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  * @options_module: #captive_options_module structure describing the module to load.
 125  * Loading of already loaded module is forbidden.
 126  * @ModuleObjectp: 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  * @options_module: #captive_options_module structure describing the module to load.
 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=(NTSTATUS)captive_stdcall_call_8((CaptiveStdCallFunc8)DriverEntry,
 224                         DriverEntry_DriverObject,
 225                         DriverEntry_RegistryPath);
 226         if (!NT_SUCCESS(err))
 227                 goto err_LdrUnloadModule;
 228
 229         /* assumed STATUS_SUCCESS */
 230         return err;
 231
 232 err_LdrUnloadModule:
 233         /* errors ignored */
 234         LdrUnloadModule(*ModuleObjectp);
 235         *ModuleObjectp=NULL;
 236 /* err: */
 237         g_return_val_if_reached(err);
 238 }
 239
 240
 241 /**
 242  * captive_ModuleList_add_builtin:
 243  * @FullName_utf8: String to fill in #PMODULE_OBJECT->FullName.
 244  * @...: (const gchar *sym_name,void *sym_val) symbol list terminated by %NULL.
 245  *
 246  * Adds simulated built-in module to #ModuleListHead module list.
 247  * It can be used for the functionality of reactos/ntoskrnl/ldr/loader.c/LdrInitModuleManagement().
 248  * libcaptive does not support Ordinals - we just pretend liner (%0-based)
 249  * Ordinal numbers of the functions in given @... stdargs order.
 250  *
 251  * Returns: %TRUE if the module was successfuly added.
 252  */
 253 gboolean captive_ModuleList_add_builtin(const gchar *FullName_utf8,...)
 254 {
 255 MODULE_OBJECT *ModuleObject;
 256 BOOLEAN errbool;
 257 va_list ap;
 258 const gchar *sym_name;
 259 const void *sym_val;
 260 gchar *basename_utf8;
 261 IMAGE_DOS_HEADER *DosHeader;
 262 IMAGE_NT_HEADERS *NTHeaders;
 263 IMAGE_EXPORT_DIRECTORY *ExportDir;
 264 guint symi,symN;        /* index,number of passed stdarg sym_name/sym_val pairs */
 265 ptrdiff_t *NameList;    /* filled by sym_name; MODULEOBJECT_BASE_OFFSET_MINUS()ed */
 266 WORD *OrdinalList;      /* linear list - libcaptive doesn't support Ordinals */
 267 ptrdiff_t *FunctionList;        /* filled by sym_val; MODULEOBJECT_BASE_OFFSET_MINUS()ed */
 268
 269         g_return_val_if_fail(FullName_utf8!=NULL,FALSE);
 270
 271         captive_new0(ModuleObject);
 272         /* A lot of offsets in the structures are relative to ModuleObject->Base */
 273 #define MODULEOBJECT_BASE_OFFSET_MINUS(addr) ((ptrdiff_t)((char *)addr-(char *)ModuleObject->Base))
 274
 275         ModuleObject->Flags = MODULE_FLAG_PE;
 276
 277         /* fill ModuleObject->FullName
 278          * ModuleObject->FullName should be probably "\\SYSTEM32\\..." style but
 279          * we put there '/'-based UNIX filenames in libcaptive.
 280          */
 281         errbool=RtlCreateUnicodeString(&ModuleObject->FullName,captive_utf8_to_UnicodeString_alloca(FullName_utf8)->Buffer);
 282         if (!errbool) {
 283                 g_error("captive_ModuleList_add_builtin: RtlCreateUnicodeString()==FALSE");
 284                 goto err_g_free_ModuleObject;
 285                 }
 286
 287         /* fill ModuleObject->BaseName
 288          * reactos/ntoskrnl/ldr/loader.c/LdrpBuildModuleBaseName() does this one
 289          * but it is 'static' for that file and also it is stricly backslash based.
 290          * ModuleObject->FullName should be probably "\\SYSTEM32\\..." style but
 291          * we put there '/'-based UNIX filenames in libcaptive.
 292          */
 293         basename_utf8=g_path_get_basename(FullName_utf8);
 294         errbool=RtlCreateUnicodeString(&ModuleObject->BaseName,captive_utf8_to_UnicodeString_alloca(basename_utf8)->Buffer);
 295         g_free(basename_utf8);
 296         if (!errbool) {
 297                 g_error("captive_ModuleList_add_builtin: RtlCreateUnicodeString()==FALSE");
 298                 goto err_g_free_ModuleObject;
 299                 }
 300
 301         /* We must satisfy reactos/ntoskrnl/ldr/rtl.c/RtlImageDirectoryEntryToData(,,IMAGE_DIRECTORY_ENTRY_EXPORT)
 302          * prepare module headers
 303          */
 304         captive_new0(DosHeader);
 305         ModuleObject->Base=DosHeader;   /* link DosHeader to ModuleObject */
 306         DosHeader->e_magic=IMAGE_DOS_MAGIC;
 307         captive_new0(NTHeaders);
 308         DosHeader->e_lfanew=MODULEOBJECT_BASE_OFFSET_MINUS(NTHeaders);  /* link NTHeaders to DosHeader */
 309         NTHeaders->Signature=IMAGE_PE_MAGIC;
 310         NTHeaders->OptionalHeader.NumberOfRvaAndSizes=IMAGE_DIRECTORY_ENTRY_EXPORT+1;
 311         NTHeaders->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT].Size
 312                         =sizeof(*ExportDir);    /* in bytes; just prevent LdrPEFixupForward() invocation */
 313         captive_new0(ExportDir);
 314         NTHeaders->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT].VirtualAddress
 315                         =MODULEOBJECT_BASE_OFFSET_MINUS(ExportDir);     /* link ExportDir to NTHeaders */
 316         ExportDir->Base=0;      /* base Ordinal number; Ordinals are not supported by libcaptive */
 317
 318         /* count the number of symbols */
 319         va_start(ap,FullName_utf8);
 320         for (symN=0;captive_va_arg(sym_name,ap);symN++)
 321                 captive_va_arg(sym_val,ap);
 322         va_end(ap);
 323         ExportDir->NumberOfNames=symN;
 324         ExportDir->NumberOfFunctions=symN;
 325
 326         /* allocate and link the symbol tables */
 327         captive_newn(NameList,symN);
 328         ExportDir->AddressOfNames=(PDWORD *)MODULEOBJECT_BASE_OFFSET_MINUS(NameList);   /* link NameList to ExportDir */
 329         captive_newn(OrdinalList,symN);
 330         ExportDir->AddressOfNameOrdinals=(PWORD *)MODULEOBJECT_BASE_OFFSET_MINUS(OrdinalList);  /* link OrdinalList to ExportDir */
 331         captive_newn(FunctionList,symN);
 332         ExportDir->AddressOfFunctions=(PDWORD *)MODULEOBJECT_BASE_OFFSET_MINUS(FunctionList);   /* link FunctionList to ExportDir */
 333
 334         /* fill in symbol tables */
 335         va_start(ap,FullName_utf8);
 336         for (symi=0;symi<symN;symi++) {
 337                 captive_va_arg(sym_name,ap);
 338                 captive_va_arg(sym_val ,ap);
 339                 NameList[symi]=MODULEOBJECT_BASE_OFFSET_MINUS(sym_name);
 340                 OrdinalList[symi]=symi; /* Ordinals are not supported by libcaptive */
 341                 FunctionList[symi]=MODULEOBJECT_BASE_OFFSET_MINUS(sym_val);
 342                 }
 343         va_end(ap);
 344
 345         /* successful module info build */
 346         InsertTailList(&ModuleListHead,&ModuleObject->ListEntry);
 347         return TRUE;
 348
 349 err_g_free_ModuleObject:
 350         g_free(ModuleObject);
 351 /* err */
 352         g_return_val_if_reached(FALSE);
 353 }
 354
 355
 356 static gsize instruction_length(const guint8 *instr)
 357 {
 358         if ((instr[0] & 0xF8)==0x50)    /* push %regular-register */
 359                 return 1;
 360         if ((instr[0] & 0xF8)==0x58)    /* pop  %regular-register */
 361                 return 1;
 362         if ((instr[0] & 0xE7)==0x06)    /* push %segment-register */
 363                 return 1;
 364         if ((instr[0] & 0xE7)==0x07 && instr[0]!=0x0F)  /* pop  %segment-register */
 365                 return 1;
 366         switch (instr[0]) {
 367                 case 0x33:      /* xor GB,Ev */
 368                         return 1+1;
 369                 case 0x64:      /* prefix %fs */
 370                         return instruction_length(instr+1);
 371                 case 0x68:      /* push $quad-byte */
 372                         return 1+4;
 373                 case 0x6A:      /* push $single-byte */
 374                         return 1+1;
 375                 case 0x80:
 376                         switch (instr[1]) {
 377                                 case 0x3D:      /* cmpb $byte,immediate-quad-indirect */
 378                                         return 1+1+4+1; /* 80 3D immediate-quad-indirect byte */
 379                                 case 0x7C:      /* cmpb $byte,#immediate(%reg,1) */
 380                                         return 1+1+1+1+1;       /* 80 7C address-mode immediate byte */
 381                                 default: g_assert_not_reached();
 382                                 }
 383                 case 0x83:
 384                         switch (instr[1]) {
 385                                 case 0x01:      /* addl $byte,(%ecx) */
 386                                         return 1+1+1;
 387                                 case 0x3D:      /* cmpl $byte,immediate-quad-indirect */
 388                                         return 1+1+4+1; /* 83 3D immediate-quad-indirect byte */
 389                                 case 0x7C:      /* cmpl $byte,#immediate(%reg,1) */
 390                                         return 1+1+1+1+1;       /* 80 7C address-mode immediate byte */
 391                                 default: g_assert_not_reached();
 392                                 }
 393                 case 0x8A:      /* mov ??,?? */
 394                 case 0x8B:      /* mov Gb,Eb */
 395                         switch (instr[1]) {
 396                                 case 0x0D:      /* mov immediate-quad-indirect,%ecx */
 397                                         return 1+1+4;
 398                                 case 0x15:      /* mov immediate-quad-indirect,%edx */
 399                                         return 1+1+4;
 400                                 case 0x44:      /* mov #offset(%reg,%reg,#mult),%reg */
 401                                 case 0x4C:      /* mov #offset(%reg,#mult),%reg */
 402                                 case 0x54:      /* mov #offset(%reg,#mult),%reg */
 403                                         return 1+1+1+1; /* 8B 44 address-mode offset */
 404                                 default: g_assert_not_reached();
 405                                 }
 406                 case 0x8D:      /* lea Gb,M */
 407                         switch (instr[1]) {
 408                                 case 0x44:      /* mov #offset(%reg,%reg,#mult),%reg */
 409                                         return 4;       /* 8B 44 address-mode offset */
 410                                 default: g_assert_not_reached();
 411                                 }
 412                 case 0x8F:      /* lea Gb,M */
 413                         switch (instr[1]) {
 414                                 case 0x04:
 415                                         switch (instr[2]) {
 416                                                 case 0x24:      /* popl (%esp,1) */
 417                                                         return 3;
 418                                                 default: g_assert_not_reached();
 419                                                 }
 420                                 default: g_assert_not_reached();
 421                                 }
 422                 case 0x9C:      /* pushf */
 423                         return 1;
 424                 case 0x9D:      /* popf */
 425                         return 1;
 426                 case 0xA1:      /* mov immediate-quad-indirect,%eax */
 427                         return 1+4;
 428                 case 0xB8:      /* mov $immediate-quad,%eax */
 429                         return 1+4;
 430                 case 0xC2:      /* ret $immediate-double */
 431                         return 1+2;
 432                 case 0xCC:      /* int $0x3 */
 433                         return 1;
 434                 case 0xF0:      /* lock prefix */
 435                         return 1+instruction_length(instr+1);
 436                 case 0xFA:      /* cli */
 437                         return 1;
 438                 case 0xFB:      /* sti */
 439                         return 1;
 440                 case 0xFF:      /* inc/dec Ev */
 441                         return 2;
 442                 default: g_assert_not_reached();
 443                 }
 444         g_assert_not_reached(); /* TODO:fill the table */
 445         /* NOTREACHED */
 446         return 0;
 447 }
 448
 449
 450         /* A lot of offsets in the structures are relative to ModuleObject->Base */
 451 #define MODULEOBJECT_BASE_OFFSET_PLUS(addr) ((gpointer)((char *)addr+(ptrdiff_t)ModuleObject->Base))
 452
 453 static void captive_ModuleList_patch_function_disable
 454                 (CHAR *funcname,PVOID *ExportAddressp,MODULE_OBJECT *ModuleObject /* user_data */)
 455 {
 456 PVOID ExportAddress;
 457
 458         g_return_if_fail(funcname!=NULL);
 459         g_return_if_fail(ExportAddressp!=NULL);
 460         g_return_if_fail(ModuleObject!=NULL);
 461
 462         ExportAddress=(PVOID)MODULEOBJECT_BASE_OFFSET_PLUS(*ExportAddressp);
 463         g_return_if_fail(ExportAddress!=NULL);
 464
 465         /* Some alised name; safe to ignore as we checked for possible W32 binary 0xF4
 466          * hits during our initialization in captive_ModuleList_patch().
 467          */
 468         if (0xF4 /* hlt */ ==*(guint8 *)ExportAddress)
 469                 return;
 470
 471         captive_ModuleList_function_disable_hash_init();
 472
 473         *(guint8 *)ExportAddress=0xF4; /* hlt */
 474         /* We may get aliased here; already existing entry is therefore allowed. */
 475         g_hash_table_insert(captive_ModuleList_function_disable_hash,
 476                         ExportAddress,  /* key */
 477                         funcname);      /* value */
 478 }
 479
 480
 481 /**
 482  * captive_ModuleList_patch:
 483  * @FullName_utf8: String to find #PMODULE_OBJECT by #FullName.
 484  * @...: (const gchar *sym_name,void (*sym_val)(void),struct captive_ModuleList_patchpoint *patchpoint) symbol list terminated by %NULL.
 485  *
 486  * Patches existing @FullName_utf8 module to use for function named #sym_name
 487  * pointer to the handler #sym_val. If #patchpoint is not %NULL it gets assigned the original
 488  * pointer value (used for %pass keyword in #exports.captivesym).
 489  *
 490  * Put here 0xF4 'hlt' instead of 0xCC 'int $0x3; breakpoint'
 491  * as 'hlt' will generate handled SIGSEGV instead of SIGTRAP which
 492  * is used by gdb(1) during debugging.
 493  * See also libcaptive/ps/signal.c/ sigaction_SIGSEGV().
 494  *
 495  * Returns: %TRUE if the module was successfuly added.
 496  */
 497 gboolean captive_ModuleList_patch(const gchar *FullName_utf8,...)
 498 {
 499 MODULE_OBJECT *ModuleObject;
 500 va_list ap;
 501 IMAGE_EXPORT_DIRECTORY *ExportDir;
 502 ptrdiff_t *NameList;    /* filled by sym_name; MODULEOBJECT_BASE_OFFSET_PLUS()ed */
 503 WORD *OrdinalList;      /* linear list - libcaptive doesn't support Ordinals */
 504 ptrdiff_t *FunctionList;        /* filled by sym_val; MODULEOBJECT_BASE_OFFSET_PLUS()ed */
 505 ULONG ExportDirSize;
 506 USHORT Idx;
 507 PVOID ExportAddress,*ExportAddressp;
 508 const gchar *sym_name;
 509 void (*sym_val)(void);
 510 struct captive_ModuleList_patchpoint *patchpoint,*patchpointpatch;
 511 GHashTable *exportdir_hash;
 512 gboolean errbool;
 513
 514         g_return_val_if_fail(FullName_utf8!=NULL,FALSE);
 515
 516         captive_ModuleList_patchpoint_hash_init();
 517
 518         ModuleObject=LdrGetModuleObject(captive_utf8_to_UnicodeString_alloca(g_path_get_basename(FullName_utf8)));
 519         g_return_val_if_fail(ModuleObject!=NULL,FALSE);
 520
 521         ExportDir=(PIMAGE_EXPORT_DIRECTORY)RtlImageDirectoryEntryToData(ModuleObject->Base,
 522                         TRUE,IMAGE_DIRECTORY_ENTRY_EXPORT,&ExportDirSize);
 523         g_return_val_if_fail(ExportDir!=NULL,FALSE);
 524
 525         NameList    =MODULEOBJECT_BASE_OFFSET_PLUS(ExportDir->AddressOfNames);
 526         OrdinalList =MODULEOBJECT_BASE_OFFSET_PLUS(ExportDir->AddressOfNameOrdinals);
 527         FunctionList=MODULEOBJECT_BASE_OFFSET_PLUS(ExportDir->AddressOfFunctions);
 528
 529         /* map (CHAR *)funcname->(PVOID *)ExportAddressp */
 530         exportdir_hash=g_hash_table_new(g_str_hash,g_str_equal);
 531
 532         /* Initialize 'exportdir_hash' by all W32 exported functions. */
 533         for (Idx=0;Idx<ExportDir->NumberOfNames;Idx++) {
 534 CHAR *funcname=MODULEOBJECT_BASE_OFFSET_PLUS(NameList[Idx]);
 535
 536                 ExportAddressp=(PVOID *)(FunctionList+OrdinalList[Idx]);
 537                 ExportAddress=(PVOID)MODULEOBJECT_BASE_OFFSET_PLUS(*ExportAddressp);
 538                 if (0xF4 /* hlt */ ==*(guint8 *)ExportAddress) {
 539                         /* FIXME: 'data' type symbols should be permitted to have 0xF4 byte */
 540                         g_error("%s: Function already patched although we did not touch it yet: %s",G_STRLOC,funcname);
 541                         g_assert_not_reached();
 542                         }
 543                 g_assert(NULL==g_hash_table_lookup(exportdir_hash,funcname));
 544                 g_hash_table_insert(exportdir_hash,
 545                                 funcname,       /* key */
 546                                 ExportAddressp);        /* value */
 547                 }
 548
 549         /* Patch wished functions and remove them from 'exportdir_hash'. */
 550         va_start(ap,FullName_utf8);
 551         while (captive_va_arg(sym_name,ap)) {
 552                 captive_va_arg(sym_val ,ap);
 553                 /* 'sym_val' may be NULL if 'data' type && "pass"ed */
 554                 captive_va_arg(patchpoint,ap);  /* 'data' type if ==NULL */
 555                 captive_va_arg(patchpointpatch,ap);     /* 'data' type or 'pass' in non-debug mode if ==NULL */
 556                 ExportAddressp=g_hash_table_lookup(exportdir_hash,sym_name);
 557                 if (ExportAddressp==NULL) {
 558                         g_message("%s: Function not found for patchpoint (ignoring): %s",G_STRLOC,sym_name);
 559                         continue;
 560                         }
 561                 errbool=g_hash_table_remove(exportdir_hash,sym_name);
 562                 g_assert(errbool==TRUE);
 563                 if (!sym_val) { /* 'data' type && "pass"ed => do not corrupt it by 0xF4 */
 564                         g_assert(!patchpoint);
 565                         continue;
 566                         }
 567                 ExportAddress=(PVOID)MODULEOBJECT_BASE_OFFSET_PLUS(*ExportAddressp);
 568                 *ExportAddressp=(PVOID)MODULEOBJECT_BASE_OFFSET_MINUS(sym_val);
 569                 if (((ULONG)ExportAddress >= (ULONG)ExportDir) &&
 570                                 ((ULONG)ExportAddress <  (ULONG)ExportDir + ExportDirSize))
 571                         g_assert_not_reached(); /* LdrPEFixupForward() needed */
 572                 if (!patchpoint) /* 'data' type && !"pass"ed => do not corrupt it by 0xF4 */
 573                         continue;
 574                 patchpoint->orig_w32_func=ExportAddress;
 575                 if (!patchpointpatch)   /* 'pass' in non-debug mode */
 576                         continue;
 577                 if (0xF4 /* hlt */ ==*patchpointpatch->orig_w32_func)   /* Already patched by name-aliased function? */
 578                         continue;
 579                 g_assert(0xF4 /* hlt */ !=*patchpointpatch->orig_w32_func);
 580                 patchpointpatch->orig_w32_2ndinstr=patchpointpatch->orig_w32_func
 581                                 +instruction_length((guint8 *)patchpointpatch->orig_w32_func);
 582                 g_assert(0xF4 /* hlt */ !=*patchpointpatch->orig_w32_2ndinstr);
 583                 patchpointpatch->wrap_wrap_func=sym_val;
 584                 patchpointpatch->orig_w32_func_byte=*patchpointpatch->orig_w32_func;
 585                 patchpointpatch->orig_w32_2ndinstr_byte=*patchpointpatch->orig_w32_2ndinstr;
 586                 patchpointpatch->through_w32_func=FALSE;
 587                 g_assert(NULL==g_hash_table_lookup(captive_ModuleList_patchpoint_hash,patchpointpatch->orig_w32_func));
 588                 g_hash_table_insert(captive_ModuleList_patchpoint_hash,
 589                                 patchpointpatch->orig_w32_func, /* key */
 590                                 patchpointpatch);       /* value */
 591                 g_assert(NULL==g_hash_table_lookup(captive_ModuleList_patchpoint_hash,patchpointpatch->orig_w32_2ndinstr));
 592                 g_hash_table_insert(captive_ModuleList_patchpoint_hash,
 593                                 patchpointpatch->orig_w32_2ndinstr,     /* key */
 594                                 patchpointpatch);       /* value */
 595                 *(guint8 *)ExportAddress=0xF4;  /* hlt */
 596                 }
 597         va_end(ap);
 598
 599         /* The remaining entries of 'exportdir_hash' are W32 native functions
 600          * unspecified by .captivesym file; we patch them as not-implemented ones.
 601          */
 602         g_hash_table_foreach(exportdir_hash,
 603                         (GHFunc)captive_ModuleList_patch_function_disable,      /* func */
 604                         ModuleObject);  /* used_data; unused */
 605
 606         g_hash_table_destroy(exportdir_hash);
 607
 608 #undef MODULEOBJECT_BASE_OFFSET_PLUS    /* no longer valid */
 609 #undef MODULEOBJECT_BASE_OFFSET_MINUS   /* no longer valid */
 610         return TRUE;
 611 }
 612
 613
 614 struct captive_ModuleList_patchpoint *captive_ModuleList_patchpoint_find(gconstpointer ExportAddress)
 615 {
 616 struct captive_ModuleList_patchpoint *r;
 617
 618         g_return_val_if_fail(ExportAddress!=NULL,NULL);
 619
 620         captive_ModuleList_patchpoint_hash_init();
 621
 622         r=g_hash_table_lookup(captive_ModuleList_patchpoint_hash,ExportAddress);
 623         g_return_val_if_fail(r!=NULL,NULL);
 624         g_assert(r->orig_w32_func==ExportAddress || r->orig_w32_2ndinstr==ExportAddress);
 625
 626         return r;
 627 }
 628
 629
 630 G_CONST_RETURN gchar *captive_ModuleList_function_disable_find(gconstpointer ExportAddress)
 631 {
 632         g_return_val_if_fail(ExportAddress!=NULL,NULL);
 633
 634         return g_hash_table_lookup(captive_ModuleList_function_disable_hash,ExportAddress);     /* funcname */
 635 }
 636
 637
 638 void *captive_Module_GetExportAddress(const gchar *ModuleName_utf8,const gchar *FunctionName)
 639 {
 640 MODULE_OBJECT *ModuleObject;
 641 void *r;
 642
 643         g_return_val_if_fail(ModuleName_utf8!=NULL,NULL);
 644         g_return_val_if_fail(FunctionName!=NULL,NULL);
 645
 646         ModuleObject=LdrGetModuleObject(captive_utf8_to_UnicodeString_alloca(g_path_get_basename(ModuleName_utf8)));
 647         g_return_val_if_fail(ModuleObject!=NULL,NULL);
 648
 649         r=LdrGetExportAddress(
 650                         ModuleObject,   /* ModuleObject */
 651                         (/* de-const */char *)FunctionName,     /* Name */
 652                         -1);    /*Hint*/
 653         g_return_val_if_fail(r!=NULL,NULL);
 654
 655         return r;
 656 }