src/libcaptive/ldr/loader.c

   1 /* $Id$
   2  * reactos ldr/ (loader) emulation of libcaptive
   3  * Copyright (C) 2002 Jan Kratochvil <project-captive@jankratochvil.net>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; exactly version 2 of June 1991 is required
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  17  */
  18
  19
  20 #include "config.h"
  21
  22 #include "captive/ldr.h"        /* self */
  23 #include "captive/ldr_exports.h"        /* self */
  24 #include "reactos/internal/ldr.h"       /* self */
  25 #include "captive/unicode.h"
  26 #include "captive/rtl-file.h"
  27 #include <glib/gtypes.h>
  28 #include <glib/gmessages.h>
  29 #include <glib/gmem.h>
  30 #include "reactos/napi/types.h"
  31 #include "reactos/internal/kd.h"        /* for KDB_LOADDRIVER_HOOK */
  32 #include <fcntl.h>
  33 #include <sys/mman.h>   /* for PROT_READ, MAP_SHARED */
  34 #include "captive/macros.h"
  35 #include <stdarg.h>
  36 #include "reactos/ntos/rtl.h"   /* for InsertTailList() */
  37 #include "reactos/internal/debug.h"     /* for assert() */
  38 #include <glib/gutils.h>        /* for g_path_get_basename() */
  39 #include <gmodule.h>
  40 #include "captive/options-module.h"
  41
  42
  43 /* map: ExportAddress -> (struct captive_ModuleList_patchpoint *) */
  44 static GHashTable *captive_ModuleList_patchpoint_hash;
  45
  46 /* initialize 'captive_ModuleList_patchpoint_hash' */
  47 static void captive_ModuleList_patchpoint_hash_init(void)
  48 {
  49         if (captive_ModuleList_patchpoint_hash)
  50                 return;
  51         captive_ModuleList_patchpoint_hash=g_hash_table_new(g_direct_hash,g_direct_equal);
  52 }
  53
  54
  55 /* map: ExportAddress -> (CHAR *)funcname */
  56 static GHashTable *captive_ModuleList_function_disable_hash;
  57
  58 /* initialize 'captive_ModuleList_function_disable_hash' */
  59 static void captive_ModuleList_function_disable_hash_init(void)
  60 {
  61         if (captive_ModuleList_function_disable_hash)
  62                 return;
  63         captive_ModuleList_function_disable_hash=g_hash_table_new(g_direct_hash,g_direct_equal);
  64 }
  65
  66
  67 /* reactos/ntoskrnl/ldr/loader.c file-scope global declaration: */
  68 NTSTATUS LdrProcessModule(PVOID ModuleLoadBase,PUNICODE_STRING ModuleName,PMODULE_OBJECT *ModuleObject);
  69 PVOID LdrGetExportAddress(PMODULE_OBJECT ModuleObject,char *Name,unsigned short Hint);
  70
  71
  72 /* 'ntoskrnl/ldr/loader.c' file-scoped declaration: */
  73 VOID LdrpBuildModuleBaseName(PUNICODE_STRING BaseName,PUNICODE_STRING FullName);
  74
  75
  76 static MODULE_OBJECT *captive_LdrLoadModule_gmodule(const gchar *Filename_utf8,const gchar *Filename_bslash_utf8)
  77 {
  78 MODULE_OBJECT *r;
  79 GModule *gmodule;
  80 MODULE_TEXT_SECTION *ModuleTextSection;
  81 gboolean errbool;
  82
  83         g_return_val_if_fail(Filename_utf8!=NULL,NULL);
  84         g_return_val_if_fail(Filename_bslash_utf8!=NULL,NULL);
  85         g_return_val_if_fail(TRUE==g_module_supported(),NULL);
  86
  87         gmodule=g_module_open(Filename_utf8,
  88                         0);     /* Flags; !LAZY */
  89         if (!gmodule)
  90                 g_message(g_module_error());
  91         g_assert(gmodule!=NULL);
  92
  93         captive_new0(r);
  94
  95         errbool=g_module_symbol(gmodule,"DriverEntry",&r->EntryPoint);
  96         g_assert(errbool==TRUE);
  97
  98         r->Base=(PVOID)gmodule;
  99         r->Flags=MODULE_FLAG_COFF;      /* some weird value - reactos uses MODULE_FLAG_PE */
 100
 101         RtlCreateUnicodeString(&r->FullName,captive_utf8_to_UnicodeString_alloca(Filename_bslash_utf8)->Buffer);
 102   LdrpBuildModuleBaseName(&r->BaseName,&r->FullName);
 103
 104         /* r->Length=0; */
 105
 106   /* Insert module */
 107         InsertTailList(&ModuleListHead,&r->ListEntry);
 108
 109         captive_new0(ModuleTextSection);
 110         /* ModuleTextSection->Base=0; */
 111         /* ModuleTextSection->Length=0; */
 112         ModuleTextSection->Name=g_memdup(r->BaseName.Buffer,
 113                         (captive_ucs2_strlen(r->BaseName.Buffer)+1)*sizeof(captive_ucs2));
 114         /* ModuleTextSection->OptionalHeader=NULL; */
 115         InsertTailList(&ModuleTextListHead,&ModuleTextSection->ListEntry);
 116         r->TextSection=ModuleTextSection;
 117
 118         return r;
 119 }
 120
 121
 122 /**
 123  * captive_LdrLoadModule:
 124  * @Filename: Filename of module to load based on host OS disk.
 125  * Loading of already loaded module is forbidden.
 126  * @ModuleObject: Returns initialized module object.
 127  *
 128  * Load and initialize module to reactos using host OS functions.
 129  *
 130  * Returns: STATUS_SUCCESS if the module was loaded successfuly during the call.
 131  */
 132 NTSTATUS captive_LdrLoadModule(struct captive_options_module *options_module,PMODULE_OBJECT *ModuleObjectp)
 133 {
 134 PMODULE_OBJECT Module;
 135 NTSTATUS err;
 136 gchar *Filename_utf8=options_module->pathname_utf8;
 137 gchar *Filename_bslash_utf8,*s;
 138 UNICODE_STRING *Filename_bslash;
 139
 140         *ModuleObjectp=NULL;
 141
 142         /* Filename=~s#/#\\#g -> Filename_bslash to satisfy basename-derivations by reactos. */
 143         Filename_bslash_utf8=(/* de-const as we do not change the length */ gchar *)captive_strdup_alloca(Filename_utf8);
 144         for (s=Filename_bslash_utf8;(s=strchr(s,'/'));s++)
 145                 *s='\\';
 146         Filename_bslash=captive_utf8_to_UnicodeString_alloca(Filename_bslash_utf8);
 147
 148         switch (options_module->type) {
 149                 case CAPTIVE_OPTIONS_MODULE_TYPE_EMPTY: g_assert_not_reached();
 150
 151                 case CAPTIVE_OPTIONS_MODULE_TYPE_PE32:
 152                         g_log(G_LOG_DOMAIN,G_LOG_LEVEL_DEBUG,"%s: Loading module format: %s",G_STRLOC,"MZ/PE-32");
 153                         /* examine/relocate the module */
 154                         err=LdrProcessModule(options_module->u.pe32.base,Filename_bslash,&Module);
 155                         if (!NT_SUCCESS(err)) {
 156                                 g_error("LdrLoadModule(): LdrProcessModule()=0x%08lX",(gulong)err);
 157                                 goto err;
 158                                 }
 159                         break;
 160
 161                 case CAPTIVE_OPTIONS_MODULE_TYPE_GMODULE:
 162                         g_log(G_LOG_DOMAIN,G_LOG_LEVEL_DEBUG,"%s: Loading module format: %s",G_STRLOC,"native .so");
 163                         Module=captive_LdrLoadModule_gmodule(Filename_utf8,Filename_bslash_utf8);
 164                         g_assert(Module!=NULL);
 165                 }
 166
 167         /* we were successful */
 168         *ModuleObjectp=Module;
 169
 170         /* Hook for KDB on loading a driver. */
 171         KDB_LOADDRIVER_HOOK(Filename_bslash,Module);
 172
 173         return STATUS_SUCCESS;
 174
 175 err:
 176         g_return_val_if_reached(err);
 177 }
 178
 179
 180 NTSTATUS LdrLoadModule(PUNICODE_STRING Filename,PMODULE_OBJECT *ModuleObject)
 181 {
 182         return STATUS_OBJECT_NAME_NOT_FOUND;
 183 }
 184
 185
 186 /**
 187  * captive_LdrpLoadAndCallImage:
 188  * @ModuleObjectp: Returns PMODULE_OBJECT successfuly loaded.
 189  * @ModuleName: Filename of module to load based on host OS disk.
 190  * Loading of already loaded module is forbidden despite original
 191  * LdrpLoadAndCallImage().
 192  * @DriverEntry_DriverObject: argument #DriverObject of #PDRIVER_INITIALIZE call.
 193  * @DriverEntry_RegistryPath: argument #RegistryPath of #PDRIVER_INITIALIZE call.
 194  *
 195  * Corresponds to reactos LdrpLoadAndCallImage() but it also provides arguments
 196  * to pass to #PDRIVER_INITIALIZE call of module driver initialization.
 197  *
 198  * Returns: STATUS_SUCCESS if the driver module was loaded and initialized
 199  * successfuly during this call. Ignore returned @ModuleObjectp if function failed.
 200  */
 201 NTSTATUS captive_LdrpLoadAndCallImage(PMODULE_OBJECT *ModuleObjectp,struct captive_options_module *options_module,
 202                 PDRIVER_OBJECT DriverEntry_DriverObject,PUNICODE_STRING DriverEntry_RegistryPath)
 203 {
 204 PDRIVER_INITIALIZE DriverEntry;
 205 PMODULE_OBJECT ModuleObject_tmp;
 206 NTSTATUS err;
 207
 208 #if 0   /* TODO */
 209         /* check for duplicity */
 210         g_return_val_if_fail(LdrGetModuleObject(ModuleName)==NULL,STATUS_IMAGE_ALREADY_LOADED);
 211 #endif
 212
 213         /* provide our temporary storage if the caller doesn't want to know ModuleObject address */
 214         if (!ModuleObjectp)
 215                 ModuleObjectp=&ModuleObject_tmp;
 216
 217         /* load the module */
 218         err=captive_LdrLoadModule(options_module,ModuleObjectp);
 219         g_return_val_if_fail(NT_SUCCESS(err),err);
 220
 221         /* initialize the module */
 222         DriverEntry=(PDRIVER_INITIALIZE)(*ModuleObjectp)->EntryPoint;
 223         err=(*DriverEntry)(DriverEntry_DriverObject,DriverEntry_RegistryPath);
 224         if (!NT_SUCCESS(err))
 225                 goto err_LdrUnloadModule;
 226
 227         /* assumed STATUS_SUCCESS */
 228         return err;
 229
 230 err_LdrUnloadModule:
 231         /* errors ignored */
 232         LdrUnloadModule(*ModuleObjectp);
 233         *ModuleObjectp=NULL;
 234 /* err: */
 235         g_return_val_if_reached(err);
 236 }
 237
 238
 239 /**
 240  * captive_ModuleList_add_builtin:
 241  * @FullName_utf8: String to fill in #PMODULE_OBJECT->FullName.
 242  * @...: (const gchar *sym_name,void *sym_val) symbol list terminated by %NULL.
 243  *
 244  * Adds simulated built-in module to #ModuleListHead module list.
 245  * It can be used for the functionality of reactos/ntoskrnl/ldr/loader.c/LdrInitModuleManagement().
 246  * libcaptive does not support Ordinals - we just pretend liner (%0-based)
 247  * Ordinal numbers of the functions in given @... stdargs order.
 248  *
 249  * Returns: %TRUE if the module was successfuly added.
 250  */
 251 gboolean captive_ModuleList_add_builtin(const gchar *FullName_utf8,...)
 252 {
 253 MODULE_OBJECT *ModuleObject;
 254 BOOLEAN errbool;
 255 va_list ap;
 256 const gchar *sym_name;
 257 const void *sym_val;
 258 gchar *basename_utf8;
 259 IMAGE_DOS_HEADER *DosHeader;
 260 IMAGE_NT_HEADERS *NTHeaders;
 261 IMAGE_EXPORT_DIRECTORY *ExportDir;
 262 guint symi,symN;        /* index,number of passed stdarg sym_name/sym_val pairs */
 263 ptrdiff_t *NameList;    /* filled by sym_name; MODULEOBJECT_BASE_OFFSET_MINUS()ed */
 264 WORD *OrdinalList;      /* linear list - libcaptive doesn't support Ordinals */
 265 ptrdiff_t *FunctionList;        /* filled by sym_val; MODULEOBJECT_BASE_OFFSET_MINUS()ed */
 266
 267         g_return_val_if_fail(FullName_utf8!=NULL,FALSE);
 268
 269         captive_new0(ModuleObject);
 270         /* A lot of offsets in the structures are relative to ModuleObject->Base */
 271 #define MODULEOBJECT_BASE_OFFSET_MINUS(addr) ((ptrdiff_t)((char *)addr-(char *)ModuleObject->Base))
 272
 273         ModuleObject->Flags = MODULE_FLAG_PE;
 274
 275         /* fill ModuleObject->FullName
 276          * ModuleObject->FullName should be probably "\\SYSTEM32\\..." style but
 277          * we put there '/'-based UNIX filenames in libcaptive.
 278          */
 279         errbool=RtlCreateUnicodeString(&ModuleObject->FullName,captive_utf8_to_UnicodeString_alloca(FullName_utf8)->Buffer);
 280         if (!errbool) {
 281                 g_error("captive_ModuleList_add_builtin: RtlCreateUnicodeString()==FALSE");
 282                 goto err_g_free_ModuleObject;
 283                 }
 284
 285         /* fill ModuleObject->BaseName
 286          * reactos/ntoskrnl/ldr/loader.c/LdrpBuildModuleBaseName() does this one
 287          * but it is 'static' for that file and also it is stricly backslash based.
 288          * ModuleObject->FullName should be probably "\\SYSTEM32\\..." style but
 289          * we put there '/'-based UNIX filenames in libcaptive.
 290          */
 291         basename_utf8=g_path_get_basename(FullName_utf8);
 292         errbool=RtlCreateUnicodeString(&ModuleObject->BaseName,captive_utf8_to_UnicodeString_alloca(basename_utf8)->Buffer);
 293         g_free(basename_utf8);
 294         if (!errbool) {
 295                 g_error("captive_ModuleList_add_builtin: RtlCreateUnicodeString()==FALSE");
 296                 goto err_g_free_ModuleObject;
 297                 }
 298
 299         /* We must satisfy reactos/ntoskrnl/ldr/rtl.c/RtlImageDirectoryEntryToData(,,IMAGE_DIRECTORY_ENTRY_EXPORT)
 300          * prepare module headers
 301          */
 302         captive_new0(DosHeader);
 303         ModuleObject->Base=DosHeader;   /* link DosHeader to ModuleObject */
 304         DosHeader->e_magic=IMAGE_DOS_MAGIC;
 305         captive_new0(NTHeaders);
 306         DosHeader->e_lfanew=MODULEOBJECT_BASE_OFFSET_MINUS(NTHeaders);  /* link NTHeaders to DosHeader */
 307         NTHeaders->Signature=IMAGE_PE_MAGIC;
 308         NTHeaders->OptionalHeader.NumberOfRvaAndSizes=IMAGE_DIRECTORY_ENTRY_EXPORT+1;
 309         NTHeaders->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT].Size
 310                         =sizeof(*ExportDir);    /* in bytes; just prevent LdrPEFixupForward() invocation */
 311         captive_new0(ExportDir);
 312         NTHeaders->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT].VirtualAddress
 313                         =MODULEOBJECT_BASE_OFFSET_MINUS(ExportDir);     /* link ExportDir to NTHeaders */
 314         ExportDir->Base=0;      /* base Ordinal number; Ordinals are not supported by libcaptive */
 315
 316         /* count the number of symbols */
 317         va_start(ap,FullName_utf8);
 318         for (symN=0;captive_va_arg(sym_name,ap);symN++)
 319                 captive_va_arg(sym_val,ap);
 320         va_end(ap);
 321         ExportDir->NumberOfNames=symN;
 322         ExportDir->NumberOfFunctions=symN;
 323
 324         /* allocate and link the symbol tables */
 325         captive_newn(NameList,symN);
 326         ExportDir->AddressOfNames=(PDWORD *)MODULEOBJECT_BASE_OFFSET_MINUS(NameList);   /* link NameList to ExportDir */
 327         captive_newn(OrdinalList,symN);
 328         ExportDir->AddressOfNameOrdinals=(PWORD *)MODULEOBJECT_BASE_OFFSET_MINUS(OrdinalList);  /* link OrdinalList to ExportDir */
 329         captive_newn(FunctionList,symN);
 330         ExportDir->AddressOfFunctions=(PDWORD *)MODULEOBJECT_BASE_OFFSET_MINUS(FunctionList);   /* link FunctionList to ExportDir */
 331
 332         /* fill in symbol tables */
 333         va_start(ap,FullName_utf8);
 334         for (symi=0;symi<symN;symi++) {
 335                 captive_va_arg(sym_name,ap);
 336                 captive_va_arg(sym_val ,ap);
 337                 NameList[symi]=MODULEOBJECT_BASE_OFFSET_MINUS(sym_name);
 338                 OrdinalList[symi]=symi; /* Ordinals are not supported by libcaptive */
 339                 FunctionList[symi]=MODULEOBJECT_BASE_OFFSET_MINUS(sym_val);
 340                 }
 341         va_end(ap);
 342
 343         /* successful module info build */
 344         InsertTailList(&ModuleListHead,&ModuleObject->ListEntry);
 345         return TRUE;
 346
 347 err_g_free_ModuleObject:
 348         g_free(ModuleObject);
 349 /* err */
 350         g_return_val_if_reached(FALSE);
 351 }
 352
 353
 354 static gsize instruction_length(const guint8 *instr)
 355 {
 356         if ((instr[0] & 0xF8)==0x50)    /* push %regular-register */
 357                 return 1;
 358         if ((instr[0] & 0xF8)==0x58)    /* pop  %regular-register */
 359                 return 1;
 360         if ((instr[0] & 0xE7)==0x06)    /* push %segment-register */
 361                 return 1;
 362         if ((instr[0] & 0xE7)==0x07 && instr[0]!=0x0F)  /* pop  %segment-register */
 363                 return 1;
 364         switch (instr[0]) {
 365                 case 0x33:      /* xor GB,Ev */
 366                         return 1+1;
 367                 case 0x64:      /* prefix %fs */
 368                         return instruction_length(instr+1);
 369                 case 0x68:      /* push $quad-byte */
 370                         return 1+4;
 371                 case 0x6A:      /* push $single-byte */
 372                         return 1+1;
 373                 case 0x80:
 374                         switch (instr[1]) {
 375                                 case 0x3D:      /* cmpb $byte,immediate-quad-indirect */
 376                                         return 1+1+4+1; /* 80 3D immediate-quad-indirect byte */
 377                                 default: g_assert_not_reached();
 378                                 }
 379                 case 0x83:
 380                         switch (instr[1]) {
 381                                 case 0x01:      /* addl $byte,(%ecx) */
 382                                         return 1+1+1;
 383                                 case 0x3D:      /* cmpl $byte,immediate-quad-indirect */
 384                                         return 1+1+4+1; /* 83 3D immediate-quad-indirect byte */
 385                                 default: g_assert_not_reached();
 386                                 }
 387                 case 0x8A:      /* mov ??,?? */
 388                 case 0x8B:      /* mov Gb,Eb */
 389                         switch (instr[1]) {
 390                                 case 0x0D:      /* mov immediate-quad-indirect,%ecx */
 391                                         return 1+1+4;
 392                                 case 0x15:      /* mov immediate-quad-indirect,%edx */
 393                                         return 1+1+4;
 394                                 case 0x44:      /* mov #offset(%reg,%reg,#mult),%reg */
 395                                 case 0x4C:      /* mov #offset(%reg,#mult),%reg */
 396                                 case 0x54:      /* mov #offset(%reg,#mult),%reg */
 397                                         return 1+1+1+1; /* 8B 44 address-mode offset */
 398                                 default: g_assert_not_reached();
 399                                 }
 400                 case 0x8D:      /* lea Gb,M */
 401                         switch (instr[1]) {
 402                                 case 0x44:      /* mov #offset(%reg,%reg,#mult),%reg */
 403                                         return 4;       /* 8B 44 address-mode offset */
 404                                 default: g_assert_not_reached();
 405                                 }
 406                 case 0x8F:      /* lea Gb,M */
 407                         switch (instr[1]) {
 408                                 case 0x04:
 409                                         switch (instr[2]) {
 410                                                 case 0x24:      /* popl (%esp,1) */
 411                                                         return 3;
 412                                                 default: g_assert_not_reached();
 413                                                 }
 414                                 default: g_assert_not_reached();
 415                                 }
 416                 case 0x9C:      /* pushf */
 417                         return 1;
 418                 case 0x9D:      /* popf */
 419                         return 1;
 420                 case 0xA1:      /* mov immediate-quad-indirect,%eax */
 421                         return 1+4;
 422                 case 0xB8:      /* mov $immediate-quad,%eax */
 423                         return 1+4;
 424                 case 0xC2:      /* ret $immediate-double */
 425                         return 1+2;
 426                 case 0xCC:      /* int $0x3 */
 427                         return 1;
 428                 case 0xFA:      /* cli */
 429                         return 1;
 430                 case 0xFB:      /* sti */
 431                         return 1;
 432                 case 0xFF:      /* inc/dec Ev */
 433                         return 2;
 434                 default: g_assert_not_reached();
 435                 }
 436         g_assert_not_reached(); /* TODO:fill the table */
 437         /* NOTREACHED */
 438         return 0;
 439 }
 440
 441
 442         /* A lot of offsets in the structures are relative to ModuleObject->Base */
 443 #define MODULEOBJECT_BASE_OFFSET_PLUS(addr) ((gpointer)((char *)addr+(ptrdiff_t)ModuleObject->Base))
 444
 445 static void captive_ModuleList_patch_function_disable
 446                 (CHAR *funcname,PVOID *ExportAddressp,MODULE_OBJECT *ModuleObject /* user_data */)
 447 {
 448 PVOID ExportAddress;
 449
 450         g_return_if_fail(funcname!=NULL);
 451         g_return_if_fail(ExportAddressp!=NULL);
 452         g_return_if_fail(ModuleObject!=NULL);
 453
 454         ExportAddress=(PVOID)MODULEOBJECT_BASE_OFFSET_PLUS(*ExportAddressp);
 455         g_return_if_fail(ExportAddress!=NULL);
 456
 457         /* Some alised name; safe to ignore as we checked for possible W32 binary 0xF4
 458          * hits during our initialization in captive_ModuleList_patch().
 459          */
 460         if (0xF4 /* hlt */ ==*(guint8 *)ExportAddress)
 461                 return;
 462
 463         captive_ModuleList_function_disable_hash_init();
 464
 465         *(guint8 *)ExportAddress=0xF4; /* hlt */
 466         /* We may get aliased here; already existing entry is therefore allowed. */
 467         g_hash_table_insert(captive_ModuleList_function_disable_hash,
 468                         ExportAddress,  /* key */
 469                         funcname);      /* value */
 470 }
 471
 472
 473 /**
 474  * captive_ModuleList_patch:
 475  * @FullName_utf8: String to find #PMODULE_OBJECT by #FullName.
 476  * @...: (const gchar *sym_name,void (*sym_val)(void),struct captive_ModuleList_patchpoint *patchpoint) symbol list terminated by %NULL.
 477  *
 478  * Patches existing @FullName_utf8 module to use for function named #sym_name
 479  * pointer to the handler #sym_val. If #patchpoint is not %NULL it gets assigned the original
 480  * pointer value (used for %pass keyword in #exports.captivesym).
 481  *
 482  * Put here 0xF4 'hlt' instead of 0xCC 'int $0x3; breakpoint'
 483  * as 'hlt' will generate handled SIGSEGV instead of SIGTRAP which
 484  * is used by gdb(1) during debugging.
 485  * See also libcaptive/ps/signal.c/ sigaction_SIGSEGV().
 486  *
 487  * Returns: %TRUE if the module was successfuly added.
 488  */
 489 gboolean captive_ModuleList_patch(const gchar *FullName_utf8,...)
 490 {
 491 MODULE_OBJECT *ModuleObject;
 492 va_list ap;
 493 IMAGE_EXPORT_DIRECTORY *ExportDir;
 494 ptrdiff_t *NameList;    /* filled by sym_name; MODULEOBJECT_BASE_OFFSET_PLUS()ed */
 495 WORD *OrdinalList;      /* linear list - libcaptive doesn't support Ordinals */
 496 ptrdiff_t *FunctionList;        /* filled by sym_val; MODULEOBJECT_BASE_OFFSET_PLUS()ed */
 497 ULONG ExportDirSize;
 498 USHORT Idx;
 499 PVOID ExportAddress,*ExportAddressp;
 500 const gchar *sym_name;
 501 void (*sym_val)(void);
 502 struct captive_ModuleList_patchpoint *patchpoint;
 503 GHashTable *exportdir_hash;
 504 gboolean errbool;
 505
 506         g_return_val_if_fail(FullName_utf8!=NULL,FALSE);
 507
 508         captive_ModuleList_patchpoint_hash_init();
 509
 510         ModuleObject=LdrGetModuleObject(captive_utf8_to_UnicodeString_alloca(g_path_get_basename(FullName_utf8)));
 511         g_return_val_if_fail(ModuleObject!=NULL,FALSE);
 512
 513         ExportDir=(PIMAGE_EXPORT_DIRECTORY)RtlImageDirectoryEntryToData(ModuleObject->Base,
 514                         TRUE,IMAGE_DIRECTORY_ENTRY_EXPORT,&ExportDirSize);
 515         g_return_val_if_fail(ExportDir!=NULL,FALSE);
 516
 517         NameList    =MODULEOBJECT_BASE_OFFSET_PLUS(ExportDir->AddressOfNames);
 518         OrdinalList =MODULEOBJECT_BASE_OFFSET_PLUS(ExportDir->AddressOfNameOrdinals);
 519         FunctionList=MODULEOBJECT_BASE_OFFSET_PLUS(ExportDir->AddressOfFunctions);
 520
 521         /* map (CHAR *)funcname->(PVOID *)ExportAddressp */
 522         exportdir_hash=g_hash_table_new(g_str_hash,g_str_equal);
 523
 524         /* Initialize 'exportdir_hash' by all W32 exported functions. */
 525         for (Idx=0;Idx<ExportDir->NumberOfNames;Idx++) {
 526 CHAR *funcname=MODULEOBJECT_BASE_OFFSET_PLUS(NameList[Idx]);
 527
 528                 ExportAddressp=(PVOID *)(FunctionList+OrdinalList[Idx]);
 529                 ExportAddress=(PVOID)MODULEOBJECT_BASE_OFFSET_PLUS(*ExportAddressp);
 530                 if (0xF4 /* hlt */ ==*(guint8 *)ExportAddress) {
 531                         /* FIXME: 'data' type symbols should be permitted to have 0xF4 byte */
 532                         g_error("%s: Function already patched although we did not touch it yet: %s",G_STRLOC,funcname);
 533                         g_assert_not_reached();
 534                         }
 535                 g_assert(NULL==g_hash_table_lookup(exportdir_hash,funcname));
 536                 g_hash_table_insert(exportdir_hash,
 537                                 funcname,       /* key */
 538                                 ExportAddressp);        /* value */
 539                 }
 540
 541         /* Patch wished functions and remove them from 'exportdir_hash'. */
 542         va_start(ap,FullName_utf8);
 543         while (captive_va_arg(sym_name,ap)) {
 544                 captive_va_arg(sym_val ,ap);
 545                 /* 'sym_val' may be NULL if 'data' type && "pass"ed */
 546                 captive_va_arg(patchpoint,ap);  /* 'data' type if ==NULL */
 547                 ExportAddressp=g_hash_table_lookup(exportdir_hash,sym_name);
 548                 if (ExportAddressp==NULL) {
 549                         g_error("%s: Function not found for patchpoint: %s",G_STRLOC,sym_name);
 550                         g_assert_not_reached();
 551                         }
 552                 errbool=g_hash_table_remove(exportdir_hash,sym_name);
 553                 g_assert(errbool==TRUE);
 554                 if (!sym_val) { /* 'data' type && "pass"ed => do not corrupt it by 0xF4 */
 555                         g_assert(!patchpoint);
 556                         continue;
 557                         }
 558                 ExportAddress=(PVOID)MODULEOBJECT_BASE_OFFSET_PLUS(*ExportAddressp);
 559                 *ExportAddressp=(PVOID)MODULEOBJECT_BASE_OFFSET_MINUS(sym_val);
 560                 if (((ULONG)ExportAddress >= (ULONG)ExportDir) &&
 561                                 ((ULONG)ExportAddress <  (ULONG)ExportDir + ExportDirSize))
 562                         g_assert_not_reached(); /* LdrPEFixupForward() needed */
 563                 if (!patchpoint) /* 'data' type && !"pass"ed => do not corrupt it by 0xF4 */
 564                         continue;
 565                 patchpoint->orig_w32_func=ExportAddress;
 566                 if (0xF4 /* hlt */ ==*patchpoint->orig_w32_func)        /* Already patched by name-aliased function? */
 567                         continue;
 568                 g_assert(0xF4 /* hlt */ !=*patchpoint->orig_w32_func);
 569                 patchpoint->orig_w32_2ndinstr=patchpoint->orig_w32_func
 570                                 +instruction_length((guint8 *)patchpoint->orig_w32_func);
 571                 g_assert(0xF4 /* hlt */ !=*patchpoint->orig_w32_2ndinstr);
 572                 patchpoint->wrap_wrap_func=sym_val;
 573                 patchpoint->orig_w32_func_byte=*patchpoint->orig_w32_func;
 574                 patchpoint->orig_w32_2ndinstr_byte=*patchpoint->orig_w32_2ndinstr;
 575                 patchpoint->through_w32_func=FALSE;
 576                 g_assert(NULL==g_hash_table_lookup(captive_ModuleList_patchpoint_hash,patchpoint->orig_w32_func));
 577                 g_hash_table_insert(captive_ModuleList_patchpoint_hash,
 578                                 patchpoint->orig_w32_func,      /* key */
 579                                 patchpoint);    /* value */
 580                 g_assert(NULL==g_hash_table_lookup(captive_ModuleList_patchpoint_hash,patchpoint->orig_w32_2ndinstr));
 581                 g_hash_table_insert(captive_ModuleList_patchpoint_hash,
 582                                 patchpoint->orig_w32_2ndinstr,  /* key */
 583                                 patchpoint);    /* value */
 584                 *(guint8 *)ExportAddress=0xF4;  /* hlt */
 585                 }
 586         va_end(ap);
 587
 588         /* The remaining entries of 'exportdir_hash' are W32 native functions
 589          * unspecified by .captivesym file; we patch them as not-implemented ones.
 590          */
 591         g_hash_table_foreach(exportdir_hash,
 592                         (GHFunc)captive_ModuleList_patch_function_disable,      /* func */
 593                         ModuleObject);  /* used_data; unused */
 594
 595         g_hash_table_destroy(exportdir_hash);
 596
 597 #undef MODULEOBJECT_BASE_OFFSET_PLUS    /* no longer valid */
 598 #undef MODULEOBJECT_BASE_OFFSET_MINUS   /* no longer valid */
 599         return TRUE;
 600 }
 601
 602
 603 struct captive_ModuleList_patchpoint *captive_ModuleList_patchpoint_find(gconstpointer ExportAddress)
 604 {
 605 struct captive_ModuleList_patchpoint *r;
 606
 607         g_return_val_if_fail(ExportAddress!=NULL,NULL);
 608
 609         captive_ModuleList_patchpoint_hash_init();
 610
 611         r=g_hash_table_lookup(captive_ModuleList_patchpoint_hash,ExportAddress);
 612         g_return_val_if_fail(r!=NULL,NULL);
 613         g_assert(r->orig_w32_func==ExportAddress || r->orig_w32_2ndinstr==ExportAddress);
 614
 615         return r;
 616 }
 617
 618
 619 G_CONST_RETURN gchar *captive_ModuleList_function_disable_find(gconstpointer ExportAddress)
 620 {
 621         g_return_val_if_fail(ExportAddress!=NULL,NULL);
 622
 623         return g_hash_table_lookup(captive_ModuleList_function_disable_hash,ExportAddress);     /* funcname */
 624 }
 625
 626
 627 void *captive_Module_GetExportAddress(const gchar *ModuleName_utf8,const gchar *FunctionName)
 628 {
 629 MODULE_OBJECT *ModuleObject;
 630 void *r;
 631
 632         g_return_val_if_fail(ModuleName_utf8!=NULL,NULL);
 633         g_return_val_if_fail(FunctionName!=NULL,NULL);
 634
 635         ModuleObject=LdrGetModuleObject(captive_utf8_to_UnicodeString_alloca(g_path_get_basename(ModuleName_utf8)));
 636         g_return_val_if_fail(ModuleObject!=NULL,NULL);
 637
 638         r=LdrGetExportAddress(
 639                         ModuleObject,   /* ModuleObject */
 640                         (/* de-const */char *)FunctionName,     /* Name */
 641                         -1);    /*Hint*/
 642         g_return_val_if_fail(r!=NULL,NULL);
 643
 644         return r;
 645 }