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

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 Runtime reached by Fuzzers Combined 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: wolfmqtt-fuzzer

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

Call tree overview bitmap:

The distribution of callsites in terms of coloring is
Color Runtime hitcount Callsite count Percentage
red 0 4768 94.3%
gold [1:9] 0 0.0%
yellow [10:29] 0 0.0%
greenyellow [30:49] 7 0.13%
lawngreen 50+ 279 5.52%
All colors 5054 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
4409 27 MqttSocket_Connect call site: 00027 wolfSSL_connect
261 4496 MqttSocket_WriteDo call site: 04496 wolfSSL_write
14 4762 MqttClient_Connect call site: 04762 MqttClient_AuthEx
10 4781 MqttSocket_ReadDo call site: 04781 wolfSSL_read
6 4458 MqttEncode_Data call site: 04458 MqttEncode_Utf8Ok
5 4450 MqttEncode_Connect call site: 04450 MqttEncode_Utf8Ok
4 4847 MqttDecode_SubscribeAck call site: 04847 MqttDecode_Props
4 4857 MqttDecode_UnsubscribeAck call site: 04857 MqttDecode_Props
3 4443 MqttClient_Connect call site: 04443 MqttReadStop
3 4472 MqttEncode_Connect call site: 04472 MqttEncode_Utf8Ok
3 4487 MqttEncode_Connect call site: 04487 MqttEncode_String
3 4833 MqttDecode_Publish call site: 04833 MqttDecode_Props

Runtime coverage analysis

Covered functions
120
Functions that are reachable but not covered
1291
Reachable functions
1431
Percentage of reachable functions covered
9.78%
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
/src/wolfmqtt-fuzzers/fuzzer.cpp 25
/src/fuzzing-headers/include/fuzzing/datasource/datasource.hpp 9
/src/wolfmqtt/src/mqtt_socket.c 9
/src/wolfmqtt/src/mqtt_client.c 33
/src/wolfssl/src/ssl.c 16
/src/wolfssl/wolfcrypt/src/wc_port.c 26
/src/wolfssl/wolfcrypt/src/random.c 32
/src/wolfssl/./src/ssl_sess.c 20
/src/wolfssl/./wolfcrypt/src/misc.c 46
/src/wolfssl/wolfcrypt/src/memory.c 2
/src/wolfssl/src/tls.c 137
/src/wolfssl/src/internal.c 242
/src/wolfssl/./src/ssl_certman.c 8
/src/wolfssl/wolfcrypt/src/asn.c 141
/src/wolfssl/wolfcrypt/src/dh.c 19
/src/wolfssl/wolfcrypt/src/sp_int.c 101
/src/wolfssl/wolfcrypt/src/wc_mlkem.c 21
/src/wolfssl/wolfcrypt/src/wc_mlkem_poly.c 62
/src/wolfssl/wolfcrypt/src/sha3.c 34
/src/wolfssl/wolfcrypt/src/ecc.c 63
/src/wolfssl/./src/ssl_api_cert.c 4
/src/wolfssl/./src/ssl_api_pk.c 1
/src/wolfssl/src/wolfio.c 6
/src/wolfssl/wolfcrypt/src/sha512.c 33
/src/wolfssl/wolfcrypt/src/sha256.c 17
/src/wolfssl/./src/ssl_api_ext.c 1
/src/wolfssl/wolfcrypt/src/aes.c 34
/src/wolfssl/wolfcrypt/src/rsa.c 35
/src/wolfssl/wolfcrypt/src/hash.c 15
/src/wolfssl/wolfcrypt/src/sha.c 7
/src/wolfssl/./src/ssl_api_hs.c 7
/src/wolfssl/src/tls13.c 70
/src/wolfssl/./wolfssl/wolfcrypt/types.h 1
/src/wolfssl/wolfcrypt/src/chacha20_poly1305.c 3
/src/wolfssl/wolfcrypt/src/chacha.c 5
/src/wolfssl/wolfcrypt/src/poly1305.c 14
/src/wolfssl/wolfcrypt/src/wolfmath.c 5
/src/wolfssl/src/keys.c 7
/src/wolfssl/wolfcrypt/src/kdf.c 4
/src/wolfssl/wolfcrypt/src/hmac.c 12
/src/wolfssl/./wolfssl/internal.h 1
/src/wolfssl/wolfcrypt/src/coding.c 1
/src/wolfssl/./src/x509_str.c 2
/src/wolfmqtt/src/mqtt_packet.c 42
/src/wolfssl/./src/ssl_api_rw.c 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
wolfSSL_CertManagerLoadCA /src/wolfssl/./src/ssl_certman.c 3 ['N/A', 'N/A', 'N/A'] 31 0 100 20 6 599 0 5373 515
wc_CreateEncryptedPKCS8Key /src/wolfssl/wolfcrypt/src/asn.c 14 ['N/A', 'int', 'N/A', 'N/A', 'N/A', 'int', 'int', 'int', 'int', 'N/A', 'int', 'int', 'N/A', 'N/A'] 21 0 54 3 2 296 0 2188 276
wolfSSL_ERR_error_string_n /src/wolfssl/./src/ssl_err.c 3 ['size_t', 'N/A', 'size_t'] 4 0 59 13 4 5 0 260 258
wolfSSL_CTX_check_private_key /src/wolfssl/./src/ssl_api_pk.c 1 ['N/A'] 21 0 77 12 5 483 0 4549 168
wc_Asn1_PrintAll /src/wolfssl/wolfcrypt/src/asn.c 4 ['N/A', 'N/A', 'N/A', 'int'] 9 0 186 33 13 43 0 431 141
TLS_hmac /src/wolfssl/src/tls.c 8 ['N/A', 'N/A', 'N/A', 'int', 'int', 'int', 'int', 'int'] 9 0 310 56 18 130 0 694 107
wolfSSL_CTX_SetTmpDH_file /src/wolfssl/./src/ssl_load.c 3 ['N/A', 'N/A', 'int'] 17 0 21 3 2 204 0 1951 86

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

Functions statically reachable by fuzzers
69.0%
1528 / 2216
Cyclomatic complexity statically reachable by fuzzers
81.0%
14575 / 18102

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 Runtime reached by Fuzzers Combined 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

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
[] []
/src/wolfssl/./src/ssl_api_dtls.c [] []
/src/wolfssl/./src/ssl_err.c [] []
/src/wolfssl/wolfcrypt/src/wc_mlkem_poly.c ['wolfmqtt-fuzzer'] []
/src/wolfmqtt-fuzzers/fuzzer.cpp ['wolfmqtt-fuzzer'] ['wolfmqtt-fuzzer']
/src/wolfmqtt/src/mqtt_client.c ['wolfmqtt-fuzzer'] ['wolfmqtt-fuzzer']
/src/wolfssl/./wolfssl/internal.h ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/sha3.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/src/tls.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/hmac.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/rsa.c ['wolfmqtt-fuzzer'] []
/usr/local/bin/../include/c++/v1/string [] []
/src/wolfssl/./src/ssl_certman.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/./src/ssl_load.c [] []
/src/fuzzing-headers/include/fuzzing/types.hpp [] []
/src/wolfssl/wolfcrypt/src/hash.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/wolfmath.c ['wolfmqtt-fuzzer'] []
/usr/local/bin/../include/c++/v1/__exception/exception.h [] []
/src/wolfssl/./src/ssl_api_ext.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/wc_encrypt.c [] []
/src/wolfmqtt/src/mqtt_socket.c ['wolfmqtt-fuzzer'] ['wolfmqtt-fuzzer']
/src/wolfssl/wolfcrypt/src/poly1305.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/./src/ssl_misc.c [] []
/src/wolfssl/wolfcrypt/src/chacha20_poly1305.c ['wolfmqtt-fuzzer'] []
/src/fuzzing-headers/include/fuzzing/datasource/datasource.hpp ['wolfmqtt-fuzzer'] ['wolfmqtt-fuzzer']
/src/wolfssl/./src/ssl_sess.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/kdf.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/coding.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/chacha.c ['wolfmqtt-fuzzer'] []
/src/fuzzing-headers/include/fuzzing/memory.hpp [] []
/src/wolfssl/wolfcrypt/src/asn.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/error.c [] []
/src/wolfssl/./src/ssl_api_cert.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/dh.c ['wolfmqtt-fuzzer'] []
/src/wolfmqtt/src/mqtt_packet.c ['wolfmqtt-fuzzer'] ['wolfmqtt-fuzzer']
/src/wolfssl/./src/ssl_api_hs.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/./src/x509.c [] []
/src/wolfssl/./src/x509_str.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/src/ssl.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/ecc.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/src/tls13.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/sha512.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/aes.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/pwdbased.c [] []
/src/wolfssl/./wolfcrypt/src/misc.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/src/internal.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/./wolfssl/wolfcrypt/types.h ['wolfmqtt-fuzzer'] []
/src/wolfssl/./src/ssl_api_pk.c ['wolfmqtt-fuzzer'] []
/usr/local/bin/../include/c++/v1/stdexcept [] []
/src/wolfssl/./src/pk.c [] []
/src/wolfssl/wolfcrypt/src/sp_int.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/sha256.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/wc_port.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/wc_mlkem.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/src/wolfio.c ['wolfmqtt-fuzzer'] []
/src/fuzzing-headers/include/fuzzing/exception.hpp [] []
/src/wolfssl/./src/ssl_api_rw.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/src/keys.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/sha.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/memory.c ['wolfmqtt-fuzzer'] []
/src/wolfssl/wolfcrypt/src/random.c ['wolfmqtt-fuzzer'] []

Directories in report

Directory
/src/wolfssl/src/
/src/wolfmqtt-fuzzers/
/src/fuzzing-headers/include/fuzzing/
/src/wolfssl/./wolfcrypt/src/
/src/wolfssl/./src/
/src/wolfssl/./wolfssl/wolfcrypt/
/src/wolfmqtt/src/
/src/fuzzing-headers/include/fuzzing/datasource/
/usr/local/bin/../include/c++/v1/__exception/
/src/wolfssl/wolfcrypt/src/
/usr/local/bin/../include/c++/v1/
/src/wolfssl/./wolfssl/