diff options
Diffstat (limited to 'frida_mode/src/lib/lib.c')
| -rw-r--r-- | frida_mode/src/lib/lib.c | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/frida_mode/src/lib/lib.c b/frida_mode/src/lib/lib.c new file mode 100644 index 00000000..c5045533 --- /dev/null +++ b/frida_mode/src/lib/lib.c @@ -0,0 +1,176 @@ +#ifndef __APPLE__ + #include <elf.h> + #include <fcntl.h> + #include <limits.h> + #include <stdio.h> + #include <sys/mman.h> + #include <unistd.h> + + #include "frida-gum.h" + + #include "debug.h" + + #include "lib.h" + + #if defined(__arm__) || defined(__i386__) + #define ELFCLASS ELFCLASS32 +typedef Elf32_Ehdr Elf_Ehdr; +typedef Elf32_Phdr Elf_Phdr; +typedef Elf32_Shdr Elf_Shdr; +typedef Elf32_Addr Elf_Addr; + #elif defined(__aarch64__) || defined(__x86_64__) + #define ELFCLASS ELFCLASS64 +typedef Elf64_Ehdr Elf_Ehdr; +typedef Elf64_Phdr Elf_Phdr; +typedef Elf64_Shdr Elf_Shdr; +typedef Elf64_Addr Elf_Addr; + #else + #error "Unsupported platform" + #endif + +typedef struct { + + gchar name[PATH_MAX + 1]; + gchar path[PATH_MAX + 1]; + GumAddress base_address; + gsize size; + +} lib_details_t; + +static guint64 text_base = 0; +static guint64 text_limit = 0; + +static gboolean lib_find_exe(const GumModuleDetails *details, + gpointer user_data) { + + lib_details_t *lib_details = (lib_details_t *)user_data; + + memcpy(lib_details->name, details->name, PATH_MAX); + memcpy(lib_details->path, details->path, PATH_MAX); + lib_details->base_address = details->range->base_address; + lib_details->size = details->range->size; + return FALSE; + +} + +static void lib_validate_hdr(Elf_Ehdr *hdr) { + + if (hdr->e_ident[0] != ELFMAG0) FATAL("Invalid e_ident[0]"); + if (hdr->e_ident[1] != ELFMAG1) FATAL("Invalid e_ident[1]"); + if (hdr->e_ident[2] != ELFMAG2) FATAL("Invalid e_ident[2]"); + if (hdr->e_ident[3] != ELFMAG3) FATAL("Invalid e_ident[3]"); + if (hdr->e_ident[4] != ELFCLASS) FATAL("Invalid class"); + +} + +static void lib_read_text_section(lib_details_t *lib_details, Elf_Ehdr *hdr) { + + Elf_Phdr *phdr; + gboolean found_preferred_base = FALSE; + Elf_Addr preferred_base; + Elf_Shdr *shdr; + Elf_Shdr *shstrtab; + char * shstr; + char * section_name; + Elf_Shdr *curr; + char text_name[] = ".text"; + + phdr = (Elf_Phdr *)((char *)hdr + hdr->e_phoff); + for (size_t i = 0; i < hdr->e_phnum; i++) { + + if (phdr[i].p_type == PT_LOAD) { + + preferred_base = phdr[i].p_vaddr; + found_preferred_base = TRUE; + break; + + } + + } + + if (!found_preferred_base) { FATAL("Failed to find preferred load address"); } + + OKF("Image preferred load address 0x%016lx", preferred_base); + + shdr = (Elf_Shdr *)((char *)hdr + hdr->e_shoff); + shstrtab = &shdr[hdr->e_shstrndx]; + shstr = (char *)hdr + shstrtab->sh_offset; + + OKF("shdr: %p", shdr); + OKF("shstrtab: %p", shstrtab); + OKF("shstr: %p", shstr); + + for (size_t i = 0; i < hdr->e_shnum; i++) { + + curr = &shdr[i]; + + if (curr->sh_name == 0) continue; + + section_name = &shstr[curr->sh_name]; + OKF("Section: %2lu - base: 0x%016lX size: 0x%016lX %s", i, curr->sh_addr, + curr->sh_size, section_name); + if (memcmp(section_name, text_name, sizeof(text_name)) == 0 && + text_base == 0) { + + text_base = lib_details->base_address + curr->sh_addr - preferred_base; + text_limit = text_base + curr->sh_size; + OKF("> text_addr: 0x%016lX", text_base); + OKF("> text_limit: 0x%016lX", text_limit); + + } + + } + +} + +static void lib_get_text_section(lib_details_t *details) { + + int fd = -1; + off_t len; + Elf_Ehdr *hdr; + + fd = open(details->path, O_RDONLY); + if (fd < 0) { FATAL("Failed to open %s", details->path); } + + len = lseek(fd, 0, SEEK_END); + + if (len == (off_t)-1) { FATAL("Failed to lseek %s", details->path); } + + OKF("len: %ld", len); + + hdr = (Elf_Ehdr *)mmap(NULL, len, PROT_READ, MAP_PRIVATE, fd, 0); + if (hdr == MAP_FAILED) { FATAL("Failed to map %s", details->path); } + + lib_validate_hdr(hdr); + lib_read_text_section(details, hdr); + + munmap(hdr, len); + close(fd); + +} + +void lib_init(void) { + + lib_details_t lib_details; + gum_process_enumerate_modules(lib_find_exe, &lib_details); + OKF("Executable: 0x%016lx - %s", lib_details.base_address, lib_details.path); + lib_get_text_section(&lib_details); + +} + +guint64 lib_get_text_base(void) { + + if (text_base == 0) FATAL("Lib not initialized"); + return text_base; + +} + +guint64 lib_get_text_limit(void) { + + if (text_limit == 0) FATAL("Lib not initialized"); + return text_limit; + +} + +#endif + |