diff options
Diffstat (limited to 'src/VBox/Runtime/r3/linux/tpm-linux.cpp')
| -rw-r--r-- | src/VBox/Runtime/r3/linux/tpm-linux.cpp | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/src/VBox/Runtime/r3/linux/tpm-linux.cpp b/src/VBox/Runtime/r3/linux/tpm-linux.cpp new file mode 100644 index 00000000..2fa46852 --- /dev/null +++ b/src/VBox/Runtime/r3/linux/tpm-linux.cpp @@ -0,0 +1,229 @@ +/* $Id: tpm-linux.cpp $ */ +/** @file + * IPRT - Trusted Platform Module (TPM) access, Linux variant. + */ + +/* + * Copyright (C) 2021-2022 Oracle and/or its affiliates. + * + * This file is part of VirtualBox base platform packages, as + * available from https://www.virtualbox.org. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, in version 3 of the + * License. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <https://www.gnu.org/licenses>. + * + * The contents of this file may alternatively be used under the terms + * of the Common Development and Distribution License Version 1.0 + * (CDDL), a copy of it is provided in the "COPYING.CDDL" file included + * in the VirtualBox distribution, in which case the provisions of the + * CDDL are applicable instead of those of the GPL. + * + * You may elect to license modified versions of this file under the + * terms and conditions of either the GPL or the CDDL or both. + * + * SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0 + */ + + +/********************************************************************************************************************************* +* Header Files * +*********************************************************************************************************************************/ +#define LOG_GROUP RTLOGGROUP_DEFAULT +#include <iprt/tpm.h> + +#include <iprt/assertcompile.h> +#include <iprt/asm.h> +#include <iprt/err.h> +#include <iprt/file.h> +#include <iprt/log.h> +#include <iprt/mem.h> +#include <iprt/string.h> +#include <iprt/linux/sysfs.h> + + +/********************************************************************************************************************************* +* Defined Constants And Macros * +*********************************************************************************************************************************/ + + +/********************************************************************************************************************************* +* Structures and Typedefs * +*********************************************************************************************************************************/ + +/** + * Internal TPM instance data. + */ +typedef struct RTTPMINT +{ + /** Handle to the /dev/tpmX device. */ + RTFILE hTpmDev; + /** Handle to the sysfs cancel interface. */ + RTFILE hTpmCancel; + /** The deduced TPM version. */ + RTTPMVERSION enmTpmVers; + /** Flag whether a request is currently being executed. */ + volatile bool fReqExec; +} RTTPMINT; +/** Pointer to the internal TPM instance data. */ +typedef RTTPMINT *PRTTPMINT; + + +/********************************************************************************************************************************* +* Internal Functions * +*********************************************************************************************************************************/ + +RTDECL(int) RTTpmOpen(PRTTPM phTpm, uint32_t idTpm) +{ + AssertPtrReturn(phTpm, VERR_INVALID_POINTER); + if (idTpm == RTTPM_ID_DEFAULT) + idTpm = 0; + + int rc = VINF_SUCCESS; + PRTTPMINT pThis = (PRTTPMINT)RTMemAllocZ(sizeof(*pThis)); + if (pThis) + { + pThis->hTpmDev = NIL_RTFILE; + pThis->hTpmCancel = NIL_RTFILE; + pThis->enmTpmVers = RTTPMVERSION_UNKNOWN; + pThis->fReqExec = false; + + rc = RTFileOpenF(&pThis->hTpmDev, RTFILE_O_OPEN | RTFILE_O_READWRITE | RTFILE_O_DENY_NONE, + "/dev/tpm%u", idTpm); + if (RT_SUCCESS(rc)) + { + /* Open the sysfs path to cancel a request, either /sys/class/tpm/tpmX/device/cancel or /sys/class/misc/tpmX/device/cancel. */ + rc = RTFileOpenF(&pThis->hTpmCancel, RTFILE_O_OPEN | RTFILE_O_WRITE | RTFILE_O_DENY_NONE, + "/sys/class/tpm/tpm%u/device/cancel", idTpm); + if (rc == VERR_FILE_NOT_FOUND) + rc = RTFileOpenF(&pThis->hTpmCancel, RTFILE_O_OPEN | RTFILE_O_WRITE | RTFILE_O_DENY_NONE, + "/sys/class/misc/tpm%u/device/cancel", idTpm); + if ( RT_SUCCESS(rc) + || rc == VERR_FILE_NOT_FOUND) + { + /* Try to figure out the TPM version. */ + int64_t iVersion = 0; + rc = RTLinuxSysFsReadIntFile(10 /*uBase*/, &iVersion, "/sys/class/tpm/tpm%u/tpm_version_major", idTpm); + if (rc == VERR_FILE_NOT_FOUND) + rc = RTLinuxSysFsReadIntFile(10 /*uBase*/, &iVersion, "/sys/class/misc/tpm%u/tpm_version_major", idTpm); + if (RT_SUCCESS(rc)) + { + if (iVersion == 1) + pThis->enmTpmVers = RTTPMVERSION_1_2; + else if (iVersion == 2) + pThis->enmTpmVers = RTTPMVERSION_2_0; + } + + *phTpm = pThis; + return VINF_SUCCESS; + } + + RTFileClose(pThis->hTpmDev); + pThis->hTpmDev = NIL_RTFILE; + } + + RTMemFree(pThis); + } + else + rc = VERR_NO_MEMORY; + return rc; +} + + +RTDECL(int) RTTpmClose(RTTPM hTpm) +{ + PRTTPMINT pThis = hTpm; + + AssertPtrReturn(pThis, VERR_INVALID_HANDLE); + + RTFileClose(pThis->hTpmDev); + if (pThis->hTpmCancel != NIL_RTFILE) + RTFileClose(pThis->hTpmCancel); + + pThis->hTpmDev = NIL_RTFILE; + pThis->hTpmCancel = NIL_RTFILE; + RTMemFree(pThis); + return VINF_SUCCESS; +} + + +RTDECL(RTTPMVERSION) RTTpmGetVersion(RTTPM hTpm) +{ + PRTTPMINT pThis = hTpm; + + AssertPtrReturn(pThis, RTTPMVERSION_INVALID); + return pThis->enmTpmVers; +} + + +RTDECL(uint32_t) RTTpmGetLocalityMax(RTTPM hTpm) +{ + RT_NOREF(hTpm); + return 0; /* On Linux only TPM locality 0 is supported. */ +} + + +RTDECL(int) RTTpmReqCancel(RTTPM hTpm) +{ + PRTTPMINT pThis = hTpm; + + AssertPtrReturn(pThis, VERR_INVALID_HANDLE); + if (pThis->hTpmCancel == NIL_RTFILE) + return VERR_NOT_SUPPORTED; + + if (ASMAtomicReadBool(&pThis->fReqExec)) + { + uint8_t bCancel = '-'; + return RTFileWrite(pThis->hTpmCancel, &bCancel, sizeof(bCancel), NULL /*pcbWritten*/); + } + + return VINF_SUCCESS; +} + + +RTDECL(int) RTTpmReqExec(RTTPM hTpm, uint8_t bLoc, const void *pvReq, size_t cbReq, + void *pvResp, size_t cbRespMax, size_t *pcbResp) +{ + PRTTPMINT pThis = hTpm; + + AssertPtrReturn(pThis, VERR_INVALID_HANDLE); + AssertPtrReturn(pvReq, VERR_INVALID_POINTER); + AssertPtrReturn(pvResp, VERR_INVALID_POINTER); + AssertReturn(cbReq && cbRespMax, VERR_INVALID_PARAMETER); + AssertReturn(bLoc == 0, VERR_NOT_SUPPORTED); /** @todo There doesn't seem to be a way to use a different locality. */ + + /* The request has to be supplied by a single blocking write. */ + ASMAtomicXchgBool(&pThis->fReqExec, true); + int rc = RTFileWrite(pThis->hTpmDev, pvReq, cbReq, NULL /*pcbWritten*/); + if (RT_SUCCESS(rc)) + { + size_t cbResp = 0; + /* The response has to be retrieved in a single read as well. */ + rc = RTFileRead(pThis->hTpmDev, pvResp, cbRespMax, &cbResp); + ASMAtomicXchgBool(&pThis->fReqExec, false); + if (RT_SUCCESS(rc)) + { + /* Check whether the response is complete. */ + if ( cbResp >= sizeof(TPMRESPHDR) + && RTTpmRespGetSz((PCTPMRESPHDR)pvResp) == cbResp) + { + if (pcbResp) + *pcbResp = cbResp; + } + else + rc = VERR_BUFFER_OVERFLOW; + } + } + + return rc; +} + |