deps: c-ares float, win ipv6 bad fec0 prefix

rvagg · BridgeAR · commit 34d125f16c77 · 2017-10-02T01:16:12.000-03:00
Was 72c5458: PR-URL: #5090 Reviewed-By: Fedor Indutny <fedor@indutny.com> Reimplemented for c-ares 1.13.0 PR-URL: #15378 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
diff --git a/deps/cares/src/ares_init.c b/deps/cares/src/ares_init.c
@@ -1196,6 +1196,11 @@ static int get_DNS_AdaptersAddresses(char **outptr)
       }
       else if (namesrvr.sa->sa_family == AF_INET6)
       {
+        /* Windows apparently always reports some IPv6 DNS servers that
+         * prefixed with fec0:0:0:ffff. These ususally do not point to
+         * working DNS servers, so we ignore them. */
+        if (strncmp(addresses[addressesIndex].text, "fec0:0:0:ffff:", 14) == 0)
+          continue;
         if (memcmp(&namesrvr.sa6->sin6_addr, &ares_in6addr_any,
                    sizeof(namesrvr.sa6->sin6_addr)) == 0)
           continue;

Original file line number	Diff line number	Diff line change
`@@ -1196,6 +1196,11 @@ static int get_DNS_AdaptersAddresses(char **outptr)`
`1196`	`1196`	`}`
`1197`	`1197`	`else if (namesrvr.sa->sa_family == AF_INET6)`
`1198`	`1198`	`{`
	`1199`	`+ /* Windows apparently always reports some IPv6 DNS servers that`
	`1200`	`+ * prefixed with fec0:0:0:ffff. These ususally do not point to`
	`1201`	`+ * working DNS servers, so we ignore them. */`
	`1202`	`+ if (strncmp(addresses[addressesIndex].text, "fec0:0:0:ffff:", 14) == 0)`
	`1203`	`+ continue;`
`1199`	`1204`	`if (memcmp(&namesrvr.sa6->sin6_addr, &ares_in6addr_any,`
`1200`	`1205`	`sizeof(namesrvr.sa6->sin6_addr)) == 0)`
`1201`	`1206`	`continue;`