Mach/Inject.cpp

   1 /* Cycript - Optimizing JavaScript Compiler/Runtime
   2  * Copyright (C) 2009-2013  Jay Freeman (saurik)
   3 */
   4
   5 /* GNU General Public License, Version 3 {{{ */
   6 /*
   7  * Cycript is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published
   9  * by the Free Software Foundation, either version 3 of the License,
  10  * or (at your option) any later version.
  11  *
  12  * Cycript is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with Cycript.  If not, see <http://www.gnu.org/licenses/>.
  19 **/
  20 /* }}} */
  21
  22 #include <dlfcn.h>
  23 #include <mach/mach.h>
  24
  25 #include <mach/machine/thread_status.h>
  26
  27 #include <cstdio>
  28 #include <pthread.h>
  29 #include <unistd.h>
  30
  31 #include "Baton.hpp"
  32 #include "Exception.hpp"
  33 #include "Pooling.hpp"
  34 #include "Trampoline.t.hpp"
  35
  36 void InjectLibrary(pid_t pid) {
  37     const char *library(CY_LIBRARY);
  38
  39     static const size_t Stack_(8 * 1024);
  40     size_t length(strlen(library) + 1), depth(sizeof(Baton) + length);
  41     depth = (depth + sizeof(uintptr_t) + 1) / sizeof(uintptr_t) * sizeof(uintptr_t);
  42
  43     CYPool pool;
  44     uint8_t *local(pool.malloc<uint8_t>(depth));
  45     Baton *baton(reinterpret_cast<Baton *>(local));
  46
  47     baton->pid = getpid();
  48     memcpy(baton->library, library, length);
  49
  50     mach_port_t self(mach_task_self()), task;
  51     _krncall(task_for_pid(self, pid, &task));
  52
  53     mach_msg_type_number_t count;
  54
  55     task_dyld_info info;
  56     count = TASK_DYLD_INFO_COUNT;
  57     _krncall(task_info(task, TASK_DYLD_INFO, reinterpret_cast<task_info_t>(&info), &count));
  58     _assert(count == TASK_DYLD_INFO_COUNT);
  59     _assert(info.all_image_info_addr != 0);
  60     baton->dyld = info.all_image_info_addr;
  61
  62     vm_size_t size(depth + Stack_);
  63     vm_address_t stack;
  64     _krncall(vm_allocate(task, &stack, size, true));
  65
  66     vm_address_t data(stack + Stack_);
  67     _krncall(vm_write(task, data, reinterpret_cast<vm_address_t>(baton), depth));
  68
  69     thread_act_t thread;
  70     _krncall(thread_create(task, &thread));
  71
  72     thread_state_flavor_t flavor;
  73 #if defined (__i386__) || defined(__x86_64__)
  74     x86_thread_state_t state;
  75     flavor = x86_THREAD_STATE;
  76     count = x86_THREAD_STATE_COUNT;
  77 #elif defined(__arm__)
  78     arm_thread_state_t state;
  79     flavor = ARM_THREAD_STATE;
  80     count = ARM_THREAD_STATE_COUNT;
  81 #else
  82     #error XXX: implement
  83 #endif
  84
  85     memset(&state, 0, sizeof(state));
  86     mach_msg_type_number_t read(count);
  87     _krncall(thread_get_state(thread, flavor, reinterpret_cast<thread_state_t>(&state), &read));
  88     _assert(read == count);
  89
  90     Trampoline *trampoline;
  91     size_t push;
  92
  93 #if defined(__i386__) || defined(__x86_64__)
  94     switch (state.tsh.flavor) {
  95         case i386_THREAD_STATE:
  96             trampoline = &Trampoline_i386_;
  97             push = 5;
  98             break;
  99         case x86_THREAD_STATE64:
 100             trampoline = &Trampoline_x86_64_;
 101             push = 2;
 102             break;
 103         default:
 104             _assert(false);
 105     }
 106 #elif defined(__arm__)
 107     trampoline = &Trampoline_armv6_;
 108     push = 0;
 109 #else
 110     #error XXX: implement
 111 #endif
 112
 113     vm_address_t code;
 114     _krncall(vm_allocate(task, &code, trampoline->size_, true));
 115     _krncall(vm_write(task, code, reinterpret_cast<vm_address_t>(trampoline->data_), trampoline->size_));
 116     _krncall(vm_protect(task, code, trampoline->size_, false, VM_PROT_READ | VM_PROT_EXECUTE));
 117
 118     uint32_t frame[push];
 119     if (sizeof(frame) != 0)
 120         memset(frame, 0, sizeof(frame));
 121
 122 #if defined(__i386__) || defined(__x86_64__)
 123     switch (state.tsh.flavor) {
 124         case i386_THREAD_STATE:
 125             frame[1] = data;
 126             state.uts.ts32.__eip = code + trampoline->entry_;
 127             state.uts.ts32.__esp = stack + Stack_ - sizeof(frame);
 128             break;
 129         case x86_THREAD_STATE64:
 130             state.uts.ts64.__rdi = data;
 131             state.uts.ts64.__rip = code + trampoline->entry_;
 132             state.uts.ts64.__rsp = stack + Stack_ - sizeof(frame);
 133             break;
 134         default:
 135             _assert(false);
 136     }
 137 #elif defined(__arm__)
 138     state.__r[0] = data;
 139     state.__pc = code + trampoline->entry_;
 140     state.__sp = stack + Stack_ - sizeof(frame);
 141
 142     if ((state.__pc & 0x1) != 0) {
 143         state.__pc &= ~0x1;
 144         state.__cpsr |= 0x20;
 145     }
 146 #else
 147     #error XXX: implement
 148 #endif
 149
 150     if (sizeof(frame) != 0)
 151         _krncall(vm_write(task, stack + Stack_ - sizeof(frame), reinterpret_cast<vm_address_t>(frame), sizeof(frame)));
 152
 153     _krncall(thread_set_state(thread, flavor, reinterpret_cast<thread_state_t>(&state), count));
 154     _krncall(thread_resume(thread));
 155
 156     _krncall(mach_port_deallocate(self, task));
 157 }