/*

 * Copyright (c) 2000, 2013, 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 <winsock2.h>

#include <ctype.h>

#include <stdio.h>

#include <stdlib.h>

#include <malloc.h>

#include <sys/types.h>

#include <process.h>

#include <iphlpapi.h>

#include <icmpapi.h>

#include "java_net_InetAddress.h"

#include "java_net_Inet4AddressImpl.h"

#include "net_util.h"

#include "icmp.h"

/*

 * Returns true if hostname is in dotted IP address format. Note that this

 * function performs a syntax check only. For each octet it just checks that

 * the octet is at most 3 digits.

 */

jboolean isDottedIPAddress(const char *hostname, unsigned int *addrp) {

    char *c = (char *)hostname;

    int octets = 0;

    unsigned int cur = 0;

    int digit_cnt = 0;

    while (*c) {

        if (*c == '.') {

            if (digit_cnt == 0) {

                return JNI_FALSE;

            } else {

                if (octets < 4) {

                    addrp[octets++] = cur;

                    cur = 0;

                    digit_cnt = 0;

                } else {

                    return JNI_FALSE;

                }

            }

            c++;

            continue;

        }

        if ((*c < '0') || (*c > '9')) {

            return JNI_FALSE;

        }

        digit_cnt++;

        if (digit_cnt > 3) {

            return JNI_FALSE;

        }

        /* don't check if current octet > 255 */

        cur = cur*10 + (*c - '0');

        /* Move onto next character and check for EOF */

        c++;

        if (*c == '\0') {

            if (octets < 4) {

                addrp[octets++] = cur;

            } else {

                return JNI_FALSE;

            }

        }

    }

    return (jboolean)(octets == 4);

}

/*

 * Inet4AddressImpl

 */

/*

 * Class:     java_net_Inet4AddressImpl

 * Method:    getLocalHostName

 * Signature: ()Ljava/lang/String;

 */

JNIEXPORT jstring JNICALL

Java_java_net_Inet4AddressImpl_getLocalHostName (JNIEnv *env, jobject this) {

    char hostname[256];

    if (gethostname(hostname, sizeof hostname) == -1) {

        strcpy(hostname, "localhost");

    }

    return JNU_NewStringPlatform(env, hostname);

}

/*

 * Find an internet address for a given hostname.  Not this this

 * code only works for addresses of type INET. The translation

 * of %d.%d.%d.%d to an address (int) occurs in java now, so the

 * String "host" shouldn't be a %d.%d.%d.%d string. The only

 * exception should be when any of the %d are out of range and

 * we fallback to a lookup.

 *

 * Class:     java_net_Inet4AddressImpl

 * Method:    lookupAllHostAddr

 * Signature: (Ljava/lang/String;)[[B

 *

 * This is almost shared code

 */

JNIEXPORT jobjectArray JNICALL

Java_java_net_Inet4AddressImpl_lookupAllHostAddr(JNIEnv *env, jobject this,

                                                jstring host) {

    const char *hostname;

    struct hostent *hp;

    unsigned int addr[4];

    jobjectArray ret = NULL;

    initInetAddressIDs(env);

    JNU_CHECK_EXCEPTION_RETURN(env, NULL);

    if (IS_NULL(host)) {

        JNU_ThrowNullPointerException(env, "host argument");

        return NULL;

    }

    hostname = JNU_GetStringPlatformChars(env, host, JNI_FALSE);

    CHECK_NULL_RETURN(hostname, NULL);

    /*

     * The NT/2000 resolver tolerates a space in front of localhost. This

     * is not consistent with other implementations of gethostbyname.

     * In addition we must do a white space check on Solaris to avoid a

     * bug whereby 0.0.0.0 is returned if any host name has a white space.

     */

    if (isspace(hostname[0])) {

        JNU_ThrowByName(env, JNU_JAVANETPKG "UnknownHostException", hostname);

        goto cleanupAndReturn;

    }

    /*

     * If the format is x.x.x.x then don't use gethostbyname as Windows

     * is unable to handle octets which are out of range.

     */

    if (isDottedIPAddress(hostname, &addr[0])) {

        unsigned int address;

        jobject iaObj;

        /*

         * Are any of the octets out of range?

         */

        if (addr[0] > 255 || addr[1] > 255 || addr[2] > 255 || addr[3] > 255) {

            JNU_ThrowByName(env, JNU_JAVANETPKG "UnknownHostException", hostname);

            goto cleanupAndReturn;

        }

        /*

         * Return an byte array with the populated address.

         */

        address = (addr[3]<<24) & 0xff000000;

        address |= (addr[2]<<16) & 0xff0000;

        address |= (addr[1]<<8) & 0xff00;

        address |= addr[0];

        ret = (*env)->NewObjectArray(env, 1, ia_class, NULL);

        if (IS_NULL(ret)) {

            goto cleanupAndReturn;

        }

        iaObj = (*env)->NewObject(env, ia4_class, ia4_ctrID);

        if (IS_NULL(iaObj)) {

          ret = NULL;

          goto cleanupAndReturn;

        }

        setInetAddress_addr(env, iaObj, ntohl(address));

        (*env)->SetObjectArrayElement(env, ret, 0, iaObj);

        JNU_ReleaseStringPlatformChars(env, host, hostname);

        return ret;

    }

    /*

     * Perform the lookup

     */

    if ((hp = gethostbyname((char*)hostname)) != NULL) {

        struct in_addr **addrp = (struct in_addr **) hp->h_addr_list;

        int len = sizeof(struct in_addr);

        int i = 0;

        while (*addrp != (struct in_addr *) 0) {

            i++;

            addrp++;

        }

        ret = (*env)->NewObjectArray(env, i, ia_class, NULL);

        if (IS_NULL(ret)) {

            goto cleanupAndReturn;

        }

        addrp = (struct in_addr **) hp->h_addr_list;

        i = 0;

        while (*addrp != (struct in_addr *) 0) {

          jobject iaObj = (*env)->NewObject(env, ia4_class, ia4_ctrID);

          if (IS_NULL(iaObj)) {

            ret = NULL;

            goto cleanupAndReturn;

          }

          setInetAddress_addr(env, iaObj, ntohl((*addrp)->s_addr));

          setInetAddress_hostName(env, iaObj, host);

          (*env)->SetObjectArrayElement(env, ret, i, iaObj);

          addrp++;

          i++;

        }

    } else if (WSAGetLastError() == WSATRY_AGAIN) {

        NET_ThrowByNameWithLastError(env,

                                     JNU_JAVANETPKG "UnknownHostException",

                                     hostname);

    } else {

        JNU_ThrowByName(env, JNU_JAVANETPKG "UnknownHostException", hostname);

    }

cleanupAndReturn:

    JNU_ReleaseStringPlatformChars(env, host, hostname);

    return ret;

}

/*

 * Class:     java_net_Inet4AddressImpl

 * Method:    getHostByAddr

 * Signature: (I)Ljava/lang/String;

 */

JNIEXPORT jstring JNICALL

Java_java_net_Inet4AddressImpl_getHostByAddr(JNIEnv *env, jobject this,

                                            jbyteArray addrArray) {

    struct hostent *hp;

    jbyte caddr[4];

    jint addr;

    (*env)->GetByteArrayRegion(env, addrArray, 0, 4, caddr);

    addr = ((caddr[0]<<24) & 0xff000000);

    addr |= ((caddr[1] <<16) & 0xff0000);

    addr |= ((caddr[2] <<8) & 0xff00);

    addr |= (caddr[3] & 0xff);

    addr = htonl(addr);

    hp = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET);

    if (hp == NULL) {

        JNU_ThrowByName(env, JNU_JAVANETPKG "UnknownHostException", 0);

        return NULL;

    }

    if (hp->h_name == NULL) { /* Deal with bug in Windows XP */

        JNU_ThrowByName(env, JNU_JAVANETPKG "UnknownHostException", 0);

        return NULL;

    }

    return JNU_NewStringPlatform(env, hp->h_name);

}

static jboolean

tcp_ping4(JNIEnv *env,

          jbyteArray addrArray,

          jint timeout,

          jbyteArray ifArray,

          jint ttl)

{

    jint addr;

    jbyte caddr[4];

    jint fd;

    struct sockaddr_in him;

    struct sockaddr_in* netif = NULL;

    struct sockaddr_in inf;

    int len = 0;

    WSAEVENT hEvent;

    int connect_rv = -1;

    int sz;

    /**

     * Convert IP address from byte array to integer

     */

    sz = (*env)->GetArrayLength(env, addrArray);

    if (sz != 4) {

        return JNI_FALSE;

    }

    memset((char *) &him, 0, sizeof(him));

    memset((char *) caddr, 0, sizeof(caddr));

    (*env)->GetByteArrayRegion(env, addrArray, 0, 4, caddr);

    addr = ((caddr[0]<<24) & 0xff000000);

    addr |= ((caddr[1] <<16) & 0xff0000);

    addr |= ((caddr[2] <<8) & 0xff00);

    addr |= (caddr[3] & 0xff);

    addr = htonl(addr);

    /**

     * Socket address

     */

    him.sin_addr.s_addr = addr;

    him.sin_family = AF_INET;

    len = sizeof(him);

    /**

     * If a network interface was specified, let's convert its address

     * as well.

     */

    if (!(IS_NULL(ifArray))) {

        memset((char *) caddr, 0, sizeof(caddr));

        (*env)->GetByteArrayRegion(env, ifArray, 0, 4, caddr);

        addr = ((caddr[0]<<24) & 0xff000000);

        addr |= ((caddr[1] <<16) & 0xff0000);

        addr |= ((caddr[2] <<8) & 0xff00);

        addr |= (caddr[3] & 0xff);

        addr = htonl(addr);

        inf.sin_addr.s_addr = addr;

        inf.sin_family = AF_INET;

        inf.sin_port = 0;

        netif = &inf;

    }

    /*

     * Can't create a raw socket, so let's try a TCP socket

     */

    fd = NET_Socket(AF_INET, SOCK_STREAM, 0);

    if (fd == -1) {

        /* note: if you run out of fds, you may not be able to load

         * the exception class, and get a NoClassDefFoundError

         * instead.

         */

        NET_ThrowNew(env, WSAGetLastError(), "Can't create socket");

        return JNI_FALSE;

    }

    if (ttl > 0) {

        setsockopt(fd, IPPROTO_IP, IP_TTL, (const char *)&ttl, sizeof(ttl));

    }

    /*

     * A network interface was specified, so let's bind to it.

     */

    if (netif != NULL) {

        if (bind(fd, (struct sockaddr*)netif, sizeof(struct sockaddr_in)) < 0) {

            NET_ThrowNew(env, WSAGetLastError(), "Can't bind socket");

            closesocket(fd);

            return JNI_FALSE;

        }

    }

    /*

     * Make the socket non blocking so we can use select/poll.

     */

    hEvent = WSACreateEvent();

    WSAEventSelect(fd, hEvent, FD_READ|FD_CONNECT|FD_CLOSE);

    /* no need to use NET_Connect as non-blocking */

    him.sin_port = htons(7);    /* Echo */

    connect_rv = connect(fd, (struct sockaddr *)&him, len);

    /**

     * connection established or refused immediately, either way it means

     * we were able to reach the host!

     */

    if (connect_rv == 0 || WSAGetLastError() == WSAECONNREFUSED) {

        WSACloseEvent(hEvent);

        closesocket(fd);

        return JNI_TRUE;

    } else {

        int optlen;

        switch (WSAGetLastError()) {

        case WSAEHOSTUNREACH:   /* Host Unreachable */

        case WSAENETUNREACH:    /* Network Unreachable */

        case WSAENETDOWN:       /* Network is down */

        case WSAEPFNOSUPPORT:   /* Protocol Family unsupported */

            WSACloseEvent(hEvent);

            closesocket(fd);

            return JNI_FALSE;

        }

        if (WSAGetLastError() != WSAEWOULDBLOCK) {

            NET_ThrowByNameWithLastError(env, JNU_JAVANETPKG "ConnectException",

                                         "connect failed");

            WSACloseEvent(hEvent);

            closesocket(fd);

            return JNI_FALSE;

        }

        timeout = NET_Wait(env, fd, NET_WAIT_CONNECT, timeout);

        /* has connection been established */

        if (timeout >= 0) {

            optlen = sizeof(connect_rv);

            if (getsockopt(fd, SOL_SOCKET, SO_ERROR, (void*)&connect_rv,

                           &optlen) <0) {

                connect_rv = WSAGetLastError();

            }

            if (connect_rv == 0 || connect_rv == WSAECONNREFUSED) {

                WSACloseEvent(hEvent);

                closesocket(fd);

                return JNI_TRUE;

            }

        }

    }

    WSACloseEvent(hEvent);

    closesocket(fd);

    return JNI_FALSE;

}

/**

 * ping implementation.

 * Send a ICMP_ECHO_REQUEST packet every second until either the timeout

 * expires or a answer is received.

 * Returns true is an ECHO_REPLY is received, otherwise, false.

 */

static jboolean

ping4(JNIEnv *env,

      unsigned long src_addr,

      unsigned long dest_addr,

      jint timeout,

      HANDLE hIcmpFile)

{

    // See https://msdn.microsoft.com/en-us/library/aa366050%28VS.85%29.aspx

    DWORD dwRetVal = 0;

    char SendData[32] = {0};

    LPVOID ReplyBuffer = NULL;

    DWORD ReplySize = 0;

    jboolean ret = JNI_FALSE;

    ReplyBuffer = (VOID*) malloc(ReplySize);

    if (ReplyBuffer == NULL) {

        IcmpCloseHandle(hIcmpFile);

        NET_ThrowNew(env, WSAGetLastError(), "Unable to allocate memory");

        return JNI_FALSE;

    }

    if (src_addr == 0) {

        dwRetVal = IcmpSendEcho(hIcmpFile,  // HANDLE IcmpHandle,

                                dest_addr,  // IPAddr DestinationAddress,

                                SendData,   // LPVOID RequestData,

                                sizeof(SendData),   // WORD RequestSize,

                                NULL,       // PIP_OPTION_INFORMATION RequestOptions,

                                ReplyBuffer,// LPVOID ReplyBuffer,

                                ReplySize,  // DWORD ReplySize,

                                // Note: IcmpSendEcho and its derivatives

                                // seem to have an undocumented minimum

                                // timeout of 1000ms below which the

                                // api behaves inconsistently.

                                (timeout < 1000) ? 1000 : timeout);   // DWORD Timeout

    } else {

        dwRetVal = IcmpSendEcho2Ex(hIcmpFile,  // HANDLE IcmpHandle,

                                   NULL,       // HANDLE Event

                                   NULL,       // PIO_APC_ROUTINE ApcRoutine

                                   NULL,       // ApcContext

                                   src_addr,   // IPAddr SourceAddress,

                                   dest_addr,  // IPAddr DestinationAddress,

                                   SendData,   // LPVOID RequestData,

                                   sizeof(SendData),   // WORD RequestSize,

                                   NULL,       // PIP_OPTION_INFORMATION RequestOptions,

                                   ReplyBuffer,// LPVOID ReplyBuffer,

                                   ReplySize,  // DWORD ReplySize,

                                   (timeout < 1000) ? 1000 : timeout);   // DWORD Timeout

    }