diff options
Diffstat (limited to 'rtemstoolkit/elftoolchain/libdwarf/libdwarf_reloc.c')
| -rw-r--r-- | rtemstoolkit/elftoolchain/libdwarf/libdwarf_reloc.c | 493 |
1 files changed, 493 insertions, 0 deletions
diff --git a/rtemstoolkit/elftoolchain/libdwarf/libdwarf_reloc.c b/rtemstoolkit/elftoolchain/libdwarf/libdwarf_reloc.c new file mode 100644 index 0000000..2b1ad72 --- /dev/null +++ b/rtemstoolkit/elftoolchain/libdwarf/libdwarf_reloc.c @@ -0,0 +1,493 @@ +/*- + * Copyright (c) 2010 Kai Wang + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include "_libdwarf.h" + +ELFTC_VCSID("$Id: libdwarf_reloc.c 3578 2017-09-14 02:21:28Z emaste $"); + +Dwarf_Unsigned +_dwarf_get_reloc_type(Dwarf_P_Debug dbg, int is64) +{ + + assert(dbg != NULL); + + switch (dbg->dbgp_isa) { + case DW_ISA_AARCH64: + return (is64 ? R_AARCH64_ABS64 : R_AARCH64_ABS32); + case DW_ISA_X86: + return (R_386_32); + case DW_ISA_X86_64: + return (is64 ? R_X86_64_64 : R_X86_64_32); + case DW_ISA_SPARC: + return (is64 ? R_SPARC_UA64 : R_SPARC_UA32); + case DW_ISA_PPC: + return (R_PPC_ADDR32); + case DW_ISA_ARM: + return (R_ARM_ABS32); + case DW_ISA_MIPS: + return (is64 ? R_MIPS_64 : R_MIPS_32); + case DW_ISA_RISCV: + return (is64 ? R_RISCV_64 : R_RISCV_32); + case DW_ISA_IA64: + return (is64 ? R_IA_64_DIR64LSB : R_IA_64_DIR32LSB); + default: + break; + } + return (0); /* NOT REACHED */ +} + +int +_dwarf_get_reloc_size(Dwarf_Debug dbg, Dwarf_Unsigned rel_type) +{ + + switch (dbg->dbg_machine) { + case EM_NONE: + break; + case EM_AARCH64: + if (rel_type == R_AARCH64_ABS32) + return (4); + else if (rel_type == R_AARCH64_ABS64) + return (8); + break; + case EM_ARM: + if (rel_type == R_ARM_ABS32) + return (4); + break; + case EM_386: + case EM_IAMCU: + if (rel_type == R_386_32) + return (4); + break; + case EM_X86_64: + if (rel_type == R_X86_64_32) + return (4); + else if (rel_type == R_X86_64_64) + return (8); + break; + case EM_SPARC: + if (rel_type == R_SPARC_UA32) + return (4); + else if (rel_type == R_SPARC_UA64) + return (8); + break; + case EM_PPC: + if (rel_type == R_PPC_ADDR32) + return (4); + break; + case EM_MIPS: + if (rel_type == R_MIPS_32) + return (4); + else if (rel_type == R_MIPS_64) + return (8); + break; + case EM_RISCV: + if (rel_type == R_RISCV_32) + return (4); + else if (rel_type == R_RISCV_64) + return (8); + break; + case EM_IA_64: + if (rel_type == R_IA_64_SECREL32LSB) + return (4); + else if (rel_type == R_IA_64_DIR64LSB) + return (8); + break; + default: + break; + } + + /* unknown relocation. */ + return (0); +} + +int +_dwarf_reloc_section_init(Dwarf_P_Debug dbg, Dwarf_Rel_Section *drsp, + Dwarf_P_Section ref, Dwarf_Error *error) +{ + Dwarf_Rel_Section drs; + char name[128]; + int pseudo; + + assert(dbg != NULL && drsp != NULL && ref != NULL); + + if ((drs = calloc(1, sizeof(struct _Dwarf_Rel_Section))) == NULL) { + DWARF_SET_ERROR(dbg, error, DW_DLE_MEMORY); + return (DW_DLE_MEMORY); + } + + drs->drs_ref = ref; + + /* + * FIXME The logic here is most likely wrong. It should + * be the ISA that determines relocation type. + */ + if (dbg->dbgp_flags & DW_DLC_SIZE_64) + drs->drs_addend = 1; + else + drs->drs_addend = 0; + + if (dbg->dbgp_flags & DW_DLC_SYMBOLIC_RELOCATIONS) + pseudo = 1; + else + pseudo = 0; + + snprintf(name, sizeof(name), "%s%s", + drs->drs_addend ? ".rela" : ".rel", ref->ds_name); + if (_dwarf_section_init(dbg, &drs->drs_ds, name, pseudo, error) != + DW_DLE_NONE) { + free(drs); + DWARF_SET_ERROR(dbg, error, DW_DLE_MEMORY); + return (DW_DLE_MEMORY); + } + + STAILQ_INIT(&drs->drs_dre); + STAILQ_INSERT_TAIL(&dbg->dbgp_drslist, drs, drs_next); + dbg->dbgp_drscnt++; + *drsp = drs; + + return (DW_DLE_NONE); +} + +void +_dwarf_reloc_section_free(Dwarf_P_Debug dbg, Dwarf_Rel_Section *drsp) +{ + Dwarf_Rel_Section drs, tdrs; + Dwarf_Rel_Entry dre, tdre; + + assert(dbg != NULL && drsp != NULL); + + if (*drsp == NULL) + return; + + STAILQ_FOREACH_SAFE(drs, &dbg->dbgp_drslist, drs_next, tdrs) { + if (drs != *drsp) + continue; + STAILQ_REMOVE(&dbg->dbgp_drslist, drs, _Dwarf_Rel_Section, + drs_next); + STAILQ_FOREACH_SAFE(dre, &drs->drs_dre, dre_next, tdre) { + STAILQ_REMOVE(&drs->drs_dre, dre, _Dwarf_Rel_Entry, + dre_next); + free(dre); + } + if ((dbg->dbgp_flags & DW_DLC_SYMBOLIC_RELOCATIONS) == 0) + _dwarf_section_free(dbg, &drs->drs_ds); + else { + if (drs->drs_ds->ds_name) + free(drs->drs_ds->ds_name); + free(drs->drs_ds); + } + free(drs); + *drsp = NULL; + dbg->dbgp_drscnt--; + break; + } +} + +int +_dwarf_reloc_entry_add(Dwarf_P_Debug dbg, Dwarf_Rel_Section drs, + Dwarf_P_Section ds, unsigned char type, unsigned char length, + Dwarf_Unsigned offset, Dwarf_Unsigned symndx, Dwarf_Unsigned addend, + const char *secname, Dwarf_Error *error) +{ + Dwarf_Rel_Entry dre; + Dwarf_Unsigned reloff; + int ret; + + assert(drs != NULL); + assert(offset <= ds->ds_size); + reloff = offset; + + /* + * If the DW_DLC_SYMBOLIC_RELOCATIONS flag is set or ElfXX_Rel + * is used instead of ELfXX_Rela, we need to write the addend + * in the storage unit to be relocated. Otherwise write 0 in the + * storage unit and the addend will be written into relocation + * section later. + */ + if ((dbg->dbgp_flags & DW_DLC_SYMBOLIC_RELOCATIONS) || + drs->drs_addend == 0) + ret = dbg->write_alloc(&ds->ds_data, &ds->ds_cap, &offset, + addend, length, error); + else + ret = dbg->write_alloc(&ds->ds_data, &ds->ds_cap, &offset, + 0, length, error); + if (ret != DW_DLE_NONE) + return (ret); + if (offset > ds->ds_size) + ds->ds_size = offset; + + if ((dre = calloc(1, sizeof(struct _Dwarf_Rel_Entry))) == NULL) { + DWARF_SET_ERROR(dbg, error, DW_DLE_MEMORY); + return (DW_DLE_MEMORY); + } + STAILQ_INSERT_TAIL(&drs->drs_dre, dre, dre_next); + dre->dre_type = type; + dre->dre_length = length; + dre->dre_offset = reloff; + dre->dre_symndx = symndx; + dre->dre_addend = addend; + dre->dre_secname = secname; + drs->drs_drecnt++; + + return (DW_DLE_NONE); +} + +int +_dwarf_reloc_entry_add_pair(Dwarf_P_Debug dbg, Dwarf_Rel_Section drs, + Dwarf_P_Section ds, unsigned char length, Dwarf_Unsigned offset, + Dwarf_Unsigned symndx, Dwarf_Unsigned esymndx, Dwarf_Unsigned symoff, + Dwarf_Unsigned esymoff, Dwarf_Error *error) +{ + Dwarf_Rel_Entry dre; + Dwarf_Unsigned reloff; + int ret; + + assert(drs != NULL); + assert(offset <= ds->ds_size); + assert(dbg->dbgp_flags & DW_DLC_SYMBOLIC_RELOCATIONS); + reloff = offset; + + /* Write net offset into section stream. */ + ret = dbg->write_alloc(&ds->ds_data, &ds->ds_cap, &offset, + esymoff - symoff, length, error); + if (ret != DW_DLE_NONE) + return (ret); + if (offset > ds->ds_size) + ds->ds_size = offset; + + if ((dre = calloc(2, sizeof(struct _Dwarf_Rel_Entry))) == NULL) { + DWARF_SET_ERROR(dbg, error, DW_DLE_MEMORY); + return (DW_DLE_MEMORY); + } + STAILQ_INSERT_TAIL(&drs->drs_dre, &dre[0], dre_next); + STAILQ_INSERT_TAIL(&drs->drs_dre, &dre[1], dre_next); + dre[0].dre_type = dwarf_drt_first_of_length_pair; + dre[0].dre_length = length; + dre[0].dre_offset = reloff; + dre[0].dre_symndx = symndx; + dre[0].dre_addend = 0; + dre[0].dre_secname = NULL; + dre[1].dre_type = dwarf_drt_second_of_length_pair; + dre[1].dre_length = length; + dre[1].dre_offset = reloff; + dre[1].dre_symndx = esymndx; + dre[1].dre_addend = 0; + dre[1].dre_secname = NULL; + drs->drs_drecnt += 2; + + return (DW_DLE_NONE); +} + +int +_dwarf_reloc_section_finalize(Dwarf_P_Debug dbg, Dwarf_Rel_Section drs, + Dwarf_Error *error) +{ + Dwarf_P_Section ds; + Dwarf_Unsigned unit; + int ret, size; + + assert(dbg != NULL && drs != NULL && drs->drs_ds != NULL && + drs->drs_ref != NULL); + + ds = drs->drs_ds; + + /* + * Calculate the size (in bytes) of the relocation section. + */ + if (dbg->dbgp_flags & DW_DLC_SIZE_64) + unit = drs->drs_addend ? sizeof(Elf64_Rela) : sizeof(Elf64_Rel); + else + unit = drs->drs_addend ? sizeof(Elf32_Rela) : sizeof(Elf32_Rel); + assert(ds->ds_size == 0); + size = drs->drs_drecnt * unit; + + /* + * Discard this relocation section if there is no entry in it. + */ + if (size == 0) { + _dwarf_reloc_section_free(dbg, &drs); + return (DW_DLE_NONE); + } + + /* + * If we are under stream mode, realloc the section data block to + * this size. + */ + if ((dbg->dbgp_flags & DW_DLC_SYMBOLIC_RELOCATIONS) == 0) { + ds->ds_cap = size; + if ((ds->ds_data = realloc(ds->ds_data, (size_t) ds->ds_cap)) == + NULL) { + DWARF_SET_ERROR(dbg, error, DW_DLE_MEMORY); + return (DW_DLE_MEMORY); + } + } + + /* + * Notify the application the creation of this relocation section. + * Note that the section link here should point to the .symtab + * section, we set it to 0 since we have no way to know .symtab + * section index. + */ + ret = _dwarf_pro_callback(dbg, ds->ds_name, size, + drs->drs_addend ? SHT_RELA : SHT_REL, 0, 0, drs->drs_ref->ds_ndx, + &ds->ds_symndx, NULL); + if (ret < 0) { + DWARF_SET_ERROR(dbg, error, DW_DLE_ELF_SECT_ERR); + return (DW_DLE_ELF_SECT_ERR); + } + ds->ds_ndx = ret; + + return (DW_DLE_NONE); +} + +int +_dwarf_reloc_section_gen(Dwarf_P_Debug dbg, Dwarf_Rel_Section drs, + Dwarf_Error *error) +{ + Dwarf_Rel_Entry dre; + Dwarf_P_Section ds; + Dwarf_Unsigned type; + int ret; + + assert((dbg->dbgp_flags & DW_DLC_SYMBOLIC_RELOCATIONS) == 0); + assert(drs->drs_ds != NULL && drs->drs_ds->ds_size == 0); + assert(!STAILQ_EMPTY(&drs->drs_dre)); + ds = drs->drs_ds; + + STAILQ_FOREACH(dre, &drs->drs_dre, dre_next) { + assert(dre->dre_length == 4 || dre->dre_length == 8); + type = _dwarf_get_reloc_type(dbg, dre->dre_length == 8); + if (dbg->dbgp_flags & DW_DLC_SIZE_64) { + /* Write r_offset (8 bytes) */ + ret = dbg->write_alloc(&ds->ds_data, &ds->ds_cap, + &ds->ds_size, dre->dre_offset, 8, error); + if (ret != DW_DLE_NONE) + return (ret); + /* Write r_info (8 bytes) */ + ret = dbg->write_alloc(&ds->ds_data, &ds->ds_cap, + &ds->ds_size, ELF64_R_INFO(dre->dre_symndx, type), + 8, error); + if (ret != DW_DLE_NONE) + return (ret); + /* Write r_addend (8 bytes) */ + if (drs->drs_addend) { + ret = dbg->write_alloc(&ds->ds_data, + &ds->ds_cap, &ds->ds_size, dre->dre_addend, + 8, error); + if (ret != DW_DLE_NONE) + return (ret); + } + } else { + /* Write r_offset (4 bytes) */ + ret = dbg->write_alloc(&ds->ds_data, &ds->ds_cap, + &ds->ds_size, dre->dre_offset, 4, error); + if (ret != DW_DLE_NONE) + return (ret); + /* Write r_info (4 bytes) */ + ret = dbg->write_alloc(&ds->ds_data, &ds->ds_cap, + &ds->ds_size, ELF32_R_INFO(dre->dre_symndx, type), + 4, error); + if (ret != DW_DLE_NONE) + return (ret); + /* Write r_addend (4 bytes) */ + if (drs->drs_addend) { + ret = dbg->write_alloc(&ds->ds_data, + &ds->ds_cap, &ds->ds_size, dre->dre_addend, + 4, error); + if (ret != DW_DLE_NONE) + return (ret); + } + } + } + assert(ds->ds_size == ds->ds_cap); + + return (DW_DLE_NONE); +} + +int +_dwarf_reloc_gen(Dwarf_P_Debug dbg, Dwarf_Error *error) +{ + Dwarf_Rel_Section drs; + Dwarf_Rel_Entry dre; + Dwarf_P_Section ds; + int ret; + + STAILQ_FOREACH(drs, &dbg->dbgp_drslist, drs_next) { + /* + * Update relocation entries: translate any section name + * reference to section symbol index. + */ + STAILQ_FOREACH(dre, &drs->drs_dre, dre_next) { + if (dre->dre_secname == NULL) + continue; + ds = _dwarf_pro_find_section(dbg, dre->dre_secname); + assert(ds != NULL && ds->ds_symndx != 0); + dre->dre_symndx = ds->ds_symndx; + } + + /* + * Generate ELF relocation section if we are under stream + * mode. + */ + if ((dbg->dbgp_flags & DW_DLC_SYMBOLIC_RELOCATIONS) == 0) { + ret = _dwarf_reloc_section_gen(dbg, drs, error); + if (ret != DW_DLE_NONE) + return (ret); + } + } + + return (DW_DLE_NONE); +} + +void +_dwarf_reloc_cleanup(Dwarf_P_Debug dbg) +{ + Dwarf_Rel_Section drs, tdrs; + Dwarf_Rel_Entry dre, tdre; + + assert(dbg != NULL && dbg->dbg_mode == DW_DLC_WRITE); + + STAILQ_FOREACH_SAFE(drs, &dbg->dbgp_drslist, drs_next, tdrs) { + STAILQ_REMOVE(&dbg->dbgp_drslist, drs, _Dwarf_Rel_Section, + drs_next); + free(drs->drs_drd); + STAILQ_FOREACH_SAFE(dre, &drs->drs_dre, dre_next, tdre) { + STAILQ_REMOVE(&drs->drs_dre, dre, _Dwarf_Rel_Entry, + dre_next); + free(dre); + } + if (dbg->dbgp_flags & DW_DLC_SYMBOLIC_RELOCATIONS) { + if (drs->drs_ds) { + if (drs->drs_ds->ds_name) + free(drs->drs_ds->ds_name); + free(drs->drs_ds); + } + } + free(drs); + } + dbg->dbgp_drscnt = 0; + dbg->dbgp_drspos = NULL; +} |