diff options
Diffstat (limited to 'winsup/cygwin/hookapi.cc')
| -rw-r--r-- | winsup/cygwin/hookapi.cc | 28 |
1 files changed, 22 insertions, 6 deletions
diff --git a/winsup/cygwin/hookapi.cc b/winsup/cygwin/hookapi.cc index 97e3330ee..8857b3f0e 100644 --- a/winsup/cygwin/hookapi.cc +++ b/winsup/cygwin/hookapi.cc @@ -23,10 +23,10 @@ struct function_hook static PIMAGE_NT_HEADERS PEHeaderFromHModule (HMODULE hModule) { - PIMAGE_NT_HEADERS pNTHeader = NULL; + PIMAGE_NT_HEADERS pNTHeader; if (PIMAGE_DOS_HEADER(hModule) ->e_magic != IMAGE_DOS_SIGNATURE) - /* nothing */; + pNTHeader = NULL; else { pNTHeader = PIMAGE_NT_HEADERS (PBYTE (hModule) @@ -38,6 +38,18 @@ PEHeaderFromHModule (HMODULE hModule) return pNTHeader; } +long +rvadelta (PIMAGE_NT_HEADERS pnt, long import_rva) +{ + PIMAGE_SECTION_HEADER section = (PIMAGE_SECTION_HEADER) (pnt + 1); + for (int i = 0; i < pnt->FileHeader.NumberOfSections; i++) + if (section[i].VirtualAddress <= import_rva + && (section[i].VirtualAddress + section[i].Misc.VirtualSize) >= import_rva) + // if (strncasematch ((char *) section[i].Name, ".idata", IMAGE_SIZEOF_SHORT_NAME)) + return section[i].VirtualAddress - section[i].PointerToRawData; + return -1; +} + void * putmem (PIMAGE_THUNK_DATA pi, const void *hookfn) { @@ -152,7 +164,7 @@ makename (const char *name, char *&buf, int& i, int inc) void * hook_or_detect_cygwin (const char *name, const void *fn) { - HMODULE hm = GetModuleHandle (NULL); + HMODULE hm = fn ? GetModuleHandle (NULL) : (HMODULE) name; PIMAGE_NT_HEADERS pExeNTHdr = PEHeaderFromHModule (hm); if (!pExeNTHdr) @@ -163,18 +175,22 @@ hook_or_detect_cygwin (const char *name, const void *fn) if (!importRVA) return false; + long delta = fn ? 0 : rvadelta (pExeNTHdr, importRVA); + if (delta < 0) + return false; + // Convert imports RVA to a usable pointer - PIMAGE_IMPORT_DESCRIPTOR pdfirst = rva (PIMAGE_IMPORT_DESCRIPTOR, hm, importRVA); + PIMAGE_IMPORT_DESCRIPTOR pdfirst = rva (PIMAGE_IMPORT_DESCRIPTOR, hm, importRVA - delta); function_hook fh; fh.origfn = NULL; fh.hookfn = fn; - char *buf = (char *) alloca (strlen (name) + strlen ("64") + sizeof ("_")); + char *buf = fn ? NULL : (char *) alloca (strlen (name) + strlen ("64") + sizeof ("_")); int i; // Iterate through each import descriptor, and redirect if appropriate for (PIMAGE_IMPORT_DESCRIPTOR pd = pdfirst; pd->FirstThunk; pd++) { - if (!strcasematch (rva (PSTR, hm, pd->Name), "cygwin1.dll")) + if (!strcasematch (rva (PSTR, hm, pd->Name - delta), "cygwin1.dll")) continue; if (!fn) return (void *) "found it"; // just checking if executable used cygwin1.dll |