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cushoncushon
committedSep 25, 2023
8313804: JDWP support for -Djava.net.preferIPv6Addresses=system
Reviewed-by: cjplummer, amenkov
1 parent afa4833 commit 9291b46

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2 files changed

+117
-19
lines changed

2 files changed

+117
-19
lines changed
 

‎src/jdk.jdwp.agent/share/native/libdt_socket/socketTransport.c

+51-10
Original file line numberDiff line numberDiff line change
@@ -727,11 +727,13 @@ socketTransport_startListening(jdwpTransportEnv* env, const char* address,
727727
return err;
728728
}
729729

730-
// Try to find bind address of preferred address family first.
731-
for (ai = addrInfo; ai != NULL; ai = ai->ai_next) {
732-
if (ai->ai_family == preferredAddressFamily) {
733-
listenAddr = ai;
734-
break;
730+
// Try to find bind address of preferred address family first (if java.net.preferIPv6Addresses != "system").
731+
if (preferredAddressFamily != AF_UNSPEC) {
732+
for (ai = addrInfo; ai != NULL; ai = ai->ai_next) {
733+
if (ai->ai_family == preferredAddressFamily) {
734+
listenAddr = ai;
735+
break;
736+
}
735737
}
736738
}
737739

@@ -743,9 +745,9 @@ socketTransport_startListening(jdwpTransportEnv* env, const char* address,
743745
// Binding to IN6ADDR_ANY allows to serve both IPv4 and IPv6 connections,
744746
// but binding to mapped INADDR_ANY (::ffff:0.0.0.0) allows to serve IPv4
745747
// connections only. Make sure that IN6ADDR_ANY is preferred over
746-
// mapped INADDR_ANY if preferredAddressFamily is AF_INET6 or not set.
748+
// mapped INADDR_ANY if preferIPv4Stack is false.
747749

748-
if (preferredAddressFamily != AF_INET) {
750+
if (!allowOnlyIPv4) {
749751
inet_pton(AF_INET6, "::ffff:0.0.0.0", &mappedAny);
750752

751753
if (isEqualIPv6Addr(listenAddr, mappedAny)) {
@@ -967,8 +969,10 @@ socketTransport_attach(jdwpTransportEnv* env, const char* addressString, jlong a
967969
return err;
968970
}
969971

970-
/* 1st pass - preferredAddressFamily (by default IPv4), 2nd pass - the rest */
971-
for (pass = 0; pass < 2 && socketFD < 0; pass++) {
972+
// 1st pass - preferredAddressFamily (by default IPv4), 2nd pass - the rest;
973+
// if java.net.preferIPv6Addresses == "system", only 2nd pass is needed
974+
pass = preferredAddressFamily != AF_UNSPEC ? 0 : 1;
975+
for (; pass < 2 && socketFD < 0; pass++) {
972976
for (ai = addrInfo; ai != NULL; ai = ai->ai_next) {
973977
if ((pass == 0 && ai->ai_family == preferredAddressFamily) ||
974978
(pass == 1 && ai->ai_family != preferredAddressFamily))
@@ -1305,6 +1309,43 @@ static int readBooleanSysProp(int *result, int trueValue, int falseValue,
13051309
return JNI_OK;
13061310
}
13071311

1312+
/*
1313+
* Reads java.net.preferIPv6Addresses system value, sets preferredAddressFamily to
1314+
* - AF_INET6 if the property is "true";
1315+
* - AF_INET if the property is "false".
1316+
* - AF_UNSPEC if the property is "system".
1317+
* Doesn't change preferredAddressFamily if the property is not set or failed to read.
1318+
*/
1319+
static int readPreferIPv6Addresses(JNIEnv* jniEnv,
1320+
jclass sysClass, jmethodID getPropMethod, const char *propName)
1321+
{
1322+
jstring value;
1323+
jstring name = (*jniEnv)->NewStringUTF(jniEnv, propName);
1324+
1325+
if (name == NULL) {
1326+
return JNI_ERR;
1327+
}
1328+
value = (jstring)(*jniEnv)->CallStaticObjectMethod(jniEnv, sysClass, getPropMethod, name);
1329+
if ((*jniEnv)->ExceptionCheck(jniEnv)) {
1330+
return JNI_ERR;
1331+
}
1332+
if (value != NULL) {
1333+
const char *theValue = (*jniEnv)->GetStringUTFChars(jniEnv, value, NULL);
1334+
if (theValue == NULL) {
1335+
return JNI_ERR;
1336+
}
1337+
if (strcmp(theValue, "true") == 0) {
1338+
preferredAddressFamily = AF_INET6;
1339+
} else if (strcmp(theValue, "false") == 0) {
1340+
preferredAddressFamily = AF_INET;
1341+
} else if (strcmp(theValue, "system") == 0) {
1342+
preferredAddressFamily = AF_UNSPEC;
1343+
}
1344+
(*jniEnv)->ReleaseStringUTFChars(jniEnv, value, theValue);
1345+
}
1346+
return JNI_OK;
1347+
}
1348+
13081349
JNIEXPORT jint JNICALL
13091350
jdwpTransport_OnLoad(JavaVM *vm, jdwpTransportCallback* cbTablePtr,
13101351
jint version, jdwpTransportEnv** env)
@@ -1362,7 +1403,7 @@ jdwpTransport_OnLoad(JavaVM *vm, jdwpTransportCallback* cbTablePtr,
13621403
}
13631404
readBooleanSysProp(&allowOnlyIPv4, 1, 0,
13641405
jniEnv, sysClass, getPropMethod, "java.net.preferIPv4Stack");
1365-
readBooleanSysProp(&preferredAddressFamily, AF_INET6, AF_INET,
1406+
readPreferIPv6Addresses(
13661407
jniEnv, sysClass, getPropMethod, "java.net.preferIPv6Addresses");
13671408
} while (0);
13681409

‎test/jdk/com/sun/jdi/JdwpNetProps.java

+66-9
Original file line numberDiff line numberDiff line change
@@ -36,15 +36,16 @@
3636
import java.util.LinkedList;
3737
import java.util.List;
3838
import java.util.Map;
39+
import java.util.Objects;
3940

4041
/*
4142
* @test
42-
* @bug 8184770
43+
* @bug 8184770 8313804
4344
* @summary Tests that JDWP agent honors jdk net properties
4445
* @library /test/lib
4546
*
4647
* @build HelloWorld JdwpNetProps
47-
* @run main/othervm JdwpNetProps
48+
* @run main/othervm -Djava.net.preferIPv6Addresses=system JdwpNetProps
4849
*/
4950
public class JdwpNetProps {
5051

@@ -60,33 +61,88 @@ public static void main(String[] args) throws Exception {
6061
}
6162
}
6263

64+
String preferIPv6Address = System.getProperty("java.net.preferIPv6Addresses");
65+
if (!Objects.equals(preferIPv6Address, "system")) {
66+
throw new AssertionError(
67+
"Expected -Djava.net.preferIPv6Address=system, was " + preferIPv6Address);
68+
}
69+
boolean systemPrefersIPv6 = addrs[0] instanceof Inet6Address;
70+
6371
if (ipv4Address != null) {
6472
new ListenTest("localhost", ipv4Address)
6573
.preferIPv4Stack(true)
6674
.run(TestResult.Success);
75+
new ListenTest("localhost", ipv4Address)
76+
.preferIPv4Stack(true)
77+
.preferIPv6Addresses("true")
78+
.run(TestResult.Success);
79+
new ListenTest("localhost", ipv4Address)
80+
.preferIPv4Stack(true)
81+
.preferIPv6Addresses("system")
82+
.run(TestResult.Success);
6783
new ListenTest("localhost", ipv4Address)
6884
.preferIPv4Stack(false)
6985
.run(TestResult.Success);
7086
if (ipv6Address != null) {
71-
// - only IPv4, so connection prom IPv6 should fail
87+
// - only IPv4, so connection from IPv6 should fail
7288
new ListenTest("localhost", ipv6Address)
7389
.preferIPv4Stack(true)
74-
.preferIPv6Addresses(true)
90+
.preferIPv6Addresses("true")
91+
.run(TestResult.AttachFailed);
92+
new ListenTest("localhost", ipv6Address)
93+
.preferIPv4Stack(true)
94+
.preferIPv6Addresses("system")
7595
.run(TestResult.AttachFailed);
7696
// - listen on IPv4
7797
new ListenTest("localhost", ipv6Address)
78-
.preferIPv6Addresses(false)
98+
.preferIPv6Addresses("false")
99+
.run(TestResult.AttachFailed);
100+
// - listen on IPv4 (preferIPv6Addresses defaults to false)
101+
new ListenTest("localhost", ipv6Address)
79102
.run(TestResult.AttachFailed);
80103
// - listen on IPv6
81104
new ListenTest("localhost", ipv6Address)
82-
.preferIPv6Addresses(true)
105+
.preferIPv6Addresses("true")
83106
.run(TestResult.Success);
107+
new ListenTest("localhost", ipv6Address)
108+
.preferIPv6Addresses("system")
109+
.run(systemPrefersIPv6 ? TestResult.Success : TestResult.AttachFailed);
110+
// - listen on IPv6, connect from IPv4
111+
new ListenTest("localhost", ipv4Address)
112+
.preferIPv4Stack(false)
113+
.preferIPv6Addresses("true")
114+
.run(TestResult.AttachFailed);
115+
// - listen on system preference, connect from IPv4
116+
new ListenTest("localhost", ipv4Address)
117+
.preferIPv4Stack(false)
118+
.preferIPv6Addresses("system")
119+
.run(systemPrefersIPv6 ? TestResult.AttachFailed : TestResult.Success);
84120
}
85121
} else {
122+
if (!systemPrefersIPv6) {
123+
throw new AssertionError("The system is IPv6-only, but systemPrefersIPv6 was unexpectedly false");
124+
}
125+
86126
// IPv6-only system - expected to fail on IPv4 address
87127
new ListenTest("localhost", ipv6Address)
88128
.preferIPv4Stack(true)
89129
.run(TestResult.ListenFailed);
130+
new ListenTest("localhost", ipv6Address)
131+
.preferIPv4Stack(true)
132+
.preferIPv6Addresses("system")
133+
.run(TestResult.ListenFailed);
134+
new ListenTest("localhost", ipv6Address)
135+
.preferIPv4Stack(true)
136+
.preferIPv6Addresses("true")
137+
.run(TestResult.ListenFailed);
138+
new ListenTest("localhost", ipv6Address)
139+
.run(TestResult.Success);
140+
new ListenTest("localhost", ipv6Address)
141+
.preferIPv6Addresses("system")
142+
.run(TestResult.Success);
143+
new ListenTest("localhost", ipv6Address)
144+
.preferIPv6Addresses("true")
145+
.run(TestResult.Success);
90146
}
91147
}
92148

@@ -100,7 +156,7 @@ private static class ListenTest {
100156
private final String listenAddress;
101157
private final InetAddress connectAddress;
102158
private Boolean preferIPv4Stack;
103-
private Boolean preferIPv6Addresses;
159+
private String preferIPv6Addresses;
104160
public ListenTest(String listenAddress, InetAddress connectAddress) {
105161
this.listenAddress = listenAddress;
106162
this.connectAddress = connectAddress;
@@ -109,7 +165,7 @@ public ListenTest preferIPv4Stack(Boolean value) {
109165
preferIPv4Stack = value;
110166
return this;
111167
}
112-
public ListenTest preferIPv6Addresses(Boolean value) {
168+
public ListenTest preferIPv6Addresses(String value) {
113169
preferIPv6Addresses = value;
114170
return this;
115171
}
@@ -120,7 +176,7 @@ public void run(TestResult expectedResult) throws Exception {
120176
options.add("-Djava.net.preferIPv4Stack=" + preferIPv4Stack.toString());
121177
}
122178
if (preferIPv6Addresses != null) {
123-
options.add("-Djava.net.preferIPv6Addresses=" + preferIPv6Addresses.toString());
179+
options.add("-Djava.net.preferIPv6Addresses=" + preferIPv6Addresses);
124180
}
125181
log("Starting listening debuggee at " + listenAddress
126182
+ (expectedResult == TestResult.ListenFailed ? ": expected to fail" : ""));
@@ -201,4 +257,5 @@ private static void log(Object o) {
201257
System.out.println(String.valueOf(o));
202258
}
203259

260+
204261
}

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