-
Notifications
You must be signed in to change notification settings - Fork 903
/
falco.yaml
1326 lines (1258 loc) · 55.9 KB
/
falco.yaml
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
# SPDX-License-Identifier: Apache-2.0
#
# Copyright (C) 2023 The Falco Authors.
#
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
################
# Config index #
################
# Here is an index of the configuration categories to help you navigate
# the Falco configuration file:
#
# (Falco command-line arguments)
# (Falco environment variables)
# Falco config files settings
# config_files [Stable]
# watch_config_files [Stable]
# Falco rules files
# rules_files [Stable]
# Falco rules
# rules [Incubating]
# Falco engine
# engine [Stable]
# Falco plugins
# load_plugins [Stable]
# plugins [Stable]
# Falco outputs settings
# time_format_iso_8601 [Stable]
# priority [Stable]
# json_output [Stable]
# json_include_output_property [Stable]
# json_include_tags_property [Stable]
# buffered_outputs [Stable]
# rule_matching [Incubating]
# outputs_queue [Stable]
# Falco outputs channels
# stdout_output [Stable]
# syslog_output [Stable]
# file_output [Stable]
# http_output [Stable]
# program_output [Stable]
# grpc_output [Stable]
# Falco exposed services
# grpc [Stable]
# webserver [Stable]
# Falco logging / alerting / metrics related to software functioning (basic)
# log_stderr [Stable]
# log_syslog [Stable]
# log_level [Stable]
# libs_logger [Stable]
# Falco logging / alerting / metrics related to software functioning (advanced)
# output_timeout [Stable]
# syscall_event_timeouts [Stable]
# syscall_event_drops [Stable] -> [CHANGE NOTICE] Automatic notifications will be simplified in Falco 0.38! If you depend on the detailed drop counters payload, use 'metrics.output_rule' along with 'metrics.kernel_event_counters_enabled' instead
# metrics [Stable]
# Falco performance tuning (advanced)
# base_syscalls [Stable]
# Falco libs
# falco_libs [Incubating]
########################
# Config maturity tags #
########################
# As per features adoption and deprecation proposal we support 4 levels of configuration keys maturity:
# * Sandbox -> Experimental/alpha features, not recommended for production use, can be removed at any time without further notice.
# * Incubating -> Beta features, long-term support is not guaranteed.
# * Stable -> General Availability (GA) features for which long-term support is expected.
# * Deprecated -> Deprecated keys, soon to be removed.
#
# For more info, please take a look at the proposal: https://github.com/falcosecurity/falco/blob/master/proposals/20231220-features-adoption-and-deprecation.md.
################################
# Falco command-line arguments #
################################
# To explore the latest command-line arguments supported by Falco for additional
# configuration, you can run `falco --help` in your terminal. You can also pass
# configuration options from this config file as command-line arguments by using
# the `-o` flag followed by the option name and value. In the following example,
# three config options (`json_output`, `log_level`, and
# `engine.kind`) are passed as command-line
# arguments with their corresponding values: falco -o "json_output=true"
# -o "log_level=debug" -o "engine.kind=kmod"
# Please note that command-line arguments take precedence over the options
# specified in this config file.
###############################
# Falco environment variables #
###############################
# Customize Falco settings using environment variables:
#
# - HOST_ROOT: Specifies the prefix to the underlying host `/proc` filesystem
# when deploying Falco over a container with read-only host mounts instead of
# directly on the host. Defaults to "/host".
#
# - FALCO_HOSTNAME: Customize the hostname output field logged by Falco by
# setting the "FALCO_HOSTNAME" environment variable.
#
# - FALCO_CGROUP_MEM_PATH: Specifies the file path holding the container
# memory usage metric for the `metrics` feature. Defaults to
# "/sys/fs/cgroup/memory/memory.usage_in_bytes" (Kubernetes).
#
# - SKIP_DRIVER_LOADER is used by the Falco fat image to skip the driver loading part.
#
# - FALCO_FRONTEND is useful when set to noninteractive to skip the dialog choice during
# the installation of Falco deb/rpm packages. This setting is somewhat similar to DEBIAN_FRONTEND.
#
# - FALCO_DRIVER_CHOICE is useful when set to kmod, ebpf, or modern_ebpf (matching the names
# used in engine.kind in the Falco config) during the installation of Falco deb/rpm packages.
# It skips the dialog choice but retains the driver configuration.
#
# - FALCOCTL_ENABLED is useful when set to 'no' during the installation of Falco deb/rpm packages,
# disabling the automatic artifacts followed by falcoctl.
###############################
# Falco config files settings #
###############################
# [Stable] `config_files`
#
# Falco will load additional configs files specified here.
# Their loading is assumed to be made *after* main config file has been processed,
# exactly in the order they are specified.
# Therefore, loaded config files *can* override values from main config file.
# Also, nested include is not allowed, ie: included config files won't be able to include other config files.
#
# Like for 'rules_files', specifying a folder will load all the configs files present in it in a lexicographical order.
config_files:
- /etc/falco/config.d
# [Stable] `watch_config_files`
#
# Falco monitors configuration and rules files for changes and automatically
# reloads itself to apply the updated configuration when any modifications are
# detected. This feature is particularly useful when you want to make real-time
# changes to the configuration or rules of Falco without interrupting its
# operation or losing its state. For more information about Falco's state
# engine, please refer to the `base_syscalls` section.
watch_config_files: true
#####################
# Falco rules files #
#####################
# [Stable] `rules_files`
# NOTICE: Before Falco 0.38, this config key was `rules_file` (singular form), which is now deprecated in favor of `rules_files` (plural form).
#
# Falco rules can be specified using files or directories, which are loaded at
# startup.
#
# If the entry is a file, it will be read directly. If the entry is a directory,
# all files within that directory will be read in alphabetical order.
#
# The falco_rules.yaml file ships with the Falco package and is overridden with
# every new software version. falco_rules.local.yaml is only created if it
# doesn't already exist.
#
# To customize the set of rules, you can add your modifications to any file.
# It's important to note that the files or directories are read in the order
# specified here. In addition, rules are loaded by Falco in the order they
# appear within each rule file.
#
# If you have any customizations intended to override a previous configuration,
# make sure they appear in later files to take precedence. On the other hand, if
# the conditions of rules with the same event type(s) have the potential to
# overshadow each other, ensure that the more important rule appears first. This
# is because rules are evaluated on a "first match wins" basis, where the first
# rule that matches the conditions will be applied, and subsequent rules will
# not be evaluated for the same event type.
#
# By arranging the order of files and rules thoughtfully, you can ensure that
# desired customizations and rule behaviors are prioritized and applied as
# intended.
#
# With Falco 0.36 and beyond, it's now possible to apply multiple rules that match
# the same event type, eliminating concerns about rule prioritization based on the
# "first match wins" principle. However, enabling the `all` matching option may result
# in a performance penalty. We recommend carefully testing this alternative setting
# before deploying it in production. Read more under the `rule_matching` configuration.
rules_files:
- /etc/falco/falco_rules.yaml
- /etc/falco/falco_rules.local.yaml
- /etc/falco/rules.d
# [Incubating] `rules`
#
# --- [Description]
#
# Falco rules can be enabled or disabled by name (with wildcards *) and/or by tag.
#
# This configuration is applied after all rules files have been loaded, including
# their overrides, and will take precedence over the enabled/disabled configuration
# specified or overridden in the rules files.
#
# The ordering matters and selections are evaluated in order. For instance, if you
# need to only enable a rule you would first disable all of them and then only
# enable what you need, regardless of the enabled status in the files.
#
# --- [Examples]
#
# Only enable two rules:
#
# rules:
# - disable:
# rule: "*"
# - enable:
# rule: Netcat Remote Code Execution in Container
# - enable:
# rule: Delete or rename shell history
#
# Disable all rules with a specific tag:
#
# rules:
# - disable:
# tag: network
#
################
# Falco engine #
################
# [Stable] `engine`
#
# --- [Description]
#
# Falco supports different engines to generate events.
# Choose the appropriate engine kind based on your system's configuration and requirements.
#
# Available engines:
# - `kmod`: Kernel Module (Kernel Module)
# - `ebpf`: eBPF (eBPF probe)
# - `modern_ebpf`: Modern eBPF (CO-RE eBPF probe)
# - `gvisor`: gVisor (gVisor sandbox)
# - `replay`: Replay a scap trace file
# - `nodriver`: No driver is injected into the system.
# This is useful to debug and to run plugins with 'syscall' source.
#
# Only one engine can be specified in the `kind` key.
# Moreover, for each engine multiple options might be available,
# grouped under engine-specific configuration keys.
# Some of them deserve an in-depth description:
#
################### `buf_size_preset`
#
# --- [Description]
#
# The syscall buffer index determines the size of the shared space between Falco
# and its drivers. This shared space serves as a temporary storage for syscall
# events, allowing them to be transferred from the kernel to the userspace
# efficiently. The buffer size for each online CPU is determined by the buffer
# index, and each CPU has its own dedicated buffer. Adjusting this index allows
# you to control the overall size of the syscall buffers.
#
# --- [Usage]
#
# The index 0 is reserved, and each subsequent index corresponds to an
# increasing size in bytes. For example, index 1 corresponds to a size of 1 MB,
# index 2 corresponds to 2 MB, and so on:
#
# [(*), 1 MB, 2 MB, 4 MB, 8 MB, 16 MB, 32 MB, 64 MB, 128 MB, 256 MB, 512 MB]
# ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^
# | | | | | | | | | | |
# 0 1 2 3 4 5 6 7 8 9 10
#
#
# The buffer dimensions in bytes are determined by the following requirements:
# (1) a power of 2.
# (2) a multiple of your system_page_dimension.
# (3) greater than `2 * (system_page_dimension).
#
# The buffer size constraints may limit the usability of certain indexes. Let's
# consider an example to illustrate this:
#
# If your system has a page size of 1 MB, the first available buffer size would
# be 4 MB because 2 MB is exactly equal to 2 * (system_page_size), which is not
# sufficient as we require more than 2 * (system_page_size). In this example, it
# is evident that if the page size is 1 MB, the first index that can be used is 3.
#
# However, in most cases, these constraints do not pose a limitation, and all
# indexes from 1 to 10 can be used. You can check your system's page size using
# the Falco `--page-size` command-line option.
#
# --- [Suggestions]
#
# The buffer size was previously fixed at 8 MB (index 4). You now have the
# option to adjust the size based on your needs. Increasing the size, such as to
# 16 MB (index 5), can reduce syscall drops in heavy production systems, but may
# impact performance. Decreasing the size can speed up the system but may
# increase syscall drops. It's important to note that the buffer size is mapped
# twice in the process' virtual memory, so a buffer of 8 MB will result in a 16
# MB area in virtual memory. Use this parameter with caution and only modify it
# if the default size is not suitable for your use case.
#
################### `drop_failed_exit`
#
# --- [Description]
#
# Enabling this option in Falco allows it to drop failed system call exit events
# in the kernel drivers before pushing them onto the ring buffer. This
# optimization can result in lower CPU usage and more efficient utilization of
# the ring buffer, potentially reducing the number of event losses. However, it
# is important to note that enabling this option also means sacrificing some
# visibility into the system.
#
################### `cpus_for_each_buffer` (modern_ebpf only)
#
# --- [Description]
#
# The modern_bpf driver in Falco utilizes the new BPF ring buffer, which has a
# different memory footprint compared to the current BPF driver that uses the
# perf buffer. The Falco core maintainers have discussed the differences and
# their implications, particularly in Kubernetes environments where limits need
# to be carefully set to avoid interference with the Falco daemonset deployment
# from the OOM killer. Based on guidance received from the kernel mailing list,
# it is recommended to assign multiple CPUs to one buffer instead of allocating
# a buffer for each CPU individually. This helps optimize resource allocation
# and prevent potential issues related to memory usage.
#
# This is an index that controls how many CPUs you want to assign to a single
# syscall buffer (ring buffer). By default, for modern_bpf every syscall buffer
# is associated to 2 CPUs, so the mapping is 1:2. The modern BPF probe allows
# you to choose different mappings, for example, changing the value to `1`
# results in a 1:1 mapping and would mean one syscall buffer for each CPU (this
# is the default for the `bpf` driver).
#
# --- [Usage]
#
# You can choose an index from 0 to MAX_NUMBER_ONLINE_CPUs to set the dimension
# of the syscall buffers. The value 0 represents a single buffer shared among
# all online CPUs. It serves as a flexible option when the exact number of
# online CPUs is unknown. Here's an example to illustrate this:
#
# Consider a system with 7 online CPUs:
#
# CPUs 0 X 2 3 X X 6 7 8 9 (X means offline CPU)
#
# - `1` means a syscall buffer for each CPU so 7 buffers
#
# CPUs 0 X 2 3 X X 6 7 8 9 (X means offline CPU)
# | | | | | | |
# BUFFERs 0 1 2 3 4 5 6
#
# - `2` (Default value) means a syscall buffer for each CPU pair, so 4 buffers
#
# CPUs 0 X 2 3 X X 6 7 8 9 (X means offline CPU)
# | | | | | | |
# BUFFERs 0 0 1 1 2 2 3
#
# Please note that in this example, there are 4 buffers in total. Three of the
# buffers are associated with pairs of CPUs, while the last buffer is mapped to
# a single CPU. This arrangement is necessary because we have an odd number of
# CPUs.
#
# - `0` or `MAX_NUMBER_ONLINE_CPUs` mean a syscall buffer shared between all
# CPUs, so 1 buffer
#
# CPUs 0 X 2 3 X X 6 7 8 9 (X means offline CPU)
# | | | | | | |
# BUFFERs 0 0 0 0 0 0 0
#
# Moreover, you have the option to combine this parameter with
# `buf_size_preset` index. For instance, you can create a large shared
# syscall buffer of 512 MB (using buf_size_preset=10) that is
# allocated among all the online CPUs.
#
# --- [Suggestions]
#
# The default choice of index 2 (one syscall buffer for each CPU pair) was made
# because the modern bpf probe utilizes a different memory allocation strategy
# compared to the other two drivers (bpf and kernel module). However, you have
# the flexibility to experiment and find the optimal configuration for your
# system.
#
# When considering a fixed buf_size_preset and a fixed buffer dimension:
# - Increasing this configs value results in lower number of buffers and you can
# speed up your system and reduce memory usage
# - However, using too few buffers may increase contention in the kernel,
# leading to a slowdown.
#
# If you have low event throughputs and minimal drops, reducing the number of
# buffers (higher `cpus_for_each_buffer`) can lower the memory footprint.
#
engine:
kind: modern_ebpf
kmod:
buf_size_preset: 4
drop_failed_exit: false
ebpf:
# path to the elf file to load.
probe: ${HOME}/.falco/falco-bpf.o
buf_size_preset: 4
drop_failed_exit: false
modern_ebpf:
cpus_for_each_buffer: 2
buf_size_preset: 4
drop_failed_exit: false
replay:
# path to the capture file to replay (eg: /path/to/file.scap)
capture_file: ""
gvisor:
# A Falco-compatible configuration file can be generated with
# '--gvisor-generate-config' and utilized for both runsc and Falco.
config: ""
# Set gVisor root directory for storage of container state when used
# in conjunction with 'gvisor.config'. The 'gvisor.root' to be passed
# is the one usually passed to 'runsc --root' flag.
root: ""
#################
# Falco plugins #
#################
# [Stable] `load_plugins` and `plugins`
#
# --- [Description]
#
# Falco plugins enable integration with other services in your ecosystem.
# They allow Falco to extend its functionality and leverage data sources such as
# Kubernetes audit logs or AWS CloudTrail logs. This enables Falco to perform
# fast on-host detections beyond syscalls and container events. The plugin
# system will continue to evolve with more specialized functionality in future
# releases.
#
# Please refer to the plugins repo at
# https://github.com/falcosecurity/plugins/blob/master/plugins/ for detailed
# documentation on the available plugins. This repository provides comprehensive
# information about each plugin and how to utilize them with Falco.
#
# Please note that if your intention is to enrich Falco syscall logs with fields
# such as `k8s.ns.name`, `k8s.pod.name`, and `k8s.pod.*`, you do not need to use
# the `k8saudit` plugin. This information is automatically extracted from
# the container runtime socket. The `k8saudit` plugin is specifically designed
# to integrate with Kubernetes audit logs and is not required for basic enrichment
# of syscall logs with Kubernetes-related fields.
#
# --- [Usage]
#
# Disabled by default, indicated by an empty `load_plugins` list. Each plugin meant
# to be enabled needs to be listed as explicit list item.
#
# For example, if you want to use the `k8saudit` plugin,
# ensure it is configured appropriately and then change this to:
# load_plugins: [k8saudit, json]
load_plugins: []
# Customize subsettings for each enabled plugin. These settings will only be
# applied when the corresponding plugin is enabled using the `load_plugins`
# option.
plugins:
- name: k8saudit
library_path: libk8saudit.so
init_config: ""
# maxEventSize: 262144
# webhookMaxBatchSize: 12582912
# sslCertificate: /etc/falco/falco.pem
open_params: "http://:9765/k8s-audit"
- name: cloudtrail
library_path: libcloudtrail.so
# see docs for init_config and open_params:
# https://github.com/falcosecurity/plugins/blob/master/plugins/cloudtrail/README.md
- name: json
library_path: libjson.so
##########################
# Falco outputs settings #
##########################
# [Stable] `time_format_iso_8601`
#
# When enabled, Falco will display log and output messages with times in the ISO
# 8601 format. By default, times are shown in the local time zone determined by
# the /etc/localtime configuration.
time_format_iso_8601: false
# [Incubating] `buffer_format_base64`
#
# When enabled, Falco will output data buffer with base64 encoding. This is useful
# for encoding binary data that needs to be used over media designed to consume
# this format.
buffer_format_base64: false
# [Stable] `priority`
#
# Any rule with a priority level more severe than or equal to the specified
# minimum level will be loaded and run by Falco. This allows you to filter and
# control the rules based on their severity, ensuring that only rules of a
# certain priority or higher are active and evaluated by Falco. Supported
# levels: "emergency", "alert", "critical", "error", "warning", "notice",
# "info", "debug"
priority: debug
# [Stable] `json_output`
#
# When enabled, Falco will output alert messages and rules file
# loading/validation results in JSON format, making it easier for downstream
# programs to process and consume the data. By default, this option is disabled.
json_output: false
# [Stable] `json_include_output_property`
#
# When using JSON output in Falco, you have the option to include the "output"
# property itself in the generated JSON output. The "output" property provides
# additional information about the purpose of the rule. To reduce the logging
# volume, it is recommended to turn it off if it's not necessary for your use
# case.
json_include_output_property: true
# [Incubating] `json_include_message_property`
#
# When using JSON output in Falco, you have the option to include the formatted
# rule output without timestamp or priority. For instance, if a rule specifies
# an "output" property like "Opened process %proc.name" the "message" field will
# only contain "Opened process bash" whereas the "output" field will contain more
# information.
json_include_message_property: false
# [Stable] `json_include_tags_property`
#
# When using JSON output in Falco, you have the option to include the "tags"
# field of the rules in the generated JSON output. The "tags" field provides
# additional metadata associated with the rule. To reduce the logging volume,
# if the tags associated with the rule are not needed for your use case or can
# be added at a later stage, it is recommended to turn it off.
json_include_tags_property: true
# [Stable] `buffered_outputs`
#
# Enabling buffering for the output queue can offer performance optimization,
# efficient resource usage, and smoother data flow, resulting in a more reliable
# output mechanism. By default, buffering is disabled (false).
buffered_outputs: false
# [Incubating] `rule_matching`
#
# The `rule_matching` configuration key's values are:
# - `first`: Falco stops checking conditions of rules against upcoming event
# at the first matching rule
# - `all`: Falco will continue checking conditions of rules even if a matching
# one was already found
#
# Rules conditions are evaluated in the order they are defined in the rules files.
# For this reason, when using `first` as value, only the first defined rule will
# trigger, possibly shadowing other rules.
# In case `all` is used as value, rules still trigger in the order they were
# defined.
#
# Effectively, with this setting, it is now possible to apply multiple rules that match
# the same event type. This eliminates concerns about rule prioritization based on the
# "first match wins" principle. However, enabling the `all` matching option may result in
# a performance penalty. We recommend carefully testing this alternative setting before
# deploying it in production.
rule_matching: first
# [Stable] `outputs_queue`
#
# Falco utilizes tbb::concurrent_bounded_queue for handling outputs, and this parameter
# allows you to customize the queue capacity. Please refer to the official documentation:
# https://uxlfoundation.github.io/oneTBB/main/tbb_userguide/Concurrent_Queue_Classes.html.
# On a healthy system with optimized Falco rules, the queue should not fill up.
# If it does, it is most likely happening due to the entire event flow being too slow,
# indicating that the server is under heavy load.
#
# `capacity`: the maximum number of items allowed in the queue is determined by this value.
# Setting the value to 0 (which is the default) is equivalent to keeping the queue unbounded.
# In other words, when this configuration is set to 0, the number of allowed items is
# effectively set to the largest possible long value, disabling this setting.
#
# In the case of an unbounded queue, if the available memory on the system is consumed,
# the Falco process would be OOM killed. When using this option and setting the capacity,
# the current event would be dropped, and the event loop would continue. This behavior mirrors
# kernel-side event drops when the buffer between kernel space and user space is full.
outputs_queue:
capacity: 0
# [Sandbox] `append_output`
#
# Add information to the Falco output.
# With this setting you can add more information to the Falco output message, customizable by
# rule, tag or source.
# You can also add additional data that will appear in the output_fields property
# of JSON formatted messages or gRPC output but will not be part of the regular output message.
# This allows you to add custom fields that can help you filter your Falco events without
# polluting the message text.
#
# Each append_output entry has an optional `match` map which specifies which rules will be
# affected.
# `match`:
# `rule`: append output only to a specific rule
# `source`: append output only to a specific source
# `tags`: append output only to rules that have all of the specified tags
# If none of the above are specified (or `match` is omitted)
# output is appended to all events.
# If more than one match condition is specified output will be appended to events
# that match all conditions.
# And several options to add output:
# `extra_output`: add output to the Falco message
# `extra_fields`: add new fields to the JSON output and structured output, which will not
# affect the regular Falco message in any way. These can be specified as a
# custom name with a custom format or as any supported field
# (see: https://falco.org/docs/reference/rules/supported-fields/)
#
# Example:
#
# append_output:
# - match:
# source: syscall
# extra_output: "on CPU %evt.cpu"
# extra_fields:
# - home_directory: "${HOME}"
# - evt.hostname
#
# In the example above every event coming from the syscall source will get an extra message
# at the end telling the CPU number. In addition, if `json_output` is true, in the "output_fields"
# property you will find three new ones: "evt.cpu", "home_directory" which will contain the value of the
# environment variable $HOME, and "evt.hostname" which will contain the hostname.
##########################
# Falco outputs channels #
##########################
# Falco supports various output channels, such as syslog, stdout, file, gRPC,
# webhook, and more. You can enable or disable these channels as needed to
# control where Falco alerts and log messages are directed. This flexibility
# allows seamless integration with your preferred logging and alerting systems.
# Multiple outputs can be enabled simultaneously.
# [Stable] `stdout_output`
#
# Redirect logs to standard output.
stdout_output:
enabled: true
# [Stable] `syslog_output`
#
# Send logs to syslog.
syslog_output:
enabled: true
# [Stable] `file_output`
#
# When appending Falco alerts to a file, each new alert will be added to a new
# line. It's important to note that Falco does not perform log rotation for this
# file. If the `keep_alive` option is set to `true`, the file will be opened once
# and continuously written to, else the file will be reopened for each output
# message. Furthermore, the file will be closed and reopened if Falco receives
# the SIGUSR1 signal.
file_output:
enabled: false
keep_alive: false
filename: ./events.txt
# [Stable] `http_output`
#
# Send logs to an HTTP endpoint or webhook.
#
# When using falcosidekick, it is necessary to set `json_output` to true, which is
# conveniently done automatically for you when using `falcosidekick.enabled=true`.
http_output:
enabled: false
url: http://some.url
user_agent: "falcosecurity/falco"
# Tell Falco to not verify the remote server.
insecure: false
# Path to the CA certificate that can verify the remote server.
ca_cert: ""
# Path to a specific file that will be used as the CA certificate store.
ca_bundle: ""
# Path to a folder that will be used as the CA certificate store. CA certificate need to be
# stored as indivitual PEM files in this directory.
ca_path: "/etc/ssl/certs"
# Tell Falco to use mTLS
mtls: false
# Path to the client cert.
client_cert: "/etc/ssl/certs/client.crt"
# Path to the client key.
client_key: "/etc/ssl/certs/client.key"
# Whether to echo server answers to stdout
echo: false
compress_uploads: false
keep_alive: false
# [Stable] `program_output`
#
# Redirect the output to another program or command.
#
# Possible additional things you might want to do with program output:
# - send to a slack webhook:
# program: "jq '{text: .output}' | curl -d @- -X POST https://hooks.slack.com/services/XXX"
# - logging (alternate method than syslog):
# program: logger -t falco-test
# - send over a network connection:
# program: nc host.example.com 80
# If `keep_alive` is set to `true`, the program will be started once and
# continuously written to, with each output message on its own line. If
# `keep_alive` is set to `false`, the program will be re-spawned for each output
# message. Furthermore, the program will be re-spawned if Falco receives
# the SIGUSR1 signal.
program_output:
enabled: false
keep_alive: false
program: "jq '{text: .output}' | curl -d @- -X POST https://hooks.slack.com/services/XXX"
# [Stable] `grpc_output`
#
# Use gRPC as an output service.
#
# gRPC is a modern and high-performance framework for remote procedure calls
# (RPC). It utilizes protocol buffers for efficient data serialization. The gRPC
# output in Falco provides a modern and efficient way to integrate with other
# systems. By default the setting is turned off. Enabling this option stores
# output events in memory until they are consumed by a gRPC client. Ensure that
# you have a consumer for the output events or leave it disabled.
grpc_output:
enabled: false
##########################
# Falco exposed services #
##########################
# [Stable] `grpc`
#
# Falco provides support for running a gRPC server using two main binding types:
# 1. Over the network with mandatory mutual TLS authentication (mTLS), which
# ensures secure communication
# 2. Local Unix socket binding with no authentication. By default, the
# gRPCserver in Falco is turned off with no enabled services (see
# `grpc_output`setting).
#
# To configure the gRPC server in Falco, you can make the following changes to
# the options:
#
# - Uncomment the relevant configuration options related to the gRPC server.
# - Update the paths of the generated certificates for mutual TLS authentication
# if you choose to use mTLS.
# - Specify the address to bind and expose the gRPC server.
# - Adjust the threadiness configuration to control the number of threads and
# contexts used by the server.
#
# Keep in mind that if any issues arise while creating the gRPC server, the
# information will be logged, but it will not stop the main Falco daemon.
# gRPC server using mTLS
# grpc:
# enabled: true
# bind_address: "0.0.0.0:5060"
# # When the `threadiness` value is set to 0, Falco will automatically determine
# # the appropriate number of threads based on the number of online cores in the system.
# threadiness: 0
# private_key: "/etc/falco/certs/server.key"
# cert_chain: "/etc/falco/certs/server.crt"
# root_certs: "/etc/falco/certs/ca.crt"
# gRPC server using a local unix socket
grpc:
enabled: false
bind_address: "unix:///run/falco/falco.sock"
# When the `threadiness` value is set to 0, Falco will automatically determine
# the appropriate number of threads based on the number of online cores in the system.
threadiness: 0
# [Stable] `webserver`
#
# Falco supports an embedded webserver that runs within the Falco process,
# providing a lightweight and efficient way to expose web-based functionalities
# without the need for an external web server. The following endpoints are
# exposed:
# - /healthz: designed to be used for checking the health and availability of
# the Falco application (the name of the endpoint is configurable).
# - /versions: responds with a JSON object containing the version numbers of the
# internal Falco components (similar output as `falco --version -o
# json_output=true`).
#
# Please note that the /versions endpoint is particularly useful for other Falco
# services, such as `falcoctl`, to retrieve information about a running Falco
# instance. If you plan to use `falcoctl` locally or with Kubernetes, make sure
# the Falco webserver is enabled.
#
# The behavior of the webserver can be controlled with the following options,
# which are enabled by default:
#
# The `ssl_certificate` option specifies a combined SSL certificate and
# corresponding key that are contained in a single file. You can generate a
# key/cert as follows:
#
# $ openssl req -newkey rsa:2048 -nodes -keyout key.pem -x509 -days 365 -out
# certificate.pem $ cat certificate.pem key.pem > falco.pem $ sudo cp falco.pem
# /etc/falco/falco.pem
webserver:
enabled: true
# When the `threadiness` value is set to 0, Falco will automatically determine
# the appropriate number of threads based on the number of online cores in the system.
threadiness: 0
listen_port: 8765
# Can be an IPV4 or IPV6 address, defaults to IPV4
listen_address: 0.0.0.0
k8s_healthz_endpoint: /healthz
# [Incubating] `prometheus_metrics_enabled`
#
# Enable the metrics endpoint providing Prometheus values
# It will only have an effect if metrics.enabled is set to true as well.
prometheus_metrics_enabled: false
ssl_enabled: false
ssl_certificate: /etc/falco/falco.pem
##############################################################################
# Falco logging / alerting / metrics related to software functioning (basic) #
##############################################################################
# [Stable] `log_stderr` and `log_syslog`
#
# Falco's logs related to the functioning of the software, which are not related
# to Falco alert outputs but rather its lifecycle, settings and potential
# errors, can be directed to stderr and/or syslog.
log_stderr: true
log_syslog: true
# [Stable] `log_level`
#
# The `log_level` setting determines the minimum log level to include in Falco's
# logs related to the functioning of the software. This setting is separate from
# the `priority` field of rules and specifically controls the log level of
# Falco's operational logging. By specifying a log level, you can control the
# verbosity of Falco's operational logs. Only logs of a certain severity level
# or higher will be emitted. Supported levels: "emergency", "alert", "critical",
# "error", "warning", "notice", "info", "debug".
log_level: info
# [Stable] `libs_logger`
#
# The `libs_logger` setting in Falco determines the minimum log level to include
# in the logs related to the functioning of the software of the underlying
# `libs` library, which Falco utilizes. This setting is independent of the
# `priority` field of rules and the `log_level` setting that controls Falco's
# operational logs. It allows you to specify the desired log level for the `libs`
# library specifically, providing more granular control over the logging
# behavior of the underlying components used by Falco. Only logs of a certain
# severity level or higher will be emitted. Supported levels: "fatal",
# "critical", "error", "warning", "notice", "info", "debug", "trace". It is not
# recommended for production use.
libs_logger:
enabled: false
severity: debug
#################################################################################
# Falco logging / alerting / metrics related to software functioning (advanced) #
#################################################################################
# [Stable] `output_timeout`
#
# Generates Falco operational logs when `log_level=notice` at minimum
#
# A timeout error occurs when a process or operation takes longer to complete
# than the allowed or expected time limit. In the context of Falco, an output
# timeout error refers to the situation where an output channel fails to deliver
# an alert within a specified deadline. Various reasons, such as network issues,
# resource constraints, or performance bottlenecks can cause timeouts.
#
# The `output_timeout` parameter specifies the duration, in milliseconds, to
# wait before considering the deadline exceeded. By default, the timeout is set
# to 2000ms (2 seconds), meaning that the consumer of Falco outputs can block
# the Falco output channel for up to 2 seconds without triggering a timeout
# error.
#
# Falco actively monitors the performance of output channels. With this setting
# the timeout error can be logged, but please note that this requires setting
# Falco's operational logs `log_level` to a minimum of `notice`.
#
# It's important to note that Falco outputs will not be discarded from the
# output queue. This means that if an output channel becomes blocked
# indefinitely, it indicates a potential issue that needs to be addressed by the
# user.
output_timeout: 2000
# [Stable] `syscall_event_timeouts`
#
# Generates Falco operational logs when `log_level=notice` at minimum
#
# Falco utilizes a shared buffer between the kernel and userspace to receive
# events, such as system call information, in userspace. However, there may be
# cases where timeouts occur in the underlying libraries due to issues in
# reading events or the need to skip a particular event. While it is uncommon
# for Falco to experience consecutive event timeouts, it has the capability to
# detect such situations. You can configure the maximum number of consecutive
# timeouts without an event after which Falco will generate an alert, but please
# note that this requires setting Falco's operational logs `log_level` to a
# minimum of `notice`. The default value is set to 1000 consecutive timeouts
# without receiving any events. The mapping of this value to a time interval
# depends on the CPU frequency.
syscall_event_timeouts:
max_consecutives: 1000
# [Stable] `syscall_event_drops` -> [CHANGE NOTICE] Automatic notifications will be simplified in Falco 0.38! If you depend on the detailed drop counters payload, use 'metrics.output_rule' along with 'metrics.kernel_event_counters_enabled' instead
#
# Generates "Falco internal: syscall event drop" rule output when `priority=debug` at minimum
#
# --- [Description]
#
# Falco uses a shared buffer between the kernel and userspace to pass system
# call information. When Falco detects that this buffer is full and system calls
# have been dropped, it can take one or more of the following actions:
# - ignore: do nothing (default when list of actions is empty)
# - log: log a DEBUG message noting that the buffer was full
# - alert: emit a Falco alert noting that the buffer was full
# - exit: exit Falco with a non-zero rc
#
# Notice it is not possible to ignore and log/alert messages at the same time.
#
# The rate at which log/alert messages are emitted is governed by a token
# bucket. The rate corresponds to one message every 30 seconds with a burst of
# one message (by default).
#
# The messages are emitted when the percentage of dropped system calls with
# respect the number of events in the last second is greater than the given
# threshold (a double in the range [0, 1]). If you want to be alerted on any
# drops, set the threshold to 0.
#
# For debugging/testing it is possible to simulate the drops using the
# `simulate_drops: true`. In this case the threshold does not apply.
#
# --- [Usage]
#
# Enabled by default, but requires Falco rules config `priority` set to `debug`.
# Emits a Falco rule named "Falco internal: syscall event drop" as many times in
# a given time period as dictated by the settings. Statistics here reflect the
# delta in a 1s time period.
#
# If instead you prefer periodic metrics of monotonic counters at a regular
# interval, which include syscall drop statistics and additional metrics,
# explore the `metrics` configuration option.
syscall_event_drops:
threshold: .1
actions:
- log
- alert
rate: .03333
max_burst: 1
simulate_drops: false
# [Stable] `metrics`
#
# Generates "Falco internal: metrics snapshot" rule output when `priority=info` at minimum
# By selecting `output_file`, equivalent JSON output will be appended to a file.
#
# periodic metric snapshots (including stats and resource utilization) captured
# at regular intervals
#
# --- [Warning]
#
# Due to a regression (https://github.com/falcosecurity/falco/issues/2821) some metrics
# like `falco.host_num_cpus` or `falco.start_ts` will not be available when you use
# source plugins (like k8saudit).
#
# --- [Description]
#
# Consider these key points about the `metrics` feature in Falco:
#
# - It introduces a redesigned stats/metrics system.
# - Native support for resource utilization metrics and specialized performance
# metrics.
# - Metrics are emitted as monotonic counters at predefined intervals
# (snapshots).
# - All metrics are consolidated into a single log message, adhering to the
# established rules schema and naming conventions.
# - Additional info fields complement the metrics and facilitate customized
# statistical analyses and correlations.
# - The metrics framework is designed for easy future extension.
#
# The `metrics` feature follows a specific schema and field naming convention.
# All metrics are collected as subfields under the `output_fields` key, similar
# to regular Falco rules. Each metric field name adheres to the grammar used in
# Falco rules. There are two new field classes introduced: `falco.` and `scap.`.
# The `falco.` class represents userspace counters, statistics, resource
# utilization, or useful information fields. The `scap.` class represents
# counters and statistics mostly obtained from Falco's kernel instrumentation
# before events are sent to userspace, but can include scap userspace stats as
# well.