drafting the got/plt changes
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@@ -9,6 +9,7 @@
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#include "types.h"
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#include "types.h"
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#include <dlfcn.h>
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#include <dlfcn.h>
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#include <elf.h>
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#include <errno.h>
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#include <errno.h>
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#include <fcntl.h>
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#include <fcntl.h>
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#include <gelf.h>
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#include <gelf.h>
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@@ -138,8 +139,9 @@ cleanup:
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return ret;
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return ret;
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}
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}
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static HiloadResult moduler_apply_module_patch(const char *module_name, const char *patch_name,
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static HiloadResult
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struct sc_array_memreg *memregs) {
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moduler_apply_module_patch(const char *module_name, const char *patch_name,
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struct sc_array_memreg *memregs) {
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MemoryRegionSpan patch_memory = memory_get_module_span(memregs, patch_name);
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MemoryRegionSpan patch_memory = memory_get_module_span(memregs, patch_name);
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void *patch_base = (void *)patch_memory.region_start;
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void *patch_base = (void *)patch_memory.region_start;
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@@ -157,13 +159,97 @@ static HiloadResult moduler_apply_module_patch(const char *module_name, const ch
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void *module_base = (void *)module_memory.region_start;
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void *module_base = (void *)module_memory.region_start;
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size_t module_size = module_memory.region_end - module_memory.region_start;
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size_t module_size = module_memory.region_end - module_memory.region_start;
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ElfW(Rela) *rela = NULL;
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ElfW(Sym) *symtab = NULL;
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char *strtab = NULL;
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size_t rela_size = 0;
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Elf *elf = NULL;
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Elf *elf = NULL;
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GElf_Phdr *dyn_sct = hi_elf_find_dynamic_segment(module_base, module_size, &elf);
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ElfW(Dyn) *dyn_sct =
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(void)dyn_sct;
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hi_elf_find_dynamic_segment(module_base, module_size, &elf);
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// TODO: cont
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for (ElfW(Dyn) *d = dyn_sct; d->d_tag != DT_NULL; d++) {
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switch (d->d_tag) {
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case DT_JMPREL:
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rela = (ElfW(Rela) *)d->d_un.d_ptr;
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break;
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case DT_PLTRELSZ:
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rela_size = d->d_un.d_val;
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break;
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case DT_SYMTAB:
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symtab = (ElfW(Sym)*)d->d_un.d_ptr;
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break;
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case DT_STRTAB:
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strtab = (char *)d->d_un.d_ptr;
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break;
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}
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}
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// Adjust relative pointers by adding the module base address
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if (rela && ((void *)rela < module_base ||
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(void *)rela >= (void *)((char *)module_base + module_size))) {
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rela = (ElfW(Rela) *)((char *)module_base + (uintptr_t)rela);
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}
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if (symtab &&
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((void *)symtab < module_base ||
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(void *)symtab >= (void *)((char *)module_base + module_size))) {
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symtab = (ElfW(Sym) *)((char *)module_base + (uintptr_t)symtab);
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}
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if (strtab &&
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((void *)strtab < module_base ||
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(void *)strtab >= (void *)((char *)module_base + module_size))) {
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strtab = (char *)module_base + (uintptr_t)strtab;
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}
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if (!rela || !symtab || !strtab || rela_size == 0) {
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log_error("Missing required dynamic information\n");
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elf_end(elf);
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return HILOAD_FAIL;
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}
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// Process relocations to find GOT entries
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int found_count = 0;
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size_t rela_count = rela_size / sizeof(ElfW(Rela));
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printf("Processing %zu relocations\n", rela_count);
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size_t num_symbols = 0;
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for (size_t i = 0; i < rela_count; i++) {
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ElfW(Rela)* r = &rela[i];
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int sym_idx = ElfW(R_SYM)(r->r_info);
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int rel_type = ElfW(R_TYPE)(r->r_info);
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// We're only interested in JMP_SLOT relocations (GOT entries for functions)
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if (rel_type != R_X86_64_JUMP_SLOT && rel_type != R_386_JMP_SLOT) {
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continue;
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}
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ElfW(Sym)* sym = &symtab[sym_idx];
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char* name = strtab + sym->st_name;
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/* // Calculate the GOT entry address */
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/* void** got_entry = (void**)((char*)module_base + r->r_offset); */
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/* // Check if this is a symbol we want to patch */
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/* for (int j = 0; j < num_symbols; j++) { */
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/* if (strcmp(symbols[j].name, name) == 0) { */
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/* symbols[j].got_entry = got_entry; */
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/* symbols[j].orig_addr = *got_entry; // Save the original function pointer */
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/* printf("Found GOT entry for '%s' at %p (points to %p)\n", */
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/* name, got_entry, *got_entry); */
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/* found_count++; */
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/* break; */
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/* } */
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/* } */
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}
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symbol_term_symbols(&symbols);
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symbol_term_symbols(&symbols);
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elf_end(elf);
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return ret;
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return ret;
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}
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}
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@@ -26,6 +26,8 @@ typedef struct HiSymbol {
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HiSymbolBind binding;
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HiSymbolBind binding;
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HiSymbolType type;
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HiSymbolType type;
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void *address;
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void *address;
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void **got_entry;
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void *orig_address;
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} HiSymbol;
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} HiSymbol;
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sc_array_def(HiSymbol, sym);
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sc_array_def(HiSymbol, sym);
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typedef struct sc_array_sym HiSymbols;
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typedef struct sc_array_sym HiSymbols;
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