1 /* 2 * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 /* Need to define this to get CAPI functions included */ 27 #ifndef _WIN32_WINNT 28 #define _WIN32_WINNT 0x0400 29 #endif 30 31 #include <windows.h> 32 #include <wincrypt.h> 33 #include <jni.h> 34 #include "sun_security_provider_NativeSeedGenerator.h" 35 36 /* 37 * Get a random seed from the MS CryptoAPI. Return true if successful, false 38 * otherwise. 39 * 40 * Some early versions of Windows 95 do not support the required functions. 41 * Use runtime linking to avoid problems. 42 * 43 */ 44 JNIEXPORT jboolean JNICALL Java_sun_security_provider_NativeSeedGenerator_nativeGenerateSeed 45 (JNIEnv *env, jclass clazz, jbyteArray randArray) 46 { 47 HCRYPTPROV hCryptProv; 48 jboolean result = JNI_FALSE; 49 jsize numBytes; 50 jbyte* randBytes; 51 52 if (CryptAcquireContextA(&hCryptProv, "J2SE", NULL, PROV_RSA_FULL, 0) == FALSE) { 53 /* If CSP context hasn't been created, create one. */ 54 if (CryptAcquireContextA(&hCryptProv, "J2SE", NULL, PROV_RSA_FULL, 55 CRYPT_NEWKEYSET) == FALSE) { 56 return result; 57 } 58 } 59 60 numBytes = (*env)->GetArrayLength(env, randArray); 61 randBytes = (*env)->GetByteArrayElements(env, randArray, NULL); 62 if (CryptGenRandom(hCryptProv, numBytes, randBytes)) { 63 result = JNI_TRUE; 64 } 65 (*env)->ReleaseByteArrayElements(env, randArray, randBytes, 0); 66 67 CryptReleaseContext(hCryptProv, 0); 68 69 return result; 70 }