MRTS is a utility that helps you create rule sets and their tests for ModSecurity or ModSecurity compliant engines (eg. Coraza) for regression testing. The format of the test cases is compatible with go-ftw.
Please note that this project is in very beta state.
The goals of this project:
- create as many rules as possible for ModSecurity to test its behavior
- create as many tests as possible for each rule
ModSecurity uses its rules targets, operators, transformations (special actions) and so many other components. It is necessary to test their behavior.
Note, that libmodsecurity3 has a regression test framework with several test cases, but it tests only the library, not the embedded state. For example we don't know anything about behavior of Nginx connector.
With the generated rules and tests we can check the operation of mod-security2 and Nginx-connector.
The generated rules can help in the quality assurance of these engines, e.g. after sending pull requests, we can verify that the change did not change the expected behavior.
The idea is to generate rules to see what happens to a particular component. It's not as trivial as it seems at first glance. Consider there are 5 phases - can we be sure of behaviors are same in each phases? Variables can be collections, every combinations of collections works as we need? Do you want to check the variable against multiple operator? With multiple operator arguments?
It's easy to see that the number of possible combinations can be infinite. It could be too much efford to write a rule for every possible format - and a test case too.
Instead of doing this, we can make a description about the object, and expand the possible combinations and their test cases.
Rules are generated based on templates. You can define as many templates as you want, and you can apply them for each rule description.
The operation is very simple: create one or more configuration files, and run the generator script with those files. the format of the files is some structured data (YAML, JSON) which can be human readable (and writable). Generator will produce rules with combination of given:
- target + colkeys (collection keys) (eg.
ARGS:arg1
,ARGS:arg2
,ARGS:arg1|ARGS:arg2
) - operators (you can pass multiple operators)
- operator arguments - also can pass several arguments
- phases - it depends on your choose, in which phases you want to check the target
The framework has an API that describes which keywords can be used for the description. To avoid unwanted typing, there are several global settings that are derived in each case.
The syntax of API can be YAML or JSON.
Every global settings should be put under the global
keyword, eg:
global:
version: MRTS/0.1
baseid: 100000
You can place global
keywords in every file, each subsequent occurrence will overwrite the previous one. The files are processed in ABC order, later overwriting does not change the previous settings.
This keyword shows that the next block contains global settings.
version
shows the current version of framework and can appear as constant in templates (see later).
baseid
defines the first id
what a rule can use. Inside the generator increments that for every rule, and that variable is avaluable as $CURRID
(see later).
This global variable defines the default operator for rules. You can overwrite it at every case, moreover you can add more operators for every case. But if you don't want to type, the operator
member can be omitted.
Syntax:
global:
default_operator: "@rx"
templates
defines a list of templates. Each item in the list is a template
block - see template section.
This keyword describes an object. Each keys of the object is a phase value, and the value is the method what you prefer to send the request during the test (with go-ftw
). In phase:1
we prefer to use GET
method, in case of each other the POST
. Example:
global:
default_tests_phase_methods
- 1: get
- 2: post
- 3: post
- 4: post
- 5: post
You can create one or more template which can be used for generated rules. A template object has two other named objects: name
and template
.
name
must be a unique name, and template
is a text with the rule definition. This definition can contain macros - see macros section.
An example for templates
:
- name: "SecRule for TARGETS"
template: |
SecRule ${TARGET}$ "${OPERATOR}$ ${OPARG}$" \
"id:${CURRID}$,\
phase:${PHASE}$,\
deny,\
t:none,\
log,\
msg:'%{MATCHED_VAR_NAME} was caught in phase:${PHASE}$',\
ver:'${VERSION}$'"
As you can see the template macros are delimited by ${...}$
.
Marcos are coming from the definition. That can be from the unique definition or if there no such variable, then from the globals.
Avaliable macros:
${TARGET}$
the variable name when you want to check the SecRule's variable${OPERATOR}$
is the used operator; it must be placed with the leading@
, eg.@rx
.${OPARG}$
is the argument of the operator in the rule${CURRID}$
is the incrementedid
, which guaranties that every generated rule will have a uniqueid
${PHASE}$
is the current phase in the list that you define in the definition file (see later its syntax)${VERSION}$
is theVERSION
, see above${ACTIONS}$
is the actions you want in the rule${DIRECTIVES}$
is the additional directives you want next to the rule
Please note that %{MATCHED_VAR_NAME}
is not a tool macro, but the ModSecurity's macro. You can use them where you want.
In a definition file there also many keywords are available. See an example then expand the meanings:
target: null
rulefile: MRTS_001_INIT.conf
testfile: null
objects:
- object: secaction
actions:
id: 10001
phase: 1
pass: null
nolog: null
msg: "'Initial settings'"
ctl: ruleEngine=DetectionOnly
- object: secrule
target: REQUEST_HEADERS:X-MRTS-Test
operator: '@rx ^.*$'
actions:
id: 10002
phase: 1
pass: null
t: none
log: null
msg: "'%{MATCHED_VAR}'"
or
target: ARGS_COMBINED_SIZE
rulefile: MRTS_003_ARGS_COMBINED_SIZE.conf
testfile: MRTS_003_ARGS_COMBINED_SIZE.yaml
templates:
- SecRule for TARGETS
colkey:
- - ''
operator:
- '@lt'
oparg:
- 2
actions:
- action:
- status:404
directives:
- directive:
- SecAction "id:$CURRID,phase:$PHASE, pass, setenv:'123=abc'"
testdata:
phase_methods:
1: get
2: post
3: post
4: post
targets:
- target: 2
test:
data:
foo: attack
- target: arg1
test:
data:
arg1: attack
- target: arg2
test:
data:
arg2: attack
target
- defines the variable name what you want to test; it can be null, but then you must define the expected rules or actions under theobject
blockrulefile
- the name of generated file; the path will be passed as cli argument, you should define here the relative pathtestfile
- the name of generated test file; can be null if you don't want to make tests against rules. The path here also will be passed as cli argument.objects
- a list type item, you can order theobject
which describes aSecRule
or aSecAction
. This is necessary because there are some special rules/actions, which can't described as regular rule. The first example generates the fileMRTS_001_INIT.conf
with aSecAction
and aSecRule
:
SecAction \
"id:10001,\
phase:1,\
pass,\
nolog,\
msg:'Initial settings',\
ctl:ruleEngine=DetectionOnly"
SecRule REQUEST_HEADERS:X-MRTS-Test "@rx ^.*$"\
"id:10002,\
phase:1,\
pass,\
t:none,\
log,\
msg:'%{MATCHED_VAR}'"
These are necessary for go-ftw
.
templates
- you can list the name of templates what you want to applycolkey
- list collection keys what you want to test; note that each item in the list is a list too! See this example:
colkey:
- - ''
- - arg1
- - arg1
- arg2
- - /^arg_.*$/
will produce: [[''], ['arg1'], ['arg2'], ['arg1', 'arg2'], ['/^arg_.*$']]
. This will generate rules with targets:
SecRule ARGS
SecRule ARGS:arg1
SecRule ARGS:arg1|ARGS:arg2
SecRule ARGS:/^arg_.*$/
operator
- list of used operatorsoparg
- list of used operator argumentsactions
- list of used actions - see actions sectiondirectives
- list of used directives - see directives sectiontestdata
- list of expected test cases - see testdata section
actions
are defined for the $ACTIONS
macro. See this example:
actions:
- action:
- setvar:ABC=1
- auditlog
- status:400
- action:
- setvar:XYZ=2
- status:500
Each action
field contains a list of actions to be included in a SecRule/SecAction. Every action
list will be used to generate different combinations of rules.
The above example used with this template:
template: |
SecRule ${TARGET}$ "${OPERATOR}$ ${OPARG}$" \
"id:${CURRID}$,\
phase:${PHASE}$,\
deny,\
t:none,\
log,\
msg:'%{MATCHED_VAR_NAME} was caught in phase:${PHASE}$',\
ver:'${VERSION}$',\
${ACTIONS}$"
would produce the following rules:
SecRule ARGS "@contains attack" \
"id:100000,\
phase:2,\
deny,\
t:none,\
log,\
msg:'%{MATCHED_VAR_NAME} was caught in phase:2',\
ver:'MRTS/0.1',\
setvar:ABC=1,\
auditlog,\
status:400"
SecRule ARGS "@contains attack" \
"id:100001,\
phase:2,\
deny,\
t:none,\
log,\
msg:'%{MATCHED_VAR_NAME} was caught in phase:2',\
ver:'MRTS/0.1',\
setvar:XYZ=2,\
status:500"
directives
are defined for the ${DIRECTIVES}$
macro. See this example:
directives:
- directive:
- SecAction "id:$CURRID,phase:$PHASE, pass, setenv:'123=abc'"
- SecAction "id:$CURRID,phase:$PHASE, pass, setenv:'456=def'"
- directive:
- SecAction "id:$CURRID,phase:$PHASE, pass, setenv:'789=xyz'"
Each directive
field contains a list of directives to be included in a template. Every directive
list will be used to generate different combinations of rules. Macros are available and will be replaced with the current combination's value, except for macro $CURRID
that is instead incremented at each substitution to guarantee a unique id per SecRule/SecAction.
The above example used with this template:
template: |
SecRule ${TARGET}$ "$OPERATOR $OPARG" \
"id:${CURRID}$,\
phase:${PHASE}$,\
deny,\
t:none,\
log,\
msg:'%{MATCHED_VAR_NAME} was caught in phase:${PHASE}$',\
ver:'${VERSION}$'"
${DIRECTIVES}$
would produce the following rules:
SecRule ARGS "@contains attack" \
"id:100000,\
phase:2,\
t:none,\
log,\
msg:'%{MATCHED_VAR_NAME} was caught in phase:2',\
ver:'MRTS/0.1'"
SecAction "id:100001,phase:2, pass, setenv:'123=abc'"
SecAction "id:100002,phase:2, pass, setenv:'456=def'"
SecRule ARGS "@contains attack" \
"id:100003,\
phase:2,\
t:none,\
log,\
msg:'%{MATCHED_VAR_NAME} was caught in phase:2',\
ver:'MRTS/0.1'"
SecAction "id:100004,phase:2, pass, setenv:'789=xyz'"
testdata
is a keyword in the definition file. Here you can list the necessary test case definitions. A testdata item can contain two member:
phase_methods
- where you can overwrite the default_tests_phase_methods - this keyword is optionaltargets
- here you can define the posible collection keys that can occurres in generated rules
Let's see a test case definition example:
targets:
- target: ''
test:
data:
foo: attack
- target: arg1
test:
data:
arg1: attack
As it described above, targets
is list of tests. A test case contains two keywords:
target
- describes the collection key which used at the rule (can be empty: ``)test
- is an object
The test
object can contains these keywords:
data
- which can be a single string or a key:value pairinput
- a structure which overrides the test case in predefined structure
Note, that the go-ftw
test structure is hard-coded in the script, the input
overwrites that structure.
The given example above contains two test cases: one if the collection key is empty, and another one if the collection key is the arg1
- see the generated rules example above. You must give at least one test for each used collection keys at the rules definition!
Here are some examples for test cases:
targets:
- target: ''
test:
data:
foo: attack
- target: ''
test:
data:
arg1: attack
This will generate two test cases for empty collection key with data: foo=attack
and arg1=attack
.
- target: ''
test:
data:
foo: attack
- target: arg1
test:
data:
arg1: attack
This will generate one test for empty collection key and one for the collection key arg1
. The data for the first case will be foo=attack
and arg1=attack
for the second.
targets:
- target: '/*'
test:
data:
<level1><level2>foo</level2><level2>bar</level2></level1>
input:
headers:
- name: Content-Type
value: application/xml
This will generate a test case for collection key /*
(usually used for XML
), the data will be the given XML
string, and the test add an extra header for go-ftw
test.
The field input.encoded_request
allows defining a whole request encoded in base64. When running the test, the request is decoded into bytes and sent verbatim as the input for this test case. This allows sending malformed requests. Using this field will override all other fields related to the request.
targets:
- target: ''
test:
data: null
input:
encoded_request: R0VUIC8gSFRUUC8xLjENCkhvc3Q6IGxvY2FsaG9zdA0KDQo=
The yaml schema has a mechanism to handle global and local constants.
global:
default_constants:
one: 1
TWO: 2
two_in_list:
- 2
FOO_IN_DICT:
foo: attack
...
constants:
HEADERS_IN_DICTIONARY:
headers:
- name: test
value: test
- name: one
value: ~{one}~
- name: 2
value: ~{TWO}~
template_in_list:
- SecRule for TARGETS
- Template with constants
one: one
Global constants are defined under the global.default_constants
field. They are accessible across files and are reset whenever a new global
field is defined.
Local constants are defined under a constants
field at the root of a file. They are only accessible in the file they are defined in.
Constants are defined as key-value pairs where:
NAME: VALUE
The name is used for referencing the constant and the value is used for the substitution. Referencing a constant can be done inside the value of any other key in the API. References use the ~{...}~
separators like so:
~{NAME}~
Variable names can be lower or upper case and are case sensitive.
Constants can be yaml scalars, lists, or dictionaries:
scalar: 1
list:
- 1
dictionary:
1: 1
Constants can reference other constants in their values:
headers:
- name: one
value: ~{one}~
- name: two
value: ~{TWO}~
Local constants with the same name as global constants have precedence in their local scope:
global:
default_constants:
ONE: 1
...
constants:
ONE: one
...
key: ~{ONE}~ # substituted by 'one'
Values can contain multiple references, such as in templates:
- name: "Template with constants"
template: |
SecRule ~{target}~ "${OPERATOR}$ ${OPARG}$" \
"id:${CURRID}$,\
phase:${PHASE}$,\
deny,\
t:~{None}~,\
log,\
msg:'%{MATCHED_VAR_NAME} was caught in phase:${PHASE}$',\
ver:'~{VERSION}~'"
By default, the generator will produce checks for tests with go-ftw
's expect_ids
field using the current rule id as parameter. If the associated rule matches and it's id put in the log, the test will pass.
To use additional check methods, the output
field can be used to redefine this default behavior:
targets:
- target:
test:
data:
foo: attack
output:
status: 200
This will use the status
check. The available checks are (as of version 2.1.1 of the go-ftw
yaml schema specs):
status
- the expected HTTP status coderesponse_contains
- a regex match on the response[no_]log_contains
- a string match on the loglog.[no_]expect_ids
- a list of expected rule ids in the loglog.[no_]match_regex
- a regex match on the logexpect_error
- expect an error from the waf
For a full syntax of:
output:
status: 200
response_contains: HTTP/1.1
log_contains: nothing
no_log_contains: everything
log:
expect_ids:
- 123456
no_expect_ids:
- 123456
match_regex: id[:\s"]*123456
no_match_regex: id[:\s"]*123456
expect_error: true
To combine the default check on the current rule id with additional checks, the expect_ids
field must be used in conjunction with the output
field:
output:
status: 200
log:
expect_ids: []
This way, the status check will be used in addition to the default rule id check.
Exact properties, syntax, available checks and parameters are dependent on the used version of go-ftw
. The generator will simply replace what is defined under the output
field in the corresponding field of the generated test case.
As described for go-ftw
, if any of the checks fail the test will fail.
To generate the rules and their tests, run the tool:
$ ./generate-rules.py
usage: generate-rules.py [-h] -r [/path/to/mrts/*.yaml ...] -e /path/to/mrts/rules/ -t /path/to/mrts/tests/
generate-rules.py: error: the following arguments are required: -r/--rulesdef, -e/--expdir, -t/--testdir
As you can see there are few command line arguments.
-r
- rules' definition files-e
- export directory where rules will be written-t
- export test directory where tests will be written
$ ./mrts/generate-rules.py -r config_tests/*.yaml -e generated/rules/ -t generated/tests/regression/tests/
Once generated, rules need to be added to your ModSecurity configuration file.
Change mΜrts.load
with your absolute path to the generated rules:
Include /Absolute/Path/To/MRTS/generated/rules/*.conf
In modsecurity.conf
include your absolute path to mrts.load
:
...
Include /Absolute/Path/To/MRTS/mrts.load
Don't forget to restart your server each time you generate new rules.
If you finished the generation and configuration process, you can download go-ftw
and run it.
For more info about go-ftw
please see its README or CRS's excellent documentation.
Here is an example:
$ cat .ftw.apache-mrts.yaml
---
logfile: '/var/log/apache2/error.log'
logmarkerheadername: 'X-MRTS-TEST'
logtype:
name: 'apache'
timeregex: '\[([A-Z][a-z]{2} [A-z][a-z]{2} \d{1,2} \d{1,2}\:\d{1,2}\:\d{1,2}\.\d+? \d{4})\]'
timeformat: 'ddd MMM DD HH:mm:ss.S YYYY'
$ ./go-ftw run --config .ftw.apache-mrts.yaml -d generated/tests/regression/tests/
π οΈ Starting tests!
π Running go-ftw!
π executing tests in file MRTS_002_ARGS.yaml
running 2-1: β passed in 12.842548ms (RTT 54.970028ms)
running 2-2: β passed in 12.049459ms (RTT 54.891019ms)
running 2-3: β passed in 10.790834ms (RTT 53.365412ms)
running 2-4: β passed in 10.695786ms (RTT 53.515826ms)
π executing tests in file MRTS_002_ARGS.yaml
running 2-1: β passed in 8.615306ms (RTT 52.334647ms)
running 2-2: β passed in 7.64326ms (RTT 52.301444ms)
running 2-3: β passed in 8.353395ms (RTT 52.289161ms)
running 2-4: β passed in 8.704224ms (RTT 52.993254ms)
...
When you finished the build process, you can check which variables (and later the other entities) are covered by the generated rule set.
You should type:
$ cd mrts/collect_rules
$ ./collect-rules.py
usage: collect-rules.py [-h] -r [/path/to/mrts/*.conf ...]
collect-rules.py: error: the following arguments are required: -r/--rules
As you can see here are also a mandatory argument, the path of generated rules.
$ ./collect-rules.py -r ../../generated/rules/*.conf
Config file: ../../generated/rules/MRTS_001_INIT.conf
Parsing ok.
Config file: ../../generated/rules/MRTS_002_ARGS.conf
Parsing ok.
Config file: ../../generated/rules/MRTS_003_ARGS_COMBINED_SIZE.conf
Parsing ok.
Config file: ../../generated/rules/MRTS_004_ARGS_GET.conf
Parsing ok.
Config file: ../../generated/rules/MRTS_005_ARGS_GET_NAMES.conf
Parsing ok.
Config file: ../../generated/rules/MRTS_110_XML.conf
Parsing ok.
=====
Covered TARGETs: REQUEST_HEADERS, ARGS, ARGS_COMBINED_SIZE, ARGS_GET, ARGS_GET_NAMES, XML
UNCOVERED TARGETs: ARGS_NAMES, ARGS_POST, ARGS_POST_NAMES, ...
Based on the output, we actually covered 6 targets, so there are lot of works to cover all variables.