dl_iterate_phdr_static.c revision 405b8029a6888f386adf3512113a33546141d1c8
1405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham/* 2405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * Copyright (C) 2006 The Android Open Source Project 3405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * All rights reserved. 4405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 5405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * Redistribution and use in source and binary forms, with or without 6405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * modification, are permitted provided that the following conditions 7405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * are met: 8405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * * Redistributions of source code must retain the above copyright 9405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * notice, this list of conditions and the following disclaimer. 10405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * * Redistributions in binary form must reproduce the above copyright 11405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * notice, this list of conditions and the following disclaimer in 12405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * the documentation and/or other materials provided with the 13405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * distribution. 14405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 15405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * SUCH DAMAGE. 27405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham */ 28405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 29405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#include <sys/types.h> 30405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#include <linux/elf.h> 31405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 32405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham/* TODO: Move this into a header that linker.h can also pull it in. 33405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * Silly to have same struct in 2 places. This is temporary. */ 34405b8029a6888f386adf3512113a33546141d1c8Raghu Gandhamstruct dl_phdr_info 35405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham{ 36405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham Elf32_Addr dlpi_addr; 37405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham const char *dlpi_name; 38405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham const Elf32_Phdr *dlpi_phdr; 39405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham Elf32_Half dlpi_phnum; 40405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham}; 41405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 42405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham/* Dynamic binaries get this from the dynamic linker (system/linker), which 43405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * we don't pull in for static bins. We also don't have a list of so's to 44405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * iterate over, since there's really only a single monolithic blob of 45405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * code/data. 46405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 47405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * All we need to do is to find where the executable is in memory, and grab the 48405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * phdr and phnum from there. 49405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham */ 50405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 51405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham/* ld provides this to us in the default link script */ 52405b8029a6888f386adf3512113a33546141d1c8Raghu Gandhamextern void *__executable_start; 53405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 54405b8029a6888f386adf3512113a33546141d1c8Raghu Gandhamint 55405b8029a6888f386adf3512113a33546141d1c8Raghu Gandhamdl_iterate_phdr(int (*cb)(struct dl_phdr_info *info, size_t size, void *data), 56405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham void *data) 57405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham{ 58405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham struct dl_phdr_info dl_info; 59405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham Elf32_Ehdr *ehdr = (Elf32_Ehdr *) &__executable_start; 60405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham Elf32_Phdr *phdr = (Elf32_Phdr *)((unsigned long)ehdr + ehdr->e_phoff); 61405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 62405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham /* TODO: again, copied from linker.c. Find a better home for this 63405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * later. */ 64405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham if (ehdr->e_ident[EI_MAG0] != ELFMAG0) return -1; 65405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham if (ehdr->e_ident[EI_MAG1] != ELFMAG1) return -1; 66405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham if (ehdr->e_ident[EI_MAG2] != ELFMAG2) return -1; 67405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham if (ehdr->e_ident[EI_MAG3] != ELFMAG3) return -1; 68405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 69405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham dl_info.dlpi_addr = 0; 70405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham dl_info.dlpi_name = NULL; 71405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham dl_info.dlpi_phdr = phdr; 72405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham dl_info.dlpi_phnum = ehdr->e_phnum; 73405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham return cb(&dl_info, sizeof (struct dl_phdr_info), data); 74405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham} 75