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8087 Commits

Author SHA1 Message Date
Douglas Bagnall
44a44005a6 compression/huffman: debug function bails upon disaster (CID 1517261)
We shouldn't get a node with a zero code, and there's probably nothing
to do but stop.

   CID 1517261 (#1-2 of 2): Bad bit shift operation
   (BAD_SHIFT)11. negative_shift: In expression j >> offset - k,
   shifting by a negative amount has undefined behavior. The shift
   amount, offset - k, is -3.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Jeremy Allison <jra@samba.org>

Autobuild-User(master): Jeremy Allison <jra@samba.org>
Autobuild-Date(master): Mon Dec 19 23:29:04 UTC 2022 on sn-devel-184
2022-12-19 23:29:04 +00:00
Douglas Bagnall
628f14c149 compression/huffman: double check distance in matches (CID 1517278)
Because we just wrote the intermediate representation to have no zero
distances, we can be sure it doesn't, but Coverity doesn't know. If
distance is zero, `bitlen_nonzero_16(distance)` would be bad.

   CID 1517278 (#1 of 1): Bad bit shift operation
   (BAD_SHIFT)41. large_shift: In expression 1 << code_dist, left
   shifting by more than 31 bits has undefined behavior. The shift
   amount, code_dist, is 65535.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-19 22:32:35 +00:00
Douglas Bagnall
6b4d94c987 compression: fix sign extension of long matches (CID 1517275)
Very long matches would be written instead as very very long matches.

We can't in fact hit this because we have a MAX_MATCH_LENGTH defined
as 64M, but if we could, it might make certain 2GB+ strings impossible
to compress.

  CID 1517275 (#1 of 1): Unintended sign extension
  (SIGN_EXTENSION)sign_extension: Suspicious implicit sign extension:
  intermediate[i + 2UL] with type uint16_t (16 bits, unsigned) is
  promoted in intermediate[i + 2UL] << 16 to type int (32 bits, signed),
  then sign-extended to type unsigned long (64 bits, unsigned). If
  intermediate[i + 2UL] << 16 is greater than 0x7FFFFFFF, the upper bits
  of the result will all be 1.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-19 22:32:35 +00:00
Douglas Bagnall
baba440ffa compression tests: avoid div by zero in failure (CID 1517297)
Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-19 22:32:35 +00:00
Douglas Bagnall
b99e0e9301 compression/tests: calm the static analysts (CID: numerous)
None of our test vectors are 18446744073709551615 bytes long, which
means we can know an `expected_length == returned_length` check will
catch the case where the compression function returns -1 for error. We
know that, but Coverity doesn't.

It's the same thing over and over again, in two different patterns:

>>>     CID 1517301:  Memory - corruptions  (OVERRUN)
>>>     Calling "memcmp" with "original.data" and "original.length" is
suspicious because of the very large index, 18446744073709551615. The index
may be due to a negative parameter being interpreted as unsigned.
393     	if (original.length != decomp_written ||
394     	    memcmp(decompressed.data,
395     		   original.data,
396     		   original.length) != 0) {
397     		debug_message("\033[1;31mgot %zd, expected %zu\033[0m\n",
398     			      decomp_written,

*** CID 1517299:  Memory - corruptions  (OVERRUN)
/lib/compression/tests/test_lzxpress_plain.c: 296 in
test_lzxpress_plain_decompress_more_compressed_files()
290     		debug_start_timer();
291     		written = lzxpress_decompress(p.compressed.data,
292     					      p.compressed.length,
293     					      dest,
294     					      p.decompressed.length);
295     		debug_end_timer("decompress", p.decompressed.length);
>>>     CID 1517299:  Memory - corruptions  (OVERRUN)
>>>     Calling "memcmp" with "p.decompressed.data" and
"p.decompressed.length" is suspicious because of the very large index,
18446744073709551615. The index may be due to a negative parameter being
interpreted as unsigned.
296     		if (written == p.decompressed.length &&
297     		    memcmp(dest, p.decompressed.data, p.decompressed.length)
== 0) {
298     			debug_message("\033[1;32mdecompressed %s!

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-19 22:32:35 +00:00
Douglas Bagnall
d6a67908e1 compression/huffman: check again for invalid codes (CID 1517302)
We know that code is non-zero, because it comes from the combination of
the intermediate representation and the symbol tables that were generated
at the same time. But Coverity doesn't know that, and it thinks we could
be doing undefined things in the subsequent shift.

    CID 1517302:  Integer handling issues  (BAD_SHIFT)
    In expression "1 << code_bit_len", shifting by a negative amount has

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-19 22:32:35 +00:00
Douglas Bagnall
27af27f901 compression/huffman: tighten bit_len checks (fix SUSE -O3 build)
The struct write_context bit_len attribute is always between 0 and 31,
but if the next patches are applied without this, SUSE GCC -O3 will
worry thusly:

 ../../lib/compression/lzxpress_huffman.c: In function
  ‘lzxpress_huffman_compress’:
 ../../lib/compression/lzxpress_huffman.c:953:5: error: assuming signed
  overflow does not occur when simplifying conditional to constant
  [-Werror=strict-overflow]
   if (wc->bit_len > 16) {
         ^
         cc1: all warnings being treated as errors

Inspection tell us that the invariant holds. Nevertheless, we can
safely use an unsigned type and insist that over- or under- flow is
bad.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-19 22:32:35 +00:00
Douglas Bagnall
e7489be7be fuzz: fix lzxpress plain round-trip fuzzer
The 'compressed' string can be about 9/8 the size of the decompressed
string, but we didn't allow enough memory in the fuzz target for that.
Then when it failed, we didn't check.

Credit to OSSFuzz.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-19 22:32:35 +00:00
Douglas Bagnall
6f77b376d4 compression/huffman: avoid semi-defined behaviour in decompress
We had

               output[output_pos - distance];

where output_pos and distance are size_t and distance can be greater
than output_pos (because it refers to a place in the previous block).

The underflow is defined, leading to a big number, and when
sizeof(size_t) == sizeof(*uint8_t) the subsequent overflow works as
expected. But if size_t is smaller than a pointer, bad things will
happen.

This was found by OSSFuzz with
'UBSAN_OPTIONS=print_stacktrace=1:silence_unsigned_overflow=1'.

Credit to OSSFuzz.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-19 22:32:35 +00:00
Günther Deschner
39e8489dfc s3-librpc: add ads.idl and convert ads_struct to talloc.
Guenther

Signed-off-by: Guenther Deschner <gd@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-16 20:38:32 +00:00
Volker Lendecke
bb94ec2655 tdb: Move 160 bytes from R/W data segment to R/O text
The linker has to relocate the pointers in the array at startup, save
that. I know we have bigger .data blobs, but every bit counts :-)

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-15 21:52:34 +00:00
Volker Lendecke
300ad4ff12 lib: Save intermediate NULL checks with talloc_asprintf_addbuf()
Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-14 04:32:34 +00:00
Volker Lendecke
cbcf7f0d21 lib: Use talloc_asprintf_addbuf() in rdn_name_add()
Add implicit NULL checks

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-14 04:32:34 +00:00
Volker Lendecke
ffba59b5c0 lib: Use talloc_asprintf_addbuf() in ldb_module_call_chain()
This was exactly what talloc_asprintf_addbuf() does.

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-14 04:32:34 +00:00
Volker Lendecke
fe8895c83c lib: Use talloc_asprintf_addbuf() in print_socket_options()
With the proper NULL checks we don't need the stackframe,
use a passed in context instead.

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-14 04:32:34 +00:00
Volker Lendecke
bcdbe6ef6b lib: Use talloc_asprintf_addbuf() in ldif_write_prefixMap()
The first call of talloc_asprintf_append() did not have a NULL check.

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-14 04:32:34 +00:00
Volker Lendecke
c692b5c95b lib: Use talloc_asprintf_addbuf() in str_list_join_shell()
This adds proper NULL checks via talloc_asprintf_addbuf()

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-14 04:32:34 +00:00
Volker Lendecke
2c7766c28f lib: Use talloc_asprintf_addbuf() in str_list_join()
This adds intermediate NULL checks via talloc_asprintf_addbuf()

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-14 04:32:34 +00:00
Volker Lendecke
101396ab76 lib: Use talloc_asprintf_addbuf() in debug.c
Slightly simplify debug_list_class_names_and_levels()

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-14 04:32:34 +00:00
Volker Lendecke
ccb5bafe93 lib: Move talloc_asprintf_addbuf() to talloc
I wanted to use this in debug.c, but this would have meant to pollute
debug's deps with a lot of stuff. Also, looking through uses of
talloc_asprint_append(), very many of those don't do NULL checks
properly and could benefit from the _addbuf() flavor. We can add a
vasprintf variant later if the need shows up.

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-14 04:32:34 +00:00
Volker Lendecke
7870e82cb4 lib: Fix whitespace
Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-14 04:32:34 +00:00
Ralph Boehme
969e062724 lib/util: use process_set_title() in tfork()
Signed-off-by: Ralph Boehme <slow@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-14 01:38:29 +00:00
Ralph Boehme
19c82c19c0 lib/util: add process_set_title()
Signed-off-by: Ralph Boehme <slow@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-14 01:38:29 +00:00
Stefan Metzmacher
36d0a49515 CVE-2022-37966 param: Add support for new option "kdc supported enctypes"
This allows admins to disable enctypes completely if required.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=15237

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
2022-12-13 13:07:30 +00:00
Stefan Metzmacher
fa64f8fa8d CVE-2022-37966 param: let "kdc default domain supportedenctypes = 0" mean the default
In order to allow better upgrades we need the default value for smb.conf to the
same even if the effective default value of the software changes in future.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=15237

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
2022-12-13 13:07:30 +00:00
Stefan Metzmacher
7504a4d6fe CVE-2022-37966 param: don't explicitly initialize "kdc force enable rc4 weak session keys" to false/"no"
This is not squashed in order to allow easier backports...

BUG: https://bugzilla.samba.org/show_bug.cgi?id=15237

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
2022-12-13 13:07:30 +00:00
Stefan Metzmacher
16b805c8f3 CVE-2022-37966 lib/krb5_wrap: no longer reference des encryption types
We no longer have support for des encryption types in the kerberos
libraries anyway.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=15237

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
2022-12-13 13:07:30 +00:00
Stefan Metzmacher
c9b10ee32c CVE-2022-37966 lib/krb5_wrap: remove unused ifdef HAVE_ENCTYPE_AES*
aes encryption types are always supported.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=15237

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
2022-12-13 13:07:30 +00:00
Andrew Bartlett
ee18bc29b8 CVE-2022-37966 param: Add support for new option "kdc force enable rc4 weak session keys"
Pair-Programmed-With: Joseph Sutton <josephsutton@catalyst.net.nz>

Signed-off-by: Andrew Bartlett <abartlet@samba.org>
Signed-off-by: Joseph Sutton <josephsutton@catalyst.net.nz>
Reviewed-by: Stefan Metzmacher <metze@samba.org>
2022-12-13 13:07:29 +00:00
Joseph Sutton
d861d4eb28 CVE-2022-37966 param: Add support for new option "kdc default domain supportedenctypes"
This matches the Windows registry key

HKEY_LOCAL_MACHINE\System\CurrentControlSet\services\KDC\DefaultDomainSupportedEncTypes

BUG: https://bugzilla.samba.org/show_bug.cgi?id=15237

Pair-Programmed-With: Andrew Bartlett <abartlet@samba.org>

Signed-off-by: Joseph Sutton <josephsutton@catalyst.net.nz>
Signed-off-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>
2022-12-13 13:07:29 +00:00
Stefan Metzmacher
7732a4b0bd CVE-2022-38023 docs-xml/smbdotconf: add "server schannel require seal[:COMPUTERACCOUNT]" options
BUG: https://bugzilla.samba.org/show_bug.cgi?id=15240

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>
2022-12-13 13:07:29 +00:00
Stefan Metzmacher
c8e53394b9 CVE-2022-38023 docs-xml/smbdotconf: change 'reject md5 clients' default to yes
AES is supported by Windows Server >= 2008R2, Windows (Client) >= 7 and Samba >= 4.0,
so there's no reason to allow md5 clients by default.
However some third party domain members may need it.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=15240

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>
2022-12-13 13:07:29 +00:00
Stefan Metzmacher
1c6c112990 CVE-2022-38023 docs-xml/smbdotconf: change 'reject md5 servers' default to yes
AES is supported by Windows >= 2008R2 and Samba >= 4.0 so there's no
reason to allow md5 servers by default.

Note the change in netlogon_creds_cli_context_global() is only cosmetic,
but avoids confusion while reading the code. Check with:

 git show -U35 libcli/auth/netlogon_creds_cli.c

BUG: https://bugzilla.samba.org/show_bug.cgi?id=15240

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>
2022-12-13 13:07:29 +00:00
Volker Lendecke
1625dc4b56 tsocket: Fix the build on FreeBSD
FreeBSD does not have TCP_USER_TIMEOUT

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-12 21:16:33 +00:00
Ralph Boehme
8d58174cdd lib/torture: fix tctx arg usage in torture_assert_nttime_equal() macro
Signed-off-by: Ralph Boehme <slow@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-09 23:11:38 +00:00
Ralph Boehme
8a2c763d26 lib/cmdline/tests: add missing includes
Signed-off-by: Ralph Boehme <slow@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
2022-12-09 23:11:38 +00:00
Anoop C S
0c2146eb00 lib/compression: Include missing stat header file
<sys/stat.h> was missing from compression library tests which resulted
in the following compile time error:

../../lib/compression/tests/test_lzx_huffman.c: In function
                                                   ‘datablob_from_file’:
../../lib/compression/tests/test_lzx_huffman.c:383:21: error:
                                         storage size of ‘s’ isn’t known
  383 |         struct stat s;
      |                     ^
../../lib/compression/tests/test_lzx_huffman.c:389:15: warning:
    implicit declaration of function ‘fstat’ [-Wimplicit-function-declaration]
  389 |         ret = fstat(fileno(fh), &s);
      |               ^~~~~

Signed-off-by: Anoop C S <anoopcs@samba.org>
Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Volker Lendecke <vl@samba.org>

Autobuild-User(master): Volker Lendecke <vl@samba.org>
Autobuild-Date(master): Tue Dec  6 11:39:16 UTC 2022 on sn-devel-184
2022-12-06 11:39:16 +00:00
Andreas Schneider
a451fa5ef9 lib:compression: Initialize variables
lib/compression/tests/test_lzx_huffman.c: In function ‘test_lzxpress_huffman_overlong_matches’:
lib/compression/tests/test_lzx_huffman.c:1013:35: error: ‘j’ may be used uninitialized [-Werror=maybe-uninitialized]
 1013 |         assert_int_equal(score, i * j);
      |                                   ^
lib/compression/tests/test_lzx_huffman.c:979:19: note: ‘j’ was declared here
  979 |         size_t i, j;
      |                   ^
lib/compression/tests/test_lzx_huffman.c: In function ‘test_lzxpress_huffman_overlong_matches_abc’:
lib/compression/tests/test_lzx_huffman.c:1059:39: error: ‘k’ may be used uninitialized [-Werror=maybe-uninitialized]
 1059 |         assert_int_equal(score, i * j * k);
      |                                       ^
lib/compression/tests/test_lzx_huffman.c:1020:22: note: ‘k’ was declared here
 1020 |         size_t i, j, k;
      |                      ^
lib/compression/tests/test_lzx_huffman.c:1059:35: error: ‘j’ may be used uninitialized [-Werror=maybe-uninitialized]
 1059 |         assert_int_equal(score, i * j * k);
      |                                   ^
lib/compression/tests/test_lzx_huffman.c:1020:19: note: ‘j’ was declared here
 1020 |         size_t i, j, k;
      |                   ^

Signed-off-by: Andreas Schneider <asn@samba.org>
Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>

Autobuild-User(master): Andreas Schneider <asn@cryptomilk.org>
Autobuild-Date(master): Sun Dec  4 09:12:30 UTC 2022 on sn-devel-184
2022-12-04 09:12:30 +00:00
Douglas Bagnall
d9c192546f lib/compression/lzxpress: fix our slow compression
This uses the same hash table method as lzxpress_huffman, though the
code can't be directly reused as the sizes of the offsets is
different, and there is not a block processing step here.

This will worsen the compression ratio compared to the exhaustive
search we previously used, though we still perform better than
Windows. To put numbers on it, the test files used to compress to 0.91
of Windows' compression size, and now they compress to 0.96.

On the other hand this is many orders of magnitude faster. It is
difficult to say exactly how much faster -- while the testsuite time
has only improved 200-fold (from 7 minutes to 2 seconds), most of the
remaining 2 seconds is used in data generation and management, not
compression. OSSFuzz consistently finds new vectors that time out
after a minute; on these we'll see nearly an order of magnitude of
orders of magnitude inprovement.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>

Autobuild-User(master): Joseph Sutton <jsutton@samba.org>
Autobuild-Date(master): Fri Dec  2 00:00:04 UTC 2022 on sn-devel-184
2022-12-02 00:00:04 +00:00
Douglas Bagnall
caa643e36e lib/compression/lzxpress: shift encoding into helper functions
This makes it easier to rework the encoding decision to depend on a
hash table match rather than the current exhaustive search.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
2022-12-01 22:56:40 +00:00
Douglas Bagnall
fb35cf29a4 lib/compression/lzxpress compression: use a write context struct
This will make it possible to move encoding operations into helper
functions, which will make it easier to restructure the code to use a
hash table for faster matching.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
2022-12-01 22:56:40 +00:00
Douglas Bagnall
e4066b2be6 lib/compression: more tests for lzxpress plain compression
These are based on (i.e. copied and pasted from) the LZ77 + Huffman
tests.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
2022-12-01 22:56:40 +00:00
Douglas Bagnall
ce7ea07d07 testdata: move compression examples to re-use with lzxpress plain
Everything that is in testdata/compression/lzxpress-huffman/ can also
be used for lzxpress plain tests, which is something we really need.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
2022-12-01 22:56:40 +00:00
Douglas Bagnall
9589f5282b lib/compression/lzx-plain: relax size requirements on long file
We are going to change from a slow exact match algorithm to a fast
heuristic search that will not always get the same results as the
exhaustive search.

To be precise, a million zeros will compress to 112 rather than 93 bytes.

We don't insist on an exact size, because that is not an issue here.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
2022-12-01 22:56:39 +00:00
Douglas Bagnall
c2db7fda4e lib/comression: convert test_lzxpress_plain to cmocka
Mainly so I can go

 make bin/test_lzxpress_plain && bin/test_lzxpress_plain
 valgrind bin/test_lzxpress_plain
 rr bin/test_lzxpress_plain
 rr replay

in a tight loop.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
2022-12-01 22:56:39 +00:00
Douglas Bagnall
e5f9deed0d lib/compression: add test scripts README
Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
2022-12-01 22:56:39 +00:00
Douglas Bagnall
1a3d8da731 lib/compression: test util to generate fuzzing seeds
Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
2022-12-01 22:56:39 +00:00
Douglas Bagnall
6a7c0ca23c lib/compression: Windows utility to generate test vectors
If compiled on Windows using Cygwin, MSYS2, or similar, this will output
compressed versions of files exactly as specified by MZ-XCA, if the
following conditions are met:

1. The file > 300 bytes.
2. The compressed file is smaller than the decompressed file.

Otherwise it returns the data unchanged. Without warning; that's just
how the API works.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
2022-12-01 22:56:39 +00:00
Douglas Bagnall
7804570a37 lib/compression: script to test 3 byte hash
Compression uses a 3 byte hash remember LZ77 matches in a 14-bit table.
This script runs the hash over all 16M combinations, then again over
all ASCII combinations, counting collisions to find hot-spots.

If you think you have a better hash, you are probably right, but you
should try it here -- alter h() -- before committing to it. This one is
literally the first one I thought of.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
2022-12-01 22:56:39 +00:00
Douglas Bagnall
dadecede54 lib/compression: helper script to make unbalanced data
Huffman tree re-quantisation and perhaps other code paths are only
triggered by pathological data like this.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
2022-12-01 22:56:39 +00:00