diff options
| -rw-r--r-- | frida_mode/README.md | 4 | ||||
| -rw-r--r-- | frida_mode/src/persistent/persistent.c | 13 | ||||
| -rw-r--r-- | frida_mode/src/persistent/persistent_arm64.c | 12 | ||||
| -rw-r--r-- | frida_mode/src/persistent/persistent_x64.c | 53 | ||||
| -rw-r--r-- | frida_mode/src/persistent/persistent_x86.c | 40 | ||||
| -rw-r--r-- | frida_mode/test/persistent_ret/GNUmakefile | 5 | ||||
| -rw-r--r-- | include/envs.h | 1 |
7 files changed, 81 insertions, 47 deletions
diff --git a/frida_mode/README.md b/frida_mode/README.md index d7dd72a0..9b316cb9 100644 --- a/frida_mode/README.md +++ b/frida_mode/README.md @@ -75,7 +75,6 @@ following options are currently supported: * `AFL_FRIDA_PERSISTENT_CNT` - See `AFL_QEMU_PERSISTENT_CNT` * `AFL_FRIDA_PERSISTENT_HOOK` - See `AFL_QEMU_PERSISTENT_HOOK` * `AFL_FRIDA_PERSISTENT_RET` - See `AFL_QEMU_PERSISTENT_RET` -* `AFL_FRIDA_PERSISTENT_RETADDR_OFFSET` - See `AFL_QEMU_PERSISTENT_RETADDR_OFFSET` To enable the powerful CMPLOG mechanism, set `-c 0` for `afl-fuzz`. @@ -164,8 +163,7 @@ application to the named file (supersedes the setting of `AFL_DEBUG_CHILD`) application to the named file (supersedes the setting of `AFL_DEBUG_CHILD`) * `AFL_FRIDA_PERSISTENT_DEBUG` - Insert a Breakpoint into the instrumented code at `AFL_FRIDA_PERSISTENT_HOOK` and `AFL_FRIDA_PERSISTENT_RET` to allow the user -to determine the value of `AFL_FRIDA_PERSISTENT_RETADDR_OFFSET` using a -debugger. +to detect issues in the persistent loop using a debugger. ``` diff --git a/frida_mode/src/persistent/persistent.c b/frida_mode/src/persistent/persistent.c index 2ec5b9cc..243d501d 100644 --- a/frida_mode/src/persistent/persistent.c +++ b/frida_mode/src/persistent/persistent.c @@ -13,7 +13,6 @@ afl_persistent_hook_fn hook = NULL; guint64 persistent_start = 0; guint64 persistent_count = 0; guint64 persistent_ret = 0; -guint64 persistent_ret_offset = 0; gboolean persistent_debug = FALSE; void persistent_init(void) { @@ -23,8 +22,6 @@ void persistent_init(void) { persistent_start = util_read_address("AFL_FRIDA_PERSISTENT_ADDR"); persistent_count = util_read_num("AFL_FRIDA_PERSISTENT_CNT"); persistent_ret = util_read_address("AFL_FRIDA_PERSISTENT_RET"); - persistent_ret_offset = - util_read_address("AFL_FRIDA_PERSISTENT_RETADDR_OFFSET"); if (getenv("AFL_FRIDA_PERSISTENT_DEBUG") != NULL) { persistent_debug = TRUE; } @@ -44,14 +41,6 @@ void persistent_init(void) { } - if (persistent_ret_offset != 0 && persistent_ret == 0) { - - FATAL( - "AFL_FRIDA_PERSISTENT_RET must be specified if " - "AFL_FRIDA_PERSISTENT_RETADDR_OFFSET is"); - - } - if (persistent_start != 0 && persistent_count == 0) persistent_count = 1000; if (persistent_count != 0 && persistent_count < 100) @@ -68,8 +57,6 @@ void persistent_init(void) { OKF("Instrumentation - persistent ret [%c] (0x%016" G_GINT64_MODIFIER "X)", persistent_ret == 0 ? ' ' : 'X', persistent_ret); - OKF("Instrumentation - persistent ret offset [%c] (%" G_GINT64_MODIFIER "d)", - persistent_ret_offset == 0 ? ' ' : 'X', persistent_ret_offset); if (hook_name != NULL) { diff --git a/frida_mode/src/persistent/persistent_arm64.c b/frida_mode/src/persistent/persistent_arm64.c index b23693fe..d7c6c76b 100644 --- a/frida_mode/src/persistent/persistent_arm64.c +++ b/frida_mode/src/persistent/persistent_arm64.c @@ -268,13 +268,15 @@ static void instrument_persitent_restore_regs(GumArm64Writer * cw, ARM64_REG_X0, (16 * 14), GUM_INDEX_SIGNED_OFFSET); - /* Don't restore RIP or RSP, use x1-x3 as clobber */ - - /* LR & Adjusted SP (clobber x1) */ + /* LR & Adjusted SP (use x1 as clobber) */ gum_arm64_writer_put_ldp_reg_reg_reg_offset(cw, ARM64_REG_X30, ARM64_REG_X1, ARM64_REG_X0, (16 * 15), GUM_INDEX_SIGNED_OFFSET); + gum_arm64_writer_put_mov_reg_reg(cw, ARM64_REG_SP, ARM64_REG_X1); + + /* Don't restore RIP use x1-x3 as clobber */ + /* PC (x2) & CPSR (x1) */ gum_arm64_writer_put_ldp_reg_reg_reg_offset(cw, ARM64_REG_X2, ARM64_REG_X1, ARM64_REG_X0, (16 * 16), @@ -404,7 +406,6 @@ void persistent_prologue(GumStalkerOutput *output) { gconstpointer loop = cw->code + 1; - /* Stack must be 16-byte aligned per ABI */ instrument_persitent_save_regs(cw, &saved_regs); /* loop: */ @@ -450,9 +451,6 @@ void persistent_epilogue(GumStalkerOutput *output) { if (persistent_debug) { gum_arm64_writer_put_brk_imm(cw, 0); } - gum_arm64_writer_put_add_reg_reg_imm(cw, ARM64_REG_SP, ARM64_REG_SP, - persistent_ret_offset); - gum_arm64_writer_put_ldr_reg_address(cw, ARM64_REG_X0, GUM_ADDRESS(&saved_lr)); diff --git a/frida_mode/src/persistent/persistent_x64.c b/frida_mode/src/persistent/persistent_x64.c index 858ad38e..653acefe 100644 --- a/frida_mode/src/persistent/persistent_x64.c +++ b/frida_mode/src/persistent/persistent_x64.c @@ -43,6 +43,7 @@ struct x86_64_regs { typedef struct x86_64_regs arch_api_regs; static arch_api_regs saved_regs = {0}; +static gpointer saved_ret = NULL; gboolean persistent_is_supported(void) { @@ -104,7 +105,7 @@ static void instrument_persitent_save_regs(GumX86Writer * cw, /* RED_ZONE + Saved flags, RAX, alignment */ gum_x86_writer_put_add_reg_imm(cw, GUM_REG_RBX, - GUM_RED_ZONE_SIZE + (0x8 * 3)); + GUM_RED_ZONE_SIZE + (0x8 * 2)); gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_RAX, (0x8 * 16), GUM_REG_RBX); @@ -159,7 +160,9 @@ static void instrument_persitent_restore_regs(GumX86Writer * cw, gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_R15, GUM_REG_RAX, (0x8 * 14)); - /* Don't restore RIP or RSP */ + /* Don't restore RIP */ + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_RSP, GUM_REG_RAX, + (0x8 * 16)); /* Restore RBX, RAX & Flags */ gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_RSP, GUM_REG_RSP, @@ -242,6 +245,31 @@ static void persistent_prologue_hook(GumX86Writer * cw, } +static void instrument_persitent_save_ret(GumX86Writer *cw) { + + /* Stack usage by this function */ + gssize offset = GUM_RED_ZONE_SIZE + (3 * 8); + gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_RSP, GUM_REG_RSP, + -(GUM_RED_ZONE_SIZE)); + + gum_x86_writer_put_pushfx(cw); + gum_x86_writer_put_push_reg(cw, GUM_REG_RAX); + gum_x86_writer_put_push_reg(cw, GUM_REG_RBX); + + gum_x86_writer_put_mov_reg_address(cw, GUM_REG_RAX, GUM_ADDRESS(&saved_ret)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_RBX, GUM_REG_RSP, + offset); + gum_x86_writer_put_mov_reg_ptr_reg(cw, GUM_REG_RAX, GUM_REG_RBX); + + gum_x86_writer_put_pop_reg(cw, GUM_REG_RBX); + gum_x86_writer_put_pop_reg(cw, GUM_REG_RAX); + gum_x86_writer_put_popfx(cw); + + gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_RSP, GUM_REG_RSP, + (GUM_RED_ZONE_SIZE)); + +} + void persistent_prologue(GumStalkerOutput *output) { /* @@ -268,11 +296,10 @@ void persistent_prologue(GumStalkerOutput *output) { gconstpointer loop = cw->code + 1; - /* Stack must be 16-byte aligned per ABI */ - instrument_persitent_save_regs(cw, &saved_regs); + /* Pop the return value */ + gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_RSP, GUM_REG_RSP, 8); - /* pop the return value */ - gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_RSP, GUM_REG_RSP, (8)); + instrument_persitent_save_regs(cw, &saved_regs); /* loop: */ gum_x86_writer_put_label(cw, loop); @@ -304,6 +331,8 @@ void persistent_prologue(GumStalkerOutput *output) { /* original: */ gum_x86_writer_put_label(cw, original); + instrument_persitent_save_ret(cw); + if (persistent_debug) { gum_x86_writer_put_breakpoint(cw); } } @@ -314,9 +343,15 @@ void persistent_epilogue(GumStalkerOutput *output) { if (persistent_debug) { gum_x86_writer_put_breakpoint(cw); } - gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_RSP, GUM_REG_RSP, - persistent_ret_offset); - gum_x86_writer_put_ret(cw); + /* The stack should be aligned when we re-enter our loop */ + gconstpointer zero = cw->code + 1; + gum_x86_writer_put_test_reg_u32(cw, GUM_REG_RSP, 0xF); + gum_x86_writer_put_jcc_near_label(cw, X86_INS_JE, zero, GUM_NO_HINT); + gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_RSP, GUM_REG_RSP, -8); + gum_x86_writer_put_label(cw, zero); + + gum_x86_writer_put_mov_reg_address(cw, GUM_REG_RAX, GUM_ADDRESS(&saved_ret)); + gum_x86_writer_put_jmp_reg_ptr(cw, GUM_REG_RAX); } diff --git a/frida_mode/src/persistent/persistent_x86.c b/frida_mode/src/persistent/persistent_x86.c index 0675edf4..7add6e99 100644 --- a/frida_mode/src/persistent/persistent_x86.c +++ b/frida_mode/src/persistent/persistent_x86.c @@ -39,6 +39,7 @@ struct x86_regs { typedef struct x86_regs arch_api_regs; static arch_api_regs saved_regs = {0}; +static gpointer saved_ret = NULL; gboolean persistent_is_supported(void) { @@ -117,7 +118,9 @@ static void instrument_persitent_restore_regs(GumX86Writer * cw, gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_EBP, GUM_REG_EAX, (0x4 * 6)); - /* Don't restore RIP or RSP */ + /* Don't restore RIP */ + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_ESP, GUM_REG_EAX, + (0x4 * 8)); /* Restore RBX, RAX & Flags */ gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_EBX, GUM_REG_EAX, @@ -184,6 +187,26 @@ static void persistent_prologue_hook(GumX86Writer *cw, struct x86_regs *regs) { } +static void instrument_persitent_save_ret(GumX86Writer *cw) { + + /* Stack usage by this function */ + gssize offset = (3 * 4); + + gum_x86_writer_put_pushfx(cw); + gum_x86_writer_put_push_reg(cw, GUM_REG_EAX); + gum_x86_writer_put_push_reg(cw, GUM_REG_EBX); + + gum_x86_writer_put_mov_reg_address(cw, GUM_REG_EAX, GUM_ADDRESS(&saved_ret)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_EBX, GUM_REG_ESP, + offset); + gum_x86_writer_put_mov_reg_ptr_reg(cw, GUM_REG_EAX, GUM_REG_EBX); + + gum_x86_writer_put_pop_reg(cw, GUM_REG_EBX); + gum_x86_writer_put_pop_reg(cw, GUM_REG_EAX); + gum_x86_writer_put_popfx(cw); + +} + void persistent_prologue(GumStalkerOutput *output) { /* @@ -210,11 +233,10 @@ void persistent_prologue(GumStalkerOutput *output) { gconstpointer loop = cw->code + 1; - /* Stack must be 16-byte aligned per ABI */ - instrument_persitent_save_regs(cw, &saved_regs); - /* Pop the return value */ - gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_ESP, GUM_REG_ESP, (4)); + gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_ESP, GUM_REG_ESP, 4); + + instrument_persitent_save_regs(cw, &saved_regs); /* loop: */ gum_x86_writer_put_label(cw, loop); @@ -244,6 +266,8 @@ void persistent_prologue(GumStalkerOutput *output) { /* original: */ gum_x86_writer_put_label(cw, original); + instrument_persitent_save_ret(cw); + if (persistent_debug) { gum_x86_writer_put_breakpoint(cw); } } @@ -254,10 +278,8 @@ void persistent_epilogue(GumStalkerOutput *output) { if (persistent_debug) { gum_x86_writer_put_breakpoint(cw); } - gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_ESP, GUM_REG_ESP, - persistent_ret_offset); - - gum_x86_writer_put_ret(cw); + gum_x86_writer_put_mov_reg_address(cw, GUM_REG_EAX, GUM_ADDRESS(&saved_ret)); + gum_x86_writer_put_jmp_reg_ptr(cw, GUM_REG_EAX); } diff --git a/frida_mode/test/persistent_ret/GNUmakefile b/frida_mode/test/persistent_ret/GNUmakefile index 4c9d8a19..2de51d86 100644 --- a/frida_mode/test/persistent_ret/GNUmakefile +++ b/frida_mode/test/persistent_ret/GNUmakefile @@ -38,8 +38,6 @@ ifeq "$(ARCH)" "x86" AFL_FRIDA_PERSISTENT_RET=$(shell $(PWD)get_symbol_addr.py -f $(TESTINSTBIN) -s slow -b 0x56555000) endif -AFL_FRIDA_PERSISTENT_RETADDR_OFFSET:=0x50 - .PHONY: all 32 clean qemu frida all: $(TESTINSTBIN) @@ -76,7 +74,6 @@ frida: $(TESTINSTBIN) $(TESTINSTR_DATA_FILE) frida_ret: $(TESTINSTBIN) $(TESTINSTR_DATA_FILE) AFL_FRIDA_PERSISTENT_ADDR=$(AFL_FRIDA_PERSISTENT_ADDR) \ AFL_FRIDA_PERSISTENT_RET=$(AFL_FRIDA_PERSISTENT_RET) \ - AFL_FRIDA_PERSISTENT_RETADDR_OFFSET=$(AFL_FRIDA_PERSISTENT_RETADDR_OFFSET) \ $(ROOT)afl-fuzz \ -D \ -O \ @@ -89,7 +86,6 @@ debug: $(TESTINSTBIN) $(TESTINSTR_DATA_FILE) gdb \ --ex 'set environment AFL_FRIDA_PERSISTENT_ADDR=$(AFL_FRIDA_PERSISTENT_ADDR)' \ --ex 'set environment AFL_FRIDA_PERSISTENT_RET=$(AFL_FRIDA_PERSISTENT_RET)' \ - --ex 'set environment AFL_FRIDA_PERSISTENT_RETADDR_OFFSET=$(AFL_FRIDA_PERSISTENT_RETADDR_OFFSET)' \ --ex 'set environment AFL_FRIDA_PERSISTENT_DEBUG=1' \ --ex 'set environment AFL_DEBUG_CHILD=1' \ --ex 'set environment LD_PRELOAD=$(ROOT)afl-frida-trace.so' \ @@ -99,7 +95,6 @@ debug: $(TESTINSTBIN) $(TESTINSTR_DATA_FILE) run: $(TESTINSTBIN) $(TESTINSTR_DATA_FILE) AFL_FRIDA_PERSISTENT_ADDR=$(AFL_FRIDA_PERSISTENT_ADDR) \ AFL_FRIDA_PERSISTENT_RET=$(AFL_FRIDA_PERSISTENT_RET) \ - AFL_FRIDA_PERSISTENT_RETADDR_OFFSET=$(AFL_FRIDA_PERSISTENT_RETADDR_OFFSET) \ AFL_DEBUG_CHILD=1 \ LD_PRELOAD=$(ROOT)afl-frida-trace.so \ $(TESTINSTBIN) $(TESTINSTR_DATA_FILE) diff --git a/include/envs.h b/include/envs.h index 15116fc1..ea912a25 100644 --- a/include/envs.h +++ b/include/envs.h @@ -67,7 +67,6 @@ static char *afl_environment_variables[] = { "AFL_FRIDA_PERSISTENT_DEBUG", "AFL_FRIDA_PERSISTENT_HOOK", "AFL_FRIDA_PERSISTENT_RET", - "AFL_FRIDA_PERSISTENT_RETADDR_OFFSET", "AFL_FRIDA_STATS_FILE", "AFL_FRIDA_STATS_INTERVAL", "AFL_FRIDA_STATS_TRANSITIONS", |