/* $Id: krnlmod-linux.cpp 76553 2019-01-01 01:45:53Z vboxsync $ */ /** @file * IPRT - Kernel module, Linux. */ /* * Copyright (C) 2017-2019 Oracle Corporation * * This file is part of VirtualBox Open Source Edition (OSE), as * available from http://www.virtualbox.org. This file is free software; * you can redistribute it and/or modify it under the terms of the GNU * General Public License (GPL) as published by the Free Software * Foundation, in version 2 as it comes in the "COPYING" file of the * VirtualBox OSE distribution. VirtualBox OSE is distributed in the * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind. * * The contents of this file may alternatively be used under the terms * of the Common Development and Distribution License Version 1.0 * (CDDL) only, as it comes in the "COPYING.CDDL" file of the * VirtualBox OSE 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. */ /********************************************************************************************************************************* * Header Files * *********************************************************************************************************************************/ #define LOG_GROUP RTLOGGROUP_SYSTEM #include #include #include #include #include #include #include #include #include /** * Internal kernel information record state. */ typedef struct RTKRNLMODINFOINT { /** Reference counter. */ volatile uint32_t cRefs; /** Reference count for the kernel module. */ uint32_t cRefKrnlMod; /** Load address of the kernel module. */ RTR0UINTPTR uLoadAddr; /** Size of the kernel module. */ size_t cbKrnlMod; /** Size of the name in characters including the zero terminator. */ size_t cchName; /** Module name - variable in size. */ char achName[1]; } RTKRNLMODINFOINT; /** Pointer to the internal kernel module information record. */ typedef RTKRNLMODINFOINT *PRTKRNLMODINFOINT; /** Pointer to a const internal kernel module information record. */ typedef const RTKRNLMODINFOINT *PCRTKRNLMODINFOINT; /** * Destroy the given kernel module information record. * * @returns nothing. * @param pThis The record to destroy. */ static void rtKrnlModInfoDestroy(PRTKRNLMODINFOINT pThis) { RTMemFree(pThis); } static int rtKrnlModLinuxReadIntFileDef(unsigned uBase, int64_t *pi64, int64_t i64Def, const char *pszName, const char *pszPath) { int rc = RTLinuxSysFsReadIntFile(uBase, pi64, "module/%s/%s", pszName, pszPath); if (rc == VERR_FILE_NOT_FOUND) { *pi64 = i64Def; rc = VINF_SUCCESS; } return rc; } /** * Creates a new kernel module information record for the given module. * * @returns IPRT status code. * @param pszName The kernel module name. * @param phKrnlModInfo Where to store the handle to the kernel module information record * on success. */ static int rtKrnlModLinuxInfoCreate(const char *pszName, PRTKRNLMODINFO phKrnlModInfo) { int rc = VINF_SUCCESS; size_t cchName = strlen(pszName) + 1; PRTKRNLMODINFOINT pThis = (PRTKRNLMODINFOINT)RTMemAllocZ(RT_UOFFSETOF_DYN(RTKRNLMODINFOINT, achName[cchName])); if (RT_LIKELY(pThis)) { memcpy(&pThis->achName[0], pszName, cchName); pThis->cchName = cchName; pThis->cRefs = 1; int64_t iTmp = 0; rc = rtKrnlModLinuxReadIntFileDef(10, &iTmp, 0, pszName, "refcnt"); if (RT_SUCCESS(rc)) pThis->cRefKrnlMod = (uint32_t)iTmp; rc = rtKrnlModLinuxReadIntFileDef(10, &iTmp, 0, pszName, "coresize"); if (RT_SUCCESS(rc)) pThis->cbKrnlMod = iTmp; rc = rtKrnlModLinuxReadIntFileDef(16, &iTmp, 0, pszName, "sections/.text"); if (RT_SUCCESS(rc)) pThis->uLoadAddr = iTmp; if (RT_SUCCESS(rc)) *phKrnlModInfo = pThis; else RTMemFree(pThis); } else rc = VERR_NO_MEMORY; return rc; } RTDECL(int) RTKrnlModQueryLoaded(const char *pszName, bool *pfLoaded) { AssertPtrReturn(pszName, VERR_INVALID_POINTER); AssertPtrReturn(pfLoaded, VERR_INVALID_POINTER); int rc = RTLinuxSysFsExists("module/%s", pszName); if (rc == VINF_SUCCESS) *pfLoaded = true; else if (rc == VERR_FILE_NOT_FOUND) { *pfLoaded = false; rc = VINF_SUCCESS; } return rc; } RTDECL(int) RTKrnlModLoadedQueryInfo(const char *pszName, PRTKRNLMODINFO phKrnlModInfo) { AssertPtrReturn(pszName, VERR_INVALID_POINTER); AssertPtrReturn(phKrnlModInfo, VERR_INVALID_POINTER); int rc = RTLinuxSysFsExists("module/%s", pszName); if (rc == VINF_SUCCESS) rc = rtKrnlModLinuxInfoCreate(pszName, phKrnlModInfo); else if (rc == VERR_FILE_NOT_FOUND) rc = VERR_NOT_FOUND; return rc; } RTDECL(uint32_t) RTKrnlModLoadedGetCount(void) { uint32_t cKmodsLoaded = 0; RTDIR hDir = NULL; int rc = RTDirOpen(&hDir, "/sys/module"); if (RT_SUCCESS(rc)) { RTDIRENTRY DirEnt; rc = RTDirRead(hDir, &DirEnt, NULL); while (RT_SUCCESS(rc)) { if (!RTDirEntryIsStdDotLink(&DirEnt)) cKmodsLoaded++; rc = RTDirRead(hDir, &DirEnt, NULL); } RTDirClose(hDir); } return cKmodsLoaded; } RTDECL(int) RTKrnlModLoadedQueryInfoAll(PRTKRNLMODINFO pahKrnlModInfo, uint32_t cEntriesMax, uint32_t *pcEntries) { AssertReturn(VALID_PTR(pahKrnlModInfo) || cEntriesMax == 0, VERR_INVALID_PARAMETER); uint32_t cKmodsLoaded = RTKrnlModLoadedGetCount(); if (cEntriesMax < cKmodsLoaded) { if (*pcEntries) *pcEntries = cKmodsLoaded; return VERR_BUFFER_OVERFLOW; } RTDIR hDir = NULL; int rc = RTDirOpen(&hDir, "/sys/module"); if (RT_SUCCESS(rc)) { unsigned idxKrnlModInfo = 0; RTDIRENTRY DirEnt; rc = RTDirRead(hDir, &DirEnt, NULL); while (RT_SUCCESS(rc)) { if (!RTDirEntryIsStdDotLink(&DirEnt)) { rc = rtKrnlModLinuxInfoCreate(DirEnt.szName, &pahKrnlModInfo[idxKrnlModInfo]); if (RT_SUCCESS(rc)) idxKrnlModInfo++; } if (RT_SUCCESS(rc)) rc = RTDirRead(hDir, &DirEnt, NULL); } if (rc == VERR_NO_MORE_FILES) rc = VINF_SUCCESS; else if (RT_FAILURE(rc)) { /* Rollback */ while (idxKrnlModInfo-- > 0) RTKrnlModInfoRelease(pahKrnlModInfo[idxKrnlModInfo]); } if (*pcEntries) *pcEntries = cKmodsLoaded; RTDirClose(hDir); } return rc; } RTDECL(uint32_t) RTKrnlModInfoRetain(RTKRNLMODINFO hKrnlModInfo) { PRTKRNLMODINFOINT pThis = hKrnlModInfo; AssertPtrReturn(pThis, UINT32_MAX); uint32_t cRefs = ASMAtomicIncU32(&pThis->cRefs); AssertMsg(cRefs > 1 && cRefs < _1M, ("%#x %p\n", cRefs, pThis)); return cRefs; } RTDECL(uint32_t) RTKrnlModInfoRelease(RTKRNLMODINFO hKrnlModInfo) { PRTKRNLMODINFOINT pThis = hKrnlModInfo; if (!pThis) return 0; AssertPtrReturn(pThis, UINT32_MAX); uint32_t cRefs = ASMAtomicDecU32(&pThis->cRefs); AssertMsg(cRefs < _1M, ("%#x %p\n", cRefs, pThis)); if (cRefs == 0) rtKrnlModInfoDestroy(pThis); return cRefs; } RTDECL(uint32_t) RTKrnlModInfoGetRefCnt(RTKRNLMODINFO hKrnlModInfo) { PRTKRNLMODINFOINT pThis = hKrnlModInfo; AssertPtrReturn(pThis, 0); return pThis->cRefKrnlMod; } RTDECL(const char *) RTKrnlModInfoGetName(RTKRNLMODINFO hKrnlModInfo) { PRTKRNLMODINFOINT pThis = hKrnlModInfo; AssertPtrReturn(pThis, NULL); return &pThis->achName[0]; } RTDECL(const char *) RTKrnlModInfoGetFilePath(RTKRNLMODINFO hKrnlModInfo) { PRTKRNLMODINFOINT pThis = hKrnlModInfo; AssertPtrReturn(pThis, NULL); return NULL; } RTDECL(size_t) RTKrnlModInfoGetSize(RTKRNLMODINFO hKrnlModInfo) { PRTKRNLMODINFOINT pThis = hKrnlModInfo; AssertPtrReturn(pThis, 0); return pThis->cbKrnlMod; } RTDECL(RTR0UINTPTR) RTKrnlModInfoGetLoadAddr(RTKRNLMODINFO hKrnlModInfo) { PRTKRNLMODINFOINT pThis = hKrnlModInfo; AssertPtrReturn(pThis, 0); return pThis->uLoadAddr; } RTDECL(int) RTKrnlModInfoQueryRefModInfo(RTKRNLMODINFO hKrnlModInfo, uint32_t idx, PRTKRNLMODINFO phKrnlModInfoRef) { RT_NOREF3(hKrnlModInfo, idx, phKrnlModInfoRef); return VERR_NOT_IMPLEMENTED; }