Mach/Inject.cpp

   1 /* Cycript - Optimizing JavaScript Compiler/Runtime
   2  * Copyright (C) 2009-2010  Jay Freeman (saurik)
   3 */
   4
   5 /* GNU Lesser General Public License, Version 3 {{{ */
   6 /*
   7  * Cycript is free software: you can redistribute it and/or modify it under
   8  * the terms of the GNU Lesser General Public License as published by the
   9  * Free Software Foundation, either version 3 of the License, or (at your
  10  * option) any later version.
  11  *
  12  * Cycript is distributed in the hope that it will be useful, but WITHOUT
  13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
  15  * License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser 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/i386/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 extern "C" void __pthread_set_self(pthread_t);
  37
  38 void InjectLibrary(pid_t pid) {
  39     const char *library(CY_LIBRARY);
  40
  41     static const size_t Stack_(8 * 1024);
  42     size_t length(strlen(library) + 1), depth(sizeof(Baton) + length);
  43     depth = (depth + sizeof(uintptr_t) + 1) / sizeof(uintptr_t) * sizeof(uintptr_t);
  44
  45     CYPool pool;
  46     uint8_t *local(reinterpret_cast<uint8_t *>(apr_palloc(pool, depth)));
  47     Baton *baton(reinterpret_cast<Baton *>(local));
  48
  49     baton->__pthread_set_self = &__pthread_set_self;
  50
  51     baton->dlerror = &dlerror;
  52     baton->dlsym = &dlsym;
  53
  54     baton->pid = getpid();
  55     memcpy(baton->library, library, length);
  56
  57     vm_size_t size(depth + Stack_);
  58
  59     mach_port_t self(mach_task_self()), task;
  60     _krncall(task_for_pid(self, pid, &task));
  61
  62     vm_address_t stack;
  63     _krncall(vm_allocate(task, &stack, size, true));
  64     vm_address_t data(stack + Stack_);
  65
  66     vm_write(task, data, reinterpret_cast<vm_address_t>(baton), depth);
  67
  68     thread_act_t thread;
  69     _krncall(thread_create(task, &thread));
  70
  71     thread_state_flavor_t flavor;
  72     mach_msg_type_number_t count;
  73     size_t push;
  74
  75     Trampoline *trampoline;
  76
  77 #if defined(__arm__)
  78     trampoline = &Trampoline_arm_;
  79     arm_thread_state_t state;
  80     flavor = ARM_THREAD_STATE;
  81     count = ARM_THREAD_STATE_COUNT;
  82     push = 0;
  83 #elif defined(__i386__)
  84     trampoline = &Trampoline_i386_;
  85     i386_thread_state_t state;
  86     flavor = i386_THREAD_STATE;
  87     count = i386_THREAD_STATE_COUNT;
  88     push = 5;
  89 #elif defined(__x86_64__)
  90     trampoline = &Trampoline_x86_64_;
  91     x86_thread_state64_t state;
  92     flavor = x86_THREAD_STATE64;
  93     count = x86_THREAD_STATE64_COUNT;
  94     push = 2;
  95 #else
  96     #error XXX: implement
  97 #endif
  98
  99     vm_address_t code;
 100     _krncall(vm_allocate(task, &code, trampoline->size_, true));
 101     vm_write(task, code, reinterpret_cast<vm_address_t>(trampoline->data_), trampoline->size_);
 102     _krncall(vm_protect(task, code, trampoline->size_, false, VM_PROT_READ | VM_PROT_EXECUTE));
 103
 104     /*
 105     printf("_ptss:%p\n", baton->__pthread_set_self);
 106     printf("dlsym:%p\n", baton->dlsym);
 107     printf("code:%zx\n", (size_t) code);
 108     */
 109
 110     uint32_t frame[push];
 111     if (sizeof(frame) != 0)
 112         memset(frame, 0, sizeof(frame));
 113     memset(&state, 0, sizeof(state));
 114
 115     mach_msg_type_number_t read(count);
 116     _krncall(thread_get_state(thread, flavor, reinterpret_cast<thread_state_t>(&state), &read));
 117     _assert(count == count);
 118
 119 #if defined(__arm__)
 120     state.r[0] = data;
 121     state.sp = stack + Stack_;
 122     state.pc = code + trampoline->entry_;
 123
 124     if ((state.pc & 0x1) != 0) {
 125         state.pc &= ~0x1;
 126         state.cpsr |= 0x20;
 127     }
 128 #elif defined(__i386__)
 129     frame[1] = data;
 130
 131     state.__eip = code + trampoline->entry_;
 132     state.__esp = stack + Stack_ - sizeof(frame);
 133 #elif defined(__x86_64__)
 134     frame[0] = 0xdeadbeef;
 135     state.__rdi = data;
 136     state.__rip = code + trampoline->entry_;
 137     state.__rsp = stack + Stack_ - sizeof(frame);
 138 #else
 139     #error XXX: implement
 140 #endif
 141
 142     if (sizeof(frame) != 0)
 143         vm_write(task, stack + Stack_ - sizeof(frame), reinterpret_cast<vm_address_t>(frame), sizeof(frame));
 144
 145     _krncall(thread_set_state(thread, flavor, reinterpret_cast<thread_state_t>(&state), count));
 146     _krncall(thread_resume(thread));
 147
 148     _krncall(mach_port_deallocate(self, task));
 149 }