15821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* 25821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * Copyright (c) 2012 The Chromium Authors. All rights reserved. 35821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * Use of this source code is governed by a BSD-style license that can be 45821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * found in the LICENSE file. 55821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) */ 65821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 75821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "native_client/src/include/elf32.h" 85821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "native_client/src/include/elf_auxv.h" 95821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "native_client/src/include/nacl_macros.h" 105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "native_client/src/untrusted/nacl/nacl_startup.h" 119ab5563a3196760eb381d102cbb2bc0f7abc6a50Ben Murdoch#include "ppapi/native_client/src/untrusted/pnacl_irt_shim/shim_ppapi.h" 125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 135821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 145821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* 155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * This is the true entry point for untrusted code. 165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * See nacl_startup.h for the layout at the argument pointer. 175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) */ 185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)void _pnacl_wrapper_start(uint32_t *info) { 195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) Elf32_auxv_t *auxv = nacl_startup_auxv(info); 205821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) Elf32_auxv_t *entry = NULL; 225821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) for (Elf32_auxv_t *av = auxv; av->a_type != AT_NULL; ++av) { 235821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (av->a_type == AT_SYSINFO) { 245821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) entry = av; 255821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) break; 265821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 275821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 285821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 295821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (entry != NULL) { 305821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) /* 31a1401311d1ab56c4ed0a474bd38c108f75cb0cd9Torne (Richard Coles) * Save the real irt interface query function. 325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) */ 33a1401311d1ab56c4ed0a474bd38c108f75cb0cd9Torne (Richard Coles) __pnacl_real_irt_query_func = (TYPE_nacl_irt_query) entry->a_un.a_val; 345821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 355821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) /* 365821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * Overwrite the auxv slot with the pnacl IRT shim query function. 375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) */ 385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) entry->a_type = AT_SYSINFO; 39a1401311d1ab56c4ed0a474bd38c108f75cb0cd9Torne (Richard Coles) entry->a_un.a_val = (uintptr_t) __pnacl_wrap_irt_query_func; 405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) /* If entry is NULL still allow startup to continue. It may be the case 435821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * that the IRT was not actually used (e.g., for some commandline tests). 445821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * For newlib, we can tell that the IRT isn't used when libnacl_sys_private.a 455821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * is in the bitcode link line. However, glibc does not use 465821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * libnacl_sys_private, so that would not work. We could look for -lppapi 475821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * in the bitcode link line, but looking at the bitcode link line 485821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * seems brittle (what if the bitcode link was separated from translation). 495821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * Thus we always wrap _start, even if there is no IRT auxv entry. 505821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) */ 515821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 525821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) /* 535821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * Call the user entry point function. It should not return. 545821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * TODO(sehr): Find a way to ensure this is invoked via a tail call. 555821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) */ 565821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) _start(info); 575821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 58