ND_TCHECK_n(e).
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' label(s) and most associated code(s).
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.
Have roundup2() cast the power-of-2 argument to u_int; that way, you
don't have to explicitly define it as an unsigned value in order to
avoid compiler or UBSan complaints about signed integers.
Use it instead of rolling our own rounding-to-a-power-of-2.
We require an environment with a C99-compatible snprintf(), so we don't
need to work around older implementations. Make the configuration
process fail if we don't have snprintf() and vsnprintf().
We require at least VS 2015, so we don't have to check for _MSC_VER >=
1400. Make the build fail if we don't have at least VS 2015.
We apparently do, however, have to use __inline, as the VS 2015
documentation doesn't meaning plain old "inline". Update a comment.
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.
The error was:
print-nfs.c:537:2: runtime error: unsigned integer overflow:
4294967295 + 3 cannot be represented in type 'unsigned int'
print-nfs.c:541:14: runtime error: unsigned integer overflow:
4294967295 + 3 cannot be represented in type 'unsigned int'
Add a test case.
Get rid of the global nfserr variable and, instead, have it be local to
interp_reply(). That means one less global variable, which may be good
if any multi-threaded program tries to use libnetdissect in more than
one thread (there are still global variables that would have to be
removed), and gets rid of some cases where we didn't need to set it.
Don't bundle multiple operations inside an if clause. This squelches
some warnings from MSVC, and makes the code a bit more uniform and a bit
easier to understand (and, in the process of doing that, found a bug
that was fixed in 596aca3d93).
Don't just blast through it and do a single check at the end to make
sure we didn't run past the end of the packet; check for the
fixed-length part of the credentials, then check for the variable-length
part of the credentials, and then do the same two steps for the
verifier.
Fix the checks against the on-the-network length while we're at it.
The functions are: nd_print, nd_printztn, nd_printn and nd_printzp.
Trying to make it clearer that they currently have to be used only on part
of the packet buffer.
Update some comments.
Some versions of the MSVC runtime library have a non-C99-compliant
vsnprintf(), which we want to avoid. On Windows, use snprintf() and
vsnprintf() for VS 2015 and later, where they both exist in
C99-compliant forms, and wrap _{v}snprintf_s() otherwise (they're
guaranteed to do the null termination that we want).
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.
When showing a readdir verifier, using big-endian means that it shows
the verifier as a string of 16 octet values, from the first to the last,
which makes sense, and which means that the way we display it is
independent of the byte order of the host running tcpdump, which is a
Good Thing.
When showing a file handle, the same applies, although one could make a
case for not separating the 4-octet words with colons, and just showing
it as a sequence of octets.
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
Also, put the buffer on the stack; no reason to make it static. (65
bytes isn't a lot.)
This fixes a buffer over-read discovered by Kamil Frankowicz.
Add a test using the capture file supplied by the reporter(s).
Fix the bounds checking for the NFSv3 WRITE procedure to check whether the
length of the opaque data being written is present in the captured data,
not just whether the byte count is present in the captured data.
furthest forward in the packet, not the item before it. (This also lets
us eliminate the check for the "stable" argument being present in the
captured data; rewrite the code to print that to make it a bit clearer.)
Check that the entire ar_stat field is present in the capture.
Note that parse_wcc_attr() is called after we've already checked whether
the wcc_data is present.
Check before fetching the "access" part of the NFSv3 ACCESS results.
This fixes a buffer over-read discovered by Kamil Frankowicz.
Include a test for the "check before fetching the "access" part..." fix,
using the capture supplied by the reporter(s).
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 our own routines to convert between IPv4/IPv6 addresses and
strings; that helps if, for example, we want to build binary versions of
tcpdump for Windows that can run both on NT 5 (W2K/WXP), which doesn't
have inet_ntop() or inet_pton(), and NT 6 (Vista/7/8/10), which do. It
also means that we don't require IPv6 library support on UN*X to print
addresses (if somebody wants to build tcpdump for older UN*Xes lacking
IPv6 support in the system library or in add-on libraries).
Get rid of files in the missing directory that we don't need, and
various no-longer-necessary autoconf tests.
