LibELF: Move validation methods to their own file

These validate_elf_* methods really had no business being static
methods of ELF::Image. Now that the ELF namespace exists, it makes
sense to just move them to be free functions in the namespace.

1 files changed, 1 insertions, 155 deletions

diff --git a/Libraries/LibELF/Image.cpp b/Libraries/LibELF/Image.cpp
index c265e3a9b8..eae3c11e16 100644
--- a/Libraries/LibELF/Image.cpp
+++ b/Libraries/LibELF/Image.cpp
@@ -28,6 +28,7 @@
 #include <AK/StringBuilder.h>
 #include <AK/StringView.h>
 #include <LibELF/Image.h>
+#include <LibELF/Validation.h>
 
 namespace ELF {
 
@@ -261,161 +262,6 @@ const Image::Section Image::lookup_section(const String& name) const
     return section(0);
 }
 
-bool Image::validate_elf_header(const Elf32_Ehdr& elf_header, size_t file_size)
-{
-    if (!IS_ELF(elf_header)) {
-        dbgputstr("File is not an ELF file.\n");
-        return false;
-    }
-
-    if (ELFCLASS32 != elf_header.e_ident[EI_CLASS]) {
-        dbgputstr("File is not a 32 bit ELF file.\n");
-        return false;
-    }
-
-    if (ELFDATA2LSB != elf_header.e_ident[EI_DATA]) {
-        dbgputstr("File is not a little endian ELF file.\n");
-        return false;
-    }
-
-    if (EV_CURRENT != elf_header.e_ident[EI_VERSION]) {
-        dbgprintf("File has unrecognized ELF version (%d), expected (%d)!\n", elf_header.e_ident[EI_VERSION], EV_CURRENT);
-        return false;
-    }
-
-    if (ELFOSABI_SYSV != elf_header.e_ident[EI_OSABI]) {
-        dbgprintf("File has unknown OS ABI (%d), expected SYSV(0)!\n", elf_header.e_ident[EI_OSABI]);
-        return false;
-    }
-
-    if (0 != elf_header.e_ident[EI_ABIVERSION]) {
-        dbgprintf("File has unknown SYSV ABI version (%d)!\n", elf_header.e_ident[EI_ABIVERSION]);
-        return false;
-    }
-
-    if (EM_386 != elf_header.e_machine) {
-        dbgprintf("File has unknown machine (%d), expected i386 (3)!\n", elf_header.e_machine);
-        return false;
-    }
-
-    if (ET_EXEC != elf_header.e_type && ET_DYN != elf_header.e_type && ET_REL != elf_header.e_type) {
-        dbgprintf("File has unloadable ELF type (%d), expected REL (1), EXEC (2) or DYN (3)!\n", elf_header.e_type);
-        return false;
-    }
-
-    if (EV_CURRENT != elf_header.e_version) {
-        dbgprintf("File has unrecognized ELF version (%d), expected (%d)!\n", elf_header.e_version, EV_CURRENT);
-        return false;
-    }
-
-    if (sizeof(Elf32_Ehdr) != elf_header.e_ehsize) {
-        dbgprintf("File has incorrect ELF header size..? (%d), expected (%d)!\n", elf_header.e_ehsize, sizeof(Elf32_Ehdr));
-        return false;
-    }
-
-    if (elf_header.e_phoff > file_size || elf_header.e_shoff > file_size) {
-        dbgprintf("SHENANIGANS! program header offset (%d) or section header offset (%d) are past the end of the file!\n",
-            elf_header.e_phoff, elf_header.e_shoff);
-        return false;
-    }
-
-    if (elf_header.e_phnum != 0 && elf_header.e_phoff != elf_header.e_ehsize) {
-        dbgprintf("File does not have program headers directly after the ELF header? program header offset (%d), expected (%d).\n",
-            elf_header.e_phoff, elf_header.e_ehsize);
-        return false;
-    }
-
-    if (0 != elf_header.e_flags) {
-        dbgprintf("File has incorrect ELF header flags...? (%d), expected (%d).\n", elf_header.e_flags, 0);
-        return false;
-    }
-
-    if (0 != elf_header.e_phnum && sizeof(Elf32_Phdr) != elf_header.e_phentsize) {
-        dbgprintf("File has incorrect program header size..? (%d), expected (%d).\n", elf_header.e_phentsize, sizeof(Elf32_Phdr));
-        return false;
-    }
-
-    if (sizeof(Elf32_Shdr) != elf_header.e_shentsize) {
-        dbgprintf("File has incorrect section header size..? (%d), expected (%d).\n", elf_header.e_shentsize, sizeof(Elf32_Shdr));
-        return false;
-    }
-
-    size_t end_of_last_program_header = elf_header.e_phoff + (elf_header.e_phnum * elf_header.e_phentsize);
-    if (end_of_last_program_header > file_size) {
-        dbgprintf("SHENANIGANS! End of last program header (%d) is past the end of the file!\n", end_of_last_program_header);
-        return false;
-    }
-
-    size_t end_of_last_section_header = elf_header.e_shoff + (elf_header.e_shnum * elf_header.e_shentsize);
-    if (end_of_last_section_header > file_size) {
-        dbgprintf("SHENANIGANS! End of last section header (%d) is past the end of the file!\n", end_of_last_section_header);
-        return false;
-    }
-
-    if (elf_header.e_shstrndx >= elf_header.e_shnum) {
-        dbgprintf("SHENANIGANS! Section header string table index (%d) is not a valid index given we have %d section headers!\n", elf_header.e_shstrndx, elf_header.e_shnum);
-        return false;
-    }
-
-    return true;
-}
-
-bool Image::validate_program_headers(const Elf32_Ehdr& elf_header, size_t file_size, u8* buffer, size_t buffer_size, String& interpreter_path)
-{
-    // Can we actually parse all the program headers in the given buffer?
-    size_t end_of_last_program_header = elf_header.e_phoff + (elf_header.e_phnum * elf_header.e_phentsize);
-    if (end_of_last_program_header > buffer_size) {
-        dbgprintf("Unable to parse program headers from buffer, buffer too small! Buffer size: %zu, End of program headers %zu\n",
-            buffer_size, end_of_last_program_header);
-        return false;
-    }
-
-    if (file_size < buffer_size) {
-        dbgputstr("We somehow read more from a file than was in the file in the first place!\n");
-        ASSERT_NOT_REACHED();
-    }
-
-    size_t num_program_headers = elf_header.e_phnum;
-    auto program_header_begin = (const Elf32_Phdr*)&(buffer[elf_header.e_phoff]);
-
-    for (size_t header_index = 0; header_index < num_program_headers; ++header_index) {
-        auto& program_header = program_header_begin[header_index];
-        switch (program_header.p_type) {
-        case PT_INTERP:
-            if (ET_DYN != elf_header.e_type) {
-                dbgprintf("Found PT_INTERP header (%d) in non-DYN ELF object! What? We can't handle this!\n", header_index);
-                return false;
-            }
-            // We checked above that file_size was >= buffer size. We only care about buffer size anyway, we're trying to read this!
-            if (program_header.p_offset + program_header.p_filesz > buffer_size) {
-                dbgprintf("Found PT_INTERP header (%d), but the .interp section was not within our buffer :( Your program will not be loaded today.\n", header_index);
-                return false;
-            }
-            interpreter_path = String((const char*)&buffer[program_header.p_offset], program_header.p_filesz - 1);
-            break;
-        case PT_LOAD:
-        case PT_DYNAMIC:
-        case PT_NOTE:
-        case PT_PHDR:
-        case PT_TLS:
-            if (program_header.p_offset + program_header.p_filesz > file_size) {
-                dbgprintf("SHENANIGANS! Program header %d segment leaks beyond end of file!\n", header_index);
-                return false;
-            }
-            if ((program_header.p_flags & PF_X) && (program_header.p_flags & PF_W)) {
-                dbgprintf("SHENANIGANS! Program header %d segment is marked write and execute\n", header_index);
-                return false;
-            }
-            break;
-        default:
-            // Not handling other program header types in other code so... let's not surprise them
-            dbgprintf("Found program header (%d) of unrecognized type %x!\n", header_index, program_header.p_type);
-            return false;
-        }
-    }
-    return true;
-}
-
 StringView Image::Symbol::raw_data() const
 {
     auto& section = this->section();