more precise naming

packet_info.nim

@@ -47,7 +47,7 @@ type
     tcp
     other
 
-  PacketInfo* = object
+  IpPacket* = object
     case protocol*: Protocol
     of tcp:
       tcpIpSrc*: string
@@ -62,21 +62,21 @@ var
   ETHERTYPE_IP {.importc: "ETHERTYPE_IP", header: "<netinet/if_ether.h>".}: cushort
   IPPROTO_TCP {.importc: "IPPROTO_TCP", header: "<netinet/in.h>".}: cint
 
-proc fromString*(packet: string): PacketInfo =
-  let etherHeader = cast[ptr Ether_header](packet.cstring)
+proc parseEthernetPacket*(input: string): IpPacket =
+  let etherHeader = cast[ptr Ether_header](input.cstring)
   if ntohs(etherHeader.ether_type) == ETHERTYPE_IP:
-    let ipHeader = cast[ptr Ip](cast[int](packet.cstring) + sizeof(Ether_header))
+    let ipHeader = cast[ptr Ip](cast[int](input.cstring) + sizeof(Ether_header))
     let ipSrc = $inet_ntoa(ipHeader.ip_src)
     let ipDst = $inet_ntoa(ipHeader.ip_dst)
     if ipHeader.ip_p.int == IPPROTO_TCP:
       let tcpHeader = cast[ptr Tcphdr](cast[int](ipHeader) + ipHeader.ip_hl.int * 4)
-      result = PacketInfo(protocol: tcp,
-                          tcpIpSrc: ipSrc,
-                          tcpIpDst: ipDst,
-                          tcpPortSrc: Port(ntohs(tcpHeader.th_sport)),
-                          tcpPortDst: Port(ntohs(tcpHeader.th_dport)),
-                          tcpSeqNumber: ntohl(tcpHeader.th_seq))
+      result = IpPacket(protocol: tcp,
+                      tcpIpSrc: ipSrc,
+                      tcpIpDst: ipDst,
+                      tcpPortSrc: Port(ntohs(tcpHeader.th_sport)),
+                      tcpPortDst: Port(ntohs(tcpHeader.th_dport)),
+                      tcpSeqNumber: ntohl(tcpHeader.th_seq))
     else:
-      result = PacketInfo(protocol: other)
+      result = IpPacket(protocol: other)
   else:
-    result = PacketInfo(protocol: other)
+    result = IpPacket(protocol: other)

raw_socket.nim

@@ -30,7 +30,7 @@ var
   PACKET_ADD_MEMBERSHIP {.importc: "PACKET_ADD_MEMBERSHIP", header: "<linux/if_packet.h>".}: cushort
   PACKET_MR_PROMISC {.importc: "PACKET_MR_PROMISC", header: "<linux/if_packet.h>".}: cushort
 
-proc setupRawSocket*(iface: NetworkInterface): AsyncFD =
+proc setupEthernetCapturingSocket*(iface: NetworkInterface): AsyncFD =
   # Create a raw packet socket. For accessing outgoing packets we need to use
   # ETH_P_ALL which is needed in network byte order, see packet(7) man page.
   result = createAsyncNativeSocket(AF_PACKET.cint,

tcp_syni.nim

@@ -66,14 +66,14 @@ proc captureSeqNumbers(puncher: TcpSyniPuncher, rawFd: AsyncFD,
     if packet == "":
       break
     echo "packet len: ", packet.len
-    let packetInfo = fromString(packet)
-    if packetInfo.protocol == tcp and
-       packetInfo.tcpIpSrc == $puncher.srcIp and
-       packetInfo.tcpPortSrc.int == puncher.srcPort.int and
-       packetInfo.tcpIpDst == $puncher.dstIp:
+    let parsed = parseEthernetPacket(packet)
+    if parsed.protocol == tcp and
+       parsed.tcpIpSrc == $puncher.srcIp and
+       parsed.tcpPortSrc.int == puncher.srcPort.int and
+       parsed.tcpIpDst == $puncher.dstIp:
       for i, port in puncher.dstPorts.pairs:
-        if packetInfo.tcpPortDst.int == port.int:
-          seqNums.add(packetInfo.tcpSeqNumber)
+        if parsed.tcpPortDst.int == port.int:
+          seqNums.add(parsed.tcpSeqNumber)
           break
   await cb(seqNums)
 
@@ -111,7 +111,7 @@ proc connect*(puncher: TcpSyniPuncher,
               progressCb: PunchProgressCb): Future[AsyncSocket] =
   result = newFuture[AsyncSocket]("tcp_syni.connect")
   let iface = fromIpAddress($puncher.srcIp)
-  let rawFd = setupRawSocket(iface)
+  let rawFd = setupEthernetCapturingSocket(iface)
   asyncCheck puncher.captureSeqNumbers(rawFd, progressCb)
   for dstPort in puncher.dstPorts:
     asyncCheck doConnect(puncher.srcIp, puncher.srcPort, puncher.dstIp,