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2003-12-20Do the special "if the first fragment we see is also the final fragment,Guy Harris1-14/+26
treat it as a reassembled frame" hack *only* for 802.11, as that's the only protocol we know of that requires it. svn path=/trunk/; revision=9367
2003-08-28Make "process_reassembled_data()" do the check for fragmentation notGuy Harris1-3/+3
being complete and for fragmentation being trivial (i.e., the packet in question is both the first and last fragment). Have its callers *not* do that check - this lets "process_reassembled_data()" put in the "Reassembled in" item for fragments other than the last fragment. Add a "Reassembled in" field to TDS. svn path=/trunk/; revision=8295
2003-06-04There can be more than one DCE RPC call per frame, e.g. there can beGuy Harris1-11/+1
multiple NetBIOS-over-TCP session service messages in a TCP segment, and they can contain the final portions of different DCERPC calls. Don't assume a frame number is sufficient to identify DCE RPC calls. svn path=/trunk/; revision=7777
2003-04-20Add a pointer to an hf_ value for a "reassembled_in" field (which can beGuy Harris1-6/+9
null) to the "fragment_items" structure, and don't pass that value into "process_reassembled_data()", just have it use the value in the "fragment_items" structure passed to it. Make "process_reassembled_data()" capable of handling reassembly done by "fragment_add_seq_check()", and use it in the ATP and 802.11 dissectors; give them "reassembled_in" fields. Make "process_reassembled_data()" handle only the case of a completed reassembly (fd_head != NULL) so that we can use it in those dissectors without gunking the code up too much. svn path=/trunk/; revision=7513
2003-04-20Pull much of the processing done after a call to "fragment_add_check()"Guy Harris1-1/+6
into a subroutine, for use in other dissectors. Use it in the IPv6 and CLNP dissectors. svn path=/trunk/; revision=7510
2003-04-20Add a "fragment_add_multiple_ok()" routine that skips the check for aGuy Harris1-1/+4
fragment having been added already. In protocols using the ONC RPC-over-TCP record-marking mechanism (RPC-over-TCP and NDMP), there can be more than one record-marking-layer fragment in a single TCP segment, and thus can be more than one fragment in a frame being added to a given higher-level packet. svn path=/trunk/; revision=7508
2003-04-20We can't use the frame_data structure as a key structure when lookingGuy Harris1-1/+13
for reassembled frames - in Tethereal, there's only one frame_data structure used for all frames. Instead, use the frame number itself as the key. Add a "fragment_add_check()" routine, for fragments where there's a fragment offset rather than a fragment sequence number, which does the same sort of thing as "fragment_add_seq_check()" - i.e., once reassembly is done, it puts the reassembled fragment into a separate hash table, so that there're only incomplete reassemblies in the fragment hash table. That's necessary in order to handle cases where the packet ID field can be reused. Use that routine for IPv4 fragment reassembly - IP IDs can be reused (in fact, RFC 791 suggests that doing so might be a feature: It is appropriate for some higher level protocols to choose the identifier. For example, TCP protocol modules may retransmit an identical TCP segment, and the probability for correct reception would be enhanced if the retransmission carried the same identifier as the original transmission since fragments of either datagram could be used to construct a correct TCP segment. and RFC 1122 says that it's permitted to do so, although it also says "we believe that retransmitting the same Identification field is not useful": 3.2.1.5 Identification: RFC-791 Section 3.2 When sending an identical copy of an earlier datagram, a host MAY optionally retain the same Identification field in the copy. DISCUSSION: Some Internet protocol experts have maintained that when a host sends an identical copy of an earlier datagram, the new copy should contain the same Identification value as the original. There are two suggested advantages: (1) if the datagrams are fragmented and some of the fragments are lost, the receiver may be able to reconstruct a complete datagram from fragments of the original and the copies; (2) a congested gateway might use the IP Identification field (and Fragment Offset) to discard duplicate datagrams from the queue. However, the observed patterns of datagram loss in the Internet do not favor the probability of retransmitted fragments filling reassembly gaps, while other mechanisms (e.g., TCP repacketizing upon retransmission) tend to prevent retransmission of an identical datagram [IP:9]. Therefore, we believe that retransmitting the same Identification field is not useful. Also, a connectionless transport protocol like UDP would require the cooperation of the application programs to retain the same Identification value in identical datagrams. and, in any case, I've seen that in at least one capture, and it confuses the current reassembly code). Unfortunately, that means that fragments other than the last fragment can't be tagged with the frame number in which the reassembly was done; see the comment in packet-ip.c for a discussion of that problem. svn path=/trunk/; revision=7506
2003-04-09Added new field reassembled_in to the fragment data structure.Ronnie Sahlberg1-1/+4
This field gets set to the frame number when this pdu was first completely reassembled. This is useful since it will allow us to do reassembly properly in say packet-ip.c instead of printing the full pdu for every fragment and thus making NFSoverUDP rpc-rtt statistics less than useful. A dissector using fragment_add() can tehn choose to only dissect the reassembled PDU only for the frame where it was first reassembled. svn path=/trunk/; revision=7427
2002-12-19Update reassemble.c/show_item and all callers to use FT_FRAMENUM for the ↵Ronnie Sahlberg1-1/+4
list of packets corresponding to a reassembled pdu svn path=/trunk/; revision=6807
2002-11-14From Tomas Kukosa: export more routines to plugins.Guy Harris1-12/+12
svn path=/trunk/; revision=6630
2002-10-24Add a "fragment_add_seq_next()" to reassemble fragments that don't haveGuy Harris1-6/+15
sequence numbers or offsets and are thus assumed to be received in order with no duplicates or dropped fragments (e.g., for NetBIOS Frame, where 802.2 LLC guarantees in-order delivery to NetBIOS with no duplicates or dropped fragments). "show_fragment_tree()' and "show_fragment_seq_tree()" don't modify the "fragment_items" to which the "fit" argument points, so make that argument a "const fragment_items *". Make all the "fragment_items" tables "static" (as they're not used outside the modules defining them) and "const" (as they're not modified). Add support for reassembly of NetBIOS fragmented requests and responses. Get rid of an unnecessary include of "packet-tr.c" in the NetBIOS dissector, and make its table of dissection function pointers static. Fix some typos in the AppleTalk and NetBIOS dissectors. svn path=/trunk/; revision=6491
2002-08-28Removed trailing whitespaces from .h and .c files using theJörg Mayer1-13/+13
winapi_cleanup tool written by Patrik Stridvall for the wine project. svn path=/trunk/; revision=6117
2002-06-07Add "show_fragment_seq_tree()", which is like "show_fragment_tree()",Guy Harris1-3/+11
but for stuff reassembled with "fragment_add_seq()" or "fragment_add_seq_check()". Add a "fragment tag" string to the "fragment_items", so that packets with fragmentation errors can be properly flagged as having "Illegal fragments" or "Illegal segments" depending on the term used with the protocol in question. Make all the dissectors that can use "show_fragment_tree()" or "show_fragment_seq_tree()", and don't already use them, do so. svn path=/trunk/; revision=5644
2002-06-05Added show_fragment_tree() to reassemble. This function will do the commonRonnie Sahlberg1-1/+17
task of creating a fregment tree for the fragmented packets. Having this identical code to create this tree in every dissector that does PDU reassembly is a huge waste and duplication of code. Updated IP, SMB and DCERPC to use the new function. svn path=/trunk/; revision=5626
2002-05-24Reassembly of fragmented DCE/RPC (only for connection oriented DCE/RPC).Ronnie Sahlberg1-1/+6
svn path=/trunk/; revision=5548
2002-04-17Add a separate hash table to the reassembly code for reassembledGuy Harris1-3/+38
packets, using the reassembly ID and the frame number of the final frame as the key. There is no guarantee that reassembly IDs won't be reused, even when talking between the same source and destination address; if, once reassembly is complete, the "fragment_data" structure is moved to the latter hash table, this will keep reused reassembly IDs from causing mis-reassembly. Add a routine "fragment_add_seq_check()", which if a fragment has the "more fragments" flag not set but is the first fragment of a reassembly, treats that as a non-fragmented frame, allocating a "fragment_data" structure for the reassembly but not attaching any fragment to it, and adding it to a reassembled packet list; if a packet has been reassembled, removes it from the table of reassemblies and moves it to the table of reassembled packets; if the frame's been seen already, looks it up in the table of reassembled packets rather than the table of reassemblies. Add reassembly support for fragmented 802.11 frames. Use "fragment_add_seq_check()" to cope with the fact that some hardware+drivers apparently hands us reassembled frames with a non-zero fragment number and the "more fragments" bit clear (as if it puts the 802.11 header of the *last* fragment onto the reassembled data). svn path=/trunk/; revision=5177
2002-04-17Rename the "frag_offset" argument of "fragment_add_seq()" toGuy Harris1-4/+4
"frag_number", to make it clearer that it's not a byte offset but a sequence number. svn path=/trunk/; revision=5175
2002-02-03From Ricardo Barroetave�a: support dissectors that are handedGuy Harris1-1/+17
reassembled TCP data being able to indicate that they need still more reassembly, so that, for example, a dissector can indicate that it needs reassembly in order to dissect a header that says how long the PDU is and, when that reassembly is done and it dissects the header, it can then indicate that it needs more reassembly to get the entire PDU. svn path=/trunk/; revision=4694
2001-12-15From Ronnie Sahlberg: new infrastructure to reassemble packets whereGuy Harris1-1/+15
fragments are identified by block sequence numbers and not byte offsets. svn path=/trunk/; revision=4398
2001-11-24Assorted changes from Ronnie Sahlberg:Guy Harris1-1/+27
Add a few small functions to reassemble.c to cope with protocols where the total length of defragmented PDUs are specified in the first fragment (all previous uses of reassembly has been for PDUs where the last fragment is signalled by a flag in the header for the last fragment). Add a few small functions to reassemble.c to abort-and-delete defragmentation of PDUs and also detect IF a PDU is currently being defragmented. (Useful for PDUs where the "unique" identifier is rather ununique, or may be reused often enough so it can be a problem for Ethereal.) Change where NT Cancel presents its Cancelation-to output, and makes the three trans secondary requests also output similar information. svn path=/trunk/; revision=4255
2001-06-08Move the fragment reassembly code into "reassemble.c" andGuy Harris1-0/+77
"reassemble.h", and remove IPv4 dependencies from it. Use it for OSI CLNP segment reassembly as well. svn path=/trunk/; revision=3525