Apparently, if you have an interface in monitor mode, capturing on the
"any" device can get packets that have a SLL hatype of 803, which is the
ARPHRD_ value for radiotap, and with the payload containing a radiotap
header, followed by an 802.11 header, followed by the 802.11 payload.
Handle that.
Some platforms define the old V7 routine index() (renamed to strchr() in
System V; the latter name is what's used in ANSI C), and you get
"declaration of 'index' shadows a global declaration" warnings.
Call the variable if_index instead.
./print-sll.c: In function ‘sll2_if_print’:
./print-sll.c:419:2: warning: ISO C90 forbids mixed declarations and code [-Wdeclaration-after-statement]
uint32_t index = EXTRACT_BE_U_4(sllp->sll2_if_index);
^~~~~~~~
[skip ci]
Index is displayed always, name only if available.
Warn about possible wrong interfaces when in reading mode
(pcap file can be displayed on a different host then where
was captured) [1].
See: GH the-tcpdump-group/libpcap#127
[1] https://lists.sandelman.ca/pipermail/tcpdump-workers/2018-July/001019.html
Signed-off-by: Petr Vorel <pvorel@suse.cz>
Suggested-by: Guy Harris <guy@alum.mit.edu>
Reviewed-by: Denis Ovsienko <denis@ovsienko.info>
Reviewed-by: Guy Harris <guy@alum.mit.edu>
This can prevent bizarre failures if, for example, you've done a
configuration in the top-level source directory, leaving behind one
config.h file, and then do an out-of-tree build in another directory,
with different configuration options. This way, we always pick up the
same config.h, in the build directory.
Use EXTRACT_U_1() as required by those changes. Remove
no-longer-necessary & operators from other EXTRACT_ calls.
While we're at it, add MAC_ADDR_LEN to netdissect.h, and use it instead
of ETHER_ADDR_LEN; eliminate ETHER_ADDR_LEN.
Move the maximum Ethernet length field value to ethertype.h, under the
name MAX_ETHERNET_LENGTH_VAL.
Move the Ethernet header structure, and the #define for the Ethernet
header length, to print-ether.c; in non-Ethernet dissectors that were
using the Ethernet header structure, just declare two nd_mac_addr
variables for the source and destination MAC addresses and use them
instead of the Ethernet header (we don't need the type field there).
These changes leave nothing in ether.h, so eliminate it.
Now all the macros have a name meaning a count in bytes.
With _S_: signed, _U_: unsigned
e.g.:
EXTRACT_BE_32BITS -> EXTRACT_BE_U_4
EXTRACT_LE_32BITS -> EXTRACT_LE_U_4
...
EXTRACT_BE_INT32 -> EXTRACT_BE_S_4
and have:
EXTRACT_8BITS -> EXTRACT_U_1
EXTRACT_INT8 -> EXTRACT_S_1
If a protocol that runs under a link-layer protocol would print the
link-layer addresses for the packet as source and destination addresses
for the packet, don't have it blithely assume those link-layer addresses
are present or are at a particular offset from the beginning of that
protocol's data; Ethertypes, for example, are used by a number of
protocols, not all of which have Ethernet headers and not all of which
have any MAC headers.
Instead, pass the printers for those protocols structures with a pointer
to the address data and a pointer to a routine that prints the address.
Fixes some heap overflows found with American Fuzzy Lop by Hanno Böck.
with the tag '\summary:' for greping.
Remark: Currently some printers have no summary line.
Moreover:
Summarize all printers with a single line in INSTALL.txt
Have llc_print() return the length of the LLC header, plus the length of
the SNAP header, if available - or, if it couldn't dissect the payload,
return the *negative* of that sum. Use that return value in link-layer
printers.
Don't print LLC header information for SNAP packets; if we have a SNAP
header, just call snap_print() and return its return value, regardless
of whether it's 1 or 0, don't fall into the code to print raw LLC header
information - and don't print it with -e, either.
If llc_print() returns 0, just call the default packet printer, don't
print the MAC-layer header or the extracted ethertype - llc_print() will
print the source and destination MAC addresses and whatever type
information is in the LLC or SNAP headers.
If we don't know the DSAP/LSAP, and it's an information frame (numbered
or not) and not an XID frame, return 0, so that we give a hex dump of
the raw payload.
In addition, print the length when printing SNAP header information with
-e.
The purpose of this macro was to enable the file-by-file switch to NDO,
after which only tcpdump.c had a use of it and the definitions guarded
by it. Update tcpdump.c not to require them any more and dismiss the
unused definitions.
And, as we require at least autoconf 2.61, and as autoconf 2.61 and
later have AC_TYPE_UINTn_T and AC_TYPE_INTn_T macros, we use them to
define the uintN_t and intN_t macros if the system doesn't define them
for us.
This lets us get rid of bitypes.h as well.
Have them take a netdissect_options * argument, and get the "no name
resolution" flag from it.
Move the declaration of dnaddr_string to addrtoname.h, along with the
other XXX-to-string routines.
Both interface.h and netdissect.h include <pcap.h>, thus most files
should not include it regardless if these need it or not. The only
exceptions so far remain:
* addrtoname.c
* missing/datalinks.c
* missing/dlnames.c
* tcpdump.c
Remove lots of $Header's and a few $Id's that all belong to the former
CVS repository of tcpdump itself. These keywords have been frozen since
the migration to git in late 2008.
For headers included in only one source file, put the header contents in
the source file in question, and get rid of a bunch of stuff from the
header not used in the source file.
Make sure all of them are declared const and most of them -- static.
Proper declaration of token arrays is a common review point for new code
that is based on existing decoders. Thus fix the issue at its root.
Instead of having the Ethernet-type handler process the VLAN and Alteon
jumbo frame Ethernet type values, process them in the Ethernet (and
Linux cooked-mode) dissectors. This makes it easier for the right MAC
addresses to be printed for those packets.
As part of that, rename ether_encap_print() to ethertype_print() - it
doesn't print encapsulated Ethernet frames, it prints payloads whose
packet type is indicated by an Ethernet type field value - and remove
the no-longer-needed "extracted Ethernet type" argument. That also lets
us eliminate it from the SNAP print routine.
Make ether_print() take a function, and an argument to pass to that
function, as parameters, so that, for example, the ATM LANE printer can
use it and put the LEC ID into the link-layer headeer printout.
Use the EXTRACT_ macros to extract multi-byte integral values from
packets, rather than just dereferencing pointers into the packet; there
is no guarantee that the packet data will be aligned on the right
boundary, and there is no guarantee that, if they're not, a direct
access will work correctly.
having its callers do so - some of its callers *weren't* doing so,
leaving random junk in that argument in some cases.
When checking for "802.3-encapsulated" IPX, check the raw values of the
SSAP and DSAP for 0xFF, don't check them after the low-order bit has
been masked off.
The "flag" values in the LLC header aren't bits, they're combinations of
bits, including the combination "no bits"; don't use "bittok2str()" on
them. Also, combine the proper bits, namely the C/R bit (which we
weren't combining) and the P/F bit (which we were).
link-layer print routines if no other print routine claimed the packet.
Test whether that flag is set rather than testing whether neither of -x
or -q were specified, and have -x, -q, *and* -X set that flag, so that
-X suppresses it just as -x does. That way you don't get those pckets
dumped twice if -X was specified.