/* $Id: DBGFR3PlugIn.cpp 96407 2022-08-22 17:43:14Z vboxsync $ */ /** @file * DBGF - Debugger Facility, Plug-In Support. */ /* * Copyright (C) 2008-2022 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 . * * SPDX-License-Identifier: GPL-3.0-only */ /********************************************************************************************************************************* * Header Files * *********************************************************************************************************************************/ #define LOG_GROUP LOG_GROUP_DBGF #include #include #include #include "DBGFInternal.h" #include #include #include #include #include #include #include #include #include #include #include #include #include /********************************************************************************************************************************* * Defined Constants And Macros * *********************************************************************************************************************************/ #define DBGF_PLUG_IN_READ_LOCK(pUVM) \ do { int rcLock = RTCritSectRwEnterShared(&pUVM->dbgf.s.CritSect); AssertRC(rcLock); } while (0) #define DBGF_PLUG_IN_READ_UNLOCK(pUVM) \ do { int rcLock = RTCritSectRwLeaveShared(&pUVM->dbgf.s.CritSect); AssertRC(rcLock); } while (0) #define DBGF_PLUG_IN_WRITE_LOCK(pUVM) \ do { int rcLock = RTCritSectRwEnterExcl(&pUVM->dbgf.s.CritSect); AssertRC(rcLock); } while (0) #define DBGF_PLUG_IN_WRITE_UNLOCK(pUVM) \ do { int rcLock = RTCritSectRwLeaveExcl(&pUVM->dbgf.s.CritSect); AssertRC(rcLock); } while (0) /** Max allowed length of a plug-in name (excludes the path and suffix). */ #define DBGFPLUGIN_MAX_NAME 64 /********************************************************************************************************************************* * Structures and Typedefs * *********************************************************************************************************************************/ /** * Plug-in tracking record. */ typedef struct DBGFPLUGIN { /** Pointer to the next plug-in. */ struct DBGFPLUGIN *pNext; /** The loader handle. */ RTLDRMOD hLdrMod; /** The plug-in entry point. */ PFNDBGFPLUGIN pfnEntry; /** The name length. */ uint8_t cchName; /** The plug-in name (variable length). */ char szName[1]; } DBGFPLUGIN; /** Pointer to plug-in tracking record. */ typedef DBGFPLUGIN *PDBGFPLUGIN; /********************************************************************************************************************************* * Internal Functions * *********************************************************************************************************************************/ static DECLCALLBACK(void) dbgfPlugInUnloadAll(PUVM pUVM); static FNDBGFHANDLERINT dbgfR3PlugInInfoList; /** * Internal init routine called by DBGFR3Init(). * * @returns VBox status code. * @param pUVM The user mode VM handle. */ int dbgfR3PlugInInit(PUVM pUVM) { return DBGFR3InfoRegisterInternal(pUVM->pVM, "plugins", "Lists the debugger plug-ins.", dbgfR3PlugInInfoList); } /** * Internal cleanup routine called by DBGFR3Term(). * * @param pUVM The user mode VM handle. */ void dbgfR3PlugInTerm(PUVM pUVM) { dbgfPlugInUnloadAll(pUVM); } /** * Extracts the plug-in name from a plug-in specifier that may or may not * include path and/or suffix. * * @returns VBox status code. * * @param pszDst Where to return the name. At least DBGFPLUGIN_MAX_NAME * worth of buffer space. * @param pszPlugIn The plug-in module specifier to parse. * @param pErrInfo Optional error information structure. */ static int dbgfPlugInExtractName(char *pszDst, const char *pszPlugIn, PRTERRINFO pErrInfo) { /* * Parse out the name stopping at the extension. */ const char *pszName = RTPathFilename(pszPlugIn); if (!pszName || !*pszName) return VERR_INVALID_NAME; if (!RTStrNICmp(pszName, RT_STR_TUPLE(DBGF_PLUG_IN_PREFIX))) { pszName += sizeof(DBGF_PLUG_IN_PREFIX) - 1; if (!*pszName) return RTErrInfoSetF(pErrInfo, VERR_INVALID_NAME, "Invalid plug-in name: nothing after the prefix"); } int ch; size_t cchName = 0; while ( (ch = pszName[cchName]) != '\0' && ch != '.') { if ( RT_C_IS_ALPHA(ch) || (RT_C_IS_DIGIT(ch) && cchName != 0)) cchName++; else { if (!RT_C_IS_DIGIT(ch)) return RTErrInfoSetF(pErrInfo, VERR_INVALID_NAME, "Invalid plug-in name: '%c' is not alphanumeric", ch); return RTErrInfoSetF(pErrInfo, VERR_INVALID_NAME, "Invalid plug-in name: Cannot start with a digit (after the prefix)"); } } if (cchName >= DBGFPLUGIN_MAX_NAME) return RTErrInfoSetF(pErrInfo, VERR_INVALID_NAME, "Invalid plug-in name: too long (max %u)", DBGFPLUGIN_MAX_NAME); /* * We're very picky about the extension when present. */ if ( ch == '.' && RTStrICmp(&pszName[cchName], RTLdrGetSuff())) return RTErrInfoSetF(pErrInfo, VERR_INVALID_NAME, "Invalid plug-in name: Suffix isn't the default dll/so/dylib one (%s): '%s'", RTLdrGetSuff(), &pszName[cchName]); /* * Copy it. */ memcpy(pszDst, pszName, cchName); pszDst[cchName] = '\0'; return VINF_SUCCESS; } /** * Locate a loaded plug-in. * * @returns Pointer to the plug-in tracking structure. * @param pUVM Pointer to the user-mode VM structure. * @param pszName The name of the plug-in we're looking for. * @param ppPrev Where to optionally return the pointer to the * previous list member. */ static PDBGFPLUGIN dbgfR3PlugInLocate(PUVM pUVM, const char *pszName, PDBGFPLUGIN *ppPrev) { PDBGFPLUGIN pPrev = NULL; PDBGFPLUGIN pCur = pUVM->dbgf.s.pPlugInHead; while (pCur) { if (!RTStrICmp(pCur->szName, pszName)) { if (ppPrev) *ppPrev = pPrev; return pCur; } /* advance */ pPrev = pCur; pCur = pCur->pNext; } return NULL; } /** * Try load the specified plug-in module. * * @returns VINF_SUCCESS on success, path error or loader error on failure. * * @param pPlugIn The plug-in tracing record. * @param pszModule Module name. * @param pErrInfo Optional error information structure. */ static int dbgfR3PlugInTryLoad(PDBGFPLUGIN pPlugIn, const char *pszModule, PRTERRINFO pErrInfo) { /* * Load it and try resolve the entry point. */ int rc = SUPR3HardenedVerifyPlugIn(pszModule, pErrInfo); if (RT_SUCCESS(rc)) rc = RTLdrLoadEx(pszModule, &pPlugIn->hLdrMod, RTLDRLOAD_FLAGS_LOCAL, pErrInfo); if (RT_SUCCESS(rc)) { rc = RTLdrGetSymbol(pPlugIn->hLdrMod, DBGF_PLUG_IN_ENTRYPOINT, (void **)&pPlugIn->pfnEntry); if (RT_SUCCESS(rc)) { LogRel(("DBGF: Loaded Plug-In '%s' (%s)\n", pPlugIn->szName, pszModule)); return VINF_SUCCESS; } RTErrInfoSet(pErrInfo, rc, "Failed to locate plug-in entrypoint (" DBGF_PLUG_IN_ENTRYPOINT ")" ); LogRel(("DBGF: RTLdrGetSymbol('%s', '%s',) -> %Rrc\n", pszModule, DBGF_PLUG_IN_ENTRYPOINT, rc)); RTLdrClose(pPlugIn->hLdrMod); pPlugIn->hLdrMod = NIL_RTLDRMOD; } return rc; } /** * RTPathTraverseList callback. * * @returns See FNRTPATHTRAVERSER. * * @param pchPath See FNRTPATHTRAVERSER. * @param cchPath See FNRTPATHTRAVERSER. * @param pvUser1 The plug-in specifier. * @param pvUser2 The plug-in tracking record. */ static DECLCALLBACK(int) dbgfR3PlugInLoadCallback(const char *pchPath, size_t cchPath, void *pvUser1, void *pvUser2) { PDBGFPLUGIN pPlugIn = (PDBGFPLUGIN)pvUser1; PRTERRINFO pErrInfo = (PRTERRINFO)pvUser2; /* * Join the path and the specified plug-in name, adding prefix and suffix. */ const char *pszSuff = RTLdrGetSuff(); size_t const cchSuff = strlen(pszSuff); size_t const cchModule = cchPath + sizeof(RTPATH_SLASH_STR) + sizeof(DBGF_PLUG_IN_PREFIX) + pPlugIn->cchName + cchSuff + 4; char *pszModule = (char *)alloca(cchModule); AssertReturn(pszModule, VERR_TRY_AGAIN); memcpy(pszModule, pchPath, cchPath); pszModule[cchPath] = '\0'; int rc = RTPathAppend(pszModule, cchModule, DBGF_PLUG_IN_PREFIX); AssertRCReturn(rc, VERR_TRY_AGAIN); strcat(&pszModule[cchPath], pPlugIn->szName); strcat(&pszModule[cchPath + sizeof(DBGF_PLUG_IN_PREFIX) - 1 + pPlugIn->cchName], pszSuff); Assert(strlen(pszModule) < cchModule - 4); if (RTPathExists(pszModule)) { rc = dbgfR3PlugInTryLoad(pPlugIn, pszModule, pErrInfo); if (RT_SUCCESS(rc)) return VINF_SUCCESS; } return VERR_TRY_AGAIN; } /** * Loads a plug-in. * * @returns VBox status code. * @param pUVM Pointer to the user-mode VM structure. * @param pszName The plug-in name. * @param pszMaybeModule Path to the plug-in, or just the * plug-in name as specified by the user. Ignored * if no path. * @param pErrInfo Optional error information structure. */ static DECLCALLBACK(int) dbgfR3PlugInLoad(PUVM pUVM, const char *pszName, const char *pszMaybeModule, PRTERRINFO pErrInfo) { DBGF_PLUG_IN_WRITE_LOCK(pUVM); /* * Check if a plug-in by the given name already exists. */ PDBGFPLUGIN pPlugIn = dbgfR3PlugInLocate(pUVM, pszName, NULL); if (pPlugIn) { DBGF_PLUG_IN_WRITE_UNLOCK(pUVM); return RTErrInfoSetF(pErrInfo, VERR_ALREADY_EXISTS, "A plug-in by the name '%s' already exists", pszName); } /* * Create a module structure and we can pass around via RTPathTraverseList if needed. */ size_t cbName = strlen(pszName) + 1; pPlugIn = (PDBGFPLUGIN)MMR3HeapAllocZU(pUVM, MM_TAG_DBGF, RT_UOFFSETOF_DYN(DBGFPLUGIN, szName[cbName])); if (RT_UNLIKELY(!pPlugIn)) { DBGF_PLUG_IN_WRITE_UNLOCK(pUVM); return VERR_NO_MEMORY; } memcpy(pPlugIn->szName, pszName, cbName); pPlugIn->cchName = (uint8_t)cbName - 1; Assert(pPlugIn->cchName == cbName - 1); /* * If the caller specified a path, try load exactly what was specified. */ int rc; if (RTPathHavePath(pszMaybeModule)) rc = dbgfR3PlugInTryLoad(pPlugIn, pszMaybeModule, pErrInfo); else { /* * No path specified, search for the plug-in using the canonical * module name for it. */ RTErrInfoClear(pErrInfo); /* 1. The private architecture directory. */ char szPath[_4K]; rc = RTPathAppPrivateArch(szPath, sizeof(szPath)); if (RT_SUCCESS(rc)) rc = RTPathTraverseList(szPath, '\0', dbgfR3PlugInLoadCallback, pPlugIn, pErrInfo); if (RT_FAILURE_NP(rc)) { /* 2. The config value 'PlugInPath' */ int rc2 = CFGMR3QueryString(CFGMR3GetChild(CFGMR3GetRootU(pUVM), "/DBGF"), "PlugInPath", szPath, sizeof(szPath)); if (RT_SUCCESS(rc2)) rc = RTPathTraverseList(szPath, ';', dbgfR3PlugInLoadCallback, pPlugIn, pErrInfo); if (RT_FAILURE_NP(rc)) { /* 3. The VBOXDBG_PLUG_IN_PATH environment variable. */ rc2 = RTEnvGetEx(RTENV_DEFAULT, "VBOXDBG_PLUG_IN_PATH", szPath, sizeof(szPath), NULL); if (RT_SUCCESS(rc2)) rc = RTPathTraverseList(szPath, ';', dbgfR3PlugInLoadCallback, pPlugIn, pErrInfo); } } if (rc == VERR_END_OF_STRING) rc = VERR_FILE_NOT_FOUND; if (pErrInfo && !RTErrInfoIsSet(pErrInfo)) RTErrInfoSetF(pErrInfo, rc, "Failed to locate '%s'", pPlugIn->szName); } if (RT_SUCCESS(rc)) { /* * Try initialize it. */ rc = pPlugIn->pfnEntry(DBGFPLUGINOP_INIT, pUVM, VMMR3GetVTable(), VBOX_VERSION); if (RT_SUCCESS(rc)) { /* * Link it and we're good. */ pPlugIn->pNext = pUVM->dbgf.s.pPlugInHead; pUVM->dbgf.s.pPlugInHead = pPlugIn; DBGF_PLUG_IN_WRITE_UNLOCK(pUVM); return VINF_SUCCESS; } RTErrInfoSet(pErrInfo, rc, "Plug-in init failed"); LogRel(("DBGF: Plug-in '%s' failed during init: %Rrc\n", pPlugIn->szName, rc)); RTLdrClose(pPlugIn->hLdrMod); } MMR3HeapFree(pPlugIn); DBGF_PLUG_IN_WRITE_UNLOCK(pUVM); return rc; } /** * Load a debugging plug-in. * * @returns VBox status code. * @retval VERR_ALREADY_EXISTS if the module was already loaded. * @retval VINF_BUFFER_OVERFLOW if the actual plug-in name buffer was too small * (the plug-in was still successfully loaded). * @param pUVM Pointer to the user-mode VM structure. * @param pszPlugIn The plug-in name. This may specify the exact path to * the plug-in module, or it may just specify the core name * of the plug-in without prefix, suffix and path. * @param pszActual Buffer to return the actual plug-in name in. Optional. * This will be returned on VERR_ALREADY_EXSIST too. * @param cbActual The size of @a pszActual. * @param pErrInfo Optional error information structure. */ VMMR3DECL(int) DBGFR3PlugInLoad(PUVM pUVM, const char *pszPlugIn, char *pszActual, size_t cbActual, PRTERRINFO pErrInfo) { UVM_ASSERT_VALID_EXT_RETURN(pUVM, VERR_INVALID_VM_HANDLE); AssertPtrReturn(pszPlugIn, VERR_INVALID_PARAMETER); /* * Extract the plug-in name. Copy it to the return buffer as we'll want to * return it in the VERR_ALREADY_EXISTS case too. */ char szName[DBGFPLUGIN_MAX_NAME]; int rc = dbgfPlugInExtractName(szName, pszPlugIn, pErrInfo); if (RT_SUCCESS(rc)) { int rc2 = VINF_SUCCESS; if (pszActual) rc2 = RTStrCopy(pszActual, cbActual, szName); /* * Write lock releated DBGF bits and try load it. */ rc = VMR3ReqPriorityCallWaitU(pUVM, 0 /*idDstCpu*/, (PFNRT)dbgfR3PlugInLoad, 4, pUVM, szName, pszPlugIn, pErrInfo); if (rc2 != VINF_SUCCESS && RT_SUCCESS(rc)) rc = VINF_BUFFER_OVERFLOW; } return rc; } /** * Load all plug-ins from the architechture private directory of VBox. * * @param pUVM Pointer to the user-mode VM structure. */ VMMR3DECL(void) DBGFR3PlugInLoadAll(PUVM pUVM) { UVM_ASSERT_VALID_EXT_RETURN_VOID(pUVM); /* * Pass it on to EMT(0) if necessary (thanks to DBGFR3Os*). */ if (VMR3GetVMCPUId(pUVM->pVM) != 0) { VMR3ReqPriorityCallVoidWaitU(pUVM, 0 /*idDstCpu*/, (PFNRT)DBGFR3PlugInLoadAll, 1, pUVM); return; } /* * Open the architecture specific directory with a filter on our prefix * and names including a dot. */ const char *pszSuff = RTLdrGetSuff(); size_t cchSuff = strlen(pszSuff); char szPath[RTPATH_MAX]; int rc = RTPathAppPrivateArch(szPath, sizeof(szPath) - cchSuff); AssertRCReturnVoid(rc); size_t offDir = strlen(szPath); rc = RTPathAppend(szPath, sizeof(szPath) - cchSuff, DBGF_PLUG_IN_PREFIX "*"); AssertRCReturnVoid(rc); strcat(szPath, pszSuff); RTDIR hDir; rc = RTDirOpenFiltered(&hDir, szPath, RTDIRFILTER_WINNT, 0 /*fFlags*/); if (RT_SUCCESS(rc)) { /* * Now read it and try load each of the plug-in modules. */ RTDIRENTRY DirEntry; while (RT_SUCCESS(RTDirRead(hDir, &DirEntry, NULL))) { szPath[offDir] = '\0'; rc = RTPathAppend(szPath, sizeof(szPath), DirEntry.szName); if (RT_SUCCESS(rc)) { char szName[DBGFPLUGIN_MAX_NAME]; rc = dbgfPlugInExtractName(szName, DirEntry.szName, NULL); if (RT_SUCCESS(rc)) { DBGF_PLUG_IN_WRITE_LOCK(pUVM); dbgfR3PlugInLoad(pUVM, szName, szPath, NULL); DBGF_PLUG_IN_WRITE_UNLOCK(pUVM); } } } RTDirClose(hDir); } } /** * Unloads a plug-in by name (no path, prefix or suffix). * * @returns VBox status code. * @retval VERR_NOT_FOUND if the specified plug-in wasn't found. * @param pUVM Pointer to the user-mode VM structure. * @param pszName The name of the plug-in to unload. */ VMMR3DECL(int) DBGFR3PlugInUnload(PUVM pUVM, const char *pszName) { UVM_ASSERT_VALID_EXT_RETURN(pUVM, VERR_INVALID_VM_HANDLE); /* * Pass it on to EMT(0) if necessary (thanks to DBGFR3Os*). */ if (VMR3GetVMCPUId(pUVM->pVM) != 0) return VMR3ReqPriorityCallWaitU(pUVM, 0 /*idDstCpu*/, (PFNRT)DBGFR3PlugInUnload, 2, pUVM, pszName); /* * Find the plug-in. */ DBGF_PLUG_IN_WRITE_LOCK(pUVM); int rc; PDBGFPLUGIN pPrevPlugIn; PDBGFPLUGIN pPlugIn = dbgfR3PlugInLocate(pUVM, pszName, &pPrevPlugIn); if (pPlugIn) { /* * Unlink, terminate, unload and free the plug-in. */ if (pPrevPlugIn) pPrevPlugIn->pNext = pPlugIn->pNext; else pUVM->dbgf.s.pPlugInHead = pPlugIn->pNext; pPlugIn->pfnEntry(DBGFPLUGINOP_TERM, pUVM, VMMR3GetVTable(), 0); RTLdrClose(pPlugIn->hLdrMod); pPlugIn->pfnEntry = NULL; pPlugIn->hLdrMod = NIL_RTLDRMOD; MMR3HeapFree(pPlugIn->pNext); rc = VINF_SUCCESS; } else rc = VERR_NOT_FOUND; DBGF_PLUG_IN_WRITE_UNLOCK(pUVM); return rc; } /** * Unload all plug-ins. * * @param pUVM Pointer to the user-mode VM structure. */ static DECLCALLBACK(void) dbgfPlugInUnloadAll(PUVM pUVM) { DBGF_PLUG_IN_WRITE_LOCK(pUVM); while (pUVM->dbgf.s.pPlugInHead) { PDBGFPLUGIN pPlugin = pUVM->dbgf.s.pPlugInHead; pUVM->dbgf.s.pPlugInHead = pPlugin->pNext; pPlugin->pfnEntry(DBGFPLUGINOP_TERM, pUVM, VMMR3GetVTable(), 0); int rc2 = RTLdrClose(pPlugin->hLdrMod); AssertRC(rc2); pPlugin->pfnEntry = NULL; pPlugin->hLdrMod = NIL_RTLDRMOD; MMR3HeapFree(pPlugin); } DBGF_PLUG_IN_WRITE_UNLOCK(pUVM); } /** * Unloads all plug-ins. * * @param pUVM Pointer to the user-mode VM structure. */ VMMR3DECL(void) DBGFR3PlugInUnloadAll(PUVM pUVM) { UVM_ASSERT_VALID_EXT_RETURN_VOID(pUVM); /* Thanks to DBGFR3Os, this must be done on EMT(0). */ VMR3ReqPriorityCallVoidWaitU(pUVM, 0 /*idDstCpu*/, (PFNRT)dbgfPlugInUnloadAll, 1, pUVM); } /** * @callback_method_impl{FNDBGFHANDLERINT, The 'plugins' info item.} */ static DECLCALLBACK(void) dbgfR3PlugInInfoList(PVM pVM, PCDBGFINFOHLP pHlp, const char *pszArgs) { PDBGFPLUGIN pPlugIn = pVM->pUVM->dbgf.s.pPlugInHead; RT_NOREF_PV(pszArgs); if (pPlugIn) { pHlp->pfnPrintf(pHlp, "Debugging plug-in%s: %s", pPlugIn->pNext ? "s" : "", pPlugIn->szName); while ((pPlugIn = pPlugIn->pNext) != NULL) pHlp->pfnPrintf(pHlp, ", %s", pPlugIn->szName); pHlp->pfnPrintf(pHlp, "\n"); } else pHlp->pfnPrintf(pHlp, "No plug-ins loaded\n"); }