Builds using Autotools or CMake generate config.h, thus remove the
'#ifdef HAVE_CONFIG_H'/'#endif'.
Remove also the 'add_definitions(-DHAVE_CONFIG_H)' in CMakeLists.txt.
Apply this to the 4 the recently converted protocols.
HOW TO USE:
Define this in a print-*.c file before including netdissect.h to make
all its ND_TCHECK*() instances longjmp(). Only do this after verifying
that every ND_TCHECK*() in the file is correct and that in every
possible case it is safe to call longjmp() without incurring resource
leaks or any other problems. If it is not safe or feasible to convert
whole file, consider converting one function at a time.
The change made in commit bdd97f54 was safe, but was slightly incorrect.
Before the change the decoder used the _declared_ end of packet (the
initial "cp" + the initial "len") as the target of how much data to try
to decode, and whilst trying to do that it could cross the _captured_ end
of packet (ndo_snapend) and give up complaining, so the output would
correctly indicate there was supposed to be more data beyond the
unexpected snapshot end.
After the change the decoder started to use the captured end of packet to
tell where the packet ends, so it would never cross ndo_snapend, but it
would interpret the packet data as if the missing part was never supposed
to be there and would thus decode truncated packets incorrectly.
In order to eliminate this space for misinterpretation, remove the "ep"
pointer and change the code both to advance "cp" and to decrease "len" as
it is going through the protocol structures, so the part of the packet
that is supposed to be present but has not been decoded yet can be
addressed by just "cp" and "len" (like it is done in many functions
elsewhere). Let the GET_ macros guard the snapshot end and use nd_trunc()
to handle the remaining ND_TCHECK_LEN() instances.
Articulate the part of the message sized by skipCount.
Remove a number of instances that do not match common patterns and have
the only substantial effect on the code flow that a truncated packet
triggers "goto trunc" instead of longjmp(). (In a few cases this change
can increase the number of fields printed before giving up.)
ND_TCHECK_n(e), n in { 1, 2, 3, 4, 8 }.
They are redundant because they are followed by a GET_.*_n(e) call,
same n, same e, which do the bounds check.
Remove unused 'trunc' labels and most associated codes.
Update the outputs of some tests accordingly.
Replace more calls to ipaddr_string()/ip6addr_string() with calls to
GET_IPADDR_STRING()/GET_IP6ADDR_STRING() macros performing bounds
checking.
Add similar bounds-checking inline functions and macros to wrap
linkaddr_string(), etheraddr_string(), and isonsap_string() and convert
calls to them to use the macros as well.
Shuffle the inline functions in addrtoname.h around a bit, so that the
inline functions, external declarations, and macros are all in the same
order.
The exceptions are currently:
Some EXTRACT_ in print-juniper.c, not used on packet buffer pointer.
An EXTRACT_BE_U_3 in addrtoname.c, not always used on packet buffer
pointer.
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
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.
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.
tcpdump used to print an empty line for a Loopback (CTP) packet, which
many Cisco switches send by default every 10 seconds. This commit adds
a decoder for the protocol and a test case, which uses the sample
capture from Wireshark wiki (configuration_test_protocol_aka_loop.pcap).
