diff options
Diffstat (limited to 'src/afl-forkserver.c')
| -rw-r--r-- | src/afl-forkserver.c | 273 |
1 files changed, 238 insertions, 35 deletions
diff --git a/src/afl-forkserver.c b/src/afl-forkserver.c index 5aa4c2ff..7322f1ad 100644 --- a/src/afl-forkserver.c +++ b/src/afl-forkserver.c @@ -49,6 +49,134 @@ #include <sys/select.h> #include <sys/stat.h> +#ifdef __linux__ + #include <dlfcn.h> + +/* function to load nyx_helper function from libnyx.so */ + +nyx_plugin_handler_t *afl_load_libnyx_plugin(u8 *libnyx_binary) { + + void *handle; + nyx_plugin_handler_t *plugin = calloc(1, sizeof(nyx_plugin_handler_t)); + + ACTF("Trying to load libnyx.so plugin..."); + handle = dlopen((char *)libnyx_binary, RTLD_NOW); + if (!handle) { goto fail; } + + plugin->nyx_config_load = dlsym(handle, "nyx_config_load"); + if (plugin->nyx_config_load == NULL) { goto fail; } + + plugin->nyx_config_set_workdir_path = + dlsym(handle, "nyx_config_set_workdir_path"); + if (plugin->nyx_config_set_workdir_path == NULL) { goto fail; } + + plugin->nyx_config_set_input_buffer_size = + dlsym(handle, "nyx_config_set_input_buffer_size"); + if (plugin->nyx_config_set_input_buffer_size == NULL) { goto fail; } + + plugin->nyx_config_set_input_buffer_write_protection = + dlsym(handle, "nyx_config_set_input_buffer_write_protection"); + if (plugin->nyx_config_set_input_buffer_write_protection == NULL) { + + goto fail; + + } + + plugin->nyx_config_set_hprintf_fd = + dlsym(handle, "nyx_config_set_hprintf_fd"); + if (plugin->nyx_config_set_hprintf_fd == NULL) { goto fail; } + + plugin->nyx_config_set_process_role = + dlsym(handle, "nyx_config_set_process_role"); + if (plugin->nyx_config_set_process_role == NULL) { goto fail; } + + plugin->nyx_config_set_reuse_snapshot_path = + dlsym(handle, "nyx_config_set_reuse_snapshot_path"); + if (plugin->nyx_config_set_reuse_snapshot_path == NULL) { goto fail; } + + plugin->nyx_new = dlsym(handle, "nyx_new"); + if (plugin->nyx_new == NULL) { goto fail; } + + plugin->nyx_shutdown = dlsym(handle, "nyx_shutdown"); + if (plugin->nyx_shutdown == NULL) { goto fail; } + + plugin->nyx_option_set_reload_mode = + dlsym(handle, "nyx_option_set_reload_mode"); + if (plugin->nyx_option_set_reload_mode == NULL) { goto fail; } + + plugin->nyx_option_set_timeout = dlsym(handle, "nyx_option_set_timeout"); + if (plugin->nyx_option_set_timeout == NULL) { goto fail; } + + plugin->nyx_option_apply = dlsym(handle, "nyx_option_apply"); + if (plugin->nyx_option_apply == NULL) { goto fail; } + + plugin->nyx_set_afl_input = dlsym(handle, "nyx_set_afl_input"); + if (plugin->nyx_set_afl_input == NULL) { goto fail; } + + plugin->nyx_exec = dlsym(handle, "nyx_exec"); + if (plugin->nyx_exec == NULL) { goto fail; } + + plugin->nyx_get_bitmap_buffer = dlsym(handle, "nyx_get_bitmap_buffer"); + if (plugin->nyx_get_bitmap_buffer == NULL) { goto fail; } + + plugin->nyx_get_bitmap_buffer_size = + dlsym(handle, "nyx_get_bitmap_buffer_size"); + if (plugin->nyx_get_bitmap_buffer_size == NULL) { goto fail; } + + plugin->nyx_get_aux_string = dlsym(handle, "nyx_get_aux_string"); + if (plugin->nyx_get_aux_string == NULL) { goto fail; } + + plugin->nyx_remove_work_dir = dlsym(handle, "nyx_remove_work_dir"); + if (plugin->nyx_remove_work_dir == NULL) { goto fail; } + + OKF("libnyx plugin is ready!"); + return plugin; + +fail: + + FATAL("failed to load libnyx: %s\n", dlerror()); + ck_free(plugin); + return NULL; + +} + +void afl_nyx_runner_kill(afl_forkserver_t *fsrv) { + + if (fsrv->nyx_mode) { + + if (fsrv->nyx_aux_string) { ck_free(fsrv->nyx_aux_string); } + + /* check if we actually got a valid nyx runner */ + if (fsrv->nyx_runner) { + + fsrv->nyx_handlers->nyx_shutdown(fsrv->nyx_runner); + + } + + /* if we have use a tmp work dir we need to remove it */ + if (fsrv->nyx_use_tmp_workdir && fsrv->nyx_tmp_workdir_path) { + + remove_nyx_tmp_workdir(fsrv, fsrv->nyx_tmp_workdir_path); + + } + + } + +} + + /* Wrapper for FATAL() that kills the nyx runner (and removes all created tmp + * files) before exiting. Used before "afl_fsrv_killall()" is registered as + * an atexit() handler. */ + #define NYX_PRE_FATAL(fsrv, x...) \ + do { \ + \ + afl_nyx_runner_kill(fsrv); \ + FATAL(x); \ + \ + } while (0) + +#endif + /** * The correct fds for reading and writing pipes */ @@ -84,6 +212,8 @@ void afl_fsrv_init(afl_forkserver_t *fsrv) { fsrv->nyx_runner = NULL; fsrv->nyx_id = 0xFFFFFFFF; fsrv->nyx_bind_cpu_id = 0xFFFFFFFF; + fsrv->nyx_use_tmp_workdir = false; + fsrv->nyx_tmp_workdir_path = NULL; #endif // this structure needs default so we initialize it if this was not done @@ -359,7 +489,7 @@ static void report_error_and_exit(int error) { break; case FS_ERROR_OLD_CMPLOG: FATAL( - "the -c cmplog target was instrumented with an too old afl++ " + "the -c cmplog target was instrumented with an too old AFL++ " "version, you need to recompile it."); break; case FS_ERROR_OLD_CMPLOG_QEMU: @@ -397,40 +527,119 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, if (!be_quiet) { ACTF("Spinning up the NYX backend..."); } - if (fsrv->out_dir_path == NULL) { FATAL("Nyx workdir path not found..."); } + if (fsrv->nyx_use_tmp_workdir) { + + fsrv->nyx_tmp_workdir_path = create_nyx_tmp_workdir(); + fsrv->out_dir_path = fsrv->nyx_tmp_workdir_path; + + } else { + + if (fsrv->out_dir_path == NULL) { + + NYX_PRE_FATAL(fsrv, "Nyx workdir path not found..."); + + } + + } + + /* libnyx expects an absolute path */ + char *outdir_path_absolute = realpath(fsrv->out_dir_path, NULL); + if (outdir_path_absolute == NULL) { - char *x = alloc_printf("%s/workdir", fsrv->out_dir_path); + NYX_PRE_FATAL(fsrv, "Nyx workdir path cannot be resolved ..."); - if (fsrv->nyx_id == 0xFFFFFFFF) { FATAL("Nyx ID is not set..."); } + } + + char *workdir_path = alloc_printf("%s/workdir", outdir_path_absolute); + + if (fsrv->nyx_id == 0xFFFFFFFF) { + + NYX_PRE_FATAL(fsrv, "Nyx ID is not set..."); + + } if (fsrv->nyx_bind_cpu_id == 0xFFFFFFFF) { - FATAL("Nyx CPU ID is not set..."); + NYX_PRE_FATAL(fsrv, "Nyx CPU ID is not set..."); } + void *nyx_config = fsrv->nyx_handlers->nyx_config_load(fsrv->target_path); + + fsrv->nyx_handlers->nyx_config_set_workdir_path(nyx_config, workdir_path); + fsrv->nyx_handlers->nyx_config_set_input_buffer_size(nyx_config, MAX_FILE); + fsrv->nyx_handlers->nyx_config_set_input_buffer_write_protection(nyx_config, + true); + if (fsrv->nyx_standalone) { - fsrv->nyx_runner = fsrv->nyx_handlers->nyx_new( - fsrv->target_path, x, fsrv->nyx_bind_cpu_id, MAX_FILE, true); + fsrv->nyx_handlers->nyx_config_set_process_role(nyx_config, StandAlone); } else { if (fsrv->nyx_parent) { - fsrv->nyx_runner = fsrv->nyx_handlers->nyx_new_parent( - fsrv->target_path, x, fsrv->nyx_bind_cpu_id, MAX_FILE, true); + fsrv->nyx_handlers->nyx_config_set_process_role(nyx_config, Parent); } else { - fsrv->nyx_runner = fsrv->nyx_handlers->nyx_new_child( - fsrv->target_path, x, fsrv->nyx_bind_cpu_id, fsrv->nyx_id); + fsrv->nyx_handlers->nyx_config_set_process_role(nyx_config, Child); + + } + + } + + if (getenv("NYX_REUSE_SNAPSHOT") != NULL) { + + if (access(getenv("NYX_REUSE_SNAPSHOT"), F_OK) == -1) { + + NYX_PRE_FATAL(fsrv, "NYX_REUSE_SNAPSHOT path does not exist"); + + } + + /* stupid sanity check to avoid passing an empty or invalid snapshot + * directory */ + char *snapshot_file_path = + alloc_printf("%s/global.state", getenv("NYX_REUSE_SNAPSHOT")); + if (access(snapshot_file_path, R_OK) == -1) { + + NYX_PRE_FATAL( + fsrv, + "NYX_REUSE_SNAPSHOT path does not contain a valid Nyx snapshot"); + + } + + ck_free(snapshot_file_path); + + /* another sanity check to avoid passing a snapshot directory that is + * located in the current workdir (the workdir will be wiped by libnyx on + * startup) */ + char *workdir_snapshot_path = + alloc_printf("%s/workdir/snapshot", outdir_path_absolute); + char *reuse_snapshot_path_real = + realpath(getenv("NYX_REUSE_SNAPSHOT"), NULL); + + if (strcmp(workdir_snapshot_path, reuse_snapshot_path_real) == 0) { + + NYX_PRE_FATAL(fsrv, + "NYX_REUSE_SNAPSHOT path is located in current workdir " + "(use another output directory)"); } + ck_free(reuse_snapshot_path_real); + ck_free(workdir_snapshot_path); + + fsrv->nyx_handlers->nyx_config_set_reuse_snapshot_path( + nyx_config, getenv("NYX_REUSE_SNAPSHOT")); + } - ck_free(x); + fsrv->nyx_runner = + fsrv->nyx_handlers->nyx_new(nyx_config, fsrv->nyx_bind_cpu_id); + + ck_free(workdir_path); + ck_free(outdir_path_absolute); if (fsrv->nyx_runner == NULL) { FATAL("Something went wrong ..."); } @@ -458,15 +667,13 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, switch (fsrv->nyx_handlers->nyx_exec(fsrv->nyx_runner)) { case Abort: - fsrv->nyx_handlers->nyx_shutdown(fsrv->nyx_runner); - FATAL("Error: Nyx abort occured..."); + NYX_PRE_FATAL(fsrv, "Error: Nyx abort occured..."); break; case IoError: - FATAL("Error: QEMU-Nyx has died..."); + NYX_PRE_FATAL(fsrv, "Error: QEMU-Nyx has died..."); break; case Error: - fsrv->nyx_handlers->nyx_shutdown(fsrv->nyx_runner); - FATAL("Error: Nyx runtime error has occured..."); + NYX_PRE_FATAL(fsrv, "Error: Nyx runtime error has occured..."); break; default: break; @@ -476,7 +683,8 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, /* autodict in Nyx mode */ if (!ignore_autodict) { - x = alloc_printf("%s/workdir/dump/afl_autodict.txt", fsrv->out_dir_path); + char *x = + alloc_printf("%s/workdir/dump/afl_autodict.txt", fsrv->out_dir_path); int nyx_autodict_fd = open(x, O_RDONLY); ck_free(x); @@ -489,8 +697,9 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, u8 *dict = ck_alloc(f_len); if (dict == NULL) { - FATAL("Could not allocate %u bytes of autodictionary memory", - f_len); + NYX_PRE_FATAL( + fsrv, "Could not allocate %u bytes of autodictionary memory", + f_len); } @@ -507,7 +716,8 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, } else { - FATAL( + NYX_PRE_FATAL( + fsrv, "Reading autodictionary fail at position %u with %u bytes " "left.", offset, len); @@ -777,7 +987,7 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, if ((status & FS_OPT_ENABLED) == FS_OPT_ENABLED) { - // workaround for recent afl++ versions + // workaround for recent AFL++ versions if ((status & FS_OPT_OLD_AFLPP_WORKAROUND) == FS_OPT_OLD_AFLPP_WORKAROUND) status = (status & 0xf0ffffff); @@ -849,7 +1059,7 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, FATAL( "Target's coverage map size of %u is larger than the one this " - "afl++ is set with (%u). Either set AFL_MAP_SIZE=%u and restart " + "AFL++ is set with (%u). Either set AFL_MAP_SIZE=%u and restart " " afl-fuzz, or change MAP_SIZE_POW2 in config.h and recompile " "afl-fuzz", tmp_map_size, fsrv->map_size, tmp_map_size); @@ -1016,7 +1226,7 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, " - Less likely, there is a horrible bug in the fuzzer. If other " "options\n" - " fail, poke <afl-users@googlegroups.com> for troubleshooting " + " fail, poke the Awesome Fuzzing Discord for troubleshooting " "tips.\n"); } else { @@ -1061,7 +1271,7 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, " - Less likely, there is a horrible bug in the fuzzer. If other " "options\n" - " fail, poke <afl-users@googlegroups.com> for troubleshooting " + " fail, poke the Awesome Fuzzing Discord for troubleshooting " "tips.\n", stringify_mem_size(val_buf, sizeof(val_buf), fsrv->mem_limit << 20), fsrv->mem_limit - 1); @@ -1111,7 +1321,7 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, " Retry with setting AFL_MAP_SIZE=10000000.\n\n" "Otherwise there is a horrible bug in the fuzzer.\n" - "Poke <afl-users@googlegroups.com> for troubleshooting tips.\n"); + "Poke the Awesome Fuzzing Discord for troubleshooting tips.\n"); } else { @@ -1160,7 +1370,7 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, " - Less likely, there is a horrible bug in the fuzzer. If other " "options\n" - " fail, poke <afl-users@googlegroups.com> for troubleshooting " + " fail, poke the Awesome Fuzzing Discord for troubleshooting " "tips.\n", getenv(DEFER_ENV_VAR) ? " - You are using deferred forkserver, but __AFL_INIT() is " @@ -1194,13 +1404,7 @@ void afl_fsrv_kill(afl_forkserver_t *fsrv) { fsrv->child_pid = -1; #ifdef __linux__ - if (fsrv->nyx_mode) { - - free(fsrv->nyx_aux_string); - fsrv->nyx_handlers->nyx_shutdown(fsrv->nyx_runner); - - } - + afl_nyx_runner_kill(fsrv); #endif } @@ -1377,7 +1581,6 @@ afl_fsrv_run_target(afl_forkserver_t *fsrv, u32 timeout, FATAL("FixMe: Nyx InvalidWriteToPayload handler is missing"); break; case Abort: - fsrv->nyx_handlers->nyx_shutdown(fsrv->nyx_runner); FATAL("Error: Nyx abort occured..."); case IoError: if (*stop_soon_p) { |