From d4fb7f8b4015297e1c74b28d671eba058cfb6366 Mon Sep 17 00:00:00 2001 From: realmadsci <71108352+realmadsci@users.noreply.github.com> Date: Fri, 12 Mar 2021 15:53:42 -0500 Subject: Add AFL_QEMU_CUSTOM_BIN environment flag In QEMU mode (-Q), setting AFL_QEMU_CUSTOM_BIN cause afl-fuzz to skip prepending afl-qemu-trace to your command line. Use this if you wish to use a custom afl-qemu-trace or if you need to modify the afl-qemu-trace arguments. --- src/afl-common.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'src/afl-common.c') diff --git a/src/afl-common.c b/src/afl-common.c index 9f6eb564..58fbf765 100644 --- a/src/afl-common.c +++ b/src/afl-common.c @@ -149,6 +149,13 @@ void argv_cpy_free(char **argv) { char **get_qemu_argv(u8 *own_loc, u8 **target_path_p, int argc, char **argv) { + if (unlikely(getenv("AFL_QEMU_CUSTOM_BIN"))) { + WARNF( + "AFL_QEMU_CUSTOM_BIN is enabled. " + "You must run your target under afl-qemu-trace on your own!"); + return argv; + } + if (!unlikely(own_loc)) { FATAL("BUG: param own_loc is NULL"); } u8 *tmp, *cp = NULL, *rsl, *own_copy; -- cgit v1.2.3 From 01ad7610beaf772063c9011daae5fa3a3232494c Mon Sep 17 00:00:00 2001 From: realmadsci <71108352+realmadsci@users.noreply.github.com> Date: Mon, 15 Mar 2021 11:45:58 -0400 Subject: Remove AFL_PRELOAD and AFL_USE_QASAN handlers These are now processed in afl-qemu-trace so that the "copy+paste" code that is in all of the other AFL tools can be removed. This also allows the AFL_USE_QASAN flag to work the same when used with tools like afl-fuzz as it does with afl-qemu-trace. This is important in situations where loading the QASAN library changes the address of your desired entrypoint, or for crash validation using the same environment that afl-fuzz was using. With this change, the same set of environment variables can be used in exactly the same way between afl-fuzz, afl-showmap, and afl-qemu-trace, and you will get exactly the same guest environment. --- src/afl-common.c | 60 -------------------------------------------------------- 1 file changed, 60 deletions(-) (limited to 'src/afl-common.c') diff --git a/src/afl-common.c b/src/afl-common.c index 9f6eb564..5ac50595 100644 --- a/src/afl-common.c +++ b/src/afl-common.c @@ -338,66 +338,6 @@ char **get_wine_argv(u8 *own_loc, u8 **target_path_p, int argc, char **argv) { } -/* Get libqasan path. */ - -u8 *get_libqasan_path(u8 *own_loc) { - - if (!unlikely(own_loc)) { FATAL("BUG: param own_loc is NULL"); } - - u8 *tmp, *cp = NULL, *rsl, *own_copy; - - tmp = getenv("AFL_PATH"); - - if (tmp) { - - cp = alloc_printf("%s/libqasan.so", tmp); - - if (access(cp, X_OK)) { FATAL("Unable to find '%s'", tmp); } - - return cp; - - } - - own_copy = ck_strdup(own_loc); - rsl = strrchr(own_copy, '/'); - - if (rsl) { - - *rsl = 0; - - cp = alloc_printf("%s/libqasan.so", own_copy); - ck_free(own_copy); - - if (!access(cp, X_OK)) { return cp; } - - } else { - - ck_free(own_copy); - - } - - if (!access(AFL_PATH "/libqasan.so", X_OK)) { - - if (cp) { ck_free(cp); } - - return ck_strdup(AFL_PATH "/libqasan.so"); - - } - - SAYF("\n" cLRD "[-] " cRST - "Oops, unable to find the 'libqasan.so' binary. The binary must be " - "built\n" - " separately by following the instructions in " - "qemu_mode/libqasan/README.md. " - "If you\n" - " already have the binary installed, you may need to specify " - "AFL_PATH in the\n" - " environment.\n"); - - FATAL("Failed to locate 'libqasan.so'."); - -} - /* Find binary, used by analyze, showmap, tmin @returns the path, allocating the string */ -- cgit v1.2.3 From 862cb3217f5983e5cfff6568f6b31fcf1e960802 Mon Sep 17 00:00:00 2001 From: vanhauser-thc Date: Tue, 16 Mar 2021 14:38:13 +0100 Subject: fix cmplog rtn --- src/afl-common.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'src/afl-common.c') diff --git a/src/afl-common.c b/src/afl-common.c index bfb05a67..27b63434 100644 --- a/src/afl-common.c +++ b/src/afl-common.c @@ -150,10 +150,12 @@ void argv_cpy_free(char **argv) { char **get_qemu_argv(u8 *own_loc, u8 **target_path_p, int argc, char **argv) { if (unlikely(getenv("AFL_QEMU_CUSTOM_BIN"))) { + WARNF( - "AFL_QEMU_CUSTOM_BIN is enabled. " - "You must run your target under afl-qemu-trace on your own!"); + "AFL_QEMU_CUSTOM_BIN is enabled. " + "You must run your target under afl-qemu-trace on your own!"); return argv; + } if (!unlikely(own_loc)) { FATAL("BUG: param own_loc is NULL"); } -- cgit v1.2.3 From 5e2a5f1110e29c36f1c41fb4677ab698c5d571c0 Mon Sep 17 00:00:00 2001 From: vanhauser-thc Date: Wed, 17 Mar 2021 10:26:02 +0100 Subject: shmem map size in config.h --- src/afl-common.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'src/afl-common.c') diff --git a/src/afl-common.c b/src/afl-common.c index 27b63434..7e56ce3f 100644 --- a/src/afl-common.c +++ b/src/afl-common.c @@ -1072,7 +1072,7 @@ u8 *u_stringify_time_diff(u8 *buf, u64 cur_ms, u64 event_ms) { /* Reads the map size from ENV */ u32 get_map_size(void) { - uint32_t map_size = 8000000; // a very large default map + uint32_t map_size = DEFAULT_SHMEM_SIZE; char * ptr; if ((ptr = getenv("AFL_MAP_SIZE")) || (ptr = getenv("AFL_MAPSIZE"))) { -- cgit v1.2.3 From e73c7c59c14d0bff1c1b25aa264fe18b7cdcddaf Mon Sep 17 00:00:00 2001 From: vanhauser-thc Date: Fri, 19 Mar 2021 14:55:25 +0100 Subject: refactor finding binaries --- src/afl-common.c | 228 +++++++++++++++++-------------------------------------- 1 file changed, 70 insertions(+), 158 deletions(-) (limited to 'src/afl-common.c') diff --git a/src/afl-common.c b/src/afl-common.c index 7e56ce3f..04736901 100644 --- a/src/afl-common.c +++ b/src/afl-common.c @@ -158,10 +158,6 @@ 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"); } @@ -173,70 +169,8 @@ char **get_qemu_argv(u8 *own_loc, u8 **target_path_p, int argc, char **argv) { /* 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'."); + *target_path_p = new_argv[0] = find_afl_binary(own_loc, "afl-qemu-trace"); + return new_argv; } @@ -244,10 +178,6 @@ char **get_qemu_argv(u8 *own_loc, u8 **target_path_p, int argc, char **argv) { 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"); } @@ -258,92 +188,10 @@ char **get_wine_argv(u8 *own_loc, u8 **target_path_p, int argc, char **argv) { /* 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); + u8 *tmp = find_afl_binary(own_loc, "afl-qemu-trace"); + ck_free(tmp); + *target_path_p = new_argv[0] = find_afl_binary(own_loc, "afl-wine-trace"); + return new_argv; } @@ -437,6 +285,70 @@ u8 *find_binary(u8 *fname) { } +u8 *find_afl_binary(u8 *own_loc, u8 *fname) { + + u8 *afl_path = NULL, *target_path, *own_copy; + + if ((afl_path = getenv("AFL_PATH"))) { + + target_path = alloc_printf("%s/%s", afl_path, fname); + if (!access(target_path, X_OK)) { + + return target_path; + + } else { + + ck_free(target_path); + + } + + } + + if (own_loc) { + + own_copy = ck_strdup(own_loc); + u8 *rsl = strrchr(own_copy, '/'); + + if (rsl) { + + *rsl = 0; + + target_path = alloc_printf("%s/%s", own_copy, fname); + ck_free(own_copy); + + if (!access(target_path, X_OK)) { + + return target_path; + + } else { + + ck_free(target_path); + + } + + } else { + + ck_free(own_copy); + + } + + } + + target_path = alloc_printf("%s/%s", BIN_PATH, fname); + if (!access(target_path, X_OK)) { + + return target_path; + + } else { + + ck_free(target_path); + + } + + return find_binary(fname); + +} + /* 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. */ -- cgit v1.2.3 From d7e121e2c99c02d4b6984f21ba837d44bce9c77c Mon Sep 17 00:00:00 2001 From: fuzzah Date: Wed, 17 Mar 2021 01:51:40 +0300 Subject: add AFL_TARGET_ENV to afl-fuzz --- src/afl-common.c | 96 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 96 insertions(+) (limited to 'src/afl-common.c') diff --git a/src/afl-common.c b/src/afl-common.c index 27b63434..72a95fbc 100644 --- a/src/afl-common.c +++ b/src/afl-common.c @@ -706,6 +706,102 @@ char *get_afl_env(char *env) { } +u8 extract_and_set_env(u8 *env_str) { + + if (!env_str) { return 0; } + + u8 *p = ck_strdup(env_str); + + u8 *end = p + strlen((char *)p); + + u8 ret_val = 0; // return false by default + + u8 *rest = p; + u8 *key = p; + u8 *val = p; + + u8 closing_sym = ' '; + u8 c; + + size_t num_pairs = 0; + + while (rest < end) { + + while (*rest == ' ') { + + rest++; + + } + + if (rest + 1 >= end) break; + + key = rest; + // env variable names may not start with numbers or '=' + if (*key == '=' || (*key >= '0' && *key <= '9')) { goto free_and_return; } + + while (rest < end && *rest != '=' && *rest != ' ') { + + c = *rest; + // lowercase is bad but we may still allow it + if ((c < 'A' || c > 'Z') && (c < 'a' || c > 'z') && + (c < '0' || c > '9') && c != '_') { + + goto free_and_return; + + } + + rest++; + + } + + if (*rest != '=') { goto free_and_return; } + + *rest = '\0'; // done with variable name + + rest += 1; + if (rest >= end || *rest == ' ') { goto free_and_return; } + + val = rest; + if (*val == '\'' || *val == '"') { + + closing_sym = *val; + val += 1; + rest += 1; + if (rest >= end) { goto free_and_return; } + + } else { + + closing_sym = ' '; + + } + + while (rest < end && *rest != closing_sym) { + + rest++; + + } + + if (closing_sym != ' ' && *rest != closing_sym) { goto free_and_return; } + + *rest = '\0'; // done with variable value + + rest += 1; + if (rest < end && *rest != ' ') { goto free_and_return; } + + num_pairs += 1; + + setenv(key, val, 1); + + } + + if (num_pairs > 0) { ret_val = 1; } + +free_and_return: + ck_free(p); + return ret_val; + +} + /* Read mask bitmap from file. This is for the -B option. */ void read_bitmap(u8 *fname, u8 *map, size_t len) { -- cgit v1.2.3 From 5fcd634f05049564dde59df420ac1c2f291a2fb0 Mon Sep 17 00:00:00 2001 From: Dominik Maier Date: Tue, 23 Mar 2021 18:47:07 +0100 Subject: fixed tiny nitpicks --- src/afl-common.c | 22 +++++++++------------- 1 file changed, 9 insertions(+), 13 deletions(-) (limited to 'src/afl-common.c') diff --git a/src/afl-common.c b/src/afl-common.c index 6e485117..cd24c376 100644 --- a/src/afl-common.c +++ b/src/afl-common.c @@ -618,19 +618,15 @@ char *get_afl_env(char *env) { } -u8 extract_and_set_env(u8 *env_str) { +bool extract_and_set_env(u8 *env_str) { - if (!env_str) { return 0; } + if (!env_str) { return false; } - u8 *p = ck_strdup(env_str); + bool ret = false; // return false by default + u8 *p = ck_strdup(env_str); u8 *end = p + strlen((char *)p); - - u8 ret_val = 0; // return false by default - u8 *rest = p; - u8 *key = p; - u8 *val = p; u8 closing_sym = ' '; u8 c; @@ -647,7 +643,7 @@ u8 extract_and_set_env(u8 *env_str) { if (rest + 1 >= end) break; - key = rest; + u8 *key = rest; // env variable names may not start with numbers or '=' if (*key == '=' || (*key >= '0' && *key <= '9')) { goto free_and_return; } @@ -673,7 +669,7 @@ u8 extract_and_set_env(u8 *env_str) { rest += 1; if (rest >= end || *rest == ' ') { goto free_and_return; } - val = rest; + u8 *val = rest; if (*val == '\'' || *val == '"') { closing_sym = *val; @@ -700,17 +696,17 @@ u8 extract_and_set_env(u8 *env_str) { rest += 1; if (rest < end && *rest != ' ') { goto free_and_return; } - num_pairs += 1; + num_pairs++; setenv(key, val, 1); } - if (num_pairs > 0) { ret_val = 1; } + if (num_pairs) { ret = true; } free_and_return: ck_free(p); - return ret_val; + return ret; } -- cgit v1.2.3 From dfe6f7f8c949744eeab7a401affde93729a5b39d Mon Sep 17 00:00:00 2001 From: vanhauser-thc Date: Tue, 23 Mar 2021 20:20:59 +0100 Subject: make setting different file permissions easy via config.h --- src/afl-common.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'src/afl-common.c') diff --git a/src/afl-common.c b/src/afl-common.c index cd24c376..37b4788c 100644 --- a/src/afl-common.c +++ b/src/afl-common.c @@ -1104,7 +1104,7 @@ FILE *create_ffile(u8 *fn) { s32 fd; FILE *f; - fd = open(fn, O_WRONLY | O_CREAT | O_TRUNC, 0600); + fd = open(fn, O_WRONLY | O_CREAT | O_TRUNC, DEFAULT_PERMISSION); if (fd < 0) { PFATAL("Unable to create '%s'", fn); } @@ -1122,7 +1122,7 @@ s32 create_file(u8 *fn) { s32 fd; - fd = open(fn, O_WRONLY | O_CREAT | O_TRUNC, 0600); + fd = open(fn, O_WRONLY | O_CREAT | O_TRUNC, DEFAULT_PERMISSION); if (fd < 0) { PFATAL("Unable to create '%s'", fn); } -- cgit v1.2.3