CPU(u64 [4], sgx_lepubkeyhash_cache); + +static void sgx_update_lepubkeyhash_msrs(u64 *lepubkeyhash, bool enforce) +{ + u64 *cache; + int i; + + cache = per_cpu(sgx_lepubkeyhash_cache, smp_processor_id()); + for (i = 0; i < 4; i++) { + if (enforce || (lepubkeyhash[i] != cache[i])) { + wrmsrl(MSR_IA32_SGXLEPUBKEYHASH0 + i, lepubkeyhash[i]); + cache[i] = lepubkeyhash[i]; + } + } +} + +/** + * sgx_einit - initialize an enclave + * @sigstruct: a pointer a SIGSTRUCT + * @token: a pointer an EINITTOKEN (optional) + * @secs: a pointer a SECS + * @lepubkeyhash: the desired value for IA32_SGXLEPUBKEYHASHx MSRs + * + * Execute ENCLS[EINIT], writing the IA32_SGXLEPUBKEYHASHx MSRs according + * to @lepubkeyhash (if possible and necessary). + * + * Return: + * 0 on success, + * -errno or SGX error on failure + */ +int sgx_einit(struct sgx_sigstruct *sigstruct, struct sgx_einittoken *token, + struct sgx_epc_page *secs, u64 *lepubkeyhash) +{ + int ret; + + if (!boot_cpu_has(X86_FEATURE_SGX_LC)) + return __einit(sigstruct, token, sgx_epc_addr(secs)); + + preempt_disable(); + sgx_update_lepubkeyhash_msrs(lepubkeyhash, false); + ret = __einit(sigstruct, token, sgx_epc_addr(secs)); + if (ret == SGX_INVALID_EINITTOKEN) { + sgx_update_lepubkeyhash_msrs(lepubkeyhash, true); + ret = __einit(sigstruct, token, sgx_epc_addr(secs)); + } + preempt_enable(); + return ret; +} diff --git a/arch/x86/kernel/cpu/sgx/encls.h b/arch/x86/kernel/cpu/sgx/encls.h index d6381e4f6eb2..af94bbfe4cf6 100644 --- a/arch/x86/kernel/cpu/sgx/encls.h +++ b/arch/x86/kernel/cpu/sgx/encls.h @@ -248,4 +248,7 @@ static inline int __ewb(struct sgx_pageinfo *pginfo, void *addr, return __encls_ret_3(EWB, pginfo, addr, va); } +int sgx_einit(struct sgx_sigstruct *sigstruct, struct sgx_einittoken *token, + struct sgx_epc_page *secs, u64 *lepubkeyhash); + #endif /* _X86_ENCLS_H */ -- 2.20.1
next prev parent reply index Thread overview: 51+ messages / expand[flat|nested] mbox.gz Atom feed top 2019-11-29 23:13 [PATCH v24 00/24] Intel SGX foundations Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 01/24] x86/sgx: Update MAINTAINERS Jarkko Sakkinen 2019-11-30 1:38 ` Neil Horman 2019-11-30 14:37 ` Dr. Greg 2019-12-02 9:24 ` Jethro Beekman 2019-12-06 21:23 ` Jarkko Sakkinen 2019-12-06 21:24 ` Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 02/24] x86/cpufeatures: x86/msr: Add Intel SGX hardware bits Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 03/24] x86/cpufeatures: x86/msr: Intel SGX Launch Control " Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 04/24] x86/mm: x86/sgx: Signal SIGSEGV with PF_SGX Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 05/24] x86/sgx: Add SGX microarchitectural data structures Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 06/24] x86/sgx: Add wrappers for ENCLS leaf functions Jarkko Sakkinen 2019-12-17 14:45 ` Borislav Petkov 2019-12-19 0:39 ` Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 07/24] x86/cpu/intel: Detect SGX supprt Jarkko Sakkinen 2019-12-17 15:17 ` Borislav Petkov 2019-12-19 0:42 ` Jarkko Sakkinen 2019-12-19 6:15 ` Borislav Petkov 2019-12-23 9:46 ` Borislav Petkov 2019-12-27 6:00 ` Jarkko Sakkinen 2020-01-14 18:36 ` Sean Christopherson 2019-11-29 23:13 ` [PATCH v24 08/24] x86/sgx: Enumerate and track EPC sections Jarkko Sakkinen 2019-12-18 9:18 ` Borislav Petkov 2019-12-18 15:19 ` Sean Christopherson 2019-12-18 16:18 ` Borislav Petkov 2019-12-19 0:53 ` Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 09/24] x86/sgx: Add functions to allocate and free EPC pages Jarkko Sakkinen 2019-11-29 23:13 ` Jarkko Sakkinen [this message] 2019-11-29 23:13 ` [PATCH v24 11/24] mm: Introduce vm_ops->may_mprotect() Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 12/24] x86/sgx: Linux Enclave Driver Jarkko Sakkinen 2019-12-02 15:48 ` Haitao Huang 2019-12-02 18:21 ` Sean Christopherson 2019-12-09 19:38 ` Jarkko Sakkinen 2019-12-09 19:08 ` Jarkko Sakkinen 2020-01-14 16:12 ` Haitao Huang 2020-01-23 12:31 ` Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 13/24] selftests/x86: Recurse into subdirectories Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 14/24] selftests/x86: Add a selftest for SGX Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 15/24] x86/sgx: Add provisioning Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 16/24] x86/sgx: Add a page reclaimer Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 17/24] x86/sgx: ptrace() support for the SGX driver Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 18/24] x86/vdso: Add support for exception fixup in vDSO functions Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 19/24] x86/fault: Add helper function to sanitize error code Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 20/24] x86/traps: Attempt to fixup exceptions in vDSO before signaling Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 21/24] x86/vdso: Add __vdso_sgx_enter_enclave() to wrap SGX enclave transitions Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 22/24] selftests/x86: Add vDSO selftest for SGX Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 23/24] docs: x86/sgx: Document microarchitecture Jarkko Sakkinen 2019-11-29 23:13 ` [PATCH v24 24/24] docs: x86/sgx: Document kernel internals Jarkko Sakkinen 2019-12-20 13:26 ` [PATCH v24 00/24] Intel SGX foundations Nathaniel McCallum 2020-02-24 6:34 ` 三仟(惠春阳) 2020-02-25 10:15 ` Jarkko Sakkinen
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20191129231326.18076-11-jarkko.sakkinen@linux.intel.com \ --to=jarkko.sakkinen@linux.intel.com \ --cc=akpm@linux-foundation.org \ --cc=andriy.shevchenko@linux.intel.com \ --cc=bp@alien8.de \ --cc=cedric.xing@intel.com \ --cc=dave.hansen@intel.com \ --cc=haitao.huang@intel.com \ --cc=josh@joshtriplett.org \ --cc=kai.huang@intel.com \ --cc=kai.svahn@intel.com \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-sgx@vger.kernel.org \ --cc=luto@kernel.org \ --cc=nhorman@redhat.com \ --cc=npmccallum@redhat.com \ --cc=puiterwijk@redhat.com \ --cc=rientjes@google.com \ --cc=sean.j.christopherson@intel.com \ --cc=serge.ayoun@intel.com \ --cc=shay.katz-zamir@intel.com \ --cc=tglx@linutronix.de \ --cc=x86@kernel.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: link
Linux-Sgx Archive on lore.kernel.org Archives are clonable: git clone --mirror https://lore.kernel.org/linux-sgx/0 linux-sgx/git/0.git # If you have public-inbox 1.1+ installed, you may # initialize and index your mirror using the following commands: public-inbox-init -V2 linux-sgx linux-sgx/ https://lore.kernel.org/linux-sgx \ linux-sgx@vger.kernel.org public-inbox-index linux-sgx Example config snippet for mirrors Newsgroup available over NNTP: nntp://nntp.lore.kernel.org/org.kernel.vger.linux-sgx AGPL code for this site: git clone https://public-inbox.org/public-inbox.git