diff options
Diffstat (limited to 'frida_mode/src/cmplog/cmplog_x86.c')
| -rw-r--r-- | frida_mode/src/cmplog/cmplog_x86.c | 277 |
1 files changed, 277 insertions, 0 deletions
diff --git a/frida_mode/src/cmplog/cmplog_x86.c b/frida_mode/src/cmplog/cmplog_x86.c new file mode 100644 index 00000000..a27df0af --- /dev/null +++ b/frida_mode/src/cmplog/cmplog_x86.c @@ -0,0 +1,277 @@ +#include "frida-gum.h" + +#include "debug.h" +#include "cmplog.h" + +#include "ctx.h" +#include "frida_cmplog.h" +#include "util.h" + +#if defined(__i386__) + +typedef struct { + + x86_op_type type; + uint8_t size; + + union { + + x86_op_mem mem; + x86_reg reg; + int64_t imm; + + }; + +} cmplog_ctx_t; + +typedef struct { + + cmplog_ctx_t operand1; + cmplog_ctx_t operand2; + +} cmplog_pair_ctx_t; + +static gboolean cmplog_read_mem(GumCpuContext *ctx, uint8_t size, + x86_op_mem *mem, gsize *val) { + + gsize base = 0; + gsize index = 0; + gsize address; + + if (mem->base != X86_REG_INVALID) base = ctx_read_reg(ctx, mem->base); + + if (mem->index != X86_REG_INVALID) index = ctx_read_reg(ctx, mem->index); + + address = base + (index * mem->scale) + mem->disp; + + if (!cmplog_is_readable(address, size)) { return FALSE; } + + switch (size) { + + case 1: + *val = *((guint8 *)GSIZE_TO_POINTER(address)); + return TRUE; + case 2: + *val = *((guint16 *)GSIZE_TO_POINTER(address)); + return TRUE; + case 4: + *val = *((guint32 *)GSIZE_TO_POINTER(address)); + return TRUE; + default: + FATAL("Invalid operand size: %d\n", size); + + } + + return FALSE; + +} + +static gboolean cmplog_get_operand_value(GumCpuContext *context, + cmplog_ctx_t *ctx, gsize *val) { + + switch (ctx->type) { + + case X86_OP_REG: + *val = ctx_read_reg(context, ctx->reg); + return TRUE; + case X86_OP_IMM: + *val = ctx->imm; + return TRUE; + case X86_OP_MEM: + return cmplog_read_mem(context, ctx->size, &ctx->mem, val); + default: + FATAL("Invalid operand type: %d\n", ctx->type); + + } + + return FALSE; + +} + +static void cmplog_call_callout(GumCpuContext *context, gpointer user_data) { + + UNUSED_PARAMETER(user_data); + + gsize address = ctx_read_reg(context, X86_REG_EIP); + gsize *esp = (gsize *)ctx_read_reg(context, X86_REG_ESP); + + if (!cmplog_is_readable(GPOINTER_TO_SIZE(esp), 12)) return; + + /* + * This callout is place immediately before the call instruction, and hence + * the return address is not yet pushed on the top of the stack. + */ + gsize arg1 = esp[0]; + gsize arg2 = esp[1]; + + if (((G_MAXULONG - arg1) < 32) || ((G_MAXULONG - arg2) < 32)) return; + + if (!cmplog_is_readable(arg1, 32) || !cmplog_is_readable(arg2, 32)) return; + + void *ptr1 = GSIZE_TO_POINTER(arg1); + void *ptr2 = GSIZE_TO_POINTER(arg2); + + uintptr_t k = address; + + k = (k >> 4) ^ (k << 8); + k &= CMP_MAP_W - 1; + + __afl_cmp_map->headers[k].type = CMP_TYPE_RTN; + + u32 hits = __afl_cmp_map->headers[k].hits; + __afl_cmp_map->headers[k].hits = hits + 1; + + __afl_cmp_map->headers[k].shape = 31; + + hits &= CMP_MAP_RTN_H - 1; + gum_memcpy(((struct cmpfn_operands *)__afl_cmp_map->log[k])[hits].v0, ptr1, + 32); + gum_memcpy(((struct cmpfn_operands *)__afl_cmp_map->log[k])[hits].v1, ptr2, + 32); + +} + +static void cmplog_instrument_put_operand(cmplog_ctx_t *ctx, + cs_x86_op * operand) { + + ctx->type = operand->type; + ctx->size = operand->size; + switch (operand->type) { + + case X86_OP_REG: + gum_memcpy(&ctx->reg, &operand->reg, sizeof(x86_reg)); + break; + case X86_OP_IMM: + gum_memcpy(&ctx->imm, &operand->imm, sizeof(int64_t)); + break; + case X86_OP_MEM: + gum_memcpy(&ctx->mem, &operand->mem, sizeof(x86_op_mem)); + break; + default: + FATAL("Invalid operand type: %d\n", operand->type); + + } + +} + +static void cmplog_instrument_call(const cs_insn * instr, + GumStalkerIterator *iterator) { + + cs_x86 x86 = instr->detail->x86; + cs_x86_op *operand; + + if (instr->id != X86_INS_CALL) return; + + if (x86.op_count != 1) return; + + operand = &x86.operands[0]; + + if (operand->type == X86_OP_INVALID) return; + if (operand->type == X86_OP_MEM && operand->mem.segment != X86_REG_INVALID) + return; + + gum_stalker_iterator_put_callout(iterator, cmplog_call_callout, NULL, NULL); + +} + +static void cmplog_handle_cmp_sub(GumCpuContext *context, gsize operand1, + gsize operand2, uint8_t size) { + + gsize address = ctx_read_reg(context, X86_REG_EIP); + + register uintptr_t k = (uintptr_t)address; + + k = (k >> 4) ^ (k << 8); + k &= CMP_MAP_W - 1; + + __afl_cmp_map->headers[k].type = CMP_TYPE_INS; + + u32 hits = __afl_cmp_map->headers[k].hits; + __afl_cmp_map->headers[k].hits = hits + 1; + + __afl_cmp_map->headers[k].shape = (size - 1); + + hits &= CMP_MAP_H - 1; + __afl_cmp_map->log[k][hits].v0 = operand1; + __afl_cmp_map->log[k][hits].v1 = operand2; + +} + +static void cmplog_cmp_sub_callout(GumCpuContext *context, gpointer user_data) { + + cmplog_pair_ctx_t *ctx = (cmplog_pair_ctx_t *)user_data; + gsize operand1; + gsize operand2; + + if (ctx->operand1.size != ctx->operand2.size) FATAL("Operand size mismatch"); + + if (!cmplog_get_operand_value(context, &ctx->operand1, &operand1)) { return; } + if (!cmplog_get_operand_value(context, &ctx->operand2, &operand2)) { return; } + + cmplog_handle_cmp_sub(context, operand1, operand2, ctx->operand1.size); + +} + +static void cmplog_instrument_cmp_sub_put_callout(GumStalkerIterator *iterator, + cs_x86_op * operand1, + cs_x86_op *operand2) { + + cmplog_pair_ctx_t *ctx = g_malloc(sizeof(cmplog_pair_ctx_t)); + if (ctx == NULL) return; + + cmplog_instrument_put_operand(&ctx->operand1, operand1); + cmplog_instrument_put_operand(&ctx->operand2, operand2); + + gum_stalker_iterator_put_callout(iterator, cmplog_cmp_sub_callout, ctx, + g_free); + +} + +static void cmplog_instrument_cmp_sub(const cs_insn * instr, + GumStalkerIterator *iterator) { + + cs_x86 x86 = instr->detail->x86; + cs_x86_op *operand1; + cs_x86_op *operand2; + + switch (instr->id) { + + case X86_INS_CMP: + case X86_INS_SUB: + break; + default: + return; + + } + + if (x86.op_count != 2) return; + + operand1 = &x86.operands[0]; + operand2 = &x86.operands[1]; + + if (operand1->type == X86_OP_INVALID) return; + if (operand2->type == X86_OP_INVALID) return; + + if ((operand1->type == X86_OP_MEM) && + (operand1->mem.segment != X86_REG_INVALID)) + return; + + if ((operand2->type == X86_OP_MEM) && + (operand2->mem.segment != X86_REG_INVALID)) + return; + + cmplog_instrument_cmp_sub_put_callout(iterator, operand1, operand2); + +} + +void cmplog_instrument(const cs_insn *instr, GumStalkerIterator *iterator) { + + if (__afl_cmp_map == NULL) return; + + cmplog_instrument_call(instr, iterator); + cmplog_instrument_cmp_sub(instr, iterator); + +} + +#endif + |