/* american fuzzy lop++ - network proxy server ------------------------------------------- Originally written by Michal Zalewski Forkserver design by Jann Horn Now maintained by Marc Heuse , Heiko Eißfeldt and Andrea Fioraldi and Dominik Maier Copyright 2016, 2017 Google Inc. All rights reserved. Copyright 2019-2024 AFLplusplus Project. All rights reserved. Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at: http://www.apache.org/licenses/LICENSE-2.0 */ #define AFL_MAIN #include "config.h" #include "types.h" #include "debug.h" #include "alloc-inl.h" #include "hash.h" #include "forkserver.h" #include "sharedmem.h" #include "common.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifndef USEMMAP #include #endif #include #include #ifdef USE_DEFLATE #include struct libdeflate_compressor *compressor; struct libdeflate_decompressor *decompressor; #endif static u8 *in_file, /* Minimizer input test case */ *out_file; static u8 *in_data; /* Input data for trimming */ static u8 *buf2; static s32 in_len; static s32 buf2_len; static u32 map_size = MAP_SIZE; static volatile u8 stop_soon; /* Ctrl-C pressed? */ /* See if any bytes are set in the bitmap. */ static inline u8 anything_set(afl_forkserver_t *fsrv) { u32 *ptr = (u32 *)fsrv->trace_bits; u32 i = (map_size >> 2); while (i--) { if (*(ptr++)) { return 1; } } return 0; } static void at_exit_handler(void) { afl_fsrv_killall(); } /* Write output file. */ static s32 write_to_file(u8 *path, u8 *mem, u32 len) { s32 ret; unlink(path); /* Ignore errors */ ret = open(path, O_RDWR | O_CREAT | O_EXCL, 0600); if (ret < 0) { PFATAL("Unable to create '%s'", path); } ck_write(ret, mem, len, path); lseek(ret, 0, SEEK_SET); return ret; } /* Execute target application. Returns 0 if the changes are a dud, or 1 if they should be kept. */ static u8 run_target(afl_forkserver_t *fsrv, char **argv, u8 *mem, u32 len, u8 first_run) { afl_fsrv_write_to_testcase(fsrv, mem, len); fsrv_run_result_t ret = afl_fsrv_run_target(fsrv, fsrv->exec_tmout, &stop_soon); if (ret == FSRV_RUN_ERROR) { FATAL("Couldn't run child"); } if (stop_soon) { SAYF(cRST cLRD "\n+++ aborted by user +++\n" cRST); exit(1); } return ret; } /* Handle Ctrl-C and the like. */ static void handle_stop_sig(int sig) { stop_soon = 1; afl_fsrv_killall(); } /* Do basic preparations - persistent fds, filenames, etc. */ static void set_up_environment(afl_forkserver_t *fsrv) { u8 *x; fsrv->dev_null_fd = open("/dev/null", O_RDWR); if (fsrv->dev_null_fd < 0) { PFATAL("Unable to open /dev/null"); } if (!out_file) { u8 *use_dir = "."; if (access(use_dir, R_OK | W_OK | X_OK)) { use_dir = get_afl_env("TMPDIR"); if (!use_dir) { use_dir = "/tmp"; } } out_file = alloc_printf("%s/.afl-input-temp-%u", use_dir, getpid()); fsrv->out_file = out_file; } unlink(out_file); fsrv->out_fd = open(out_file, O_RDWR | O_CREAT | O_EXCL, 0600); if (fsrv->out_fd < 0) { PFATAL("Unable to create '%s'", out_file); } /* Set sane defaults... */ x = get_afl_env("ASAN_OPTIONS"); if (x) { if (!strstr(x, "abort_on_error=1")) { FATAL("Custom ASAN_OPTIONS set without abort_on_error=1 - please fix!"); } if (!getenv("AFL_DEBUG") && !strstr(x, "symbolize=0")) { FATAL("Custom ASAN_OPTIONS set without symbolize=0 - please fix!"); } } x = get_afl_env("MSAN_OPTIONS"); if (x) { if (!strstr(x, "exit_code=" STRINGIFY(MSAN_ERROR))) { FATAL("Custom MSAN_OPTIONS set without exit_code=" STRINGIFY( MSAN_ERROR) " - please fix!"); } if (!getenv("AFL_DEBUG") && !strstr(x, "symbolize=0")) { FATAL("Custom MSAN_OPTIONS set without symbolize=0 - please fix!"); } } set_sanitizer_defaults(); if (get_afl_env("AFL_PRELOAD")) { if (fsrv->qemu_mode) { /* afl-qemu-trace takes care of converting AFL_PRELOAD. */ } else { setenv("LD_PRELOAD", getenv("AFL_PRELOAD"), 1); setenv("DYLD_INSERT_LIBRARIES", getenv("AFL_PRELOAD"), 1); } } } /* Setup signal handlers, duh. */ static void setup_signal_handlers(void) { struct sigaction sa; sa.sa_handler = NULL; sa.sa_flags = SA_RESTART; sa.sa_sigaction = NULL; sigemptyset(&sa.sa_mask); /* Various ways of saying "stop". */ sa.sa_handler = handle_stop_sig; sigaction(SIGHUP, &sa, NULL); sigaction(SIGINT, &sa, NULL); sigaction(SIGTERM, &sa, NULL); } /* Display usage hints. */ static void usage(u8 *argv0) { SAYF( "\n%s [ options ] -- /path/to/target_app [ ... ]\n\n" "Required parameters:\n" " -i port - the port to listen for the client to connect to\n\n" "Execution control settings:\n" " -f file - input file read by the tested program (stdin)\n" " -t msec - timeout for each run (%d ms)\n" " -m megs - memory limit for child process (%d MB)\n" " -Q - use binary-only instrumentation (QEMU mode)\n" " -U - use unicorn-based instrumentation (Unicorn mode)\n" " -W - use qemu-based instrumentation with Wine (Wine " "mode)\n\n" "Environment variables used:\n" "TMPDIR: directory to use for temporary input files\n" "ASAN_OPTIONS: custom settings for ASAN\n" " (must contain abort_on_error=1 and symbolize=0)\n" "MSAN_OPTIONS: custom settings for MSAN\n" " (must contain exitcode="STRINGIFY(MSAN_ERROR)" and symbolize=0)\n" "AFL_MAP_SIZE: the shared memory size for that target. must be >= the size\n" " the target was compiled for\n" "AFL_PRELOAD: LD_PRELOAD / DYLD_INSERT_LIBRARIES settings for target\n" , argv0, EXEC_TIMEOUT, MEM_LIMIT); exit(1); } int recv_testcase(int s, void **buf) { u32 size; s32 ret; size_t received; received = 0; while (received < 4 && (ret = recv(s, &size + received, 4 - received, 0)) > 0) received += ret; if (received != 4) FATAL("did not receive size information"); if (size == 0) FATAL("did not receive valid size information"); // fprintf(stderr, "received size information of %d\n", size); if ((size & 0xff000000) != 0xff000000) { *buf = afl_realloc(buf, size); if (unlikely(!*buf)) { PFATAL("Alloc"); } received = 0; // fprintf(stderr, "unCOMPRESS (%u)\n", size); while (received < size && (ret = recv(s, ((char *)*buf) + received, size - received, 0)) > 0) received += ret; } else { #ifdef USE_DEFLATE u32 clen; size -= 0xff000000; *buf = afl_realloc(buf, size); if (unlikely(!*buf)) { PFATAL("Alloc"); } received = 0; while (received < 4 && (ret = recv(s, &clen + received, 4 - received, 0)) > 0) received += ret; if (received != 4) FATAL("did not receive clen1 information"); // fprintf(stderr, "received clen information of %d\n", clen); if (clen < 1) FATAL("did not receive valid compressed len information: %u", clen); buf2 = afl_realloc((void **)&buf2, clen); buf2_len = clen; if (unlikely(!buf2)) { PFATAL("Alloc"); } received = 0; while (received < clen && (ret = recv(s, buf2 + received, clen - received, 0)) > 0) received += ret; if (received != clen) FATAL("did not receive compressed information"); if (libdeflate_deflate_decompress(decompressor, buf2, clen, (char *)*buf, size, &received) != LIBDEFLATE_SUCCESS) FATAL("decompression failed"); // fprintf(stderr, "DECOMPRESS (%u->%u):\n", clen, received); // for (u32 i = 0; i < clen; i++) fprintf(stderr, "%02x", buf2[i]); // fprintf(stderr, "\n"); // for (u32 i = 0; i < received; i++) fprintf(stderr, "%02x", // ((u8*)(*buf))[i]); fprintf(stderr, "\n"); #else FATAL("Received compressed data but not compiled with compression support"); #endif } // fprintf(stderr, "receiving testcase %p %p max %u\n", buf, *buf, *max_len); if (received != size) FATAL("did not receive testcase data %lu != %u, %d", received, size, ret); // fprintf(stderr, "received testcase\n"); return size; } /* Main entry point */ int main(int argc, char **argv_orig, char **envp) { s32 opt, s, sock, on = 1, port = -1; u8 mem_limit_given = 0, timeout_given = 0, unicorn_mode = 0, use_wine = 0; char **use_argv; struct sockaddr_in6 serveraddr, clientaddr; int addrlen = sizeof(clientaddr); char str[INET6_ADDRSTRLEN]; char **argv = argv_cpy_dup(argc, argv_orig); u8 *send_buf; #ifdef USE_DEFLATE u32 *lenptr; #endif afl_forkserver_t fsrv_var = {0}; afl_forkserver_t *fsrv = &fsrv_var; afl_fsrv_init(fsrv); map_size = get_map_size(); fsrv->map_size = map_size; if ((send_buf = malloc(map_size + 4)) == NULL) PFATAL("malloc"); while ((opt = getopt(argc, argv, "+i:f:m:t:QUWh")) > 0) { switch (opt) { case 'i': if (port > 0) { FATAL("Multiple -i options not supported"); } port = atoi(optarg); if (port < 1 || port > 65535) FATAL("invalid port definition, must be between 1-65535: %s", optarg); break; case 'f': if (out_file) { FATAL("Multiple -f options not supported"); } fsrv->use_stdin = 0; out_file = optarg; break; case 'm': { u8 suffix = 'M'; if (mem_limit_given) { FATAL("Multiple -m options not supported"); } mem_limit_given = 1; if (!optarg) { FATAL("Wrong usage of -m"); } if (!strcmp(optarg, "none")) { fsrv->mem_limit = 0; break; } if (sscanf(optarg, "%llu%c", &fsrv->mem_limit, &suffix) < 1 || optarg[0] == '-') { FATAL("Bad syntax used for -m"); } switch (suffix) { case 'T': fsrv->mem_limit *= 1024 * 1024; break; case 'G': fsrv->mem_limit *= 1024; break; case 'k': fsrv->mem_limit /= 1024; break; case 'M': break; default: FATAL("Unsupported suffix or bad syntax for -m"); } if (fsrv->mem_limit < 5) { FATAL("Dangerously low value of -m"); } if (sizeof(rlim_t) == 4 && fsrv->mem_limit > 2000) { FATAL("Value of -m out of range on 32-bit systems"); } } break; case 't': if (timeout_given) { FATAL("Multiple -t options not supported"); } timeout_given = 1; if (!optarg) { FATAL("Wrong usage of -t"); } fsrv->exec_tmout = atoi(optarg); if (fsrv->exec_tmout < 10 || optarg[0] == '-') { FATAL("Dangerously low value of -t"); } break; case 'Q': if (fsrv->qemu_mode) { FATAL("Multiple -Q options not supported"); } if (!mem_limit_given) { fsrv->mem_limit = MEM_LIMIT_QEMU; } fsrv->qemu_mode = 1; break; case 'U': if (unicorn_mode) { FATAL("Multiple -Q options not supported"); } if (!mem_limit_given) { fsrv->mem_limit = MEM_LIMIT_UNICORN; } unicorn_mode = 1; break; case 'W': /* Wine+QEMU mode */ if (use_wine) { FATAL("Multiple -W options not supported"); } fsrv->qemu_mode = 1; use_wine = 1; if (!mem_limit_given) { fsrv->mem_limit = 0; } break; case 'h': usage(argv[0]); return -1; break; default: usage(argv[0]); } } if (optind == argc || port < 1) { usage(argv[0]); } check_environment_vars(envp); sharedmem_t shm = {0}; fsrv->trace_bits = afl_shm_init(&shm, map_size, 0); in_data = afl_realloc((void **)&in_data, 65536); if (unlikely(!in_data)) { PFATAL("Alloc"); } atexit(at_exit_handler); setup_signal_handlers(); set_up_environment(fsrv); fsrv->target_path = find_binary(argv[optind]); detect_file_args(argv + optind, out_file, &fsrv->use_stdin); if (fsrv->qemu_mode) { if (use_wine) { use_argv = get_wine_argv(argv[0], &fsrv->target_path, argc - optind, argv + optind); } else { use_argv = get_qemu_argv(argv[0], &fsrv->target_path, argc - optind, argv + optind); } } else { use_argv = argv + optind; } if ((sock = socket(AF_INET6, SOCK_STREAM, 0)) < 0) PFATAL("socket() failed"); #ifdef SO_REUSEADDR if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (char *)&on, sizeof(on)) < 0) { WARNF("setsockopt(SO_REUSEADDR) failed"); } #endif #ifdef SO_PRIORITY int priority = 7; if (setsockopt(sock, SOL_SOCKET, SO_PRIORITY, &priority, sizeof(priority)) < 0) { priority = 6; if (setsockopt(sock, SOL_SOCKET, SO_PRIORITY, &priority, sizeof(priority)) < 0) WARNF("could not set priority on socket"); } #endif memset(&serveraddr, 0, sizeof(serveraddr)); serveraddr.sin6_family = AF_INET6; serveraddr.sin6_port = htons(port); serveraddr.sin6_addr = in6addr_any; if (bind(sock, (struct sockaddr *)&serveraddr, sizeof(serveraddr)) < 0) PFATAL("bind() failed"); if (listen(sock, 1) < 0) { PFATAL("listen() failed"); } afl_fsrv_start( fsrv, use_argv, &stop_soon, (get_afl_env("AFL_DEBUG_CHILD") || get_afl_env("AFL_DEBUG_CHILD_OUTPUT")) ? 1 : 0); #ifdef USE_DEFLATE compressor = libdeflate_alloc_compressor(1); decompressor = libdeflate_alloc_decompressor(); buf2 = afl_realloc((void **)&buf2, map_size + 16); buf2_len = map_size + 16; if (unlikely(!buf2)) { PFATAL("alloc"); } lenptr = (u32 *)(buf2 + 4); fprintf(stderr, "Compiled with compression support\n"); #endif fprintf(stderr, "Waiting for incoming connection from afl-network-client on port %d " "...\n", port); if ((s = accept(sock, NULL, NULL)) < 0) { PFATAL("accept() failed"); } fprintf(stderr, "Received connection, starting ...\n"); #ifdef SO_PRIORITY priority = 7; if (setsockopt(s, SOL_SOCKET, SO_PRIORITY, &priority, sizeof(priority)) < 0) { priority = 6; if (setsockopt(s, SOL_SOCKET, SO_PRIORITY, &priority, sizeof(priority)) < 0) WARNF("could not set priority on socket"); } #endif while ((in_len = recv_testcase(s, (void **)&in_data)) > 0) { // fprintf(stderr, "received %u\n", in_len); (void)run_target(fsrv, use_argv, in_data, in_len, 1); memcpy(send_buf + 4, fsrv->trace_bits, fsrv->map_size); #ifdef USE_DEFLATE memcpy(buf2, &fsrv->child_status, 4); *lenptr = (u32)libdeflate_deflate_compress( compressor, send_buf + 4, fsrv->map_size, buf2 + 8, buf2_len - 8); // fprintf(stderr, "COMPRESS (%u->%u): ", fsrv->map_size, *lenptr); // for (u32 i = 0; i < fsrv->map_size; i++) fprintf(stderr, "%02x", // fsrv->trace_bits[i]); fprintf(stderr, "\n"); if (send(s, buf2, *lenptr + 8, 0) != 8 + *lenptr) FATAL("could not send data"); #else memcpy(send_buf, &fsrv->child_status, 4); if (send(s, send_buf, fsrv->map_size + 4, 0) != 4 + fsrv->map_size) FATAL("could not send data"); #endif // fprintf(stderr, "sent result\n"); } unlink(out_file); if (out_file) { ck_free(out_file); } out_file = NULL; afl_shm_deinit(&shm); afl_fsrv_deinit(fsrv); if (fsrv->target_path) { ck_free(fsrv->target_path); } afl_free(in_data); #if USE_DEFLATE afl_free(buf2); libdeflate_free_compressor(compressor); libdeflate_free_decompressor(decompressor); #endif argv_cpy_free(argv); exit(0); }