Function parse_pe

src/pe_embed.cpp:103–160

        };

        PeView parse_pe(std::vector<std::uint8_t> raw) {
            PeView v;
            v.bytes = std::move(raw);
            if (v.bytes.size() < sizeof(IMAGE_DOS_HEADER)) throw Error("target PE too small for DOS header");

            auto* dos = reinterpret_cast<IMAGE_DOS_HEADER*>(v.bytes.data());
            if (dos->e_magic != kDosMagic) throw Error("target PE: bad DOS magic");

            v.nt_off = static_cast<std::size_t>(dos->e_lfanew);
            if (v.nt_off + sizeof(std::uint32_t) + sizeof(IMAGE_FILE_HEADER) > v.bytes.size()) throw Error("target PE: NT headers out of range");

            const std::uint32_t sig = *reinterpret_cast<std::uint32_t*>(v.bytes.data() + v.nt_off);
            if (sig != kPeMagic) throw Error("target PE: bad NT signature");

            v.file_hdr_off = v.nt_off + 4;
            auto* fh = reinterpret_cast<IMAGE_FILE_HEADER*>(v.bytes.data() + v.file_hdr_off);

            v.num_sections = fh->NumberOfSections;
            v.opt_hdr_off  = v.file_hdr_off + sizeof(IMAGE_FILE_HEADER);

            const std::uint16_t opt_magic = *reinterpret_cast<std::uint16_t*>(v.bytes.data() + v.opt_hdr_off);
            if (opt_magic == kOpt64) {
                v.is64 = true;
                if (v.opt_hdr_off + sizeof(IMAGE_OPTIONAL_HEADER64) > v.bytes.size()) throw Error("target PE: PE32+ optional header out of range");
                auto* o = reinterpret_cast<IMAGE_OPTIONAL_HEADER64*>(v.bytes.data() + v.opt_hdr_off);

                v.file_alignment      = o->FileAlignment;
                v.section_alignment   = o->SectionAlignment;
                v.size_of_headers     = o->SizeOfHeaders;
                v.size_of_image       = o->SizeOfImage;
                v.dll_characteristics = o->DllCharacteristics;
                v.image_base          = o->ImageBase;
                v.old_reloc_rva       = o->DataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC].VirtualAddress;
                v.old_reloc_size      = o->DataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC].Size;
            }
            else if (opt_magic == kOpt32) {
                if (v.opt_hdr_off + sizeof(IMAGE_OPTIONAL_HEADER32) > v.bytes.size()) throw Error("target PE: PE32 optional header out of range");
                auto* o = reinterpret_cast<IMAGE_OPTIONAL_HEADER32*>( v.bytes.data() + v.opt_hdr_off);
                
                v.file_alignment      = o->FileAlignment;
                v.section_alignment   = o->SectionAlignment;
                v.size_of_headers     = o->SizeOfHeaders;
                v.size_of_image       = o->SizeOfImage;
                v.dll_characteristics = o->DllCharacteristics;
                v.image_base          = o->ImageBase;
                v.old_reloc_rva       = o->DataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC].VirtualAddress;
                v.old_reloc_size      = o->DataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC].Size;
            } 
            else {
                throw Error(fmt::format("target PE: unknown OptionalHeader magic 0x{:04x}", opt_magic));
            }

            v.section_tbl_off = v.opt_hdr_off + fh->SizeOfOptionalHeader;
            if (v.section_tbl_off + v.num_sections * sizeof(IMAGE_SECTION_HEADER) > v.bytes.size()) throw Error("target PE: section table out of range");
            if (v.file_alignment == 0 || v.section_alignment == 0) throw Error("target PE: zero alignment values");

            return v;
        }