1 /*
   2  * Copyright (c) 2001, 2018, 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 #include "jni.h"
  27 #include "jni_util.h"
  28 #include "jvm.h"
  29 #include "jlong.h"
  30 
  31 #include <netdb.h>
  32 #include <sys/types.h>
  33 #include <sys/socket.h>
  34 #include <stdlib.h>
  35 #include <string.h>
  36 #include <errno.h>
  37 
  38 #if defined(__linux__) || defined(_ALLBSD_SOURCE)
  39 #include <netinet/in.h>
  40 #endif
  41 
  42 #include "net_util.h"
  43 #include "net_util_md.h"
  44 #include "nio.h"
  45 #include "nio_util.h"
  46 
  47 #include "sun_nio_ch_DatagramChannelImpl.h"
  48 
  49 static jfieldID dci_senderID;   /* sender in sun.nio.ch.DatagramChannelImpl */
  50 static jfieldID dci_senderAddrID; /* sender InetAddress in sun.nio.ch.DatagramChannelImpl */
  51 static jfieldID dci_senderPortID; /* sender port in sun.nio.ch.DatagramChannelImpl */
  52 static jclass isa_class;        /* java.net.InetSocketAddress */
  53 static jmethodID isa_ctorID;    /*   .InetSocketAddress(InetAddress, int) */
  54 
  55 JNIEXPORT void JNICALL
  56 Java_sun_nio_ch_DatagramChannelImpl_initIDs(JNIEnv *env, jclass clazz)
  57 {
  58     clazz = (*env)->FindClass(env, "java/net/InetSocketAddress");
  59     CHECK_NULL(clazz);
  60     isa_class = (*env)->NewGlobalRef(env, clazz);
  61     if (isa_class == NULL) {
  62         JNU_ThrowOutOfMemoryError(env, NULL);
  63         return;
  64     }
  65     isa_ctorID = (*env)->GetMethodID(env, clazz, "<init>",
  66                                      "(Ljava/net/InetAddress;I)V");
  67     CHECK_NULL(isa_ctorID);
  68 
  69     clazz = (*env)->FindClass(env, "sun/nio/ch/DatagramChannelImpl");
  70     CHECK_NULL(clazz);
  71     dci_senderID = (*env)->GetFieldID(env, clazz, "sender",
  72                                       "Ljava/net/SocketAddress;");
  73     CHECK_NULL(dci_senderID);
  74     dci_senderAddrID = (*env)->GetFieldID(env, clazz,
  75                                           "cachedSenderInetAddress",
  76                                           "Ljava/net/InetAddress;");
  77     CHECK_NULL(dci_senderAddrID);
  78     dci_senderPortID = (*env)->GetFieldID(env, clazz,
  79                                           "cachedSenderPort", "I");
  80     CHECK_NULL(dci_senderPortID);
  81 }
  82 
  83 JNIEXPORT void JNICALL
  84 Java_sun_nio_ch_DatagramChannelImpl_disconnect0(JNIEnv *env, jobject this,
  85                                                 jobject fdo, jboolean isIPv6)
  86 {
  87     jint fd = fdval(env, fdo);
  88     int rv;
  89 
  90 #if defined(__solaris__)
  91     rv = connect(fd, 0, 0);
  92 #else
  93     SOCKETADDRESS sa;
  94     socklen_t len = isIPv6 ? sizeof(struct sockaddr_in6) :
  95                              sizeof(struct sockaddr_in);
  96 
  97     memset(&sa, 0, sizeof(sa));
  98 #if defined(_ALLBSD_SOURCE)
  99     sa.sa.sa_family = isIPv6 ? AF_INET6 : AF_INET;
 100 #else
 101     sa.sa.sa_family = AF_UNSPEC;
 102 #endif
 103 
 104     rv = connect(fd, &sa.sa, len);
 105 
 106 #if defined(_ALLBSD_SOURCE)
 107     if (rv < 0 && errno == EADDRNOTAVAIL)
 108         rv = errno = 0;
 109 #elif defined(_AIX)
 110     /* See W. Richard Stevens, "UNIX Network Programming, Volume 1", p. 254:
 111      * 'Setting the address family to AF_UNSPEC might return EAFNOSUPPORT
 112      * but that is acceptable.
 113      */
 114     if (rv < 0 && errno == EAFNOSUPPORT)
 115         rv = errno = 0;
 116 #endif // defined(_ALLBSD_SOURCE) || defined(_AIX)
 117 
 118 #endif // defined(__solaris__)
 119 
 120     if (rv < 0)
 121         handleSocketError(env, errno);
 122 }
 123 
 124 JNIEXPORT jint JNICALL
 125 Java_sun_nio_ch_DatagramChannelImpl_receive0(JNIEnv *env, jobject this,
 126                                              jobject fdo, jlong address,
 127                                              jint len, jboolean connected)
 128 {
 129     jint fd = fdval(env, fdo);
 130     void *buf = (void *)jlong_to_ptr(address);
 131     SOCKETADDRESS sa;
 132     socklen_t sa_len = sizeof(SOCKETADDRESS);
 133     jboolean retry = JNI_FALSE;
 134     jint n = 0;
 135     jobject senderAddr;
 136 
 137     if (len > MAX_PACKET_LEN) {
 138         len = MAX_PACKET_LEN;
 139     }
 140 
 141     do {
 142         retry = JNI_FALSE;
 143         n = recvfrom(fd, buf, len, 0, &sa.sa, &sa_len);
 144         if (n < 0) {
 145             if (errno == EAGAIN || errno == EWOULDBLOCK) {
 146                 return IOS_UNAVAILABLE;
 147             }
 148             if (errno == EINTR) {
 149                 return IOS_INTERRUPTED;
 150             }
 151             if (errno == ECONNREFUSED) {
 152                 if (connected == JNI_FALSE) {
 153                     retry = JNI_TRUE;
 154                 } else {
 155                     JNU_ThrowByName(env, JNU_JAVANETPKG
 156                                     "PortUnreachableException", 0);
 157                     return IOS_THROWN;
 158                 }
 159             } else {
 160                 return handleSocketError(env, errno);
 161             }
 162         }
 163     } while (retry == JNI_TRUE);
 164 
 165     /*
 166      * If the source address and port match the cached address
 167      * and port in DatagramChannelImpl then we don't need to
 168      * create InetAddress and InetSocketAddress objects.
 169      */
 170     senderAddr = (*env)->GetObjectField(env, this, dci_senderAddrID);
 171     if (senderAddr != NULL) {
 172         if (!NET_SockaddrEqualsInetAddress(env, &sa, senderAddr)) {
 173             senderAddr = NULL;
 174         } else {
 175             jint port = (*env)->GetIntField(env, this, dci_senderPortID);
 176             if (port != NET_GetPortFromSockaddr(&sa)) {
 177                 senderAddr = NULL;
 178             }
 179         }
 180     }
 181     if (senderAddr == NULL) {
 182         jobject isa = NULL;
 183         int port = 0;
 184         jobject ia = NET_SockaddrToInetAddress(env, &sa, &port);
 185         if (ia != NULL) {
 186             isa = (*env)->NewObject(env, isa_class, isa_ctorID, ia, port);
 187         }
 188         CHECK_NULL_RETURN(isa, IOS_THROWN);
 189 
 190         (*env)->SetObjectField(env, this, dci_senderAddrID, ia);
 191         (*env)->SetIntField(env, this, dci_senderPortID,
 192                             NET_GetPortFromSockaddr(&sa));
 193         (*env)->SetObjectField(env, this, dci_senderID, isa);
 194     }
 195     return n;
 196 }
 197 
 198 JNIEXPORT jint JNICALL
 199 Java_sun_nio_ch_DatagramChannelImpl_send0(JNIEnv *env, jobject this,
 200                                           jboolean preferIPv6, jobject fdo, jlong address,
 201                                           jint len, jobject destAddress, jint destPort)
 202 {
 203     jint fd = fdval(env, fdo);
 204     void *buf = (void *)jlong_to_ptr(address);
 205     SOCKETADDRESS sa;
 206     int sa_len = 0;
 207     jint n = 0;
 208 
 209     if (len > MAX_PACKET_LEN) {
 210         len = MAX_PACKET_LEN;
 211     }
 212 
 213     if (NET_InetAddressToSockaddr(env, destAddress, destPort, &sa,
 214                                   &sa_len, preferIPv6) != 0) {
 215       return IOS_THROWN;
 216     }
 217 
 218     n = sendto(fd, buf, len, 0, &sa.sa, sa_len);
 219     if (n < 0) {
 220         if (errno == EAGAIN || errno == EWOULDBLOCK) {
 221             return IOS_UNAVAILABLE;
 222         }
 223         if (errno == EINTR) {
 224             return IOS_INTERRUPTED;
 225         }
 226         if (errno == ECONNREFUSED) {
 227             JNU_ThrowByName(env, JNU_JAVANETPKG "PortUnreachableException", 0);
 228             return IOS_THROWN;
 229         }
 230         return handleSocketError(env, errno);
 231     }
 232     return n;
 233 }