Mach/Inject.cpp

   1 #include <dlfcn.h>
   2 #include <mach/mach.h>
   3
   4 extern "C" {
   5 #include <mach-o/nlist.h>
   6 }
   7
   8 #include <cstdio>
   9 #include <pthread.h>
  10
  11 #include "Baton.hpp"
  12 #include "Exception.hpp"
  13 #include "Pooling.hpp"
  14 #include "Trampoline.t.hpp"
  15
  16 extern "C" void _pthread_set_self(pthread_t);
  17
  18 template <typename Type_>
  19 static void nlset(Type_ &function, struct nlist *nl, size_t index) {
  20     struct nlist &name(nl[index]);
  21     uintptr_t value(name.n_value);
  22     if ((name.n_desc & N_ARM_THUMB_DEF) != 0)
  23         value |= 0x00000001;
  24     function = reinterpret_cast<Type_>(value);
  25 }
  26
  27 void InjectLibrary(pid_t pid) {
  28     const char *library("/Library/MobileSubstrate/DynamicLibraries/Cycript.dylib");
  29
  30     static const size_t Stack_(8 * 1024);
  31     size_t length(strlen(library) + 1), depth(sizeof(Baton) + length);
  32     depth = (depth + sizeof(uintptr_t) + 1) / sizeof(uintptr_t) * sizeof(uintptr_t);
  33
  34     CYPool pool;
  35     uint8_t *local(reinterpret_cast<uint8_t *>(apr_palloc(pool, depth)));
  36
  37     Baton *baton(reinterpret_cast<Baton *>(local));
  38     baton->pthread_create = &pthread_create;
  39     baton->pthread_detach = &pthread_detach;
  40     baton->dlopen = &dlopen;
  41     baton->mach_thread_self = &mach_thread_self;
  42     baton->thread_terminate = &thread_terminate;
  43     memcpy(baton->library, library, length);
  44
  45     struct nlist nl[2];
  46     memset(nl, 0, sizeof(nl));
  47     nl[0].n_un.n_name = (char *) "__pthread_set_self";
  48     nlist("/usr/lib/libSystem.B.dylib", nl);
  49     nlset(baton->_pthread_set_self, nl, 0);
  50
  51     vm_size_t size(depth + Stack_);
  52
  53     mach_port_t self(mach_task_self()), task;
  54     _krncall(task_for_pid(self, pid, &task));
  55
  56     vm_address_t data;
  57     _krncall(vm_allocate(task, &data, size, true));
  58     vm_address_t stack(data + depth);
  59     vm_write(task, data, reinterpret_cast<vm_address_t>(baton), depth);
  60
  61     vm_address_t code;
  62     _krncall(vm_allocate(task, &code, sizeof(Trampoline_), true));
  63     vm_write(task, code, reinterpret_cast<vm_address_t>(Trampoline_), sizeof(Trampoline_));
  64     _krncall(vm_protect(task, code, sizeof(Trampoline_), false, VM_PROT_READ | VM_PROT_EXECUTE));
  65
  66     thread_act_t thread;
  67     _krncall(thread_create(task, &thread));
  68
  69     thread_state_flavor_t flavor;
  70     mach_msg_type_number_t count;
  71
  72 #if defined(__arm__)
  73     arm_thread_state_t state;
  74     memset(&state, 0, sizeof(state));
  75
  76     flavor = ARM_THREAD_STATE;
  77     count = ARM_THREAD_STATE_COUNT;
  78
  79     _krncall(thread_get_state(thread, flavor, reinterpret_cast<thread_state_t>(&state), &count));
  80     _assert(count == ARM_THREAD_STATE_COUNT);
  81
  82     state.r[0] = data;
  83     state.r[1] = RTLD_LAZY | RTLD_GLOBAL;
  84     state.sp = stack + Stack_;
  85     state.pc = code;
  86
  87     if ((state.pc & 0x1) != 0) {
  88         state.pc &= ~0x1;
  89         state.cpsr |= 0x20;
  90     }
  91
  92     _krncall(thread_set_state(thread, flavor, reinterpret_cast<thread_state_t>(&state), count));
  93 #else
  94     #error XXX: implement
  95 #endif
  96
  97     _krncall(thread_resume(thread));
  98
  99     //_krncall(thread_create_running(task, flavor, reinterpret_cast<thread_state_t>(&state), count, &thread));
 100
 101     //_krncall(mach_port_deallocate(self, task));
 102 }