/*

 * Copyright (c) 2011, 2015, 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.

 */

#import "sun_security_krb5_Credentials.h"

#import <Kerberos/Kerberos.h>

#import <string.h>

#import <time.h>

#include "jni_util.h"

/*

 * Based largely on klist.c,

 *

 * Created by Scott Kovatch on 8/12/04.

 *

 * See http://www.opensource.apple.com/darwinsource/10.3.3/Kerberos-47/KerberosClients/klist/Sources/klist.c

 */

/*

 * Statics for this module

 */

static jclass derValueClass = NULL;

static jclass ticketClass = NULL;

static jclass principalNameClass = NULL;

static jclass encryptionKeyClass = NULL;

static jclass ticketFlagsClass = NULL;

static jclass kerberosTimeClass = NULL;

static jclass javaLangStringClass = NULL;

static jclass javaLangIntegerClass = NULL;

static jclass hostAddressClass = NULL;

static jclass hostAddressesClass = NULL;

static jmethodID derValueConstructor = 0;

static jmethodID ticketConstructor = 0;

static jmethodID principalNameConstructor = 0;

static jmethodID encryptionKeyConstructor = 0;

static jmethodID ticketFlagsConstructor = 0;

static jmethodID kerberosTimeConstructor = 0;

static jmethodID krbcredsConstructor = 0;

static jmethodID integerConstructor = 0;

static jmethodID hostAddressConstructor = 0;

static jmethodID hostAddressesConstructor = 0;

/*

 * Function prototypes for internal routines

 */

static jobject BuildTicket(JNIEnv *env, krb5_data *encodedTicket);

static jobject BuildClientPrincipal(JNIEnv *env, krb5_context kcontext, krb5_principal principalName);

static jobject BuildEncryptionKey(JNIEnv *env, krb5_keyblock *cryptoKey);

static jobject BuildTicketFlags(JNIEnv *env, krb5_flags flags);

static jobject BuildKerberosTime(JNIEnv *env, krb5_timestamp kerbtime);

static jobject BuildAddressList(JNIEnv *env, krb5_address **kerbtime);

static void printiferr (errcode_t err, const char *format, ...);

static jclass FindClass(JNIEnv *env, char *className)

{

    jclass cls = (*env)->FindClass(env, className);

    if (cls == NULL) {

        printf("Couldn't find %s\n", className);

        return NULL;

    }

    jobject returnValue = (*env)->NewWeakGlobalRef(env,cls);

    return returnValue;

}

/*

 * Class:     sun_security_krb5_KrbCreds

 * Method:    JNI_OnLoad

 */

JNIEXPORT jint JNICALL DEF_JNI_OnLoad(JavaVM *jvm, void *reserved)

{

    JNIEnv *env;

    if ((*jvm)->GetEnv(jvm, (void **)&env, JNI_VERSION_1_4)) {

        return JNI_EVERSION; /* JNI version not supported */

    }

    ticketClass = FindClass(env, "sun/security/krb5/internal/Ticket");

    if (ticketClass == NULL) return JNI_ERR;

    principalNameClass = FindClass(env, "sun/security/krb5/PrincipalName");

    if (principalNameClass == NULL) return JNI_ERR;

    derValueClass = FindClass(env, "sun/security/util/DerValue");

    if (derValueClass == NULL) return JNI_ERR;

    encryptionKeyClass = FindClass(env, "sun/security/krb5/EncryptionKey");

    if (encryptionKeyClass == NULL) return JNI_ERR;

    ticketFlagsClass = FindClass(env,"sun/security/krb5/internal/TicketFlags");

    if (ticketFlagsClass == NULL) return JNI_ERR;

    kerberosTimeClass = FindClass(env,"sun/security/krb5/internal/KerberosTime");

    if (kerberosTimeClass == NULL) return JNI_ERR;

    javaLangStringClass = FindClass(env,"java/lang/String");

    if (javaLangStringClass == NULL) return JNI_ERR;

    javaLangIntegerClass = FindClass(env,"java/lang/Integer");

    if (javaLangIntegerClass == NULL) return JNI_ERR;

    hostAddressClass = FindClass(env,"sun/security/krb5/internal/HostAddress");

    if (hostAddressClass == NULL) return JNI_ERR;

    hostAddressesClass = FindClass(env,"sun/security/krb5/internal/HostAddresses");

    if (hostAddressesClass == NULL) return JNI_ERR;

    derValueConstructor = (*env)->GetMethodID(env, derValueClass, "<init>", "([B)V");

    if (derValueConstructor == 0) {

        printf("Couldn't find DerValue constructor\n");

        return JNI_ERR;

    }

    ticketConstructor = (*env)->GetMethodID(env, ticketClass, "<init>", "(Lsun/security/util/DerValue;)V");

    if (ticketConstructor == 0) {

        printf("Couldn't find Ticket constructor\n");

        return JNI_ERR;

    }

    principalNameConstructor = (*env)->GetMethodID(env, principalNameClass, "<init>", "(Ljava/lang/String;I)V");

    if (principalNameConstructor == 0) {

        printf("Couldn't find PrincipalName constructor\n");

        return JNI_ERR;

    }

    encryptionKeyConstructor = (*env)->GetMethodID(env, encryptionKeyClass, "<init>", "(I[B)V");

    if (encryptionKeyConstructor == 0) {

        printf("Couldn't find EncryptionKey constructor\n");

        return JNI_ERR;

    }

    ticketFlagsConstructor = (*env)->GetMethodID(env, ticketFlagsClass, "<init>", "(I[B)V");

    if (ticketFlagsConstructor == 0) {

        printf("Couldn't find TicketFlags constructor\n");

        return JNI_ERR;

    }

    kerberosTimeConstructor = (*env)->GetMethodID(env, kerberosTimeClass, "<init>", "(J)V");

    if (kerberosTimeConstructor == 0) {

        printf("Couldn't find KerberosTime constructor\n");

        return JNI_ERR;

    }

    integerConstructor = (*env)->GetMethodID(env, javaLangIntegerClass, "<init>", "(I)V");

    if (integerConstructor == 0) {

        printf("Couldn't find Integer constructor\n");

        return JNI_ERR;

    }

    hostAddressConstructor = (*env)->GetMethodID(env, hostAddressClass, "<init>", "(I[B)V");

    if (hostAddressConstructor == 0) {

        printf("Couldn't find HostAddress constructor\n");

        return JNI_ERR;

    }

    hostAddressesConstructor = (*env)->GetMethodID(env, hostAddressesClass, "<init>", "([Lsun/security/krb5/internal/HostAddress;)V");

    if (hostAddressesConstructor == 0) {

        printf("Couldn't find HostAddresses constructor\n");

        return JNI_ERR;

    }

    return JNI_VERSION_1_2;

}

/*

 * Class:     sun_security_jgss_KrbCreds

 * Method:    JNI_OnUnload

 */

JNIEXPORT void JNICALL DEF_JNI_OnUnload(JavaVM *jvm, void *reserved)

{

    JNIEnv *env;

    if ((*jvm)->GetEnv(jvm, (void **)&env, JNI_VERSION_1_2)) {

        return; /* Nothing else we can do */

    }

    if (ticketClass != NULL) {

        (*env)->DeleteWeakGlobalRef(env,ticketClass);

    }

    if (derValueClass != NULL) {

        (*env)->DeleteWeakGlobalRef(env,derValueClass);

    }

    if (principalNameClass != NULL) {

        (*env)->DeleteWeakGlobalRef(env,principalNameClass);

    }

    if (encryptionKeyClass != NULL) {

        (*env)->DeleteWeakGlobalRef(env,encryptionKeyClass);

    }

    if (ticketFlagsClass != NULL) {

        (*env)->DeleteWeakGlobalRef(env,ticketFlagsClass);

    }

    if (kerberosTimeClass != NULL) {

        (*env)->DeleteWeakGlobalRef(env,kerberosTimeClass);

    }

    if (javaLangStringClass != NULL) {

        (*env)->DeleteWeakGlobalRef(env,javaLangStringClass);

    }

    if (javaLangIntegerClass != NULL) {

        (*env)->DeleteWeakGlobalRef(env,javaLangIntegerClass);

    }

    if (hostAddressClass != NULL) {

        (*env)->DeleteWeakGlobalRef(env,hostAddressClass);

    }

    if (hostAddressesClass != NULL) {

        (*env)->DeleteWeakGlobalRef(env,hostAddressesClass);

    }

}

int isIn(krb5_enctype e, int n, jint* etypes)

{

    int i;

    for (i=0; i<n; i++) {

        if (e == etypes[i]) return 1;

    }

    return 0;

}

/*

 * Class:     sun_security_krb5_Credentials

 * Method:    acquireDefaultNativeCreds

 * Signature: ([I])Lsun/security/krb5/Credentials;

 */

JNIEXPORT jobject JNICALL Java_sun_security_krb5_Credentials_acquireDefaultNativeCreds

(JNIEnv *env, jclass krbcredsClass, jintArray jetypes)

{

    jobject krbCreds = NULL;

    krb5_error_code err = 0;

    krb5_ccache ccache = NULL;

    krb5_cc_cursor cursor = NULL;

    krb5_creds creds;

    krb5_flags flags = 0;

    krb5_context kcontext = NULL;

    int netypes;

    jint *etypes = NULL;

    /* Initialize the Kerberos 5 context */

    err = krb5_init_context (&kcontext);

    if (!err) {

        err = krb5_cc_default (kcontext, &ccache);

    }

    if (!err) {

        err = krb5_cc_set_flags (kcontext, ccache, flags); /* turn off OPENCLOSE */

    }

    if (!err) {

        err = krb5_cc_start_seq_get (kcontext, ccache, &cursor);

    }

    netypes = (*env)->GetArrayLength(env, jetypes);

    etypes = (jint *) (*env)->GetIntArrayElements(env, jetypes, NULL);

    if (etypes != NULL && !err) {

        while ((err = krb5_cc_next_cred (kcontext, ccache, &cursor, &creds)) == 0) {

            char *serverName = NULL;

            if (!err) {

                err = krb5_unparse_name (kcontext, creds.server, &serverName);

                printiferr (err, "while unparsing server name");

            }

            if (!err) {

                char* slash = strchr(serverName, '/');

                char* at = strchr(serverName, '@');

                // Make sure the server's name is krbtgt/REALM@REALM, the etype

                // is supported, and the ticket has not expired

                if (slash && at &&

                        strncmp (serverName, "krbtgt", slash-serverName) == 0 &&

                            // the ablove line shows at must be after slash

                        strncmp (slash+1, at+1, at-slash-1) == 0 &&

                        isIn (creds.keyblock.enctype, netypes, etypes) &&

                        creds.times.endtime > time(0)) {

                    jobject ticket, clientPrincipal, targetPrincipal, encryptionKey;

                    jobject ticketFlags, startTime, endTime;

                    jobject authTime, renewTillTime, hostAddresses;

                    ticket = clientPrincipal = targetPrincipal = encryptionKey = NULL;

                    ticketFlags = startTime = endTime = NULL;

                    authTime = renewTillTime = hostAddresses = NULL;

                    // For the default credentials we're only interested in the krbtgt server.

                    clientPrincipal = BuildClientPrincipal(env, kcontext, creds.client);

                    if (clientPrincipal == NULL) goto cleanup;

                    targetPrincipal = BuildClientPrincipal(env, kcontext, creds.server);

                    if (targetPrincipal == NULL) goto cleanup;

                    // Build a sun/security/krb5/internal/Ticket

                    ticket = BuildTicket(env, &creds.ticket);

                    if (ticket == NULL) goto cleanup;

                    // Get the encryption key

                    encryptionKey = BuildEncryptionKey(env, &creds.keyblock);

                    if (encryptionKey == NULL) goto cleanup;

                    // and the ticket flags

                    ticketFlags = BuildTicketFlags(env, creds.ticket_flags);

                    if (ticketFlags == NULL) goto cleanup;

                    // Get the timestamps out.

                    startTime = BuildKerberosTime(env, creds.times.starttime);

                    if (startTime == NULL) goto cleanup;

                    authTime = BuildKerberosTime(env, creds.times.authtime);

                    if (authTime == NULL) goto cleanup;

                    endTime = BuildKerberosTime(env, creds.times.endtime);

                    if (endTime == NULL) goto cleanup;

                    renewTillTime = BuildKerberosTime(env, creds.times.renew_till);

                    if (renewTillTime == NULL) goto cleanup;

                    // Create the addresses object.

                    hostAddresses = BuildAddressList(env, creds.addresses);

                    if (krbcredsConstructor == 0) {

                        krbcredsConstructor = (*env)->GetMethodID(env, krbcredsClass, "<init>",

                                                                  "(Lsun/security/krb5/internal/Ticket;Lsun/security/krb5/PrincipalName;Lsun/security/krb5/PrincipalName;Lsun/security/krb5/EncryptionKey;Lsun/security/krb5/internal/TicketFlags;Lsun/security/krb5/internal/KerberosTime;Lsun/security/krb5/internal/KerberosTime;Lsun/security/krb5/internal/KerberosTime;Lsun/security/krb5/internal/KerberosTime;Lsun/security/krb5/internal/HostAddresses;)V");

                        if (krbcredsConstructor == 0) {

                            printf("Couldn't find sun.security.krb5.internal.Ticket constructor\n");

                            break;

                        }

                    }

                    // and now go build a KrbCreds object

                    krbCreds = (*env)->NewObject(

                                                 env,

                                                 krbcredsClass,

                                                 krbcredsConstructor,

                                                 ticket,

                                                 clientPrincipal,

                                                 targetPrincipal,

                                                 encryptionKey,

                                                 ticketFlags,

                                                 authTime,

                                                 startTime,

                                                 endTime,

                                                 renewTillTime,

                                                 hostAddresses);

cleanup:

                    if (ticket) (*env)->DeleteLocalRef(env, ticket);

                    if (clientPrincipal) (*env)->DeleteLocalRef(env, clientPrincipal);

                    if (targetPrincipal) (*env)->DeleteLocalRef(env, targetPrincipal);

                    if (encryptionKey) (*env)->DeleteLocalRef(env, encryptionKey);

                    if (ticketFlags) (*env)->DeleteLocalRef(env, ticketFlags);

                    if (authTime) (*env)->DeleteLocalRef(env, authTime);

                    if (startTime) (*env)->DeleteLocalRef(env, startTime);

                    if (endTime) (*env)->DeleteLocalRef(env, endTime);

                    if (renewTillTime) (*env)->DeleteLocalRef(env, renewTillTime);

                    if (hostAddresses) (*env)->DeleteLocalRef(env, hostAddresses);

                    // Stop if there is an exception or we already found the initial TGT

                    if ((*env)->ExceptionCheck(env) || krbCreds) {

                        break;

                    }

                }

            }

            if (serverName != NULL) { krb5_free_unparsed_name (kcontext, serverName); }

            krb5_free_cred_contents (kcontext, &creds);

        }

        if (err == KRB5_CC_END) { err = 0; }

        printiferr (err, "while retrieving a ticket");

    }

    if (!err) {

        err = krb5_cc_end_seq_get (kcontext, ccache, &cursor);

        printiferr (err, "while finishing ticket retrieval");

    }

    if (!err) {

        flags = KRB5_TC_OPENCLOSE; /* restore OPENCLOSE mode */

        err = krb5_cc_set_flags (kcontext, ccache, flags);

        printiferr (err, "while finishing ticket retrieval");

    }

    if (etypes != NULL) {

        (*env)->ReleaseIntArrayElements(env, jetypes, etypes, 0);

    }

    krb5_free_context (kcontext);

    return krbCreds;

}

#pragma mark -

jobject BuildTicket(JNIEnv *env, krb5_data *encodedTicket)

{

    /* To build a Ticket, we first need to build a DerValue out of the EncodedTicket.

    * But before we can do that, we need to make a byte array out of the ET.

    */

    jobject derValue, ticket;

    jbyteArray ary;

    ary = (*env)->NewByteArray(env, encodedTicket->length);

    if ((*env)->ExceptionCheck(env)) {

        return (jobject) NULL;

    }

    (*env)->SetByteArrayRegion(env, ary, (jsize) 0, encodedTicket->length, (jbyte *)encodedTicket->data);

    if ((*env)->ExceptionCheck(env)) {

        (*env)->DeleteLocalRef(env, ary);

        return (jobject) NULL;

    }

    derValue = (*env)->NewObject(env, derValueClass, derValueConstructor, ary);

    if ((*env)->ExceptionCheck(env)) {

        (*env)->DeleteLocalRef(env, ary);

        return (jobject) NULL;

    }

    (*env)->DeleteLocalRef(env, ary);

    ticket = (*env)->NewObject(env, ticketClass, ticketConstructor, derValue);

    if ((*env)->ExceptionCheck(env)) {

        (*env)->DeleteLocalRef(env, derValue);

        return (jobject) NULL;

    }

    (*env)->DeleteLocalRef(env, derValue);

    return ticket;

}

jobject BuildClientPrincipal(JNIEnv *env, krb5_context kcontext, krb5_principal principalName) {

    // Get the full principal string.

    char *principalString = NULL;

    jobject principal = NULL;

    int err = krb5_unparse_name (kcontext, principalName, &principalString);

    if (!err) {

        // Make a PrincipalName from the full string and the type.  Let the PrincipalName class parse it out.

        jstring principalStringObj = (*env)->NewStringUTF(env, principalString);

        if (principalStringObj == NULL) {

            if (principalString != NULL) { krb5_free_unparsed_name (kcontext, principalString); }

            return (jobject) NULL;

        }

        principal = (*env)->NewObject(env, principalNameClass, principalNameConstructor, principalStringObj, principalName->type);

        if (principalString != NULL) { krb5_free_unparsed_name (kcontext, principalString); }

        (*env)->DeleteLocalRef(env, principalStringObj);

    }

    return principal;

}

jobject BuildEncryptionKey(JNIEnv *env, krb5_keyblock *cryptoKey) {

    // First, need to build a byte array

    jbyteArray ary;

    jobject encryptionKey = NULL;

    ary = (*env)->NewByteArray(env,cryptoKey->length);

    if (ary == NULL) {

        return (jobject) NULL;

    }

    (*env)->SetByteArrayRegion(env, ary, (jsize) 0, cryptoKey->length, (jbyte *)cryptoKey->contents);

    if (!(*env)->ExceptionCheck(env)) {

        encryptionKey = (*env)->NewObject(env, encryptionKeyClass, encryptionKeyConstructor, cryptoKey->enctype, ary);

    }

    (*env)->DeleteLocalRef(env, ary);

    return encryptionKey;

}

jobject BuildTicketFlags(JNIEnv *env, krb5_flags flags) {

    jobject ticketFlags = NULL;

    jbyteArray ary;

    /*

     * Convert the bytes to network byte order before copying

     * them to a Java byte array.

     */

    unsigned long nlflags = htonl(flags);

    ary = (*env)->NewByteArray(env, sizeof(flags));

    if (ary == NULL) {

        return (jobject) NULL;

    }

    (*env)->SetByteArrayRegion(env, ary, (jsize) 0, sizeof(flags), (jbyte *)&nlflags);

    if (!(*env)->ExceptionCheck(env)) {

        ticketFlags = (*env)->NewObject(env, ticketFlagsClass, ticketFlagsConstructor, sizeof(flags)*8, ary);

    }

    (*env)->DeleteLocalRef(env, ary);

    return ticketFlags;