Basically:
* "classification by-ip" (i.e. `flow->guessed_protocol_id_by_ip` is
NEVER returned in the protocol stack (i.e.
`flow->detected_protocol_stack[]`);
* if the application is interested into such information, it can access
`ndpi_protocol->protocol_by_ip` itself.
There are mainly 4 points in the code that set the "classification
by-ip" in the protocol stack: the generic `ndpi_set_detected_protocol()`/
`ndpi_detection_giveup()` functions and the HTTP/STUN dissectors.
In the unit tests output, a print about `ndpi_protocol->protocol_by_ip`
has been added for each flow: the huge diff of this commit is mainly due
to that.
Strictly speaking, this change is NOT an API/ABI breakage, but there are
important differences in the classification results. For examples:
* TLS flows without the initial handshake (or without a matching
SNI/certificate) are simply classified as `TLS`;
* similar for HTTP or QUIC flows;
* DNS flows without a matching request domain are simply classified as
`DNS`; we don't have `DNS/Google` anymore just because the server is
8.8.8.8 (that was an outrageous behaviour...);
* flows previusoly classified only "by-ip" are now classified as
`NDPI_PROTOCOL_UNKNOWN`.
See #1425 for other examples of why adding the "classification by-ip" in
the protocol stack is a bad idea.
Please, note that IPV6 is not supported :( (long standing issue in nDPI) i.e.
`ndpi_protocol->protocol_by_ip` wil be always `NDPI_PROTOCOL_UNKNOWN` for
IPv6 flows.
Define `NDPI_CONFIDENCE_MATCH_BY_IP` has been removed.
Close#1687
The host automa is used for two tasks:
* protocol sub-classification (obviously);
* DGA evaluation: the idea is that if a domain is present in this
automa, it can't be a DGA, regardless of its format/name.
In most dissectors both checks are executed, i.e. the code is something
like:
```
ndpi_match_host_subprotocol(..., flow->host_server_name, ...);
ndpi_check_dga_name(..., flow->host_server_name,...);
```
In that common case, we can perform only one automa lookup: if we check the
sub-classification before the DGA, we can avoid the second lookup in
the DGA function itself.
* fixed autoconf CFLAGS/LDFLAGS MSAN issue which could lead to build errors
* introduced portable version of gmtime_r aka ndpi_gmtime_r
* do as most as possible of the serialization work in ndpi_utils.c
* use flow2json in ndpiReader
Signed-off-by: lns <matzeton@googlemail.com>
The big change in TLS code is to allow "master" protocols other than
TLS/DTLS, like SMTPS, POPS and IMAPS.
This change will allow, in a future, a proper and complete TLS dissection
for all these protocols with "STARTTLS"-like messages.
Add (basic) internal stats to the main data structures used by the
library; they might be usefull to check how effective these structures
are.
Add an option to `ndpiReader` to dump them; enabled by default in the
unit tests.
This new option enables/disables dumping of "num dissectors calls"
values, too (see b4cb14ec).
Add (basic) internal stats to the main data structures used by the
library; they might be usefull to check how effective these structures
are.
Add an option to `ndpiReader` to dump them; disabled by default to avoid
too much fuss with the unit tests.
* fixed possible memory leak caused by an invalid call to `node_proto_guess_walker()` during serialization
* execute serialization code while running regression tests
Signed-off-by: Toni Uhlig <matzeton@googlemail.com>
* Add some statistics to ndpiReader
The purpose of this version of ndpiReader is too adding some other statistics printed by ndpiReader. In this simple version the domain names(in the flows) that are collected are:
flow-> ssh_tls.server_info
flow-> host_server_name
and are placed in a UT_hash_table, ordering them by number of occurrences.
* Update example/ndpiReader.c
Co-authored-by: Toni <matzeton@googlemail.com>
* Update example/ndpiReader.c
Co-authored-by: Toni <matzeton@googlemail.com>
* Update example/ndpiReader.c
Co-authored-by: Toni <matzeton@googlemail.com>
* Update example/ndpiReader.c
Co-authored-by: Toni <matzeton@googlemail.com>
* Update example/ndpiReader.c
Co-authored-by: Toni <matzeton@googlemail.com>
* Update example/ndpiReader.c
Co-authored-by: Toni <matzeton@googlemail.com>
* Update example/ndpiReader.c
Co-authored-by: Toni <matzeton@googlemail.com>
* Update example/ndpiReader.c
Co-authored-by: Toni <matzeton@googlemail.com>
* Update example/ndpiReader.c
Co-authored-by: Toni <matzeton@googlemail.com>
* Update example/ndpiReader.c
Co-authored-by: Toni <matzeton@googlemail.com>
* Update example/ndpiReader.c
Co-authored-by: Toni <matzeton@googlemail.com>
* Update example/ndpiReader.c
Co-authored-by: Toni <matzeton@googlemail.com>
* Update ndpiReader.c
* Update ndpiReader.c
* Update ndpiReader.c
* Update ndpiReader.c
Co-authored-by: Toni <matzeton@googlemail.com>
* Fixes#1528
* Serialization Interface should also fuzzed
* libjson-c may only be used in the unit test to verify the internal serialization interface
* Serialization Interface supports tlv(broken), csv and json
* Unit test does work again and requires libjson-c
Signed-off-by: lns <matzeton@googlemail.com>
* Removed Visual Studio leftovers. Maintaining an autotools project with VS integration requires some additional overhead.
Signed-off-by: Toni Uhlig <matzeton@googlemail.com>
Signed-off-by: lns <matzeton@googlemail.com>
- partial revert of:
commit 51cfdfb0d8
Author: Luca Deri <deri@ntop.org>
Date: Sun Nov 17 17:51:45 2019 +0100
Removed unused JSON-C code
- Json option is changed from 'j' to 'k' as it's used in the new codebase.
- use HAVE_LIBJSON_C instead of HAVE_JSON_C.
- tabs vs spaces clean ups.
Signed-off-by: Vitaliy Ivanov <vitaliyi@interfacemasters.com>
Conflicts:
example/ndpiReader.c
At every fuzz iteration (i.e for every trace file):
* keep the same ndpi context (`ndpi_init_detection_module` is very
slow);
* reset the flow table, otherwise it grows indefinitely.
This change should fix the "out-of-memory" errors reported by oss-fuzz.
Remove the last uses of `struct ndpi_id_struct`.
That code is not really used and it has not been updated for a very long
time: see #1279 for details.
Correlation among flows is achieved via LRU caches.
This change allows to further reduce memory consumption (see also
91bb77a8).
At nDPI 4.0 (more precisly, at a6b10cf, because memory stats
were wrong until that commit):
```
nDPI Memory statistics:
nDPI Memory (once): 221.15 KB
Flow Memory (per flow): 2.94 KB
```
Now:
```
nDPI Memory statistics:
nDPI Memory (once): 235.27 KB
Flow Memory (per flow): 688 B <--------
```
i.e. memory usage per flow has been reduced by 77%.
Close#1279
This allows to avoid triggering alerts for trusted albeit private certificate issuers.
Extended the example/protos.txt with the new syntax for specifying trusted issueDN.
Example:
trusted_issuer_dn:"CN=813845657003339838, O=Code42, OU=TEST, ST=MN, C=US"
As a general rule, the higher the confidence value, the higher the
"reliability/precision" of the classification.
In other words, this new field provides an hint about "how" the flow
classification has been obtained.
For example, the application may want to ignore classification "by-port"
(they are not real DPI classifications, after all) or give a second
glance at flows classified via LRU caches (because of false positives).
Setting only one value for the confidence field is a bit tricky: more
work is probably needed in the next future to tweak/fix/improve the logic.
Remove some unused fields and re-organize other ones.
In particular:
* Update the parameters of `ndpi_ssl_version2str()` function
* Zattoo, Thunder: these timestamps aren't really used.
* Ftp/mail: these protocols are dissected only over TCP.
* Attention must be paid to TLS.Bittorrent flows to avoid invalid
read/write to `flow->protos.bittorrent.hash` field.
This is the last(?) commit of a long series (see 22241a1d, 227e586e,
730c2360, a8ffcd8b) aiming to reduce library memory consumption.
Before, at nDPI 4.0 (more precisly, at a6b10cf7, because memory stats
were wrong until that commit):
```
nDPI Memory statistics:
nDPI Memory (once): 221.15 KB
Flow Memory (per flow): 2.94 KB
```
Now:
```
nDPI Memory statistics:
nDPI Memory (once): 231.71 KB
Flow Memory (per flow): 1008 B <---------
```
i.e. memory usage per flow has been reduced by 66%, dropping below the
psychological threshold of 1 KB.
To further reduce this value, we probably need to look into #1279:
let's fight this battle another day.
Looking at `struct ndpi_flow_struct` the two bigger fields are
`host_server_name[240]` (mainly for HTTP hostnames and DNS domains) and
`protos.tls_quic.client_requested_server_name[256]`
(for TLS/QUIC SNIs).
This commit aims to reduce `struct ndpi_flow_struct` size, according to
two simple observations:
1) maximum one of these two fields is used for each flow. So it seems safe
to merge them;
2) even if hostnames/SNIs might be very long, in practice they are rarely
longer than a fews tens of bytes. So, using a (single) large buffer is a
waste of memory for all kinds of flows. If we need to truncate the name,
we keep the *last* characters, easing domain matching.
Analyzing some real traffic, it seems safe to assume that the vast
majority of hostnames/SNIs is shorter than 80 bytes.
Hostnames/SNIs are always converted to lowercase.
Attention was given so as to be sure that unit-tests outputs are not
affected by this change.
Because of a bug, TLS/QUIC SNI were always truncated to 64 bytes (the
*first* 64 ones): as a consequence, there were some "Suspicious DGA
domain name" and "TLS Certificate Mismatch" false positives.
We can write to `flow->protos` only after a proper classification.
This issue has been found in Kerberos, DHCP, HTTP, STUN, IMO, FTP,
SMTP, IMAP and POP code.
There are two kinds of fixes:
* write to `flow->protos` only if a final protocol has been detected
* move protocol state out of `flow->protos`
The hard part is to find, for each protocol, the right tradeoff between
memory usage and code complexity.
Handle Kerberos like DNS: if we find a request, we set the protocol
and an extra callback to further parsing the reply.
For all the other protocols, move the state out of `flow->protos`. This
is an issue only for the FTP/MAIL stuff.
Add DHCP Class Identification value to the output of ndpiReader and to
the Jason serialization.
Extend code coverage of fuzz tests.
Close#1343Close#1342
