From afdc91f21fabc2fedd81d7c0b0529669d963f50b Mon Sep 17 00:00:00 2001
From: Travis LaDuke <travisladuke@gmail.com>
Date: Fri, 5 Nov 2021 08:02:10 -0700
Subject: [PATCH] Convince macOS to do ipv6 dns lookups
Puts a value into System Config, similar to how DNS push works.
closes #1466
https://apple.stackexchange.com/questions/309430/ipv6-dns-resolution-on-macos-high-sierra
---
osdep/MacDNSHelper.hpp | 3 +
osdep/MacDNSHelper.mm | 133 ++++++++++++++++++++++++++++++++++++++-
osdep/MacEthernetTap.cpp | 1 +
service/OneService.cpp | 5 ++
4 files changed, 141 insertions(+), 1 deletion(-)
diff --git a/osdep/MacDNSHelper.hpp b/osdep/MacDNSHelper.hpp
index 7a2902fa5..2fa283621 100644
--- a/osdep/MacDNSHelper.hpp
+++ b/osdep/MacDNSHelper.hpp
@@ -3,6 +3,7 @@
#include <vector>
#include "../node/InetAddress.hpp"
+#include "../node/MAC.hpp"
namespace ZeroTier {
@@ -11,6 +12,8 @@ class MacDNSHelper
public:
static void setDNS(uint64_t nwid, const char *domain, const std::vector<InetAddress> &servers);
static void removeDNS(uint64_t nwid);
+ static bool addIps(uint64_t nwid, const MAC mac, const char *dev, const std::vector<InetAddress> &addrs);
+ static bool removeIps(uint64_t nwid);
};
}
diff --git a/osdep/MacDNSHelper.mm b/osdep/MacDNSHelper.mm
index 38e74dc3f..8a5bebd92 100644
--- a/osdep/MacDNSHelper.mm
+++ b/osdep/MacDNSHelper.mm
@@ -6,6 +6,11 @@
namespace ZeroTier {
+static void printKeys (const void* key, const void* value, void* context) {
+ CFShow(key);
+ CFShow(value);
+}
+
void MacDNSHelper::setDNS(uint64_t nwid, const char *domain, const std::vector<InetAddress> &servers)
{
SCDynamicStoreRef ds = SCDynamicStoreCreate(NULL, CFSTR("zerotier"), NULL, NULL);
@@ -85,4 +90,130 @@ void MacDNSHelper::removeDNS(uint64_t nwid)
CFRelease(ds);
}
-}
\ No newline at end of file
+// Make macOS believe we do in fact have ipv6 connectivity and that it should resolve dns names
+// over ipv6 if we ask for them.
+// Originally I planned to put all the v6 ip addresses from the network into the config.
+// But only the link local address is necessary and sufficient. Added other v6 addresses
+// doesn't do anything.
+bool MacDNSHelper::addIps(uint64_t nwid, const MAC mac, const char *dev, const std::vector<InetAddress>& addrs)
+{
+
+ bool hasV6 = false;
+ for (unsigned int i = 0; i < addrs.size(); ++i) {
+ if (addrs[i].isV6()) {
+ hasV6 = true;
+ break;
+ }
+ }
+
+ if (!hasV6) {
+ MacDNSHelper::removeIps(nwid);
+ return true;
+ }
+
+
+ SCDynamicStoreRef ds = SCDynamicStoreCreate(NULL, CFSTR("zerotier"), NULL, NULL);
+ char buf[256] = { 0 };
+ sprintf(buf, "State:/Network/Service/%.16llx/IPv6", nwid);
+
+ InetAddress ll = InetAddress::makeIpv6LinkLocal(mac);
+ char buf2[256] = {0};
+ const char* llStr = ll.toIpString(buf2);
+
+
+ CFStringRef key = CFStringCreateWithCString(NULL, buf, kCFStringEncodingUTF8);
+ CFStringRef* cfaddrs = new CFStringRef[1];
+ CFStringRef* cfprefixes = new CFStringRef[1];
+ CFStringRef* cfdestaddrs = new CFStringRef[1];
+ CFStringRef* cfflags = new CFStringRef[1];
+
+
+ cfaddrs[0] = CFStringCreateWithCString(NULL, llStr, kCFStringEncodingUTF8);
+ cfprefixes[0] = CFStringCreateWithCString(NULL, "64", kCFStringEncodingUTF8);
+ cfdestaddrs[0] = CFStringCreateWithCString(NULL, "::ffff:ffff:ffff:ffff:0:0", kCFStringEncodingUTF8);
+ cfflags[0] = CFStringCreateWithCString(NULL, "0", kCFStringEncodingUTF8);
+
+ CFArrayRef addrArray = CFArrayCreate(NULL, (const void**)cfaddrs, 1, &kCFTypeArrayCallBacks);
+ CFArrayRef prefixArray = CFArrayCreate(NULL, (const void**)cfprefixes, 1, &kCFTypeArrayCallBacks);
+ CFArrayRef destArray = CFArrayCreate(NULL, (const void**)cfdestaddrs, 1, &kCFTypeArrayCallBacks);
+ CFArrayRef flagsArray = CFArrayCreate(NULL, (const void**)cfflags, 1, &kCFTypeArrayCallBacks);
+ CFStringRef cfdev = CFStringCreateWithCString(NULL, dev, kCFStringEncodingUTF8);
+
+ const int SIZE = 5;
+ CFStringRef keys[SIZE];
+ keys[0] = CFSTR("Addresses");
+ keys[1] = CFSTR("DestAddresses");
+ keys[2] = CFSTR("Flags");
+ keys[3] = CFSTR("InterfaceName");
+ keys[4] = CFSTR("PrefixLength");
+
+ CFTypeRef values[SIZE];
+ values[0] = addrArray;
+ values[1] = destArray;
+ values[2] = flagsArray;
+ // values[3] = devArray;
+ values[3] = cfdev;
+ values[4] = prefixArray;
+
+
+ CFDictionaryRef dict = CFDictionaryCreate(NULL,
+ (const void**)keys, (const void**)values, SIZE, &kCFCopyStringDictionaryKeyCallBacks,
+ &kCFTypeDictionaryValueCallBacks);
+
+ // CFDictionaryApplyFunction(dict, printKeys, NULL);
+
+ CFArrayRef list = SCDynamicStoreCopyKeyList(ds, key);
+ CFIndex i = 0, j = CFArrayGetCount(list);
+ bool addrsChanged = true;
+ CFPropertyListRef oldAddrs = NULL;
+
+ bool ret = TRUE;
+ if (j > 0) {
+ oldAddrs = SCDynamicStoreCopyValue(ds, (CFStringRef)CFArrayGetValueAtIndex(list, i));
+ addrsChanged = !CFEqual(oldAddrs,dict);
+ }
+ if (addrsChanged) {
+ if (j <= 0) {
+ ret &= SCDynamicStoreAddValue(ds, key, dict);
+ } else {
+ ret &= SCDynamicStoreSetValue(ds, (CFStringRef)CFArrayGetValueAtIndex(list, i), dict);
+ }
+ if (!ret) {
+ fprintf(stderr, "Error writing IPv6 configuration\n");
+ }
+ }
+
+ CFRelease(addrArray);
+ CFRelease(prefixArray);
+ CFRelease(destArray);
+ CFRelease(flagsArray);
+ CFRelease(cfdev);
+
+ CFRelease(list);
+ CFRelease(dict);
+
+ CFRelease(ds);
+ CFRelease(key);
+
+ delete[] cfaddrs;
+ delete[] cfprefixes;
+ delete[] cfdestaddrs;
+ delete[] cfflags;
+
+ return ret;
+}
+bool MacDNSHelper::removeIps(uint64_t nwid)
+{
+ SCDynamicStoreRef ds = SCDynamicStoreCreate(NULL, CFSTR("zerotier"), NULL, NULL);
+
+ char buf[256] = {0};
+ sprintf(buf, "State:/Network/Service/%.16llx/IPv6", nwid);
+ CFStringRef key = CFStringCreateWithCString(NULL, buf, kCFStringEncodingUTF8);
+ bool res = SCDynamicStoreRemoveValue(ds, key);
+ CFRelease(key);
+ CFRelease(ds);
+
+ return res;
+}
+
+}
diff --git a/osdep/MacEthernetTap.cpp b/osdep/MacEthernetTap.cpp
index 1ba82dcb7..55822fd5a 100644
--- a/osdep/MacEthernetTap.cpp
+++ b/osdep/MacEthernetTap.cpp
@@ -244,6 +244,7 @@ MacEthernetTap::~MacEthernetTap()
pid_t pid0,pid1;
MacDNSHelper::removeDNS(_nwid);
+ MacDNSHelper::removeIps(_nwid);
Mutex::Lock _gl(globalTapCreateLock);
::write(_shutdownSignalPipe[1],"\0",1); // causes thread to exit
diff --git a/service/OneService.cpp b/service/OneService.cpp
index 255bad21e..68891b8e5 100644
--- a/service/OneService.cpp
+++ b/service/OneService.cpp
@@ -2041,6 +2041,11 @@ public:
fprintf(stderr,"ERROR: unable to add ip address %s" ZT_EOL_S, ip->toString(ipbuf));
}
}
+
+#ifdef __APPLE__
+ if (!MacDNSHelper::addIps(n.config.nwid, n.config.mac, n.tap->deviceName().c_str(), newManagedIps))
+ fprintf(stderr, "ERROR: unable to add v6 addresses to system configuration" ZT_EOL_S);
+#endif
#endif
n.managedIps.swap(newManagedIps);
}