1 files changed, 93 insertions, 0 deletions
diff --git a/frida_mode/src/asan/asan_x86.c b/frida_mode/src/asan/asan_x86.c
new file mode 100644
index 00000000..8490b490
--- /dev/null
+++ b/frida_mode/src/asan/asan_x86.c
@@ -0,0 +1,93 @@
+#include <dlfcn.h>
+#include "frida-gum.h"
+
+#include "debug.h"
+
+#include "asan.h"
+#include "ctx.h"
+#include "util.h"
+
+#if defined(__i386__)
+
+typedef void (*asan_loadN_t)(gsize address, uint8_t size);
+typedef void (*asan_storeN_t)(gsize address, uint8_t size);
+
+asan_loadN_t  asan_loadN = NULL;
+asan_storeN_t asan_storeN = NULL;
+
+static void asan_callout(GumCpuContext *ctx, gpointer user_data) {
+
+  UNUSED_PARAMETER(user_data);
+
+  cs_x86_op * operand = (cs_x86_op *)user_data;
+  x86_op_mem *mem = &operand->mem;
+  gsize       base = 0;
+  gsize       index = 0;
+  gsize       address;
+  uint8_t     size;
+
+  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 + (mem->scale * index) + mem->disp;
+  size = operand->size;
+
+  if (operand->access == CS_AC_READ) {
+
+    asan_loadN(address, size);
+
+  } else if (operand->access == CS_AC_WRITE) {
+
+    asan_storeN(address, size);
+
+  }
+
+}
+
+void asan_instrument(const cs_insn *instr, GumStalkerIterator *iterator) {
+
+  UNUSED_PARAMETER(iterator);
+
+  cs_x86      x86 = instr->detail->x86;
+  cs_x86_op * operand;
+  x86_op_mem *mem;
+  cs_x86_op * ctx;
+
+  if (!asan_initialized) return;
+
+  if (instr->id == X86_INS_LEA) return;
+
+  if (instr->id == X86_INS_NOP) return;
+
+  for (uint8_t i = 0; i < x86.op_count; i++) {
+
+    operand = &x86.operands[i];
+
+    if (operand->type != X86_OP_MEM) { continue; }
+
+    mem = &operand->mem;
+    if (mem->segment != X86_REG_INVALID) { continue; }
+
+    ctx = g_malloc0(sizeof(cs_x86_op));
+    memcpy(ctx, operand, sizeof(cs_x86_op));
+    gum_stalker_iterator_put_callout(iterator, asan_callout, ctx, g_free);
+
+  }
+
+}
+
+void asan_arch_init(void) {
+
+  asan_loadN = (asan_loadN_t)dlsym(RTLD_DEFAULT, "__asan_loadN");
+  asan_storeN = (asan_loadN_t)dlsym(RTLD_DEFAULT, "__asan_storeN");
+  if (asan_loadN == NULL || asan_storeN == NULL) {
+
+    FATAL("Frida ASAN failed to find '__asan_loadN' or '__asan_storeN'");
+
+  }
+
+}
+
+#endif
+