The idea is to remove the limitation of only two protocols ("master" and
"app") in the flow classifcation.
This is quite handy expecially for STUN flows and, in general, for any
flows where there is some kind of transitionf from a cleartext protocol
to TLS: HTTP_PROXY -> TLS/Youtube; SMTP -> SMTPS (via STARTTLS msg).
In the vast majority of the cases, the protocol stack is simply
Master/Application.
Examples of real stacks (from the unit tests) different from the standard
"master/app":
* "STUN.WhatsAppCall.SRTP": a WA call
* "STUN.DTLS.GoogleCall": a Meet call
* "Telegram.STUN.DTLS.TelegramVoip": a Telegram call
* "SMTP.SMTPS.Google": a SMTP connection to Google server started in
cleartext and updated to TLS
* "HTTP.Google.ntop": a HTTP connection to a Google domain (match via
"Host" header) and to a ntop server (match via "Server" header)
The logic to create the stack is still a bit coarse: we have a decade of
code try to push everything in only ywo protocols... Therefore, the
content of the stack is still **highly experimental** and might change
in the next future; do you have any suggestions?
It is quite likely that the legacy fields "master_protocol" and
"app_protocol" will be there for a long time.
Add some helper to use the stack:
```
ndpi_stack_get_upper_proto();
ndpi_stack_get_lower_proto();
bool ndpi_stack_contains(struct ndpi_proto_stack *s, u_int16_t proto_id);
bool ndpi_stack_is_tls_like(struct ndpi_proto_stack *s);
bool ndpi_stack_is_http_like(struct ndpi_proto_stack *s);
```
Be sure new stack logic is compatible with legacy code:
```
assert(ndpi_stack_get_upper_proto(&flow->detected_protocol.protocol_stack) ==
ndpi_get_upper_proto(flow->detected_protocol));
assert(ndpi_stack_get_lower_proto(&flow->detected_protocol.protocol_stack) ==
ndpi_get_lower_proto(flow->detected_protocol));
```
- Changed ndpi_flow_info: replaced fixed-size char arrays (always INET6_ADDRSTRLEN) for src_name and dst_name with char* pointers.
- Now IPv4 flows use only INET_ADDRSTRLEN when needed, instead of always reserving IPv6 size.
Call ndpi_stats_reset() once per thread instead of once per flow root
Moved ndpi_stats_reset() outside the loop that destroys ndpi_flows_root[]
to avoid redundant resets. The stats structure is shared per thread and
should only be reset once after all roots are cleared.
Refactored stats allocation and reset logic to avoid segmentation faults
when running ndpiReader in live_capture mode with the -m (duration) option.
- Introduced ndpi_stats_init(), ndpi_stats_reset(), and ndpi_stats_free()
to encapsulate lifecycle management of stats.
- Applied these functions in ndpiReader.c and reader_util.{c,h}.
- Prevented multiple allocations and ensured safe reuse of cumulative_stats
and per-thread stats structures between capture iterations.
Fixes: https://github.com/ntop/nDPI/issues/2903
Change the API to enable/disable protocols: you can set that via the
standard `ndpi_set_config()` function, as every configuration
parameters. By default, all protocols are enabled.
Split the (local) context initialization into two phases:
* `ndpi_init_detection_module()`: generic part. It does not depend on the
configuration and on the protocols being enabled or not. It also
calculates the real number of internal protocols
* `ndpi_finalize_initialization()`: apply the configuration. All the
initialization stuff that depend on protocols being enabled or not
must be put here
This is the last step to have the protocols number fully calculated at
runtime
Remove a (now) useless fuzzer.
Important API changes:
* remove `NDPI_LAST_IMPLEMENTED_PROTOCOL` define
* remove `ndpi_get_num_internal_protocols()`. To get the number of
configured protocols (internal and custom) you must use
`ndpi_get_num_protocols()` after having called `ndpi_finalize_initialization()`
The main difference is that the memory is allocated at runtime
Typical usercase:
```
struct ndpi_bitmask b;
ndpi_bitmask_alloc(&b, ndpi_get_num_internal_protocols());
ndpi_bitmask_set(&b, $BIT);
ndpi_bitmask_is_set(&b, $BIT);
[...]
ndpi_bitmask_dealloc(&b);
```
See #2136
We want to get rid of the defines `NDPI_MAX_SUPPORTED_PROTOCOLS` and
`NDPI_MAX_NUM_CUSTOM_PROTOCOLS`.
You can use:
```
ndpi_get_num_protocols()
```
See #2136
Removed some unused functions from public API
The main goal is not to have the bitmask depending on the total number
of protocols anymore: `NDPI_INTERNAL_PROTOCOL_BITMASK` depends only on
internal protocols, i.e. on `NDPI_MAX_INTERNAL_PROTOCOLS`, i.e.
custom-defined protocols are not counted.
See #2136
Keep the old data structure `NDPI_PROTOCOL_BITMASK` with the old
semantic.
Since we need to change the API (and all the application code...)
anyway, simplify the API: by default all the protocols are enabled.
If you need otherwise, please use `ndpi_init_detection_module_ext()`
instead of `ndpi_init_detection_module()` (you can find an example in
the `ndpiReader` code).
To update the application code you likely only need to remove these 3
lines from your code:
```
- NDPI_PROTOCOL_BITMASK all;
- NDPI_BITMASK_SET_ALL(all);
- ndpi_set_protocol_detection_bitmask2(ndpi_str, &all);
```
Removed an unused field and struct definition.
