Commit Graph

18 Commits

Author SHA1 Message Date
Laurent Deniel 2e08b800b4 - add handling of FT_IPv6 variables
there is still some work to do in resolv.c (get_host_ipaddr6)

- add display filters of this kind in packet-ipv6.c just
  for testing (display filtering is incomplete)

svn path=/trunk/; revision=808
1999-10-11 17:05:49 +00:00
Guy Harris 29b9c8a285 Have "get_host_ipaddr()" return a Boolean indicating whether it
succeeded or failed, and, if it succeeded, have it fill in the IP
address if found through a pointer passed as the second argument.

Have it first try interpreting its first argument as a dotted-quad IP
address, with "inet_aton()", and, if that fails, have it try to
interpret it as a host name with "gethostbyname()"; don't bother with
"gethostbyaddr()", as we should be allowed to filter on IP addresses
even if there's no host name associated with them (there's no guarantee
that "gethostbyaddr()" will succeed if handed an IP address with no
corresponding name - and it looks as if FreeBSD 3.2, at least, may not
succeed in that case).

Add a "dfilter_fail()" routine that takes "printf()"-like arguments and
uses them to set an error message for the parse; doing so means that
even if the filter expression is syntactically valid, we treat it as
being invalid.  (Is there a better way to force a parse to fail from
arbitrary places in routines called by the parser?)

Use that routine in the lexical analyzer.

If that error message was set, use it as is as the failure message,
rather than adding "Unable to parse filter string XXX" to it.

Have the code to handle IP addresses and host names in display filters
check whether "get_host_ipaddr()" succeeded or failed and, if it failed,
arrange that the parse fail with an error message indicating the source
of the problem.

svn path=/trunk/; revision=802
1999-10-11 03:03:12 +00:00
Laurent Deniel 8333e3b3cf Fix a typo in error message.
svn path=/trunk/; revision=796
1999-10-09 14:14:53 +00:00
Guy Harris 361fcf26e9 Make "dfilter_error()" available to the lexical analyzer.
Get rid of the declaration of the non-existent "dfilter_yyerror()", and
put in some #defines to work around the fact that the #defines to
replace "yy" with "dfilter_" in the names of Flex-generated and
Yacc-generated routines aren't put into a header file, they're put into
".c" files.

Have it remember the error message it was handed (unless it's Yacc's
boring "parse error" message).

When generating the message to be shown to the user on a parse error,
make it be the "Unable to parse filter string" message, and, if a
non-boring error message was supplied to "dfilter_error()", take that
error message onto the end.

Don't panic if a field type we don't yet support in the parser is seen;
generate an error, telling the user we don't support filter on that type
yet.

Don't assume that "global_df" has been set if we see an empty statement
(if the first token was the end-marker, because, say, the first token
the lexical analyzer found was a field of a type not yet supported in
filter expressions, "global_df" won't have been set).

svn path=/trunk/; revision=783
1999-10-07 21:47:20 +00:00
Gilbert Ramirez 1b7bd2f14b Fix dfilter scanner to accept hyphenated hostnames for IPv4 addresses.
svn path=/trunk/; revision=776
1999-10-06 18:42:40 +00:00
Gilbert Ramirez b73cea0fca Removed dummy protocol and removed bug which prevented the first
registered protocol's name from being used in a display filter.

svn path=/trunk/; revision=766
1999-10-04 18:09:05 +00:00
Gilbert Ramirez bcf4001ef0 Changed (again) the way that the FT_BOOLEAN field type works internally.
Dissector code can add FT_BOOLEAN fields to the proto_tree and pass TRUE
or FALSE values (non-zero and zero values). The display filter language,
however, treats the checking for the existence of a FT_BOOLEAN field as
the checking for its truth. Before this change, packet-tr.c was the only
dissector using FT_BOOLEAN fields, and it only added the field to the
proto_tree if the TRUE; the dissector was determining the difference between
the check for existence and the check for truth.

I made this change because packet-ppp.c added some FT_BOOLEAN fields and
added them to the tree regardless of truth value, It's more natural just to
do it this way and let the display filter code worry about whether to
check for existence or truth. So that's how it works now.

svn path=/trunk/; revision=679
1999-09-15 06:13:21 +00:00
Gilbert Ramirez b53d4ba179 Changed packet-tr.c to insert tr.sr, a FT_BOOLEAN field, only if tr.sr
is true. The test for truth now becomes a test for existence. The dfilter
grammar no longer recognizes 'true' and 'false', since you can now check
a boolean field via:

	tr.sr

or by its negation:

	!tr.sr

svn path=/trunk/; revision=591
1999-08-27 19:27:22 +00:00
Gilbert Ramirez b85bb70925 Changed some symbols inside parser, fixed default error message in
dfilter_compile, and removed debug printf that I left in match_selected.

svn path=/trunk/; revision=532
1999-08-20 21:19:28 +00:00
Gilbert Ramirez 57198bc28f Made handling of byte strings in scanner and parser much simpler,
improving size of grammar and creating the possibility of dfilter_compile
reporting errors back to user. In this case, if an ETHER variable is
compared against a byte string that is not 6 bytes, an error condition is
flagged appropriately. I have not put in the code to conver that error flag
to a message to the user, but that's what I'm working on next.

Also, fixed sample debug session in README to show correct gdb prompt.

svn path=/trunk/; revision=522
1999-08-20 06:01:07 +00:00
Gilbert Ramirez 8030084e93 Modified YACC grammar to use non-yy symbols, to avoid conflicts with
libpcap's that were compiled with symbols beginning with 'yy'.

svn path=/trunk/; revision=487
1999-08-14 06:24:27 +00:00
Gilbert Ramirez ab6490398c Moved global memory alloction used in display filters (which was stored
in dfilter-grammar.y) to a new struct dfilter. Display filters now have
their own struct, rather than simply being GNode's. This allows multiple
display filters to exist at once, aiding John McDermott in his
work on colorization.

svn path=/trunk/; revision=480
1999-08-13 23:47:43 +00:00
Guy Harris a5acc58fe3 Create a "dfilter-int.h" file, containing stuff used internally to the
display filter code but not outside it (and not static to one of the
modules in the display filter code), with most of that stuff moved there
from "dfilter.h".

Add a declaration of "byte_str_to_guint8_array()" to "dfilter-int.h".

svn path=/trunk/; revision=479
1999-08-12 21:16:32 +00:00
Gilbert Ramirez 6c9276f03c One small regex change, just to be safe.
svn path=/trunk/; revision=478
1999-08-12 15:20:18 +00:00
Gilbert Ramirez 336b94f506 Fixed two bugs in display filter parsing.
1. Some IP addresses (like 0.0.0.0) would be interpreted as byte ranges.
2. Parens were being ignored.

Thanks to Guy for pointing these out to me.

svn path=/trunk/; revision=477
1999-08-12 15:10:48 +00:00
Gilbert Ramirez 6a823008b7 Logical operands needed to set the yylval as well as return the
token to the yacc parser.

svn path=/trunk/; revision=446
1999-08-05 16:42:31 +00:00
Gilbert Ramirez aebcf2eb32 Removed the "exists" keyword from the grammar. The name of a protocol or a
field by itself assumes you are checking for the existence of that protocol
or field.

Changed the format of the list of filterable fields in the man page.
Developers: run "./configure" so that your configure script will re-create
dfilter2pod from the new dfilter2pod.in

svn path=/trunk/; revision=426
1999-08-03 15:04:33 +00:00
Gilbert Ramirez b2f932c1db Changed the display filter scanner from GLIB's GScanner to lex. The code
as it standed depends on your lex being flex, but that only matters if you're
a developer. The distribution will include the dfilter-scanner.c file, so
that if the user doesn't modify dfilter-scanner.l, he won't need flex to
re-create the *.c file.

The new lex scanner gives me better syntax checking for ether addresses. I
thought I could get by using GScanner, but it simply wasn't powerful enough.

All operands have English-like abbreviations and C-like syntax:
and, && ; or, || ; eq, == ; ne, != ; , etc.

I removed the ETHER_VENDOR type in favor of letting the user use the [x:y]
notation:	ether.src[0:3] == 0:6:29 instead of ether.srcvendor == 00:06:29

I implemented the IPXNET field type; it had been there before, but was
not implemented. I chose to make it use integer values rather than byte
ranges, since an IPX Network is 4 bytes. So a display filter looks like this:
	ipx.srcnet == 0xc0a82c00
rather than this:
	ipx.srcnet == c0:a8:2c:00

I can supposrt the byte-range type IPXNET in the future, very trivially.

I still have more work to do on the parser though. It needs to check ranges
when extracting byte ranges ([x:y]) from packets. And I need to get rid
of those reduce/reduce errors from yacc!

svn path=/trunk/; revision=414
1999-08-01 04:28:20 +00:00