search

msantos / pkt

Erlang network protocol library
http://blog.listincomprehension.com/search/label/epcap
BSD 3-Clause "New" or "Revised" License
150 stars 44 forks source link

handle chunks that are too short #51

Closed massemanet closed 5 years ago

massemanet commented 5 years ago

when decode_chunks is called with a binary that's longer than 4 bytes, but shorter than Length, the match on line 58 will fail.

can happen e.g. in truncated files.

msantos commented 5 years ago

Thanks!

Seeing 4 test failures:

$ rebar3 eunit

Failures:

  1) pkt_sctp_tests:cookie_echo_chunk/0:100
     Failure/Error: {error,
                        {badmatch,<<21,235,131,195,114,0,0,0>>},
                        [{pkt_sctp,decode_chunks,2,
                             [{file,
                                  "/home/msantos/src/erlang/pkt/_build/test/lib/pkt/src/pkt_sctp.erl"},
                              {line,57}]},
                         {pkt_sctp,codec,1,
                             [{file,
                                  "/home/msantos/src/erlang/pkt/_build/test/lib/pkt/src/pkt_sctp.erl"},
                              {line,39}]},
                         {pkt_sctp_tests,'-cookie_echo_chunk/0-fun-0-',1,
                             [{file,
                                  "/home/msantos/src/erlang/pkt/_build/test/lib/pkt/test/pkt_sctp_tests.erl"},
                              {line,100}]},
                         {eunit_test,run_testfun,1,
                             [{file,"eunit_test.erl"},{line,71}]},
                         {eunit_proc,run_test,1,
                             [{file,"eunit_proc.erl"},{line,510}]},
                         {eunit_proc,with_timeout,3,
                             [{file,"eunit_proc.erl"},{line,335}]},
                         {eunit_proc,handle_test,2,
                             [{file,"eunit_proc.erl"},{line,493}]},
                         {eunit_proc,tests_inorder,3,
                             [{file,"eunit_proc.erl"},{line,435}]}]}
     Output:
  2) pkt_sctp_tests:data_chunk/0:139
     Failure/Error: {error,
                        {badmatch,
                            <<1,34,28,185,0,0,0,0,0,0,0,0,84,101,115,116,32,
                              48,0,0>>},
                        [{pkt_sctp,decode_chunks,2,
                             [{file,
                                  "/home/msantos/src/erlang/pkt/_build/test/lib/pkt/src/pkt_sctp.erl"},
                              {line,57}]},
                         {pkt_sctp,codec,1,
                             [{file,
                                  "/home/msantos/src/erlang/pkt/_build/test/lib/pkt/src/pkt_sctp.erl"},
                              {line,39}]},
                         {pkt_sctp_tests,'-data_chunk/0-fun-0-',1,
                             [{file,
                                  "/home/msantos/src/erlang/pkt/_build/test/lib/pkt/test/pkt_sctp_tests.erl"},
                              {line,139}]},
                         {eunit_test,run_testfun,1,
                             [{file,"eunit_test.erl"},{line,71}]},
                         {eunit_proc,run_test,1,
                             [{file,"eunit_proc.erl"},{line,510}]},
                         {eunit_proc,with_timeout,3,
                             [{file,"eunit_proc.erl"},{line,335}]},
                         {eunit_proc,handle_test,2,
                             [{file,"eunit_proc.erl"},{line,493}]},
                         {eunit_proc,tests_inorder,3,
                             [{file,"eunit_proc.erl"},{line,435}]}]}
     Output:
  3) pkt_sctp_tests:heartbeat_chunk/0:180
     Failure/Error: {error,
                        {badmatch,<<0,1,0,9,2,0,7,214,192,0,0,0>>},
                        [{pkt_sctp,decode_chunks,2,
                             [{file,
                                  "/home/msantos/src/erlang/pkt/_build/test/lib/pkt/src/pkt_sctp.erl"},
                              {line,57}]},
                         {pkt_sctp,codec,1,
                             [{file,
                                  "/home/msantos/src/erlang/pkt/_build/test/lib/pkt/src/pkt_sctp.erl"},
                              {line,39}]},
                         {pkt_sctp_tests,'-heartbeat_chunk/0-fun-0-',1,
                             [{file,
                                  "/home/msantos/src/erlang/pkt/_build/test/lib/pkt/test/pkt_sctp_tests.erl"},
                              {line,180}]},
                         {eunit_test,run_testfun,1,
                             [{file,"eunit_test.erl"},{line,71}]},
                         {eunit_proc,run_test,1,
                             [{file,"eunit_proc.erl"},{line,510}]},
                         {eunit_proc,with_timeout,3,
                             [{file,"eunit_proc.erl"},{line,335}]},
                         {eunit_proc,handle_test,2,
                             [{file,"eunit_proc.erl"},{line,493}]},
                         {eunit_proc,tests_inorder,3,
                             [{file,"eunit_proc.erl"},{line,435}]}]}
     Output:
  4) pkt_sctp_tests:heartbeat_ack_chunk/0:198
     Failure/Error: {error,
                        {badmatch,<<0,1,0,9,2,0,7,214,192,0,0,0>>},
                        [{pkt_sctp,decode_chunks,2,
                             [{file,
                                  "/home/msantos/src/erlang/pkt/_build/test/lib/pkt/src/pkt_sctp.erl"},
                              {line,57}]},
                         {pkt_sctp,codec,1,
                             [{file,
                                  "/home/msantos/src/erlang/pkt/_build/test/lib/pkt/src/pkt_sctp.erl"},
                              {line,39}]},
                         {pkt_sctp_tests,'-heartbeat_ack_chunk/0-fun-0-',1,
                             [{file,
                                  "/home/msantos/src/erlang/pkt/_build/test/lib/pkt/test/pkt_sctp_tests.erl"},
                              {line,198}]},
                         {eunit_test,run_testfun,1,
                             [{file,"eunit_test.erl"},{line,71}]},
                         {eunit_proc,run_test,1,
                             [{file,"eunit_proc.erl"},{line,510}]},
                         {eunit_proc,with_timeout,3,
                             [{file,"eunit_proc.erl"},{line,335}]},
                         {eunit_proc,handle_test,2,
                             [{file,"eunit_proc.erl"},{line,493}]},
                         {eunit_proc,tests_inorder,3,
                             [{file,"eunit_proc.erl"},{line,435}]}]}
     Output:
massemanet commented 5 years ago

ouch. didn't realize there was a test suite... I'll fix and push

massemanet commented 5 years ago

I changed the pad length to be in bytes (because chunk length is in bytes), but forgot to change the match. D'oh

msantos commented 5 years ago

Thank you!