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

Table of contents

Project overview: pyasn1-modules
High level conclusions
Reachability and coverage overview
Fuzzers overview
Project functions overview
Fuzzer details
Fuzzer: fuzz_decode
Call tree
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: 2023-03-26

Project overview: pyasn1-modules

High level conclusions

Reachability and coverage overview

Functions statically reachable by fuzzers
0.47%
4/860
Cyclomatic complexity statically reachable by fuzzers
0.43%
12/2815
Runtime code coverage of functions
65.0%
556 / 860

Fuzzers overview

Fuzzer Fuzzer filename Functions Reached Functions unreached Fuzzer depth Files reached Basic blocks reached Cyclomatic complexity Details
fuzz_decode /src/fuzz_decode.py 5 882 1 2 0 12 fuzz_decode.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_decode

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+ 5 100.%
All colors 5 100

Runtime coverage analysis

Covered functions
212
Functions that are reachable but not covered
4
Reachable functions
5
Percentage of reachable functions covered
20.0%
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_decode 4

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
pyasn1.codec.ber.encoder.AbstractItemEncoder.encode pyasn1.codec.ber.encoder 5 ['N/A', 'N/A', 'N/A', 'N/A', 'N/A'] 3 0 4 13 8 66 0 242 242
pyasn1.type.univ.BitString.__init__ pyasn1.type.univ 3 ['N/A', 'N/A', 'N/A'] 4 0 1 6 5 48 1 163 115
pyasn1.codec.ber.decoder.Decoder.__call__ pyasn1.codec.ber.decoder 9 ['N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A'] 4 0 22 49 23 43 0 164 110
pyasn1.codec.ber.decoder.UniversalConstructedTypeDecoder.valueDecoder pyasn1.codec.ber.decoder 9 ['N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A'] 2 0 16 30 15 38 0 132 58
pyasn1.type.namedtype.NamedTypes.__computeAmbiguousTypes pyasn1.type.namedtype 1 ['N/A'] 4 0 0 2 4 21 6 71 50
pyasn1.codec.ber.decoder.ChoiceDecoder.valueDecoder pyasn1.codec.ber.decoder 9 ['N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A'] 4 0 4 6 5 23 0 86 48
pyasn1.type.useful.TimeMixIn.asDateTime pyasn1.type.useful 1 ['N/A'] 1 0 1 10 7 14 0 49 40

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

Functions statically reachable by fuzzers
19.8%
171/860
Cyclomatic complexity statically reachable by fuzzers
22.5%
635 / 2815

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
pyasn1_modules.pem.readBase64fromText 39 9 23.07% ['fuzz_decode']
pyasn1.codec.ber.decoder.UniversalConstructedTypeDecoder.valueDecoder 102 8 7.843% []
pyasn1.codec.ber.decoder.UniversalConstructedTypeDecoder.indefLenValueDecoder 120 16 13.33% []
pyasn1.type.univ.BitString.prettyIn 37 18 48.64% []
pyasn1.type.univ.OctetString.__init__ 36 17 47.22% []
pyasn1.type.univ.SequenceOfAndSetOfBase.setComponentByPosition 34 13 38.23% []
pyasn1.type.univ.SequenceOfAndSetOfBase.isInconsistent 31 16 51.61% []
pyasn1.type.univ.SequenceAndSetBase.setComponentByPosition 44 19 43.18% []
pyasn1.type.namedval.NamedValues.__init__ 32 13 40.62% []
pyasn1.compat.integer 59 6 10.16% []
pyasn1.type.useful.TimeMixIn.asDateTime 38 0 0.0% []

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
[] []
pyasn1.type.tagmap [] []
pyasn1.type.opentype [] []
pyasn1.codec.ber.eoo [] []
pyasn1.compat.dateandtime [] []
pyasn1.codec.native [] []
atheris [] []
pyasn1.debug [] []
pyasn1.compat.octets [] []
pyasn1.codec.native.decoder [] []
pyasn1.compat.integer [] []
pyasn1.codec.native.encoder [] []
pyasn1.type.constraint [] []
binascii [] []
pyasn1 [] []
pyasn1.codec.cer.encoder [] []
pyasn1.type.tag [] []
pyasn1.compat [] []
pyasn1.error [] []
sys [] []
pyasn1.codec [] []
pyasn1.type.base [] []
pyasn1.codec.der.decoder [] []
pyasn1.type [] []
pyasn1.codec.der [] []
pyasn1.compat.calling [] []
pyasn1.compat.binary [] []
...fuzz_decode ['fuzz_decode'] []
pyasn1_modules [] []
[] []
pyasn1.type.error [] []
pyasn1.compat.string [] []
pyasn1.codec.der.encoder [] []
pyasn1.codec.ber.decoder [] []
pyasn1.type.namedval [] []
pyasn1.codec.cer.decoder [] []
pyasn1.type.char [] []
pyasn1.type.namedtype [] []
pyasn1.codec.cer [] []
math [] []
pyasn1.codec.ber.encoder [] []
platform [] []
pyasn1.codec.ber [] []
logging [] []
datetime [] []
pyasn1.type.univ [] []
time [] []
pyasn1.type.useful [] []
collections [] []

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_decode fuzzerLogFile-fuzz_decode.data fuzzerLogFile-fuzz_decode.data.yaml all_cov.json

Function call coverage

This section shows a chosen list of functions / methods calls and their relative coverage information. By static analysis of the target project code, all of these function call and their caller information, including the source file or class and line number that initiate the call are captured. Column 1 is the function name of that selected functions or methods. Column 2 of each row indicate if the target function covered by any fuzzer calltree information. Column 3 lists all fuzzers (or no fuzzers at all) that have coered that particular function call dynamically. Column 4 shows list of parent function for the specific function call, while column 5 shows possible blocker functions that make the fuzzers fail to reach the specific functions. Both column 4 and 5 will only show information if none of the fuzzers cover the target function calls.

Function in each files in report

Target sink Callsite location Reached by fuzzer Function call path Covered by fuzzer Possible branch blockers