Mirror/zeek
1
0
Fork 0
mirror of https://github.com/zeek/zeek.git synced 2025-10-01 22:28:20 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 1

smb2/read: Parse only 1 byte for data_offset, ignore reserved1

Browse source 
A user provided a SMB2 pcap with the reserved1 field of a ReadResponse
set to 1 instead of 0. This confused the padding computation due to
including this byte into the offset. Properly split data_offset and
reserved1 into individual byte fields.

Closes #4730
This commit is contained in:
Arne Welzel 2025-08-08 15:42:15 +02:00
parent 13f613eb1d
commit b2a2ad7e10
5 changed files with 26 additions and 2 deletions
Download patch file Download diff file Expand all files Collapse all files

5
src/analyzer/protocol/smb/smb2-com-read.pac
View file

@ -93,10 +93,11 @@ type SMB2_read_request(header: SMB2_Header) = record {
type SMB2_read_response(header: SMB2_Header) = record {
structure_size : uint16;
data_offset : uint16;
data_offset : uint8;
reserved1 : uint8;
data_len : uint32;
data_remaining : uint32;
reserved : uint32;
reserved2 : uint32;
pad : padding to data_offset - header.head_length;
data : bytestring &length=data_len;
} &let {

11
testing/btest/Baseline/scripts.base.protocols.smb.smb2-read-response-non-zero-reserved1/files.log Normal file
View file

@ -0,0 +1,11 @@
### BTest baseline data generated by btest-diff. Do not edit. Use "btest -U/-u" to update. Requires BTest >= 0.63.
#separator \x09
#set_separator ,
#empty_field (empty)
#unset_field -
#path files
#open XXXX-XX-XX-XX-XX-XX
#fields ts fuid uid id.orig_h id.orig_p id.resp_h id.resp_p source depth analyzers mime_type filename duration local_orig is_orig seen_bytes total_bytes missing_bytes overflow_bytes timedout parent_fuid
#types time string string addr port addr port string count set[string] string string interval bool bool count count count count bool string
XXXXXXXXXX.XXXXXX FmcSEk2dq4v0hewpM4 CHhAvVGS1DHFjwGM9 172.31.112.17 57829 172.31.112.16 445 SMB 0 (empty) text/plain Test.txt 0.000000 T F 189 189 0 0 F -
#close XXXX-XX-XX-XX-XX-XX

3
testing/btest/Traces/README
View file

@ -53,3 +53,6 @@ Trace Index/Sources:
- ldap/adduser1.pcap ldap/adduser1-ntlm.pcap
Provided by Mohan-Dhawan on #4275
https://github.com/zeek/zeek/issues/4275
- smb_v2_only_non_zero_reserved1.pcap
Provided by @predator89090 on #4730
https://github.com/zeek/zeek/issues/4730

BIN
testing/btest/Traces/smb/smb_v2_only_non_zero_reserved1.pcap Normal file
View file

Binary file not shown.

9
testing/btest/scripts/base/protocols/smb/smb2-read-response-non-zero-reserved1.test Normal file
View file

@ -0,0 +1,9 @@
# @TEST-DOC: Regression test for #4730, ReadResponse not parsed properly.
#
# @TEST-EXEC: zeek -b -C -r $TRACES/smb/smb_v2_only_non_zero_reserved1.pcap %INPUT
# @TEST-EXEC: btest-diff files.log
# @TEST-EXEC: test ! -f analyzer.log
# @TEST-EXEC: test ! -f weird.log
@load base/protocols/smb