Allow to customize:
- EventsWorkers: number of goroutines to handle kernel events.
Default 8.
- QueueEventsSize: max number of events in the queue.
By default 0, meaning that it'll relay on the available goroutines to
process the events. If it's > 0, and the daemon can't process the
events fast enough, they'll be queued. Once the queue is full, it'll
behave as it was of size 0.
If there're lost events, a message will be logged: "Lost ebpf events..."
- Added new configuration field to allow configure fw interception
number queue (default to 0):
"FwOptions": {
"QueueNum": 0
}
(we still need to reconfigure nfqueue queues in order for this to
take effect).
- If the fw configuration path is not supplied, default to
/etc/opensnitchd/system-fw.json
- The loggers were not being properly initialized.
- The fw was only being load on reload, instead of on startup
and reload.
Kudos to @1fishe2fishe for reporting this problem and proposing a
fix in #1130!
By default when adding the interception rules, we were killing all
existing connections, to force them go to the netfilter queue.
However in some environments this is not acceptable, so now it's configurable.
Besides, we were doing this only for nftables, so now it also works for
iptables.
When disabling the interception from the server (GUI), the network
interception was stopped, but the procs monitor kept running.
Now the procs monitor in use is also stopped, not to interfere with
the rest of the system (except 'proc').
improvements to the loggers modules:
- allow to specify a connection timeout (there was only a write
timeout).
- performance improvements when building the messages to be
written/sent.
- allow to restart the connection with remote servers if we fill up the
messages queue.
This can occur for example if we connect to a remote server, start
sending messages, but we haven't allowed other connections yet.
In this case the connections never recovered from this state, and we
weren't prompted to allow the needed connections.
(more work nd testing needed)
continuation of previous commit bde5d34deb
- Allow to reconfigure stats limits (how many events we keep on the
daemon, number of workers, ...)
- Allow to reconfigure loggers.
We only offered two options for the DefaultAction option: allow/deny.
Since a long time ago we support "reject"ing connections, but it was not
configurable as the DefaultAction.
Closes: #1108
We build the parent process tree of a process when it's executed
for the first time.
Now we also build the tree when an already running process opens a new
outbound connection by the first time.
if an invalid opensnitch-procs.o module was loaded, we were flooding
the log with errors.
In these cases stop processing events after 20 errors (random, we should
have no errors).
This may occur if the module is malformed (valid .o ebpf module but
different structs, etc), or when loading modules from other versions.
Closes: #1099#1082
We were sending to userspace unnecessary exit events, consuming
unnecessary CPU cycles.
We only intercept execve and execveat, but sched_process_exit is invoked
by more functions (sched_process_exit, clone, ...), so we were receiving
on the daemon events that we did nothing with them, apart from consuming
CPU cycles.
On some scenarios like on servers running saltstack (as salt-master),
this caused to consume more CPU than needed.
cherry picked from 15fcf67535
If the pop-ups' target is to filter by cmdline, but the typed/launched
command is not absolute or it starts with /proc, also filter by the
absolute path to the binary.
We were not handling configuration upgrades properly on rpm based
systems.
Now local changes to default-config.json and system-fw.json are kept,
and if the distributed files changes in the future, new files will be
created with the extension .rpmnew
We were not reacting to common exit signals, only to kill/interrupt
signals, so the DNS uprobes were never properly removed. Each uprobe
has the PID of the daemon in the identifier, so in theory, there
shouldn't be conflicts, but better clean our probes on exit.
previous to this commit with the daemon running
(and lot of starts/stops):
~ # cat /sys/kernel/debug/tracing/uprobe_events |wc -l
367
after stopping the daemon:
~ # cat /sys/kernel/debug/tracing/uprobe_events |wc -l
364
~ # > /sys/kernel/debug/tracing/uprobe_events
~ # cat /sys/kernel/debug/tracing/uprobe_events |wc -l
0
~ # cp opensnitchd-new /usr/bin/opensnitchd ; service opensnitchd start
~ # cat /sys/kernel/debug/tracing/uprobe_events |wc -l
3
~ # service opensnitchd stop
~ # cat /sys/kernel/debug/tracing/uprobe_events |wc -l
0
On 68c2c8ae1a we excluded failed execve*
calls from being delivered to userspace, in order to get the binary that
was executed and avoid errors/confusion.
But on aarch64, it seems that we fail to save the exec event to a map,
so the event is never delivered to userspace.
So for the time being, send the exec events as soon as they arrive on
aarch64, without checking if the call failed.
On the previus commit we just disabled dns uprobes for armhf/i386 to
avoid loading errors. A better fix is to initialized the structs used.
On armhf still fails after loading it, when attaching to the uprobes
(offsets?), and on i386 it doesn't seem to send anything to userspace
(more analysis needed).
- Increased the number of IPs associated with a domain that are
delivered to userspace. (getfedora.org returns 30 ipv4+ipv6).
- Fixed getting the aliases of a domain when using gethostbyname().
Added the path to the libc as well as the calculated offset for the
uprobe.
Don't return on the first error found loading a uprobe, instead try all
the uprobes and return if the loaded uprobes are 0.
The opensnitch-dns module was not loading on i386/arm architectures.
With the following changes it loads and some uprobes are attached.
for-loops unrolling doesn't still work though on i386/armhf (help
needed).
And on armhf the perf_output channel fails to load for some uprobes.
If the path of a process starts with /tmp/.mount_*, which is the common
path for appimages, use it as the default target on the popups.
Previously it was only added to the list of targets, but preselecting it
will help users to create rules for appimages.
There's a long running task that monitors established connections every
~2s.
When a connection is not found via ebpf or proc, sometimes it's found
there so we can use the inode to search for the process.
However on some systems the netlink call to dump the sockets may fail
continuously, wasting resources. It'll also fail if you block connections
to port 0 (common case for ICMP packets).
So if there're too many errors dumpng the sockets, stop this task for
these cases.
- When discovering the hierarchy of a process, reuse components of
the tree if they're already on cache, to improve speed and reduce
mem allocs.
- When building the tree of a proces, rebuild the tree if the first
component doesn't have pid 1. Otherwise reuse the tree.
Simplify the cache of connections by storing only the PID of a process,
instead of the Process object.
We can obtain the Process object from the cache of processes by PID.
Added config option to set how often the garbage collector runs.
For example:
"Internal": {
"GCPercent": 75
},
If this option is not specified in the config file, or the value
is 0, then the GC percentage is not configured.
More info:
https://pkg.go.dev/runtime/debug#SetGCPercent
