add: migrate source code of luahook

blcrack/patchelf/CMakeLists.txt

@@ -0,0 +1,15 @@
+set(PATCHELF patchelf)
+
+file(GLOB_RECURSE PATCHELF_SRCS
+        ${CMAKE_CURRENT_LIST_DIR}/*.h
+        ${CMAKE_CURRENT_LIST_DIR}/*.cc
+)
+add_executable(${PATCHELF} ${PATCHELF_SRCS})
+target_link_libraries(${PATCHELF} PRIVATE cxxopts::cxxopts)
+target_link_options(${PATCHELF} PRIVATE -Wl,--version-script=${CMAKE_CURRENT_LIST_DIR}/patchelf.map)
+
+if(CMAKE_SIZEOF_VOID_P EQUAL 8)
+    target_compile_definitions(${PATCHELF} PRIVATE USE_64)
+else()
+    target_compile_definitions(${PATCHELF} PRIVATE USE_32)
+endif()

blcrack/patchelf/patchelf.h

@@ -0,0 +1,303 @@
+#include <map>
+#include <memory>
+#include <optional>
+#include <set>
+#include <stdexcept>
+#include <string>
+#include <vector>
+
+#include "elf.h"
+
+using FileContents = std::shared_ptr<std::vector<unsigned char>>;
+
+#define ElfFileParams class Elf_Ehdr, class Elf_Phdr, class Elf_Shdr, class Elf_Addr, class Elf_Off, class Elf_Dyn, class Elf_Sym, class Elf_Versym, class Elf_Verdef, class Elf_Verdaux, class Elf_Verneed, class Elf_Vernaux, class Elf_Rel, class Elf_Rela, unsigned ElfClass
+#define ElfFileParamNames Elf_Ehdr, Elf_Phdr, Elf_Shdr, Elf_Addr, Elf_Off, Elf_Dyn, Elf_Sym, Elf_Versym, Elf_Verdef, Elf_Verdaux, Elf_Verneed, Elf_Vernaux, Elf_Rel, Elf_Rela, ElfClass
+
+template<class T>
+struct span
+{
+    explicit span(T* d = {}, size_t l = {}) : data(d), len(l) {}
+    span(T* from, T* to) : data(from), len(to-from) { assert(from <= to); }
+    T& operator[](std::size_t i) { checkRange(i); return data[i]; }
+    T* begin() { return data; }
+    T* end() { return data + len; }
+    auto size() const { return len; }
+    explicit operator bool() const { return size() > 0; }
+
+private:
+    void checkRange(std::size_t i) {
+        if (i >= size()) throw std::out_of_range("error: Span access out of range.");
+    }
+
+    T* data;
+    size_t len;
+};
+
+template<ElfFileParams>
+class ElfFile
+{
+public:
+
+    const FileContents fileContents;
+
+private:
+
+    std::vector<Elf_Phdr> phdrs;
+    std::vector<Elf_Shdr> shdrs;
+
+    bool littleEndian;
+
+    bool changed = false;
+
+    bool isExecutable = false;
+
+    using SectionName = std::string;
+    using ReplacedSections = std::map<SectionName, std::string>;
+
+    ReplacedSections replacedSections;
+
+    std::string sectionNames; /* content of the .shstrtab section */
+
+    /* Align on 4 or 8 bytes boundaries on 32- or 64-bit platforms
+       respectively. */
+    static constexpr size_t sectionAlignment = sizeof(Elf_Off);
+
+    std::vector<SectionName> sectionsByOldIndex;
+
+public:
+    explicit ElfFile(FileContents fileContents);
+
+    [[nodiscard]] bool isChanged() const noexcept
+    {
+        return changed;
+    }
+
+private:
+
+    struct CompPhdr
+    {
+        const ElfFile * elfFile;
+        bool operator ()(const Elf_Phdr & x, const Elf_Phdr & y) const noexcept
+        {
+            // A PHDR comes before everything else.
+            if (elfFile->rdi(y.p_type) == PT_PHDR) return false;
+            if (elfFile->rdi(x.p_type) == PT_PHDR) return true;
+
+            // Sort non-PHDRs by address.
+            return elfFile->rdi(x.p_paddr) < elfFile->rdi(y.p_paddr);
+        }
+    };
+
+    void sortPhdrs();
+
+    struct CompShdr
+    {
+        const ElfFile * elfFile;
+        bool operator ()(const Elf_Shdr & x, const Elf_Shdr & y) const noexcept
+        {
+            return elfFile->rdi(x.sh_offset) < elfFile->rdi(y.sh_offset);
+        }
+    };
+
+    [[nodiscard]] unsigned int getPageSize() const noexcept;
+
+    void sortShdrs();
+
+    void shiftFile(unsigned int extraPages, size_t sizeOffset, size_t extraBytes);
+
+    [[nodiscard]] std::string getSectionName(const Elf_Shdr & shdr) const;
+
+    const Elf_Shdr & findSectionHeader(const SectionName & sectionName) const;
+
+    [[nodiscard]] std::optional<std::reference_wrapper<const Elf_Shdr>> tryFindSectionHeader(const SectionName & sectionName) const;
+
+    template<class T> span<T> getSectionSpan(const Elf_Shdr & shdr) const;
+    template<class T> span<T> getSectionSpan(const SectionName & sectionName);
+    template<class T> span<T> tryGetSectionSpan(const SectionName & sectionName);
+
+    [[nodiscard]] unsigned int getSectionIndex(const SectionName & sectionName) const;
+
+    std::string & replaceSection(const SectionName & sectionName,
+        unsigned int size);
+
+    [[nodiscard]] bool hasReplacedSection(const SectionName & sectionName) const;
+    [[nodiscard]] bool canReplaceSection(const SectionName & sectionName) const;
+
+    void writeReplacedSections(Elf_Off & curOff,
+        Elf_Addr startAddr, Elf_Off startOffset);
+
+    void rewriteHeaders(Elf_Addr phdrAddress);
+
+    void rewriteSectionsLibrary();
+
+    void rewriteSectionsExecutable();
+
+    void normalizeNoteSegments();
+
+public:
+
+    void rewriteSections(bool force = false);
+
+    [[nodiscard]] std::string getInterpreter() const;
+
+    typedef enum { printOsAbi, replaceOsAbi } osAbiMode;
+
+    void modifyOsAbi(osAbiMode op, const std::string & newOsAbi);
+
+    typedef enum { printSoname, replaceSoname } sonameMode;
+
+    void modifySoname(sonameMode op, const std::string & newSoname);
+
+    void setInterpreter(const std::string & newInterpreter);
+
+    typedef enum { rpPrint, rpShrink, rpSet, rpAdd, rpRemove } RPathOp;
+
+    void modifyRPath(RPathOp op, const std::vector<std::string> & allowedRpathPrefixes, std::string newRPath);
+    std::string shrinkRPath(char* rpath, std::vector<std::string> &neededLibs, const std::vector<std::string> & allowedRpathPrefixes);
+    void removeRPath(Elf_Shdr & shdrDynamic);
+
+    void addNeeded(const std::set<std::string> & libs);
+
+    void removeNeeded(const std::set<std::string> & libs);
+
+    void replaceNeeded(const std::map<std::string, std::string> & libs);
+
+    void printNeededLibs() const;
+
+    void noDefaultLib();
+
+    void addDebugTag();
+
+    void renameDynamicSymbols(const std::unordered_map<std::string_view, std::string>&);
+
+    void clearSymbolVersions(const std::set<std::string> & syms);
+
+    enum class ExecstackMode { print, set, clear };
+
+    void modifyExecstack(ExecstackMode op);
+
+    std::vector<std::string> getNeededLibs() const;
+private:
+    struct GnuHashTable {
+        using BloomWord = Elf_Addr;
+        struct Header {
+            uint32_t numBuckets, symndx, maskwords, shift2;
+        } m_hdr;
+        span<BloomWord> m_bloomFilters;
+        span<uint32_t> m_buckets, m_table;
+    };
+    GnuHashTable parseGnuHashTable(span<char> gh);
+
+    struct HashTable {
+        struct Header {
+            uint32_t numBuckets, nchain;
+        } m_hdr;
+        span<uint32_t> m_buckets, m_chain;
+    };
+    HashTable parseHashTable(span<char> gh);
+
+    void rebuildGnuHashTable(span<char> strTab, span<Elf_Sym> dynsyms);
+    void rebuildHashTable(span<char> strTab, span<Elf_Sym> dynsyms);
+
+    using Elf_Rel_Info = decltype(Elf_Rel::r_info);
+
+    uint32_t rel_getSymId(const Elf_Rel_Info& info) const
+    {
+        if constexpr (std::is_same_v<Elf_Rel, Elf64_Rel>)
+            return ELF64_R_SYM(info);
+        else
+            return ELF32_R_SYM(info);
+    }
+
+    Elf_Rel_Info rel_setSymId(Elf_Rel_Info info, uint32_t id) const
+    {
+        if constexpr (std::is_same_v<Elf_Rel, Elf64_Rel>)
+        {
+            constexpr Elf_Rel_Info idmask = (~Elf_Rel_Info()) << 32;
+            info = (info & ~idmask) | (Elf_Rel_Info(id) << 32);
+        }
+        else
+        {
+            constexpr Elf_Rel_Info idmask = (~Elf_Rel_Info()) << 8;
+            info = (info & ~idmask) | (Elf_Rel_Info(id) << 8);
+        }
+        return info;
+    }
+
+    template<class ElfRelType, class RemapFn>
+    void changeRelocTableSymIds(const Elf_Shdr& shdr, RemapFn&& old2newSymId)
+    {
+        static_assert(std::is_same_v<ElfRelType, Elf_Rel> || std::is_same_v<ElfRelType, Elf_Rela>);
+
+        for (auto& r : getSectionSpan<ElfRelType>(shdr))
+        {
+            auto info = rdi(r.r_info);
+            auto oldSymIdx = rel_getSymId(info);
+            auto newSymIdx = old2newSymId(oldSymIdx);
+            if (newSymIdx != oldSymIdx)
+                wri(r.r_info, rel_setSymId(info, newSymIdx));
+        }
+    }
+
+    template<class StrIdxCallback>
+    void forAllStringReferences(const Elf_Shdr& strTabHdr, StrIdxCallback&& fn);
+
+    template<class T, class U>
+    auto follow(U* ptr, size_t offset) -> T* {
+        return offset ? (T*)(((char*)ptr)+offset) : nullptr;
+    };
+
+    template<class VdFn, class VaFn>
+    void forAll_ElfVer(span<Elf_Verdef> vdspan, VdFn&& vdfn, VaFn&& vafn)
+    {
+        auto* vd = vdspan.begin();
+        for (; vd; vd = follow<Elf_Verdef>(vd, rdi(vd->vd_next)))
+        {
+            vdfn(*vd);
+            auto va = follow<Elf_Verdaux>(vd, rdi(vd->vd_aux));
+            for (; va; va = follow<Elf_Verdaux>(va, rdi(va->vda_next)))
+                vafn(*va);
+        }
+    }
+
+    template<class VnFn, class VaFn>
+    void forAll_ElfVer(span<Elf_Verneed> vnspan, VnFn&& vnfn, VaFn&& vafn)
+    {
+        auto* vn = vnspan.begin();
+        for (; vn; vn = follow<Elf_Verneed>(vn, rdi(vn->vn_next)))
+        {
+            vnfn(*vn);
+            auto va = follow<Elf_Vernaux>(vn, rdi(vn->vn_aux));
+            for (; va; va = follow<Elf_Vernaux>(va, rdi(va->vna_next)))
+                vafn(*va);
+        }
+    }
+
+    /* Convert an integer in big or little endian representation (as
+       specified by the ELF header) to this platform's integer
+       representation. */
+    template<class I>
+    constexpr I rdi(I i) const noexcept;
+
+    /* Convert back to the ELF representation. */
+    template<class I, class U>
+    constexpr inline I wri(I & t, U i) const
+    {
+        I val = static_cast<I>(i);
+        if (static_cast<U>(val) != i)            
+            throw std::runtime_error { "value truncation" };
+        t = rdi(val);
+        return val;
+    }
+
+    [[nodiscard]] Elf_Ehdr *hdr() noexcept {
+      return reinterpret_cast<Elf_Ehdr *>(fileContents->data());
+    }
+
+    [[nodiscard]] const Elf_Ehdr *hdr() const noexcept {
+      return reinterpret_cast<const Elf_Ehdr *>(fileContents->data());
+    }
+};
+
+FileContents readFile(const std::string & fileName, size_t cutOff = std::numeric_limits<size_t>::max());
+void writeFile(const std::string & fileName, const FileContents & contents);

blcrack/patchelf/patchelf.map

@@ -0,0 +1,4 @@
+{
+  local: *
+  ;
+};