diff options
Diffstat (limited to 'frida_mode/src/persistent')
| -rw-r--r-- | frida_mode/src/persistent/persistent.c | 97 | ||||
| -rw-r--r-- | frida_mode/src/persistent/persistent_arm32.c | 79 | ||||
| -rw-r--r-- | frida_mode/src/persistent/persistent_arm64.c | 122 | ||||
| -rw-r--r-- | frida_mode/src/persistent/persistent_x64.c | 326 | ||||
| -rw-r--r-- | frida_mode/src/persistent/persistent_x86.c | 267 |
5 files changed, 891 insertions, 0 deletions
diff --git a/frida_mode/src/persistent/persistent.c b/frida_mode/src/persistent/persistent.c new file mode 100644 index 00000000..2ec5b9cc --- /dev/null +++ b/frida_mode/src/persistent/persistent.c @@ -0,0 +1,97 @@ +#include <dlfcn.h> + +#include "frida-gum.h" + +#include "config.h" +#include "debug.h" + +#include "persistent.h" +#include "util.h" + +int __afl_sharedmem_fuzzing = 0; +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) { + + char *hook_name = getenv("AFL_FRIDA_PERSISTENT_HOOK"); + + 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; } + + if (persistent_count != 0 && persistent_start == 0) { + + FATAL( + "AFL_FRIDA_PERSISTENT_ADDR must be specified if " + "AFL_FRIDA_PERSISTENT_CNT is"); + + } + + if (persistent_ret != 0 && persistent_start == 0) { + + FATAL( + "AFL_FRIDA_PERSISTENT_ADDR must be specified if " + "AFL_FRIDA_PERSISTENT_RET is"); + + } + + 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) + WARNF("Persistent count out of recommended range (<100)"); + + if (persistent_start != 0 && !persistent_is_supported()) + FATAL("Persistent mode not supported on this architecture"); + + OKF("Instrumentation - persistent mode [%c] (0x%016" G_GINT64_MODIFIER "X)", + persistent_start == 0 ? ' ' : 'X', persistent_start); + OKF("Instrumentation - persistent count [%c] (%" G_GINT64_MODIFIER "d)", + persistent_start == 0 ? ' ' : 'X', persistent_count); + OKF("Instrumentation - hook [%s]", hook_name); + + 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) { + + void *hook_obj = dlopen(hook_name, RTLD_NOW); + if (hook_obj == NULL) + FATAL("Failed to load AFL_FRIDA_PERSISTENT_HOOK (%s)", hook_name); + + int (*afl_persistent_hook_init_ptr)(void) = + dlsym(hook_obj, "afl_persistent_hook_init"); + if (afl_persistent_hook_init_ptr == NULL) + FATAL("Failed to find afl_persistent_hook_init in %s", hook_name); + + if (afl_persistent_hook_init_ptr() == 0) + FATAL("afl_persistent_hook_init returned a failure"); + + hook = (afl_persistent_hook_fn)dlsym(hook_obj, "afl_persistent_hook"); + if (hook == NULL) + FATAL("Failed to find afl_persistent_hook in %s", hook_name); + + __afl_sharedmem_fuzzing = 1; + + } + +} + diff --git a/frida_mode/src/persistent/persistent_arm32.c b/frida_mode/src/persistent/persistent_arm32.c new file mode 100644 index 00000000..6a3c06fa --- /dev/null +++ b/frida_mode/src/persistent/persistent_arm32.c @@ -0,0 +1,79 @@ +#include "frida-gum.h" + +#include "debug.h" + +#include "persistent.h" +#include "util.h" + +#if defined(__arm__) + +struct arm_regs { + + uint32_t r0, r1, r2, r3, r4, r5, r6, r7, r8, r9, r10; + + union { + + uint32_t r11; + uint32_t fp; + + }; + + union { + + uint32_t r12; + uint32_t ip; + + }; + + union { + + uint32_t r13; + uint32_t sp; + + }; + + union { + + uint32_t r14; + uint32_t lr; + + }; + + union { + + uint32_t r15; + uint32_t pc; + + }; + + uint32_t cpsr; + + uint8_t vfp_zregs[32][16]; + uint32_t vfp_xregs[16]; + +}; + +typedef struct arm_regs arch_api_regs; + +gboolean persistent_is_supported(void) { + + return false; + +} + +void persistent_prologue(GumStalkerOutput *output) { + + UNUSED_PARAMETER(output); + FATAL("Persistent mode not supported on this architecture"); + +} + +void persistent_epilogue(GumStalkerOutput *output) { + + UNUSED_PARAMETER(output); + FATAL("Persistent mode not supported on this architecture"); + +} + +#endif + diff --git a/frida_mode/src/persistent/persistent_arm64.c b/frida_mode/src/persistent/persistent_arm64.c new file mode 100644 index 00000000..1215d8da --- /dev/null +++ b/frida_mode/src/persistent/persistent_arm64.c @@ -0,0 +1,122 @@ +#include "frida-gum.h" + +#include "config.h" +#include "debug.h" + +#include "instrument.h" +#include "util.h" + +#if defined(__aarch64__) + +struct arm64_regs { + + uint64_t x0, x1, x2, x3, x4, x5, x6, x7, x8, x9, x10; + + union { + + uint64_t x11; + uint32_t fp_32; + + }; + + union { + + uint64_t x12; + uint32_t ip_32; + + }; + + union { + + uint64_t x13; + uint32_t sp_32; + + }; + + union { + + uint64_t x14; + uint32_t lr_32; + + }; + + union { + + uint64_t x15; + uint32_t pc_32; + + }; + + union { + + uint64_t x16; + uint64_t ip0; + + }; + + union { + + uint64_t x17; + uint64_t ip1; + + }; + + uint64_t x18, x19, x20, x21, x22, x23, x24, x25, x26, x27, x28; + + union { + + uint64_t x29; + uint64_t fp; + + }; + + union { + + uint64_t x30; + uint64_t lr; + + }; + + union { + + uint64_t x31; + uint64_t sp; + + }; + + // the zero register is not saved here ofc + + uint64_t pc; + + uint32_t cpsr; + + uint8_t vfp_zregs[32][16 * 16]; + uint8_t vfp_pregs[17][32]; + uint32_t vfp_xregs[16]; + +}; + +typedef struct arm64_regs arch_api_regs; + +gboolean persistent_is_supported(void) { + + return false; + +} + +void persistent_prologue(GumStalkerOutput *output) { + + UNUSED_PARAMETER(output); + FATAL("Persistent mode not supported on this architecture"); + +} + +void persistent_epilogue(GumStalkerOutput *output) { + + UNUSED_PARAMETER(output); + FATAL("Persistent mode not supported on this architecture"); + +} + +#endif + diff --git a/frida_mode/src/persistent/persistent_x64.c b/frida_mode/src/persistent/persistent_x64.c new file mode 100644 index 00000000..4cb960fc --- /dev/null +++ b/frida_mode/src/persistent/persistent_x64.c @@ -0,0 +1,326 @@ +#include <unistd.h> +#include "frida-gum.h" + +#include "config.h" +#include "debug.h" + +#include "instrument.h" +#include "persistent.h" +#include "util.h" + +#if defined(__x86_64__) + +struct x86_64_regs { + + uint64_t rax, rbx, rcx, rdx, rdi, rsi, rbp, r8, r9, r10, r11, r12, r13, r14, + r15; + + union { + + uint64_t rip; + uint64_t pc; + + }; + + union { + + uint64_t rsp; + uint64_t sp; + + }; + + union { + + uint64_t rflags; + uint64_t flags; + + }; + + uint8_t zmm_regs[32][64]; + +}; + +typedef struct x86_64_regs arch_api_regs; + +static arch_api_regs saved_regs = {0}; + +gboolean persistent_is_supported(void) { + + return true; + +} + +static void instrument_persitent_save_regs(GumX86Writer * cw, + struct x86_64_regs *regs) { + + GumAddress regs_address = GUM_ADDRESS(regs); + gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_RSP, GUM_REG_RSP, + -(GUM_RED_ZONE_SIZE)); + + /* Should be pushing FPU here, but meh */ + gum_x86_writer_put_pushfx(cw); + gum_x86_writer_put_push_reg(cw, GUM_REG_RAX); + + gum_x86_writer_put_mov_reg_address(cw, GUM_REG_RAX, regs_address); + + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_RAX, (0x8 * 1), + GUM_REG_RBX); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_RAX, (0x8 * 2), + GUM_REG_RCX); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_RAX, (0x8 * 3), + GUM_REG_RDX); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_RAX, (0x8 * 4), + GUM_REG_RDI); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_RAX, (0x8 * 5), + GUM_REG_RSI); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_RAX, (0x8 * 6), + GUM_REG_RBP); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_RAX, (0x8 * 7), + GUM_REG_R8); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_RAX, (0x8 * 8), + GUM_REG_R9); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_RAX, (0x8 * 9), + GUM_REG_R10); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_RAX, (0x8 * 10), + GUM_REG_R11); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_RAX, (0x8 * 11), + GUM_REG_R12); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_RAX, (0x8 * 12), + GUM_REG_R13); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_RAX, (0x8 * 13), + GUM_REG_R14); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_RAX, (0x8 * 14), + GUM_REG_R15); + + /* Store RIP */ + gum_x86_writer_put_mov_reg_address(cw, GUM_REG_RBX, + GUM_ADDRESS(persistent_start)); + + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_RAX, (0x8 * 15), + GUM_REG_RBX); + + /* Store adjusted RSP */ + gum_x86_writer_put_mov_reg_reg(cw, GUM_REG_RBX, GUM_REG_RSP); + + /* RED_ZONE + Saved flags, RAX, alignment */ + gum_x86_writer_put_add_reg_imm(cw, GUM_REG_RBX, + GUM_RED_ZONE_SIZE + (0x8 * 3)); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_RAX, (0x8 * 16), + GUM_REG_RBX); + + /* Save the flags */ + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_RBX, GUM_REG_RSP, 0x8); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_RAX, (0x8 * 17), + GUM_REG_RBX); + + /* Save the RAX */ + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_RBX, GUM_REG_RSP, 0x0); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_RAX, (0x8 * 0), + GUM_REG_RBX); + + /* Pop the saved values */ + gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_RSP, GUM_REG_RSP, 0x10); + + gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_RSP, GUM_REG_RSP, + (GUM_RED_ZONE_SIZE)); + +} + +static void instrument_persitent_restore_regs(GumX86Writer * cw, + struct x86_64_regs *regs) { + + GumAddress regs_address = GUM_ADDRESS(regs); + gum_x86_writer_put_mov_reg_address(cw, GUM_REG_RAX, regs_address); + + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_RCX, GUM_REG_RAX, + (0x8 * 2)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_RDX, GUM_REG_RAX, + (0x8 * 3)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_RDI, GUM_REG_RAX, + (0x8 * 4)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_RSI, GUM_REG_RAX, + (0x8 * 5)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_RBP, GUM_REG_RAX, + (0x8 * 6)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_R8, GUM_REG_RAX, + (0x8 * 7)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_R9, GUM_REG_RAX, + (0x8 * 8)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_R10, GUM_REG_RAX, + (0x8 * 9)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_R11, GUM_REG_RAX, + (0x8 * 10)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_R12, GUM_REG_RAX, + (0x8 * 11)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_R13, GUM_REG_RAX, + (0x8 * 12)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_R14, GUM_REG_RAX, + (0x8 * 13)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_R15, GUM_REG_RAX, + (0x8 * 14)); + + /* Don't restore RIP or RSP */ + + /* Restore RBX, RAX & Flags */ + gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_RSP, GUM_REG_RSP, + -(GUM_RED_ZONE_SIZE)); + + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_RBX, GUM_REG_RAX, + (0x8 * 1)); + gum_x86_writer_put_push_reg(cw, GUM_REG_RBX); + + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_RBX, GUM_REG_RAX, + (0x8 * 0)); + gum_x86_writer_put_push_reg(cw, GUM_REG_RBX); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_RBX, GUM_REG_RAX, + (0x8 * 17)); + gum_x86_writer_put_push_reg(cw, GUM_REG_RBX); + + gum_x86_writer_put_popfx(cw); + gum_x86_writer_put_pop_reg(cw, GUM_REG_RAX); + gum_x86_writer_put_pop_reg(cw, GUM_REG_RBX); + + gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_RSP, GUM_REG_RSP, + (GUM_RED_ZONE_SIZE)); + +} + +static void instrument_exit(GumX86Writer *cw) { + + gum_x86_writer_put_mov_reg_address(cw, GUM_REG_RAX, GUM_ADDRESS(_exit)); + gum_x86_writer_put_mov_reg_u32(cw, GUM_REG_RDI, 0); + gum_x86_writer_put_call_reg(cw, GUM_REG_RAX); + +} + +static int instrument_afl_persistent_loop_func(void) { + + int ret = __afl_persistent_loop(persistent_count); + previous_pc = 0; + return ret; + +} + +static void instrument_afl_persistent_loop(GumX86Writer *cw) { + + gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_RSP, GUM_REG_RSP, + -(GUM_RED_ZONE_SIZE)); + gum_x86_writer_put_call_address_with_arguments( + cw, GUM_CALL_CAPI, GUM_ADDRESS(instrument_afl_persistent_loop_func), 0); + gum_x86_writer_put_test_reg_reg(cw, GUM_REG_RAX, GUM_REG_RAX); + + gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_RSP, GUM_REG_RSP, + (GUM_RED_ZONE_SIZE)); + +} + +static void persistent_prologue_hook(GumX86Writer * cw, + struct x86_64_regs *regs) { + + if (hook == NULL) return; + gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_RSP, GUM_REG_RSP, + -(GUM_RED_ZONE_SIZE)); + + gum_x86_writer_put_mov_reg_address(cw, GUM_REG_RCX, + GUM_ADDRESS(&__afl_fuzz_len)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_RCX, GUM_REG_RCX, 0); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_RCX, GUM_REG_RCX, 0); + gum_x86_writer_put_mov_reg_u64(cw, GUM_REG_RDI, 0xffffffff); + gum_x86_writer_put_and_reg_reg(cw, GUM_REG_RCX, GUM_REG_RDI); + + gum_x86_writer_put_mov_reg_address(cw, GUM_REG_RDX, + GUM_ADDRESS(&__afl_fuzz_ptr)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_RDX, GUM_REG_RDX, 0); + + gum_x86_writer_put_call_address_with_arguments( + cw, GUM_CALL_CAPI, GUM_ADDRESS(hook), 4, GUM_ARG_ADDRESS, + GUM_ADDRESS(regs), GUM_ARG_ADDRESS, GUM_ADDRESS(0), GUM_ARG_REGISTER, + GUM_REG_RDX, GUM_ARG_REGISTER, GUM_REG_RCX); + + gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_RSP, GUM_REG_RSP, + (GUM_RED_ZONE_SIZE)); + +} + +void persistent_prologue(GumStalkerOutput *output) { + + /* + * SAVE REGS + * SAVE RET + * POP RET + * loop: + * CALL instrument_afl_persistent_loop + * TEST EAX, EAX + * JZ end: + * call hook (optionally) + * RESTORE REGS + * call original + * jmp loop: + * + * end: + * JMP SAVED RET + * + * original: + * INSTRUMENTED PERSISTENT FUNC + */ + + GumX86Writer *cw = output->writer.x86; + + 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)); + + /* loop: */ + gum_x86_writer_put_label(cw, loop); + + /* call instrument_prologue_func */ + instrument_afl_persistent_loop(cw); + + /* jz done */ + gconstpointer done = cw->code + 1; + gum_x86_writer_put_jcc_near_label(cw, X86_INS_JE, done, GUM_UNLIKELY); + + /* Optionally call the persistent hook */ + persistent_prologue_hook(cw, &saved_regs); + + instrument_persitent_restore_regs(cw, &saved_regs); + gconstpointer original = cw->code + 1; + /* call original */ + + gum_x86_writer_put_call_near_label(cw, original); + + /* jmp loop */ + gum_x86_writer_put_jmp_near_label(cw, loop); + + /* done: */ + gum_x86_writer_put_label(cw, done); + + instrument_exit(cw); + + /* original: */ + gum_x86_writer_put_label(cw, original); + + if (persistent_debug) { gum_x86_writer_put_breakpoint(cw); } + + gum_x86_writer_flush(cw); + +} + +void persistent_epilogue(GumStalkerOutput *output) { + + GumX86Writer *cw = output->writer.x86; + + 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); + +} + +#endif + diff --git a/frida_mode/src/persistent/persistent_x86.c b/frida_mode/src/persistent/persistent_x86.c new file mode 100644 index 00000000..b30dfadf --- /dev/null +++ b/frida_mode/src/persistent/persistent_x86.c @@ -0,0 +1,267 @@ +#include "frida-gum.h" + +#include "config.h" + +#include "instrument.h" +#include "persistent.h" + +#if defined(__i386__) + +struct x86_regs { + + uint32_t eax, ebx, ecx, edx, edi, esi, ebp; + + union { + + uint32_t eip; + uint32_t pc; + + }; + + union { + + uint32_t esp; + uint32_t sp; + + }; + + union { + + uint32_t eflags; + uint32_t flags; + + }; + + uint8_t xmm_regs[8][16]; + +}; + +typedef struct x86_regs arch_api_regs; + +static arch_api_regs saved_regs = {0}; + +gboolean persistent_is_supported(void) { + + return true; + +} + +static void instrument_persitent_save_regs(GumX86Writer * cw, + struct x86_regs *regs) { + + GumAddress regs_address = GUM_ADDRESS(regs); + + /* Should be pushing FPU here, but meh */ + gum_x86_writer_put_pushfx(cw); + gum_x86_writer_put_push_reg(cw, GUM_REG_EAX); + + gum_x86_writer_put_mov_reg_address(cw, GUM_REG_EAX, regs_address); + + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_EAX, (0x4 * 1), + GUM_REG_EBX); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_EAX, (0x4 * 2), + GUM_REG_ECX); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_EAX, (0x4 * 3), + GUM_REG_EDX); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_EAX, (0x4 * 4), + GUM_REG_EDI); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_EAX, (0x4 * 5), + GUM_REG_ESI); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_EAX, (0x4 * 6), + GUM_REG_EBP); + + /* Store RIP */ + gum_x86_writer_put_mov_reg_address(cw, GUM_REG_EBX, + GUM_ADDRESS(persistent_start)); + + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_EAX, (0x4 * 7), + GUM_REG_EBX); + + /* Store adjusted RSP */ + gum_x86_writer_put_mov_reg_reg(cw, GUM_REG_EBX, GUM_REG_ESP); + + /* RED_ZONE + Saved flags, RAX */ + gum_x86_writer_put_add_reg_imm(cw, GUM_REG_EBX, (0x4 * 2)); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_EAX, (0x4 * 8), + GUM_REG_EBX); + + /* Save the flags */ + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_EBX, GUM_REG_ESP, 0x4); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_EAX, (0x4 * 9), + GUM_REG_EBX); + + /* Save the RAX */ + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_EBX, GUM_REG_ESP, 0x0); + gum_x86_writer_put_mov_reg_offset_ptr_reg(cw, GUM_REG_EAX, (0x4 * 0), + GUM_REG_EBX); + + /* Pop the saved values */ + gum_x86_writer_put_lea_reg_reg_offset(cw, GUM_REG_ESP, GUM_REG_ESP, 0x8); + +} + +static void instrument_persitent_restore_regs(GumX86Writer * cw, + struct x86_regs *regs) { + + GumAddress regs_address = GUM_ADDRESS(regs); + gum_x86_writer_put_mov_reg_address(cw, GUM_REG_EAX, regs_address); + + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_ECX, GUM_REG_EAX, + (0x4 * 2)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_EDX, GUM_REG_EAX, + (0x4 * 3)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_EDI, GUM_REG_EAX, + (0x4 * 4)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_ESI, GUM_REG_EAX, + (0x4 * 5)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_EBP, GUM_REG_EAX, + (0x4 * 6)); + + /* Don't restore RIP or RSP */ + + /* Restore RBX, RAX & Flags */ + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_EBX, GUM_REG_EAX, + (0x4 * 1)); + gum_x86_writer_put_push_reg(cw, GUM_REG_EBX); + + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_EBX, GUM_REG_EAX, + (0x4 * 0)); + gum_x86_writer_put_push_reg(cw, GUM_REG_EBX); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_EBX, GUM_REG_EAX, + (0x4 * 9)); + gum_x86_writer_put_push_reg(cw, GUM_REG_EBX); + + gum_x86_writer_put_popfx(cw); + gum_x86_writer_put_pop_reg(cw, GUM_REG_EAX); + gum_x86_writer_put_pop_reg(cw, GUM_REG_EBX); + +} + +static void instrument_exit(GumX86Writer *cw) { + + gum_x86_writer_put_mov_reg_address(cw, GUM_REG_EAX, GUM_ADDRESS(_exit)); + gum_x86_writer_put_mov_reg_u32(cw, GUM_REG_EDI, 0); + gum_x86_writer_put_push_reg(cw, GUM_REG_EDI); + gum_x86_writer_put_call_reg(cw, GUM_REG_EAX); + +} + +static int instrument_afl_persistent_loop_func(void) { + + int ret = __afl_persistent_loop(persistent_count); + previous_pc = 0; + return ret; + +} + +static void instrument_afl_persistent_loop(GumX86Writer *cw) { + + gum_x86_writer_put_call_address_with_arguments( + cw, GUM_CALL_CAPI, GUM_ADDRESS(instrument_afl_persistent_loop_func), 0); + gum_x86_writer_put_test_reg_reg(cw, GUM_REG_EAX, GUM_REG_EAX); + +} + +static void persistent_prologue_hook(GumX86Writer *cw, struct x86_regs *regs) { + + if (hook == NULL) return; + + gum_x86_writer_put_mov_reg_address(cw, GUM_REG_ECX, + GUM_ADDRESS(&__afl_fuzz_len)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_ECX, GUM_REG_ECX, 0); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_ECX, GUM_REG_ECX, 0); + + gum_x86_writer_put_mov_reg_address(cw, GUM_REG_EDX, + GUM_ADDRESS(&__afl_fuzz_ptr)); + gum_x86_writer_put_mov_reg_reg_offset_ptr(cw, GUM_REG_EDX, GUM_REG_EDX, 0); + + /* Base address is 64-bits (hence two zero arguments) */ + gum_x86_writer_put_call_address_with_arguments( + cw, GUM_CALL_CAPI, GUM_ADDRESS(hook), 5, GUM_ARG_ADDRESS, + GUM_ADDRESS(regs), GUM_ARG_ADDRESS, GUM_ADDRESS(0), GUM_ARG_ADDRESS, + GUM_ADDRESS(0), GUM_ARG_REGISTER, GUM_REG_EDX, GUM_ARG_REGISTER, + GUM_REG_ECX); + +} + +void persistent_prologue(GumStalkerOutput *output) { + + /* + * SAVE REGS + * SAVE RET + * POP RET + * loop: + * CALL instrument_afl_persistent_loop + * TEST EAX, EAX + * JZ end: + * call hook (optionally) + * RESTORE REGS + * call original + * jmp loop: + * + * end: + * JMP SAVED RET + * + * original: + * INSTRUMENTED PERSISTENT FUNC + */ + + GumX86Writer *cw = output->writer.x86; + + 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)); + + /* loop: */ + gum_x86_writer_put_label(cw, loop); + + /* call instrument_prologue_func */ + instrument_afl_persistent_loop(cw); + + /* jz done */ + gconstpointer done = cw->code + 1; + gum_x86_writer_put_jcc_near_label(cw, X86_INS_JE, done, GUM_UNLIKELY); + + /* Optionally call the persistent hook */ + persistent_prologue_hook(cw, &saved_regs); + + instrument_persitent_restore_regs(cw, &saved_regs); + gconstpointer original = cw->code + 1; + /* call original */ + gum_x86_writer_put_call_near_label(cw, original); + /* jmp loop */ + gum_x86_writer_put_jmp_near_label(cw, loop); + + /* done: */ + gum_x86_writer_put_label(cw, done); + + instrument_exit(cw); + + /* original: */ + gum_x86_writer_put_label(cw, original); + + if (persistent_debug) { gum_x86_writer_put_breakpoint(cw); } + + gum_x86_writer_flush(cw); + +} + +void persistent_epilogue(GumStalkerOutput *output) { + + GumX86Writer *cw = output->writer.x86; + + 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); + +} + +#endif + |