SUPR3HardenedVerify.cpp@ 68033

Last change on this file since 68033 was 66842, checked in by vboxsync, 8 years ago
Support/Hardening: Use realpath() to get absolute paths upon encountering the first symlinks
Property svn:eol-style set to `native` Property svn:keywords set to `Author Date Id Revision`
File size: 83.4 KB

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1	/* $Id: SUPR3HardenedVerify.cpp 66842 2017-05-08 21:03:57Z vboxsync $ */
2	/** @file
3	* VirtualBox Support Library - Verification of Hardened Installation.
4	*/
5
6	/*
7	* Copyright (C) 2006-2016 Oracle Corporation
8	*
9	* This file is part of VirtualBox Open Source Edition (OSE), as
10	* available from http://www.virtualbox.org. This file is free software;
11	* you can redistribute it and/or modify it under the terms of the GNU
12	* General Public License (GPL) as published by the Free Software
13	* Foundation, in version 2 as it comes in the "COPYING" file of the
14	* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
15	* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
16	*
17	* The contents of this file may alternatively be used under the terms
18	* of the Common Development and Distribution License Version 1.0
19	* (CDDL) only, as it comes in the "COPYING.CDDL" file of the
20	* VirtualBox OSE distribution, in which case the provisions of the
21	* CDDL are applicable instead of those of the GPL.
22	*
23	* You may elect to license modified versions of this file under the
24	* terms and conditions of either the GPL or the CDDL or both.
25	*/
26
27
28	/*********************************************************************************************************************************
29	* Header Files *
30	*********************************************************************************************************************************/
31	#if defined(RT_OS_OS2)
32	# define INCL_BASE
33	# define INCL_ERRORS
34	# include <os2.h>
35	# include <stdio.h>
36	# include <stdlib.h>
37	# include <unistd.h>
38	# include <sys/fcntl.h>
39	# include <sys/errno.h>
40	# include <sys/syslimits.h>
41
42	#elif defined(RT_OS_WINDOWS)
43	# include <iprt/nt/nt-and-windows.h>
44	# ifndef IN_SUP_HARDENED_R3
45	# include <stdio.h>
46	# endif
47
48	#else /* UNIXes */
49	# include <sys/types.h>
50	# include <stdio.h>
51	# include <stdlib.h>
52	# include <dirent.h>
53	# include <dlfcn.h>
54	# include <fcntl.h>
55	# include <limits.h>
56	# include <errno.h>
57	# include <unistd.h>
58	# include <sys/stat.h>
59	# include <sys/time.h>
60	# include <sys/fcntl.h>
61	# include <pwd.h>
62	# ifdef RT_OS_DARWIN
63	# include <mach-o/dyld.h>
64	# endif
65
66	#endif
67
68	#include <VBox/sup.h>
69	#include <VBox/err.h>
70	#include <iprt/asm.h>
71	#include <iprt/ctype.h>
72	#include <iprt/param.h>
73	#include <iprt/path.h>
74	#include <iprt/string.h>
75
76	#include "SUPLibInternal.h"
77	#if defined(RT_OS_WINDOWS) && defined(VBOX_WITH_HARDENING)
78	# define SUPHNTVI_NO_NT_STUFF
79	# include "win/SUPHardenedVerify-win.h"
80	#endif
81
82
83	/*********************************************************************************************************************************
84	* Defined Constants And Macros *
85	*********************************************************************************************************************************/
86	/** The max path length acceptable for a trusted path. */
87	#define SUPR3HARDENED_MAX_PATH 260U
88
89	/** Enable to resolve symlinks using realpath() instead of cooking our own stuff. */
90	#define SUP_HARDENED_VERIFY_FOLLOW_SYMLINKS_USE_REALPATH 1
91
92	#ifdef RT_OS_SOLARIS
93	# define dirfd(d) ((d)->d_fd)
94	#endif
95
96	/** Compare table file names with externally supplied names. */
97	#if defined(RT_OS_WINDOWS) \|\| defined(RT_OS_OS2)
98	# define SUP_COMP_FILENAME RTStrICmp
99	#else
100	# define SUP_COMP_FILENAME suplibHardenedStrCmp
101	#endif
102
103
104	/*********************************************************************************************************************************
105	* Global Variables *
106	*********************************************************************************************************************************/
107	/**
108	* The files that gets verified.
109	*
110	* @todo This needs reviewing against the linux packages.
111	* @todo The excessive use of kSupID_AppSharedLib needs to be reviewed at some point. For
112	* the time being we're building the linux packages with SharedLib pointing to
113	* AppPrivArch (lazy bird).
114	*
115	* @remarks If you add executables here, you might need to update
116	* g_apszSupNtVpAllowedVmExes in SUPHardenedVerifyProcess-win.cpp.
117	*/
118	static SUPINSTFILE const g_aSupInstallFiles[] =
119	{
120	/* type, dir, fOpt, "pszFile" */
121	/* ---------------------------------------------------------------------- */
122	{ kSupIFT_Dll, kSupID_AppPrivArch, false, "VMMR0.r0" },
123	{ kSupIFT_Dll, kSupID_AppPrivArch, false, "VBoxDDR0.r0" },
124	{ kSupIFT_Dll, kSupID_AppPrivArch, false, "VBoxDD2R0.r0" },
125
126	#ifdef VBOX_WITH_RAW_MODE
127	{ kSupIFT_Rc, kSupID_AppPrivArch, false, "VMMRC.rc" },
128	{ kSupIFT_Rc, kSupID_AppPrivArch, false, "VBoxDDRC.rc" },
129	{ kSupIFT_Rc, kSupID_AppPrivArch, false, "VBoxDD2RC.rc" },
130	#endif
131
132	{ kSupIFT_Dll, kSupID_AppSharedLib, false, "VBoxRT" SUPLIB_DLL_SUFF },
133	{ kSupIFT_Dll, kSupID_AppSharedLib, false, "VBoxVMM" SUPLIB_DLL_SUFF },
134	#ifdef VBOX_WITH_REM
135	{ kSupIFT_Dll, kSupID_AppSharedLib, false, "VBoxREM" SUPLIB_DLL_SUFF },
136	#endif
137	#if HC_ARCH_BITS == 32
138	{ kSupIFT_Dll, kSupID_AppSharedLib, true, "VBoxREM32" SUPLIB_DLL_SUFF },
139	{ kSupIFT_Dll, kSupID_AppSharedLib, true, "VBoxREM64" SUPLIB_DLL_SUFF },
140	#endif
141	{ kSupIFT_Dll, kSupID_AppSharedLib, false, "VBoxDD" SUPLIB_DLL_SUFF },
142	{ kSupIFT_Dll, kSupID_AppSharedLib, false, "VBoxDD2" SUPLIB_DLL_SUFF },
143	{ kSupIFT_Dll, kSupID_AppSharedLib, false, "VBoxDDU" SUPLIB_DLL_SUFF },
144	{ kSupIFT_Exe, kSupID_AppBin, true, "VBoxVMMPreload" SUPLIB_EXE_SUFF },
145	{ kSupIFT_Dll, kSupID_AppPrivArch, true, "VBoxVMMPreload" SUPLIB_DLL_SUFF },
146
147	//#ifdef VBOX_WITH_DEBUGGER_GUI
148	{ kSupIFT_Dll, kSupID_AppSharedLib, true, "VBoxDbg" SUPLIB_DLL_SUFF },
149	{ kSupIFT_Dll, kSupID_AppSharedLib, true, "VBoxDbg3" SUPLIB_DLL_SUFF },
150	//#endif
151
152	//#ifdef VBOX_WITH_SHARED_CLIPBOARD
153	{ kSupIFT_Dll, kSupID_AppPrivArch, true, "VBoxSharedClipboard" SUPLIB_DLL_SUFF },
154	//#endif
155	//#ifdef VBOX_WITH_SHARED_FOLDERS
156	{ kSupIFT_Dll, kSupID_AppPrivArch, true, "VBoxSharedFolders" SUPLIB_DLL_SUFF },
157	//#endif
158	//#ifdef VBOX_WITH_DRAG_AND_DROP
159	{ kSupIFT_Dll, kSupID_AppPrivArch, true, "VBoxDragAndDropSvc" SUPLIB_DLL_SUFF },
160	//#endif
161	//#ifdef VBOX_WITH_GUEST_PROPS
162	{ kSupIFT_Dll, kSupID_AppPrivArch, true, "VBoxGuestPropSvc" SUPLIB_DLL_SUFF },
163	//#endif
164	//#ifdef VBOX_WITH_GUEST_CONTROL
165	{ kSupIFT_Dll, kSupID_AppPrivArch, true, "VBoxGuestControlSvc" SUPLIB_DLL_SUFF },
166	//#endif
167	{ kSupIFT_Dll, kSupID_AppPrivArch, true, "VBoxHostChannel" SUPLIB_DLL_SUFF },
168	{ kSupIFT_Dll, kSupID_AppPrivArch, true, "VBoxSharedCrOpenGL" SUPLIB_DLL_SUFF },
169	{ kSupIFT_Dll, kSupID_AppPrivArch, true, "VBoxOGLhostcrutil" SUPLIB_DLL_SUFF },
170	{ kSupIFT_Dll, kSupID_AppPrivArch, true, "VBoxOGLhosterrorspu" SUPLIB_DLL_SUFF },
171	{ kSupIFT_Dll, kSupID_AppPrivArch, true, "VBoxOGLrenderspu" SUPLIB_DLL_SUFF },
172
173	{ kSupIFT_Exe, kSupID_AppBin, true, "VBoxManage" SUPLIB_EXE_SUFF },
174
175	#ifdef VBOX_WITH_MAIN
176	{ kSupIFT_Exe, kSupID_AppBin, false, "VBoxSVC" SUPLIB_EXE_SUFF },
177	#ifdef RT_OS_WINDOWS
178	{ kSupIFT_Dll, kSupID_AppSharedLib, false, "VBoxC" SUPLIB_DLL_SUFF },
179	#else
180	{ kSupIFT_Exe, kSupID_AppPrivArch, false, "VBoxXPCOMIPCD" SUPLIB_EXE_SUFF },
181	{ kSupIFT_Dll, kSupID_AppSharedLib, false, "VBoxXPCOM" SUPLIB_DLL_SUFF },
182	{ kSupIFT_Dll, kSupID_AppPrivArchComp, false, "VBoxXPCOMIPCC" SUPLIB_DLL_SUFF },
183	{ kSupIFT_Dll, kSupID_AppPrivArchComp, false, "VBoxC" SUPLIB_DLL_SUFF },
184	{ kSupIFT_Dll, kSupID_AppPrivArchComp, false, "VBoxSVCM" SUPLIB_DLL_SUFF },
185	{ kSupIFT_Data, kSupID_AppPrivArchComp, false, "VBoxXPCOMBase.xpt" },
186	#endif
187	#endif
188
189	{ kSupIFT_Dll, kSupID_AppSharedLib, true, "VRDPAuth" SUPLIB_DLL_SUFF },
190	{ kSupIFT_Dll, kSupID_AppSharedLib, true, "VBoxAuth" SUPLIB_DLL_SUFF },
191	{ kSupIFT_Dll, kSupID_AppSharedLib, true, "VBoxVRDP" SUPLIB_DLL_SUFF },
192
193	//#ifdef VBOX_WITH_HEADLESS
194	{ kSupIFT_Exe, kSupID_AppBin, true, "VBoxHeadless" SUPLIB_EXE_SUFF },
195	{ kSupIFT_Dll, kSupID_AppPrivArch, true, "VBoxHeadless" SUPLIB_DLL_SUFF },
196	{ kSupIFT_Dll, kSupID_AppPrivArch, true, "VBoxVideoRecFB" SUPLIB_DLL_SUFF },
197	//#endif
198
199	//#ifdef VBOX_WITH_QTGUI
200	{ kSupIFT_Exe, kSupID_AppBin, true, "VirtualBox" SUPLIB_EXE_SUFF },
201	{ kSupIFT_Dll, kSupID_AppPrivArch, true, "VirtualBox" SUPLIB_DLL_SUFF },
202	# ifdef RT_OS_DARWIN
203	{ kSupIFT_Exe, kSupID_AppBin, true, "VirtualBoxVM" SUPLIB_EXE_SUFF },
204	# endif
205	# if !defined(RT_OS_DARWIN) && !defined(RT_OS_WINDOWS) && !defined(RT_OS_OS2)
206	{ kSupIFT_Dll, kSupID_AppSharedLib, true, "VBoxKeyboard" SUPLIB_DLL_SUFF },
207	# endif
208	//#endif
209
210	//#ifdef VBOX_WITH_VBOXSDL
211	{ kSupIFT_Exe, kSupID_AppBin, true, "VBoxSDL" SUPLIB_EXE_SUFF },
212	{ kSupIFT_Dll, kSupID_AppPrivArch, true, "VBoxSDL" SUPLIB_DLL_SUFF },
213	//#endif
214
215	//#ifdef VBOX_WITH_WEBSERVICES
216	{ kSupIFT_Exe, kSupID_AppBin, true, "vboxwebsrv" SUPLIB_EXE_SUFF },
217	//#endif
218
219	#ifdef RT_OS_LINUX
220	{ kSupIFT_Exe, kSupID_AppBin, true, "VBoxTunctl" SUPLIB_EXE_SUFF },
221	#endif
222
223	//#ifdef VBOX_WITH_NETFLT
224	{ kSupIFT_Exe, kSupID_AppBin, true, "VBoxNetDHCP" SUPLIB_EXE_SUFF },
225	{ kSupIFT_Dll, kSupID_AppPrivArch, true, "VBoxNetDHCP" SUPLIB_DLL_SUFF },
226	//#endif
227
228	//#ifdef VBOX_WITH_LWIP_NAT
229	{ kSupIFT_Exe, kSupID_AppBin, true, "VBoxNetNAT" SUPLIB_EXE_SUFF },
230	{ kSupIFT_Dll, kSupID_AppPrivArch, true, "VBoxNetNAT" SUPLIB_DLL_SUFF },
231	//#endif
232	#if defined(VBOX_WITH_HARDENING) && defined(RT_OS_WINDOWS)
233	# define HARDENED_TESTCASE_BIN_ENTRY(a_szName) \
234	{ kSupIFT_TestExe, kSupID_AppBin, true, a_szName SUPLIB_EXE_SUFF }, \
235	{ kSupIFT_TestDll, kSupID_AppBin, true, a_szName SUPLIB_DLL_SUFF }
236	HARDENED_TESTCASE_BIN_ENTRY("tstMicro"),
237	HARDENED_TESTCASE_BIN_ENTRY("tstPDMAsyncCompletion"),
238	HARDENED_TESTCASE_BIN_ENTRY("tstPDMAsyncCompletionStress"),
239	HARDENED_TESTCASE_BIN_ENTRY("tstVMM"),
240	HARDENED_TESTCASE_BIN_ENTRY("tstVMREQ"),
241	# define HARDENED_TESTCASE_ENTRY(a_szName) \
242	{ kSupIFT_TestExe, kSupID_Testcase, true, a_szName SUPLIB_EXE_SUFF }, \
243	{ kSupIFT_TestDll, kSupID_Testcase, true, a_szName SUPLIB_DLL_SUFF }
244	HARDENED_TESTCASE_ENTRY("tstCFGM"),
245	HARDENED_TESTCASE_ENTRY("tstGIP-2"),
246	HARDENED_TESTCASE_ENTRY("tstIntNet-1"),
247	HARDENED_TESTCASE_ENTRY("tstMMHyperHeap"),
248	HARDENED_TESTCASE_ENTRY("tstRTR0ThreadPreemptionDriver"),
249	HARDENED_TESTCASE_ENTRY("tstRTR0MemUserKernelDriver"),
250	HARDENED_TESTCASE_ENTRY("tstRTR0SemMutexDriver"),
251	HARDENED_TESTCASE_ENTRY("tstRTR0TimerDriver"),
252	HARDENED_TESTCASE_ENTRY("tstSSM"),
253	#endif
254	};
255
256
257	/** Array parallel to g_aSupInstallFiles containing per-file status info. */
258	static SUPVERIFIEDFILE g_aSupVerifiedFiles[RT_ELEMENTS(g_aSupInstallFiles)];
259
260	/** Array index by install directory specifier containing info about verified directories. */
261	static SUPVERIFIEDDIR g_aSupVerifiedDirs[kSupID_End];
262
263
264	/**
265	* Assembles the path to a directory.
266	*
267	* @returns VINF_SUCCESS on success, some error code on failure (fFatal
268	* decides whether it returns or not).
269	*
270	* @param enmDir The directory.
271	* @param pszDst Where to assemble the path.
272	* @param cchDst The size of the buffer.
273	* @param fFatal Whether failures should be treated as fatal (true) or not (false).
274	*/
275	static int supR3HardenedMakePath(SUPINSTDIR enmDir, char *pszDst, size_t cchDst, bool fFatal)
276	{
277	int rc;
278	switch (enmDir)
279	{
280	case kSupID_AppBin:
281	rc = supR3HardenedPathAppBin(pszDst, cchDst);
282	break;
283	case kSupID_AppSharedLib:
284	rc = supR3HardenedPathAppSharedLibs(pszDst, cchDst);
285	break;
286	case kSupID_AppPrivArch:
287	rc = supR3HardenedPathAppPrivateArch(pszDst, cchDst);
288	break;
289	case kSupID_AppPrivArchComp:
290	rc = supR3HardenedPathAppPrivateArch(pszDst, cchDst);
291	if (RT_SUCCESS(rc))
292	{
293	size_t off = suplibHardenedStrLen(pszDst);
294	if (cchDst - off >= sizeof("/components"))
295	suplibHardenedMemCopy(&pszDst[off], "/components", sizeof("/components"));
296	else
297	rc = VERR_BUFFER_OVERFLOW;
298	}
299	break;
300	case kSupID_AppPrivNoArch:
301	rc = supR3HardenedPathAppPrivateNoArch(pszDst, cchDst);
302	break;
303	case kSupID_Testcase:
304	rc = supR3HardenedPathAppBin(pszDst, cchDst);
305	if (RT_SUCCESS(rc))
306	{
307	size_t off = suplibHardenedStrLen(pszDst);
308	if (cchDst - off >= sizeof("/testcase"))
309	suplibHardenedMemCopy(&pszDst[off], "/testcase", sizeof("/testcase"));
310	else
311	rc = VERR_BUFFER_OVERFLOW;
312	}
313	break;
314	default:
315	return supR3HardenedError(VERR_INTERNAL_ERROR, fFatal,
316	"supR3HardenedMakePath: enmDir=%d\n", enmDir);
317	}
318	if (RT_FAILURE(rc))
319	supR3HardenedError(rc, fFatal,
320	"supR3HardenedMakePath: enmDir=%d rc=%d\n", enmDir, rc);
321	return rc;
322	}
323
324
325
326	/**
327	* Assembles the path to a file table entry, with or without the actual filename.
328	*
329	* @returns VINF_SUCCESS on success, some error code on failure (fFatal
330	* decides whether it returns or not).
331	*
332	* @param pFile The file table entry.
333	* @param pszDst Where to assemble the path.
334	* @param cchDst The size of the buffer.
335	* @param fWithFilename If set, the filename is included, otherwise it is omitted (no trailing slash).
336	* @param fFatal Whether failures should be treated as fatal (true) or not (false).
337	*/
338	static int supR3HardenedMakeFilePath(PCSUPINSTFILE pFile, char *pszDst, size_t cchDst, bool fWithFilename, bool fFatal)
339	{
340	/*
341	* Combine supR3HardenedMakePath and the filename.
342	*/
343	int rc = supR3HardenedMakePath(pFile->enmDir, pszDst, cchDst, fFatal);
344	if (RT_SUCCESS(rc) && fWithFilename)
345	{
346	size_t cchFile = suplibHardenedStrLen(pFile->pszFile);
347	size_t off = suplibHardenedStrLen(pszDst);
348	if (cchDst - off >= cchFile + 2)
349	{
350	pszDst[off++] = '/';
351	suplibHardenedMemCopy(&pszDst[off], pFile->pszFile, cchFile + 1);
352	}
353	else
354	rc = supR3HardenedError(VERR_BUFFER_OVERFLOW, fFatal,
355	"supR3HardenedMakeFilePath: pszFile=%s off=%lu\n",
356	pFile->pszFile, (long)off);
357	}
358	return rc;
359	}
360
361
362	/**
363	* Verifies a directory.
364	*
365	* @returns VINF_SUCCESS on success. On failure, an error code is returned if
366	* fFatal is clear and if it's set the function wont return.
367	* @param enmDir The directory specifier.
368	* @param fFatal Whether validation failures should be treated as
369	* fatal (true) or not (false).
370	*/
371	DECLHIDDEN(int) supR3HardenedVerifyFixedDir(SUPINSTDIR enmDir, bool fFatal)
372	{
373	/*
374	* Validate the index just to be on the safe side...
375	*/
376	if (enmDir <= kSupID_Invalid \|\| enmDir >= kSupID_End)
377	return supR3HardenedError(VERR_INTERNAL_ERROR, fFatal,
378	"supR3HardenedVerifyDir: enmDir=%d\n", enmDir);
379
380	/*
381	* Already validated?
382	*/
383	if (g_aSupVerifiedDirs[enmDir].fValidated)
384	return VINF_SUCCESS; /** @todo revalidate? */
385
386	/* initialize the entry. */
387	if (g_aSupVerifiedDirs[enmDir].hDir != 0)
388	supR3HardenedError(VERR_INTERNAL_ERROR, fFatal,
389	"supR3HardenedVerifyDir: hDir=%p enmDir=%d\n",
390	(void *)g_aSupVerifiedDirs[enmDir].hDir, enmDir);
391	g_aSupVerifiedDirs[enmDir].hDir = -1;
392	g_aSupVerifiedDirs[enmDir].fValidated = false;
393
394	/*
395	* Make the path and open the directory.
396	*/
397	char szPath[RTPATH_MAX];
398	int rc = supR3HardenedMakePath(enmDir, szPath, sizeof(szPath), fFatal);
399	if (RT_SUCCESS(rc))
400	{
401	#if defined(RT_OS_WINDOWS)
402	PRTUTF16 pwszPath;
403	rc = RTStrToUtf16(szPath, &pwszPath);
404	if (RT_SUCCESS(rc))
405	{
406	HANDLE hDir = CreateFileW(pwszPath,
407	GENERIC_READ,
408	FILE_SHARE_READ \| FILE_SHARE_DELETE \| FILE_SHARE_WRITE,
409	NULL,
410	OPEN_EXISTING,
411	FILE_ATTRIBUTE_NORMAL \| FILE_FLAG_BACKUP_SEMANTICS,
412	NULL);
413	if (hDir != INVALID_HANDLE_VALUE)
414	{
415	/** @todo check the type */
416	/* That's all on windows, for now at least... */
417	g_aSupVerifiedDirs[enmDir].hDir = (intptr_t)hDir;
418	g_aSupVerifiedDirs[enmDir].fValidated = true;
419	}
420	else if (enmDir == kSupID_Testcase)
421	{
422	g_aSupVerifiedDirs[enmDir].fValidated = true;
423	rc = VINF_SUCCESS; /* Optional directory, ignore if missing. */
424	}
425	else
426	{
427	int err = RtlGetLastWin32Error();
428	rc = supR3HardenedError(VERR_PATH_NOT_FOUND, fFatal,
429	"supR3HardenedVerifyDir: Failed to open \"%s\": err=%d\n",
430	szPath, err);
431	}
432	RTUtf16Free(pwszPath);
433	}
434	else
435	rc = supR3HardenedError(rc, fFatal,
436	"supR3HardenedVerifyDir: Failed to convert \"%s\" to UTF-16: err=%d\n", szPath, rc);
437
438	#else /* UNIXY */
439	int fd = open(szPath, O_RDONLY, 0);
440	if (fd >= 0)
441	{
442	/*
443	* On unixy systems we'll make sure the directory is owned by root
444	* and not writable by the group and user.
445	*/
446	struct stat st;
447	if (!fstat(fd, &st))
448	{
449
450	if ( st.st_uid == 0
451	&& !(st.st_mode & (S_IWGRP \| S_IWOTH))
452	&& S_ISDIR(st.st_mode))
453	{
454	g_aSupVerifiedDirs[enmDir].hDir = fd;
455	g_aSupVerifiedDirs[enmDir].fValidated = true;
456	}
457	else
458	{
459	if (!S_ISDIR(st.st_mode))
460	rc = supR3HardenedError(VERR_NOT_A_DIRECTORY, fFatal,
461	"supR3HardenedVerifyDir: \"%s\" is not a directory\n",
462	szPath, (long)st.st_uid);
463	else if (st.st_uid)
464	rc = supR3HardenedError(VERR_ACCESS_DENIED, fFatal,
465	"supR3HardenedVerifyDir: Cannot trust the directory \"%s\": not owned by root (st_uid=%ld)\n",
466	szPath, (long)st.st_uid);
467	else
468	rc = supR3HardenedError(VERR_ACCESS_DENIED, fFatal,
469	"supR3HardenedVerifyDir: Cannot trust the directory \"%s\": group and/or other writable (st_mode=0%lo)\n",
470	szPath, (long)st.st_mode);
471	close(fd);
472	}
473	}
474	else
475	{
476	int err = errno;
477	rc = supR3HardenedError(VERR_ACCESS_DENIED, fFatal,
478	"supR3HardenedVerifyDir: Failed to fstat \"%s\": %s (%d)\n",
479	szPath, strerror(err), err);
480	close(fd);
481	}
482	}
483	else if (enmDir == kSupID_Testcase)
484	{
485	g_aSupVerifiedDirs[enmDir].fValidated = true;
486	rc = VINF_SUCCESS; /* Optional directory, ignore if missing. */
487	}
488	else
489	{
490	int err = errno;
491	rc = supR3HardenedError(VERR_PATH_NOT_FOUND, fFatal,
492	"supR3HardenedVerifyDir: Failed to open \"%s\": %s (%d)\n",
493	szPath, strerror(err), err);
494	}
495	#endif /* UNIXY */
496	}
497
498	return rc;
499	}
500
501
502	#ifdef RT_OS_WINDOWS
503	/**
504	* Opens the file for verification.
505	*
506	* @returns VINF_SUCCESS on success. On failure, an error code is returned if
507	* fFatal is clear and if it's set the function wont return.
508	* @param pFile The file entry.
509	* @param fFatal Whether validation failures should be treated as
510	* kl fatal (true) or not (false).
511	* @param phFile The file handle, set to -1 if we failed to open
512	* the file. The function may return VINF_SUCCESS
513	* and a -1 handle if the file is optional.
514	*/
515	static int supR3HardenedVerifyFileOpen(PCSUPINSTFILE pFile, bool fFatal, intptr_t *phFile)
516	{
517	*phFile = -1;
518
519	char szPath[RTPATH_MAX];
520	int rc = supR3HardenedMakeFilePath(pFile, szPath, sizeof(szPath), true /fWithFilename/, fFatal);
521	if (RT_SUCCESS(rc))
522	{
523	PRTUTF16 pwszPath;
524	rc = RTStrToUtf16(szPath, &pwszPath);
525	if (RT_SUCCESS(rc))
526	{
527	HANDLE hFile = CreateFileW(pwszPath,
528	GENERIC_READ,
529	FILE_SHARE_READ,
530	NULL,
531	OPEN_EXISTING,
532	FILE_ATTRIBUTE_NORMAL,
533	NULL);
534	if (hFile != INVALID_HANDLE_VALUE)
535	{
536	*phFile = (intptr_t)hFile;
537	rc = VINF_SUCCESS;
538	}
539	else
540	{
541	int err = RtlGetLastWin32Error();
542	if ( !pFile->fOptional
543	\|\| ( err != ERROR_FILE_NOT_FOUND
544	&& (err != ERROR_PATH_NOT_FOUND \|\| pFile->enmDir != kSupID_Testcase) ) )
545	rc = supR3HardenedError(VERR_PATH_NOT_FOUND, fFatal,
546	"supR3HardenedVerifyFileInternal: Failed to open '%s': err=%d\n", szPath, err);
547	}
548	RTUtf16Free(pwszPath);
549	}
550	else
551	rc = supR3HardenedError(rc, fFatal, "supR3HardenedVerifyFileInternal: Failed to convert '%s' to UTF-16: %Rrc\n",
552	szPath, rc);
553	}
554	return rc;
555	}
556
557
558	/**
559	* Worker for supR3HardenedVerifyFileInternal.
560	*
561	* @returns VINF_SUCCESS on success. On failure, an error code is returned if
562	* fFatal is clear and if it's set the function wont return.
563	* @param pFile The file entry.
564	* @param pVerified The verification record.
565	* @param fFatal Whether validation failures should be treated as
566	* fatal (true) or not (false).
567	* @param fLeaveFileOpen Whether the file should be left open.
568	*/
569	static int supR3HardenedVerifyFileSignature(PCSUPINSTFILE pFile, PSUPVERIFIEDFILE pVerified, bool fFatal, bool fLeaveFileOpen)
570	{
571	# if defined(VBOX_WITH_HARDENING) && !defined(IN_SUP_R3_STATIC) /* Latter: Not in VBoxCpuReport and friends. */
572
573	/*
574	* Open the file if we have to.
575	*/
576	int rc;
577	intptr_t hFileOpened;
578	intptr_t hFile = pVerified->hFile;
579	if (hFile != -1)
580	hFileOpened = -1;
581	else
582	{
583	rc = supR3HardenedVerifyFileOpen(pFile, fFatal, &hFileOpened);
584	if (RT_FAILURE(rc))
585	return rc;
586	hFile = hFileOpened;
587	}
588
589	/*
590	* Verify the signature.
591	*/
592	char szErr[1024];
593	RTERRINFO ErrInfo;
594	RTErrInfoInit(&ErrInfo, szErr, sizeof(szErr));
595
596	uint32_t fFlags = SUPHNTVI_F_REQUIRE_BUILD_CERT;
597	if (pFile->enmType == kSupIFT_Rc)
598	fFlags \|= SUPHNTVI_F_RC_IMAGE;
599
600	rc = supHardenedWinVerifyImageByHandleNoName((HANDLE)hFile, fFlags, &ErrInfo);
601	if (RT_SUCCESS(rc))
602	pVerified->fCheckedSignature = true;
603	else
604	{
605	pVerified->fCheckedSignature = false;
606	rc = supR3HardenedError(rc, fFatal, "supR3HardenedVerifyFileInternal: '%s': Image verify error rc=%Rrc: %s\n",
607	pFile->pszFile, rc, szErr);
608
609	}
610
611	/*
612	* Close the handle if we opened the file and we should close it.
613	*/
614	if (hFileOpened != -1)
615	{
616	if (fLeaveFileOpen && RT_SUCCESS(rc))
617	pVerified->hFile = hFileOpened;
618	else
619	NtClose((HANDLE)hFileOpened);
620	}
621
622	return rc;
623
624	# else /* Not checking signatures. */
625	RT_NOREF4(pFile, pVerified, fFatal, fLeaveFileOpen);
626	return VINF_SUCCESS;
627	# endif /* Not checking signatures. */
628	}
629	#endif
630
631
632	/**
633	* Verifies a file entry.
634	*
635	* @returns VINF_SUCCESS on success. On failure, an error code is returned if
636	* fFatal is clear and if it's set the function wont return.
637	*
638	* @param iFile The file table index of the file to be verified.
639	* @param fFatal Whether validation failures should be treated as
640	* fatal (true) or not (false).
641	* @param fLeaveFileOpen Whether the file should be left open.
642	* @param fVerifyAll Set if this is an verify all call and we will
643	* postpone signature checking.
644	*/
645	static int supR3HardenedVerifyFileInternal(int iFile, bool fFatal, bool fLeaveFileOpen, bool fVerifyAll)
646	{
647	#ifndef RT_OS_WINDOWS
648	RT_NOREF1(fVerifyAll);
649	#endif
650	PCSUPINSTFILE pFile = &g_aSupInstallFiles[iFile];
651	PSUPVERIFIEDFILE pVerified = &g_aSupVerifiedFiles[iFile];
652
653	/*
654	* Already done validation? Do signature validation if we haven't yet.
655	*/
656	if (pVerified->fValidated)
657	{
658	/** @todo revalidate? Check that the file hasn't been replace or similar. */
659	#ifdef RT_OS_WINDOWS
660	if (!pVerified->fCheckedSignature && !fVerifyAll)
661	return supR3HardenedVerifyFileSignature(pFile, pVerified, fFatal, fLeaveFileOpen);
662	#endif
663	return VINF_SUCCESS;
664	}
665
666
667	/* initialize the entry. */
668	if (pVerified->hFile != 0)
669	supR3HardenedError(VERR_INTERNAL_ERROR, fFatal,
670	"supR3HardenedVerifyFileInternal: hFile=%p (%s)\n",
671	(void *)pVerified->hFile, pFile->pszFile);
672	pVerified->hFile = -1;
673	pVerified->fValidated = false;
674	#ifdef RT_OS_WINDOWS
675	pVerified->fCheckedSignature = false;
676	#endif
677
678	/*
679	* Verify the directory then proceed to open it.
680	* (This'll make sure the directory is opened and that we can (later)
681	* use openat if we wish.)
682	*/
683	int rc = supR3HardenedVerifyFixedDir(pFile->enmDir, fFatal);
684	if (RT_SUCCESS(rc))
685	{
686	#if defined(RT_OS_WINDOWS)
687	rc = supR3HardenedVerifyFileOpen(pFile, fFatal, &pVerified->hFile);
688	if (RT_SUCCESS(rc))
689	{
690	if (!fVerifyAll)
691	rc = supR3HardenedVerifyFileSignature(pFile, pVerified, fFatal, fLeaveFileOpen);
692	if (RT_SUCCESS(rc))
693	{
694	pVerified->fValidated = true;
695	if (!fLeaveFileOpen)
696	{
697	NtClose((HANDLE)pVerified->hFile);
698	pVerified->hFile = -1;
699	}
700	}
701	}
702	#else /* !RT_OS_WINDOWS */
703	char szPath[RTPATH_MAX];
704	rc = supR3HardenedMakeFilePath(pFile, szPath, sizeof(szPath), true /fWithFilename/, fFatal);
705	if (RT_SUCCESS(rc))
706	{
707	int fd = open(szPath, O_RDONLY, 0);
708	if (fd >= 0)
709	{
710	/*
711	* On unixy systems we'll make sure the file is owned by root
712	* and not writable by the group and user.
713	*/
714	struct stat st;
715	if (!fstat(fd, &st))
716	{
717	if ( st.st_uid == 0
718	&& !(st.st_mode & (S_IWGRP \| S_IWOTH))
719	&& S_ISREG(st.st_mode))
720	{
721	/* it's valid. */
722	if (fLeaveFileOpen)
723	pVerified->hFile = fd;
724	else
725	close(fd);
726	pVerified->fValidated = true;
727	}
728	else
729	{
730	if (!S_ISREG(st.st_mode))
731	rc = supR3HardenedError(VERR_IS_A_DIRECTORY, fFatal,
732	"supR3HardenedVerifyFileInternal: \"%s\" is not a regular file\n",
733	szPath, (long)st.st_uid);
734	else if (st.st_uid)
735	rc = supR3HardenedError(VERR_ACCESS_DENIED, fFatal,
736	"supR3HardenedVerifyFileInternal: Cannot trust the file \"%s\": not owned by root (st_uid=%ld)\n",
737	szPath, (long)st.st_uid);
738	else
739	rc = supR3HardenedError(VERR_ACCESS_DENIED, fFatal,
740	"supR3HardenedVerifyFileInternal: Cannot trust the file \"%s\": group and/or other writable (st_mode=0%lo)\n",
741	szPath, (long)st.st_mode);
742	close(fd);
743	}
744	}
745	else
746	{
747	int err = errno;
748	rc = supR3HardenedError(VERR_ACCESS_DENIED, fFatal,
749	"supR3HardenedVerifyFileInternal: Failed to fstat \"%s\": %s (%d)\n",
750	szPath, strerror(err), err);
751	close(fd);
752	}
753	}
754	else
755	{
756	int err = errno;
757	if (!pFile->fOptional \|\| err != ENOENT)
758	rc = supR3HardenedError(VERR_PATH_NOT_FOUND, fFatal,
759	"supR3HardenedVerifyFileInternal: Failed to open \"%s\": %s (%d)\n",
760	szPath, strerror(err), err);
761	}
762	}
763	#endif /* !RT_OS_WINDOWS */
764	}
765
766	return rc;
767	}
768
769
770	/**
771	* Verifies that the specified table entry matches the given filename.
772	*
773	* @returns VINF_SUCCESS if matching. On mismatch fFatal indicates whether an
774	* error is returned or we terminate the application.
775	*
776	* @param iFile The file table index.
777	* @param pszFilename The filename.
778	* @param fFatal Whether validation failures should be treated as
779	* fatal (true) or not (false).
780	*/
781	static int supR3HardenedVerifySameFile(int iFile, const char *pszFilename, bool fFatal)
782	{
783	PCSUPINSTFILE pFile = &g_aSupInstallFiles[iFile];
784
785	/*
786	* Construct the full path for the file table entry
787	* and compare it with the specified file.
788	*/
789	char szName[RTPATH_MAX];
790	int rc = supR3HardenedMakeFilePath(pFile, szName, sizeof(szName), true /fWithFilename/, fFatal);
791	if (RT_FAILURE(rc))
792	return rc;
793	if (SUP_COMP_FILENAME(szName, pszFilename))
794	{
795	/*
796	* Normalize the two paths and compare again.
797	*/
798	rc = VERR_NOT_SAME_DEVICE;
799	#if defined(RT_OS_WINDOWS)
800	LPSTR pszIgnored;
801	char szName2[RTPATH_MAX]; /** @todo Must use UTF-16 here! Code is mixing UTF-8 and native. */
802	if ( GetFullPathName(szName, RT_ELEMENTS(szName2), &szName2[0], &pszIgnored)
803	&& GetFullPathName(pszFilename, RT_ELEMENTS(szName), &szName[0], &pszIgnored))
804	if (!SUP_COMP_FILENAME(szName2, szName))
805	rc = VINF_SUCCESS;
806	#else
807	AssertCompile(RTPATH_MAX >= PATH_MAX);
808	char szName2[RTPATH_MAX];
809	if ( realpath(szName, szName2) != NULL
810	&& realpath(pszFilename, szName) != NULL)
811	if (!SUP_COMP_FILENAME(szName2, szName))
812	rc = VINF_SUCCESS;
813	#endif
814
815	if (RT_FAILURE(rc))
816	{
817	supR3HardenedMakeFilePath(pFile, szName, sizeof(szName), true /fWithFilename/, fFatal);
818	return supR3HardenedError(rc, fFatal,
819	"supR3HardenedVerifySameFile: \"%s\" isn't the same as \"%s\"\n",
820	pszFilename, szName);
821	}
822	}
823
824	/*
825	* Check more stuff like the stat info if it's an already open file?
826	*/
827
828
829
830	return VINF_SUCCESS;
831	}
832
833
834	/**
835	* Verifies a file.
836	*
837	* @returns VINF_SUCCESS on success.
838	* VERR_NOT_FOUND if the file isn't in the table, this isn't ever a fatal error.
839	* On verification failure, an error code will be returned when fFatal is clear,
840	* otherwise the program will be terminated.
841	*
842	* @param pszFilename The filename.
843	* @param fFatal Whether validation failures should be treated as
844	* fatal (true) or not (false).
845	*/
846	DECLHIDDEN(int) supR3HardenedVerifyFixedFile(const char *pszFilename, bool fFatal)
847	{
848	/*
849	* Lookup the file and check if it's the same file.
850	*/
851	const char *pszName = supR3HardenedPathFilename(pszFilename);
852	for (unsigned iFile = 0; iFile < RT_ELEMENTS(g_aSupInstallFiles); iFile++)
853	if (!SUP_COMP_FILENAME(pszName, g_aSupInstallFiles[iFile].pszFile))
854	{
855	int rc = supR3HardenedVerifySameFile(iFile, pszFilename, fFatal);
856	if (RT_SUCCESS(rc))
857	rc = supR3HardenedVerifyFileInternal(iFile, fFatal, false /* fLeaveFileOpen /, false / fVerifyAll */);
858	return rc;
859	}
860
861	return VERR_NOT_FOUND;
862	}
863
864
865	/**
866	* Verifies a program, worker for supR3HardenedVerifyAll.
867	*
868	* @returns See supR3HardenedVerifyAll.
869	* @param pszProgName See supR3HardenedVerifyAll.
870	* @param pszExePath The path to the executable.
871	* @param fFatal See supR3HardenedVerifyAll.
872	* @param fLeaveOpen The leave open setting used by
873	* supR3HardenedVerifyAll.
874	* @param fMainFlags Flags supplied to SUPR3HardenedMain.
875	*/
876	static int supR3HardenedVerifyProgram(const char pszProgName, const char pszExePath, bool fFatal,
877	bool fLeaveOpen, uint32_t fMainFlags)
878	{
879	/*
880	* Search the table looking for the executable and the DLL/DYLIB/SO.
881	* Note! On darwin we have a hack in place for VirtualBoxVM helper app
882	* to share VirtualBox.dylib with the VirtualBox app. This ASSUMES
883	* that cchProgNameDll is equal or shorter to the exe name.
884	*/
885	int rc = VINF_SUCCESS;
886	bool fExe = false;
887	bool fDll = false;
888	size_t const cchProgNameExe = suplibHardenedStrLen(pszProgName);
889	#ifndef RT_OS_DARWIN
890	size_t const cchProgNameDll = cchProgNameExe;
891	NOREF(fMainFlags);
892	#else
893	size_t const cchProgNameDll = fMainFlags & SUPSECMAIN_FLAGS_OSX_VM_APP
894	? sizeof("VirtualBox") - 1
895	: cchProgNameExe;
896	if (cchProgNameDll > cchProgNameExe)
897	return supR3HardenedError(VERR_INTERNAL_ERROR, fFatal,
898	"supR3HardenedVerifyProgram: SUPSECMAIN_FLAGS_OSX_VM_APP + '%s'", pszProgName);
899	#endif
900	for (unsigned iFile = 0; iFile < RT_ELEMENTS(g_aSupInstallFiles); iFile++)
901	if (!suplibHardenedStrNCmp(pszProgName, g_aSupInstallFiles[iFile].pszFile, cchProgNameDll))
902	{
903	if ( ( g_aSupInstallFiles[iFile].enmType == kSupIFT_Dll
904	\|\| g_aSupInstallFiles[iFile].enmType == kSupIFT_TestDll)
905	&& !suplibHardenedStrCmp(&g_aSupInstallFiles[iFile].pszFile[cchProgNameDll], SUPLIB_DLL_SUFF))
906	{
907	/* This only has to be found (once). */
908	if (fDll)
909	rc = supR3HardenedError(VERR_INTERNAL_ERROR, fFatal,
910	"supR3HardenedVerifyProgram: duplicate DLL entry for \"%s\"\n", pszProgName);
911	else
912	rc = supR3HardenedVerifyFileInternal(iFile, fFatal, fLeaveOpen,
913	true /* fVerifyAll - check sign later, only final process need check it on load. */);
914	fDll = true;
915	}
916	else if ( ( g_aSupInstallFiles[iFile].enmType == kSupIFT_Exe
917	\|\| g_aSupInstallFiles[iFile].enmType == kSupIFT_TestExe)
918	&& ( cchProgNameExe == cchProgNameDll
919	\|\| !suplibHardenedStrNCmp(pszProgName, g_aSupInstallFiles[iFile].pszFile, cchProgNameExe))
920	&& !suplibHardenedStrCmp(&g_aSupInstallFiles[iFile].pszFile[cchProgNameExe], SUPLIB_EXE_SUFF))
921	{
922	/* Here we'll have to check that the specific program is the same as the entry. */
923	if (fExe)
924	rc = supR3HardenedError(VERR_INTERNAL_ERROR, fFatal,
925	"supR3HardenedVerifyProgram: duplicate EXE entry for \"%s\"\n", pszProgName);
926	else
927	rc = supR3HardenedVerifyFileInternal(iFile, fFatal, fLeaveOpen, false /* fVerifyAll */);
928	fExe = true;
929
930	supR3HardenedVerifySameFile(iFile, pszExePath, fFatal);
931	}
932	}
933
934	/*
935	* Check the findings.
936	*/
937	if (RT_SUCCESS(rc))
938	{
939	if (!fDll && !fExe)
940	rc = supR3HardenedError(VERR_NOT_FOUND, fFatal,
941	"supR3HardenedVerifyProgram: Couldn't find the program \"%s\"\n", pszProgName);
942	else if (!fExe)
943	rc = supR3HardenedError(VERR_NOT_FOUND, fFatal,
944	"supR3HardenedVerifyProgram: Couldn't find the EXE entry for \"%s\"\n", pszProgName);
945	else if (!fDll)
946	rc = supR3HardenedError(VERR_NOT_FOUND, fFatal,
947	"supR3HardenedVerifyProgram: Couldn't find the DLL entry for \"%s\"\n", pszProgName);
948	}
949	return rc;
950	}
951
952
953	/**
954	* Verifies all the known files (called from SUPR3HardenedMain).
955	*
956	* @returns VINF_SUCCESS on success.
957	* On verification failure, an error code will be returned when fFatal is clear,
958	* otherwise the program will be terminated.
959	*
960	* @param fFatal Whether validation failures should be treated as
961	* fatal (true) or not (false).
962	* @param pszProgName The program name. This is used to verify that
963	* both the executable and corresponding
964	* DLL/DYLIB/SO are valid.
965	* @param pszExePath The path to the executable.
966	* @param fMainFlags Flags supplied to SUPR3HardenedMain.
967	*/
968	DECLHIDDEN(int) supR3HardenedVerifyAll(bool fFatal, const char pszProgName, const char pszExePath, uint32_t fMainFlags)
969	{
970	/*
971	* On windows
972	*/
973	#if defined(RT_OS_WINDOWS)
974	bool fLeaveOpen = true;
975	#else
976	bool fLeaveOpen = false;
977	#endif
978
979	/*
980	* The verify all the files.
981	*/
982	int rc = VINF_SUCCESS;
983	for (unsigned iFile = 0; iFile < RT_ELEMENTS(g_aSupInstallFiles); iFile++)
984	{
985	int rc2 = supR3HardenedVerifyFileInternal(iFile, fFatal, fLeaveOpen, true /* fVerifyAll */);
986	if (RT_FAILURE(rc2) && RT_SUCCESS(rc))
987	rc = rc2;
988	}
989
990	/*
991	* Verify the program name, that is to say, check that it's in the table
992	* (thus verified above) and verify the signature on platforms where we
993	* sign things.
994	*/
995	int rc2 = supR3HardenedVerifyProgram(pszProgName, pszExePath, fFatal, fLeaveOpen, fMainFlags);
996	if (RT_FAILURE(rc2) && RT_SUCCESS(rc))
997	rc2 = rc;
998
999	return rc;
1000	}
1001
1002
1003	/**
1004	* Copies the N messages into the error buffer and returns @a rc.
1005	*
1006	* @returns Returns @a rc
1007	* @param rc The return code.
1008	* @param pErrInfo The error info structure.
1009	* @param cMsgs The number of messages in the ellipsis.
1010	* @param ... Message parts.
1011	*/
1012	static int supR3HardenedSetErrorN(int rc, PRTERRINFO pErrInfo, unsigned cMsgs, ...)
1013	{
1014	if (pErrInfo)
1015	{
1016	size_t cbErr = pErrInfo->cbMsg;
1017	char *pszErr = pErrInfo->pszMsg;
1018
1019	va_list va;
1020	va_start(va, cMsgs);
1021	while (cMsgs-- > 0 && cbErr > 0)
1022	{
1023	const char pszMsg = va_arg(va, const char );
1024	size_t cchMsg = VALID_PTR(pszMsg) ? suplibHardenedStrLen(pszMsg) : 0;
1025	if (cchMsg >= cbErr)
1026	cchMsg = cbErr - 1;
1027	suplibHardenedMemCopy(pszErr, pszMsg, cchMsg);
1028	pszErr[cchMsg] = '\0';
1029	pszErr += cchMsg;
1030	cbErr -= cchMsg;
1031	}
1032	va_end(va);
1033
1034	pErrInfo->rc = rc;
1035	pErrInfo->fFlags \|= RTERRINFO_FLAGS_SET;
1036	}
1037
1038	return rc;
1039	}
1040
1041
1042	#if defined(RT_OS_DARWIN) \|\| defined(RT_OS_LINUX)
1043	/**
1044	* Copies the four messages into the error buffer and returns @a rc.
1045	*
1046	* @returns Returns @a rc
1047	* @param rc The return code.
1048	* @param pErrInfo The error info structure.
1049	* @param pszMsg1 The first message part.
1050	* @param pszMsg2 The second message part.
1051	* @param pszMsg3 The third message part.
1052	* @param pszMsg4 The fourth message part.
1053	*/
1054	static int supR3HardenedSetError4(int rc, PRTERRINFO pErrInfo, const char *pszMsg1,
1055	const char pszMsg2, const char pszMsg3, const char *pszMsg4)
1056	{
1057	return supR3HardenedSetErrorN(rc, pErrInfo, 4, pszMsg1, pszMsg2, pszMsg3, pszMsg4);
1058	}
1059	#endif
1060
1061
1062	/**
1063	* Copies the three messages into the error buffer and returns @a rc.
1064	*
1065	* @returns Returns @a rc
1066	* @param rc The return code.
1067	* @param pErrInfo The error info structure.
1068	* @param pszMsg1 The first message part.
1069	* @param pszMsg2 The second message part.
1070	* @param pszMsg3 The third message part.
1071	*/
1072	static int supR3HardenedSetError3(int rc, PRTERRINFO pErrInfo, const char *pszMsg1,
1073	const char pszMsg2, const char pszMsg3)
1074	{
1075	return supR3HardenedSetErrorN(rc, pErrInfo, 3, pszMsg1, pszMsg2, pszMsg3);
1076	}
1077
1078
1079	#ifdef SOME_UNUSED_FUNCTION
1080	/**
1081	* Copies the two messages into the error buffer and returns @a rc.
1082	*
1083	* @returns Returns @a rc
1084	* @param rc The return code.
1085	* @param pErrInfo The error info structure.
1086	* @param pszMsg1 The first message part.
1087	* @param pszMsg2 The second message part.
1088	*/
1089	static int supR3HardenedSetError2(int rc, PRTERRINFO pErrInfo, const char *pszMsg1,
1090	const char *pszMsg2)
1091	{
1092	return supR3HardenedSetErrorN(rc, pErrInfo, 2, pszMsg1, pszMsg2);
1093	}
1094	#endif
1095
1096
1097	#ifndef SUP_HARDENED_VERIFY_FOLLOW_SYMLINKS_USE_REALPATH
1098	# if defined(RT_OS_DARWIN) \|\| defined(RT_OS_LINUX)
1099	/**
1100	* Copies the error message to the error buffer and returns @a rc.
1101	*
1102	* @returns Returns @a rc
1103	* @param rc The return code.
1104	* @param pErrInfo The error info structure.
1105	* @param pszMsg The message.
1106	*/
1107	static int supR3HardenedSetError(int rc, PRTERRINFO pErrInfo, const char *pszMsg)
1108	{
1109	return supR3HardenedSetErrorN(rc, pErrInfo, 1, pszMsg);
1110	}
1111	# endif
1112	#endif
1113
1114
1115	/**
1116	* Output from a successfull supR3HardenedVerifyPathSanity call.
1117	*/
1118	typedef struct SUPR3HARDENEDPATHINFO
1119	{
1120	/** The length of the path in szCopy. */
1121	uint16_t cch;
1122	/** The number of path components. */
1123	uint16_t cComponents;
1124	/** Set if the path ends with slash, indicating that it's a directory
1125	* reference and not a file reference. The slash has been removed from
1126	* the copy. */
1127	bool fDirSlash;
1128	/** The offset where each path component starts, i.e. the char after the
1129	* slash. The array has cComponents + 1 entries, where the final one is
1130	* cch + 1 so that one can always terminate the current component by
1131	* szPath[aoffComponent[i] - 1] = '\0'. */
1132	uint16_t aoffComponents[32+1];
1133	/** A normalized copy of the path.
1134	* Reserve some extra space so we can be more relaxed about overflow
1135	* checks and terminator paddings, especially when recursing. */
1136	char szPath[SUPR3HARDENED_MAX_PATH * 2];
1137	} SUPR3HARDENEDPATHINFO;
1138	/** Pointer to a parsed path. */
1139	typedef SUPR3HARDENEDPATHINFO *PSUPR3HARDENEDPATHINFO;
1140
1141
1142	/**
1143	* Verifies that the path is absolutely sane, it also parses the path.
1144	*
1145	* A sane path starts at the root (w/ drive letter on DOS derived systems) and
1146	* does not have any relative bits (/../) or unnecessary slashes (/bin//ls).
1147	* Sane paths are less or equal to SUPR3HARDENED_MAX_PATH bytes in length. UNC
1148	* paths are not supported.
1149	*
1150	* @returns VBox status code.
1151	* @param pszPath The path to check.
1152	* @param pErrInfo The error info structure.
1153	* @param pInfo Where to return a copy of the path along with
1154	* parsing information.
1155	*/
1156	static int supR3HardenedVerifyPathSanity(const char *pszPath, PRTERRINFO pErrInfo, PSUPR3HARDENEDPATHINFO pInfo)
1157	{
1158	const char *pszSrc = pszPath;
1159	char *pszDst = pInfo->szPath;
1160
1161	/*
1162	* Check that it's an absolute path and copy the volume/root specifier.
1163	*/
1164	#if defined(RT_OS_WINDOWS) \|\| defined(RT_OS_OS2)
1165	if ( !RT_C_IS_ALPHA(pszSrc[0])
1166	\|\| pszSrc[1] != ':'
1167	\|\| !RTPATH_IS_SLASH(pszSrc[2]))
1168	return supR3HardenedSetError3(VERR_SUPLIB_PATH_NOT_ABSOLUTE, pErrInfo, "The path is not absolute: '", pszPath, "'");
1169
1170	*pszDst++ = RT_C_TO_UPPER(pszSrc[0]);
1171	*pszDst++ = ':';
1172	*pszDst++ = RTPATH_SLASH;
1173	pszSrc += 3;
1174
1175	#else
1176	if (!RTPATH_IS_SLASH(pszSrc[0]))
1177	return supR3HardenedSetError3(VERR_SUPLIB_PATH_NOT_ABSOLUTE, pErrInfo, "The path is not absolute: '", pszPath, "'");
1178
1179	*pszDst++ = RTPATH_SLASH;
1180	pszSrc += 1;
1181	#endif
1182
1183	/*
1184	* No path specifying the root or something very shortly thereafter will
1185	* be approved of.
1186	*/
1187	if (pszSrc[0] == '\0')
1188	return supR3HardenedSetError3(VERR_SUPLIB_PATH_IS_ROOT, pErrInfo, "The path is root: '", pszPath, "'");
1189	if ( pszSrc[1] == '\0'
1190	\|\| pszSrc[2] == '\0')
1191	return supR3HardenedSetError3(VERR_SUPLIB_PATH_TOO_SHORT, pErrInfo, "The path is too short: '", pszPath, "'");
1192
1193	/*
1194	* The root slash should be alone to avoid UNC confusion.
1195	*/
1196	if (RTPATH_IS_SLASH(pszSrc[0]))
1197	return supR3HardenedSetError3(VERR_SUPLIB_PATH_NOT_CLEAN, pErrInfo,
1198	"The path is not clean of leading double slashes: '", pszPath, "'");
1199	/*
1200	* Check each component. No parent references.
1201	*/
1202	pInfo->cComponents = 0;
1203	pInfo->fDirSlash = false;
1204	while (pszSrc[0])
1205	{
1206	/* Sanity checks. */
1207	if ( pszSrc[0] == '.'
1208	&& pszSrc[1] == '.'
1209	&& RTPATH_IS_SLASH(pszSrc[2]))
1210	return supR3HardenedSetError3(VERR_SUPLIB_PATH_NOT_ABSOLUTE, pErrInfo,
1211	"The path is not absolute: '", pszPath, "'");
1212
1213	/* Record the start of the component. */
1214	if (pInfo->cComponents >= RT_ELEMENTS(pInfo->aoffComponents) - 1)
1215	return supR3HardenedSetError3(VERR_SUPLIB_PATH_TOO_MANY_COMPONENTS, pErrInfo,
1216	"The path has too many components: '", pszPath, "'");
1217	pInfo->aoffComponents[pInfo->cComponents++] = pszDst - &pInfo->szPath[0];
1218
1219	/* Traverse to the end of the component, copying it as we go along. */
1220	while (pszSrc[0])
1221	{
1222	if (RTPATH_IS_SLASH(pszSrc[0]))
1223	{
1224	pszSrc++;
1225	if (*pszSrc)
1226	*pszDst++ = RTPATH_SLASH;
1227	else
1228	pInfo->fDirSlash = true;
1229	break;
1230	}
1231	pszDst++ = pszSrc++;
1232	if ((uintptr_t)(pszDst - &pInfo->szPath[0]) >= SUPR3HARDENED_MAX_PATH)
1233	return supR3HardenedSetError3(VERR_SUPLIB_PATH_TOO_LONG, pErrInfo,
1234	"The path is too long: '", pszPath, "'");
1235	}
1236
1237	/* Skip double slashes. */
1238	while (RTPATH_IS_SLASH(*pszSrc))
1239	pszSrc++;
1240	}
1241
1242	/* Terminate the string and enter its length. */
1243	pszDst[0] = '\0';
1244	pszDst[1] = '\0'; /* for aoffComponents */
1245	pInfo->cch = (uint16_t)(pszDst - &pInfo->szPath[0]);
1246	pInfo->aoffComponents[pInfo->cComponents] = pInfo->cch + 1;
1247
1248	return VINF_SUCCESS;
1249	}
1250
1251
1252	/**
1253	* The state information collected by supR3HardenedVerifyFsObject.
1254	*
1255	* This can be used to verify that a directory we've opened for enumeration is
1256	* the same as the one that supR3HardenedVerifyFsObject just verified. It can
1257	* equally be used to verify a native specfied by the user.
1258	*/
1259	typedef struct SUPR3HARDENEDFSOBJSTATE
1260	{
1261	#ifdef RT_OS_WINDOWS
1262	/** Not implemented for windows yet. */
1263	char chTodo;
1264	#else
1265	/** The stat output. */
1266	struct stat Stat;
1267	#endif
1268	} SUPR3HARDENEDFSOBJSTATE;
1269	/** Pointer to a file system object state. */
1270	typedef SUPR3HARDENEDFSOBJSTATE *PSUPR3HARDENEDFSOBJSTATE;
1271	/** Pointer to a const file system object state. */
1272	typedef SUPR3HARDENEDFSOBJSTATE const *PCSUPR3HARDENEDFSOBJSTATE;
1273
1274
1275	/**
1276	* Query information about a file system object by path.
1277	*
1278	* @returns VBox status code, error buffer filled on failure.
1279	* @param pszPath The path to the object.
1280	* @param pFsObjState Where to return the state information.
1281	* @param pErrInfo The error info structure.
1282	*/
1283	static int supR3HardenedQueryFsObjectByPath(char const *pszPath, PSUPR3HARDENEDFSOBJSTATE pFsObjState, PRTERRINFO pErrInfo)
1284	{
1285	#if defined(RT_OS_WINDOWS)
1286	/** @todo Windows hardening. */
1287	pFsObjState->chTodo = 0;
1288	RT_NOREF2(pszPath, pErrInfo);
1289	return VINF_SUCCESS;
1290
1291	#else
1292	/*
1293	* Stat the object, do not follow links.
1294	*/
1295	if (lstat(pszPath, &pFsObjState->Stat) != 0)
1296	{
1297	/* Ignore access errors */
1298	if (errno != EACCES)
1299	return supR3HardenedSetErrorN(VERR_SUPLIB_STAT_FAILED, pErrInfo,
1300	5, "stat failed with ", strerror(errno), " on: '", pszPath, "'");
1301	}
1302
1303	/*
1304	* Read ACLs.
1305	*/
1306	/** @todo */
1307
1308	return VINF_SUCCESS;
1309	#endif
1310	}
1311
1312
1313	/**
1314	* Query information about a file system object by native handle.
1315	*
1316	* @returns VBox status code, error buffer filled on failure.
1317	* @param hNative The native handle to the object @a pszPath
1318	* specifies and this should be verified to be the
1319	* same file system object.
1320	* @param pFsObjState Where to return the state information.
1321	* @param pszPath The path to the object. (For the error message
1322	* only.)
1323	* @param pErrInfo The error info structure.
1324	*/
1325	static int supR3HardenedQueryFsObjectByHandle(RTHCUINTPTR hNative, PSUPR3HARDENEDFSOBJSTATE pFsObjState,
1326	char const *pszPath, PRTERRINFO pErrInfo)
1327	{
1328	#if defined(RT_OS_WINDOWS)
1329	/** @todo Windows hardening. */
1330	pFsObjState->chTodo = 0;
1331	RT_NOREF3(hNative, pszPath, pErrInfo);
1332	return VINF_SUCCESS;
1333
1334	#else
1335	/*
1336	* Stat the object, do not follow links.
1337	*/
1338	if (fstat((int)hNative, &pFsObjState->Stat) != 0)
1339	return supR3HardenedSetErrorN(VERR_SUPLIB_STAT_FAILED, pErrInfo,
1340	5, "fstat failed with ", strerror(errno), " on '", pszPath, "'");
1341
1342	/*
1343	* Read ACLs.
1344	*/
1345	/** @todo */
1346
1347	return VINF_SUCCESS;
1348	#endif
1349	}
1350
1351
1352	/**
1353	* Verifies that the file system object indicated by the native handle is the
1354	* same as the one @a pFsObjState indicates.
1355	*
1356	* @returns VBox status code, error buffer filled on failure.
1357	* @param pFsObjState1 File system object information/state by path.
1358	* @param pFsObjState2 File system object information/state by handle.
1359	* @param pszPath The path to the object @a pFsObjState
1360	* describes. (For the error message.)
1361	* @param pErrInfo The error info structure.
1362	*/
1363	static int supR3HardenedIsSameFsObject(PCSUPR3HARDENEDFSOBJSTATE pFsObjState1, PCSUPR3HARDENEDFSOBJSTATE pFsObjState2,
1364	const char *pszPath, PRTERRINFO pErrInfo)
1365	{
1366	#if defined(RT_OS_WINDOWS)
1367	/** @todo Windows hardening. */
1368	RT_NOREF4(pFsObjState1, pFsObjState2, pszPath, pErrInfo);
1369	return VINF_SUCCESS;
1370
1371	#elif defined(RT_OS_OS2)
1372	RT_NOREF4(pFsObjState1, pFsObjState2, pszPath, pErrInfo);
1373	return VINF_SUCCESS;
1374
1375	#else
1376	/*
1377	* Compare the ino+dev, then the uid+gid and finally the important mode
1378	* bits. Technically the first one should be enough, but we're paranoid.
1379	*/
1380	if ( pFsObjState1->Stat.st_ino != pFsObjState2->Stat.st_ino
1381	\|\| pFsObjState1->Stat.st_dev != pFsObjState2->Stat.st_dev)
1382	return supR3HardenedSetError3(VERR_SUPLIB_NOT_SAME_OBJECT, pErrInfo,
1383	"The native handle is not the same as '", pszPath, "' (ino/dev)");
1384	if ( pFsObjState1->Stat.st_uid != pFsObjState2->Stat.st_uid
1385	\|\| pFsObjState1->Stat.st_gid != pFsObjState2->Stat.st_gid)
1386	return supR3HardenedSetError3(VERR_SUPLIB_NOT_SAME_OBJECT, pErrInfo,
1387	"The native handle is not the same as '", pszPath, "' (uid/gid)");
1388	if ( (pFsObjState1->Stat.st_mode & (S_IFMT \| S_IWUSR \| S_IWGRP \| S_IWOTH))
1389	!= (pFsObjState2->Stat.st_mode & (S_IFMT \| S_IWUSR \| S_IWGRP \| S_IWOTH)))
1390	return supR3HardenedSetError3(VERR_SUPLIB_NOT_SAME_OBJECT, pErrInfo,
1391	"The native handle is not the same as '", pszPath, "' (mode)");
1392	return VINF_SUCCESS;
1393	#endif
1394	}
1395
1396
1397	/**
1398	* Verifies a file system object (file or directory).
1399	*
1400	* @returns VBox status code, error buffer filled on failure.
1401	* @param pFsObjState The file system object information/state to be
1402	* verified.
1403	* @param fDir Whether this is a directory or a file.
1404	* @param fRelaxed Whether we can be more relaxed about this
1405	* directory (only used for grand parent
1406	* directories).
1407	* @param fSymlinksAllowed Flag whether symlinks are allowed or not.
1408	* If allowed the symlink object is verified not the target.
1409	* @param pszPath The path to the object. For error messages and
1410	* securing a couple of hacks.
1411	* @param pErrInfo The error info structure.
1412	*/
1413	static int supR3HardenedVerifyFsObject(PCSUPR3HARDENEDFSOBJSTATE pFsObjState, bool fDir, bool fRelaxed,
1414	bool fSymlinksAllowed, const char *pszPath, PRTERRINFO pErrInfo)
1415	{
1416	#if defined(RT_OS_WINDOWS)
1417	/** @todo Windows hardening. */
1418	RT_NOREF(pFsObjState, fDir, fRelaxed, fSymlinksAllowed, pszPath, pErrInfo);
1419	return VINF_SUCCESS;
1420
1421	#elif defined(RT_OS_OS2)
1422	/* No hardening here - it's a single user system. */
1423	RT_NOREF(pFsObjState, fDir, fRelaxed, fSymlinksAllowed, pszPath, pErrInfo);
1424	return VINF_SUCCESS;
1425
1426	#else
1427	/*
1428	* The owner must be root.
1429	*
1430	* This can be extended to include predefined system users if necessary.
1431	*/
1432	if (pFsObjState->Stat.st_uid != 0)
1433	return supR3HardenedSetError3(VERR_SUPLIB_OWNER_NOT_ROOT, pErrInfo, "The owner is not root: '", pszPath, "'");
1434
1435	/*
1436	* The object type must be directory or file. It can be a symbolic link
1437	* if explicitely allowed. Otherwise this and other risky stuff is not allowed
1438	* (sorry dude, but we're paranoid on purpose here).
1439	*/
1440	if ( !S_ISLNK(pFsObjState->Stat.st_mode)
1441	\|\| !fSymlinksAllowed)
1442	{
1443
1444	if ( !S_ISDIR(pFsObjState->Stat.st_mode)
1445	&& !S_ISREG(pFsObjState->Stat.st_mode))
1446	{
1447	if (S_ISLNK(pFsObjState->Stat.st_mode))
1448	return supR3HardenedSetError3(VERR_SUPLIB_SYMLINKS_ARE_NOT_PERMITTED, pErrInfo,
1449	"Symlinks are not permitted: '", pszPath, "'");
1450	return supR3HardenedSetError3(VERR_SUPLIB_NOT_DIR_NOT_FILE, pErrInfo,
1451	"Not regular file or directory: '", pszPath, "'");
1452	}
1453	if (fDir != !!S_ISDIR(pFsObjState->Stat.st_mode))
1454	{
1455	if (S_ISDIR(pFsObjState->Stat.st_mode))
1456	return supR3HardenedSetError3(VERR_SUPLIB_IS_DIRECTORY, pErrInfo,
1457	"Expected file but found directory: '", pszPath, "'");
1458	return supR3HardenedSetError3(VERR_SUPLIB_IS_FILE, pErrInfo,
1459	"Expected directory but found file: '", pszPath, "'");
1460	}
1461	}
1462
1463	/*
1464	* The group does not matter if it does not have write access, if it has
1465	* write access it must be group 0 (root/wheel/whatever).
1466	*
1467	* This can be extended to include predefined system groups or groups that
1468	* only root is member of.
1469	*/
1470	if ( (pFsObjState->Stat.st_mode & S_IWGRP)
1471	&& pFsObjState->Stat.st_gid != 0)
1472	{
1473	# ifdef RT_OS_DARWIN
1474	/* HACK ALERT: On Darwin /Applications is root:admin with admin having
1475	full access. So, to work around we relax the hardening a bit and
1476	permit grand parents and beyond to be group writable by admin. */
1477	/** @todo dynamically resolve the admin group? */
1478	bool fBad = !fRelaxed \|\| pFsObjState->Stat.st_gid != 80 /admin/ \|\| suplibHardenedStrCmp(pszPath, "/Applications");
1479
1480	# elif defined(RT_OS_FREEBSD)
1481	/* HACK ALERT: PC-BSD 9 has group-writable /usr/pib directory which is
1482	similar to /Applications on OS X (see above).
1483	On FreeBSD root is normally the only member of this group, on
1484	PC-BSD the default user is a member. */
1485	/** @todo dynamically resolve the operator group? */
1486	bool fBad = !fRelaxed \|\| pFsObjState->Stat.st_gid != 5 /operator/ \|\| suplibHardenedStrCmp(pszPath, "/usr/pbi");
1487	NOREF(fRelaxed);
1488	# elif defined(RT_OS_SOLARIS)
1489	/* HACK ALERT: Solaris has group-writable /usr/lib/iconv directory from
1490	which the appropriate module is loaded.
1491	By default only root and daemon are part of that group.
1492	. */
1493	/** @todo dynamically resolve the bin group? */
1494	bool fBad = !fRelaxed \|\| pFsObjState->Stat.st_gid != 2 /bin/ \|\| suplibHardenedStrCmp(pszPath, "/usr/lib/iconv");
1495	# else
1496	NOREF(fRelaxed);
1497	bool fBad = true;
1498	# endif
1499	if (fBad)
1500	return supR3HardenedSetError3(VERR_SUPLIB_WRITE_NON_SYS_GROUP, pErrInfo,
1501	"An unknown (and thus untrusted) group has write access to '", pszPath,
1502	"' and we therefore cannot trust the directory content or that of any subdirectory");
1503	}
1504
1505	/*
1506	* World must not have write access. There is no relaxing this rule.
1507	* Linux exception: Symbolic links are always give permission 0777, there
1508	* is no lchmod or lchown APIs. The permissions on parent
1509	* directory that contains the symbolic link is what is
1510	* decising wrt to modifying it. (Caller is expected not
1511	* to allow symbolic links in the first path component.)
1512	*/
1513	if ( (pFsObjState->Stat.st_mode & S_IWOTH)
1514	# ifdef RT_OS_LINUX
1515	&& ( !S_ISLNK(pFsObjState->Stat.st_mode)
1516	\|\| !fSymlinksAllowed /* paranoia */)
1517	# endif
1518	)
1519	return supR3HardenedSetError3(VERR_SUPLIB_WORLD_WRITABLE, pErrInfo,
1520	"World writable: '", pszPath, "'");
1521
1522	/*
1523	* Check the ACLs.
1524	*/
1525	/** @todo */
1526
1527	return VINF_SUCCESS;
1528	#endif
1529	}
1530
1531
1532	/**
1533	* Verifies that the file system object indicated by the native handle is the
1534	* same as the one @a pFsObjState indicates.
1535	*
1536	* @returns VBox status code, error buffer filled on failure.
1537	* @param hNative The native handle to the object @a pszPath
1538	* specifies and this should be verified to be the
1539	* same file system object.
1540	* @param pFsObjState The information/state returned by a previous
1541	* query call.
1542	* @param pszPath The path to the object @a pFsObjState
1543	* describes. (For the error message.)
1544	* @param pErrInfo The error info structure.
1545	*/
1546	static int supR3HardenedVerifySameFsObject(RTHCUINTPTR hNative, PCSUPR3HARDENEDFSOBJSTATE pFsObjState,
1547	const char *pszPath, PRTERRINFO pErrInfo)
1548	{
1549	SUPR3HARDENEDFSOBJSTATE FsObjState2;
1550	int rc = supR3HardenedQueryFsObjectByHandle(hNative, &FsObjState2, pszPath, pErrInfo);
1551	if (RT_SUCCESS(rc))
1552	rc = supR3HardenedIsSameFsObject(pFsObjState, &FsObjState2, pszPath, pErrInfo);
1553	return rc;
1554	}
1555
1556
1557	/**
1558	* Does the recursive directory enumeration.
1559	*
1560	* @returns VBox status code, error buffer filled on failure.
1561	* @param pszDirPath The path buffer containing the subdirectory to
1562	* enumerate followed by a slash (this is never
1563	* the root slash). The buffer is RTPATH_MAX in
1564	* size and anything starting at @a cchDirPath
1565	* - 1 and beyond is scratch space.
1566	* @param cchDirPath The length of the directory path + slash.
1567	* @param pFsObjState Pointer to the file system object state buffer.
1568	* On input this will hold the stats for
1569	* the directory @a pszDirPath indicates and will
1570	* be used to verified that we're opening the same
1571	* thing.
1572	* @param fRecursive Whether to recurse into subdirectories.
1573	* @param pErrInfo The error info structure.
1574	*/
1575	static int supR3HardenedVerifyDirRecursive(char *pszDirPath, size_t cchDirPath, PSUPR3HARDENEDFSOBJSTATE pFsObjState,
1576	bool fRecursive, PRTERRINFO pErrInfo)
1577	{
1578	#if defined(RT_OS_WINDOWS)
1579	/** @todo Windows hardening. */
1580	RT_NOREF5(pszDirPath, cchDirPath, pFsObjState, fRecursive, pErrInfo);
1581	return VINF_SUCCESS;
1582
1583	#elif defined(RT_OS_OS2)
1584	/* No hardening here - it's a single user system. */
1585	RT_NOREF5(pszDirPath, cchDirPath, pFsObjState, fRecursive, pErrInfo);
1586	return VINF_SUCCESS;
1587
1588	#else
1589	/*
1590	* Open the directory. Now, we could probably eliminate opendir here
1591	* and go down on kernel API level (open + getdents for instance), however
1592	* that's not very portable and hopefully not necessary.
1593	*/
1594	DIR *pDir = opendir(pszDirPath);
1595	if (!pDir)
1596	{
1597	/* Ignore access errors. */
1598	if (errno == EACCES)
1599	return VINF_SUCCESS;
1600	return supR3HardenedSetErrorN(VERR_SUPLIB_DIR_ENUM_FAILED, pErrInfo,
1601	5, "opendir failed with ", strerror(errno), " on '", pszDirPath, "'");
1602	}
1603	if (dirfd(pDir) != -1)
1604	{
1605	int rc = supR3HardenedVerifySameFsObject(dirfd(pDir), pFsObjState, pszDirPath, pErrInfo);
1606	if (RT_FAILURE(rc))
1607	{
1608	closedir(pDir);
1609	return rc;
1610	}
1611	}
1612
1613	/*
1614	* Enumerate the directory, check all the requested bits.
1615	*/
1616	int rc = VINF_SUCCESS;
1617	for (;;)
1618	{
1619	pszDirPath[cchDirPath] = '\0'; /* for error messages. */
1620
1621	struct dirent Entry;
1622	struct dirent *pEntry;
1623	#if RT_GNUC_PREREQ(4, 6)
1624	# pragma GCC diagnostic push
1625	# pragma GCC diagnostic ignored "-Wdeprecated-declarations"
1626	#endif
1627	int iErr = readdir_r(pDir, &Entry, &pEntry);
1628	#if RT_GNUC_PREREQ(4, 6)
1629	# pragma GCC diagnostic pop
1630	#endif
1631	if (iErr)
1632	{
1633	rc = supR3HardenedSetErrorN(VERR_SUPLIB_DIR_ENUM_FAILED, pErrInfo,
1634	5, "readdir_r failed with ", strerror(iErr), " in '", pszDirPath, "'");
1635	break;
1636	}
1637	if (!pEntry)
1638	break;
1639
1640	/*
1641	* Check the length and copy it into the path buffer so it can be
1642	* stat()'ed.
1643	*/
1644	size_t cchName = suplibHardenedStrLen(pEntry->d_name);
1645	if (cchName + cchDirPath > SUPR3HARDENED_MAX_PATH)
1646	{
1647	rc = supR3HardenedSetErrorN(VERR_SUPLIB_PATH_TOO_LONG, pErrInfo,
1648	4, "Path grew too long during recursion: '", pszDirPath, pEntry->d_name, "'");
1649	break;
1650	}
1651	suplibHardenedMemCopy(&pszDirPath[cchName], pEntry->d_name, cchName + 1);
1652
1653	/*
1654	* Query the information about the entry and verify it.
1655	* (We don't bother skipping '.' and '..' at this point, a little bit
1656	* of extra checks doesn't hurt and neither requires relaxed handling.)
1657	*/
1658	rc = supR3HardenedQueryFsObjectByPath(pszDirPath, pFsObjState, pErrInfo);
1659	if (RT_SUCCESS(rc))
1660	break;
1661	rc = supR3HardenedVerifyFsObject(pFsObjState, S_ISDIR(pFsObjState->Stat.st_mode), false /fRelaxed/,
1662	false /fSymlinksAllowed/, pszDirPath, pErrInfo);
1663	if (RT_FAILURE(rc))
1664	break;
1665
1666	/*
1667	* Recurse into subdirectories if requested.
1668	*/
1669	if ( fRecursive
1670	&& S_ISDIR(pFsObjState->Stat.st_mode)
1671	&& suplibHardenedStrCmp(pEntry->d_name, ".")
1672	&& suplibHardenedStrCmp(pEntry->d_name, ".."))
1673	{
1674	pszDirPath[cchDirPath + cchName] = RTPATH_SLASH;
1675	pszDirPath[cchDirPath + cchName + 1] = '\0';
1676
1677	rc = supR3HardenedVerifyDirRecursive(pszDirPath, cchDirPath + cchName + 1, pFsObjState,
1678	fRecursive, pErrInfo);
1679	if (RT_FAILURE(rc))
1680	break;
1681	}
1682	}
1683
1684	closedir(pDir);
1685	return VINF_SUCCESS;
1686	#endif
1687	}
1688
1689
1690	/**
1691	* Worker for SUPR3HardenedVerifyDir.
1692	*
1693	* @returns See SUPR3HardenedVerifyDir.
1694	* @param pszDirPath See SUPR3HardenedVerifyDir.
1695	* @param fRecursive See SUPR3HardenedVerifyDir.
1696	* @param fCheckFiles See SUPR3HardenedVerifyDir.
1697	* @param pErrInfo See SUPR3HardenedVerifyDir.
1698	*/
1699	DECLHIDDEN(int) supR3HardenedVerifyDir(const char *pszDirPath, bool fRecursive, bool fCheckFiles, PRTERRINFO pErrInfo)
1700	{
1701	/*
1702	* Validate the input path and parse it.
1703	*/
1704	SUPR3HARDENEDPATHINFO Info;
1705	int rc = supR3HardenedVerifyPathSanity(pszDirPath, pErrInfo, &Info);
1706	if (RT_FAILURE(rc))
1707	return rc;
1708
1709	/*
1710	* Verify each component from the root up.
1711	*/
1712	SUPR3HARDENEDFSOBJSTATE FsObjState;
1713	uint32_t const cComponents = Info.cComponents;
1714	for (uint32_t iComponent = 0; iComponent < cComponents; iComponent++)
1715	{
1716	bool fRelaxed = iComponent + 2 < cComponents;
1717	Info.szPath[Info.aoffComponents[iComponent + 1] - 1] = '\0';
1718	rc = supR3HardenedQueryFsObjectByPath(Info.szPath, &FsObjState, pErrInfo);
1719	if (RT_SUCCESS(rc))
1720	rc = supR3HardenedVerifyFsObject(&FsObjState, true /fDir/, fRelaxed,
1721	false /fSymlinksAllowed/, Info.szPath, pErrInfo);
1722	if (RT_FAILURE(rc))
1723	return rc;
1724	Info.szPath[Info.aoffComponents[iComponent + 1] - 1] = iComponent + 1 != cComponents ? RTPATH_SLASH : '\0';
1725	}
1726
1727	/*
1728	* Check files and subdirectories if requested.
1729	*/
1730	if (fCheckFiles \|\| fRecursive)
1731	{
1732	Info.szPath[Info.cch] = RTPATH_SLASH;
1733	Info.szPath[Info.cch + 1] = '\0';
1734	return supR3HardenedVerifyDirRecursive(Info.szPath, Info.cch + 1, &FsObjState,
1735	fRecursive, pErrInfo);
1736	}
1737
1738	return VINF_SUCCESS;
1739	}
1740
1741
1742	/**
1743	* Verfies a file.
1744	*
1745	* @returns VBox status code, error buffer filled on failure.
1746	* @param pszFilename The file to verify.
1747	* @param hNativeFile Handle to the file, verify that it's the same
1748	* as we ended up with when verifying the path.
1749	* RTHCUINTPTR_MAX means NIL here.
1750	* @param fMaybe3rdParty Set if the file is could be a supplied by a
1751	* third party. Different validation rules may
1752	* apply to 3rd party code on some platforms.
1753	* @param pErrInfo Where to return extended error information.
1754	* Optional.
1755	*/
1756	DECLHIDDEN(int) supR3HardenedVerifyFile(const char *pszFilename, RTHCUINTPTR hNativeFile,
1757	bool fMaybe3rdParty, PRTERRINFO pErrInfo)
1758	{
1759	/*
1760	* Validate the input path and parse it.
1761	*/
1762	SUPR3HARDENEDPATHINFO Info;
1763	int rc = supR3HardenedVerifyPathSanity(pszFilename, pErrInfo, &Info);
1764	if (RT_FAILURE(rc))
1765	return rc;
1766	if (Info.fDirSlash)
1767	return supR3HardenedSetError3(VERR_SUPLIB_IS_DIRECTORY, pErrInfo,
1768	"The file path specifies a directory: '", pszFilename, "'");
1769
1770	/*
1771	* Verify each component from the root up.
1772	*/
1773	SUPR3HARDENEDFSOBJSTATE FsObjState;
1774	uint32_t const cComponents = Info.cComponents;
1775	for (uint32_t iComponent = 0; iComponent < cComponents; iComponent++)
1776	{
1777	bool fFinal = iComponent + 1 == cComponents;
1778	bool fRelaxed = iComponent + 2 < cComponents;
1779	Info.szPath[Info.aoffComponents[iComponent + 1] - 1] = '\0';
1780	rc = supR3HardenedQueryFsObjectByPath(Info.szPath, &FsObjState, pErrInfo);
1781	if (RT_SUCCESS(rc))
1782	rc = supR3HardenedVerifyFsObject(&FsObjState, !fFinal /fDir/, fRelaxed,
1783	false /fSymlinksAllowed/, Info.szPath, pErrInfo);
1784	if (RT_FAILURE(rc))
1785	return rc;
1786	Info.szPath[Info.aoffComponents[iComponent + 1] - 1] = !fFinal ? RTPATH_SLASH : '\0';
1787	}
1788
1789	/*
1790	* Verify the file handle against the last component, if specified.
1791	*/
1792	if (hNativeFile != RTHCUINTPTR_MAX)
1793	{
1794	rc = supR3HardenedVerifySameFsObject(hNativeFile, &FsObjState, Info.szPath, pErrInfo);
1795	if (RT_FAILURE(rc))
1796	return rc;
1797	}
1798
1799	#ifdef RT_OS_WINDOWS
1800	/*
1801	* The files shall be signed on windows, verify that.
1802	*/
1803	rc = VINF_SUCCESS;
1804	HANDLE hVerify;
1805	if (hNativeFile == RTHCUINTPTR_MAX)
1806	{
1807	PRTUTF16 pwszPath;
1808	rc = RTStrToUtf16(pszFilename, &pwszPath);
1809	if (RT_SUCCESS(rc))
1810	{
1811	hVerify = CreateFileW(pwszPath, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
1812	RTUtf16Free(pwszPath);
1813	}
1814	else
1815	{
1816	rc = RTErrInfoSetF(pErrInfo, rc, "Error converting '%s' to UTF-16: %Rrc", pszFilename, rc);
1817	hVerify = INVALID_HANDLE_VALUE;
1818	}
1819	}
1820	else
1821	{
1822	NTSTATUS rcNt = NtDuplicateObject(NtCurrentProcess(), (HANDLE)hNativeFile, NtCurrentProcess(), &hVerify,
1823	GENERIC_READ, 0 /HandleAttributes/, 0 /Options/);
1824	if (!NT_SUCCESS(rcNt))
1825	hVerify = INVALID_HANDLE_VALUE;
1826	}
1827	if (hVerify != INVALID_HANDLE_VALUE)
1828	{
1829	# ifdef VBOX_WITH_HARDENING
1830	uint32_t fFlags = SUPHNTVI_F_REQUIRE_KERNEL_CODE_SIGNING;
1831	if (!fMaybe3rdParty)
1832	fFlags = SUPHNTVI_F_REQUIRE_BUILD_CERT;
1833	const char *pszSuffix = RTPathSuffix(pszFilename);
1834	if ( pszSuffix
1835	&& pszSuffix[0] == '.'
1836	&& ( RT_C_TO_LOWER(pszSuffix[1]) == 'r'
1837	\|\| RT_C_TO_LOWER(pszSuffix[1]) == 'g')
1838	&& RT_C_TO_LOWER(pszSuffix[2]) == 'c'
1839	&& pszSuffix[3] == '\0' )
1840	fFlags \|= SUPHNTVI_F_RC_IMAGE;
1841	# ifndef IN_SUP_R3_STATIC /* Not in VBoxCpuReport and friends. */
1842	rc = supHardenedWinVerifyImageByHandleNoName(hVerify, fFlags, pErrInfo);
1843	# endif
1844	# else
1845	RT_NOREF1(fMaybe3rdParty);
1846	# endif
1847	NtClose(hVerify);
1848	}
1849	else if (RT_SUCCESS(rc))
1850	rc = RTErrInfoSetF(pErrInfo, RTErrConvertFromWin32(RtlGetLastWin32Error()),
1851	"Error %u trying to open (or duplicate handle for) '%s'", RtlGetLastWin32Error(), pszFilename);
1852	if (RT_FAILURE(rc))
1853	return rc;
1854	#else
1855	RT_NOREF1(fMaybe3rdParty);
1856	#endif
1857
1858	return VINF_SUCCESS;
1859	}
1860
1861
1862	#if defined(RT_OS_DARWIN) \|\| defined(RT_OS_LINUX)
1863	/**
1864	* Verfies a file following symlinks.
1865	*
1866	* @returns VBox status code, error buffer filled on failure.
1867	* @param pszFilename The file to verify.
1868	* @param hNativeFile Handle to the file, verify that it's the same
1869	* as we ended up with when verifying the path.
1870	* RTHCUINTPTR_MAX means NIL here.
1871	* @param fMaybe3rdParty Set if the file is could be a supplied by a
1872	* third party. Different validation rules may
1873	* apply to 3rd party code on some platforms.
1874	* @param pErrInfo Where to return extended error information.
1875	* Optional.
1876	*
1877	* @note This is only used on OS X for libraries loaded with dlopen() because
1878	* the frameworks use symbolic links to point to the relevant library.
1879	*
1880	* @sa supR3HardenedVerifyFile
1881	*/
1882	DECLHIDDEN(int) supR3HardenedVerifyFileFollowSymlinks(const char *pszFilename, RTHCUINTPTR hNativeFile, bool fMaybe3rdParty,
1883	PRTERRINFO pErrInfo)
1884	{
1885	RT_NOREF1(fMaybe3rdParty);
1886
1887	/*
1888	* Validate the input path and parse it.
1889	*/
1890	SUPR3HARDENEDPATHINFO Info;
1891	int rc = supR3HardenedVerifyPathSanity(pszFilename, pErrInfo, &Info);
1892	if (RT_FAILURE(rc))
1893	return rc;
1894	if (Info.fDirSlash)
1895	return supR3HardenedSetError3(VERR_SUPLIB_IS_DIRECTORY, pErrInfo,
1896	"The file path specifies a directory: '", pszFilename, "'");
1897
1898	/*
1899	* Verify each component from the root up.
1900	*/
1901	#ifndef SUP_HARDENED_VERIFY_FOLLOW_SYMLINKS_USE_REALPATH
1902	uint32_t iLoops = 0;
1903	#endif
1904	SUPR3HARDENEDFSOBJSTATE FsObjState;
1905	uint32_t iComponent = 0;
1906	while (iComponent < Info.cComponents)
1907	{
1908	bool fFinal = iComponent + 1 == Info.cComponents;
1909	bool fRelaxed = iComponent + 2 < Info.cComponents;
1910	Info.szPath[Info.aoffComponents[iComponent + 1] - 1] = '\0';
1911	rc = supR3HardenedQueryFsObjectByPath(Info.szPath, &FsObjState, pErrInfo);
1912	if (RT_SUCCESS(rc))
1913	{
1914	/*
1915	* In case the component is a symlink expand it and start from the beginning after
1916	* verifying it has the proper access rights.
1917	* Furthermore only allow symlinks which don't contain any .. or . in the target
1918	* (enforced by supR3HardenedVerifyPathSanity).
1919	*/
1920	rc = supR3HardenedVerifyFsObject(&FsObjState, !fFinal /fDir/, fRelaxed,
1921	true /fSymlinksAllowed/, Info.szPath, pErrInfo);
1922	if ( RT_SUCCESS(rc)
1923	&& S_ISLNK(FsObjState.Stat.st_mode))
1924	{
1925	#if SUP_HARDENED_VERIFY_FOLLOW_SYMLINKS_USE_REALPATH /* Another approach using realpath() and verifying the result when encountering a symlink. */
1926	char *pszFilenameResolved = realpath(pszFilename, NULL);
1927	if (pszFilenameResolved)
1928	{
1929	rc = supR3HardenedVerifyFile(pszFilenameResolved, hNativeFile, fMaybe3rdParty, pErrInfo);
1930	free(pszFilenameResolved);
1931	return rc;
1932	}
1933	else
1934	{
1935	int iErr = errno;
1936	supR3HardenedError(VERR_ACCESS_DENIED, false /fFatal/,
1937	"supR3HardenedVerifyFileFollowSymlinks: Failed to resolve the real path '%s': %s (%d)\n",
1938	pszFilename, strerror(iErr), iErr);
1939	return supR3HardenedSetError4(VERR_ACCESS_DENIED, pErrInfo,
1940	"realpath failed for '", pszFilename, "': ", strerror(iErr));
1941	}
1942	#else
1943	/* Don't loop forever. */
1944	iLoops++;
1945	if (iLoops < 8)
1946	{
1947	/*
1948	* Construct new path by replacing the current component by the symlink value.
1949	* Note! readlink() is a weird API that doesn't necessarily indicates if the
1950	* buffer is too small.
1951	*/
1952	char szPath[RTPATH_MAX];
1953	size_t const cchBefore = Info.aoffComponents[iComponent]; /* includes slash */
1954	size_t const cchAfter = fFinal ? 0 : 1 /slash/ + Info.cch - Info.aoffComponents[iComponent + 1];
1955	if (sizeof(szPath) > cchBefore + cchAfter + 2)
1956	{
1957	ssize_t cchTarget = readlink(Info.szPath, szPath, sizeof(szPath) - 1);
1958	if (cchTarget > 0)
1959	{
1960	/* Some serious paranoia against embedded zero terminator and weird return values. */
1961	szPath[cchTarget] = '\0';
1962	size_t cchLink = strlen(szPath);
1963
1964	/* Strip trailing dirslashes of non-final link. */
1965	if (!fFinal)
1966	while (cchLink > 1 and szPath[cchLink - 1] == '/')
1967	cchLink--;
1968
1969	/* Check link value sanity and buffer size. */
1970	if (cchLink == 0)
1971	return supR3HardenedSetError3(VERR_ACCESS_DENIED, pErrInfo,
1972	"Bad readlink return for '", Info.szPath, "'");
1973	if (szPath[0] == '/')
1974	return supR3HardenedSetError3(VERR_ACCESS_DENIED, pErrInfo,
1975	"Absolute symbolic link not allowed: '", szPath, "'");
1976	if (cchBefore + cchLink + cchAfter + 1 /terminator/ > sizeof(szPath))
1977	return supR3HardenedSetError(VERR_SUPLIB_PATH_TOO_LONG, pErrInfo,
1978	"Symlinks causing too long path!");
1979
1980	/* Construct the new path. */
1981	if (cchBefore)
1982	memmove(&szPath[cchBefore], &szPath[0], cchLink);
1983	memcpy(&szPath[0], Info.szPath, cchBefore);
1984	if (!cchAfter)
1985	szPath[cchBefore + cchLink] = '\0';
1986	else
1987	{
1988	szPath[cchBefore + cchLink] = RTPATH_SLASH;
1989	memcpy(&szPath[cchBefore + cchLink + 1],
1990	&Info.szPath[Info.aoffComponents[iComponent + 1]],
1991	cchAfter); /* cchAfter includes a zero terminator */
1992	}
1993
1994	/* Parse, copy and check the sanity (no '..' or '.') of the altered path. */
1995	rc = supR3HardenedVerifyPathSanity(szPath, pErrInfo, &Info);
1996	if (RT_FAILURE(rc))
1997	return rc;
1998	if (Info.fDirSlash)
1999	return supR3HardenedSetError3(VERR_SUPLIB_IS_DIRECTORY, pErrInfo,
2000	"The file path specifies a directory: '", szPath, "'");
2001
2002	/* Restart from the current component. */
2003	continue;
2004	}
2005	int iErr = errno;
2006	supR3HardenedError(VERR_ACCESS_DENIED, false /fFatal/,
2007	"supR3HardenedVerifyFileFollowSymlinks: Failed to readlink '%s': %s (%d)\n",
2008	Info.szPath, strerror(iErr), iErr);
2009	return supR3HardenedSetError4(VERR_ACCESS_DENIED, pErrInfo,
2010	"readlink failed for '", Info.szPath, "': ", strerror(iErr));
2011	}
2012	return supR3HardenedSetError(VERR_SUPLIB_PATH_TOO_LONG, pErrInfo, "Path too long for symlink replacing!");
2013	}
2014	else
2015	return supR3HardenedSetError3(VERR_TOO_MANY_SYMLINKS, pErrInfo,
2016	"Too many symbolic links: '", pszFilename, "'");
2017	#endif
2018	}
2019	}
2020	if (RT_FAILURE(rc))
2021	return rc;
2022	Info.szPath[Info.aoffComponents[iComponent + 1] - 1] = !fFinal ? RTPATH_SLASH : '\0';
2023	iComponent++;
2024	}
2025
2026	/*
2027	* Verify the file handle against the last component, if specified.
2028	*/
2029	if (hNativeFile != RTHCUINTPTR_MAX)
2030	{
2031	rc = supR3HardenedVerifySameFsObject(hNativeFile, &FsObjState, Info.szPath, pErrInfo);
2032	if (RT_FAILURE(rc))
2033	return rc;
2034	}
2035
2036	return VINF_SUCCESS;
2037	}
2038	#endif /* RT_OS_DARWIN \|\| RT_OS_LINUX */
2039
2040
2041	/**
2042	* Gets the pre-init data for the hand-over to the other version
2043	* of this code.
2044	*
2045	* The reason why we pass this information on is that it contains
2046	* open directories and files. Later it may include even more info
2047	* (int the verified arrays mostly).
2048	*
2049	* The receiver is supR3HardenedRecvPreInitData.
2050	*
2051	* @param pPreInitData Where to store it.
2052	*/
2053	DECLHIDDEN(void) supR3HardenedGetPreInitData(PSUPPREINITDATA pPreInitData)
2054	{
2055	pPreInitData->cInstallFiles = RT_ELEMENTS(g_aSupInstallFiles);
2056	pPreInitData->paInstallFiles = &g_aSupInstallFiles[0];
2057	pPreInitData->paVerifiedFiles = &g_aSupVerifiedFiles[0];
2058
2059	pPreInitData->cVerifiedDirs = RT_ELEMENTS(g_aSupVerifiedDirs);
2060	pPreInitData->paVerifiedDirs = &g_aSupVerifiedDirs[0];
2061	}
2062
2063
2064	/**
2065	* Receives the pre-init data from the static executable stub.
2066	*
2067	* @returns VBox status code. Will not bitch on failure since the
2068	* runtime isn't ready for it, so that is left to the exe stub.
2069	*
2070	* @param pPreInitData The hand-over data.
2071	*/
2072	DECLHIDDEN(int) supR3HardenedRecvPreInitData(PCSUPPREINITDATA pPreInitData)
2073	{
2074	/*
2075	* Compare the array lengths and the contents of g_aSupInstallFiles.
2076	*/
2077	if ( pPreInitData->cInstallFiles != RT_ELEMENTS(g_aSupInstallFiles)
2078	\|\| pPreInitData->cVerifiedDirs != RT_ELEMENTS(g_aSupVerifiedDirs))
2079	return VERR_VERSION_MISMATCH;
2080	SUPINSTFILE const *paInstallFiles = pPreInitData->paInstallFiles;
2081	for (unsigned iFile = 0; iFile < RT_ELEMENTS(g_aSupInstallFiles); iFile++)
2082	if ( g_aSupInstallFiles[iFile].enmDir != paInstallFiles[iFile].enmDir
2083	\|\| g_aSupInstallFiles[iFile].enmType != paInstallFiles[iFile].enmType
2084	\|\| g_aSupInstallFiles[iFile].fOptional != paInstallFiles[iFile].fOptional
2085	\|\| suplibHardenedStrCmp(g_aSupInstallFiles[iFile].pszFile, paInstallFiles[iFile].pszFile))
2086	return VERR_VERSION_MISMATCH;
2087
2088	/*
2089	* Check that we're not called out of order.
2090	* If dynamic linking it screwed up, we may end up here.
2091	*/
2092	if ( !ASMMemIsZero(&g_aSupVerifiedFiles[0], sizeof(g_aSupVerifiedFiles))
2093	\|\| !ASMMemIsZero(&g_aSupVerifiedDirs[0], sizeof(g_aSupVerifiedDirs)))
2094	return VERR_WRONG_ORDER;
2095
2096	/*
2097	* Copy the verification data over.
2098	*/
2099	suplibHardenedMemCopy(&g_aSupVerifiedFiles[0], pPreInitData->paVerifiedFiles, sizeof(g_aSupVerifiedFiles));
2100	suplibHardenedMemCopy(&g_aSupVerifiedDirs[0], pPreInitData->paVerifiedDirs, sizeof(g_aSupVerifiedDirs));
2101	return VINF_SUCCESS;
2102	}

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source: vbox/trunk/src/VBox/HostDrivers/Support/SUPR3HardenedVerify.cpp@ 68033

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