pcapwrap.nim

import posix
import strutils

when defined(macosx):
  const
    libName = "libpcap.dylib"
    defaultIfName* = "en0"
else:
  # where is u_int type defined for pcap.h??

  const
    libName = "libpcap.so"
    defaultIfName* = "eth0"

const
  PCAP_ERRBUF_SIZE* = 256
  PCAP_NETMASK_UNKNOWN* = 0xffffffff.uint32

type
  pcap_t* {.importc: "pcap_t", header: "<pcap/pcap.h>".} = object
  
  pcap_pkthdr* {.importc: "struct pcap_pkthdr", header: "<pcap/pcap.h>",
  final, pure.} = object
    ts*{.importc.}: Timeval
    caplen*{.importc.}: uint32
    len*{.importc.}: uint32

  pcap_stat* {.importc: "struct pcap_stat", header: "<pcap/pcap.h>", final, pure.} = object
    when defined(macosx):
      ps_recv*{.importc.}: uint32
      ps_drop*{.importc.}: uint32
      ps_ifdrop*{.importc.}: uint32
    else:
      ps_capt*{.importc.}: uint32
      ps_sent*{.importc.}: uint32
      ps_netdrop*{.importc.}: uint32

  bpf_insn* {.importc: "struct bpf_insn", header: "<pcap/bpf.h>", final, pure.} = object
    code*{.importc.}: uint16
    jt*{.importc.}: cstring
    jf*{.importc.}:  cstring
    k*{.importc.}: uint32

  bpf_program* {.importc: "struct bpf_program", header: "<pcap/bpf.h>", final, pure.} = object
    bf_len*{.importc.}: uint32
    bf_insns*{.importc.}: bpf_insn

  link_layers* = enum
    LINKTYPE_NULL = 0
    LINKTYPE_ETHERNET
    LINKTYPE_AX25
    LINKTYPE_IEEE802_5
    LINKTYPE_ARCNET_BSD
    LINKTYPE_SLIP
    LINKTYPE_PPP
    LINKTYPE_FDDI
    LINKTYPE_PPP_HDLC
    LINKTYPE_PPP_ETHER
    LINKTYPE_ATM_RFC1483
    LINKTYPE_RAW
    LINKTYPE_C_HDLC
    LINKTYPE_IEEE802_11
    LINKTYPE_FRELAY
    LINKTYPE_LOOP
    LINKTYPE_LINUX_SLL
    LINKTYPE_LTALK
    LINKTYPE_PFLOG
    LINKTYPE_IEEE802_11_PRISM
    LINKTYPE_IP_OVER_FC
    LINKTYPE_SUNATM
    LINKTYPE_IEEE802_11_RADIOTAP
    LINKTYPE_ARCNET_LINUX
    LINKTYPE_APPLE_IP_OVER_IEEE1394
    LINKTYPE_MTP2_WITH_PHDR
    LINKTYPE_MTP2
    LINKTYPE_MTP3
    LINKTYPE_SCCP
    LINKTYPE_DOCSIS
    LINKTYPE_LINUX_IRDA = 144
    LINKTYPE_IEEE802_11_AVS = 163
    LINKTYPE_BACNET_MS_TP
    LINKTYPE_PPP_PPPD
    LINKTYPE_GPRS_LLC
    LINKTYPE_GPF_T
    LINKTYPE_GPF_F
    LINKTYPE_LINUX_LAPD
    LINKTYPE_MFR
    LINKTYPE_BLUETOOTH_HCI_H4
    LINKTYPE_USB_LINUX
    LINKTYPE_PPI
    LINKTYPE_IEEE802_15_4_WITHFCS
    LINKTYPE_SITA
    LINKTYPE_ERF
    LINKTYPE_BLUETOOTH_HCI_H4_WITH_PHDR
    LINKTYPE_AX25_KISS
    LINKTYPE_LAPD
    LINKTYPE_PPP_WITH_DIR
    LINKTYPE_C_HDLC_WITH_DIR
    LINKTYPE_FRELAY_WITH_DIR
    LINKTYPE_LAPB_WITH_DIR
    LINKTYPE_IPMB_LINUX
    LINKTYPE_IEEE802_15_4_NONASK_PHY
    LINKTYPE_USB_LINUX_MMAPPED
    LINKTYPE_FC_2
    LINKTYPE_FC_2_WITH_FRAME_DELIMS
    LINKTYPE_IPNET
    LINKTYPE_CAN_SOCKETCAN
    LINKTYPE_IPV4
    LINKTYPE_IPV6
    LINKTYPE_IEEE802_15_4_NOFCS
    LINKTYPE_DBUS
    LINKTYPE_DVB_CI
    LINKTYPE_MUX27010
    LINKTYPE_STANAG_5066_D_PDU
    LINKTYPE_NFLOG
    LINKTYPE_NETANALYZER
    LINKTYPE_NETANALYZER_TRANSPARENT
    LINKTYPE_IPOIB
    LINKTYPE_MPEG_2_TS
    LINKTYPE_NG40
    LINKTYPE_NFC_LLCP
    LINKTYPE_INFINIBAND
    LINKTYPE_SCTP
    LINKTYPE_USBPCAP
    LINKTYPE_RTAC_SERIAL
    LINKTYPE_BLUETOOTH_LE_LL
    LINKTYPE_NETLINK
    LINKTYPE_BLUETOOTH_LINUX_MONITOR
    LINKTYPE_BLUETOOTH_BREDR_BB
    LINKTYPE_BLUETOOTH_LE_LL_WITH_PHDR
    LINKTYPE_PROFIBUS_DL
    LINKTYPE_PKTAP
    LINKTYPE_EPON
    LINKTYPE_IPMI_HPM_2
    LINKTYPE_ZWAVE_R1_R2
    LINKTYPE_ZWAVE_R3
    LINKTYPE_WATTSTOPPER_DLM
    LINKTYPE_ISO_14443
    LINKTYPE_RDS
    LINKTYPE_USB_DARWIN
    LINKTYPE_SDLC
    LINKTYPE_LORATAP
    LINKTYPE_VSOCK
    LINKTYPE_NORDIC_BLE
    LINKTYPE_DOCSIS31_XRA31
    LINKTYPE_ETHERNET_MPACKET
    LINKTYPE_DISPLAYPORT_AUX
    LINKTYPE_LINUX_SLL2
    LINKTYPE_OPENVIZSLA
    LINKTYPE_EBHSCR
    LINKTYPE_VPP_DISPATCH
    LINKTYPE_DSA_TAG_BRCM
    LINKTYPE_DSA_TAG_BRCM_PREPEND
    LINKTYPE_IEEE802_15_4_TAP
    LINKTYPE_DSA_TAG_DSA
    LINKTYPE_DSA_TAG_EDSA


proc pcap_close*(pcap: ptr pcap_t)
  {.cdecl, dynlib: libName, importc.}

proc pcap_next*(pcap: ptr pcap_t, pcappkthdr: ptr pcap_pkthdr): cstring
  {.cdecl, dynlib: libName, importc.}

proc pcap_next_ex*(pcap: ptr pcap_t, pcappktthdr: ptr ptr pcap_pkthdr, c: ptr cuchar): cint
  {.cdecl, dynlib: libName, importc.}

proc pcap_stats*(pcap: ptr pcap_t, pstats: ptr pcap_stat): cint
  {.cdecl, dynlib: libName, importc.}

proc pcap_setfilter*(pcap: ptr pcap_t, bpfprogram: ptr bpf_program): cint
  {.cdecl, dynlib: libName, importc.}

proc pcap_compile*(pcap: ptr pcap_t, fp: ptr bpf_program, str: cstring, optimize: cint, netmask: uint): cint
  {.cdecl, dynlib: libName, importc.}

proc pcap_getnonblock*(pcap: ptr pcap_t, str: cstring): cint
  {.cdecl, dynlib: libName, importc.}

proc pcap_sendpacket*(pcap: ptr pcap_t, buf: cstring, size: cint): cint
  {.cdecl, dynlib: libName, importc.}

proc pcap_geterr*(pcap: ptr pcap_T): cstring
  {.cdecl, dynlib: libName, importc.}

proc pcap_datalink*(pcap: ptr pcap_T): cint
  {.cdecl, dynlib: libName, importc.}

proc pcap_set_snaplen*(pcap: ptr pcap_T, snaplen: cint): cint 
  {.cdecl, dynlib: libName, importc.}

proc pcap_snapshot*(pcap: ptr pcap_T): cint
  {.cdecl, dynlib: libName, importc.}

proc pcap_set_promisc*(pcap: ptr pcap_T, promisc: cint): cint 
  {.cdecl, dynlib: libName, importc.}

proc pcap_set_rfmon*(pcap: ptr pcap_T, rfmon: cint): cint 
  {.cdecl, dynlib: libName, importc.}

proc pcap_can_set_rfmon*(pcap: ptr pcap_T): cint
  {.cdecl, dynlib: libName, importc.}

proc pcap_set_timeout*(pcap: ptr pcap_T, to_ms: cint): cint 
  {.cdecl, dynlib: libName, importc.}

proc pcap_set_buffer_size*(pcap: ptr pcap_T, buffer_size: cint): cint
  {.cdecl, dynlib: libName, importc.}

proc pcap_create*(source: cstring, errbuf: pointer): ptr pcap_t
  {.cdecl, dynlib: libName, importc.}

proc pcap_activate*(pcap: ptr pcap_T): cint
  {.cdecl, dynlib: libName, importc.}

proc checkError*(pcap: ptr pcap_T, ret: cint) =
  if ret < 0:
    raise newException(OSError, $pcap_geterr(pcap))


when isMainModule:
  var err = newString(PCAP_ERRBUF_SIZE)
  var filter: ptr bpf_program
  var p = pcap_create(defaultIfName, err[0].addr)

  # Produces a malloc error
  # malloc: *** error for object 0x408: pointer being freed was not allocated
  p.checkError p.pcap_compile(filter, "tcp port 2050", 1, PCAP_NETMASK_UNKNOWN)