diff options
Diffstat (limited to 'docs/env_variables.md')
| -rw-r--r-- | docs/env_variables.md | 58 |
1 files changed, 53 insertions, 5 deletions
diff --git a/docs/env_variables.md b/docs/env_variables.md index b1f23159..b3519107 100644 --- a/docs/env_variables.md +++ b/docs/env_variables.md @@ -135,6 +135,12 @@ subset of the settings discussed in section 1, with the exception of: - `TMPDIR` and `AFL_KEEP_ASSEMBLY`, since no temporary assembly files are created. + - LLVM modes compiling C++ will normally set rpath in the binary if LLVM is + not in a usual location (/usr or /lib). Setting `AFL_LLVM_NO_RPATH=1` + disables this behaviour in case it isn't desired. For example, the compiling + toolchain might be in a custom location, but the target machine has LLVM + runtime libs in the search path. + Then there are a few specific features that are only available in instrumentation mode: @@ -190,6 +196,19 @@ in the specified file. For more information, see [instrumentation/README.instrument_list.md](../instrumentation/README.instrument_list.md). +#### INJECTIONS + +This feature is able to find simple injection vulnerabilities in insecure +calls to mysql/mariadb/nosql/postgresql/ldap and XSS in libxml2. + + - Setting `AFL_LLVM_INJECTIONS_ALL` will enable all injection hooking + + - Setting `AFL_LLVM_INJECTIONS_SQL` will enable SQL injection hooking + + - Setting `AFL_LLVM_INJECTIONS_LDAP` will enable LDAP injection hooking + + - Setting `AFL_LLVM_INJECTIONS_XSS` will enable XSS injection hooking + #### LAF-INTEL This great feature will split compares into series of single byte comparisons to @@ -229,6 +248,9 @@ use (which only ever the author of this LTO implementation will use). These are used if several separated instrumentations are performed which are then later combined. + - `AFL_LLVM_LTO_CALLER` activates collision free CALLER instrumentation + - `AFL_LLVM_LTO_CALLER` sets the maximum mumber of single block functions + to dig deeper into a real function. Default 0. - `AFL_LLVM_DOCUMENT_IDS=file` will document to a file which edge ID was given to which function. This helps to identify functions with variable bytes or which functions were touched by an input. @@ -327,6 +349,9 @@ checks or alter some of the more exotic semantics of the tool: (`-i in`). This is an important feature to set when resuming a fuzzing session. + - `AFL_IGNORE_SEED_PROBLEMS` will skip over crashes and timeouts in the seeds + instead of exiting. + - Setting `AFL_CRASH_EXITCODE` sets the exit code AFL++ treats as crash. For example, if `AFL_CRASH_EXITCODE='-1'` is set, each input resulting in a `-1` return code (i.e. `exit(-1)` got called), will be treated as if a crash had @@ -356,6 +381,9 @@ checks or alter some of the more exotic semantics of the tool: - Setting `AFL_DISABLE_TRIM` tells afl-fuzz not to trim test cases. This is usually a bad idea! + - Setting `AFL_DISABLE_REDUNDANT` disables any queue items that are redundant. + This can be useful with huge queues. + - Setting `AFL_KEEP_TIMEOUTS` will keep longer running inputs if they reach new coverage @@ -365,6 +393,9 @@ checks or alter some of the more exotic semantics of the tool: - `AFL_EXIT_ON_SEED_ISSUES` will restore the vanilla afl-fuzz behavior which does not allow crashes or timeout seeds in the initial -i corpus. + - `AFL_CRASHING_SEEDS_AS_NEW_CRASH` will treat crashing seeds as new crash. these + crashes will be written to crashes folder as op:dry_run, and orig:<seed_file_name>. + - `AFL_EXIT_ON_TIME` causes afl-fuzz to terminate if no new paths were found within a specified period of time (in seconds). May be convenient for some types of automated jobs. @@ -409,10 +440,15 @@ checks or alter some of the more exotic semantics of the tool: set `AFL_IGNORE_PROBLEMS`. If you additionally want to also ignore coverage from late loaded libraries, you can set `AFL_IGNORE_PROBLEMS_COVERAGE`. - - When running in the `-M` or `-S` mode, setting `AFL_IMPORT_FIRST` causes the - fuzzer to import test cases from other instances before doing anything else. - This makes the "own finds" counter in the UI more accurate. Beyond counter - aesthetics, not much else should change. + - When running with multiple afl-fuzz or with `-F`, setting `AFL_IMPORT_FIRST` + causes the fuzzer to import test cases from other instances before doing + anything else. This makes the "own finds" counter in the UI more accurate. + + - When running with multiple afl-fuzz or with `-F`, setting `AFL_FINAL_SYNC` + will cause the fuzzer to perform a final import of test cases when + terminating. This is beneficial for `-M` main fuzzers to ensure it has all + unique test cases and hence you only need to `afl-cmin` this single + queue. - Setting `AFL_INPUT_LEN_MIN` and `AFL_INPUT_LEN_MAX` are an alternative to the afl-fuzz -g/-G command line option to control the minimum/maximum @@ -514,6 +550,9 @@ checks or alter some of the more exotic semantics of the tool: use a custom afl-qemu-trace or if you need to modify the afl-qemu-trace arguments. + - `AFL_SHA1_FILENAMES` causes AFL++ to generate files named by the SHA1 hash + of their contents, rather than use the standard `id:000000,...` names. + - `AFL_SHUFFLE_QUEUE` randomly reorders the input queue on startup. Requested by some users for unorthodox parallelized fuzzing setups, but not advisable otherwise. @@ -585,7 +624,8 @@ checks or alter some of the more exotic semantics of the tool: Note that this is not a compile time option but a runtime option :-) - Set `AFL_PIZZA_MODE` to 1 to enable the April 1st stats menu, set to -1 - to disable although it is 1st of April. + to disable although it is 1st of April. 0 is the default and means enable + on the 1st of April automatically. - If you need a specific interval to update fuzzer_stats file, you can set `AFL_FUZZER_STATS_UPDATE_INTERVAL` to the interval in seconds you'd @@ -619,6 +659,14 @@ The QEMU wrapper used to instrument binary-only code supports several settings: - Setting `AFL_INST_LIBS` causes the translator to also instrument the code inside any dynamically linked libraries (notably including glibc). + - You can use `AFL_QEMU_INST_RANGES=0xaaaa-0xbbbb,0xcccc-0xdddd` to just + instrument specific memory locations, e.g. a specific library. + Excluding ranges takes priority over any included ranges or `AFL_INST_LIBS`. + + - You can use `AFL_QEMU_EXCLUDE_RANGES=0xaaaa-0xbbbb,0xcccc-0xdddd` to **NOT** + instrument specific memory locations, e.g. a specific library. + Excluding ranges takes priority over any included ranges or `AFL_INST_LIBS`. + - It is possible to set `AFL_INST_RATIO` to skip the instrumentation on some of the basic blocks, which can be useful when dealing with very complex binaries. |