1 /*- 2 * Copyright (c) 2006,2008-2011 Joseph Koshy 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $Id: _libelf.h,v 1.3 2020/05/18 06:46:23 jsg Exp $ 27 */ 28 29 #ifndef __LIBELF_H_ 30 #define __LIBELF_H_ 31 32 #include <sys/queue.h> 33 34 #include "_libelf_config.h" 35 36 #include "_elftc.h" 37 38 /* 39 * Library-private data structures. 40 */ 41 42 #define LIBELF_MSG_SIZE 256 43 44 struct _libelf_globals { 45 int libelf_arch; 46 unsigned int libelf_byteorder; 47 int libelf_class; 48 int libelf_error; 49 int libelf_fillchar; 50 unsigned int libelf_version; 51 unsigned char libelf_msg[LIBELF_MSG_SIZE]; 52 }; 53 54 extern struct _libelf_globals _libelf; 55 56 #define LIBELF_PRIVATE(N) (_libelf.libelf_##N) 57 58 #define LIBELF_ELF_ERROR_MASK 0xFF 59 #define LIBELF_OS_ERROR_SHIFT 8 60 61 #define LIBELF_ERROR(E, O) (((E) & LIBELF_ELF_ERROR_MASK) | \ 62 ((O) << LIBELF_OS_ERROR_SHIFT)) 63 64 #define LIBELF_SET_ERROR(E, O) do { \ 65 LIBELF_PRIVATE(error) = LIBELF_ERROR(ELF_E_##E, (O)); \ 66 } while (0) 67 68 #define LIBELF_ADJUST_AR_SIZE(S) (((S) + 1U) & ~1U) 69 70 /* 71 * Flags for library internal use. These use the upper 16 bits of the 72 * `e_flags' field. 73 */ 74 #define LIBELF_F_API_MASK 0x00FFFFU /* Flags defined by the API. */ 75 #define LIBELF_F_AR_HEADER 0x010000U /* translated header available */ 76 #define LIBELF_F_AR_VARIANT_SVR4 0x020000U /* BSD style ar(1) archive */ 77 #define LIBELF_F_DATA_MALLOCED 0x040000U /* whether data was malloc'ed */ 78 #define LIBELF_F_RAWFILE_MALLOC 0x080000U /* whether e_rawfile was malloc'ed */ 79 #define LIBELF_F_RAWFILE_MMAP 0x100000U /* whether e_rawfile was mmap'ed */ 80 #define LIBELF_F_SHDRS_LOADED 0x200000U /* whether all shdrs were read in */ 81 #define LIBELF_F_SPECIAL_FILE 0x400000U /* non-regular file */ 82 83 struct _Elf { 84 int e_activations; /* activation count */ 85 unsigned int e_byteorder; /* ELFDATA* */ 86 int e_class; /* ELFCLASS* */ 87 Elf_Cmd e_cmd; /* ELF_C_* used at creation time */ 88 int e_fd; /* associated file descriptor */ 89 unsigned int e_flags; /* ELF_F_* & LIBELF_F_* flags */ 90 Elf_Kind e_kind; /* ELF_K_* */ 91 Elf *e_parent; /* non-NULL for archive members */ 92 unsigned char *e_rawfile; /* uninterpreted bytes */ 93 off_t e_rawsize; /* size of uninterpreted bytes */ 94 unsigned int e_version; /* file version */ 95 96 /* 97 * Header information for archive members. See the 98 * LIBELF_F_AR_HEADER flag. 99 */ 100 union { 101 Elf_Arhdr *e_arhdr; /* translated header */ 102 unsigned char *e_rawhdr; /* untranslated header */ 103 } e_hdr; 104 105 union { 106 struct { /* ar(1) archives */ 107 off_t e_next; /* set by elf_rand()/elf_next() */ 108 int e_nchildren; 109 unsigned char *e_rawstrtab; /* file name strings */ 110 size_t e_rawstrtabsz; 111 unsigned char *e_rawsymtab; /* symbol table */ 112 size_t e_rawsymtabsz; 113 Elf_Arsym *e_symtab; 114 size_t e_symtabsz; 115 } e_ar; 116 struct { /* regular ELF files */ 117 union { 118 Elf32_Ehdr *e_ehdr32; 119 Elf64_Ehdr *e_ehdr64; 120 } e_ehdr; 121 union { 122 Elf32_Phdr *e_phdr32; 123 Elf64_Phdr *e_phdr64; 124 } e_phdr; 125 STAILQ_HEAD(, _Elf_Scn) e_scn; /* section list */ 126 size_t e_nphdr; /* number of Phdr entries */ 127 size_t e_nscn; /* number of sections */ 128 size_t e_strndx; /* string table section index */ 129 } e_elf; 130 } e_u; 131 }; 132 133 /* 134 * The internal descriptor wrapping the "Elf_Data" type. 135 */ 136 struct _Libelf_Data { 137 Elf_Data d_data; /* The exported descriptor. */ 138 Elf_Scn *d_scn; /* The containing section */ 139 unsigned int d_flags; 140 STAILQ_ENTRY(_Libelf_Data) d_next; 141 }; 142 143 struct _Elf_Scn { 144 union { 145 Elf32_Shdr s_shdr32; 146 Elf64_Shdr s_shdr64; 147 } s_shdr; 148 STAILQ_HEAD(, _Libelf_Data) s_data; /* translated data */ 149 STAILQ_HEAD(, _Libelf_Data) s_rawdata; /* raw data */ 150 STAILQ_ENTRY(_Elf_Scn) s_next; 151 struct _Elf *s_elf; /* parent ELF descriptor */ 152 unsigned int s_flags; /* flags for the section as a whole */ 153 size_t s_ndx; /* index# for this section */ 154 uint64_t s_offset; /* managed by elf_update() */ 155 uint64_t s_rawoff; /* original offset in the file */ 156 uint64_t s_size; /* managed by elf_update() */ 157 }; 158 159 160 enum { 161 ELF_TOFILE, 162 ELF_TOMEMORY 163 }; 164 165 166 /* 167 * The LIBELF_COPY macros are used to copy fields from a GElf_* 168 * structure to their 32-bit counterparts, while checking for out of 169 * range values. 170 * 171 * - LIBELF_COPY_U32 :: copy an unsigned 32 bit field. 172 * - LIBELF_COPY_S32 :: copy a signed 32 bit field. 173 */ 174 175 #define LIBELF_COPY_U32(DST, SRC, NAME) do { \ 176 if ((SRC)->NAME > UINT32_MAX) { \ 177 LIBELF_SET_ERROR(RANGE, 0); \ 178 return (0); \ 179 } \ 180 (DST)->NAME = (SRC)->NAME & 0xFFFFFFFFU; \ 181 } while (0) 182 183 #define LIBELF_COPY_S32(DST, SRC, NAME) do { \ 184 if ((SRC)->NAME > INT32_MAX || \ 185 (SRC)->NAME < INT32_MIN) { \ 186 LIBELF_SET_ERROR(RANGE, 0); \ 187 return (0); \ 188 } \ 189 (DST)->NAME = (int32_t) (SRC)->NAME; \ 190 } while (0) 191 192 193 /* 194 * Function Prototypes. 195 */ 196 197 typedef int _libelf_translator_function(unsigned char *_dst, size_t dsz, 198 unsigned char *_src, size_t _cnt, int _byteswap); 199 200 #ifdef __cplusplus 201 extern "C" { 202 #endif 203 struct _Libelf_Data *_libelf_allocate_data(Elf_Scn *_s); 204 Elf *_libelf_allocate_elf(void); 205 Elf_Scn *_libelf_allocate_scn(Elf *_e, size_t _ndx); 206 Elf_Arhdr *_libelf_ar_gethdr(Elf *_e); 207 Elf *_libelf_ar_open(Elf *_e, int _reporterror); 208 Elf *_libelf_ar_open_member(int _fd, Elf_Cmd _c, Elf *_ar); 209 Elf_Arsym *_libelf_ar_process_bsd_symtab(Elf *_ar, size_t *_dst); 210 Elf_Arsym *_libelf_ar_process_svr4_symtab(Elf *_ar, size_t *_dst); 211 long _libelf_checksum(Elf *_e, int _elfclass); 212 void *_libelf_ehdr(Elf *_e, int _elfclass, int _allocate); 213 int _libelf_elfmachine(Elf *_e); 214 unsigned int _libelf_falign(Elf_Type _t, int _elfclass); 215 size_t _libelf_fsize(Elf_Type _t, int _elfclass, unsigned int _version, 216 size_t count); 217 _libelf_translator_function *_libelf_get_translator(Elf_Type _t, 218 int _direction, int _elfclass, int _elfmachine); 219 void *_libelf_getphdr(Elf *_e, int _elfclass); 220 void *_libelf_getshdr(Elf_Scn *_scn, int _elfclass); 221 void _libelf_init_elf(Elf *_e, Elf_Kind _kind); 222 int _libelf_load_section_headers(Elf *e, void *ehdr); 223 unsigned int _libelf_malign(Elf_Type _t, int _elfclass); 224 Elf *_libelf_memory(unsigned char *_image, size_t _sz, int _reporterror); 225 size_t _libelf_msize(Elf_Type _t, int _elfclass, unsigned int _version); 226 void *_libelf_newphdr(Elf *_e, int _elfclass, size_t _count); 227 Elf *_libelf_open_object(int _fd, Elf_Cmd _c, int _reporterror); 228 struct _Libelf_Data *_libelf_release_data(struct _Libelf_Data *_d); 229 void _libelf_release_elf(Elf *_e); 230 Elf_Scn *_libelf_release_scn(Elf_Scn *_s); 231 int _libelf_setphnum(Elf *_e, void *_eh, int _elfclass, size_t _phnum); 232 int _libelf_setshnum(Elf *_e, void *_eh, int _elfclass, size_t _shnum); 233 int _libelf_setshstrndx(Elf *_e, void *_eh, int _elfclass, 234 size_t _shstrndx); 235 Elf_Data *_libelf_xlate(Elf_Data *_d, const Elf_Data *_s, 236 unsigned int _encoding, int _elfclass, int _elfmachine, int _direction); 237 int _libelf_xlate_shtype(uint32_t _sht); 238 #ifdef __cplusplus 239 } 240 #endif 241 242 #endif /* __LIBELF_H_ */ 243