diff options
Diffstat (limited to 'winsup/cygwin/pseudo-reloc.cc')
-rw-r--r-- | winsup/cygwin/pseudo-reloc.cc | 379 |
1 files changed, 0 insertions, 379 deletions
diff --git a/winsup/cygwin/pseudo-reloc.cc b/winsup/cygwin/pseudo-reloc.cc deleted file mode 100644 index df91e5889..000000000 --- a/winsup/cygwin/pseudo-reloc.cc +++ /dev/null @@ -1,379 +0,0 @@ -/* pseudo-reloc.cc - - Contributed by Egor Duda <deo@logos-m.ru> - Modified by addition of runtime_pseudo_reloc version 2 - by Kai Tietz <kai.tietz@onevision.com> - - THIS SOFTWARE IS NOT COPYRIGHTED - - This source code is offered for use in the public domain. You may - use, modify or distribute it freely. - - This code is distributed in the hope that it will be useful but - WITHOUT ANY WARRANTY. ALL WARRENTIES, EXPRESS OR IMPLIED ARE HEREBY - DISCLAMED. This includes but is not limited to warrenties of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. -*/ - -#ifndef __CYGWIN__ -# include "windows.h" -# define NO_COPY -#else -# include "winsup.h" -# include <sys/cygwin.h> -/* custom status code: */ -# define STATUS_ILLEGAL_DLL_PSEUDO_RELOCATION ((NTSTATUS) 0xe0000269) -#endif - -#include <stdio.h> -#include <stdlib.h> -#include <stdarg.h> -#include <memory.h> - -#ifdef __GNUC__ -#define ATTRIBUTE_NORETURN __attribute__ ((noreturn)) -#else -#define ATTRIBUTE_NORETURN -#endif - -#ifndef __MINGW_LSYMBOL -#define __MINGW_LSYMBOL(sym) sym -#endif - -extern char __RUNTIME_PSEUDO_RELOC_LIST__; -extern char __RUNTIME_PSEUDO_RELOC_LIST_END__; -extern char __MINGW_LSYMBOL(_image_base__); - -/* v1 relocation is basically: - * *(base + .target) += .addend - * where (base + .target) is always assumed to point - * to a DWORD (4 bytes). - */ -typedef struct { - DWORD addend; - DWORD target; -} runtime_pseudo_reloc_item_v1; - -/* v2 relocation is more complex. In effect, it is - * *(base + .target) += *(base + .sym) - (base + .sym) - * with care taken in both reading, sign extension, and writing - * because .flags may indicate that (base + .target) may point - * to a BYTE, WORD, DWORD, or QWORD (w64). - */ -typedef struct { - DWORD sym; - DWORD target; - DWORD flags; -} runtime_pseudo_reloc_item_v2; - -typedef struct { - DWORD magic1; - DWORD magic2; - DWORD version; -} runtime_pseudo_reloc_v2; - -static void ATTRIBUTE_NORETURN -__report_error (const char *msg, ...) -{ -#ifdef __CYGWIN__ - /* This function is used to print short error messages - * to stderr, which may occur during DLL initialization - * while fixing up 'pseudo' relocations. This early, we - * may not be able to use cygwin stdio functions, so we - * use the win32 WriteFile api. This should work with both - * normal win32 console IO handles, redirected ones, and - * cygwin ptys. - */ - char buf[128]; - WCHAR module[MAX_PATH]; - char * posix_module = NULL; - static const char UNKNOWN_MODULE[] = "<unknown module>: "; - static const char CYGWIN_FAILURE_MSG[] = "Cygwin runtime failure: "; - HANDLE errh = GetStdHandle (STD_ERROR_HANDLE); - ssize_t modulelen = GetModuleFileNameW (NULL, module, sizeof (module)); - va_list args; - - /* FIXME: cleanup further to avoid old use of cygwin_internal */ - if (errh == INVALID_HANDLE_VALUE) - cygwin_internal (CW_EXIT_PROCESS, STATUS_ILLEGAL_DLL_PSEUDO_RELOCATION, 1); - - if (modulelen > 0) - posix_module = (char *) cygwin_create_path (CCP_WIN_W_TO_POSIX, module); - - va_start (args, msg); - vsnprintf (buf, sizeof (buf), msg, args); - va_end (args); - buf[sizeof (buf) - 1] = '\0'; /* paranoia */ - - small_printf ("%s%s: %s\n", CYGWIN_FAILURE_MSG, posix_module ?: UNKNOWN_MODULE, buf); - if (posix_module) - free (posix_module); - - cygwin_internal (CW_EXIT_PROCESS, STATUS_ILLEGAL_DLL_PSEUDO_RELOCATION, 1); - /* not reached, but silences noreturn warning */ - abort (); -#else - va_list argp; - va_start (argp, msg); -# ifdef __MINGW64_VERSION_MAJOR - fprintf (stderr, "Mingw-w64 runtime failure:\n"); -# else - fprintf (stderr, "Mingw runtime failure:\n"); -# endif - vfprintf (stderr, msg, argp); - va_end (argp); - abort (); -#endif -} - -/* - * This function automatically sets addr as PAGE_EXECUTE_READWRITE - * by deciding whether VirtualQuery for the addr is actually needed. - * And it assumes that it is called in LdrpCallInitRoutine. - * Hence not thread safe. - */ -static void -auto_protect_for (void* addr) -{ - static MEMORY_BASIC_INFORMATION mbi; - static bool state = false; - static DWORD oldprot; - - if (!addr) - { - /* Restore original protection. */ - if (!(mbi.Protect & (PAGE_EXECUTE_READWRITE | PAGE_READWRITE))) - VirtualProtect (mbi.BaseAddress, mbi.RegionSize, oldprot, &oldprot); - state = false; - return; - } - if (state) - { - /* We have valid region information. Are we still within this region? - If so, just leave. */ - void *ptr = ((void*) ((ptrdiff_t) mbi.BaseAddress + mbi.RegionSize)); - if (addr >= mbi.BaseAddress && addr < ptr) - return; - /* Otherwise, restore original protection and fall through to querying - and potentially changing next region. */ - if (!(mbi.Protect & (PAGE_EXECUTE_READWRITE | PAGE_READWRITE))) - VirtualProtect (mbi.BaseAddress, mbi.RegionSize, oldprot, &oldprot); - } - else - state = true; - /* Query region and temporarily allow write access to read-only protected - memory. */ - VirtualQuery (addr, &mbi, sizeof mbi); - if (!(mbi.Protect & (PAGE_EXECUTE_READWRITE | PAGE_READWRITE))) - VirtualProtect (mbi.BaseAddress, mbi.RegionSize, - PAGE_EXECUTE_READWRITE, &oldprot); -} - -/* This function temporarily marks the page containing addr - * writable, before copying len bytes from *src to *addr, and - * then restores the original protection settings to the page. - * - * Using this function eliminates the requirement with older - * pseudo-reloc implementations, that sections containing - * pseudo-relocs (such as .text and .rdata) be permanently - * marked writable. This older behavior sabotaged any memory - * savings achieved by shared libraries on win32 -- and was - * slower, too. However, on cygwin as of binutils 2.20 the - * .text section is still marked writable, and the .rdata section - * is folded into the (writable) .data when --enable-auto-import. - */ -static void -__write_memory (void *addr, const void *src, size_t len) -{ - if (!len) - return; - /* Fix page protection for writing. */ - auto_protect_for (addr); - /* write the data. */ - memcpy (addr, src, len); -} - -#define RP_VERSION_V1 0 -#define RP_VERSION_V2 1 - -static void -do_pseudo_reloc (void * start, void * end, void * base) -{ - ptrdiff_t addr_imp, reldata; - ptrdiff_t reloc_target = (ptrdiff_t) ((char *)end - (char*)start); - runtime_pseudo_reloc_v2 *v2_hdr = (runtime_pseudo_reloc_v2 *) start; - runtime_pseudo_reloc_item_v2 *r; - - /* A valid relocation list will contain at least one entry, and - * one v1 data structure (the smallest one) requires two DWORDs. - * So, if the relocation list is smaller than 8 bytes, bail. - */ - if (reloc_target < 8) - return; - - /* Check if this is the old pseudo relocation version. */ - /* There are two kinds of v1 relocation lists: - * 1) With a (v2-style) version header. In this case, the - * first entry in the list is a 3-DWORD structure, with - * value: - * { 0, 0, RP_VERSION_V1 } - * In this case, we skip to the next entry in the list, - * knowing that all elements after the head item can - * be cast to runtime_pseudo_reloc_item_v1. - * 2) Without a (v2-style) version header. In this case, the - * first element in the list IS an actual v1 relocation - * record, which is two DWORDs. Because there will never - * be a case where a v1 relocation record has both - * addend == 0 and target == 0, this case will not be - * confused with the prior one. - * All current binutils, when generating a v1 relocation list, - * use the second (e.g. original) form -- that is, without the - * v2-style version header. - */ - if (reloc_target >= 12 - && v2_hdr->magic1 == 0 && v2_hdr->magic2 == 0 - && v2_hdr->version == RP_VERSION_V1) - { - /* We have a list header item indicating that the rest - * of the list contains v1 entries. Move the pointer to - * the first true v1 relocation record. By definition, - * that v1 element will not have both addend == 0 and - * target == 0 (and thus, when interpreted as a - * runtime_pseudo_reloc_v2, it will not have both - * magic1 == 0 and magic2 == 0). - */ - v2_hdr++; - } - - if (v2_hdr->magic1 != 0 || v2_hdr->magic2 != 0) - { - /************************* - * Handle v1 relocations * - *************************/ - runtime_pseudo_reloc_item_v1 * o; - for (o = (runtime_pseudo_reloc_item_v1 *) v2_hdr; - o < (runtime_pseudo_reloc_item_v1 *)end; - o++) - { - DWORD newval; - reloc_target = (ptrdiff_t) base + o->target; - newval = (*((DWORD*) reloc_target)) + o->addend; - __write_memory ((void *) reloc_target, &newval, sizeof (DWORD)); - } - /* Restore original protection. */ - auto_protect_for (NULL); - return; - } - - /* If we got this far, then we have relocations of version 2 or newer */ - - /* Check if this is a known version. */ - if (v2_hdr->version != RP_VERSION_V2) - { - __report_error (" Unknown pseudo relocation protocol version %d.\n", - (int) v2_hdr->version); - return; - } - - /************************* - * Handle v2 relocations * - *************************/ - - /* Walk over header. */ - r = (runtime_pseudo_reloc_item_v2 *) &v2_hdr[1]; - - for (; r < (runtime_pseudo_reloc_item_v2 *) end; r++) - { - /* location where new address will be written */ - reloc_target = (ptrdiff_t) base + r->target; - - /* get sym pointer. It points either to the iat entry - * of the referenced element, or to the stub function. - */ - addr_imp = (ptrdiff_t) base + r->sym; - addr_imp = *((ptrdiff_t *) addr_imp); - - /* read existing relocation value from image, casting to the - * bitsize indicated by the 8 LSBs of flags. If the value is - * negative, manually sign-extend to ptrdiff_t width. Raise an - * error if the bitsize indicated by the 8 LSBs of flags is not - * supported. - */ - switch ((r->flags & 0xff)) - { - case 8: - reldata = (ptrdiff_t) (*((unsigned char *)reloc_target)); - if ((reldata & 0x80) != 0) - reldata |= ~((ptrdiff_t) 0xff); - break; - case 16: - reldata = (ptrdiff_t) (*((unsigned short *)reloc_target)); - if ((reldata & 0x8000) != 0) - reldata |= ~((ptrdiff_t) 0xffff); - break; - case 32: - reldata = (ptrdiff_t) (*((unsigned int *)reloc_target)); -#ifdef _WIN64 - if ((reldata & 0x80000000) != 0) - reldata |= ~((ptrdiff_t) 0xffffffff); -#endif - break; -#ifdef _WIN64 - case 64: - reldata = (ptrdiff_t) (*((unsigned long long *)reloc_target)); - break; -#endif - default: - reldata=0; - __report_error (" Unknown pseudo relocation bit size %d.\n", - (int) (r->flags & 0xff)); - break; - } - - /* Adjust the relocation value */ - reldata -= ((ptrdiff_t) base + r->sym); - reldata += addr_imp; - - /* Write the new relocation value back to *reloc_target */ - switch ((r->flags & 0xff)) - { - case 8: - __write_memory ((void *) reloc_target, &reldata, 1); - break; - case 16: - __write_memory ((void *) reloc_target, &reldata, 2); - break; - case 32: - __write_memory ((void *) reloc_target, &reldata, 4); - break; -#ifdef _WIN64 - case 64: - __write_memory ((void *) reloc_target, &reldata, 8); - break; -#endif - } - } - /* Restore original protection. */ - auto_protect_for (NULL); -} - -#ifdef __CYGWIN__ -extern "C" void -_pei386_runtime_relocator (per_process *u) -{ - if (u && CYGWIN_VERSION_USE_PSEUDO_RELOC_IN_DLL (u)) - do_pseudo_reloc (u->pseudo_reloc_start, u->pseudo_reloc_end, u->image_base); -} -#else -extern "C" void -_pei386_runtime_relocator (void) -{ - static NO_COPY int was_init = 0; - if (was_init) - return; - ++was_init; - do_pseudo_reloc (&__RUNTIME_PSEUDO_RELOC_LIST__, - &__RUNTIME_PSEUDO_RELOC_LIST_END__, - &__MINGW_LSYMBOL(_image_base__)); -} -#endif |