/* american fuzzy lop++ - common routines -------------------------------------- Originally written by Michal Zalewski Now maintained by Marc Heuse , Heiko Eißfeldt and Andrea Fioraldi Copyright 2016, 2017 Google Inc. All rights reserved. Copyright 2019-2020 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 Gather some functions common to multiple executables - detect_file_args */ #include #include #include #include #include "debug.h" #include "alloc-inl.h" #include "envs.h" #include "common.h" /* Detect @@ in args. */ #ifndef __glibc__ #include #endif #include #include #include #include #include u8 be_quiet = 0; u8 *doc_path = ""; u8 last_intr = 0; void detect_file_args(char **argv, u8 *prog_in, bool *use_stdin) { u32 i = 0; u8 cwd[PATH_MAX]; if (getcwd(cwd, (size_t)sizeof(cwd)) == NULL) { PFATAL("getcwd() failed"); } /* we are working with libc-heap-allocated argvs. So do not mix them with * other allocation APIs like ck_alloc. That would disturb the free() calls. */ while (argv[i]) { u8 *aa_loc = strstr(argv[i], "@@"); if (aa_loc) { if (!prog_in) { FATAL("@@ syntax is not supported by this tool."); } *use_stdin = false; if (prog_in[0] != 0) { // not afl-showmap special case u8 *n_arg; /* Be sure that we're always using fully-qualified paths. */ *aa_loc = 0; /* Construct a replacement argv value. */ if (prog_in[0] == '/') { n_arg = alloc_printf("%s%s%s", argv[i], prog_in, aa_loc + 2); } else { n_arg = alloc_printf("%s%s/%s%s", argv[i], cwd, prog_in, aa_loc + 2); } ck_free(argv[i]); argv[i] = n_arg; } } i++; } /* argvs are automatically freed at exit. */ } /* duplicate the system argv so that we can edit (and free!) it later */ char **argv_cpy_dup(int argc, char **argv) { int i = 0; char **ret = ck_alloc((argc + 1) * sizeof(char *)); if (unlikely(!ret)) { FATAL("Amount of arguments specified is too high"); } for (i = 0; i < argc; i++) { ret[i] = ck_strdup(argv[i]); } ret[i] = NULL; return ret; } /* frees all args in the given argv, previously created by argv_cpy_dup */ void argv_cpy_free(char **argv) { u32 i = 0; while (argv[i]) { ck_free(argv[i]); argv[i] = NULL; i++; } ck_free(argv); } /* Rewrite argv for QEMU. */ char **get_qemu_argv(u8 *own_loc, u8 **target_path_p, int argc, char **argv) { if (!unlikely(own_loc)) { FATAL("BUG: param own_loc is NULL"); } u8 *tmp, *cp = NULL, *rsl, *own_copy; char **new_argv = ck_alloc(sizeof(char *) * (argc + 4)); if (unlikely(!new_argv)) { FATAL("Illegal amount of arguments specified"); } memcpy(&new_argv[3], &argv[1], (int)(sizeof(char *)) * (argc - 1)); new_argv[argc + 3] = NULL; new_argv[2] = *target_path_p; new_argv[1] = "--"; /* Now we need to actually find the QEMU binary to put in argv[0]. */ tmp = getenv("AFL_PATH"); if (tmp) { cp = alloc_printf("%s/afl-qemu-trace", tmp); if (access(cp, X_OK)) { FATAL("Unable to find '%s'", tmp); } *target_path_p = new_argv[0] = cp; return new_argv; } own_copy = ck_strdup(own_loc); rsl = strrchr(own_copy, '/'); if (rsl) { *rsl = 0; cp = alloc_printf("%s/afl-qemu-trace", own_copy); ck_free(own_copy); if (!access(cp, X_OK)) { *target_path_p = new_argv[0] = cp; return new_argv; } } else { ck_free(own_copy); } if (!access(BIN_PATH "/afl-qemu-trace", X_OK)) { if (cp) { ck_free(cp); } *target_path_p = new_argv[0] = ck_strdup(BIN_PATH "/afl-qemu-trace"); return new_argv; } SAYF("\n" cLRD "[-] " cRST "Oops, unable to find the 'afl-qemu-trace' binary. The binary must be " "built\n" " separately by following the instructions in " "qemu_mode/README.md. " "If you\n" " already have the binary installed, you may need to specify " "AFL_PATH in the\n" " environment.\n\n" " Of course, even without QEMU, afl-fuzz can still work with " "binaries that are\n" " instrumented at compile time with afl-gcc. It is also possible to " "use it as a\n" " traditional non-instrumented fuzzer by specifying '-n' in the " "command " "line.\n"); FATAL("Failed to locate 'afl-qemu-trace'."); } /* Rewrite argv for Wine+QEMU. */ char **get_wine_argv(u8 *own_loc, u8 **target_path_p, int argc, char **argv) { if (!unlikely(own_loc)) { FATAL("BUG: param own_loc is NULL"); } u8 *tmp, *cp = NULL, *rsl, *own_copy; char **new_argv = ck_alloc(sizeof(char *) * (argc + 3)); if (unlikely(!new_argv)) { FATAL("Illegal amount of arguments specified"); } memcpy(&new_argv[2], &argv[1], (int)(sizeof(char *)) * (argc - 1)); new_argv[argc + 2] = NULL; new_argv[1] = *target_path_p; /* Now we need to actually find the QEMU binary to put in argv[0]. */ tmp = getenv("AFL_PATH"); if (tmp) { cp = alloc_printf("%s/afl-qemu-trace", tmp); if (access(cp, X_OK)) { FATAL("Unable to find '%s'", tmp); } ck_free(cp); cp = alloc_printf("%s/afl-wine-trace", tmp); if (access(cp, X_OK)) { FATAL("Unable to find '%s'", tmp); } *target_path_p = new_argv[0] = cp; return new_argv; } own_copy = ck_strdup(own_loc); rsl = strrchr(own_copy, '/'); if (rsl) { *rsl = 0; cp = alloc_printf("%s/afl-qemu-trace", own_copy); if (cp && !access(cp, X_OK)) { ck_free(cp); cp = alloc_printf("%s/afl-wine-trace", own_copy); if (!access(cp, X_OK)) { *target_path_p = new_argv[0] = cp; return new_argv; } } ck_free(own_copy); } else { ck_free(own_copy); } u8 *ncp = BIN_PATH "/afl-qemu-trace"; if (!access(ncp, X_OK)) { ncp = BIN_PATH "/afl-wine-trace"; if (!access(ncp, X_OK)) { *target_path_p = new_argv[0] = ck_strdup(ncp); return new_argv; } } SAYF("\n" cLRD "[-] " cRST "Oops, unable to find the '%s' binary. The binary must be " "built\n" " separately by following the instructions in " "qemu_mode/README.md. " "If you\n" " already have the binary installed, you may need to specify " "AFL_PATH in the\n" " environment.\n\n" " Of course, even without QEMU, afl-fuzz can still work with " "binaries that are\n" " instrumented at compile time with afl-gcc. It is also possible to " "use it as a\n" " traditional non-instrumented fuzzer by specifying '-n' in the " "command " "line.\n", ncp); FATAL("Failed to locate '%s'.", ncp); } /* Find binary, used by analyze, showmap, tmin @returns the path, allocating the string */ u8 *find_binary(u8 *fname) { // TODO: Merge this function with check_binary of afl-fuzz-init.c u8 *env_path = NULL; u8 *target_path = NULL; struct stat st; if (unlikely(!fname)) { FATAL("No binary supplied"); } if (strchr(fname, '/') || !(env_path = getenv("PATH"))) { target_path = ck_strdup(fname); if (stat(target_path, &st) || !S_ISREG(st.st_mode) || !(st.st_mode & 0111) || st.st_size < 4) { ck_free(target_path); FATAL("Program '%s' not found or not executable", fname); } } else { while (env_path) { u8 *cur_elem, *delim = strchr(env_path, ':'); if (delim) { cur_elem = ck_alloc(delim - env_path + 1); if (unlikely(!cur_elem)) { FATAL( "Unexpected overflow when processing ENV. This should never " "happend."); } memcpy(cur_elem, env_path, delim - env_path); delim++; } else { cur_elem = ck_strdup(env_path); } env_path = delim; if (cur_elem[0]) { target_path = alloc_printf("%s/%s", cur_elem, fname); } else { target_path = ck_strdup(fname); } ck_free(cur_elem); if (!stat(target_path, &st) && S_ISREG(st.st_mode) && (st.st_mode & 0111) && st.st_size >= 4) { break; } ck_free(target_path); target_path = NULL; } if (!target_path) { FATAL("Program '%s' not found or not executable", fname); } } return target_path; } /* Parses the kill signal environment variable, FATALs on error. If the env is not set, sets the env to default_signal for the signal handlers and returns the default_signal. */ int parse_afl_kill_signal_env(u8 *afl_kill_signal_env, int default_signal) { if (afl_kill_signal_env && afl_kill_signal_env[0]) { char *endptr; u8 signal_code; signal_code = (u8)strtoul(afl_kill_signal_env, &endptr, 10); /* Did we manage to parse the full string? */ if (*endptr != '\0' || endptr == (char *)afl_kill_signal_env) { FATAL("Invalid AFL_KILL_SIGNAL: %s (expected unsigned int)", afl_kill_signal_env); } return signal_code; } else { char *sigstr = alloc_printf("%d", default_signal); if (!sigstr) { FATAL("Failed to alloc mem for signal buf"); } /* Set the env for signal handler */ setenv("AFL_KILL_SIGNAL", sigstr, 1); free(sigstr); return default_signal; } } void check_environment_vars(char **envp) { if (be_quiet) { return; } int index = 0, issue_detected = 0; char *env, *val; while ((env = envp[index++]) != NULL) { if (strncmp(env, "ALF_", 4) == 0 || strncmp(env, "_ALF", 4) == 0 || strncmp(env, "__ALF", 5) == 0 || strncmp(env, "_AFL", 4) == 0 || strncmp(env, "__AFL", 5) == 0) { WARNF("Potentially mistyped AFL environment variable: %s", env); issue_detected = 1; } else if (strncmp(env, "AFL_", 4) == 0) { int i = 0, match = 0; while (match == 0 && afl_environment_variables[i] != NULL) { if (strncmp(env, afl_environment_variables[i], strlen(afl_environment_variables[i])) == 0 && env[strlen(afl_environment_variables[i])] == '=') { match = 1; if ((val = getenv(afl_environment_variables[i])) && !*val) { WARNF( "AFL environment variable %s defined but is empty, this can " "lead to unexpected consequences", afl_environment_variables[i]); issue_detected = 1; } } else { i++; } } i = 0; while (match == 0 && afl_environment_deprecated[i] != NULL) { if (strncmp(env, afl_environment_deprecated[i], strlen(afl_environment_deprecated[i])) == 0 && env[strlen(afl_environment_deprecated[i])] == '=') { match = 1; WARNF("AFL environment variable %s is deprecated!", afl_environment_deprecated[i]); issue_detected = 1; } else { i++; } } if (match == 0) { WARNF("Mistyped AFL environment variable: %s", env); issue_detected = 1; } } } if (issue_detected) { sleep(2); } } char *get_afl_env(char *env) { char *val; if ((val = getenv(env)) != NULL) { if (!be_quiet) { OKF("Loaded environment variable %s with value %s", env, val); } } return val; } /* Read mask bitmap from file. This is for the -B option. */ void read_bitmap(u8 *fname, u8 *map, size_t len) { s32 fd = open(fname, O_RDONLY); if (fd < 0) { PFATAL("Unable to open '%s'", fname); } ck_read(fd, map, len, fname); close(fd); } u64 get_cur_time(void) { struct timeval tv; struct timezone tz; gettimeofday(&tv, &tz); return (tv.tv_sec * 1000ULL) + (tv.tv_usec / 1000); } /* Get unix time in microseconds */ u64 get_cur_time_us(void) { struct timeval tv; struct timezone tz; gettimeofday(&tv, &tz); return (tv.tv_sec * 1000000ULL) + tv.tv_usec; } /* Describe integer. The buf should be at least 6 bytes to fit all ints we randomly see. Will return buf for convenience. */ u8 *stringify_int(u8 *buf, size_t len, u64 val) { \ #define CHK_FORMAT(_divisor, _limit_mult, _fmt, _cast) \ do { \ \ if (val < (_divisor) * (_limit_mult)) { \ \ snprintf(buf, len, _fmt, ((_cast)val) / (_divisor)); \ return buf; \ \ } \ \ } while (0) /* 0-9999 */ CHK_FORMAT(1, 10000, "%llu", u64); /* 10.0k - 99.9k */ CHK_FORMAT(1000, 99.95, "%0.01fk", double); /* 100k - 999k */ CHK_FORMAT(1000, 1000, "%lluk", u64); /* 1.00M - 9.99M */ CHK_FORMAT(1000 * 1000, 9.995, "%0.02fM", double); /* 10.0M - 99.9M */ CHK_FORMAT(1000 * 1000, 99.95, "%0.01fM", double); /* 100M - 999M */ CHK_FORMAT(1000 * 1000, 1000, "%lluM", u64); /* 1.00G - 9.99G */ CHK_FORMAT(1000LL * 1000 * 1000, 9.995, "%0.02fG", double); /* 10.0G - 99.9G */ CHK_FORMAT(1000LL * 1000 * 1000, 99.95, "%0.01fG", double); /* 100G - 999G */ CHK_FORMAT(1000LL * 1000 * 1000, 1000, "%lluG", u64); /* 1.00T - 9.99G */ CHK_FORMAT(1000LL * 1000 * 1000 * 1000, 9.995, "%0.02fT", double); /* 10.0T - 99.9T */ CHK_FORMAT(1000LL * 1000 * 1000 * 1000, 99.95, "%0.01fT", double); /* 100T+ */ strncpy(buf, "infty", len); buf[len - 1] = '\0'; return buf; } /* Describe float. Similar as int. */ u8 *stringify_float(u8 *buf, size_t len, double val) { if (val < 99.995) { snprintf(buf, len, "%0.02f", val); } else if (val < 999.95) { snprintf(buf, len, "%0.01f", val); } else if (unlikely(isnan(val) || isinf(val))) { strcpy(buf, "inf"); } else { stringify_int(buf, len, (u64)val); } return buf; } /* Describe integer as memory size. */ u8 *stringify_mem_size(u8 *buf, size_t len, u64 val) { /* 0-9999 */ CHK_FORMAT(1, 10000, "%llu B", u64); /* 10.0k - 99.9k */ CHK_FORMAT(1024, 99.95, "%0.01f kB", double); /* 100k - 999k */ CHK_FORMAT(1024, 1000, "%llu kB", u64); /* 1.00M - 9.99M */ CHK_FORMAT(1024 * 1024, 9.995, "%0.02f MB", double); /* 10.0M - 99.9M */ CHK_FORMAT(1024 * 1024, 99.95, "%0.01f MB", double); /* 100M - 999M */ CHK_FORMAT(1024 * 1024, 1000, "%llu MB", u64); /* 1.00G - 9.99G */ CHK_FORMAT(1024LL * 1024 * 1024, 9.995, "%0.02f GB", double); /* 10.0G - 99.9G */ CHK_FORMAT(1024LL * 1024 * 1024, 99.95, "%0.01f GB", double); /* 100G - 999G */ CHK_FORMAT(1024LL * 1024 * 1024, 1000, "%llu GB", u64); /* 1.00T - 9.99G */ CHK_FORMAT(1024LL * 1024 * 1024 * 1024, 9.995, "%0.02f TB", double); /* 10.0T - 99.9T */ CHK_FORMAT(1024LL * 1024 * 1024 * 1024, 99.95, "%0.01f TB", double); #undef CHK_FORMAT /* 100T+ */ strncpy(buf, "infty", len - 1); buf[len - 1] = '\0'; return buf; } /* Describe time delta as string. Returns a pointer to buf for convenience. */ u8 *stringify_time_diff(u8 *buf, size_t len, u64 cur_ms, u64 event_ms) { if (!event_ms) { snprintf(buf, len, "none seen yet"); } else { u64 delta; s32 t_d, t_h, t_m, t_s; u8 val_buf[STRINGIFY_VAL_SIZE_MAX]; delta = cur_ms - event_ms; t_d = delta / 1000 / 60 / 60 / 24; t_h = (delta / 1000 / 60 / 60) % 24; t_m = (delta / 1000 / 60) % 60; t_s = (delta / 1000) % 60; stringify_int(val_buf, sizeof(val_buf), t_d); snprintf(buf, len, "%s days, %d hrs, %d min, %d sec", val_buf, t_h, t_m, t_s); } return buf; } /* Unsafe Describe integer. The buf sizes are not checked. This is unsafe but fast. Will return buf for convenience. */ u8 *u_stringify_int(u8 *buf, u64 val) { \ #define CHK_FORMAT(_divisor, _limit_mult, _fmt, _cast) \ do { \ \ if (val < (_divisor) * (_limit_mult)) { \ \ sprintf(buf, _fmt, ((_cast)val) / (_divisor)); \ return buf; \ \ } \ \ } while (0) /* 0-9999 */ CHK_FORMAT(1, 10000, "%llu", u64); /* 10.0k - 99.9k */ CHK_FORMAT(1000, 99.95, "%0.01fk", double); /* 100k - 999k */ CHK_FORMAT(1000, 1000, "%lluk", u64); /* 1.00M - 9.99M */ CHK_FORMAT(1000 * 1000, 9.995, "%0.02fM", double); /* 10.0M - 99.9M */ CHK_FORMAT(1000 * 1000, 99.95, "%0.01fM", double); /* 100M - 999M */ CHK_FORMAT(1000 * 1000, 1000, "%lluM", u64); /* 1.00G - 9.99G */ CHK_FORMAT(1000LL * 1000 * 1000, 9.995, "%0.02fG", double); /* 10.0G - 99.9G */ CHK_FORMAT(1000LL * 1000 * 1000, 99.95, "%0.01fG", double); /* 100G - 999G */ CHK_FORMAT(1000LL * 1000 * 1000, 1000, "%lluG", u64); /* 1.00T - 9.99G */ CHK_FORMAT(1000LL * 1000 * 1000 * 1000, 9.995, "%0.02fT", double); /* 10.0T - 99.9T */ CHK_FORMAT(1000LL * 1000 * 1000 * 1000, 99.95, "%0.01fT", double); /* 100T+ */ strcpy(buf, "infty"); return buf; } /* Unsafe describe float. Similar as unsafe int. */ u8 *u_stringify_float(u8 *buf, double val) { if (val < 99.995) { sprintf(buf, "%0.02f", val); } else if (val < 999.95) { sprintf(buf, "%0.01f", val); } else if (unlikely(isnan(val) || isinf(val))) { strcpy(buf, "infinite"); } else { return u_stringify_int(buf, (u64)val); } return buf; } /* Unsafe describe integer as memory size. */ u8 *u_stringify_mem_size(u8 *buf, u64 val) { /* 0-9999 */ CHK_FORMAT(1, 10000, "%llu B", u64); /* 10.0k - 99.9k */ CHK_FORMAT(1024, 99.95, "%0.01f kB", double); /* 100k - 999k */ CHK_FORMAT(1024, 1000, "%llu kB", u64); /* 1.00M - 9.99M */ CHK_FORMAT(1024 * 1024, 9.995, "%0.02f MB", double); /* 10.0M - 99.9M */ CHK_FORMAT(1024 * 1024, 99.95, "%0.01f MB", double); /* 100M - 999M */ CHK_FORMAT(1024 * 1024, 1000, "%llu MB", u64); /* 1.00G - 9.99G */ CHK_FORMAT(1024LL * 1024 * 1024, 9.995, "%0.02f GB", double); /* 10.0G - 99.9G */ CHK_FORMAT(1024LL * 1024 * 1024, 99.95, "%0.01f GB", double); /* 100G - 999G */ CHK_FORMAT(1024LL * 1024 * 1024, 1000, "%llu GB", u64); /* 1.00T - 9.99G */ CHK_FORMAT(1024LL * 1024 * 1024 * 1024, 9.995, "%0.02f TB", double); /* 10.0T - 99.9T */ CHK_FORMAT(1024LL * 1024 * 1024 * 1024, 99.95, "%0.01f TB", double); #undef CHK_FORMAT /* 100T+ */ strcpy(buf, "infty"); return buf; } /* Unsafe describe time delta as string. Returns a pointer to buf for convenience. */ u8 *u_stringify_time_diff(u8 *buf, u64 cur_ms, u64 event_ms) { if (!event_ms) { sprintf(buf, "none seen yet"); } else { u64 delta; s32 t_d, t_h, t_m, t_s; u8 val_buf[STRINGIFY_VAL_SIZE_MAX]; delta = cur_ms - event_ms; t_d = delta / 1000 / 60 / 60 / 24; t_h = (delta / 1000 / 60 / 60) % 24; t_m = (delta / 1000 / 60) % 60; t_s = (delta / 1000) % 60; u_stringify_int(val_buf, t_d); sprintf(buf, "%s days, %d hrs, %d min, %d sec", val_buf, t_h, t_m, t_s); } return buf; } /* Reads the map size from ENV */ u32 get_map_size(void) { uint32_t map_size = MAP_SIZE; char * ptr; if ((ptr = getenv("AFL_MAP_SIZE")) || (ptr = getenv("AFL_MAPSIZE"))) { map_size = atoi(ptr); if (!map_size || map_size > (1 << 29)) { FATAL("illegal AFL_MAP_SIZE %u, must be between %u and %u", map_size, 32U, 1U << 29); } if (map_size % 32) { map_size = (((map_size >> 5) + 1) << 5); } } return map_size; } /* Create a stream file */ FILE *create_ffile(u8 *fn) { s32 fd; FILE *f; fd = open(fn, O_WRONLY | O_CREAT | O_TRUNC, 0600); if (fd < 0) { PFATAL("Unable to create '%s'", fn); } f = fdopen(fd, "w"); if (!f) { PFATAL("fdopen() failed"); } return f; } /* Create a file */ s32 create_file(u8 *fn) { s32 fd; fd = open(fn, O_WRONLY | O_CREAT | O_TRUNC, 0600); if (fd < 0) { PFATAL("Unable to create '%s'", fn); } return fd; }