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-rw-r--r--winsup/cygwin/hookapi.cc304
1 files changed, 0 insertions, 304 deletions
diff --git a/winsup/cygwin/hookapi.cc b/winsup/cygwin/hookapi.cc
deleted file mode 100644
index 7a13ee0..0000000
--- a/winsup/cygwin/hookapi.cc
+++ /dev/null
@@ -1,304 +0,0 @@
-/* hookapi.cc
-
- Copyright 2005, 2006, 2007, 2008 Red Hat, Inc.
-
-This file is part of Cygwin.
-
-This software is a copyrighted work licensed under the terms of the
-Cygwin license. Please consult the file "CYGWIN_LICENSE" for
-details. */
-
-#include "winsup.h"
-#include <stdlib.h>
-#include "ntdll.h"
-#include "cygerrno.h"
-#include "security.h"
-#include "path.h"
-#include "fhandler.h"
-#include "dtable.h"
-#include "cygheap.h"
-
-#define rva(coerce, base, addr) (coerce) ((char *) (base) + (addr))
-#define rvacyg(coerce, addr) rva (coerce, cygwin_hmodule, addr)
-
-struct function_hook
-{
- const char *name; // Function name, e.g. "DirectDrawCreateEx".
- const void *hookfn; // Address of your function.
- void *origfn; // Stored by HookAPICalls, the address of the original function.
-};
-
-/* Given an HMODULE, returns a pointer to the PE header */
-static PIMAGE_NT_HEADERS
-PEHeaderFromHModule (HMODULE hModule)
-{
- PIMAGE_NT_HEADERS pNTHeader;
-
- if (PIMAGE_DOS_HEADER(hModule) ->e_magic != IMAGE_DOS_SIGNATURE)
- pNTHeader = NULL;
- else
- {
- pNTHeader = PIMAGE_NT_HEADERS (PBYTE (hModule)
- + PIMAGE_DOS_HEADER (hModule) ->e_lfanew);
- if (pNTHeader->Signature != IMAGE_NT_SIGNATURE)
- pNTHeader = NULL;
- }
-
- return pNTHeader;
-}
-
-static long
-rvadelta (PIMAGE_NT_HEADERS pnt, DWORD 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 (ascii_strncasematch ((char *) section[i].Name, ".idata", IMAGE_SIZEOF_SHORT_NAME))
- return section[i].VirtualAddress - section[i].PointerToRawData;
- return -1;
-}
-
-static void *
-putmem (PIMAGE_THUNK_DATA pi, const void *hookfn)
-{
- DWORD ofl;
- if (!VirtualProtect (pi, sizeof (PVOID), PAGE_READWRITE, &ofl) )
- return NULL;
-
- void *origfn = (void *) pi->u1.Function;
- pi->u1.Function = (DWORD) hookfn;
-
- VirtualProtect (pi, sizeof (PVOID), ofl, &ofl);
- return origfn;
-}
-
-/* Builds stubs for and redirects the IAT for one DLL (pImportDesc) */
-
-static bool
-RedirectIAT (function_hook& fh, PIMAGE_IMPORT_DESCRIPTOR pImportDesc,
- HMODULE hm)
-{
- // If no import names table, we can't redirect this, so bail
- if (pImportDesc->OriginalFirstThunk == 0)
- return false;
-
- /* import address table */
- PIMAGE_THUNK_DATA pt = rva (PIMAGE_THUNK_DATA, hm, pImportDesc->FirstThunk);
- /* import names table */
- PIMAGE_THUNK_DATA pn = rva (PIMAGE_THUNK_DATA, hm, pImportDesc->OriginalFirstThunk);
-
- /* Scan through the IAT, completing the stubs and redirecting the IAT
- entries to point to the stubs. */
- for (PIMAGE_THUNK_DATA pi = pt; pn->u1.Ordinal; pi++, pn++)
- {
- if (IMAGE_SNAP_BY_ORDINAL (pn->u1.Ordinal) )
- continue;
-
- /* import by name */
- PIMAGE_IMPORT_BY_NAME pimp = rva (PIMAGE_IMPORT_BY_NAME, hm, pn->u1.AddressOfData);
-
- if (strcmp (fh.name, (char *) pimp->Name) == 0)
- {
- fh.origfn = putmem (pi, fh.hookfn);
- if (!fh.origfn)
- return false;
- hook_chain *hc;
- for (hc = &cygheap->hooks; hc->next; hc = hc->next)
- continue;
- hc->next = (hook_chain *) cmalloc_abort (HEAP_1_HOOK, sizeof (hook_chain));
- hc->next->loc = (void **) pi;
- hc->next->func = fh.hookfn;
- hc->next->next = NULL;
- break;
- }
- }
-
- return true;
-}
-
-static void
-get_export (function_hook& fh)
-{
- PIMAGE_DOS_HEADER pdh = (PIMAGE_DOS_HEADER) cygwin_hmodule;
- if (pdh->e_magic != IMAGE_DOS_SIGNATURE)
- return;
- PIMAGE_NT_HEADERS pnt = (PIMAGE_NT_HEADERS) ((char *) pdh + pdh->e_lfanew);
- if (pnt->Signature != IMAGE_NT_SIGNATURE || pnt->FileHeader.SizeOfOptionalHeader == 0)
- return;
- PIMAGE_EXPORT_DIRECTORY pexp =
- rvacyg (PIMAGE_EXPORT_DIRECTORY,
- pnt->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT].VirtualAddress);
- if (!pexp)
- return;
-
- PDWORD pfuncs = rvacyg (PDWORD, pexp->AddressOfFunctions);
- PDWORD pnames = rvacyg (PDWORD, pexp->AddressOfNames);
- for (DWORD i = 0; i < pexp->NumberOfNames; i++)
- if (strcmp (fh.name, rvacyg (char *, pnames[i])) == 0)
- {
- fh.origfn = rvacyg (void *, pfuncs[i]);
- break;
- }
-}
-
-static const char *
-makename (const char *name, char *&buf, int& i, int inc)
-{
- i += inc;
- static const char *testers[] = {"NOTUSED", "64", "32"};
- if (i < 0 || i >= (int) (sizeof (testers) / sizeof (testers[0])))
- return NULL;
- if (i)
- {
- __small_sprintf (buf, "_%s%s", name, testers[i]);
- name = buf;
- }
- return name;
-}
-
-/* Find first missing dll in a given executable.
- FIXME: This is not foolproof since it doesn't look for dlls in the
- same directory as the given executable, like Windows. Instead it
- searches for dlls in the context of the current executable. */
-const char *
-find_first_notloaded_dll (path_conv& pc)
-{
- const char *res = "?";
- HANDLE hc = NULL;
- HMODULE hm = NULL;
- OBJECT_ATTRIBUTES attr;
- IO_STATUS_BLOCK io;
- HANDLE h;
- NTSTATUS status;
-
- status = NtOpenFile (&h, SYNCHRONIZE | GENERIC_READ,
- pc.get_object_attr (attr, sec_none_nih),
- &io, FILE_SHARE_READ | FILE_SHARE_WRITE,
- FILE_SYNCHRONOUS_IO_NONALERT
- | FILE_OPEN_FOR_BACKUP_INTENT
- | FILE_NON_DIRECTORY_FILE);
- if (!NT_SUCCESS (status))
- goto out;
-
- hc = CreateFileMapping (h, &sec_none_nih, PAGE_READONLY, 0, 0, NULL);
- NtClose (h);
- if (!hc)
- goto out;
- hm = (HMODULE) MapViewOfFile(hc, FILE_MAP_READ, 0, 0, 0);
- CloseHandle (hc);
-
- PIMAGE_NT_HEADERS pExeNTHdr;
- pExeNTHdr = PEHeaderFromHModule (hm);
-
- if (pExeNTHdr)
- {
- DWORD importRVA;
- importRVA = pExeNTHdr->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT].VirtualAddress;
- if (importRVA)
- {
- long delta = rvadelta (pExeNTHdr, importRVA);
-
- // Convert imports RVA to a usable pointer
- PIMAGE_IMPORT_DESCRIPTOR pdfirst;
- pdfirst = rva (PIMAGE_IMPORT_DESCRIPTOR, hm, importRVA - delta);
-
- // Iterate through each import descriptor, and redirect if appropriate
- for (PIMAGE_IMPORT_DESCRIPTOR pd = pdfirst; pd->FirstThunk; pd++)
- {
- const char *lib = rva (PSTR, hm, pd->Name - delta);
- if (!LoadLibraryEx (lib, NULL, DONT_RESOLVE_DLL_REFERENCES
- | LOAD_LIBRARY_AS_DATAFILE))
- {
- static char buf[NT_MAX_PATH];
- res = strcpy (buf, lib);
- }
- }
- }
- }
-
-out:
- if (hm)
- UnmapViewOfFile (hm);
-
- return res;
-}
-
-// Top level routine to find the EXE's imports and redirect them
-void *
-hook_or_detect_cygwin (const char *name, const void *fn, WORD& subsys)
-{
- HMODULE hm = fn ? GetModuleHandle (NULL) : (HMODULE) name;
- PIMAGE_NT_HEADERS pExeNTHdr = PEHeaderFromHModule (hm);
-
- if (!pExeNTHdr)
- return false;
-
- subsys = pExeNTHdr->OptionalHeader.Subsystem;
-
- DWORD importRVA = pExeNTHdr->OptionalHeader.DataDirectory
- [IMAGE_DIRECTORY_ENTRY_IMPORT].VirtualAddress;
- 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 - delta);
-
- function_hook fh;
- fh.origfn = NULL;
- fh.hookfn = fn;
- char *buf = (char *) alloca (strlen (name) + sizeof ("_64"));
- int i;
- // Iterate through each import descriptor, and redirect if appropriate
- for (PIMAGE_IMPORT_DESCRIPTOR pd = pdfirst; pd->FirstThunk; pd++)
- {
- if (!ascii_strcasematch (rva (PSTR, hm, pd->Name - delta), "cygwin1.dll"))
- continue;
- if (!fn)
- return (void *) "found it"; // just checking if executable used cygwin1.dll
- i = -1;
- while (!fh.origfn && (fh.name = makename (name, buf, i, 1)))
- RedirectIAT (fh, pd, hm);
- if (fh.origfn)
- break;
- }
-
- while (!fh.origfn && (fh.name = makename (name, buf, i, -1)))
- get_export (fh);
-
- return fh.origfn;
-}
-
-void
-ld_preload ()
-{
- char *p = getenv ("LD_PRELOAD");
- if (!p)
- return;
- char *s = (char *) alloca (strlen (p) + 1);
- strcpy (s, p);
- char *here = NULL;
- for (p = strtok_r (s, ":\t\n", &here); p; p = strtok_r (NULL, ":\t\n", &here))
- {
- path_conv lib (p);
- WCHAR libname[lib.get_wide_win32_path_len () + 1];
- if (!LoadLibraryW (lib.get_wide_win32_path (libname)))
- {
- __seterrno ();
- api_fatal ("error while loading shared libraries: %s: "
- "cannot open shared object file: %s", p,
- strerror (get_errno ()));
- }
- }
-}
-
-void
-fixup_hooks_after_fork ()
-{
- for (hook_chain *hc = &cygheap->hooks; (hc = hc->next); )
- putmem ((PIMAGE_THUNK_DATA) hc->loc, hc->func);
-}
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