High level conclusions

Fuzzers reach 70.50% code coverage.

Fuzzers reach 85.50% of cyclomatic complexity.

Fuzzers reach 76.94% of all functions.

Reachability and coverage overview

Functions statically reachable by fuzzers

227 / 295

Cyclomatic complexity statically reachable by fuzzers

2749 / 3215

Runtime code coverage of functions

208 / 295

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	585	84.0%
gold	[1:9]	98	14.0%
yellow	[10:29]	5	0.71%
greenyellow	[30:49]	2	0.28%
lawngreen	50+	6	0.86%
All colors	696	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
442	197	addBackwardRuleWithSingleCell	call site: 00197	compileRule
25	65	parseChars	call site: 00065	_lou_getALine
17	178	addForwardRuleWithSingleChar	call site: 00178	_lou_logMessage
15	49	compileRule	call site: 00049	compileHyphenation
13	92	getAChar	call site: 00092	_lou_getALine
9	138	getRuleDotsPattern	call site: 00138	compileError
8	641	compileFile	call site: 00641	_lou_logMessage
6	25	rpl_free	call site: 00025	_lou_outOfMemory
5	19	getLogLevelFromEnvironment	call site: 00019	_lou_logMessage
5	126	compileFile	call site: 00126	compileError
5	654	compileTable	call site: 00654	compileFile
4	668	freeTranslationTable	call site: 00668	freeDisplayTable

Runtime coverage analysis

Covered functions

54

Functions that are reachable but not covered

76

Reachable functions

127

Percentage of reachable functions covered

40.16%

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	89
/src/liblouis/liblouis/logging.c	4
/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	297	33.7%
gold	[1:9]	134	15.2%
yellow	[10:29]	62	7.05%
greenyellow	[30:49]	49	5.57%
lawngreen	50+	337	38.3%
All colors	879	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	351	compileRule	call site: 00351	compileBrailleIndicator
17	232	compileGrouping	call site: 00232	compileRule
16	684	finalizeCharacter	call site: 00684	_lou_logMessage
12	746	_lou_backTranslate	call site: 00746	_lou_outOfMemory
11	400	compileRule	call site: 00400	compileBrailleIndicator
10	645	compileFile	call site: 00645	_lou_logMessage
7	412	compileRule	call site: 00412	compileBrailleIndicator
7	779	handleMultind	call site: 00779	findBrailleIndicatorRule
6	111	getOpcode	call site: 00111	includeFile
5	121	lou_freeTableFiles	call site: 00121	compileFile
5	130	compileFile	call site: 00130	compileError
5	332	compileRule	call site: 00332	compileBrailleIndicator

Runtime coverage analysis

Covered functions

162

Functions that are reachable but not covered

29

Reachable functions

187

Percentage of reachable functions covered

84.49%

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	5
/src/liblouis/liblouis/compileTranslationTable.c	96
/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	441	40.6%
gold	[1:9]	145	13.3%
yellow	[10:29]	76	7.00%
greenyellow	[30:49]	25	2.30%
lawngreen	50+	398	36.6%
All colors	1085	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
22	393	compileRule	call site: 00393	compileBrailleIndicator
21	360	compileRule	call site: 00360	compileBrailleIndicator
21	954	for_selectRule	call site: 00954	doCompbrl
17	232	compileGrouping	call site: 00232	compileRule
17	684	finalizeCharacter	call site: 00684	_lou_logMessage
13	286	compileRule	call site: 00286	addRule
13	489	compilePassOpcode	call site: 00489	passGetVariableNumber
10	469	verifyStringOrDots	call site: 00469	passGetDots
10	645	compileFile	call site: 00645	_lou_logMessage
9	583	compileRule	call site: 00583	addRule
9	880	translateString	call site: 00880	doCompTrans
8	550	compilePassOpcode	call site: 00550	passGetVariableNumber

Runtime coverage analysis

Covered functions

185

Functions that are reachable but not covered

55

Reachable functions

234

Percentage of reachable functions covered

76.5%

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	6
/src/liblouis/liblouis/compileTranslationTable.c	96
/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	58	0	333	256
_lou_defaultTableResolver	/src/liblouis/liblouis/compileTranslationTable.c	2	['N/A', 'N/A']	5	0	218	36	12	20	0	91	41

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

Functions statically reachable by fuzzers

259 / 295

Cyclomatic complexity statically reachable by fuzzers

3028 / 3215

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', 'parseChars', 'addForwardRuleWithSingleChar', 'compileRule', 'getAChar', 'getRuleDotsPattern', 'compileFile', 'rpl_free', 'getLogLevelFromEnvironment']

/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=['compileRule', 'compileGrouping', 'finalizeCharacter', '_lou_backTranslate', 'compileFile', 'handleMultind', 'getOpcode', 'lou_freeTableFiles']

/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', 'for_selectRule', 'compileGrouping', 'finalizeCharacter', 'compilePassOpcode', 'verifyStringOrDots', '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
resolveSubtable	67	23	34.32%	['fuzz_backtranslate', 'fuzz_translate_generic', 'table_fuzzer']
getLogLevelFromEnvironment	35	5	14.28%	['fuzz_backtranslate', 'fuzz_translate_generic', 'table_fuzzer']
finalizeCharacter	103	30	29.12%	['fuzz_backtranslate', 'fuzz_translate_generic']
handleMultind	49	13	26.53%	['fuzz_backtranslate']
swapTest	49	21	42.85%	['fuzz_translate_generic']
swapReplace	44	20	45.45%	['fuzz_translate_generic']
resolveEmphasisResets	122	56	45.90%	['fuzz_translate_generic']
for_selectRule	299	142	47.49%	['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/metadata.c	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']
/src/liblouis/liblouis/commonTranslationFunctions.c	['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']
/usr/local/bin/../include/c++/v1/stdexcept	[]	[]
/src/liblouis/tests/fuzzing/table_fuzzer.cc	['table_fuzzer']	['table_fuzzer']
/src/liblouis/liblouis/compileTranslationTable.c	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']
/src/liblouis/liblouis/./internal.h	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']	[]
/src/liblouis/liblouis/lou_backTranslateString.c	['fuzz_backtranslate']	['fuzz_backtranslate']
/src/liblouis/liblouis/lou_translateString.c	['fuzz_translate_generic']	['fuzz_translate_generic']
/src/liblouis/tests/fuzzing/fuzz_translate_generic.c	['fuzz_translate_generic']	['fuzz_translate_generic']
/src/liblouis/liblouis/pattern.c	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']	['fuzz_backtranslate', 'fuzz_translate_generic']
/src/liblouis/liblouis/logging.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/liblouis/utils.c	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']	['table_fuzzer', 'fuzz_backtranslate', 'fuzz_translate_generic']

Directories in report

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