andreacavalli/netty5
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Ignore inline comments when parsing nameservers (#9894)

Browse Source 
Motivation:

The resolv.conf file may contain inline comments which should be ignored

Modifications:

- Detect if we have a comment after the ipaddress and if so skip it
- Add unit test

Result:

Fixes https://github.com/netty/netty/issues/9889
This commit is contained in:
Norman Maurer 2019-12-18 21:07:23 +01:00
parent 607cf801d2
commit 7931501769
3 changed files with 44 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
common/src/main/java/io/netty/util/internal/StringUtil.java
View File

@ -543,7 +543,7 @@ public final class StringUtil {
*
* @param seq The string to search.
* @param offset The offset to start searching at.
* @return the index of the first non-white space character or <{@code 0} if none was found.
* @return the index of the first non-white space character or <{@code -1} if none was found.
*/
public static int indexOfNonWhiteSpace(CharSequence seq, int offset) {
for (; offset < seq.length(); ++offset) {
@ -554,6 +554,22 @@ public final class StringUtil {
return -1;
}
/**
* Find the index of the first white space character in {@code s} starting at {@code offset}.
*
* @param seq The string to search.
* @param offset The offset to start searching at.
* @return the index of the first white space character or &lt;{@code -1} if none was found.
*/
public static int indexOfWhiteSpace(CharSequence seq, int offset) {
for (; offset < seq.length(); ++offset) {
if (Character.isWhitespace(seq.charAt(offset))) {
return offset;
}
}
return -1;
}
/**
* Determine if {@code c} lies within the range of values defined for
* <a href="http://unicode.org/glossary/#surrogate_code_point">Surrogate Code Point</a>.

17
resolver-dns/src/main/java/io/netty/resolver/dns/UnixResolverDnsServerAddressStreamProvider.java
View File

@ -36,6 +36,8 @@ import java.util.regex.Pattern;
import static io.netty.resolver.dns.DefaultDnsServerAddressStreamProvider.DNS_PORT;
import static io.netty.util.internal.StringUtil.indexOfNonWhiteSpace;
import static io.netty.util.internal.StringUtil.indexOfWhiteSpace;
import static java.util.Objects.requireNonNull;
/**
@ -179,7 +181,20 @@ public final class UnixResolverDnsServerAddressStreamProvider implements DnsServ
" in file " + etcResolverFile + ". value: " + line);
}
String maybeIP = line.substring(i);
String maybeIP;
int x = indexOfWhiteSpace(line, i);
if (x == -1) {
maybeIP = line.substring(i);
} else {
// ignore comments
int idx = indexOfNonWhiteSpace(line, x);
if (idx == -1 || line.charAt(idx) != '#') {
throw new IllegalArgumentException("error parsing label " + NAMESERVER_ROW_LABEL +
" in file " + etcResolverFile + ". value: " + line);
}
maybeIP = line.substring(i, x);
}
// There may be a port appended onto the IP address so we attempt to extract it.
if (!NetUtil.isValidIpV4Address(maybeIP) && !NetUtil.isValidIpV6Address(maybeIP)) {
i = maybeIP.lastIndexOf('.');

11
resolver-dns/src/test/java/io/netty/resolver/dns/UnixResolverDnsServerAddressStreamProviderTest.java
View File

@ -188,6 +188,17 @@ public class UnixResolverDnsServerAddressStreamProviderTest {
return f;
}
@Test
public void ignoreComments() throws Exception {
File f = buildFile("domain linecorp.local\n" +
"nameserver 127.0.0.2 #somecomment\n");
UnixResolverDnsServerAddressStreamProvider p =
new UnixResolverDnsServerAddressStreamProvider(f, null);
DnsServerAddressStream stream = p.nameServerAddressStream("somehost");
assertHostNameEquals("127.0.0.2", stream.next());
}
private static void assertHostNameEquals(String expectedHostname, InetSocketAddress next) {
assertEquals("unexpected hostname: " + next, expectedHostname, next.getHostString());
}