Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.8/site-packages/nfstream/engine/engine.py: 15%

1""" 

2------------------------------------------------------------------------------------------------------------------------ 

3engine.py 

4Copyright (C) 2019-22 - NFStream Developers 

5This file is part of NFStream, a Flexible Network Data Analysis Framework (https://www.nfstream.org/). 

6NFStream is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public 

7License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later 

8version. 

9NFStream is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty 

10of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. 

11You should have received a copy of the GNU Lesser General Public License along with NFStream. 

12If not, see <http://www.gnu.org/licenses/>. 

13------------------------------------------------------------------------------------------------------------------------ 

14""" 

15 

16from _lib_engine import ffi, lib 

17 

18 

19def setup_capture( 

20 ffi, lib, source, snaplen, promisc, mode, error_child, group_id, socket_buffer_size 

21): 

22 capture = lib.capture_open( 

23 bytes(source, "utf-8"), int(mode), error_child, socket_buffer_size 

24 ) 

25 if capture == ffi.NULL: 

26 return 

27 fanout_set_failed = lib.capture_set_fanout( 

28 capture, int(mode), error_child, group_id 

29 ) 

30 if fanout_set_failed: 

31 return 

32 timeout_set_failed = lib.capture_set_timeout(capture, int(mode), error_child) 

33 if timeout_set_failed: 

34 return 

35 promisc_set_failed = lib.capture_set_promisc( 

36 capture, int(mode), error_child, int(promisc) 

37 ) 

38 if promisc_set_failed: 

39 return 

40 snaplen_set_failed = lib.capture_set_snaplen( 

41 capture, int(mode), error_child, snaplen 

42 ) 

43 if snaplen_set_failed: 

44 return 

45 return capture 

46 

47 

48def setup_filter(capture, lib, error_child, bpf_filter): 

49 """Compile and setup BPF filter""" 

50 if bpf_filter is not None: 

51 filter_set_failed = lib.capture_set_filter( 

52 capture, bytes(bpf_filter, "utf-8"), error_child 

53 ) 

54 if filter_set_failed: 

55 return False 

56 return True 

57 

58 

59def activate_capture(capture, lib, error_child, bpf_filter, mode): 

60 """Capture activation function""" 

61 activation_failed = lib.capture_activate(capture, int(mode), error_child) 

62 if activation_failed: 

63 return False 

64 return setup_filter(capture, lib, error_child, bpf_filter) 

65 

66 

67def setup_dissector(ffi, lib, n_dissections): 

68 """Setup dissector according to n_dissections value""" 

69 if n_dissections: # Dissection activated 

70 # Check that headers and loaded library match and initiate dissector. 

71 checker = ffi.new("struct dissector_checker *") 

72 checker.flow_size = ffi.sizeof("struct ndpi_flow_struct") 

73 checker.flow_tcp_size = ffi.sizeof("struct ndpi_flow_tcp_struct") 

74 checker.flow_udp_size = ffi.sizeof("struct ndpi_flow_udp_struct") 

75 dissector = lib.dissector_init(checker) 

76 if dissector == ffi.NULL: 

77 return ffi.NULL 

78 # Configure it (activate bitmask to all protocols) 

79 lib.dissector_configure(dissector) 

80 return dissector 

81 return ffi.NULL 

82 

83 

84def is_interface(val): 

85 """Check if val is a valid interface name and return it if true else None""" 

86 intf = lib.capture_get_interface(val.encode("ascii")) 

87 if intf == ffi.NULL: 

88 return None 

89 return ffi.string(intf).decode("ascii", "ignore") 

90 

91 

92def create_engine(): 

93 """engine creation function, return the loaded native nfstream engine and it's ffi interface""" 

94 return ffi, lib