A given protocol's packet format may depend, for example, on which
lower-level protocol is transporting the protocol in question. For
example, protocols that run atop both byte-stream protocols such as TCP
and TLS, and packet-oriented protocols such as UDP or DTLS, might begin
the packet with a length when running atop a byte-stream protocol, to
indicate where this packet ends and the next packet begins in the byte
stream, but not do so when running atop a packet-oriented protocol.
Dissectors can handle this in various ways:
For example, the dissector could attempt to determine the protocol over
which the packet was transported.
Unfortunately, many of those mechanisms do so by fetching data from the
packet_info structure, and many items in that structure act as global
variables, so that, for example, if there are two two PDUs for protocol
A inside a TCP segment, and the first protocol for PDU A contains a PDU
for protocol B, and protocol B's dissector, or a dissector it calls,
modifies the information in the packet_info structure so that it no
longer indicates that the parent protocol is TCP, the second PDU for
protocol A might not be correctly dissected.
Another such mechanism is to query the previous element in the layers
structure of the packet_info structure, which is a list of protocol IDs.
Unfortunately, that is not a list of earlier protocols in the protocol
stack, it's a list of earlier protocols in the dissection, which means
that, in the above example, when the second PDU for protocol A is
dissected, the list is {...,TCP,A,B,...,A}, which means that the
previous element in the list is not TCP, so, again, the second PDU for
protocol A will not be correctly dissected.
An alternative is to have multiple dissectors for the same protocol,
with the part of the protocol that's independent of the protocol
transporting the PDU being dissected by common code. Protocol B might
have an "over a byte-stream transport" dissector and an "over a packet
transport" dissector, with the first dissector being registered for use
over TCP and TLS and the other dissector being registered for use over
packet protocols. This mechanism, unlike the other mechanisms, is not
dependent on information in the packet_info structure that might be
affected by dissectors other than the one for the protocol that
transports protocol B.
Furthermore, in a LINKTYPE_WIRESHARK_UPPER_PDU pcap or pcapng packet for
protocol B, there might not be any information to indicate the protocol
that transports protocol B, so there would have to be separate
dissectors for protocol B, with separate names, so that a tag giving the
protocol name would differ for B-over-byte-stream and B-over-packets.
So:
We rename EXP_PDU_TAG_PROTO_NAME and EXP_PDU_TAG_HEUR_PROTO_NAME to
EXP_PDU_TAG_DISSECTOR_NAME and EXP_PDU_TAG_HEUR_DISSECTOR_NAME, to
emphasize that they are *not* protocol names, they are dissector names
(which has always been the case - if there's a protocol with that name,
but no dissector with that name, Wireshark will not be able to handle
the packet, as it will try to look up a dissector given that name and
fail).
We fix that exported PDU dissector to refer to those tags as dissector
names, not protocol names.
We update documentation to refer to them as DISSECTOR_NAME tags, not
PROTO_NAME tags. (If there is any documentation for this outside the
Wireshark source, it should be updated as well.)
We add comments for calls to dissector_handle_get_dissector_name() where
the dissector name is shown to the user, to indicate that it might be
that the protocol name should be used.
We update the TLS and DTLS dissectors to show the encapsulated protocol
as the string returned by dissector_handle_get_long_name(); as the
default is "Application Data", it appeaers that a descriptive name,
rather than a short API name, should be used. (We continue to use the
dissector name in debugging messages, to indicate which dissector was
called.)
nettrace_3gpp_32_423.c:256:2: warning: Value stored to 'prev_pos' is never read [deadcode.DeadStores]
nettrace_3gpp_32_423.c:295:2: warning: Value stored to 'next_msg_pos' is never read [deadcode.DeadStores]
nettrace_3gpp_32_423.c:487:4: warning: Value stored to 'port_type_defined' is never read [deadcode.DeadStores]
Without that, you could add a comment to a record in a file format the
reading code for which doesn't allocate blocks, but the comment doesn't
get saved, as there's no block in which to save the comment option.
This simplifies some code paths, as we're either using the record's
modified block or we're using the block as read from the file, there's
no third possibility.
If we attempt to read a record, and we get an error, and a block was
allocated for the record, unreference it, so the individual file readers
don't have to worry about it.
Have wsutil/exported_pdu_tlvs.h define the LINKTYPE_WIRESHARK_UPPER_PDU
TLV type and length values, as well as the port type values written to
files in EXP_PDU_TAG_PORT_TYPE TLVs.
Update the comment that describes the LINKTYPE_WIRESHARK_UPPER_PDU TLVs
to more completely and correctly reflect reality (it was moved from
epan/exported_pdu.h to wsutil/exported_pdu_tlvs.h).
Rename those port type values from OLD_PT_ to EXP_PDU_PT_; there is
nothing "old" about them - yes, they originally had the same numerical
values as the PT_ enum values in libwireshark, but that's no longer the
case, and the two are now defined independently. Rename routines that
map between libwireshark PT_ values and EXP_PDU_PT_ values to remove
"old" from the name while we're at it.
Don't include epan/exported_pdu.h if we only need the
LINKTYPE_WIRESHARK_UPPER_PDU definitions - just include
wsutil/exported_pdu_tlvs.h.
In extcap/udpdump.c, include wsutil/exported_pdu_tlvs.h rather than
defining the TLV types ourselves.
Initialize name_str right before we fill it in if the name is present,
and note what we're doing, to make it a bit clearer what the
initializing code is doing.
Within wiretap/nettrace_3gpp_32_423.c,
set the first byte of the buffer
to a null byte to avoid potentially
accessing uninitiliazed memory.
Fixes Coverity 1471685.
Most of the time, the return value tells us nothing useful, as we've
already decided that we're perfectly willing to live with string
truncation. Hopefully this keeps Coverity from whining that those
routines could return an error code (NARRATOR: They don't) and thus that
we're ignoring the possibility of failure (as indicated, we've already
decided that we can live with string truncation, so truncation is *NOT*
a failure).
It only registers one file type/subtype, so rename it to
wtap_register_file_type_subtype().
That will also force plugins to be recompiled; that will produce compile
errors for some plugins that didn't change to match the new contents of
the file_type_subtype_info structure.
Also check to make sure that the registered file type/subtype supports
at least one type of block; a file type/subtype that doesn't return
*any* blocks and doesn't permit *any* block types to be written is not
very useful. That should also catch most if not all other plugins that
didn't change to match the new contents of the file_type_subtype_info
structure.
Don't make errors registering a file type/subtype fatal; just complain,
don't register the bogus file type/subtype, and drive on.
Instead of a "supports name resolution" Boolean and bitflags for types of
comments supported, provide a list of block types that the file
type/subtype supports, with each block type having a list of options
supported. Indicate whether "supported" means "one instance" or
"multiple instances".
"Supports" doesn't just mean "can be written", it also means "could be
read".
Rename WTAP_BLOCK_IF_DESCRIPTION to WTAP_BLOCK_IF_ID_AND_INFO, to
indicate that it provides, in addition to information about the
interface, an ID (implicitly, in pcapng files, by its ordinal number)
that is associated with every packet in the file. Emphasize that in
comments - just because your capture file format can list the interfaces
on which a capture was done, that doesn't mean it supports this; it
doesn't do so if the file doesn't indicate, for every packet, on which
of those interfaces it was captured (I'm looking at *you*, Microsoft
Network Monitor...).
Use APIs to query that information to do what the "does this file
type/subtype support name resolution information", "does this file
type/subtype support all of these comment types", and "does this file
type/subtype support - and require - interface IDs" APIs did.
Provide backwards compatibility for Lua.
This allows us to eliminate the WTAP_FILE_TYPE_SUBTYPE_ values for IBM's
iptrace; do so.
Provide a wiretap routine to get an array of all savable file
type/subtypes, sorted with pcap and pcapng at the top, followed by the
other types, sorted either by the name or the description.
Use that routine to list options for the -F flag for various commands
Rename wtap_get_savable_file_types_subtypes() to
wtap_get_savable_file_types_subtypes_for_file(), to indicate that it
provides an array of all file type/subtypes in which a given file can be
saved. Have it sort all types, other than the default type/subtype and,
if there is one, the "other" type (both of which are put at the top), by
the name or the description.
Don't allow wtap_register_file_type_subtypes() to override any existing
registrations; have them always register a new type. In that routine,
if there are any emply slots in the table, due to an entry being
unregistered, use it rather than allocating a new slot.
Don't allow unregistration of built-in types.
Rename the "dump open table" to the "file type/subtype table", as it has
entries for all types/subtypes, even if we can't write them.
Initialize that table in a routine that pre-allocates the GArray before
filling it with built-in types/subtypes, so it doesn't keep getting
reallocated.
Get rid of wtap_num_file_types_subtypes - it's just a copy of the size
of the GArray.
Don't have wtap_file_type_subtype_description() crash if handed an
file type/subtype that isn't a valid array index - just return NULL, as
we do with wtap_file_type_subtype_name().
In wtap_name_to_file_type_subtype(), don't use WTAP_FILE_TYPE_SUBTYPE_
names for the backwards-compatibility names - map those names to the
current names, and then look them up. This reduces the number of
uses of hardwired WTAP_FILE_TYPE_SUBTYPE_ values.
Clean up the type of wtap_module_count - it has no need to be a gulong.
Have built-in wiretap file handlers register names to be used for their
file type/subtypes, rather than building the table in init.lua.
Add a new Lua C function get_wtap_filetypes() to construct the
wtap_filetypes table, based on the registered names, and use it in
init.lua.
Add a #define WSLUA_INTERNAL_FUNCTION to register functions intended
only for internal use in init.lua, so they can be made available from
Lua without being documented.
Get rid of WTAP_NUM_FILE_TYPES_SUBTYPES - most code has no need to use
it, as it can just request arrays of types, and the space of
type/subtype codes can be sparse due to registration in any case, so
code has to be careful using it.
wtap_get_num_file_types_subtypes() is no longer used, so remove it. It
returns the number of elements in the file type/subtype array, which is
not necessarily the name of known file type/subtypes, as there may have
been some deregistered types, and those types do *not* get removed from
the array, they just get cleared so that they're available for future
allocation (we don't want the indices of any registered types to changes
if another type is deregistered, as those indicates are the type/subtype
values, so we can't shrink the array).
Clean up white space and remove some comments that shouldn't have been
added.
Remove most of the built-in file types from the table in
wiretap/file_access.c and, instead, have the file types register
themselves, using wtap_register_file_type_subtypes().
This reduces the source code changes needed to add a new file type from
three (add the handler, add the file type to the table in file_access.c,
add a #define for the file type in wiretap/wtap.h) to one (add the
handler). (It also requires adding the handler's source file to
wiretap/CMakeLists.txt, but that's required in both cases.)
A few remain because the WTAP_FILE_TYPE_SUBTYPE_ #define is used
elsewhere; that needs to be fixed.
Fix the wiretap/CMakefile.txt file to scan k12text.l, as that now
contains a registration routine. In the process, avoid scanning files
that don't implement a file type and won't ever have a registration
routine.
Add a Lua routine to fetch the total number of file types; we use that
in some code to construct the wtap_filetypes table, which we need to do
in order to continue to have all the values that used to come from the
WTAP_FILE_TYPE_SUBTYPE_ types.
While we're at it, add modelines to a file that lacked them.
This adds a function to parse a string date-time in ISO 8601 format into
a `nstime_t` structure. It's based on code from epan/tvbuff.c and
wiretap/nettrace_3gpp_32_423.c and meant to eventually replace both.
(Currently only replaces the latter.)
Since most of Wireshark expects ISO 8601 date-times to fit a fairly
strict pattern, iso8601_to_nstime() currently rejects date-times without
separators between the components, even though ISO 8601 actually permits
this. This could be revisited later.
Also uses iso8601_to_nstime in editcap to parse the -A/-B options,
thus allowing the user to specify a time zone if desired. (See #17110)
Old behaviour is to read the entire file into memory at once; provide
the XML tree as the first packet; and then individual `<msg>` elements
as subsequent packets. It did this by writing to a temporary pcapng
file.
This change causes the XML file to only be read a chunk at a time (and
be read directly, not through an intermediate pcapng). This means much
larger files can be loaded, at the cost of no longer showing the raw XML
as the first packet. This is not a loss because the file can be loaded
in MIME Files Format (or a text editor) to see the XML.
Much of the logic from the old functions `create_temp_pcapng_file()` and
`write_packet_data()` has been relocated into the new function
`nettrace_msg_to_packet()`, and is used to directly generate packet data
for wiretap instead of writing it to a temporary file.
Also includes some initial "code smell" fixes:
- Removed some duplicate `#define`s from epan/exported_pdu.h
- Replaces some magic numbers with macros from epan/exported_pdu.h
- Replaces other magic numbers with the CLEN() macro to make it easier
to see (and debug) where sizes/offsets come from
- Use `g_strstr_len()` instead of `strstr()` to remove the need to
insert string terminators
- Uses direct pointer math instead of indexing into a byte array
This compiles and runs, and seems to produce the same results as the old
reader (except for the XML packet). Consider it a proof of concept; it
needs further revision before being review-ready.
A nettrace 3gpp capture contains the 'beginTime' in ISO 8601 format.
This patch corrects the conversion for the following steps:
- the UTC offset must be subtracted from the given time,
- given time must be converted to UTC time when an offset is provided (localtime otherwise)
- sub-seconds conversion fixed (i.e. .0012 was converted to .12).
Closes#16888
A long time ago, in a galaxy far far away, C had arithmetic/logical-
plus-assignment operators, so that
a = a {op} x;
could be written as
a ={op} x;
Unfortunately, if {op} is -, that meant that you could have, for
example:
a =- 17;
which could be interpreted as
a = -17;
so they changed the operators to be
a {op}= x;
I.e., if you want to subtract 1000 from a variable, do
elapsed_ms -= 1000;
not
elapsed_ms =- 1000;
Fix dead store (Dead assignement/Dead increment) Warning found by Clang
Change-Id: I6316d82fec8ee87f56cabe27e269cc7ef98cedc8
Reviewed-on: https://code.wireshark.org/review/36842
Petri-Dish: Alexis La Goutte <alexis.lagoutte@gmail.com>
Tested-by: Petri Dish Buildbot
Reviewed-by: Anders Broman <a.broman58@gmail.com>
Much better to use a known library than create it ourselves.
Also remove get_tempfile_path as it's not used.
Bug: 15992
Change-Id: I17b9bd879e8bdb540f79db83c6c138f8ee724764
Reviewed-on: https://code.wireshark.org/review/34420
Reviewed-by: Tomasz Moń <desowin@gmail.com>
Petri-Dish: Tomasz Moń <desowin@gmail.com>
Tested-by: Petri Dish Buildbot
Reviewed-by: Roland Knall <rknall@gmail.com>
Fall back on the Wayback Machine for some links.
Change-Id: I6a44a2caaeb4fa521c2f08196e7c36069e3bb842
Reviewed-on: https://code.wireshark.org/review/34103
Reviewed-by: Guy Harris <guy@alum.mit.edu>
Change all wireshark.org URLs to use https.
Fix some broken links while we're at it.
Change-Id: I161bf8eeca43b8027605acea666032da86f5ea1c
Reviewed-on: https://code.wireshark.org/review/34089
Reviewed-by: Guy Harris <guy@alum.mit.edu>
That makes it - and the routines that implement it - work more like the
seek-read routine.
Change-Id: I0cace2d0e4c9ebfc21ac98fd1af1ec70f60a240d
Reviewed-on: https://code.wireshark.org/review/32727
Petri-Dish: Guy Harris <guy@alum.mit.edu>
Tested-by: Petri Dish Buildbot
Reviewed-by: Guy Harris <guy@alum.mit.edu>
The memory ownership of wtap_rec::opt_comment was not clear. Users of
wtap were leaking memory (editcap.c). wtap readers were not sure about
freeing old comments (erf) or simply ignored memleaks (pcapng).
To fix this, ensure opt_comment is owned by wtap_rec and free it with
wtap_rec_cleanup. The erf issue was already addressed since
cf_get_packet_comment properly duplicates wth.opt_comment memory.
- wtap file formats (readers):
- Should allocate memory for new comments.
- Should free a comment from an earlier read before writing a new one.
- Users of wth:
- Can only assume that opt_comment remains valid until the next read.
- Can assume that wtap_dump does not modify the comment.
- For random access (wtap_seek_read): should call wtap_rec_cleanup
to free the comment.
The test_tshark_z_expert_comment and test_text2pcap_sip_pcapng tests now
pass when built with ASAN.
This change was created by carefully looking at all users opt
"opt_comment" and cf_get_packet_comment. Thanks to Vasil Velichkov for
an initial patch which helped validating this version.
Bug: 7515
Change-Id: If3152d1391e7e0d9860f04f3bc2ec41a1f6cc54b
Reviewed-on: https://code.wireshark.org/review/31713
Petri-Dish: Peter Wu <peter@lekensteyn.nl>
Tested-by: Petri Dish Buildbot
Reviewed-by: Vasil Velichkov <vvvelichkov@gmail.com>
Reviewed-by: Anders Broman <a.broman58@gmail.com>
sscanf can consume less than 19 characters (e.g. given time format
1-1-1T1:1:1), be sure to reject such input. Fix some dead store warning
while at it.
Change-Id: I6148599048f1e89ea7aafdbdd6450574a97b22fd
Fixes: v2.9.1rc0-372-gd38f6025b0 ("nettrace: Handle beginTime with fractions of seconds.")
Reviewed-on: https://code.wireshark.org/review/31699
Petri-Dish: Peter Wu <peter@lekensteyn.nl>
Tested-by: Petri Dish Buildbot
Reviewed-by: Anders Broman <a.broman58@gmail.com>
Avoid including the precise version string in the pcapng file that is
created for 3GPP TS 32.423 formats. This avoids unnecessarily relinking
of applications depending on wiretap.
Change-Id: Ida1f3c0c998d811cbf85734bd83438bcbfc39cf4
Reviewed-on: https://code.wireshark.org/review/31513
Petri-Dish: Peter Wu <peter@lekensteyn.nl>
Reviewed-by: João Valverde <j@v6e.pt>
Petri-Dish: João Valverde <j@v6e.pt>
Tested-by: Petri Dish Buildbot
Reviewed-by: Anders Broman <a.broman58@gmail.com>
Have a ws_init_version_info() routine that, given an application name
string:
constructs the app-name-and-version-information string, and
saves it;
adds the initial crash information on platforms that support it,
and saves it.
Have show_version() use the saved information and take no arguments.
Add a show_help_header() routine to print the header for --help
command-line options, given a description of the application; it prints
the application name and version information, the description, and the
"See {wireshark.org URL}" line.
Use those routines in various places, including providing the
"application name" string in pcapng SHBs.
Change-Id: I0042a8fcc91aa919ad5c381a8b8674a007ce66df
Reviewed-on: https://code.wireshark.org/review/31029
Petri-Dish: Guy Harris <guy@alum.mit.edu>
Tested-by: Petri Dish Buildbot
Reviewed-by: Guy Harris <guy@alum.mit.edu>
This:
1) means that we don't have to flag the compression argument with a
comment to indicate what it means (FALSE doesn't obviously say "not
compressed", WTAP_UNCOMPRESSED does);
2) leaves space in the interfaces in question for additional compression
types.
(No, this is not part 1 of an implementation of additional compression
types, it's just an API cleanup. Implementing additional compression
types involves significant work in libwiretap, as well as UI changes to
replace "compress the file" checkboxes with something to indicate *how*
to compress the file, or to always use some other form of compression).
Change-Id: I1d23dc720be10158e6b34f97baa247ba8a537abf
Reviewed-on: https://code.wireshark.org/review/30660
Petri-Dish: Guy Harris <guy@alum.mit.edu>
Tested-by: Petri Dish Buildbot
Reviewed-by: Guy Harris <guy@alum.mit.edu>
Use it for all the per-file information, including the per-file
link-layer type and the per-file snapshot length.
Change-Id: Id75687c7faa6418a2bfcf7f8198206a9f95db629
Reviewed-on: https://code.wireshark.org/review/30616
Petri-Dish: Guy Harris <guy@alum.mit.edu>
Tested-by: Petri Dish Buildbot
Reviewed-by: Peter Wu <peter@lekensteyn.nl>
Have the routines always take a parameters pointer; pass either null or
a pointer to an initialized-to-nothing structure in cases where we were
calling the non-_ng versions.
Change-Id: I23b779d87f3fbd29306ebe1df568852be113d3b2
Reviewed-on: https://code.wireshark.org/review/30590
Petri-Dish: Guy Harris <guy@alum.mit.edu>
Tested-by: Petri Dish Buildbot
Reviewed-by: Guy Harris <guy@alum.mit.edu>
Guy Harris