Branch: refs/heads/main Home: https://github.com/WebKit/WebKit Commit: 5aa25a106be747000c280a1e55134b906f9ffc41 https://github.com/WebKit/WebKit/commit/5aa25a106be747000c280a1e55134b906f9ffc41 Author: Alex Christensen <achristen...@apple.com> Date: 2023-05-29 (Mon, 29 May 2023)
Changed paths: M Source/WebCore/platform/network/DNS.cpp M Source/WebCore/platform/network/DNS.h M Source/WebCore/platform/network/cf/DNSResolveQueueCFNet.cpp Log Message: ----------- DNS lookup should request then wait for IPv4 and IPv6 addresses https://bugs.webkit.org/show_bug.cgi?id=257404 rdar://109911384 Reviewed by Youenn Fablet. As advised by one who knows DNS better than I do, with the code I wrote earlier today in https://github.com/WebKit/WebKit/pull/14326 I am missing some of the IP addresses. To receive a set of IP addresses equivalent to what CFHost received, I need to add the kDNSServiceFlagsReturnIntermediates flag. Also, there are some times when we receive IPv4 addresses then get a callback with kDNSServiceFlagsMoreComing and then sometime later receive IPv6 addresses, or vice versa. The addresses from the second set of callbacks were being dropped. To fix this, I explicitly add the protocols kDNSServiceProtocol_IPv4 | kDNSServiceProtocol_IPv6 to request callbacks for both protocols. This makes it so that sometimes I get callbacks with kDNSServiceErr_NoSuchRecord and callbacks with IP addresses that are all zeros. We simiply ignore kDNSServiceErr_NoSuchRecord and filter out all the all-zero IP addresses. That way the result of DNSResolveQueueCFNet::performDNSLookup always contains all the IP addresses. I manually verified that IP address lists were incomplete sometimes before this change, and now they are complete all the time. There are also two unit tests that exercise this code path, webrtc/datachannel/mdns-ice-candidates.html and TestWebKitAPI.WebKit2.RTCDataChannelPostMessage and I verified that they both pass. * Source/WebCore/platform/network/DNS.cpp: (WebCore::IPAddress::isAllZeros const): * Source/WebCore/platform/network/DNS.h: * Source/WebCore/platform/network/cf/DNSResolveQueueCFNet.cpp: (WebCore::DNSResolveQueueCFNet::CompletionHandlerWrapper::complete): (WebCore::DNSResolveQueueCFNet::CompletionHandlerWrapper::addIPAddress): (WebCore::DNSResolveQueueCFNet::CompletionHandlerWrapper::shouldWaitForMoreAddresses const): (WebCore::DNSResolveQueueCFNet::CompletionHandlerWrapper::filterZeroAddresses): (WebCore::dnsLookupCallback): (WebCore::DNSResolveQueueCFNet::performDNSLookup): Canonical link: https://commits.webkit.org/264655@main _______________________________________________ webkit-changes mailing list webkit-changes@lists.webkit.org https://lists.webkit.org/mailman/listinfo/webkit-changes