1 /*
2 * Copyright (c) 2000, 2020, 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 #include <malloc.h>
26
27 #include "net_util.h"
28
29 #include "java_net_InetAddress.h"
30 #include "java_net_Inet4AddressImpl.h"
31
32 /*
33 * Inet4AddressImpl
34 */
35
36 /*
37 * Class: java_net_Inet4AddressImpl
38 * Method: getLocalHostName
39 * Signature: ()Ljava/lang/String;
40 */
41 JNIEXPORT jstring JNICALL
Java_java_net_Inet4AddressImpl_getLocalHostName(JNIEnv * env,jobject this)42 Java_java_net_Inet4AddressImpl_getLocalHostName(JNIEnv *env, jobject this) {
43 char hostname[256];
44
45 if (gethostname(hostname, sizeof(hostname)) == -1) {
46 strcpy(hostname, "localhost");
47 }
48 return JNU_NewStringPlatform(env, hostname);
49 }
50
51 /*
52 * Find an internet address for a given hostname. Note that this
53 * code only works for addresses of type INET. The translation
54 * of %d.%d.%d.%d to an address (int) occurs in java now, so the
55 * String "host" shouldn't be a %d.%d.%d.%d string. The only
56 * exception should be when any of the %d are out of range and
57 * we fallback to a lookup.
58 *
59 * Class: java_net_Inet4AddressImpl
60 * Method: lookupAllHostAddr
61 * Signature: (Ljava/lang/String;)[[B
62 */
63 JNIEXPORT jobjectArray JNICALL
Java_java_net_Inet4AddressImpl_lookupAllHostAddr(JNIEnv * env,jobject this,jstring host)64 Java_java_net_Inet4AddressImpl_lookupAllHostAddr(JNIEnv *env, jobject this,
65 jstring host) {
66 jobjectArray ret = NULL;
67 const char *hostname;
68 int error = 0;
69 struct addrinfo hints, *res = NULL, *resNew = NULL, *last = NULL,
70 *iterator;
71
72 initInetAddressIDs(env);
73 JNU_CHECK_EXCEPTION_RETURN(env, NULL);
74
75 if (IS_NULL(host)) {
76 JNU_ThrowNullPointerException(env, "host argument is null");
77 return NULL;
78 }
79 hostname = JNU_GetStringPlatformChars(env, host, JNI_FALSE);
80 CHECK_NULL_RETURN(hostname, NULL);
81
82 // try once, with our static buffer
83 memset(&hints, 0, sizeof(hints));
84 hints.ai_flags = AI_CANONNAME;
85 hints.ai_family = AF_INET;
86
87 error = getaddrinfo(hostname, NULL, &hints, &res);
88
89 if (error) {
90 // report error
91 NET_ThrowByNameWithLastError(env, "java/net/UnknownHostException",
92 hostname);
93 goto cleanupAndReturn;
94 } else {
95 int i = 0;
96 iterator = res;
97 while (iterator != NULL) {
98 // skip duplicates
99 int skip = 0;
100 struct addrinfo *iteratorNew = resNew;
101 while (iteratorNew != NULL) {
102 struct sockaddr_in *addr1, *addr2;
103 addr1 = (struct sockaddr_in *)iterator->ai_addr;
104 addr2 = (struct sockaddr_in *)iteratorNew->ai_addr;
105 if (addr1->sin_addr.s_addr == addr2->sin_addr.s_addr) {
106 skip = 1;
107 break;
108 }
109 iteratorNew = iteratorNew->ai_next;
110 }
111
112 if (!skip) {
113 struct addrinfo *next
114 = (struct addrinfo *)malloc(sizeof(struct addrinfo));
115 if (!next) {
116 JNU_ThrowOutOfMemoryError(env, "Native heap allocation failed");
117 ret = NULL;
118 goto cleanupAndReturn;
119 }
120 memcpy(next, iterator, sizeof(struct addrinfo));
121 next->ai_next = NULL;
122 if (resNew == NULL) {
123 resNew = next;
124 } else {
125 last->ai_next = next;
126 }
127 last = next;
128 i++;
129 }
130 iterator = iterator->ai_next;
131 }
132
133 // allocate array - at this point i contains the number of addresses
134 ret = (*env)->NewObjectArray(env, i, ia_class, NULL);
135 if (IS_NULL(ret)) {
136 goto cleanupAndReturn;
137 }
138
139 i = 0;
140 iterator = resNew;
141 while (iterator != NULL) {
142 jobject iaObj = (*env)->NewObject(env, ia4_class, ia4_ctrID);
143 if (IS_NULL(iaObj)) {
144 ret = NULL;
145 goto cleanupAndReturn;
146 }
147 setInetAddress_addr(env, iaObj, ntohl(((struct sockaddr_in *)
148 (iterator->ai_addr))->sin_addr.s_addr));
149 if ((*env)->ExceptionCheck(env))
150 goto cleanupAndReturn;
151 setInetAddress_hostName(env, iaObj, host);
152 if ((*env)->ExceptionCheck(env))
153 goto cleanupAndReturn;
154 (*env)->SetObjectArrayElement(env, ret, i++, iaObj);
155 iterator = iterator->ai_next;
156 }
157 }
158 cleanupAndReturn:
159 JNU_ReleaseStringPlatformChars(env, host, hostname);
160 while (resNew != NULL) {
161 last = resNew;
162 resNew = resNew->ai_next;
163 free(last);
164 }
165 if (res != NULL) {
166 freeaddrinfo(res);
167 }
168 return ret;
169 }
170
171 /*
172 * Class: java_net_Inet4AddressImpl
173 * Method: getHostByAddr
174 * Signature: ([B)Ljava/lang/String;
175 *
176 * Theoretically the UnknownHostException could be enriched with gai error
177 * information. But as it is silently ignored anyway, there's no need for this.
178 * It's only important that either a valid hostname is returned or an
179 * UnknownHostException is thrown.
180 */
181 JNIEXPORT jstring JNICALL
Java_java_net_Inet4AddressImpl_getHostByAddr(JNIEnv * env,jobject this,jbyteArray addrArray)182 Java_java_net_Inet4AddressImpl_getHostByAddr(JNIEnv *env, jobject this,
183 jbyteArray addrArray) {
184 jstring ret = NULL;
185 char host[NI_MAXHOST + 1];
186 jbyte caddr[4];
187 jint addr;
188 struct sockaddr_in sa;
189
190 // construct a sockaddr_in structure
191 memset((char *)&sa, 0, sizeof(struct sockaddr_in));
192 (*env)->GetByteArrayRegion(env, addrArray, 0, 4, caddr);
193 addr = ((caddr[0] << 24) & 0xff000000);
194 addr |= ((caddr[1] << 16) & 0xff0000);
195 addr |= ((caddr[2] << 8) & 0xff00);
196 addr |= (caddr[3] & 0xff);
197 sa.sin_addr.s_addr = htonl(addr);
198 sa.sin_family = AF_INET;
199
200 if (getnameinfo((struct sockaddr *)&sa, sizeof(struct sockaddr_in),
201 host, NI_MAXHOST, NULL, 0, NI_NAMEREQD)) {
202 JNU_ThrowByName(env, "java/net/UnknownHostException", NULL);
203 } else {
204 ret = (*env)->NewStringUTF(env, host);
205 if (ret == NULL) {
206 JNU_ThrowByName(env, "java/net/UnknownHostException", NULL);
207 }
208 }
209
210 return ret;
211 }
212
213 /**
214 * ping implementation using tcp port 7 (echo)
215 */
216 static jboolean
tcp_ping4(JNIEnv * env,SOCKETADDRESS * sa,SOCKETADDRESS * netif,jint timeout,jint ttl)217 tcp_ping4(JNIEnv *env, SOCKETADDRESS *sa, SOCKETADDRESS *netif, jint timeout,
218 jint ttl)
219 {
220 jint fd;
221 int connect_rv = -1;
222 WSAEVENT hEvent;
223
224 // open a TCP socket
225 fd = NET_Socket(AF_INET, SOCK_STREAM, 0);
226 if (fd == SOCKET_ERROR) {
227 // note: if you run out of fds, you may not be able to load
228 // the exception class, and get a NoClassDefFoundError instead.
229 NET_ThrowNew(env, WSAGetLastError(), "Can't create socket");
230 return JNI_FALSE;
231 }
232
233 // set TTL
234 if (ttl > 0) {
235 setsockopt(fd, IPPROTO_IP, IP_TTL, (const char *)&ttl, sizeof(ttl));
236 }
237
238 // A network interface was specified, so let's bind to it.
239 if (netif != NULL) {
240 if (bind(fd, &netif->sa, sizeof(struct sockaddr_in)) < 0) {
241 NET_ThrowNew(env, WSAGetLastError(), "Can't bind socket");
242 closesocket(fd);
243 return JNI_FALSE;
244 }
245 }
246
247 // Make the socket non blocking so we can use select/poll.
248 hEvent = WSACreateEvent();
249 WSAEventSelect(fd, hEvent, FD_READ|FD_CONNECT|FD_CLOSE);
250
251 sa->sa4.sin_port = htons(7); // echo port
252 connect_rv = connect(fd, &sa->sa, sizeof(struct sockaddr_in));
253
254 // connection established or refused immediately, either way it means
255 // we were able to reach the host!
256 if (connect_rv == 0 || WSAGetLastError() == WSAECONNREFUSED) {
257 WSACloseEvent(hEvent);
258 closesocket(fd);
259 return JNI_TRUE;
260 }
261
262 switch (WSAGetLastError()) {
263 case WSAEHOSTUNREACH: // Host Unreachable
264 case WSAENETUNREACH: // Network Unreachable
265 case WSAENETDOWN: // Network is down
266 case WSAEPFNOSUPPORT: // Protocol Family unsupported
267 WSACloseEvent(hEvent);
268 closesocket(fd);
269 return JNI_FALSE;
270 case WSAEWOULDBLOCK: // this is expected as we'll probably have to wait
271 break;
272 default:
273 NET_ThrowByNameWithLastError(env, JNU_JAVANETPKG "ConnectException",
274 "connect failed");
275 WSACloseEvent(hEvent);
276 closesocket(fd);
277 return JNI_FALSE;
278 }
279
280 timeout = NET_Wait(env, fd, NET_WAIT_CONNECT, timeout);
281 if (timeout >= 0) {
282 // connection has been established, check for error condition
283 int optlen = sizeof(connect_rv);
284 if (getsockopt(fd, SOL_SOCKET, SO_ERROR, (void *)&connect_rv,
285 &optlen) < 0)
286 {
287 connect_rv = WSAGetLastError();
288 }
289 if (connect_rv == 0 || connect_rv == WSAECONNREFUSED) {
290 WSACloseEvent(hEvent);
291 closesocket(fd);
292 return JNI_TRUE;
293 }
294 }
295 WSACloseEvent(hEvent);
296 closesocket(fd);
297 return JNI_FALSE;
298 }
299
300 /**
301 * ping implementation.
302 * Send a ICMP_ECHO_REQUEST packet every second until either the timeout
303 * expires or a answer is received.
304 * Returns true is an ECHO_REPLY is received, otherwise, false.
305 */
306 static jboolean
ping4(JNIEnv * env,HANDLE hIcmpFile,SOCKETADDRESS * sa,SOCKETADDRESS * netif,jint timeout)307 ping4(JNIEnv *env, HANDLE hIcmpFile, SOCKETADDRESS *sa,
308 SOCKETADDRESS *netif, jint timeout)
309 {
310 DWORD dwRetVal = 0;
311 char SendData[32] = {0};
312 LPVOID ReplyBuffer = NULL;
313 DWORD ReplySize = 0;
314 jboolean ret = JNI_FALSE;
315
316 // See https://msdn.microsoft.com/en-us/library/aa366050%28VS.85%29.aspx
317 // or https://msdn.microsoft.com/en-us/library/windows/desktop/aa366051%28v=vs.85%29.aspx
318 ReplySize = sizeof(ICMP_ECHO_REPLY) // The buffer should be large enough
319 // to hold at least one ICMP_ECHO_REPLY
320 // structure
321 + sizeof(SendData) // plus RequestSize bytes of data.
322 + 8; // This buffer should also be large enough
323 // to also hold 8 more bytes of data
324 // (the size of an ICMP error message)
325
326 ReplyBuffer = (VOID *)malloc(ReplySize);
327 if (ReplyBuffer == NULL) {
328 IcmpCloseHandle(hIcmpFile);
329 NET_ThrowNew(env, -1, "Unable to allocate memory");
330 return JNI_FALSE;
331 }
332
333 if (netif == NULL) {
334 dwRetVal = IcmpSendEcho(hIcmpFile, // HANDLE IcmpHandle,
335 sa->sa4.sin_addr.s_addr, // IPAddr DestinationAddress,
336 SendData, // LPVOID RequestData,
337 sizeof(SendData), // WORD RequestSize,
338 NULL, // PIP_OPTION_INFORMATION RequestOptions,
339 ReplyBuffer,// LPVOID ReplyBuffer,
340 ReplySize, // DWORD ReplySize,
341 // Note: IcmpSendEcho and its derivatives
342 // seem to have an undocumented minimum
343 // timeout of 1000ms below which the
344 // api behaves inconsistently.
345 (timeout < 1000) ? 1000 : timeout); // DWORD Timeout
346 } else {
347 dwRetVal = IcmpSendEcho2Ex(hIcmpFile, // HANDLE IcmpHandle,
348 NULL, // HANDLE Event
349 NULL, // PIO_APC_ROUTINE ApcRoutine
350 NULL, // ApcContext
351 netif->sa4.sin_addr.s_addr, // IPAddr SourceAddress,
352 sa->sa4.sin_addr.s_addr, // IPAddr DestinationAddress,
353 SendData, // LPVOID RequestData,
354 sizeof(SendData), // WORD RequestSize,
355 NULL, // PIP_OPTION_INFORMATION RequestOptions,
356 ReplyBuffer,// LPVOID ReplyBuffer,
357 ReplySize, // DWORD ReplySize,
358 (timeout < 1000) ? 1000 : timeout); // DWORD Timeout
359 }
360
361 if (dwRetVal == 0) { // if the call failed
362 TCHAR *buf = NULL;
363 DWORD n;
364 DWORD err = WSAGetLastError();
365 switch (err) {
366 case ERROR_NO_NETWORK:
367 case ERROR_NETWORK_UNREACHABLE:
368 case ERROR_HOST_UNREACHABLE:
369 case ERROR_PROTOCOL_UNREACHABLE:
370 case ERROR_PORT_UNREACHABLE:
371 case ERROR_REQUEST_ABORTED:
372 case ERROR_INCORRECT_ADDRESS:
373 case ERROR_HOST_DOWN:
374 case ERROR_INVALID_COMPUTERNAME:
375 case ERROR_INVALID_NETNAME:
376 case WSAEHOSTUNREACH: /* Host Unreachable */
377 case WSAENETUNREACH: /* Network Unreachable */
378 case WSAENETDOWN: /* Network is down */
379 case WSAEPFNOSUPPORT: /* Protocol Family unsupported */
380 case IP_REQ_TIMED_OUT:
381 break;
382 default:
383 n = FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |
384 FORMAT_MESSAGE_FROM_SYSTEM,
385 NULL, err, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
386 (LPTSTR)&buf, 0, NULL);
387 if (n > 3) {
388 // Drop final '.', CR, LF
389 if (buf[n - 1] == TEXT('\n')) n--;
390 if (buf[n - 1] == TEXT('\r')) n--;
391 if (buf[n - 1] == TEXT('.')) n--;
392 buf[n] = TEXT('\0');
393 }
394 NET_ThrowNew(env, err, buf);
395 LocalFree(buf);
396 break;
397 }
398 } else {
399 PICMP_ECHO_REPLY pEchoReply = (PICMP_ECHO_REPLY)ReplyBuffer;
400
401 // This is to take into account the undocumented minimum
402 // timeout mentioned in the IcmpSendEcho call above.
403 // We perform an extra check to make sure that our
404 // roundtrip time was less than our desired timeout
405 // for cases where that timeout is < 1000ms.
406 if (pEchoReply->Status == IP_SUCCESS &&
407 (int)pEchoReply->RoundTripTime <= timeout)
408 {
409 ret = JNI_TRUE;
410 }
411 }
412
413 free(ReplyBuffer);
414 IcmpCloseHandle(hIcmpFile);
415
416 return ret;
417 }
418
419 /*
420 * Class: java_net_Inet4AddressImpl
421 * Method: isReachable0
422 * Signature: ([bI[bI)Z
423 */
424 JNIEXPORT jboolean JNICALL
Java_java_net_Inet4AddressImpl_isReachable0(JNIEnv * env,jobject this,jbyteArray addrArray,jint timeout,jbyteArray ifArray,jint ttl)425 Java_java_net_Inet4AddressImpl_isReachable0(JNIEnv *env, jobject this,
426 jbyteArray addrArray, jint timeout,
427 jbyteArray ifArray, jint ttl)
428 {
429 jbyte caddr[4];
430 jint addr = 0, sz;
431 SOCKETADDRESS sa, inf, *netif = NULL;
432 HANDLE hIcmpFile;
433
434 // check if address array size is 4 (IPv4 address)
435 sz = (*env)->GetArrayLength(env, addrArray);
436 if (sz != 4) {
437 return JNI_FALSE;
438 }
439
440 // convert IP address from byte array to integer
441 memset((char *)caddr, 0, sizeof(caddr));
442 (*env)->GetByteArrayRegion(env, addrArray, 0, 4, caddr);
443 addr = ((caddr[0] << 24) & 0xff000000);
444 addr |= ((caddr[1] << 16) & 0xff0000);
445 addr |= ((caddr[2] << 8) & 0xff00);
446 addr |= (caddr[3] & 0xff);
447 memset((char *)&sa, 0, sizeof(SOCKETADDRESS));
448 sa.sa4.sin_addr.s_addr = htonl(addr);
449 sa.sa4.sin_family = AF_INET;
450
451 // If a network interface was specified, let's convert its address as well.
452 if (!(IS_NULL(ifArray))) {
453 memset((char *)caddr, 0, sizeof(caddr));
454 (*env)->GetByteArrayRegion(env, ifArray, 0, 4, caddr);
455 addr = ((caddr[0] << 24) & 0xff000000);
456 addr |= ((caddr[1] << 16) & 0xff0000);
457 addr |= ((caddr[2] << 8) & 0xff00);
458 addr |= (caddr[3] & 0xff);
459 memset((char *)&inf, 0, sizeof(SOCKETADDRESS));
460 inf.sa4.sin_addr.s_addr = htonl(addr);
461 inf.sa4.sin_family = AF_INET;
462 netif = &inf;
463 }
464
465 // Let's try to create an ICMP handle.
466 hIcmpFile = IcmpCreateFile();
467 if (hIcmpFile == INVALID_HANDLE_VALUE) {
468 int err = WSAGetLastError();
469 if (err == ERROR_ACCESS_DENIED) {
470 // fall back to TCP echo if access is denied to ICMP
471 return tcp_ping4(env, &sa, netif, timeout, ttl);
472 } else {
473 NET_ThrowNew(env, err, "Unable to create ICMP file handle");
474 return JNI_FALSE;
475 }
476 } else {
477 // It didn't fail, so we can use ICMP.
478 return ping4(env, hIcmpFile, &sa, netif, timeout);
479 }
480 }
481