Fuzz introspector
For issues and ideas: https://github.com/ossf/fuzz-introspector/issues
Project coverage

Table of contents

Project overview: urllib3
High level conclusions
Reachability and coverage overview
Fuzzers overview
Project functions overview
Fuzzer details
Fuzzer: fuzz_urlparse
Call tree
Runtime coverage analysis
Files reached
Fuzzer: fuzz_requests
Call tree
Fuzz blockers
Runtime coverage analysis
Files reached
Analyses and suggestions
Optimal target analysis
Remaining optimal interesting functions
All functions overview
Runtime coverage analysis
Complex functions with low coverage
Files and Directories in report
Files in report
Directories in report
Metadata section
Function call coverage
Function in each files in report
Report generation date: 2023-06-07

Project overview: urllib3

High level conclusions

Reachability and coverage overview

Functions statically reachable by fuzzers
14.0%
58 / 409
Cyclomatic complexity statically reachable by fuzzers
16.0%
231 / 1442
Runtime code coverage of functions
18.0%
72 / 409

Warning: The number of runtime covered functions are larger than the number of reachable functions. This means that Fuzz Introspector found there are more functions covered at runtime than what is considered reachable based on the static analysis. This is a limitation in the analysis as anything covered at runtime is by definition reachable by the fuzzers.
This is likely due to a limitation in the static analysis. In this case, the count of functions covered at runtime is the true value, which means this is what should be considered "achieved" by the fuzzer.

Use the project functions table below to query all functions that were not covered at runtime.

Fuzzers overview

Fuzzer Fuzzer filename Functions Reached Functions unreached Fuzzer depth Files reached Basic blocks reached Cyclomatic complexity Details
fuzz_urlparse /src/fuzz_urlparse.py 4 859 1 2 0 9 fuzz_urlparse.py
fuzz_requests /src/fuzz_requests.py 182 710 8 15 148 601 fuzz_requests.py

Project functions overview

The following table shows data about each function in the project. The functions included in this table correspond to all functions that exist in the executables of the fuzzers. As such, there may be functions that are from third-party libraries.

For further technical details on the meaning of columns in the below table, please see the Glossary .

Func name Functions filename Args Function call depth Reached by Fuzzers Fuzzers runtime hit Func lines hit % I Count BB Count Cyclomatic complexity Functions reached Reached by functions Accumulated cyclomatic complexity Undiscovered complexity

Fuzzer details

Fuzzer: fuzz_urlparse

Call tree

The calltree shows the control flow of the fuzzer. This is overlaid with coverage information to display how much of the potential code a fuzzer can reach is in fact covered at runtime. In the following there is a link to a detailed calltree visualisation as well as a bitmap showing a high-level view of the calltree. For further information about these topics please see the glossary for full calltree and calltree overview

Full calltree

Call tree overview bitmap:

The distribution of callsites in terms of coloring is
Color Runtime hitcount Callsite count Percentage
red 0 0 0.0%
gold [1:9] 0 0.0%
yellow [10:29] 0 0.0%
greenyellow [30:49] 0 0.0%
lawngreen 50+ 4 100.%
All colors 4 100

Runtime coverage analysis

Covered functions
98
Functions that are reachable but not covered
4
Reachable functions
4
Percentage of reachable functions covered
0.0%
NB: The sum of covered functions and functions that are reachable but not covered need not be equal to Reachable functions . This is because the reachability analysis is an approximation and thus at runtime some functions may be covered that are not included in the reachability analysis. This is a limitation of our static analysis capabilities.
Warning: The number of covered functions are larger than the number of reachable functions. This means that there are more functions covered at runtime than are extracted using static analysis. This is likely a result of the static analysis component failing to extract the right call graph or the coverage runtime being compiled with sanitizers in code that the static analysis has not analysed. This can happen if lto/gold is not used in all places that coverage instrumentation is used.
Function name source code lines source lines hit percentage hit

Files reached

filename functions hit
/ 1
...fuzz_urlparse 3

Fuzzer: fuzz_requests

Call tree

The calltree shows the control flow of the fuzzer. This is overlaid with coverage information to display how much of the potential code a fuzzer can reach is in fact covered at runtime. In the following there is a link to a detailed calltree visualisation as well as a bitmap showing a high-level view of the calltree. For further information about these topics please see the glossary for full calltree and calltree overview

Full calltree

Call tree overview bitmap:

The distribution of callsites in terms of coloring is
Color Runtime hitcount Callsite count Percentage
red 0 266 84.7%
gold [1:9] 0 0.0%
yellow [10:29] 0 0.0%
greenyellow [30:49] 0 0.0%
lawngreen 50+ 48 15.2%
All colors 314 100

Fuzz blockers

The following nodes represent call sites where fuzz blockers occur.

Amount of callsites blocked Calltree index Parent function Callsite Largest blocked function
159 154 urllib3.util.retry.Retry.__init__ call site: 00154 urllib3._request_methods.RequestMethods.request_encode_body
64 4 urllib3.poolmanager.PoolManager.__init__ call site: 00004 urllib3._request_methods.RequestMethods.request
37 115 urllib3.util.url.parse_url call site: 00115 urllib3.poolmanager.PoolManager.urlopen
2 100 urllib3.util.url._idna_encode call site: 00100 name.lower
1 0 EP call site: 00000 urllib3.poolmanager.PoolManager.__init__
1 84 urllib3.util.url._encode_invalid_chars call site: 00084 byte.decode
1 98 urllib3.util.url._normalize_host call site: 00098 urllib3.util.url._idna_encode
1 103 urllib3.util.url._idna_encode call site: 00103 host.split

Runtime coverage analysis

Covered functions
100
Functions that are reachable but not covered
168
Reachable functions
182
Percentage of reachable functions covered
7.69%
NB: The sum of covered functions and functions that are reachable but not covered need not be equal to Reachable functions . This is because the reachability analysis is an approximation and thus at runtime some functions may be covered that are not included in the reachability analysis. This is a limitation of our static analysis capabilities.
Function name source code lines source lines hit percentage hit

Files reached

filename functions hit
/ 1
...fuzz_requests 17
urllib3.poolmanager 34
urllib3._collections 16
urllib3._request_methods 14
urllib3.util.url 39
urllib3.util.util 1
urllib3.util.retry 7
urllib3.connectionpool 52
urllib3.util.request 4
urllib3.util.timeout 6
urllib3.connection 3
urllib3.exceptions 1
urllib3.filepost 12
urllib3.fields 9

Analyses and suggestions

Optimal target analysis

Remaining optimal interesting functions

The following table shows a list of functions that are optimal targets. Optimal targets are identified by finding the functions that in combination, yield a high code coverage.

Func name Functions filename Arg count Args Function depth hitcount instr count bb count cyclomatic complexity Reachable functions Incoming references total cyclomatic complexity Unreached complexity
urllib3.contrib.securetransport.WrappedSocket.handshake urllib3.contrib.securetransport 10 ['N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A'] 2 0 11 6 5 89 1 284 269
urllib3.response.HTTPResponse.__iter__ urllib3.response 1 ['N/A'] 4 0 4 3 4 66 0 228 207
urllib3.connection.HTTPSConnection.connect urllib3.connection 1 ['N/A'] 3 0 2 4 5 66 0 225 195
urllib3.connection.HTTPConnection.request urllib3.connection 9 ['N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A'] 2 0 11 14 9 30 1 105 74
urllib3.util.retry.Retry.sleep urllib3.util.retry 2 ['N/A', 'N/A'] 3 0 2 2 4 20 0 66 48
urllib3.util.connection.create_connection urllib3.util.connection 4 ['N/A', 'N/A', 'N/A', 'N/A'] 1 0 7 5 5 12 2 41 38
urllib3.util.wait.wait_for_socket urllib3.util.wait 4 ['N/A', 'N/A', 'N/A', 'N/A'] 1 0 0 2 4 12 3 42 36

Implementing fuzzers that target the above functions will improve reachability such that it becomes:

Functions statically reachable by fuzzers
36.0%
148 / 409
Cyclomatic complexity statically reachable by fuzzers
41.0%
585 / 1442

All functions overview

If you implement fuzzers for these functions, the status of all functions in the project will be:

Func name Functions filename Args Function call depth Reached by Fuzzers Fuzzers runtime hit Func lines hit % I Count BB Count Cyclomatic complexity Functions reached Reached by functions Accumulated cyclomatic complexity Undiscovered complexity

Runtime coverage analysis

This section shows analysis of runtime coverage data.

For futher technical details on how this section is generated, please see the Glossary .

Complex functions with low coverage

Func name Function total lines Lines covered at runtime percentage covered Reached by fuzzers
urllib3.poolmanager.PoolManager.urlopen 40 2 5.0% ['fuzz_requests']
urllib3.response.BytesQueueBuffer.get 36 8 22.22% []
urllib3.response.HTTPResponse.read 31 0 0.0% []
urllib3.response.HTTPResponse.read_chunked 33 2 6.060% []
urllib3.connection.HTTPConnection.request 41 0 0.0% []
urllib3.util.connection.create_connection 31 0 0.0% []
urllib3.util.ssl_._is_has_never_check_common_name_reliable 32 16 50.0% []
urllib3.util.ssl_.create_urllib3_context 46 4 8.695% []
urllib3.util.ssl_match_hostname.match_hostname 31 0 0.0% []
urllib3.util.retry.Retry.increment 47 0 0.0% []
urllib3.connectionpool.HTTPConnectionPool._make_request 39 0 0.0% ['fuzz_requests']
urllib3.connectionpool.HTTPConnectionPool.urlopen 94 4 4.255% ['fuzz_requests']
urllib3.util.ssltransport.SSLTransport.makefile 32 0 0.0% []
urllib3._base_connection 34 18 52.94% []

Files and Directories in report

This section shows which files and directories are considered in this report. The main reason for showing this is fuzz introspector may include more code in the reasoning than is desired. This section helps identify if too many files/directories are included, e.g. third party code, which may be irrelevant for the threat model. In the event too much is included, fuzz introspector supports a configuration file that can exclude data from the report. See the following link for more information on how to create a config file: link

Files in report

Source file Reached by Covered by
[] []
weakref [] []
...fuzz_urlparse ['fuzz_urlparse'] []
urllib3.poolmanager ['fuzz_requests'] []
urllib3._collections ['fuzz_requests'] []
urllib3 [] []
urllib3._request_methods ['fuzz_requests'] []
urllib3.contrib._securetransport [] []
urllib3.contrib._securetransport.bindings [] []
urllib3.util.proxy [] []
urllib3.util.util ['fuzz_requests'] []
urllib3.connectionpool ['fuzz_requests'] []
ctypes [] []
http [] []
datetime [] []
urllib3.util.request ['fuzz_requests'] []
urllib3.util.retry ['fuzz_requests'] []
enum [] []
struct [] []
urllib3.fields ['fuzz_requests'] []
urllib3.exceptions ['fuzz_requests'] []
_collections [] []
base64 [] []
OpenSSL [] []
idna [] []
urllib [] []
os [] []
urllib3.contrib.pyopenssl [] []
urllib3.contrib.securetransport [] []
io [] []
platform [] []
re [] []
urllib3.contrib.socks [] []
select [] []
urllib3.contrib._securetransport.low_level [] []
urllib3.util.response [] []
functools [] []
random [] []
hmac [] []
urllib3.util.ssltransport [] []
brotlicffi [] []
urllib3._version [] []
binascii [] []
typing [] []
sys [] []
urllib3.util.ssl_match_hostname [] []
codecs [] []
urllib3._base_connection [] []
ipaddress [] []
threading [] []
socket [] []
...fuzz_requests ['fuzz_requests'] []
urllib3.util [] []
logging [] []
shutil [] []
[] []
urllib3.util.url ['fuzz_requests'] []
itertools [] []
time [] []
email [] []
urllib3.contrib [] []
queue [] []
json [] []
warnings [] []
urllib3.util.timeout ['fuzz_requests'] []
zlib [] []
tempfile [] []
mimetypes [] []
zstandard [] []
collections [] []
urllib3.util.wait [] []
ssl [] []
urllib3.response [] []
atheris [] []
urllib3.connection ['fuzz_requests'] []
urllib3.util.connection [] []
urllib3.filepost ['fuzz_requests'] []
urllib3.util.ssl_ [] []
brotli [] []
socks [] []

Directories in report

Directory

Metadata section

This sections shows the raw data that is used to produce this report. This is mainly used for further processing and developer debugging.

Fuzzer Calltree file Program data file Coverage file
fuzz_urlparse fuzzerLogFile-fuzz_urlparse.data fuzzerLogFile-fuzz_urlparse.data.yaml all_cov.json
fuzz_requests fuzzerLogFile-fuzz_requests.data fuzzerLogFile-fuzz_requests.data.yaml all_cov.json