jdk/src/windows/native/java/net/Inet6AddressImpl.c
changeset 2 90ce3da70b43
child 707 4e060643fb54
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/windows/native/java/net/Inet6AddressImpl.c	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,700 @@
+/*
+ * Copyright 2000-2006 Sun Microsystems, Inc.  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.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.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 "java_net_InetAddress.h"
+#include "java_net_Inet4AddressImpl.h"
+#include "java_net_Inet6AddressImpl.h"
+#include "net_util.h"
+#include "icmp.h"
+
+#ifdef WIN32
+#ifndef _WIN64
+
+/* Retain this code a little longer to support building in
+ * old environments.  _MSC_VER is defined as:
+ *     1200 for MSVC++ 6.0
+ *     1310 for Vc7
+ */
+#if defined(_MSC_VER) && _MSC_VER < 1310
+#define sockaddr_in6 SOCKADDR_IN6
+#endif
+#endif
+#define uint32_t UINT32
+#endif
+
+/*
+ * Inet6AddressImpl
+ */
+
+/*
+ * Class:     java_net_Inet6AddressImpl
+ * Method:    getLocalHostName
+ * Signature: ()Ljava/lang/String;
+ */
+JNIEXPORT jstring JNICALL
+Java_java_net_Inet6AddressImpl_getLocalHostName (JNIEnv *env, jobject this) {
+    char hostname [256];
+
+    if (gethostname (hostname, sizeof (hostname)) == -1) {
+        strcpy (hostname, "localhost");
+    }
+    return JNU_NewStringPlatform (env, hostname);
+}
+
+static jclass ni_iacls;
+static jclass ni_ia4cls;
+static jclass ni_ia6cls;
+static jmethodID ni_ia4ctrID;
+static jmethodID ni_ia6ctrID;
+static jfieldID ni_iaaddressID;
+static jfieldID ni_iahostID;
+static jfieldID ni_iafamilyID;
+static jfieldID ni_ia6ipaddressID;
+static int initialized = 0;
+
+JNIEXPORT jobjectArray JNICALL
+Java_java_net_Inet6AddressImpl_lookupAllHostAddr(JNIEnv *env, jobject this,
+                                                jstring host) {
+    const char *hostname;
+    jobject name;
+    jobjectArray ret = 0;
+    int retLen = 0;
+    jboolean preferIPv6Address;
+
+    int error=0;
+    struct addrinfo hints, *res, *resNew = NULL;
+
+    if (!initialized) {
+      ni_iacls = (*env)->FindClass(env, "java/net/InetAddress");
+      ni_iacls = (*env)->NewGlobalRef(env, ni_iacls);
+      ni_ia4cls = (*env)->FindClass(env, "java/net/Inet4Address");
+      ni_ia4cls = (*env)->NewGlobalRef(env, ni_ia4cls);
+      ni_ia6cls = (*env)->FindClass(env, "java/net/Inet6Address");
+      ni_ia6cls = (*env)->NewGlobalRef(env, ni_ia6cls);
+      ni_ia4ctrID = (*env)->GetMethodID(env, ni_ia4cls, "<init>", "()V");
+      ni_ia6ctrID = (*env)->GetMethodID(env, ni_ia6cls, "<init>", "()V");
+      ni_iaaddressID = (*env)->GetFieldID(env, ni_iacls, "address", "I");
+      ni_iafamilyID = (*env)->GetFieldID(env, ni_iacls, "family", "I");
+      ni_iahostID = (*env)->GetFieldID(env, ni_iacls, "hostName", "Ljava/lang/String;");
+      ni_ia6ipaddressID = (*env)->GetFieldID(env, ni_ia6cls, "ipaddress", "[B");
+      initialized = 1;
+    }
+    if (IS_NULL(host)) {
+        JNU_ThrowNullPointerException(env, "host is null");
+        return 0;
+    }
+    hostname = JNU_GetStringPlatformChars(env, host, JNI_FALSE);
+    CHECK_NULL_RETURN(hostname, NULL);
+
+    if (NET_addrtransAvailable()) {
+        static jfieldID ia_preferIPv6AddressID;
+        if (ia_preferIPv6AddressID == NULL) {
+            jclass c = (*env)->FindClass(env,"java/net/InetAddress");
+            if (c)  {
+                ia_preferIPv6AddressID =
+                    (*env)->GetStaticFieldID(env, c, "preferIPv6Address", "Z");
+            }
+            if (ia_preferIPv6AddressID == NULL) {
+                JNU_ReleaseStringPlatformChars(env, host, hostname);
+                return NULL;
+            }
+        }
+        /* get the address preference */
+        preferIPv6Address
+            = (*env)->GetStaticBooleanField(env, ia_class, ia_preferIPv6AddressID);
+
+        /* Try once, with our static buffer. */
+        memset(&hints, 0, sizeof(hints));
+        hints.ai_flags = AI_CANONNAME;
+        hints.ai_family = AF_UNSPEC;
+
+        error = (*getaddrinfo_ptr)(hostname, NULL, &hints, &res);
+
+        if (error) {
+            /* report error */
+            JNU_ThrowByName(env, JNU_JAVANETPKG "UnknownHostException",
+                            (char *)hostname);
+            JNU_ReleaseStringPlatformChars(env, host, hostname);
+            return NULL;
+        } else {
+            int i = 0;
+            int inetCount = 0, inet6Count = 0, inetIndex, inet6Index;
+            struct addrinfo *itr, *last, *iterator = res;
+            while (iterator != NULL) {
+                int skip = 0;
+                itr = resNew;
+                while (itr != NULL) {
+                    if (iterator->ai_family == itr->ai_family &&
+                        iterator->ai_addrlen == itr->ai_addrlen) {
+                        if (itr->ai_family == AF_INET) { /* AF_INET */
+                            struct sockaddr_in *addr1, *addr2;
+                            addr1 = (struct sockaddr_in *)iterator->ai_addr;
+                            addr2 = (struct sockaddr_in *)itr->ai_addr;
+                            if (addr1->sin_addr.s_addr ==
+                                addr2->sin_addr.s_addr) {
+                                skip = 1;
+                                break;
+                            }
+                        } else {
+                            int t;
+                            struct sockaddr_in6 *addr1, *addr2;
+                            addr1 = (struct sockaddr_in6 *)iterator->ai_addr;
+                            addr2 = (struct sockaddr_in6 *)itr->ai_addr;
+
+                            for (t = 0; t < 16; t++) {
+                                if (addr1->sin6_addr.s6_addr[t] !=
+                                    addr2->sin6_addr.s6_addr[t]) {
+                                    break;
+                                }
+                            }
+                            if (t < 16) {
+                                itr = itr->ai_next;
+                                continue;
+                            } else {
+                                skip = 1;
+                                break;
+                            }
+                        }
+                    } else if (iterator->ai_family != AF_INET &&
+                               iterator->ai_family != AF_INET6) {
+                        /* we can't handle other family types */
+                        skip = 1;
+                        break;
+                    }
+                    itr = itr->ai_next;
+                }
+
+                if (!skip) {
+                    struct addrinfo *next
+                        = (struct addrinfo*) malloc(sizeof(struct addrinfo));
+                    if (!next) {
+                        JNU_ThrowOutOfMemoryError(env, "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++;
+                    if (iterator->ai_family == AF_INET) {
+                        inetCount ++;
+                    } else if (iterator->ai_family == AF_INET6) {
+                        inet6Count ++;
+                    }
+                }
+                iterator = iterator->ai_next;
+            }
+            retLen = i;
+            iterator = resNew;
+            i = 0;
+            ret = (*env)->NewObjectArray(env, retLen, ni_iacls, NULL);
+
+            if (IS_NULL(ret)) {
+                /* we may have memory to free at the end of this */
+                goto cleanupAndReturn;
+            }
+
+            if (preferIPv6Address) {
+                inetIndex = inet6Count;
+                inet6Index = 0;
+            } else {
+                inetIndex = 0;
+                inet6Index = inetCount;
+            }
+
+            name = (*env)->NewStringUTF(env, hostname);
+            if (IS_NULL(name)) {
+              ret = NULL;
+              goto cleanupAndReturn;
+            }
+
+            while (iterator != NULL) {
+                if (iterator->ai_family == AF_INET) {
+                  jobject iaObj = (*env)->NewObject(env, ni_ia4cls, ni_ia4ctrID);
+                  if (IS_NULL(iaObj)) {
+                    ret = NULL;
+                    goto cleanupAndReturn;
+                  }
+                  (*env)->SetIntField(env, iaObj, ni_iaaddressID,
+                                      ntohl(((struct sockaddr_in*)iterator->ai_addr)->sin_addr.s_addr));
+                  (*env)->SetObjectField(env, iaObj, ni_iahostID, name);
+                  (*env)->SetObjectArrayElement(env, ret, inetIndex, iaObj);
+                    inetIndex ++;
+                } else if (iterator->ai_family == AF_INET6) {
+                  jint scope = 0;
+                  jbyteArray ipaddress;
+                  jobject iaObj = (*env)->NewObject(env, ni_ia6cls, ni_ia6ctrID);
+                  if (IS_NULL(iaObj)) {
+                    ret = NULL;
+                    goto cleanupAndReturn;
+                  }
+                  ipaddress = (*env)->NewByteArray(env, 16);
+                  if (IS_NULL(ipaddress)) {
+                    ret = NULL;
+                    goto cleanupAndReturn;
+                  }
+                  (*env)->SetByteArrayRegion(env, ipaddress, 0, 16,
+                                             (jbyte *)&(((struct sockaddr_in6*)iterator->ai_addr)->sin6_addr));
+                  scope = ((struct sockaddr_in6*)iterator->ai_addr)->sin6_scope_id;
+                  if (scope != 0) { /* zero is default value, no need to set */
+                    (*env)->SetIntField(env, iaObj, ia6_scopeidID, scope);
+                    (*env)->SetBooleanField(env, iaObj, ia6_scopeidsetID, JNI_TRUE);
+                  }
+                  (*env)->SetObjectField(env, iaObj, ni_ia6ipaddressID, ipaddress);
+                  (*env)->SetObjectField(env, iaObj, ni_iahostID, name);
+                  (*env)->SetObjectArrayElement(env, ret, inet6Index, iaObj);
+                  inet6Index ++;
+                }
+                iterator = iterator->ai_next;
+            }
+        }
+    }
+
+cleanupAndReturn:
+    {
+        struct addrinfo *iterator, *tmp;
+        iterator = resNew;
+        while (iterator != NULL) {
+            tmp = iterator;
+            iterator = iterator->ai_next;
+            free(tmp);
+        }
+        JNU_ReleaseStringPlatformChars(env, host, hostname);
+    }
+
+    if (NET_addrtransAvailable())
+        (*freeaddrinfo_ptr)(res);
+
+    return ret;
+}
+
+/*
+ * Class:     java_net_Inet6AddressImpl
+ * Method:    getHostByAddr
+ * Signature: (I)Ljava/lang/String;
+ */
+JNIEXPORT jstring JNICALL
+Java_java_net_Inet6AddressImpl_getHostByAddr(JNIEnv *env, jobject this,
+                                            jbyteArray addrArray) {
+    jstring ret = NULL;
+
+    char host[NI_MAXHOST+1];
+    jfieldID fid;
+    int error = 0;
+    jint family;
+    struct sockaddr *him ;
+    int len = 0;
+    jbyte caddr[16];
+
+    if (NET_addrtransAvailable()) {
+        struct sockaddr_in him4;
+        struct sockaddr_in6 him6;
+        struct sockaddr *sa;
+
+        /*
+         * For IPv4 addresses construct a sockaddr_in structure.
+         */
+        if ((*env)->GetArrayLength(env, addrArray) == 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);
+            memset((char *) &him4, 0, sizeof(him4));
+            him4.sin_addr.s_addr = (uint32_t) htonl(addr);
+            him4.sin_family = AF_INET;
+            sa = (struct sockaddr *) &him4;
+            len = sizeof(him4);
+        } else {
+            /*
+             * For IPv6 address construct a sockaddr_in6 structure.
+             */
+            (*env)->GetByteArrayRegion(env, addrArray, 0, 16, caddr);
+            memset((char *) &him6, 0, sizeof(him6));
+            memcpy((void *)&(him6.sin6_addr), caddr, sizeof(struct in6_addr) );
+            him6.sin6_family = AF_INET6;
+            sa = (struct sockaddr *) &him6 ;
+            len = sizeof(him6) ;
+        }
+
+        error = (*getnameinfo_ptr)(sa, len, host, NI_MAXHOST, NULL, 0,
+                                   NI_NAMEREQD);
+
+        if (!error) {
+            ret = (*env)->NewStringUTF(env, host);
+        }
+    }
+
+    if (ret == NULL) {
+        JNU_ThrowByName(env, JNU_JAVANETPKG "UnknownHostException", NULL);
+    }
+
+    return ret;
+}
+
+#ifdef AF_INET6
+
+
+/**
+ * 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
+ping6(JNIEnv *env, jint fd, struct SOCKADDR_IN6* him, jint timeout,
+      struct SOCKADDR_IN6* netif, jint ttl) {
+    jint size;
+    jint n, len, hlen1, icmplen, i;
+    char sendbuf[1500];
+    char auxbuf[1500];
+    unsigned char recvbuf[1500];
+    struct icmp6_hdr *icmp6;
+    struct SOCKADDR_IN6 sa_recv;
+    unsigned short pid, seq;
+    int read_rv = 0;
+    WSAEVENT hEvent;
+    struct ip6_pseudo_hdr *pseudo_ip6;
+    int timestamp;
+    int tmout2;
+
+    /* Initialize the sequence number to a suitable random number and
+       shift right one place to allow sufficient room for increamenting. */
+    seq = ((unsigned short)rand()) >> 1;
+
+    /* icmp_id is a 16 bit data type, therefore down cast the pid */
+    pid = (unsigned short) getpid();
+
+    size = 60*1024;
+    setsockopt(fd, SOL_SOCKET, SO_RCVBUF, (const char *)&size, sizeof(size));
+    /**
+     * A TTL was specified, let's set the socket option.
+     */
+    if (ttl > 0) {
+      setsockopt(fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, (const char *) &ttl, sizeof(ttl));
+    }
+
+    /**
+     * A network interface was specified, let's bind to it.
+     */
+    if (netif != NULL) {
+      if (NET_Bind(fd, (struct sockaddr*)netif, sizeof(struct sockaddr_in6)) < 0){
+        NET_ThrowNew(env, WSAGetLastError(), "Can't bind socket to interface");
+        closesocket(fd);
+        return JNI_FALSE;
+      }
+    }
+
+    /*
+     * Make the socket non blocking
+     */
+    hEvent = WSACreateEvent();
+    WSAEventSelect(fd, hEvent, FD_READ|FD_CONNECT|FD_CLOSE);
+
+    /**
+     * send 1 ICMP REQUEST every second until either we get a valid reply
+     * or the timeout expired.
+     */
+    do {
+      /* let's tag the ECHO packet with our pid so we can identify it */
+      timestamp = GetCurrentTime();
+      memset(sendbuf, 0, 1500);
+      icmp6 = (struct icmp6_hdr *) sendbuf;
+      icmp6->icmp6_type = ICMP6_ECHO_REQUEST;
+      icmp6->icmp6_code = 0;
+      icmp6->icmp6_id = htons(pid);
+      icmp6->icmp6_seq = htons(seq);
+      icmp6->icmp6_cksum = 0;
+      memcpy((icmp6 + 1), &timestamp, sizeof(int));
+      if (netif != NULL) {
+        memset(auxbuf, 0, 1500);
+        pseudo_ip6 = (struct ip6_pseudo_hdr*) auxbuf;
+        memcpy(&pseudo_ip6->ip6_src, &netif->sin6_addr, sizeof(struct in6_addr));
+        memcpy(&pseudo_ip6->ip6_dst, &him->sin6_addr, sizeof(struct in6_addr));
+        pseudo_ip6->ip6_plen= htonl( 64 );
+        pseudo_ip6->ip6_nxt = htonl( IPPROTO_ICMPV6 );
+        memcpy(auxbuf + sizeof(struct ip6_pseudo_hdr), icmp6, 64);
+        /**
+         * We shouldn't have to do that as computing the checksum is supposed
+         * to be done by the IPv6 stack. Unfortunately windows, here too, is
+         * uterly broken, or non compliant, so let's do it.
+         * Problem is to compute the checksum I need to know the source address
+         * which happens only if I know the interface to be used...
+         */
+        icmp6->icmp6_cksum = in_cksum((u_short *)pseudo_ip6, sizeof(struct ip6_pseudo_hdr) + 64);
+      }
+
+      /**
+       * Ping!
+       */
+      n = sendto(fd, sendbuf, 64, 0, (struct sockaddr*) him, sizeof(struct sockaddr_in6));
+      if (n < 0 && (WSAGetLastError() == WSAEINTR || WSAGetLastError() == WSAEADDRNOTAVAIL)) {
+        // Happens when using a "tunnel interface" for instance.
+        // Or trying to send a packet on a different scope.
+        closesocket(fd);
+        WSACloseEvent(hEvent);
+        return JNI_FALSE;
+      }
+      if (n < 0 && WSAGetLastError() != WSAEWOULDBLOCK) {
+        NET_ThrowNew(env, WSAGetLastError(), "Can't send ICMP packet");
+        closesocket(fd);
+        WSACloseEvent(hEvent);
+        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);
+          memset(recvbuf, 0, 1500);
+          /**
+           * For some unknown reason, besides plain stupidity, windows
+           * truncates the first 4 bytes of the icmpv6 header some we can't
+           * check for the ICMP_ECHOREPLY value.
+           * we'll check the other values, though
+           */
+          n = recvfrom(fd, recvbuf + 4, sizeof(recvbuf) - 4, 0, (struct sockaddr*) &sa_recv, &len);
+          icmp6 = (struct icmp6_hdr *) (recvbuf);
+          memcpy(&i, (icmp6 + 1), sizeof(int));
+          /**
+           * Is that the reply we were expecting?
+           */
+          if (n >= 8 && ntohs(icmp6->icmp6_seq) == seq &&
+              ntohs(icmp6->icmp6_id) == pid && i == timestamp) {
+            closesocket(fd);
+            WSACloseEvent(hEvent);
+            return JNI_TRUE;
+          }
+        }
+      } while (tmout2 > 0);
+      timeout -= 1000;
+      seq++;
+    } while (timeout > 0);
+    closesocket(fd);
+    WSACloseEvent(hEvent);
+    return JNI_FALSE;
+}
+#endif /* AF_INET6 */
+
+/*
+ * Class:     java_net_Inet6AddressImpl
+ * Method:    isReachable0
+ * Signature: ([bII[bI)Z
+ */
+JNIEXPORT jboolean JNICALL
+Java_java_net_Inet6AddressImpl_isReachable0(JNIEnv *env, jobject this,
+                                           jbyteArray addrArray,
+                                           jint scope,
+                                           jint timeout,
+                                           jbyteArray ifArray,
+                                           jint ttl, jint if_scope) {
+#ifdef AF_INET6
+    jint addr;
+    jbyte caddr[16];
+    jint fd, sz;
+    struct sockaddr_in6 him6;
+    struct sockaddr_in6* netif = NULL;
+    struct sockaddr_in6 inf6;
+    WSAEVENT hEvent;
+    int len = 0;
+    int connect_rv = -1;
+
+    /*
+     * If IPv6 is not enable, then we can't reach an IPv6 address, can we?
+     * Actually, we probably shouldn't even get here.
+     */
+    if (!ipv6_available()) {
+      return JNI_FALSE;
+    }
+    /*
+     * If it's an IPv4 address, ICMP won't work with IPv4 mapped address,
+     * therefore, let's delegate to the Inet4Address method.
+     */
+    sz = (*env)->GetArrayLength(env, addrArray);
+    if (sz == 4) {
+      return Java_java_net_Inet4AddressImpl_isReachable0(env, this,
+                                                         addrArray,
+                                                         timeout,
+                                                         ifArray, ttl);
+    }
+
+    memset((char *) caddr, 0, 16);
+    memset((char *) &him6, 0, sizeof(him6));
+    (*env)->GetByteArrayRegion(env, addrArray, 0, 16, caddr);
+    memcpy((void *)&(him6.sin6_addr), caddr, sizeof(struct in6_addr) );
+    him6.sin6_family = AF_INET6;
+    if (scope > 0) {
+      him6.sin6_scope_id = scope;
+    }
+    len = sizeof(struct sockaddr_in6);
+    /**
+     * A network interface was specified, let's convert the address
+     */
+    if (!(IS_NULL(ifArray))) {
+      memset((char *) caddr, 0, 16);
+      memset((char *) &inf6, 0, sizeof(inf6));
+      (*env)->GetByteArrayRegion(env, ifArray, 0, 16, caddr);
+      memcpy((void *)&(inf6.sin6_addr), caddr, sizeof(struct in6_addr) );
+      inf6.sin6_family = AF_INET6;
+      inf6.sin6_port = 0;
+      inf6.sin6_scope_id = if_scope;
+      netif = &inf6;
+    }
+
+#if 0
+    /*
+     * Windows implementation of ICMP & RAW sockets is too unreliable for now.
+     * Therefore it's best not to try it at all and rely only on TCP
+     * We may revisit and enable this code in the future.
+     */
+
+    /*
+     * Right now, windows doesn't generate the ICMP checksum automatically
+     * so we have to compute it, but we can do it only if we know which
+     * interface will be used. Therefore, don't try to use ICMP if no
+     * interface was specified.
+     * When ICMPv6 support improves in windows, we may change this.
+     */
+    if (!(IS_NULL(ifArray))) {
+      /*
+       * If we can create a RAW socket, then when can use the ICMP ECHO_REQUEST
+       * otherwise we'll try a tcp socket to the Echo port (7).
+       * Note that this is empiric, and not connecting could mean it's blocked
+       * or the echo servioe has been disabled.
+       */
+      fd = NET_Socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6);
+
+      if (fd != -1) { /* Good to go, let's do a ping */
+        return ping6(env, fd, &him6, timeout, netif, ttl);
+      }
+    }
+#endif
+
+    /* No good, let's fall back on TCP */
+    fd = NET_Socket(AF_INET6, SOCK_STREAM, 0);
+    if (fd == JVM_IO_ERR) {
+        /* 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;
+    }
+
+    /**
+     * A TTL was specified, let's set the socket option.
+     */
+    if (ttl > 0) {
+      setsockopt(fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, (const char *)&ttl, sizeof(ttl));
+    }
+
+    /**
+     * A network interface was specified, let's bind to it.
+     */
+    if (netif != NULL) {
+      if (NET_Bind(fd, (struct sockaddr*)netif, sizeof(struct sockaddr_in6)) < 0) {
+        NET_ThrowNew(env, WSAGetLastError(), "Can't bind socket to interface");
+        closesocket(fd);
+        return JNI_FALSE;
+      }
+    }
+
+    /**
+     * Make the socket non blocking.
+     */
+    hEvent = WSACreateEvent();
+    WSAEventSelect(fd, hEvent, FD_READ|FD_CONNECT|FD_CLOSE);
+
+    /* no need to use NET_Connect as non-blocking */
+    him6.sin6_port = htons((short) 7); /* Echo port */
+    connect_rv = connect(fd, (struct sockaddr *)&him6, 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);
+
+        if (timeout >= 0) {
+          /* has connection been established? */
+          optlen = sizeof(connect_rv);
+          if (JVM_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);
+#endif /* AF_INET6 */
+    return JNI_FALSE;
+}