1 /*
2 * Copyright (c) 2001, 2012, 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 #include <io.h>
31 #include "sun_nio_ch_DatagramChannelImpl.h"
32 #include "nio.h"
33 #include "nio_util.h"
34 #include "net_util.h"
35 #include <winsock2.h>
36
37 static jfieldID dci_senderID; /* sender in sun.nio.ch.DatagramChannelImpl */
38 static jfieldID dci_senderAddrID; /* sender InetAddress in sun.nio.ch.DatagramChannelImpl */
39 static jfieldID dci_senderPortID; /* sender port in sun.nio.ch.DatagramChannelImpl */
40 static jclass isa_class; /* java.net.InetSocketAddress */
41 static jmethodID isa_ctorID; /* java.net.InetSocketAddress(InetAddress, int) */
42
43
44 JNIEXPORT void JNICALL
45 Java_sun_nio_ch_DatagramChannelImpl_initIDs(JNIEnv *env, jclass clazz)
46 {
47 clazz = (*env)->FindClass(env, "java/net/InetSocketAddress");
48 CHECK_NULL(clazz);
49 isa_class = (*env)->NewGlobalRef(env, clazz);
50 if (isa_class == NULL) {
51 JNU_ThrowOutOfMemoryError(env, NULL);
52 return;
53 }
54 isa_ctorID = (*env)->GetMethodID(env, clazz, "<init>",
55 "(Ljava/net/InetAddress;I)V");
56 CHECK_NULL(isa_ctorID);
57
58 clazz = (*env)->FindClass(env, "sun/nio/ch/DatagramChannelImpl");
59 CHECK_NULL(clazz);
60 dci_senderID = (*env)->GetFieldID(env, clazz, "sender",
61 "Ljava/net/SocketAddress;");
62 CHECK_NULL(dci_senderID);
63 dci_senderAddrID = (*env)->GetFieldID(env, clazz,
64 "cachedSenderInetAddress",
65 "Ljava/net/InetAddress;");
66 CHECK_NULL(dci_senderAddrID);
67 dci_senderPortID = (*env)->GetFieldID(env, clazz,
68 "cachedSenderPort", "I");
69 CHECK_NULL(dci_senderPortID);
70 }
71
72 /*
73 * This function "purges" all outstanding ICMP port unreachable packets
74 * outstanding on a socket and returns JNI_TRUE if any ICMP messages
75 * have been purged. The rational for purging is to emulate normal BSD
76 * behaviour whereby receiving a "connection reset" status resets the
77 * socket.
78 */
79 jboolean purgeOutstandingICMP(JNIEnv *env, jclass clazz, jint fd)
80 {
81 jboolean got_icmp = JNI_FALSE;
82 char buf[1];
83 fd_set tbl;
84 struct timeval t = { 0, 0 };
85 SOCKETADDRESS sa;
86 int addrlen = sizeof(sa);
87
88 /*
89 * Peek at the queue to see if there is an ICMP port unreachable. If there
90 * is then receive it.
91 */
92 FD_ZERO(&tbl);
93 FD_SET((u_int)fd, &tbl);
94 while(1) {
95 if (select(/*ignored*/fd+1, &tbl, 0, 0, &t) <= 0) {
96 break;
97 }
98 if (recvfrom(fd, buf, 1, MSG_PEEK,
99 &sa.sa, &addrlen) != SOCKET_ERROR) {
100 break;
101 }
102 if (WSAGetLastError() != WSAECONNRESET) {
103 /* some other error - we don't care here */
104 break;
105 }
106
107 recvfrom(fd, buf, 1, 0, &sa.sa, &addrlen);
108 got_icmp = JNI_TRUE;
109 }
110
111 return got_icmp;
112 }
113
114 JNIEXPORT void JNICALL
115 Java_sun_nio_ch_DatagramChannelImpl_disconnect0(JNIEnv *env, jobject this,
116 jobject fdo, jboolean isIPv6)
117 {
118 jint fd = fdval(env, fdo);
119 int rv = 0;
120 SOCKETADDRESS sa;
121 int sa_len = sizeof(sa);
122
123 memset(&sa, 0, sa_len);
124
125 rv = connect((SOCKET)fd, &sa.sa, sa_len);
126 if (rv == SOCKET_ERROR) {
127 handleSocketError(env, WSAGetLastError());
128 } else {
129 /* Disable WSAECONNRESET errors as socket is no longer connected */
130 BOOL enable = FALSE;
131 DWORD bytesReturned = 0;
132 WSAIoctl((SOCKET)fd, SIO_UDP_CONNRESET, &enable, sizeof(enable),
133 NULL, 0, &bytesReturned, NULL, NULL);
134 }
135 }
136
137 JNIEXPORT jint JNICALL
138 Java_sun_nio_ch_DatagramChannelImpl_receive0(JNIEnv *env, jobject this,
139 jobject fdo, jlong address,
140 jint len, jboolean connected)
141 {
142 jint fd = fdval(env, fdo);
143 void *buf = (void *)jlong_to_ptr(address);
144 SOCKETADDRESS sa;
145 int sa_len = sizeof(sa);
146 BOOL retry = FALSE;
147 jint n;
148 jobject senderAddr;
149
150 do {
151 retry = FALSE;
152 n = recvfrom((SOCKET)fd,
153 (char *)buf,
154 len,
155 0,
156 &sa.sa,
157 &sa_len);
158
159 if (n == SOCKET_ERROR) {
160 int theErr = (jint)WSAGetLastError();
161 if (theErr == WSAEMSGSIZE) {
162 /* Spec says the rest of the data will be discarded... */
163 n = len;
164 } else if (theErr == WSAECONNRESET) {
165 purgeOutstandingICMP(env, this, fd);
166 if (connected == JNI_FALSE) {
167 retry = TRUE;
168 } else {
169 JNU_ThrowByName(env, JNU_JAVANETPKG "PortUnreachableException", 0);
170 return IOS_THROWN;
171 }
172 } else if (theErr == WSAEWOULDBLOCK) {
173 return IOS_UNAVAILABLE;
174 } else return handleSocketError(env, theErr);
175 } else if (n > 0) {
176 JVM_callNetworkReadBytes(env, n);
177 }
178 } while (retry);
179
180 /*
181 * If the source address and port match the cached address
182 * and port in DatagramChannelImpl then we don't need to
183 * create InetAddress and InetSocketAddress objects.
184 */
185 senderAddr = (*env)->GetObjectField(env, this, dci_senderAddrID);
186 if (senderAddr != NULL) {
187 if (!NET_SockaddrEqualsInetAddress(env, &sa, senderAddr)) {
188 senderAddr = NULL;
189 } else {
190 jint port = (*env)->GetIntField(env, this, dci_senderPortID);
191 if (port != NET_GetPortFromSockaddr(&sa)) {
192 senderAddr = NULL;
193 }
194 }
195 }
196 if (senderAddr == NULL) {
197 jobject isa = NULL;
198 int port;
199 jobject ia = NET_SockaddrToInetAddress(env, &sa, &port);
200 if (ia != NULL) {
201 isa = (*env)->NewObject(env, isa_class, isa_ctorID, ia, port);
202 }
203 CHECK_NULL_RETURN(isa, IOS_THROWN);
204
205 // update cachedSenderInetAddress/cachedSenderPort
206 (*env)->SetObjectField(env, this, dci_senderAddrID, ia);
207 (*env)->SetIntField(env, this, dci_senderPortID,
208 NET_GetPortFromSockaddr(&sa));
209 (*env)->SetObjectField(env, this, dci_senderID, isa);
210 }
211 return n;
212 }
213
214 JNIEXPORT jint JNICALL
215 Java_sun_nio_ch_DatagramChannelImpl_send0(JNIEnv *env, jobject this,
216 jboolean preferIPv6, jobject fdo,
217 jlong address, jint len,
218 jobject destAddress, jint destPort)
219 {
220 jint fd = fdval(env, fdo);
221 void *buf = (void *)jlong_to_ptr(address);
222 SOCKETADDRESS sa;
223 int sa_len = 0;
224 jint rv = 0;
225
226 if (NET_InetAddressToSockaddr(env, destAddress, destPort, &sa,
227 &sa_len, preferIPv6) != 0) {
228 return IOS_THROWN;
229 }
230
231 rv = sendto((SOCKET)fd, buf, len, 0, &sa.sa, sa_len);
232 if (rv == SOCKET_ERROR) {
233 int theErr = (jint)WSAGetLastError();
234 if (theErr == WSAEWOULDBLOCK) {
235 return IOS_UNAVAILABLE;
236 }
237 return handleSocketError(env, (jint)WSAGetLastError());
238 }
239
240 if (rv > 0) {
241 JVM_callFileWriteBytes(env, rv);
242 }
243
244 return rv;
245 }