1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586878889909192939495969798991001011021031041051061071081091101111121131141151161171181191201211221231241251261271281291301311321331341351361371381391401411421431441451461471481491501511521531541551561571581591601611621631641651661671681691701711721731741751761771781791801811821831841851861871881891901911921931941951961971981992002012022032042052062072082092102112122132142152162172182192202212222232242252262272282292302312322332342352362372382392402412422432442452462472482492502512522532542552562572582592602612622632642652662672682692702712722732742752762772782792802812822832842852862872882892902912922932942952962972982993003013023033043053063073083093103113123133143153163173183193203213223233243253263273283293303313323333343353363373383393403413423433443453463473483493503513523533543553563573583593603613623633643653663673683693703713723733743753763773783793803813823833843853863873883893903913923933943953963973983994004014024034044054064074084094104114124134144154164174184194204214224234244254264274284294304314324334344354364374384394404414424434444454464474484494504514524534544554564574584594604614624634644654664674684694704714724734744754764774784794804814824834844854864874884894904914924934944954964974984995005015025035045055065075085095105115125135145155165175185195205215225235245255265275285295305315325335345355365375385395405415425435445455465475485495505515525535545555565575585595605615625635645655665675685695705715725735745755765775785795805815825835845855865875885895905915925935945955965975985996006016026036046056066076086096106116126136146156166176186196206216226236246256266276286296306316326336346356366376386396406416426436446456466476486496506516526536546556566576586596606616626636646656666676686696706716726736746756766776786796806816826836846856866876886896906916926936946956966976986997007017027037047057067077087097107117127137147157167177187197207217227237247257267277287297307317327337347357367377387397407417427437447457467477487497507517527537547557567577587597607617627637647657667677687697707717727737747757767777787797807817827837847857867877887897907917927937947957967977987998008018028038048058068078088098108118128138148158168178188198208218228238248258268278288298308318328338348358368378388398408418428438448458468478488498508518528538548558568578588598608618628638648658668678688698708718728738748758768778788798808818828838848858868878888898908918928938948958968978988999009019029039049059069079089099109119129139149159169179189199209219229239249259269279289299309319329339349359369379389399409419429439449459469479489499509519529539549559569579589599609619629639649659669679689699709719729739749759769779789799809819829839849859869879889899909919929939949959969979989991000100110021003100410051006100710081009101010111012101310141015101610171018101910201021102210231024102510261027102810291030103110321033103410351036103710381039104010411042104310441045104610471048104910501051105210531054105510561057105810591060106110621063106410651066106710681069107010711072107310741075107610771078107910801081108210831084108510861087108810891090109110921093109410951096109710981099110011011102110311041105110611071108110911101111111211131114111511161117111811191120112111221123112411251126112711281129113011311132113311341135113611371138113911401141114211431144114511461147114811491150115111521153115411551156115711581159116011611162116311641165116611671168116911701171117211731174117511761177117811791180118111821183118411851186118711881189119011911192119311941195119611971198119912001201120212031204120512061207120812091210121112121213121412151216121712181219122012211222122312241225122612271228122912301231123212331234123512361237123812391240124112421243124412451246124712481249125012511252125312541255125612571258125912601261126212631264126512661267126812691270127112721273127412751276127712781279128012811282128312841285128612871288128912901291129212931294129512961297129812991300130113021303130413051306130713081309131013111312131313141315131613171318131913201321132213231324132513261327132813291330133113321333133413351336133713381339134013411342134313441345134613471348134913501351135213531354135513561357135813591360136113621363136413651366136713681369137013711372137313741375137613771378137913801381138213831384138513861387138813891390139113921393139413951396139713981399140014011402140314041405140614071408140914101411141214131414141514161417141814191420142114221423142414251426142714281429143014311432143314341435143614371438143914401441144214431444144514461447144814491450145114521453145414551456145714581459146014611462146314641465146614671468146914701471147214731474147514761477147814791480148114821483148414851486148714881489149014911492149314941495149614971498149915001501150215031504150515061507150815091510151115121513151415151516151715181519152015211522152315241525152615271528152915301531153215331534153515361537153815391540154115421543154415451546154715481549155015511552155315541555155615571558155915601561156215631564156515661567156815691570157115721573157415751576157715781579158015811582158315841585158615871588158915901591159215931594159515961597159815991600160116021603160416051606160716081609161016111612 |
- /* simple-object-elf.c -- routines to manipulate ELF object files.
- Copyright (C) 2010-2022 Free Software Foundation, Inc.
- Written by Ian Lance Taylor, Google.
- This program is free software; you can redistribute it and/or modify it
- under the terms of the GNU General Public License as published by the
- Free Software Foundation; either version 2, or (at your option) any
- later version.
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, 51 Franklin Street - Fifth Floor,
- Boston, MA 02110-1301, USA. */
- #include "config.h"
- #include "libiberty.h"
- #include "simple-object.h"
- #include <errno.h>
- /* mingw.org's MinGW doesn't have ENOTSUP. */
- #ifndef ENOTSUP
- # define ENOTSUP ENOSYS
- #endif
- #include <stddef.h>
- #ifdef HAVE_STDLIB_H
- #include <stdlib.h>
- #endif
- #ifdef HAVE_STDINT_H
- #include <stdint.h>
- #endif
- #ifdef HAVE_STRING_H
- #include <string.h>
- #endif
- #ifdef HAVE_INTTYPES_H
- #include <inttypes.h>
- #endif
- #include "simple-object-common.h"
- /* ELF structures and constants. */
- /* 32-bit ELF file header. */
- typedef struct {
- unsigned char e_ident[16]; /* ELF "magic number" */
- unsigned char e_type[2]; /* Identifies object file type */
- unsigned char e_machine[2]; /* Specifies required architecture */
- unsigned char e_version[4]; /* Identifies object file version */
- unsigned char e_entry[4]; /* Entry point virtual address */
- unsigned char e_phoff[4]; /* Program header table file offset */
- unsigned char e_shoff[4]; /* Section header table file offset */
- unsigned char e_flags[4]; /* Processor-specific flags */
- unsigned char e_ehsize[2]; /* ELF header size in bytes */
- unsigned char e_phentsize[2]; /* Program header table entry size */
- unsigned char e_phnum[2]; /* Program header table entry count */
- unsigned char e_shentsize[2]; /* Section header table entry size */
- unsigned char e_shnum[2]; /* Section header table entry count */
- unsigned char e_shstrndx[2]; /* Section header string table index */
- } Elf32_External_Ehdr;
- /* 64-bit ELF file header. */
- typedef struct {
- unsigned char e_ident[16]; /* ELF "magic number" */
- unsigned char e_type[2]; /* Identifies object file type */
- unsigned char e_machine[2]; /* Specifies required architecture */
- unsigned char e_version[4]; /* Identifies object file version */
- unsigned char e_entry[8]; /* Entry point virtual address */
- unsigned char e_phoff[8]; /* Program header table file offset */
- unsigned char e_shoff[8]; /* Section header table file offset */
- unsigned char e_flags[4]; /* Processor-specific flags */
- unsigned char e_ehsize[2]; /* ELF header size in bytes */
- unsigned char e_phentsize[2]; /* Program header table entry size */
- unsigned char e_phnum[2]; /* Program header table entry count */
- unsigned char e_shentsize[2]; /* Section header table entry size */
- unsigned char e_shnum[2]; /* Section header table entry count */
- unsigned char e_shstrndx[2]; /* Section header string table index */
- } Elf64_External_Ehdr;
- /* Indexes and values in e_ident field of Ehdr. */
- #define EI_MAG0 0 /* File identification byte 0 index */
- #define ELFMAG0 0x7F /* Magic number byte 0 */
- #define EI_MAG1 1 /* File identification byte 1 index */
- #define ELFMAG1 'E' /* Magic number byte 1 */
- #define EI_MAG2 2 /* File identification byte 2 index */
- #define ELFMAG2 'L' /* Magic number byte 2 */
- #define EI_MAG3 3 /* File identification byte 3 index */
- #define ELFMAG3 'F' /* Magic number byte 3 */
- #define EI_CLASS 4 /* File class */
- #define ELFCLASSNONE 0 /* Invalid class */
- #define ELFCLASS32 1 /* 32-bit objects */
- #define ELFCLASS64 2 /* 64-bit objects */
- #define EI_DATA 5 /* Data encoding */
- #define ELFDATANONE 0 /* Invalid data encoding */
- #define ELFDATA2LSB 1 /* 2's complement, little endian */
- #define ELFDATA2MSB 2 /* 2's complement, big endian */
- #define EI_VERSION 6 /* File version */
- #define EV_CURRENT 1 /* Current version */
- #define EI_OSABI 7 /* Operating System/ABI indication */
- /* Values for e_type field of Ehdr. */
- #define ET_REL 1 /* Relocatable file */
- /* Values for e_machine field of Ehdr. */
- #define EM_SPARC 2 /* SUN SPARC */
- #define EM_SPARC32PLUS 18 /* Sun's "v8plus" */
- /* Special section index values. */
- #define SHN_UNDEF 0 /* Undefined section */
- #define SHN_LORESERVE 0xFF00 /* Begin range of reserved indices */
- #define SHN_COMMON 0xFFF2 /* Associated symbol is in common */
- #define SHN_XINDEX 0xFFFF /* Section index is held elsewhere */
- #define SHN_HIRESERVE 0xffff /* End of reserved indices */
- /* 32-bit ELF program header. */
- typedef struct {
- unsigned char p_type[4]; /* Identifies program segment type */
- unsigned char p_offset[4]; /* Segment file offset */
- unsigned char p_vaddr[4]; /* Segment virtual address */
- unsigned char p_paddr[4]; /* Segment physical address */
- unsigned char p_filesz[4]; /* Segment size in file */
- unsigned char p_memsz[4]; /* Segment size in memory */
- unsigned char p_flags[4]; /* Segment flags */
- unsigned char p_align[4]; /* Segment alignment, file & memory */
- } Elf32_External_Phdr;
- /* 64-bit ELF program header. */
- typedef struct {
- unsigned char p_type[4]; /* Identifies program segment type */
- unsigned char p_flags[4]; /* Segment flags */
- unsigned char p_offset[8]; /* Segment file offset */
- unsigned char p_vaddr[8]; /* Segment virtual address */
- unsigned char p_paddr[8]; /* Segment physical address */
- unsigned char p_filesz[8]; /* Segment size in file */
- unsigned char p_memsz[8]; /* Segment size in memory */
- unsigned char p_align[8]; /* Segment alignment, file & memory */
- } Elf64_External_Phdr;
- /* 32-bit ELF section header */
- typedef struct {
- unsigned char sh_name[4]; /* Section name, index in string tbl */
- unsigned char sh_type[4]; /* Type of section */
- unsigned char sh_flags[4]; /* Miscellaneous section attributes */
- unsigned char sh_addr[4]; /* Section virtual addr at execution */
- unsigned char sh_offset[4]; /* Section file offset */
- unsigned char sh_size[4]; /* Size of section in bytes */
- unsigned char sh_link[4]; /* Index of another section */
- unsigned char sh_info[4]; /* Additional section information */
- unsigned char sh_addralign[4]; /* Section alignment */
- unsigned char sh_entsize[4]; /* Entry size if section holds table */
- } Elf32_External_Shdr;
- /* 64-bit ELF section header. */
- typedef struct {
- unsigned char sh_name[4]; /* Section name, index in string tbl */
- unsigned char sh_type[4]; /* Type of section */
- unsigned char sh_flags[8]; /* Miscellaneous section attributes */
- unsigned char sh_addr[8]; /* Section virtual addr at execution */
- unsigned char sh_offset[8]; /* Section file offset */
- unsigned char sh_size[8]; /* Size of section in bytes */
- unsigned char sh_link[4]; /* Index of another section */
- unsigned char sh_info[4]; /* Additional section information */
- unsigned char sh_addralign[8]; /* Section alignment */
- unsigned char sh_entsize[8]; /* Entry size if section holds table */
- } Elf64_External_Shdr;
- /* Values for sh_type field. */
- #define SHT_NULL 0 /* Section header table entry unused */
- #define SHT_PROGBITS 1 /* Program data */
- #define SHT_SYMTAB 2 /* Link editing symbol table */
- #define SHT_STRTAB 3 /* A string table */
- #define SHT_RELA 4 /* Relocation entries with addends */
- #define SHT_REL 9 /* Relocation entries, no addends */
- #define SHT_GROUP 17 /* Section contains a section group */
- #define SHT_SYMTAB_SHNDX 18 /* Extended section indeces */
- /* Values for sh_flags field. */
- #define SHF_INFO_LINK 0x00000040 /* `sh_info' contains SHT index */
- #define SHF_EXECINSTR 0x00000004 /* Executable section. */
- #define SHF_EXCLUDE 0x80000000 /* Link editor is to exclude this
- section from executable and
- shared library that it builds
- when those objects are not to be
- further relocated. */
- /* Symbol table entry. */
- typedef struct
- {
- unsigned char st_name[4]; /* Symbol name (string tbl index) */
- unsigned char st_value[4]; /* Symbol value */
- unsigned char st_size[4]; /* Symbol size */
- unsigned char st_info; /* Symbol type and binding */
- unsigned char st_other; /* Symbol visibility */
- unsigned char st_shndx[2]; /* Section index */
- } Elf32_External_Sym;
- typedef struct
- {
- unsigned char st_name[4]; /* Symbol name (string tbl index) */
- unsigned char st_info; /* Symbol type and binding */
- unsigned char st_other; /* Symbol visibility */
- unsigned char st_shndx[2]; /* Section index */
- unsigned char st_value[8]; /* Symbol value */
- unsigned char st_size[8]; /* Symbol size */
- } Elf64_External_Sym;
- #define ELF_ST_BIND(val) (((unsigned char) (val)) >> 4)
- #define ELF_ST_TYPE(val) ((val) & 0xf)
- #define ELF_ST_INFO(bind, type) (((bind) << 4) + ((type) & 0xf))
- #define STT_NOTYPE 0 /* Symbol type is unspecified */
- #define STT_OBJECT 1 /* Symbol is a data object */
- #define STT_FUNC 2 /* Symbol is a code object */
- #define STT_TLS 6 /* Thread local data object */
- #define STT_GNU_IFUNC 10 /* Symbol is an indirect code object */
- #define STB_LOCAL 0 /* Local symbol */
- #define STB_GLOBAL 1 /* Global symbol */
- #define STB_WEAK 2 /* Weak global */
- #define STV_DEFAULT 0 /* Visibility is specified by binding type */
- #define STV_HIDDEN 2 /* Can only be seen inside currect component */
- /* Functions to fetch and store different ELF types, depending on the
- endianness and size. */
- struct elf_type_functions
- {
- unsigned short (*fetch_Elf_Half) (const unsigned char *);
- unsigned int (*fetch_Elf_Word) (const unsigned char *);
- ulong_type (*fetch_Elf_Addr) (const unsigned char *);
- void (*set_Elf_Half) (unsigned char *, unsigned short);
- void (*set_Elf_Word) (unsigned char *, unsigned int);
- void (*set_Elf_Addr) (unsigned char *, ulong_type);
- };
- static const struct elf_type_functions elf_big_32_functions =
- {
- simple_object_fetch_big_16,
- simple_object_fetch_big_32,
- simple_object_fetch_big_32_ulong,
- simple_object_set_big_16,
- simple_object_set_big_32,
- simple_object_set_big_32_ulong
- };
- static const struct elf_type_functions elf_little_32_functions =
- {
- simple_object_fetch_little_16,
- simple_object_fetch_little_32,
- simple_object_fetch_little_32_ulong,
- simple_object_set_little_16,
- simple_object_set_little_32,
- simple_object_set_little_32_ulong
- };
- #ifdef UNSIGNED_64BIT_TYPE
- static const struct elf_type_functions elf_big_64_functions =
- {
- simple_object_fetch_big_16,
- simple_object_fetch_big_32,
- simple_object_fetch_big_64,
- simple_object_set_big_16,
- simple_object_set_big_32,
- simple_object_set_big_64
- };
- static const struct elf_type_functions elf_little_64_functions =
- {
- simple_object_fetch_little_16,
- simple_object_fetch_little_32,
- simple_object_fetch_little_64,
- simple_object_set_little_16,
- simple_object_set_little_32,
- simple_object_set_little_64
- };
- #endif
- /* Hideous macro to fetch the value of a field from an external ELF
- struct of some sort. TYPEFUNCS is the set of type functions.
- BUFFER points to the external data. STRUCTTYPE is the appropriate
- struct type. FIELD is a field within the struct. TYPE is the type
- of the field in the struct: Elf_Half, Elf_Word, or Elf_Addr. */
- #define ELF_FETCH_STRUCT_FIELD(TYPEFUNCS, STRUCTTYPE, FIELD, BUFFER, TYPE) \
- ((TYPEFUNCS)->fetch_ ## TYPE ((BUFFER) + offsetof (STRUCTTYPE, FIELD)))
- /* Even more hideous macro to fetch the value of FIELD from BUFFER.
- SIZE is 32 or 64. STRUCTTYPE is the name of the struct from
- elf/external.h: Ehdr, Shdr, etc. FIELD is the name of a field in
- the struct. TYPE is the type of the field in the struct: Elf_Half,
- Elf_Word, or Elf_Addr. */
- #define ELF_FETCH_SIZED_FIELD(TYPEFUNCS, SIZE, STRUCTTYPE, BUFFER, \
- FIELD, TYPE) \
- ELF_FETCH_STRUCT_FIELD (TYPEFUNCS, \
- Elf ## SIZE ## _External_ ## STRUCTTYPE, \
- FIELD, BUFFER, TYPE)
- /* Like ELF_FETCH_SIZED_FIELD but taking an ELFCLASS value. */
- #define ELF_FETCH_FIELD(TYPEFUNCS, CLASS, STRUCTTYPE, BUFFER, \
- FIELD, TYPE) \
- ((CLASS) == ELFCLASS32 \
- ? ELF_FETCH_SIZED_FIELD (TYPEFUNCS, 32, STRUCTTYPE, BUFFER, FIELD, \
- TYPE) \
- : ELF_FETCH_SIZED_FIELD (TYPEFUNCS, 64, STRUCTTYPE, BUFFER, FIELD, \
- TYPE))
- /* Hideous macro to set the value of a field in an external ELF
- structure to VAL. TYPEFUNCS is the set of type functions. BUFFER
- points to the external data. STRUCTTYPE is the appropriate
- structure type. FIELD is a field within the struct. TYPE is the
- type of the field in the struct: Elf_Half, Elf_Word, or
- Elf_Addr. */
- #define ELF_SET_STRUCT_FIELD(TYPEFUNCS, STRUCTTYPE, FIELD, BUFFER, TYPE, VAL) \
- (TYPEFUNCS)->set_ ## TYPE ((BUFFER) + offsetof (STRUCTTYPE, FIELD), (VAL))
- /* Even more hideous macro to set the value of FIELD in BUFFER to VAL.
- SIZE is 32 or 64. STRUCTTYPE is the name of the struct from
- elf/external.h: Ehdr, Shdr, etc. FIELD is the name of a field in
- the struct. TYPE is the type of the field in the struct: Elf_Half,
- Elf_Word, or Elf_Addr. */
- #define ELF_SET_SIZED_FIELD(TYPEFUNCS, SIZE, STRUCTTYPE, BUFFER, FIELD, \
- TYPE, VAL) \
- ELF_SET_STRUCT_FIELD (TYPEFUNCS, \
- Elf ## SIZE ## _External_ ## STRUCTTYPE, \
- FIELD, BUFFER, TYPE, VAL)
- /* Like ELF_SET_SIZED_FIELD but taking an ELFCLASS value. */
- #define ELF_SET_FIELD(TYPEFUNCS, CLASS, STRUCTTYPE, BUFFER, FIELD, \
- TYPE, VAL) \
- ((CLASS) == ELFCLASS32 \
- ? ELF_SET_SIZED_FIELD (TYPEFUNCS, 32, STRUCTTYPE, BUFFER, FIELD, \
- TYPE, VAL) \
- : ELF_SET_SIZED_FIELD (TYPEFUNCS, 64, STRUCTTYPE, BUFFER, FIELD, \
- TYPE, VAL))
- /* Private data for an simple_object_read. */
- struct simple_object_elf_read
- {
- /* Type functions. */
- const struct elf_type_functions* type_functions;
- /* Elf data. */
- unsigned char ei_data;
- /* Elf class. */
- unsigned char ei_class;
- /* ELF OS ABI. */
- unsigned char ei_osabi;
- /* Elf machine number. */
- unsigned short machine;
- /* Processor specific flags. */
- unsigned int flags;
- /* File offset of section headers. */
- ulong_type shoff;
- /* Number of sections. */
- unsigned int shnum;
- /* Index of string table section header. */
- unsigned int shstrndx;
- };
- /* Private data for an simple_object_attributes. */
- struct simple_object_elf_attributes
- {
- /* Type functions. */
- const struct elf_type_functions* type_functions;
- /* Elf data. */
- unsigned char ei_data;
- /* Elf class. */
- unsigned char ei_class;
- /* ELF OS ABI. */
- unsigned char ei_osabi;
- /* Elf machine number. */
- unsigned short machine;
- /* Processor specific flags. */
- unsigned int flags;
- };
- /* Private data for an simple_object_write. */
- struct simple_object_elf_write
- {
- struct simple_object_elf_attributes attrs;
- unsigned char *shdrs;
- };
- /* See if we have an ELF file. */
- static void *
- simple_object_elf_match (unsigned char header[SIMPLE_OBJECT_MATCH_HEADER_LEN],
- int descriptor, off_t offset,
- const char *segment_name ATTRIBUTE_UNUSED,
- const char **errmsg, int *err)
- {
- unsigned char ei_data;
- unsigned char ei_class;
- const struct elf_type_functions *type_functions;
- unsigned char ehdr[sizeof (Elf64_External_Ehdr)];
- struct simple_object_elf_read *eor;
- if (header[EI_MAG0] != ELFMAG0
- || header[EI_MAG1] != ELFMAG1
- || header[EI_MAG2] != ELFMAG2
- || header[EI_MAG3] != ELFMAG3
- || header[EI_VERSION] != EV_CURRENT)
- {
- *errmsg = NULL;
- *err = 0;
- return NULL;
- }
- ei_data = header[EI_DATA];
- if (ei_data != ELFDATA2LSB && ei_data != ELFDATA2MSB)
- {
- *errmsg = "unknown ELF endianness";
- *err = 0;
- return NULL;
- }
- ei_class = header[EI_CLASS];
- switch (ei_class)
- {
- case ELFCLASS32:
- type_functions = (ei_data == ELFDATA2LSB
- ? &elf_little_32_functions
- : &elf_big_32_functions);
- break;
- case ELFCLASS64:
- #ifndef UNSIGNED_64BIT_TYPE
- *errmsg = "64-bit ELF objects not supported";
- *err = 0;
- return NULL;
- #else
- type_functions = (ei_data == ELFDATA2LSB
- ? &elf_little_64_functions
- : &elf_big_64_functions);
- break;
- #endif
- default:
- *errmsg = "unrecognized ELF size";
- *err = 0;
- return NULL;
- }
- if (!simple_object_internal_read (descriptor, offset, ehdr, sizeof ehdr,
- errmsg, err))
- return NULL;
- eor = XNEW (struct simple_object_elf_read);
- eor->type_functions = type_functions;
- eor->ei_data = ei_data;
- eor->ei_class = ei_class;
- eor->ei_osabi = header[EI_OSABI];
- eor->machine = ELF_FETCH_FIELD (type_functions, ei_class, Ehdr, ehdr,
- e_machine, Elf_Half);
- eor->flags = ELF_FETCH_FIELD (type_functions, ei_class, Ehdr, ehdr,
- e_flags, Elf_Word);
- eor->shoff = ELF_FETCH_FIELD (type_functions, ei_class, Ehdr, ehdr,
- e_shoff, Elf_Addr);
- eor->shnum = ELF_FETCH_FIELD (type_functions, ei_class, Ehdr, ehdr,
- e_shnum, Elf_Half);
- eor->shstrndx = ELF_FETCH_FIELD (type_functions, ei_class, Ehdr, ehdr,
- e_shstrndx, Elf_Half);
- if ((eor->shnum == 0 || eor->shstrndx == SHN_XINDEX)
- && eor->shoff != 0)
- {
- unsigned char shdr[sizeof (Elf64_External_Shdr)];
- /* Object file has more than 0xffff sections. */
- if (!simple_object_internal_read (descriptor, offset + eor->shoff, shdr,
- (ei_class == ELFCLASS32
- ? sizeof (Elf32_External_Shdr)
- : sizeof (Elf64_External_Shdr)),
- errmsg, err))
- {
- XDELETE (eor);
- return NULL;
- }
- if (eor->shnum == 0)
- eor->shnum = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_size, Elf_Addr);
- if (eor->shstrndx == SHN_XINDEX)
- {
- eor->shstrndx = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_link, Elf_Word);
- /* Versions of the GNU binutils between 2.12 and 2.18 did
- not handle objects with more than SHN_LORESERVE sections
- correctly. All large section indexes were offset by
- 0x100. There is more information at
- http://sourceware.org/bugzilla/show_bug.cgi?id-5900 .
- Fortunately these object files are easy to detect, as the
- GNU binutils always put the section header string table
- near the end of the list of sections. Thus if the
- section header string table index is larger than the
- number of sections, then we know we have to subtract
- 0x100 to get the real section index. */
- if (eor->shstrndx >= eor->shnum
- && eor->shstrndx >= SHN_LORESERVE + 0x100)
- eor->shstrndx -= 0x100;
- }
- }
- if (eor->shstrndx >= eor->shnum)
- {
- *errmsg = "invalid ELF shstrndx >= shnum";
- *err = 0;
- XDELETE (eor);
- return NULL;
- }
-
- if (eor->shstrndx == 0)
- {
- *errmsg = "invalid ELF shstrndx == 0";
- *err = 0;
- XDELETE (eor);
- return NULL;
- }
-
- return (void *) eor;
- }
- /* Find all sections in an ELF file. */
- static const char *
- simple_object_elf_find_sections (simple_object_read *sobj,
- int (*pfn) (void *, const char *,
- off_t offset, off_t length),
- void *data,
- int *err)
- {
- struct simple_object_elf_read *eor =
- (struct simple_object_elf_read *) sobj->data;
- const struct elf_type_functions *type_functions = eor->type_functions;
- unsigned char ei_class = eor->ei_class;
- size_t shdr_size;
- unsigned int shnum;
- unsigned char *shdrs;
- const char *errmsg;
- unsigned char *shstrhdr;
- size_t name_size;
- off_t shstroff;
- unsigned char *names;
- unsigned int i;
- shdr_size = (ei_class == ELFCLASS32
- ? sizeof (Elf32_External_Shdr)
- : sizeof (Elf64_External_Shdr));
- /* Read the section headers. We skip section 0, which is not a
- useful section. */
- shnum = eor->shnum;
- shdrs = XNEWVEC (unsigned char, shdr_size * (shnum - 1));
- if (!simple_object_internal_read (sobj->descriptor,
- sobj->offset + eor->shoff + shdr_size,
- shdrs,
- shdr_size * (shnum - 1),
- &errmsg, err))
- {
- XDELETEVEC (shdrs);
- return errmsg;
- }
- /* Read the section names. */
- shstrhdr = shdrs + (eor->shstrndx - 1) * shdr_size;
- name_size = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shstrhdr, sh_size, Elf_Addr);
- shstroff = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shstrhdr, sh_offset, Elf_Addr);
- names = XNEWVEC (unsigned char, name_size);
- if (!simple_object_internal_read (sobj->descriptor,
- sobj->offset + shstroff,
- names, name_size, &errmsg, err))
- {
- XDELETEVEC (names);
- XDELETEVEC (shdrs);
- return errmsg;
- }
- for (i = 1; i < shnum; ++i)
- {
- unsigned char *shdr;
- unsigned int sh_name;
- const char *name;
- off_t offset;
- off_t length;
- shdr = shdrs + (i - 1) * shdr_size;
- sh_name = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_name, Elf_Word);
- if (sh_name >= name_size)
- {
- *err = 0;
- XDELETEVEC (names);
- XDELETEVEC (shdrs);
- return "ELF section name out of range";
- }
- name = (const char *) names + sh_name;
- offset = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_offset, Elf_Addr);
- length = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_size, Elf_Addr);
- if (!(*pfn) (data, name, offset, length))
- break;
- }
- XDELETEVEC (names);
- XDELETEVEC (shdrs);
- return NULL;
- }
- /* Fetch the attributes for an simple_object_read. */
- static void *
- simple_object_elf_fetch_attributes (simple_object_read *sobj,
- const char **errmsg ATTRIBUTE_UNUSED,
- int *err ATTRIBUTE_UNUSED)
- {
- struct simple_object_elf_read *eor =
- (struct simple_object_elf_read *) sobj->data;
- struct simple_object_elf_attributes *ret;
- ret = XNEW (struct simple_object_elf_attributes);
- ret->type_functions = eor->type_functions;
- ret->ei_data = eor->ei_data;
- ret->ei_class = eor->ei_class;
- ret->ei_osabi = eor->ei_osabi;
- ret->machine = eor->machine;
- ret->flags = eor->flags;
- return ret;
- }
- /* Release the privata data for an simple_object_read. */
- static void
- simple_object_elf_release_read (void *data)
- {
- XDELETE (data);
- }
- /* Compare two attributes structures. */
- static const char *
- simple_object_elf_attributes_merge (void *todata, void *fromdata, int *err)
- {
- struct simple_object_elf_attributes *to =
- (struct simple_object_elf_attributes *) todata;
- struct simple_object_elf_attributes *from =
- (struct simple_object_elf_attributes *) fromdata;
- if (to->ei_data != from->ei_data || to->ei_class != from->ei_class)
- {
- *err = 0;
- return "ELF object format mismatch";
- }
- if (to->machine != from->machine)
- {
- int ok;
- /* EM_SPARC and EM_SPARC32PLUS are compatible and force an
- output of EM_SPARC32PLUS. */
- ok = 0;
- switch (to->machine)
- {
- case EM_SPARC:
- if (from->machine == EM_SPARC32PLUS)
- {
- to->machine = from->machine;
- ok = 1;
- }
- break;
- case EM_SPARC32PLUS:
- if (from->machine == EM_SPARC)
- ok = 1;
- break;
- default:
- break;
- }
- if (!ok)
- {
- *err = 0;
- return "ELF machine number mismatch";
- }
- }
- return NULL;
- }
- /* Release the private data for an attributes structure. */
- static void
- simple_object_elf_release_attributes (void *data)
- {
- XDELETE (data);
- }
- /* Prepare to write out a file. */
- static void *
- simple_object_elf_start_write (void *attributes_data,
- const char **errmsg ATTRIBUTE_UNUSED,
- int *err ATTRIBUTE_UNUSED)
- {
- struct simple_object_elf_attributes *attrs =
- (struct simple_object_elf_attributes *) attributes_data;
- struct simple_object_elf_write *ret;
- /* We're just going to record the attributes, but we need to make a
- copy because the user may delete them. */
- ret = XNEW (struct simple_object_elf_write);
- ret->attrs = *attrs;
- ret->shdrs = NULL;
- return ret;
- }
- /* Write out an ELF ehdr. */
- static int
- simple_object_elf_write_ehdr (simple_object_write *sobj, int descriptor,
- const char **errmsg, int *err)
- {
- struct simple_object_elf_attributes *attrs =
- (struct simple_object_elf_attributes *) sobj->data;
- const struct elf_type_functions* fns;
- unsigned char cl;
- size_t ehdr_size;
- unsigned char buf[sizeof (Elf64_External_Ehdr)];
- simple_object_write_section *section;
- unsigned int shnum;
- unsigned int shstrndx;
- fns = attrs->type_functions;
- cl = attrs->ei_class;
- shnum = 0;
- for (section = sobj->sections; section != NULL; section = section->next)
- ++shnum;
- if (shnum > 0)
- {
- /* Add a section header for the dummy section and one for
- .shstrtab. */
- shnum += 2;
- }
- ehdr_size = (cl == ELFCLASS32
- ? sizeof (Elf32_External_Ehdr)
- : sizeof (Elf64_External_Ehdr));
- memset (buf, 0, sizeof (Elf64_External_Ehdr));
- buf[EI_MAG0] = ELFMAG0;
- buf[EI_MAG1] = ELFMAG1;
- buf[EI_MAG2] = ELFMAG2;
- buf[EI_MAG3] = ELFMAG3;
- buf[EI_CLASS] = cl;
- buf[EI_DATA] = attrs->ei_data;
- buf[EI_VERSION] = EV_CURRENT;
- buf[EI_OSABI] = attrs->ei_osabi;
- ELF_SET_FIELD (fns, cl, Ehdr, buf, e_type, Elf_Half, ET_REL);
- ELF_SET_FIELD (fns, cl, Ehdr, buf, e_machine, Elf_Half, attrs->machine);
- ELF_SET_FIELD (fns, cl, Ehdr, buf, e_version, Elf_Word, EV_CURRENT);
- /* e_entry left as zero. */
- /* e_phoff left as zero. */
- ELF_SET_FIELD (fns, cl, Ehdr, buf, e_shoff, Elf_Addr, ehdr_size);
- ELF_SET_FIELD (fns, cl, Ehdr, buf, e_flags, Elf_Word, attrs->flags);
- ELF_SET_FIELD (fns, cl, Ehdr, buf, e_ehsize, Elf_Half, ehdr_size);
- ELF_SET_FIELD (fns, cl, Ehdr, buf, e_phentsize, Elf_Half,
- (cl == ELFCLASS32
- ? sizeof (Elf32_External_Phdr)
- : sizeof (Elf64_External_Phdr)));
- /* e_phnum left as zero. */
- ELF_SET_FIELD (fns, cl, Ehdr, buf, e_shentsize, Elf_Half,
- (cl == ELFCLASS32
- ? sizeof (Elf32_External_Shdr)
- : sizeof (Elf64_External_Shdr)));
- ELF_SET_FIELD (fns, cl, Ehdr, buf, e_shnum, Elf_Half,
- shnum >= SHN_LORESERVE ? 0 : shnum);
- if (shnum == 0)
- shstrndx = 0;
- else
- {
- shstrndx = shnum - 1;
- if (shstrndx >= SHN_LORESERVE)
- shstrndx = SHN_XINDEX;
- }
- ELF_SET_FIELD (fns, cl, Ehdr, buf, e_shstrndx, Elf_Half, shstrndx);
- return simple_object_internal_write (descriptor, 0, buf, ehdr_size,
- errmsg, err);
- }
- /* Write out an ELF shdr. */
- static int
- simple_object_elf_write_shdr (simple_object_write *sobj, int descriptor,
- off_t offset, unsigned int sh_name,
- unsigned int sh_type, unsigned int sh_flags,
- off_t sh_addr,
- unsigned int sh_offset, unsigned int sh_size,
- unsigned int sh_link, unsigned int sh_info,
- size_t sh_addralign,
- size_t sh_entsize,
- const char **errmsg, int *err)
- {
- struct simple_object_elf_attributes *attrs =
- (struct simple_object_elf_attributes *) sobj->data;
- const struct elf_type_functions* fns;
- unsigned char cl;
- size_t shdr_size;
- unsigned char buf[sizeof (Elf64_External_Shdr)];
- fns = attrs->type_functions;
- cl = attrs->ei_class;
- shdr_size = (cl == ELFCLASS32
- ? sizeof (Elf32_External_Shdr)
- : sizeof (Elf64_External_Shdr));
- memset (buf, 0, sizeof (Elf64_External_Shdr));
- ELF_SET_FIELD (fns, cl, Shdr, buf, sh_name, Elf_Word, sh_name);
- ELF_SET_FIELD (fns, cl, Shdr, buf, sh_type, Elf_Word, sh_type);
- ELF_SET_FIELD (fns, cl, Shdr, buf, sh_flags, Elf_Addr, sh_flags);
- ELF_SET_FIELD (fns, cl, Shdr, buf, sh_addr, Elf_Addr, sh_addr);
- ELF_SET_FIELD (fns, cl, Shdr, buf, sh_offset, Elf_Addr, sh_offset);
- ELF_SET_FIELD (fns, cl, Shdr, buf, sh_size, Elf_Addr, sh_size);
- ELF_SET_FIELD (fns, cl, Shdr, buf, sh_link, Elf_Word, sh_link);
- ELF_SET_FIELD (fns, cl, Shdr, buf, sh_info, Elf_Word, sh_info);
- ELF_SET_FIELD (fns, cl, Shdr, buf, sh_addralign, Elf_Addr, sh_addralign);
- ELF_SET_FIELD (fns, cl, Shdr, buf, sh_entsize, Elf_Addr, sh_entsize);
- return simple_object_internal_write (descriptor, offset, buf, shdr_size,
- errmsg, err);
- }
- /* Write out a complete ELF file.
- Ehdr
- initial dummy Shdr
- user-created Shdrs
- .shstrtab Shdr
- user-created section data
- .shstrtab data */
- static const char *
- simple_object_elf_write_to_file (simple_object_write *sobj, int descriptor,
- int *err)
- {
- struct simple_object_elf_write *eow =
- (struct simple_object_elf_write *) sobj->data;
- struct simple_object_elf_attributes *attrs = &eow->attrs;
- unsigned char cl;
- size_t ehdr_size;
- size_t shdr_size;
- const char *errmsg;
- simple_object_write_section *section;
- unsigned int shnum;
- size_t shdr_offset;
- size_t sh_offset;
- unsigned int first_sh_size;
- unsigned int first_sh_link;
- size_t sh_name;
- unsigned char zero;
- unsigned secnum;
- if (!simple_object_elf_write_ehdr (sobj, descriptor, &errmsg, err))
- return errmsg;
- cl = attrs->ei_class;
- if (cl == ELFCLASS32)
- {
- ehdr_size = sizeof (Elf32_External_Ehdr);
- shdr_size = sizeof (Elf32_External_Shdr);
- }
- else
- {
- ehdr_size = sizeof (Elf64_External_Ehdr);
- shdr_size = sizeof (Elf64_External_Shdr);
- }
- shnum = 0;
- for (section = sobj->sections; section != NULL; section = section->next)
- ++shnum;
- if (shnum == 0)
- return NULL;
- /* Add initial dummy Shdr and .shstrtab. */
- shnum += 2;
- shdr_offset = ehdr_size;
- sh_offset = shdr_offset + shnum * shdr_size;
- if (shnum < SHN_LORESERVE)
- first_sh_size = 0;
- else
- first_sh_size = shnum;
- if (shnum - 1 < SHN_LORESERVE)
- first_sh_link = 0;
- else
- first_sh_link = shnum - 1;
- if (!simple_object_elf_write_shdr (sobj, descriptor, shdr_offset,
- 0, 0, 0, 0, 0, first_sh_size, first_sh_link,
- 0, 0, 0, &errmsg, err))
- return errmsg;
- shdr_offset += shdr_size;
- sh_name = 1;
- secnum = 0;
- for (section = sobj->sections; section != NULL; section = section->next)
- {
- size_t mask;
- size_t new_sh_offset;
- size_t sh_size;
- struct simple_object_write_section_buffer *buffer;
- unsigned int sh_type = SHT_PROGBITS;
- unsigned int sh_flags = 0;
- off_t sh_addr = 0;
- unsigned int sh_link = 0;
- unsigned int sh_info = 0;
- size_t sh_addralign = 1U << section->align;
- size_t sh_entsize = 0;
- if (eow->shdrs)
- {
- sh_type = ELF_FETCH_FIELD (attrs->type_functions, attrs->ei_class, Shdr,
- eow->shdrs + secnum * shdr_size,
- sh_type, Elf_Word);
- sh_flags = ELF_FETCH_FIELD (attrs->type_functions, attrs->ei_class, Shdr,
- eow->shdrs + secnum * shdr_size,
- sh_flags, Elf_Addr);
- sh_addr = ELF_FETCH_FIELD (attrs->type_functions, attrs->ei_class, Shdr,
- eow->shdrs + secnum * shdr_size,
- sh_addr, Elf_Addr);
- sh_link = ELF_FETCH_FIELD (attrs->type_functions, attrs->ei_class, Shdr,
- eow->shdrs + secnum * shdr_size,
- sh_link, Elf_Word);
- sh_info = ELF_FETCH_FIELD (attrs->type_functions, attrs->ei_class, Shdr,
- eow->shdrs + secnum * shdr_size,
- sh_info, Elf_Word);
- sh_addralign = ELF_FETCH_FIELD (attrs->type_functions, attrs->ei_class, Shdr,
- eow->shdrs + secnum * shdr_size,
- sh_addralign, Elf_Addr);
- sh_entsize = ELF_FETCH_FIELD (attrs->type_functions, attrs->ei_class, Shdr,
- eow->shdrs + secnum * shdr_size,
- sh_entsize, Elf_Addr);
- secnum++;
- }
- mask = sh_addralign - 1;
- new_sh_offset = sh_offset + mask;
- new_sh_offset &= ~ mask;
- while (new_sh_offset > sh_offset)
- {
- unsigned char zeroes[16];
- size_t write;
- memset (zeroes, 0, sizeof zeroes);
- write = new_sh_offset - sh_offset;
- if (write > sizeof zeroes)
- write = sizeof zeroes;
- if (!simple_object_internal_write (descriptor, sh_offset, zeroes,
- write, &errmsg, err))
- return errmsg;
- sh_offset += write;
- }
- sh_size = 0;
- for (buffer = section->buffers; buffer != NULL; buffer = buffer->next)
- {
- if (!simple_object_internal_write (descriptor, sh_offset + sh_size,
- ((const unsigned char *)
- buffer->buffer),
- buffer->size, &errmsg, err))
- return errmsg;
- sh_size += buffer->size;
- }
- if (!simple_object_elf_write_shdr (sobj, descriptor, shdr_offset,
- sh_name, sh_type, sh_flags,
- sh_addr, sh_offset,
- sh_size, sh_link, sh_info,
- sh_addralign, sh_entsize,
- &errmsg, err))
- return errmsg;
- shdr_offset += shdr_size;
- sh_name += strlen (section->name) + 1;
- sh_offset += sh_size;
- }
- if (!simple_object_elf_write_shdr (sobj, descriptor, shdr_offset,
- sh_name, SHT_STRTAB, 0, 0, sh_offset,
- sh_name + strlen (".shstrtab") + 1, 0, 0,
- 1, 0, &errmsg, err))
- return errmsg;
- /* .shstrtab has a leading zero byte. */
- zero = 0;
- if (!simple_object_internal_write (descriptor, sh_offset, &zero, 1,
- &errmsg, err))
- return errmsg;
- ++sh_offset;
- for (section = sobj->sections; section != NULL; section = section->next)
- {
- size_t len;
- len = strlen (section->name) + 1;
- if (!simple_object_internal_write (descriptor, sh_offset,
- (const unsigned char *) section->name,
- len, &errmsg, err))
- return errmsg;
- sh_offset += len;
- }
- if (!simple_object_internal_write (descriptor, sh_offset,
- (const unsigned char *) ".shstrtab",
- strlen (".shstrtab") + 1, &errmsg, err))
- return errmsg;
- return NULL;
- }
- /* Release the private data for an simple_object_write structure. */
- static void
- simple_object_elf_release_write (void *data)
- {
- struct simple_object_elf_write *eow = (struct simple_object_elf_write *) data;
- if (eow->shdrs)
- XDELETE (eow->shdrs);
- XDELETE (data);
- }
- /* Copy all sections in an ELF file. */
- static const char *
- simple_object_elf_copy_lto_debug_sections (simple_object_read *sobj,
- simple_object_write *dobj,
- char *(*pfn) (const char *),
- int *err)
- {
- struct simple_object_elf_read *eor =
- (struct simple_object_elf_read *) sobj->data;
- const struct elf_type_functions *type_functions = eor->type_functions;
- struct simple_object_elf_write *eow =
- (struct simple_object_elf_write *) dobj->data;
- unsigned char ei_class = eor->ei_class;
- size_t shdr_size;
- unsigned int shnum;
- unsigned char *shdrs;
- const char *errmsg;
- unsigned char *shstrhdr;
- size_t name_size;
- off_t shstroff;
- unsigned char *names;
- unsigned int i;
- int changed;
- int *pfnret;
- const char **pfnname;
- unsigned new_i;
- unsigned *sh_map;
- unsigned first_shndx = 0;
- unsigned int *symtab_indices_shndx;
- shdr_size = (ei_class == ELFCLASS32
- ? sizeof (Elf32_External_Shdr)
- : sizeof (Elf64_External_Shdr));
- /* Read the section headers. We skip section 0, which is not a
- useful section. */
- shnum = eor->shnum;
- shdrs = XNEWVEC (unsigned char, shdr_size * (shnum - 1));
- if (!simple_object_internal_read (sobj->descriptor,
- sobj->offset + eor->shoff + shdr_size,
- shdrs,
- shdr_size * (shnum - 1),
- &errmsg, err))
- {
- XDELETEVEC (shdrs);
- return errmsg;
- }
- /* Read the section names. */
- shstrhdr = shdrs + (eor->shstrndx - 1) * shdr_size;
- name_size = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shstrhdr, sh_size, Elf_Addr);
- shstroff = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shstrhdr, sh_offset, Elf_Addr);
- names = XNEWVEC (unsigned char, name_size);
- if (!simple_object_internal_read (sobj->descriptor,
- sobj->offset + shstroff,
- names, name_size, &errmsg, err))
- {
- XDELETEVEC (names);
- XDELETEVEC (shdrs);
- return errmsg;
- }
- pfnret = XNEWVEC (int, shnum);
- pfnname = XNEWVEC (const char *, shnum);
- /* Map of symtab to index section. */
- symtab_indices_shndx = XCNEWVEC (unsigned int, shnum - 1);
- /* First perform the callbacks to know which sections to preserve and
- what name to use for those. */
- for (i = 1; i < shnum; ++i)
- {
- unsigned char *shdr;
- unsigned int sh_name, sh_type;
- const char *name;
- char *ret;
- shdr = shdrs + (i - 1) * shdr_size;
- sh_name = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_name, Elf_Word);
- if (sh_name >= name_size)
- {
- *err = 0;
- XDELETEVEC (names);
- XDELETEVEC (shdrs);
- return "ELF section name out of range";
- }
- name = (const char *) names + sh_name;
- ret = (*pfn) (name);
- pfnret[i - 1] = ret == NULL ? -1 : 0;
- pfnname[i - 1] = ret == NULL ? name : ret;
- if (first_shndx == 0
- && pfnret[i - 1] == 0)
- first_shndx = i;
- /* Remember the indexes of existing SHT_SYMTAB_SHNDX sections. */
- sh_type = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_type, Elf_Word);
- if (sh_type == SHT_SYMTAB_SHNDX)
- {
- unsigned int sh_link;
- sh_link = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_link, Elf_Word);
- symtab_indices_shndx[sh_link - 1] = i - 1;
- /* Always discard the extended index sections, after
- copying it will not be needed. This way we don't need to
- update it and deal with the ordering constraints of
- processing the existing symtab and changing the index. */
- pfnret[i - 1] = -1;
- }
- }
- /* Mark sections as preserved that are required by to be preserved
- sections. */
- do
- {
- changed = 0;
- for (i = 1; i < shnum; ++i)
- {
- unsigned char *shdr;
- unsigned int sh_type, sh_info, sh_link;
- off_t offset;
- off_t length;
- shdr = shdrs + (i - 1) * shdr_size;
- sh_type = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_type, Elf_Word);
- sh_info = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_info, Elf_Word);
- sh_link = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_link, Elf_Word);
- if (sh_type == SHT_GROUP)
- {
- /* Mark groups containing copied sections. */
- unsigned entsize = ELF_FETCH_FIELD (type_functions, ei_class,
- Shdr, shdr, sh_entsize,
- Elf_Addr);
- unsigned char *ent, *buf;
- int keep = 0;
- offset = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_offset, Elf_Addr);
- length = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_size, Elf_Addr);
- buf = XNEWVEC (unsigned char, length);
- if (!simple_object_internal_read (sobj->descriptor,
- sobj->offset + offset, buf,
- (size_t) length, &errmsg, err))
- {
- XDELETEVEC (buf);
- XDELETEVEC (names);
- XDELETEVEC (shdrs);
- return errmsg;
- }
- for (ent = buf + entsize; ent < buf + length; ent += entsize)
- {
- unsigned sec = type_functions->fetch_Elf_Word (ent);
- if (pfnret[sec - 1] == 0)
- keep = 1;
- }
- if (keep)
- {
- changed |= (pfnret[sh_link - 1] == -1
- || pfnret[i - 1] == -1);
- pfnret[sh_link - 1] = 0;
- pfnret[i - 1] = 0;
- }
- }
- if (sh_type == SHT_RELA
- || sh_type == SHT_REL)
- {
- /* Mark relocation sections and symtab of copied sections. */
- if (pfnret[sh_info - 1] == 0)
- {
- changed |= (pfnret[sh_link - 1] == -1
- || pfnret[i - 1] == -1);
- pfnret[sh_link - 1] = 0;
- pfnret[i - 1] = 0;
- }
- }
- if (sh_type == SHT_SYMTAB)
- {
- /* Mark strings sections of copied symtabs. */
- if (pfnret[i - 1] == 0)
- {
- changed |= pfnret[sh_link - 1] == -1;
- pfnret[sh_link - 1] = 0;
- }
- }
- }
- }
- while (changed);
- /* Compute a mapping of old -> new section numbers. */
- sh_map = XNEWVEC (unsigned, shnum);
- sh_map[0] = 0;
- new_i = 1;
- for (i = 1; i < shnum; ++i)
- {
- if (pfnret[i - 1] == -1)
- sh_map[i] = 0;
- else
- sh_map[i] = new_i++;
- }
- if (new_i - 1 >= SHN_LORESERVE)
- {
- *err = ENOTSUP;
- return "Too many copied sections";
- }
- eow->shdrs = XNEWVEC (unsigned char, shdr_size * (new_i - 1));
- /* Then perform the actual copying. */
- new_i = 0;
- for (i = 1; i < shnum; ++i)
- {
- unsigned char *shdr;
- unsigned int sh_name, sh_type;
- const char *name;
- off_t offset;
- off_t length;
- simple_object_write_section *dest;
- off_t flags;
- unsigned char *buf;
- if (pfnret[i - 1])
- continue;
- new_i++;
- shdr = shdrs + (i - 1) * shdr_size;
- sh_name = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_name, Elf_Word);
- if (sh_name >= name_size)
- {
- *err = 0;
- XDELETEVEC (names);
- XDELETEVEC (shdrs);
- XDELETEVEC (symtab_indices_shndx);
- return "ELF section name out of range";
- }
- name = pfnname[i - 1];
- offset = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_offset, Elf_Addr);
- length = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_size, Elf_Addr);
- sh_type = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_type, Elf_Word);
- dest = simple_object_write_create_section (dobj, pfnname[i - 1],
- 0, &errmsg, err);
- if (dest == NULL)
- {
- XDELETEVEC (names);
- XDELETEVEC (shdrs);
- XDELETEVEC (symtab_indices_shndx);
- return errmsg;
- }
- /* Record the SHDR of the source. */
- memcpy (eow->shdrs + (new_i - 1) * shdr_size, shdr, shdr_size);
- shdr = eow->shdrs + (new_i - 1) * shdr_size;
- /* Copy the data.
- ??? This is quite wasteful and ideally would be delayed until
- write_to_file (). Thus it questions the interfacing
- which eventually should contain destination creation plus
- writing. */
- buf = XNEWVEC (unsigned char, length);
- if (!simple_object_internal_read (sobj->descriptor,
- sobj->offset + offset, buf,
- (size_t) length, &errmsg, err))
- {
- XDELETEVEC (buf);
- XDELETEVEC (names);
- XDELETEVEC (shdrs);
- XDELETEVEC (symtab_indices_shndx);
- return errmsg;
- }
- /* If we are processing .symtab purge any symbols
- in discarded sections. */
- if (sh_type == SHT_SYMTAB)
- {
- unsigned entsize = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_entsize, Elf_Addr);
- size_t prevailing_name_idx = 0;
- unsigned char *ent;
- unsigned *shndx_table = NULL;
- /* Read the section index table if present. */
- if (symtab_indices_shndx[i - 1] != 0)
- {
- unsigned char *sidxhdr = shdrs + symtab_indices_shndx[i - 1] * shdr_size;
- off_t sidxoff = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- sidxhdr, sh_offset, Elf_Addr);
- size_t sidxsz = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- sidxhdr, sh_size, Elf_Addr);
- unsigned int shndx_type
- = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- sidxhdr, sh_type, Elf_Word);
- if (shndx_type != SHT_SYMTAB_SHNDX)
- return "Wrong section type of a SYMTAB SECTION INDICES section";
- shndx_table = (unsigned *)XNEWVEC (char, sidxsz);
- simple_object_internal_read (sobj->descriptor,
- sobj->offset + sidxoff,
- (unsigned char *)shndx_table,
- sidxsz, &errmsg, err);
- }
- /* Find a WEAK HIDDEN symbol which name we will use for removed
- symbols. We know there's a prevailing weak hidden symbol
- at the start of the .debug_info section. */
- for (ent = buf; ent < buf + length; ent += entsize)
- {
- unsigned st_shndx = ELF_FETCH_FIELD (type_functions, ei_class,
- Sym, ent,
- st_shndx, Elf_Half);
- unsigned char *st_info;
- unsigned char *st_other;
- if (ei_class == ELFCLASS32)
- {
- st_info = &((Elf32_External_Sym *)ent)->st_info;
- st_other = &((Elf32_External_Sym *)ent)->st_other;
- }
- else
- {
- st_info = &((Elf64_External_Sym *)ent)->st_info;
- st_other = &((Elf64_External_Sym *)ent)->st_other;
- }
- if (st_shndx == SHN_XINDEX)
- st_shndx = type_functions->fetch_Elf_Word
- ((unsigned char *)(shndx_table + (ent - buf) / entsize));
- if (st_shndx != SHN_COMMON
- && !(st_shndx != SHN_UNDEF
- && st_shndx < shnum
- && pfnret[st_shndx - 1] == -1)
- && ELF_ST_BIND (*st_info) == STB_WEAK
- && *st_other == STV_HIDDEN)
- {
- prevailing_name_idx = ELF_FETCH_FIELD (type_functions,
- ei_class, Sym, ent,
- st_name, Elf_Word);
- break;
- }
- }
- for (ent = buf; ent < buf + length; ent += entsize)
- {
- unsigned st_shndx = ELF_FETCH_FIELD (type_functions, ei_class,
- Sym, ent,
- st_shndx, Elf_Half);
- unsigned raw_st_shndx = st_shndx;
- unsigned char *st_info;
- unsigned char *st_other;
- int discard = 0;
- if (ei_class == ELFCLASS32)
- {
- st_info = &((Elf32_External_Sym *)ent)->st_info;
- st_other = &((Elf32_External_Sym *)ent)->st_other;
- }
- else
- {
- st_info = &((Elf64_External_Sym *)ent)->st_info;
- st_other = &((Elf64_External_Sym *)ent)->st_other;
- }
- if (st_shndx == SHN_XINDEX)
- st_shndx = type_functions->fetch_Elf_Word
- ((unsigned char *)(shndx_table + (ent - buf) / entsize));
- /* Eliminate all COMMONs - this includes __gnu_lto_slim
- which otherwise cause endless LTO plugin invocation.
- FIXME: remove the condition once we remove emission
- of __gnu_lto_slim symbol. */
- if (st_shndx == SHN_COMMON)
- discard = 1;
- /* We also need to remove symbols refering to sections
- we'll eventually remove as with fat LTO objects
- we otherwise get duplicate symbols at final link
- (with GNU ld, gold is fine and ignores symbols in
- sections marked as EXCLUDE). ld/20513 */
- else if (st_shndx != SHN_UNDEF
- && st_shndx < shnum
- && pfnret[st_shndx - 1] == -1)
- discard = 1;
- /* We also need to remove global UNDEFs which can
- cause link fails later. */
- else if (st_shndx == SHN_UNDEF
- && ELF_ST_BIND (*st_info) == STB_GLOBAL)
- discard = 1;
- if (discard)
- {
- /* Make discarded symbols undefined and unnamed
- in case it is local. */
- int bind = ELF_ST_BIND (*st_info);
- int other = STV_DEFAULT;
- if (bind == STB_LOCAL)
- {
- /* Make discarded local symbols unnamed and
- defined in the first prevailing section. */
- ELF_SET_FIELD (type_functions, ei_class, Sym,
- ent, st_name, Elf_Word, 0);
- ELF_SET_FIELD (type_functions, ei_class, Sym,
- ent, st_shndx, Elf_Half,
- sh_map[first_shndx]);
- }
- else
- {
- /* Make discarded global symbols hidden weak
- undefined and sharing a name of a prevailing
- symbol. */
- bind = STB_WEAK;
- other = STV_HIDDEN;
- ELF_SET_FIELD (type_functions, ei_class, Sym,
- ent, st_name, Elf_Word,
- prevailing_name_idx);
- ELF_SET_FIELD (type_functions, ei_class, Sym,
- ent, st_shndx, Elf_Half, SHN_UNDEF);
- }
- *st_other = other;
- *st_info = ELF_ST_INFO (bind, STT_NOTYPE);
- ELF_SET_FIELD (type_functions, ei_class, Sym,
- ent, st_value, Elf_Addr, 0);
- ELF_SET_FIELD (type_functions, ei_class, Sym,
- ent, st_size, Elf_Word, 0);
- }
- else if (raw_st_shndx < SHN_LORESERVE
- || raw_st_shndx == SHN_XINDEX)
- /* Remap the section reference. */
- ELF_SET_FIELD (type_functions, ei_class, Sym,
- ent, st_shndx, Elf_Half, sh_map[st_shndx]);
- }
- XDELETEVEC (shndx_table);
- }
- else if (sh_type == SHT_GROUP)
- {
- /* Remap section indices in groups and remove removed members. */
- unsigned char *ent, *dst;
- for (dst = ent = buf + 4; ent < buf + length; ent += 4)
- {
- unsigned shndx = type_functions->fetch_Elf_Word (ent);
- if (pfnret[shndx - 1] == -1)
- ;
- else
- {
- type_functions->set_Elf_Word (dst, sh_map[shndx]);
- dst += 4;
- }
- }
- /* Adjust the length. */
- length = dst - buf;
- }
- errmsg = simple_object_write_add_data (dobj, dest,
- buf, length, 1, err);
- XDELETEVEC (buf);
- if (errmsg)
- {
- XDELETEVEC (names);
- XDELETEVEC (shdrs);
- XDELETEVEC (symtab_indices_shndx);
- return errmsg;
- }
- flags = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_flags, Elf_Addr);
- /* Remap the section references. */
- {
- unsigned int sh_info, sh_link;
- if (flags & SHF_INFO_LINK || sh_type == SHT_REL || sh_type == SHT_RELA)
- {
- sh_info = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_info, Elf_Word);
- if (sh_info < SHN_LORESERVE
- || sh_info > SHN_HIRESERVE)
- sh_info = sh_map[sh_info];
- ELF_SET_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_info, Elf_Word, sh_info);
- }
- sh_link = ELF_FETCH_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_link, Elf_Word);
- if (sh_link < SHN_LORESERVE
- || sh_link > SHN_HIRESERVE)
- sh_link = sh_map[sh_link];
- ELF_SET_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_link, Elf_Word, sh_link);
- }
- /* The debugobj doesn't contain any code, thus no trampolines.
- Even when the original object needs trampolines, debugobj
- doesn't. */
- if (strcmp (name, ".note.GNU-stack") == 0)
- flags &= ~SHF_EXECINSTR;
- /* Clear SHF_EXCLUDE on to be preserved sections. */
- flags &= ~SHF_EXCLUDE;
- ELF_SET_FIELD (type_functions, ei_class, Shdr,
- shdr, sh_flags, Elf_Addr, flags);
- }
- XDELETEVEC (names);
- XDELETEVEC (shdrs);
- XDELETEVEC (pfnret);
- XDELETEVEC (pfnname);
- XDELETEVEC (symtab_indices_shndx);
- XDELETEVEC (sh_map);
- return NULL;
- }
- /* The ELF functions. */
- const struct simple_object_functions simple_object_elf_functions =
- {
- simple_object_elf_match,
- simple_object_elf_find_sections,
- simple_object_elf_fetch_attributes,
- simple_object_elf_release_read,
- simple_object_elf_attributes_merge,
- simple_object_elf_release_attributes,
- simple_object_elf_start_write,
- simple_object_elf_write_to_file,
- simple_object_elf_release_write,
- simple_object_elf_copy_lto_debug_sections
- };
|