| /* | |
| * Copyright (c) 2004, 2022, Oracle and/or its affiliates. All rights reserved. | |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. | |
| * | |
| * This code is free software; you can redistribute it and/or modify it | |
| * under the terms of the GNU General Public License version 2 only, as | |
| * published by the Free Software Foundation. Oracle designates this | |
| * particular file as subject to the "Classpath" exception as provided | |
| * by Oracle in the LICENSE file that accompanied this code. | |
| * | |
| * This code 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 | |
| * version 2 for more details (a copy is included in the LICENSE file that | |
| * accompanied this code). | |
| * | |
| * You should have received a copy of the GNU General Public License version | |
| * 2 along with this work; if not, write to the Free Software Foundation, | |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | |
| * | |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA | |
| * or visit www.oracle.com if you need additional information or have any | |
| * questions. | |
| */ | |
| #include <windows.h> | |
| #include <malloc.h> | |
| #include <string.h> | |
| #include "jni.h" | |
| #include "jni_util.h" | |
| #include "jdk_internal_agent_FileSystemImpl.h" | |
| JNIEXPORT jint JNICALL DEF_JNI_OnLoad(JavaVM *vm, void *reserved) | |
| { | |
| JNIEnv* env; | |
| if ((*vm)->GetEnv(vm, (void**) &env, JNI_VERSION_1_2) != JNI_OK) { | |
| return JNI_EVERSION; /* JNI version not supported */ | |
| } | |
| return JNI_VERSION_19; | |
| } | |
| /* | |
| * Access mask to represent any file access | |
| */ | |
| #define ANY_ACCESS (FILE_GENERIC_READ | FILE_GENERIC_WRITE | FILE_GENERIC_EXECUTE) | |
| /* | |
| * Returns JNI_TRUE if the specified file is on a file system that supports | |
| * persistent ACLs (On NTFS file systems returns true, on FAT32 file systems | |
| * returns false). | |
| */ | |
| static jboolean isSecuritySupported(JNIEnv* env, const char* path) { | |
| char* root; | |
| char* p; | |
| BOOL res; | |
| DWORD dwMaxComponentLength; | |
| DWORD dwFlags; | |
| char fsName[128]; | |
| DWORD fsNameLength; | |
| /* | |
| * Get root directory. Assume that files are absolute paths. For UNCs | |
| * the slash after the share name is required. | |
| */ | |
| root = strdup(path); | |
| if (*root == '\\') { | |
| /* | |
| * \\server\share\file ==> \\server\share\ | |
| */ | |
| int slashskip = 3; | |
| p = root; | |
| while ((*p == '\\') && (slashskip > 0)) { | |
| char* p2; | |
| p++; | |
| p2 = strchr(p, '\\'); | |
| if ((p2 == NULL) || (*p2 != '\\')) { | |
| free(root); | |
| JNU_ThrowIOException(env, "Malformed UNC"); | |
| return JNI_FALSE; | |
| } | |
| p = p2; | |
| slashskip--; | |
| } | |
| if (slashskip != 0) { | |
| free(root); | |
| JNU_ThrowIOException(env, "Malformed UNC"); | |
| return JNI_FALSE; | |
| } | |
| p++; | |
| *p = '\0'; | |
| } else { | |
| p = strchr(root, '\\'); | |
| if (p == NULL) { | |
| free(root); | |
| JNU_ThrowIOException(env, "Absolute filename not specified"); | |
| return JNI_FALSE; | |
| } | |
| p++; | |
| *p = '\0'; | |
| } | |
| /* | |
| * Get the volume information - this gives us the file system file and | |
| * also tells us if the file system supports persistent ACLs. | |
| */ | |
| fsNameLength = sizeof(fsName)-1; | |
| res = GetVolumeInformation(root, | |
| NULL, // address of name of the volume, can be NULL | |
| 0, // length of volume name | |
| NULL, // address of volume serial number, can be NULL | |
| &dwMaxComponentLength, | |
| &dwFlags, | |
| fsName, | |
| fsNameLength); | |
| if (res == 0) { | |
| free(root); | |
| JNU_ThrowIOExceptionWithLastError(env, "GetVolumeInformation failed"); | |
| return JNI_FALSE; | |
| } | |
| free(root); | |
| return (dwFlags & FS_PERSISTENT_ACLS) ? JNI_TRUE : JNI_FALSE; | |
| } | |
| /* | |
| * Returns the security descriptor for a file. | |
| */ | |
| static SECURITY_DESCRIPTOR* getFileSecurityDescriptor(JNIEnv* env, const char* path) { | |
| SECURITY_DESCRIPTOR* sd; | |
| DWORD len = 0; | |
| SECURITY_INFORMATION info = | |
| OWNER_SECURITY_INFORMATION | DACL_SECURITY_INFORMATION; | |
| GetFileSecurityA(path, info , 0, 0, &len); | |
| if (GetLastError() != ERROR_INSUFFICIENT_BUFFER) { | |
| JNU_ThrowIOExceptionWithLastError(env, "GetFileSecurity failed"); | |
| return NULL; | |
| } | |
| sd = (SECURITY_DESCRIPTOR *)malloc(len); | |
| if (sd == NULL) { | |
| JNU_ThrowOutOfMemoryError(env, 0); | |
| } else { | |
| if (!(*GetFileSecurityA)(path, info, sd, len, &len)) { | |
| JNU_ThrowIOExceptionWithLastError(env, "GetFileSecurity failed"); | |
| free(sd); | |
| return NULL; | |
| } | |
| } | |
| return sd; | |
| } | |
| /* | |
| * Returns pointer to the SID identifying the owner of the specified | |
| * file. | |
| */ | |
| static SID* getFileOwner(JNIEnv* env, SECURITY_DESCRIPTOR* sd) { | |
| SID* owner; | |
| BOOL defaulted; | |
| if (!GetSecurityDescriptorOwner(sd, &owner, &defaulted)) { | |
| JNU_ThrowIOExceptionWithLastError(env, "GetSecurityDescriptorOwner failed"); | |
| return NULL; | |
| } | |
| return owner; | |
| } | |
| /* | |
| * Returns pointer discretionary access-control list (ACL) from the security | |
| * descriptor of the specified file. | |
| */ | |
| static ACL* getFileDACL(JNIEnv* env, SECURITY_DESCRIPTOR* sd) { | |
| ACL *acl; | |
| int defaulted, present; | |
| if (!GetSecurityDescriptorDacl(sd, &present, &acl, &defaulted)) { | |
| JNU_ThrowIOExceptionWithLastError(env, "GetSecurityDescriptorDacl failed"); | |
| return NULL; | |
| } | |
| if (!present) { | |
| JNU_ThrowInternalError(env, "Security descriptor does not contain a DACL"); | |
| return NULL; | |
| } | |
| return acl; | |
| } | |
| /* | |
| * Returns JNI_TRUE if the specified owner is the only SID will access | |
| * to the file. | |
| */ | |
| static jboolean isAccessUserOnly(JNIEnv* env, SID* owner, ACL* acl) { | |
| ACL_SIZE_INFORMATION acl_size_info; | |
| DWORD i; | |
| /* | |
| * If there's no DACL then there's no access to the file | |
| */ | |
| if (acl == NULL) { | |
| return JNI_TRUE; | |
| } | |
| /* | |
| * Get the ACE count | |
| */ | |
| if (!GetAclInformation(acl, (void *) &acl_size_info, sizeof(acl_size_info), | |
| AclSizeInformation)) { | |
| JNU_ThrowIOExceptionWithLastError(env, "GetAclInformation failed"); | |
| return JNI_FALSE; | |
| } | |
| /* | |
| * Iterate over the ACEs. For each "allow" type check that the SID | |
| * matches the owner, and check that the access is read only. | |
| */ | |
| for (i = 0; i < acl_size_info.AceCount; i++) { | |
| void* ace; | |
| ACCESS_ALLOWED_ACE *access; | |
| SID* sid; | |
| if (!GetAce(acl, i, &ace)) { | |
| JNU_ThrowIOExceptionWithLastError(env, "GetAce failed"); | |
| return -1; | |
| } | |
| if (((ACCESS_ALLOWED_ACE *)ace)->Header.AceType != ACCESS_ALLOWED_ACE_TYPE) { | |
| continue; | |
| } | |
| access = (ACCESS_ALLOWED_ACE *)ace; | |
| sid = (SID *) &access->SidStart; | |
| if (!EqualSid(owner, sid)) { | |
| /* | |
| * If the ACE allows any access then the file is not secure. | |
| */ | |
| if (access->Mask & ANY_ACCESS) { | |
| return JNI_FALSE; | |
| } | |
| } | |
| } | |
| return JNI_TRUE; | |
| } | |
| /* | |
| * Class: jdk_internal_agent_FileSystemImpl | |
| * Method: init0 | |
| * Signature: ()V | |
| */ | |
| JNIEXPORT void JNICALL Java_jdk_internal_agent_FileSystemImpl_init0 | |
| (JNIEnv *env, jclass ignored) | |
| { | |
| /* nothing to do */ | |
| } | |
| /* | |
| * Class: jdk_internal_agent_FileSystemImpl | |
| * Method: isSecuritySupported0 | |
| * Signature: (Ljava/lang/String;)Z | |
| */ | |
| JNIEXPORT jboolean JNICALL Java_jdk_internal_agent_FileSystemImpl_isSecuritySupported0 | |
| (JNIEnv *env, jclass ignored, jstring str) | |
| { | |
| jboolean res; | |
| jboolean isCopy; | |
| const char* path; | |
| path = JNU_GetStringPlatformChars(env, str, &isCopy); | |
| if (path != NULL) { | |
| res = isSecuritySupported(env, path); | |
| if (isCopy) { | |
| JNU_ReleaseStringPlatformChars(env, str, path); | |
| } | |
| return res; | |
| } else { | |
| /* exception thrown - doesn't matter what we return */ | |
| return JNI_TRUE; | |
| } | |
| } | |
| /* | |
| * Class: jdk_internal_agent_FileSystemImpl | |
| * Method: isAccessUserOnly0 | |
| * Signature: (Ljava/lang/String;)Z | |
| */ | |
| JNIEXPORT jboolean JNICALL Java_jdk_internal_agent_FileSystemImpl_isAccessUserOnly0 | |
| (JNIEnv *env, jclass ignored, jstring str) | |
| { | |
| jboolean res = JNI_FALSE; | |
| jboolean isCopy; | |
| const char* path; | |
| path = JNU_GetStringPlatformChars(env, str, &isCopy); | |
| if (path != NULL) { | |
| /* | |
| * From the security descriptor get the file owner and | |
| * DACL. Then check if anybody but the owner has access | |
| * to the file. | |
| */ | |
| SECURITY_DESCRIPTOR* sd = getFileSecurityDescriptor(env, path); | |
| if (sd != NULL) { | |
| SID *owner = getFileOwner(env, sd); | |
| if (owner != NULL) { | |
| ACL* acl = getFileDACL(env, sd); | |
| if (acl != NULL) { | |
| res = isAccessUserOnly(env, owner, acl); | |
| } else { | |
| /* | |
| * If acl is NULL it means that an exception was thrown | |
| * or there is "all access" to the file. | |
| */ | |
| res = JNI_FALSE; | |
| } | |
| } | |
| free(sd); | |
| } | |
| if (isCopy) { | |
| JNU_ReleaseStringPlatformChars(env, str, path); | |
| } | |
| } | |
| return res; | |
| } |