... with the ND_TCHECK_SIZE() macro.
The ND_TCHECK_SIZE() macro is defined by:
#define ND_TCHECK_SIZE(p) ND_TCHECK_LEN(p, sizeof(*(p)))
Example (in print-pptp.c):
struct pptp_msg_sccrp {
[...]
nd_byte hostname[64];
[...]
}
nd_byte is defined in netdissect.h:
typedef unsigned char nd_byte;
ptr is defined as: struct pptp_msg_sccrp *ptr.
As pointer values, ptr->hostname and &ptr->hostname are the same. Thus
the first parameter of ND_TCHECK_LEN() is the same with or without '&'.
When doing:
ND_TCHECK_SIZE(ptr->hostname);
The sizeof(*(p)) gives sizeof(*(ptr->hostname)),
Thus sizeof(unsigned char) is 1.
The check is wrong.
When doing:
ND_TCHECK_SIZE(&ptr->hostname);
The sizeof(*(p)) gives sizeof(*(&ptr->hostname)),
Thus sizeof(unsigned char [64]) is 64.
The check is right.
Thus, when using ND_TCHECK_SIZE with a nd_byte type array struct member,
we need the '&'.
This change revert partially 1b081ef03b.
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.
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
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
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.
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 each decoder that has more than one instance of truncation signaling
and prints the same string in each instance make sure that the string is
declared as "static const char tstr[]" right after the initial includes
block. Where necessary, replace fputs(s, stdout) with equivalent
printf("%s", s).
appropriately, and that GNUmakefile and the MSVC++ project file define
it apppriately, as we do with libpcap, rather than defining it in
"interface.h".
Undo the rcsid-shuffling and addition of extra #includes, as we no
longer need to arrange that "interface.h" be included before using _U_
in an RCS ID or copyright.
use "_U_" in the definitions of "rcsid[]", to eliminate
complaints about those variables being unused;
move the definitions after the include of "interface.h", or add
an include of "interface.h", so that "_U_" is defined.
Include "config.h" before including "tcpdump-stdinc.h" in
"missing/datalinks.c".
compile with Sun C, as "interface.h" isn't being included before the
structures are being declared.
Furthermore, in the files that Sun C *can* compile, it doesn't cause Sun
C to generate code that's safe with unaligned accesses, as
"__attribute__" is defined as a do-nothing macro with compilers that
don't support it.
Therefore, we get rid of that tag on the structures to which it was
added, and instead use "EXTRACT_16BIT()" and "EXTRACT_32BIT()" to fetch
16-bit and 32-bit big-endian quantities from packets. We also fix some
other references to multi-byte quantities to get rid of code that tries
to do unaligned loads on platforms that don't support them.
We also throw in a hack that makes those macros use
"__attribute__((packed))" on structures containing only one 16-bit or
32-bit integer to get the compiler to generate unaligned-safe code
rather than doing it by hand. (GCC on SPARC produces the same code that
doing it by hand does; I don't know if GCC on any other big-endian
strict-alignment processor generates better code for that case. On
little-endian processors, as "ntohs()" and "ntohl()" might be functions,
that might actually produce worse code.)
Fix some places to use "%u" rather than "%d" to print unsigned
quantities.
unused-parameter problems reported by GCC. Add an _U_ tag to label
parameters as unused if the function is called through a pointer (so
that you can't change its signature by removing parameters) or if there
are unused parameters only because the function isn't complete.
Add some additional bounds checks the necessity for which was revealed
while cleaning up unused-parameter problems.
Make some routines static.
"lcp_print()", defined in "print-lcp.c", isn't called anywhere -
"print-ppp.c" has the code to dissect LCP. Get rid of "print-lcp.c".
From Neil T. Spring: fixes for many of those warnings:
addrtoname.c, configure.in: Linux needs netinet/ether.h for
ether_ntohost
print-*.c: change char *foo = "bar" to const char *foo = "bar"
to appease -Wwrite-strings; should affect no run-time behavior.
print-*.c: make some variables unsigned.
print-bgp.c: plen ('prefix len') is unsigned, no reason to
validate by comparing to zero.
print-cnfp.c, print-rx.c: use intoa, provided by addrtoname,
instead of inet_ntoa.
print-domain.c: unsigned int l; (l=foo()) < 0 is guaranteed to
be false, so check for (u_int)-1, which represents failure,
explicitly.
print-isakmp.c: complete initialization of attrmap objects.
print-lwres.c: "if(x); print foo;" seemed much more likely to be
intended to be "if(x) { print foo; }".
print-smb.c: complete initialization of some structures.
In addition, add some fixes for the signed vs. unsigned comparison
warnings:
extract.h: cast the result of the byte-extraction-and-combining,
as, at least for the 16-bit version, C's integral promotions
will turn "u_int16_t" into "int" if there are other "int"s
nearby.
print-*.c: make some more variables unsigned, or add casts to an
unsigned type of signed values known not to be negative, or add
casts to "int" of unsigned values known to fit in an "int", and
make other changes needed to handle the aforementioned variables
now being unsigned.
print-isakmp.c: clean up the handling of error/status indicators
in notify messages.
print-ppp.c: get rid of a check that an unsigned quantity is >=
0.
print-radius.c: clean up some of the bounds checking.
print-smb.c: extract the word count into a "u_int" to avoid the
aforementioned problems with C's integral promotions.
print-snmp.c: change a check that an unsigned variable is >= 0
to a check that it's != 0.
Also, fix some formats to use "%u" rather than "%d" for unsigned
quantities.
