High level conclusions

Fuzzers reach 66.45% code coverage.

Fuzzers reach 84.94% of cyclomatic complexity.

Fuzzers reach 75.16% of all functions.

Reachability and coverage overview

Functions statically reachable by fuzzers

233 / 310

Cyclomatic complexity statically reachable by fuzzers

2798 / 3294

Runtime code coverage of functions

206 / 310

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: table_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	598	84.3%
gold	[1:9]	98	13.8%
yellow	[10:29]	5	0.70%
greenyellow	[30:49]	2	0.28%
lawngreen	50+	6	0.84%
All colors	709	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
446	207	addBackwardRuleWithSingleCell	call site: 00207	compileRule
25	75	parseCharsInternal	call site: 00075	_lou_getALine
17	188	addForwardRuleWithSingleChar	call site: 00188	_lou_logMessage
13	19	getLogLevelFromEnvironment	call site: 00019	_lou_logMessage
13	102	getAChar	call site: 00102	_lou_getALine
12	57	compileRule	call site: 00057	compileHyphenation
10	149	getRuleDotsPattern	call site: 00149	compileError
8	655	compileFile	call site: 00655	_lou_logMessage
6	33	rpl_free	call site: 00033	_lou_outOfMemory
5	137	compileFile	call site: 00137	compileError
5	668	compileTable	call site: 00668	compileFile
4	70	parseCharsInternal	call site: 00070	compileWarning

Runtime coverage analysis

Covered functions

56

Functions that are reachable but not covered

79

Reachable functions

132

Percentage of reachable functions covered

40.15%

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/liblouis/tests/fuzzing/table_fuzzer.cc	1
/src/liblouis/liblouis/compileTranslationTable.c	93
/src/liblouis/liblouis/logging.c	5
/src/liblouis/tools/gnulib/free.c	1
/src/liblouis/liblouis/utils.c	5
/src/liblouis/liblouis/./internal.h	1
/src/liblouis/liblouis/pattern.c	8
/src/liblouis/liblouis/metadata.c	2

Fuzzer: fuzz_backtranslate

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	448	50.3%
gold	[1:9]	114	12.8%
yellow	[10:29]	55	6.17%
greenyellow	[30:49]	23	2.58%
lawngreen	50+	250	28.0%
All colors	890	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
51	589	compilePassOpcode	call site: 00589	addRule
38	221	compileRule	call site: 00221	compileRule
32	310	compileRule	call site: 00310	compileBrailleIndicator
20	402	compileRule	call site: 00402	compileBrailleIndicator
20	695	finalizeTable	call site: 00695	finalizeCharacter
18	439	compileRule	call site: 00439	addRule
13	533	findRuleName	call site: 00533	appendInstructionChar
11	377	compileRule	call site: 00377	compileBrailleIndicator
10	23	getLogLevelFromEnvironment	call site: 00023	_lou_logMessage
10	659	compileFile	call site: 00659	_lou_logMessage
10	760	_lou_backTranslate	call site: 00760	_lou_outOfMemory
9	789	back_selectRule	call site: 00789	findBrailleIndicatorRule

Runtime coverage analysis

Covered functions

155

Functions that are reachable but not covered

41

Reachable functions

192

Percentage of reachable functions covered

78.65%

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/liblouis/tests/fuzzing/fuzz_backtranslate.c	2
/src/liblouis/liblouis/logging.c	6
/src/liblouis/liblouis/compileTranslationTable.c	100
/src/liblouis/tools/gnulib/free.c	1
/src/liblouis/liblouis/utils.c	7
/src/liblouis/liblouis/./internal.h	1
/src/liblouis/liblouis/pattern.c	15
/src/liblouis/liblouis/metadata.c	2
/src/liblouis/liblouis/lou_backTranslateString.c	37
/src/liblouis/liblouis/commonTranslationFunctions.c	3

Fuzzer: fuzz_translate_generic

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	491	44.7%
gold	[1:9]	187	17.0%
yellow	[10:29]	44	4.01%
greenyellow	[30:49]	32	2.91%
lawngreen	50+	342	31.2%
All colors	1096	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
32	401	compileRule	call site: 00401	compileBrailleIndicator
21	367	compileRule	call site: 00367	compileBrailleIndicator
17	242	compileGrouping	call site: 00242	compileRule
16	1033	insertNumberSign	call site: 01033	checkNumericMode
15	297	compileRule	call site: 00297	addRule
15	698	finalizeCharacter	call site: 00698	_lou_logMessage
14	988	insertEmphasesAt	call site: 00988	beginCount
12	192	addForwardRuleWithSingleChar	call site: 00192	_lou_logMessage
10	23	getLogLevelFromEnvironment	call site: 00023	_lou_logMessage
10	659	compileFile	call site: 00659	_lou_logMessage
9	595	compileRule	call site: 00595	addRule
9	891	translateString	call site: 00891	doCompTrans

Runtime coverage analysis

Covered functions

188

Functions that are reachable but not covered

57

Reachable functions

239

Percentage of reachable functions covered

76.15%

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/liblouis/tests/fuzzing/fuzz_translate_generic.c	2
/src/liblouis/liblouis/logging.c	7
/src/liblouis/liblouis/compileTranslationTable.c	100
/src/liblouis/tools/gnulib/free.c	1
/src/liblouis/liblouis/utils.c	8
/src/liblouis/liblouis/./internal.h	1
/src/liblouis/liblouis/pattern.c	15
/src/liblouis/liblouis/metadata.c	2
/src/liblouis/liblouis/lou_translateString.c	74
/src/liblouis/liblouis/commonTranslationFunctions.c	3

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
lou_findTables	/src/liblouis/liblouis/metadata.c	1	['N/A']	10	0	156	20	7	69	0	363	281
_lou_defaultTableResolver	/src/liblouis/liblouis/compileTranslationTable.c	2	['N/A', 'N/A']	5	0	218	36	12	22	0	102	42

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

Functions statically reachable by fuzzers

274 / 310

Cyclomatic complexity statically reachable by fuzzers

3103 / 3294

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

This sections provides heuristics that can be used as input to a fuzz engine when running a given fuzz target. The current focus is on providing input that is usable by libFuzzer.

/src/liblouis/tests/fuzzing/table_fuzzer.cc

Dictionary

Use this with the libFuzzer -dict=DICT.file flag

Fuzzer function priority

Use one of these functions as input to libfuzzer with flag: -focus_function name

-focus_function=['addBackwardRuleWithSingleCell', 'parseCharsInternal', 'addForwardRuleWithSingleChar', 'getLogLevelFromEnvironment', 'getAChar', 'compileRule', 'getRuleDotsPattern', 'compileFile', 'rpl_free']

/src/liblouis/tests/fuzzing/fuzz_backtranslate.c

Dictionary

Use this with the libFuzzer -dict=DICT.file flag

Fuzzer function priority

Use one of these functions as input to libfuzzer with flag: -focus_function name

-focus_function=['compilePassOpcode', 'compileRule', 'finalizeTable', 'findRuleName', 'getLogLevelFromEnvironment', 'compileFile']

/src/liblouis/tests/fuzzing/fuzz_translate_generic.c

Dictionary

Use this with the libFuzzer -dict=DICT.file flag

Fuzzer function priority

Use one of these functions as input to libfuzzer with flag: -focus_function name

-focus_function=['compileRule', 'compileGrouping', 'insertNumberSign', 'finalizeCharacter', 'insertEmphasesAt', 'addForwardRuleWithSingleChar', 'getLogLevelFromEnvironment', 'compileFile']

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
_lou_getTablePath	44	21	47.72%	['fuzz_backtranslate', 'table_fuzzer', 'fuzz_translate_generic']
resolveSubtable	66	23	34.84%	['fuzz_backtranslate', 'table_fuzzer', 'fuzz_translate_generic']
compileRule	1298	634	48.84%	['fuzz_backtranslate', 'table_fuzzer', 'fuzz_translate_generic']
getLogLevelFromEnvironment	35	5	14.28%	['fuzz_backtranslate', 'table_fuzzer', 'fuzz_translate_generic']
finalizeCharacter	104	38	36.53%	['fuzz_backtranslate', 'fuzz_translate_generic']
backTranslateString	260	138	53.07%	['fuzz_backtranslate']
handleMultind	49	3	6.122%	['fuzz_backtranslate']
findEmphasisClass	42	21	50.0%	['fuzz_backtranslate']
swapTest	49	22	44.89%	['fuzz_translate_generic']
markSyllables	66	10	15.15%	['fuzz_translate_generic']
resetsEmphMode	36	15	41.66%	['fuzz_translate_generic']
resolveEmphasisResets	122	52	42.62%	['fuzz_translate_generic']
for_selectRule	304	151	49.67%	['fuzz_translate_generic']
insertEmphasesAt	71	28	39.43%	['fuzz_translate_generic']
hyphenateWord	56	12	21.42%	['fuzz_translate_generic']

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/liblouis/liblouis/compileTranslationTable.c	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']
/src/liblouis/liblouis/metadata.c	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']
/src/liblouis/liblouis/logging.c	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']
/usr/local/bin/../include/c++/v1/stdexcept	[]	[]
/src/liblouis/liblouis/commonTranslationFunctions.c	['fuzz_backtranslate', 'fuzz_translate_generic']	['fuzz_backtranslate', 'fuzz_translate_generic']
/src/liblouis/liblouis/lou_translateString.c	['fuzz_translate_generic']	['fuzz_translate_generic']
/src/liblouis/liblouis/lou_backTranslateString.c	['fuzz_backtranslate']	['fuzz_backtranslate']
/src/liblouis/liblouis/./internal.h	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']	[]
/src/liblouis/tests/fuzzing/table_fuzzer.cc	['table_fuzzer']	['table_fuzzer']
/src/liblouis/liblouis/pattern.c	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']	['fuzz_backtranslate', 'fuzz_translate_generic']
/src/liblouis/tools/gnulib/free.c	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']
/src/liblouis/liblouis/utils.c	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']
/src/liblouis/tests/fuzzing/fuzz_backtranslate.c	['fuzz_backtranslate']	['fuzz_backtranslate']
/src/liblouis/tests/fuzzing/fuzz_translate_generic.c	['fuzz_translate_generic']	['fuzz_translate_generic']

Directories in report

Directory
/src/liblouis/tests/fuzzing/
/usr/local/bin/../include/c++/v1/
/src/liblouis/tools/gnulib/
/src/liblouis/liblouis/
/src/liblouis/liblouis/./