net: manually resolve dns seed sources

theuni · theuni · commit a98cd1fc86ea · 2016-04-20T13:07:19.000-04:00
Note: Some seeds aren't actually returning an IP for their name entries, so
they're being added to addrman with a source of [::].

This commit shouldn't change that behavior, for better or worse.
diff --git a/src/net.cpp b/src/net.cpp
@@ -1454,7 +1454,15 @@ void ThreadDNSAddressSeed()
                     found++;
                 }
             }
-            addrman.Add(vAdd, CNetAddr(seed.name, true));
+            // TODO: The seed name resolve may fail, yielding an IP of [::], which results in
+            // addrman assigning the same source to results from different seeds.
+            // This should switch to a hard-coded stable dummy IP for each seed name, so that the
+            // resolve is not required at all.
+            if (!vIPs.empty()) {
+                CService seedSource;
+                Lookup(seed.name.c_str(), seedSource, 0, true);
+                addrman.Add(vAdd, seedSource);
+            }
         }
     }
 

Original file line number	Diff line number	Diff line change
`@@ -1454,7 +1454,15 @@ void ThreadDNSAddressSeed()`
`1454`	`1454`	`found++;`
`1455`	`1455`	`}`
`1456`	`1456`	`}`
`1457`		`- addrman.Add(vAdd, CNetAddr(seed.name, true));`
	`1457`	`+ // TODO: The seed name resolve may fail, yielding an IP of [::], which results in`
	`1458`	`+ // addrman assigning the same source to results from different seeds.`
	`1459`	`+ // This should switch to a hard-coded stable dummy IP for each seed name, so that the`
	`1460`	`+ // resolve is not required at all.`
	`1461`	`+ if (!vIPs.empty()) {`
	`1462`	`+ CService seedSource;`
	`1463`	`+ Lookup(seed.name.c_str(), seedSource, 0, true);`
	`1464`	`+ addrman.Add(vAdd, seedSource);`
	`1465`	`+ }`
`1458`	`1466`	`}`
`1459`	`1467`	`}`
`1460`	`1468`