ms/uplink.c

   1 #if (defined(_WIN64) || defined(_WIN32_WCE)) && !defined(UNICODE)
   2 #define UNICODE
   3 #endif
   4 #if defined(UNICODE) && !defined(_UNICODE)
   5 #define _UNICODE
   6 #endif
   7 #if defined(_UNICODE) && !defined(UNICODE)
   8 #define UNICODE
   9 #endif
  10
  11 #include <windows.h>
  12 #include <tchar.h>
  13 #include <stdio.h>
  14 #include "uplink.h"
  15 void OPENSSL_showfatal(const char *,...);
  16
  17 static TCHAR msg[128];
  18
  19 static void unimplemented (void)
  20 {   OPENSSL_showfatal (sizeof(TCHAR)==sizeof(char)?"%s\n":"%S\n",msg);
  21     ExitProcess (1);
  22 }
  23
  24 void OPENSSL_Uplink (volatile void **table, int index)
  25 { static HMODULE volatile apphandle=NULL;
  26   static void ** volatile applinktable=NULL;
  27   int len;
  28   void (*func)(void)=unimplemented;
  29   HANDLE h;
  30   void **p;
  31
  32     /* Note that the below code is not MT-safe in respect to msg
  33      * buffer, but what's the worst thing that can happen? Error
  34      * message might be misleading or corrupted. As error condition
  35      * is fatal and should never be risen, I accept the risk... */
  36     /* One can argue that I should have used InterlockedExchangePointer
  37      * or something to update static variables and table[]. Well,
  38      * store instructions are as atomic as they can get and assigned
  39      * values are effectively constant... So that volatile qualifier
  40      * should be sufficient [it prohibits compiler to reorder memory
  41      * access instructions]. */
  42     do {
  43         len = _stprintf (msg,_T("OPENSSL_Uplink(%p,%02X): "),table,index);
  44         _tcscpy (msg+len,_T("unimplemented function"));
  45
  46         if ((h=apphandle)==NULL)
  47         {   if  ((h=GetModuleHandle(NULL))==NULL)
  48             {   apphandle=(HMODULE)-1;
  49                 _tcscpy (msg+len,_T("no host application"));
  50                 break;
  51             }
  52             apphandle = h;
  53         }
  54         if ((h=apphandle)==(HMODULE)-1) /* revalidate */
  55             break;
  56
  57         if (applinktable==NULL)
  58         { void**(*applink)();
  59
  60             applink=(void**(*)())GetProcAddress(h,"OPENSSL_Applink");
  61             if (applink==NULL)
  62             {   apphandle=(HMODULE)-1;
  63                 _tcscpy (msg+len,_T("no OPENSSL_Applink"));
  64                 break;
  65             }
  66             p = (*applink)();
  67             if (p==NULL)
  68             {   apphandle=(HMODULE)-1;
  69                 _tcscpy (msg+len,_T("no ApplinkTable"));
  70                 break;
  71             }
  72             applinktable = p;
  73         }
  74         else
  75             p = applinktable;
  76
  77         if (index > (int)p[0])
  78             break;
  79
  80         if (p[index]) func = p[index];
  81     } while (0);
  82
  83     table[index] = func;
  84 }
  85
  86 #if defined(_MSC_VER) && defined(_M_IX86) && !defined(OPENSSL_NO_INLINE_ASM)
  87 #define LAZY(i)         \
  88 __declspec(naked) static void lazy##i (void) {  \
  89         _asm    push i                          \
  90         _asm    push OFFSET OPENSSL_UplinkTable \
  91         _asm    call OPENSSL_Uplink             \
  92         _asm    add  esp,8                      \
  93         _asm    jmp  OPENSSL_UplinkTable+4*i    }
  94
  95 #if APPLINK_MAX>25
  96 #error "Add more stubs..."
  97 #endif
  98 /* make some in advance... */
  99 LAZY(1)  LAZY(2)  LAZY(3)  LAZY(4)  LAZY(5)
 100 LAZY(6)  LAZY(7)  LAZY(8)  LAZY(9)  LAZY(10)
 101 LAZY(11) LAZY(12) LAZY(13) LAZY(14) LAZY(15)
 102 LAZY(16) LAZY(17) LAZY(18) LAZY(19) LAZY(20)
 103 LAZY(21) LAZY(22) LAZY(23) LAZY(24) LAZY(25)
 104 void *OPENSSL_UplinkTable[] = {
 105         (void *)APPLINK_MAX,
 106         lazy1, lazy2, lazy3, lazy4, lazy5,
 107         lazy6, lazy7, lazy8, lazy9, lazy10,
 108         lazy11,lazy12,lazy13,lazy14,lazy15,
 109         lazy16,lazy17,lazy18,lazy19,lazy20,
 110         lazy21,lazy22,lazy23,lazy24,lazy25,
 111 };
 112 #endif
 113
 114 #ifdef SELFTEST
 115 main() {  UP_fprintf(UP_stdout,"hello, world!\n"); }
 116 #endif