paul@327 | 1 | /* |
paul@327 | 2 | * ELF payload decoding support. |
paul@327 | 3 | * |
paul@327 | 4 | * Copyright (C) 2022 Paul Boddie <paul@boddie.org.uk> |
paul@327 | 5 | * |
paul@327 | 6 | * This program is free software; you can redistribute it and/or |
paul@327 | 7 | * modify it under the terms of the GNU General Public License as |
paul@327 | 8 | * published by the Free Software Foundation; either version 2 of |
paul@327 | 9 | * the License, or (at your option) any later version. |
paul@327 | 10 | * |
paul@327 | 11 | * This program is distributed in the hope that it will be useful, |
paul@327 | 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
paul@327 | 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
paul@327 | 14 | * GNU General Public License for more details. |
paul@327 | 15 | * |
paul@327 | 16 | * You should have received a copy of the GNU General Public License |
paul@327 | 17 | * along with this program; if not, write to the Free Software |
paul@327 | 18 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, |
paul@327 | 19 | * Boston, MA 02110-1301, USA |
paul@327 | 20 | */ |
paul@327 | 21 | |
paul@327 | 22 | #include <l4/util/elf.h> |
paul@327 | 23 | |
paul@327 | 24 | #include "elf.h" |
paul@327 | 25 | |
paul@327 | 26 | |
paul@327 | 27 | |
paul@327 | 28 | /* Program segment construction for 32- or 64-bit variants. */ |
paul@327 | 29 | |
paul@327 | 30 | template <typename PROGRAM_HEADER> |
paul@327 | 31 | ProgramSegmentVariant<PROGRAM_HEADER>::ProgramSegmentVariant(PROGRAM_HEADER *header) |
paul@327 | 32 | : _header(header) |
paul@327 | 33 | { |
paul@349 | 34 | init(); |
paul@327 | 35 | } |
paul@327 | 36 | |
paul@327 | 37 | template <typename PROGRAM_HEADER> |
paul@327 | 38 | bool ProgramSegmentVariant<PROGRAM_HEADER>::loadable() |
paul@327 | 39 | { |
paul@327 | 40 | return _header->p_type == PT_LOAD; |
paul@327 | 41 | } |
paul@327 | 42 | |
paul@327 | 43 | template <typename PROGRAM_HEADER> |
paul@327 | 44 | offset_t ProgramSegmentVariant<PROGRAM_HEADER>::file_contents() |
paul@327 | 45 | { |
paul@327 | 46 | return _header->p_filesz; |
paul@327 | 47 | } |
paul@327 | 48 | |
paul@327 | 49 | template <typename PROGRAM_HEADER> |
paul@327 | 50 | offset_t ProgramSegmentVariant<PROGRAM_HEADER>::file_offset() |
paul@327 | 51 | { |
paul@327 | 52 | return _header->p_offset; |
paul@327 | 53 | } |
paul@327 | 54 | |
paul@327 | 55 | template <typename PROGRAM_HEADER> |
paul@327 | 56 | l4_addr_t ProgramSegmentVariant<PROGRAM_HEADER>::region_address() |
paul@327 | 57 | { |
paul@327 | 58 | return _header->p_vaddr; |
paul@327 | 59 | } |
paul@327 | 60 | |
paul@327 | 61 | template <typename PROGRAM_HEADER> |
paul@327 | 62 | offset_t ProgramSegmentVariant<PROGRAM_HEADER>::region_size() |
paul@327 | 63 | { |
paul@327 | 64 | return _header->p_memsz; |
paul@327 | 65 | } |
paul@327 | 66 | |
paul@327 | 67 | template <typename PROGRAM_HEADER> |
paul@327 | 68 | l4re_rm_flags_t ProgramSegmentVariant<PROGRAM_HEADER>::region_flags() |
paul@327 | 69 | { |
paul@327 | 70 | l4re_rm_flags_t flags = 0; |
paul@327 | 71 | |
paul@327 | 72 | if (_header->p_flags & PF_R) |
paul@327 | 73 | flags |= L4RE_RM_F_R; |
paul@327 | 74 | if (_header->p_flags & PF_W) |
paul@327 | 75 | flags |= L4RE_RM_F_W; |
paul@327 | 76 | if (_header->p_flags & PF_X) |
paul@327 | 77 | flags |= L4RE_RM_F_X; |
paul@327 | 78 | |
paul@327 | 79 | return flags; |
paul@327 | 80 | } |
paul@327 | 81 | |
paul@327 | 82 | |
paul@327 | 83 | |
paul@349 | 84 | /* Generic payload destruction. */ |
paul@349 | 85 | |
paul@349 | 86 | Payload::~Payload() |
paul@349 | 87 | { |
paul@349 | 88 | if (_segments != NULL) |
paul@349 | 89 | { |
paul@349 | 90 | for (unsigned int i = 0; i < segments(); i++) |
paul@349 | 91 | delete _segments[i]; |
paul@349 | 92 | } |
paul@349 | 93 | } |
paul@349 | 94 | |
paul@349 | 95 | unsigned int Payload::segments() |
paul@349 | 96 | { |
paul@349 | 97 | return 0; |
paul@349 | 98 | } |
paul@349 | 99 | |
paul@349 | 100 | |
paul@349 | 101 | |
paul@327 | 102 | /* ELF payload construction for 32- or 64-bit variants. */ |
paul@327 | 103 | |
paul@327 | 104 | template <typename HEADER, typename PROGRAM_HEADER> |
paul@327 | 105 | PayloadVariant<HEADER, PROGRAM_HEADER>::PayloadVariant(HEADER *header) |
paul@327 | 106 | : _header(header) |
paul@327 | 107 | { |
paul@327 | 108 | } |
paul@327 | 109 | |
paul@327 | 110 | template <typename HEADER, typename PROGRAM_HEADER> |
paul@327 | 111 | l4_addr_t PayloadVariant<HEADER, PROGRAM_HEADER>::entry_point() |
paul@327 | 112 | { |
paul@327 | 113 | return _header->e_entry; |
paul@327 | 114 | } |
paul@327 | 115 | |
paul@327 | 116 | template <typename HEADER, typename PROGRAM_HEADER> |
paul@327 | 117 | offset_t PayloadVariant<HEADER, PROGRAM_HEADER>::header_extent() |
paul@327 | 118 | { |
paul@327 | 119 | return sizeof(HEADER); |
paul@327 | 120 | } |
paul@327 | 121 | |
paul@327 | 122 | template <typename HEADER, typename PROGRAM_HEADER> |
paul@327 | 123 | offset_t PayloadVariant<HEADER, PROGRAM_HEADER>::program_header_extent() |
paul@327 | 124 | { |
paul@327 | 125 | return _header->e_phoff + _header->e_phentsize * _header->e_phnum; |
paul@327 | 126 | } |
paul@327 | 127 | |
paul@327 | 128 | template <typename HEADER, typename PROGRAM_HEADER> |
paul@327 | 129 | unsigned int PayloadVariant<HEADER, PROGRAM_HEADER>::segments() |
paul@327 | 130 | { |
paul@327 | 131 | return _header->e_phnum; |
paul@327 | 132 | } |
paul@327 | 133 | |
paul@327 | 134 | template <typename HEADER, typename PROGRAM_HEADER> |
paul@349 | 135 | Segment *PayloadVariant<HEADER, PROGRAM_HEADER>::segment(unsigned int i) |
paul@327 | 136 | { |
paul@327 | 137 | if (i >= segments()) |
paul@327 | 138 | return NULL; |
paul@327 | 139 | |
paul@349 | 140 | if (_segments == NULL) |
paul@349 | 141 | { |
paul@349 | 142 | _segments = new Segment *[segments()]; |
paul@349 | 143 | |
paul@349 | 144 | for (unsigned int j = 0; j < segments(); j++) |
paul@349 | 145 | _segments[j] = NULL; |
paul@349 | 146 | } |
paul@349 | 147 | |
paul@349 | 148 | Segment *segment = _segments[i]; |
paul@349 | 149 | |
paul@349 | 150 | if (segment == NULL) |
paul@349 | 151 | { |
paul@349 | 152 | segment = new ProgramSegmentVariant<PROGRAM_HEADER>( |
paul@349 | 153 | (PROGRAM_HEADER *) ((char *) _header + _header->e_phoff + |
paul@349 | 154 | _header->e_phentsize * i)); |
paul@349 | 155 | _segments[i] = segment; |
paul@349 | 156 | } |
paul@349 | 157 | |
paul@349 | 158 | return segment; |
paul@327 | 159 | } |
paul@327 | 160 | |
paul@327 | 161 | |
paul@327 | 162 | |
paul@327 | 163 | /* Return the appropriate payload object. */ |
paul@327 | 164 | |
paul@356 | 165 | Payload *exec_open_payload(char *buf) |
paul@327 | 166 | { |
paul@327 | 167 | switch (buf[EI_CLASS]) |
paul@327 | 168 | { |
paul@327 | 169 | case (char) 1: |
paul@327 | 170 | return new PayloadVariant<Elf32_Ehdr, Elf32_Phdr>((Elf32_Ehdr *) buf); |
paul@327 | 171 | case (char) 2: |
paul@327 | 172 | return new PayloadVariant<Elf64_Ehdr, Elf64_Phdr>((Elf64_Ehdr *) buf); |
paul@327 | 173 | default: |
paul@327 | 174 | return NULL; |
paul@327 | 175 | } |
paul@327 | 176 | } |
paul@327 | 177 | |
paul@327 | 178 | /* vim: tabstop=2 expandtab shiftwidth=2 |
paul@327 | 179 | */ |