[Bug 51818] New: Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

Bug ID: 51818
           Summary: Reporting packet length is always 0
           Product: Wine
           Version: 6.18
          Hardware: x86-64
                OS: Linux
            Status: UNCONFIRMED
          Severity: major
          Priority: P2
         Component: wpcap
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

Created attachment 70703
  --> https://bugs.winehq.org/attachment.cgi?id=70703
same source for linux/mac/win

Source code for an example program is attached.

I compiled it on linux, mac and windows and it is always working as expected
meaning it produces a terminal output like:

listening on Pseudo-device that captures on all interfaces...
14:47:05,000000 len:62
Destiny MAC:
00:00:00:00:00:00:
Source MAC:
00: 00: 00: 00: 00: 00:

etc (blanked out the mac addresses)

Wheres running the windows .exe in wine always reports a packet length of 0 (I
tested on wine 6.18(linux)/6.16(linux)/6.0(linux/mac)). Modifying the program
to show the packet content leads to a segfault in wine but works just fine
again on win/linux/mac (which is kinda expected I guess since it thinks the
packets are empty).

Running native/wine versions side by side you can see that it is capturing the
same packets, which are clearly not empty.

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

--- Comment #1 from Hans Leidekker  ---
Could you provide build instructions too?

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

--- Comment #2 from [e-mail] ---
Created attachment 70725
  --> https://bugs.winehq.org/attachment.cgi?id=70725
Visual Studio solution

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

--- Comment #3 from [e-mail] ---
On *nix it is just

gcc wpcap_test.cpp -lpcap

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

--- Comment #4 from [e-mail] ---
binaries should also be included in the archive above

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

--- Comment #5 from Hans Leidekker  ---
(In reply to marc_aurel from comment #4)
> binaries should also be included in the archive above

Thanks. The problem is that the structure layout of pcap_pkthdr is different
between 64-bit Linux and 64-bit Windows. It's defined like this:

struct pcap_pkthdr {
    struct timeval ts;  /* time stamp */
    bpf_u_int32 caplen; /* length of portion present */
    bpf_u_int32 len;    /* length of this packet (off wire) */
};

The size of struct timeval is 8 bytes on 32-bit and 64-bit Windows but on
64-bit Linux it's 16 bytes. This means len is at a different offset (12 vs 20).
A 32-bit build of your test app should work.

To make this work for 64-bit apps we'll need to convert between native and
win32 versions of this structure.

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

[e-mail] changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |[e-mail]

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

--- Comment #6 from [e-mail] ---
Thanks for looking into it!

Unfortunately 32 bit is not an option for my use case…
This might be unrelated but I also noticed some c# pcap libraries crashing with
a segfault as well when using pinvoke on

int pcap_findalldevs(pcap_if_t **alldevsp, char *errbuf);

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

--- Comment #7 from Hans Leidekker  ---
Created attachment 70729
  --> https://bugs.winehq.org/attachment.cgi?id=70729
patch

Here's a patch that should fix the 64-bit case for pcap_handler().

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

--- Comment #8 from [e-mail] ---
As far as I can tell the patch fixes the length issue and even dumping packages
just works now :)

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

--- Comment #9 from Hans Leidekker  ---
(In reply to marc_aurel from comment #6)
> Unfortunately 32 bit is not an option for my use case…
> This might be unrelated but I also noticed some c# pcap libraries crashing
> with a segfault as well when using pinvoke on
>
> int pcap_findalldevs(pcap_if_t **alldevsp, char *errbuf);

Because pcap_if structures aren't compatible, probably. Feel free to open a new
bug report for this.

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

--- Comment #10 from [e-mail] ---
(In reply to Hans Leidekker from comment #7)
> Created attachment 70729 [details]
> patch
>
> Here's a patch that should fix the 64-bit case for pcap_handler().

I just tested pcap_next and pcap_next and they have the same issue...
Tried fixing it but the program just hangs now

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

--- Comment #11 from [e-mail] ---
Created attachment 70730
  --> https://bugs.winehq.org/attachment.cgi?id=70730
pcap_next and pcap_next_ex patch

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

--- Comment #12 from [e-mail] ---
pcap_dispatch works fine since it uses the same wrap_pcap_handler

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

--- Comment #13 from [e-mail] ---
(In reply to Hans Leidekker from comment #9)
> (In reply to marc_aurel from comment #6)
> > Unfortunately 32 bit is not an option for my use case…
> > This might be unrelated but I also noticed some c# pcap libraries crashing
> > with a segfault as well when using pinvoke on
> >
> > int pcap_findalldevs(pcap_if_t **alldevsp, char *errbuf);
>
> Because pcap_if structures aren't compatible, probably. Feel free to open a
> new bug report for this.

Will try to create a minimal working example for that then

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

--- Comment #14 from Hans Leidekker  ---
(In reply to marc_aurel from comment #10)
> (In reply to Hans Leidekker from comment #7)
> > Created attachment 70729 [details]
> > patch
> >
> > Here's a patch that should fix the 64-bit case for pcap_handler().
>
> I just tested pcap_next and pcap_next and they have the same issue...
> Tried fixing it but the program just hangs now

Yes, I'm working on a patch that should fix all cases.

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

--- Comment #15 from Hans Leidekker  ---
Created attachment 70731
  --> https://bugs.winehq.org/attachment.cgi?id=70731
patch

Can you try these patches?

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

--- Comment #16 from [e-mail] ---
Can confirm that all functions that return a package header are now working
properly, though the c# issue is still present; will open a new bug report
about that soon.

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

Hans Leidekker  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |FIXED
      Fixed by SHA1|                            |a999d57d6a1757078d678a9ab0a
                   |                            |e9734a7f8ecc6

--- Comment #17 from Hans Leidekker  ---
Fixed with a999d57d6a1757078d678a9ab0ae9734a7f8ecc6.

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

--- Comment #18 from [e-mail] ---
*** Bug 51835 has been marked as a duplicate of this bug. ***

[Bug 51818] Reporting packet length is always 0

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51818

Alexandre Julliard  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |CLOSED

--- Comment #19 from Alexandre Julliard  ---
Closing bugs fixed in 6.19.