/*

 * 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 <ctype.h>

#include <errno.h>

#include <sys/types.h>

#include <netinet/in.h>

#include <netinet/in_systm.h>

#include <netinet/ip.h>

#include <netinet/ip_icmp.h>

#include <stdlib.h>

#include <string.h>

#include <sys/time.h>

#include "net_util.h"

#include "java_net_Inet4AddressImpl.h"

#if defined(MACOSX)

extern jobjectArray lookupIfLocalhost(JNIEnv *env, const char *hostname, jboolean includeV6);

#endif

/* the initial size of our hostent buffers */

#ifndef NI_MAXHOST

#define NI_MAXHOST 1025

#endif

#define SET_NONBLOCKING(fd) {       \

    int flags = fcntl(fd, F_GETFL); \

    flags |= O_NONBLOCK;            \

    fcntl(fd, F_SETFL, flags);      \

}

/*

 * 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[NI_MAXHOST + 1];

    hostname[0] = '\0';

    if (gethostname(hostname, NI_MAXHOST) != 0) {

        strcpy(hostname, "localhost");

    } else {

        // try to resolve hostname via nameservice

        // if it is known but getnameinfo fails, hostname will still be the

        // value from gethostname

        struct addrinfo hints, *res;

        // make sure string is null-terminated

        hostname[NI_MAXHOST] = '\0';

        memset(&hints, 0, sizeof(hints));

        hints.ai_flags = AI_CANONNAME;

        hints.ai_family = AF_INET;

        if (getaddrinfo(hostname, NULL, &hints, &res) == 0) {

            getnameinfo(res->ai_addr, res->ai_addrlen, hostname, NI_MAXHOST,

                        NULL, 0, NI_NAMEREQD);

            freeaddrinfo(res);

        }

    }

    return (*env)->NewStringUTF(env, hostname);

}

/*

 * Find an internet address for a given hostname. Note that 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

 */

JNIEXPORT jobjectArray JNICALL

Java_java_net_Inet4AddressImpl_lookupAllHostAddr(JNIEnv *env, jobject this,

                                                 jstring host) {

    jobjectArray ret = NULL;

    const char *hostname;

    int error = 0;

    struct addrinfo hints, *res = NULL, *resNew = NULL, *last = NULL,

        *iterator;

    initInetAddressIDs(env);

    JNU_CHECK_EXCEPTION_RETURN(env, NULL);

    if (IS_NULL(host)) {

        JNU_ThrowNullPointerException(env, "host argument is null");

        return NULL;

    }

    hostname = JNU_GetStringPlatformChars(env, host, JNI_FALSE);

    CHECK_NULL_RETURN(hostname, NULL);

    // try once, with our static buffer

    memset(&hints, 0, sizeof(hints));

    hints.ai_flags = AI_CANONNAME;

    hints.ai_family = AF_INET;

    error = getaddrinfo(hostname, NULL, &hints, &res);

    if (error) {

#if defined(MACOSX)

        // If getaddrinfo fails try getifaddrs, see bug 8170910.

        ret = lookupIfLocalhost(env, hostname, JNI_FALSE);

        if (ret != NULL || (*env)->ExceptionCheck(env)) {

            goto cleanupAndReturn;

        }

#endif

        // report error

        NET_ThrowUnknownHostExceptionWithGaiError(env, hostname, error);

        goto cleanupAndReturn;

    } else {

        int i = 0;

        iterator = res;

        while (iterator != NULL) {

            // skip duplicates

            int skip = 0;

            struct addrinfo *iteratorNew = resNew;

            while (iteratorNew != NULL) {

                struct sockaddr_in *addr1, *addr2;

                addr1 = (struct sockaddr_in *)iterator->ai_addr;

                addr2 = (struct sockaddr_in *)iteratorNew->ai_addr;

                if (addr1->sin_addr.s_addr == addr2->sin_addr.s_addr) {

                    skip = 1;

                    break;

                }

                iteratorNew = iteratorNew->ai_next;

            }

            if (!skip) {

                struct addrinfo *next

                    = (struct addrinfo *)malloc(sizeof(struct addrinfo));

                if (!next) {

                    JNU_ThrowOutOfMemoryError(env, "Native heap allocation failed");

                    ret = NULL;

                    goto cleanupAndReturn;

                }

                memcpy(next, iterator, sizeof(struct addrinfo));

                next->ai_next = NULL;

                if (resNew == NULL) {

                    resNew = next;

                } else {

                    last->ai_next = next;

                }

                last = next;

                i++;

            }

            iterator = iterator->ai_next;

        }

        // allocate array - at this point i contains the number of addresses

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

        if (IS_NULL(ret)) {

            goto cleanupAndReturn;

        }

        i = 0;

        iterator = resNew;

        while (iterator != NULL) {

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

            if (IS_NULL(iaObj)) {

                ret = NULL;

                goto cleanupAndReturn;

            }

            setInetAddress_addr(env, iaObj, ntohl(((struct sockaddr_in *)

                                (iterator->ai_addr))->sin_addr.s_addr));

            setInetAddress_hostName(env, iaObj, host);

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

            iterator = iterator->ai_next;

        }

    }

cleanupAndReturn:

    JNU_ReleaseStringPlatformChars(env, host, hostname);

    while (resNew != NULL) {

        last = resNew;

        resNew = resNew->ai_next;

        free(last);

    }

    if (res != NULL) {

        freeaddrinfo(res);

    }

    return ret;

}

/*

 * Class:     java_net_Inet4AddressImpl

 * Method:    getHostByAddr

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

 *

 * Theoretically the UnknownHostException could be enriched with gai error

 * information. But as it is silently ignored anyway, there's no need for this.

 * It's only important that either a valid hostname is returned or an

 * UnknownHostException is thrown.

 */

JNIEXPORT jstring JNICALL

Java_java_net_Inet4AddressImpl_getHostByAddr(JNIEnv *env, jobject this,

                                             jbyteArray addrArray) {

    jstring ret = NULL;

    char host[NI_MAXHOST + 1];

    jbyte caddr[4];

    jint addr;

    struct sockaddr_in sa;

    // construct a sockaddr_in structure

    memset((char *)&sa, 0, sizeof(struct sockaddr_in));

    (*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);

    sa.sin_addr.s_addr = htonl(addr);

    sa.sin_family = AF_INET;

    if (getnameinfo((struct sockaddr *)&sa, sizeof(struct sockaddr_in),

                    host, NI_MAXHOST, NULL, 0, NI_NAMEREQD)) {

        JNU_ThrowByName(env, "java/net/UnknownHostException", NULL);

    } else {

        ret = (*env)->NewStringUTF(env, host);

        if (ret == NULL) {

            JNU_ThrowByName(env, "java/net/UnknownHostException", NULL);

        }

    }

    return ret;

}

/**

 * ping implementation using tcp port 7 (echo)

 */

static jboolean

tcp_ping4(JNIEnv *env, SOCKETADDRESS *sa, SOCKETADDRESS *netif, jint timeout,

          jint ttl)

{

    jint fd;

    int connect_rv = -1;

    // open a TCP socket

    fd = 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, errno, "Can't create socket");

        return JNI_FALSE;

    }

    // set TTL

    if (ttl > 0) {

        setsockopt(fd, IPPROTO_IP, IP_TTL, &ttl, sizeof(ttl));

    }

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

    if (netif != NULL) {

        if (bind(fd, &netif->sa, sizeof(struct sockaddr_in)) < 0) {

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

            close(fd);

            return JNI_FALSE;

        }

    }

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

    SET_NONBLOCKING(fd);

    sa->sa4.sin_port = htons(7); // echo port

    connect_rv = NET_Connect(fd, &sa->sa, sizeof(struct sockaddr_in));

    // connection established or refused immediately, either way it means

    // we were able to reach the host!

    if (connect_rv == 0 || errno == ECONNREFUSED) {

        close(fd);

        return JNI_TRUE;

    }

    switch (errno) {

    case ENETUNREACH:   // Network Unreachable

    case EAFNOSUPPORT:  // Address Family not supported

    case EADDRNOTAVAIL: // address is not available on the remote machine

#if defined(__linux__) || defined(_AIX)

        // On some Linux versions, when a socket is bound to the loopback

        // interface, connect will fail and errno will be set to EINVAL

        // or EHOSTUNREACH.  When that happens, don't throw an exception,

        // just return false.

    case EINVAL:

    case EHOSTUNREACH:  // No route to host

#endif

        close(fd);

        return JNI_FALSE;

    case EINPROGRESS:   // this is expected as we'll probably have to wait

        break;

    default:

        NET_ThrowByNameWithLastError(env, JNU_JAVANETPKG "ConnectException",

                                     "connect failed");

        close(fd);

        return JNI_FALSE;

    }

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

    if (timeout >= 0) {

        // connection has been established, check for error condition

        socklen_t optlen = (socklen_t)sizeof(connect_rv);

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

                       &optlen) <0)

        {

            connect_rv = errno;

        }

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

            close(fd);

            return JNI_TRUE;

        }

    }

    close(fd);

    return JNI_FALSE;

}

/**

 * ping implementation.

 * Send an ICMP_ECHO_REQUEST packet every second until either the timeout

 * expires or an answer is received.

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

 */

static jboolean

ping4(JNIEnv *env, jint fd, SOCKETADDRESS *sa, SOCKETADDRESS *netif,

      jint timeout, jint ttl)

{

    jint n, size = 60 * 1024, hlen, tmout2, seq = 1;

    socklen_t len;

    unsigned char sendbuf[1500], recvbuf[1500];

    struct icmp *icmp;

    struct ip *ip;

    struct sockaddr_in sa_recv;

    jchar pid;

    struct timeval tv;

    size_t plen = ICMP_ADVLENMIN + sizeof(tv);

    setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &size, sizeof(size));

    // sets the ttl (max number of hops)

    if (ttl > 0) {

        setsockopt(fd, IPPROTO_IP, IP_TTL, &ttl, sizeof(ttl));

    }

    // a specific interface was specified, so let's bind the socket

    // to that interface to ensure the requests are sent only through it.

    if (netif != NULL) {

        if (bind(fd, &netif->sa, sizeof(struct sockaddr_in)) < 0) {

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

            close(fd);

            return JNI_FALSE;

        }

    }

    // icmp_id is a 16 bit data type, therefore down cast the pid

    pid = (jchar)getpid();

    // Make the socket non blocking so we can use select

    SET_NONBLOCKING(fd);

    do {

        // create the ICMP request

        icmp = (struct icmp *)sendbuf;

        icmp->icmp_type = ICMP_ECHO;

        icmp->icmp_code = 0;

        // let's tag the ECHO packet with our pid so we can identify it

        icmp->icmp_id = htons(pid);

        icmp->icmp_seq = htons(seq);

        seq++;

        gettimeofday(&tv, NULL);

        memcpy(icmp->icmp_data, &tv, sizeof(tv));

        icmp->icmp_cksum = 0;

        // manually calculate checksum

        icmp->icmp_cksum = in_cksum((u_short *)icmp, plen);

        // send it

        n = sendto(fd, sendbuf, plen, 0, &sa->sa, sizeof(struct sockaddr_in));

        if (n < 0 && errno != EINPROGRESS) {

#if defined(__linux__)

            /*

             * On some Linux versions, when a socket is bound to the loopback

             * interface, sendto will fail and errno will be set to

             * EINVAL or EHOSTUNREACH. When that happens, don't throw an

             * exception, just return false.

             */

            if (errno != EINVAL && errno != EHOSTUNREACH) {

                NET_ThrowNew(env, errno, "Can't send ICMP packet");

            }

#else

            NET_ThrowNew(env, errno, "Can't send ICMP packet");

#endif

            close(fd);

            return JNI_FALSE;

        }

        tmout2 = timeout > 1000 ? 1000 : timeout;

        do {

            tmout2 = NET_Wait(env, fd, NET_WAIT_READ, tmout2);

            if (tmout2 >= 0) {

                len = sizeof(sa_recv);

                n = recvfrom(fd, recvbuf, sizeof(recvbuf), 0,

                             (struct sockaddr *)&sa_recv, &len);

                // check if we received enough data

                if (n < (jint)sizeof(struct ip)) {

                    continue;

                }

                ip = (struct ip *)recvbuf;

                hlen = ((jint)(unsigned int)(ip->ip_hl)) << 2;

                // check if we received enough data

                if (n < (jint)(hlen + sizeof(struct icmp))) {

                    continue;

                }

                icmp = (struct icmp *)(recvbuf + hlen);

                // We did receive something, but is it what we were expecting?

                // I.E.: An ICMP_ECHO_REPLY packet with the proper PID and

                //       from the host that we are trying to determine is reachable.

                if (icmp->icmp_type == ICMP_ECHOREPLY &&

                    (ntohs(icmp->icmp_id) == pid))

                {

                    if (sa->sa4.sin_addr.s_addr == sa_recv.sin_addr.s_addr) {

                        close(fd);

                        return JNI_TRUE;

                    } else if (sa->sa4.sin_addr.s_addr == 0) {

                        close(fd);

                        return JNI_TRUE;

                    }

                }

            }

        } while (tmout2 > 0);

        timeout -= 1000;

    } while (timeout > 0);

    close(fd);

    return JNI_FALSE;

}

/*

 * Class:     java_net_Inet4AddressImpl

 * Method:    isReachable0

 * Signature: ([bI[bI)Z

 */

JNIEXPORT jboolean JNICALL

Java_java_net_Inet4AddressImpl_isReachable0(JNIEnv *env, jobject this,

                                            jbyteArray addrArray, jint timeout,

                                            jbyteArray ifArray, jint ttl)

{

    jbyte caddr[4];

    jint addr = 0, sz, fd;

    SOCKETADDRESS sa, inf, *netif = NULL;

    // check if address array size is 4 (IPv4 address)

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

    if (sz != 4) {

      return JNI_FALSE;

    }

    // convert IP address from byte array to integer

    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);

    memset((char *)&sa, 0, sizeof(SOCKETADDRESS));

    sa.sa4.sin_addr.s_addr = htonl(addr);