diff --git a/network_interface.nim b/network_interface.nim
index 8fd38b1..c383d5f 100644
--- a/network_interface.nim
+++ b/network_interface.nim
@@ -1,10 +1,11 @@
 from nativesockets import getAddrString
-from posix import SockAddr, Sockaddr_in, inet_ntoa, AF_INET
+from net import IpAddress, parseIpAddress, `$`
+from posix import SockAddr, AF_INET, AF_INET6
 
 type
   NetworkInterface* = object
-    ipAddress*: string
-    netMask*: string
+    ipAddress*: IpAddress
+    netMask*: IpAddress
     name*: string
     index*: cint
     flags*: cuint
@@ -25,17 +26,18 @@ proc getifaddrs(ifap: ptr ptr Ifaddrs): int {.header: "<ifaddrs.h>", importc: "g
 proc freeifaddrs(ifap: ptr Ifaddrs): void {.header: "<ifaddrs.h>", importc: "freeifaddrs".}
 proc if_nametoindex(ifname: cstring): cuint {.header: "<net/if.h>", importc: "if_nametoindex".}
 
-proc fromIpAddress*(address: string): NetworkInterface =
+proc fromIpAddress*(address: IpAddress): NetworkInterface =
   var interfaces: ptr Ifaddrs
   if getifaddrs(addr interfaces) != 0:
     raise newException(NetworkInterfaceError, "getifaddrs failed")
   var it = interfaces
   while it != nil:
     if it.ifa_addr != nil and
-       it.ifa_addr.sa_family.cint == AF_INET and
-       it.ifa_addr.getAddrString() == address:
+       (it.ifa_addr.sa_family.cint == AF_INET  or
+        it.ifa_addr.sa_family.cint == AF_INET6) and
+       $address == it.ifa_addr.getAddrString():
       result.ipAddress = address
-      result.netMask = it.ifa_netmask.getAddrString()
+      result.netMask = parseIpAddress(it.ifa_addr.getAddrString())
       result.name = $it.ifa_name
       result.index = if_nametoindex(result.name).cint
       result.flags = it.ifa_flags
diff --git a/tcp_syni.nim b/tcp_syni.nim
index 5a9804f..01335c5 100644
--- a/tcp_syni.nim
+++ b/tcp_syni.nim
@@ -167,7 +167,7 @@ proc doAccept(puncher: TcpSyniPuncher, future: Future[AsyncSocket]) {.async.} =
 proc connect*(puncher: TcpSyniPuncher,
               progressCb: PunchProgressCb): Future[AsyncSocket] =
   result = newFuture[AsyncSocket]("tcp_syni.connect")
-  let iface = fromIpAddress($puncher.srcIp)
+  let iface = fromIpAddress(puncher.srcIp)
   let rawFd = setupEthernetCapturingSocket(iface)
   asyncCheck puncher.captureSeqNumbers(rawFd, progressCb)
   for dstPort in puncher.dstPorts: