dlls/crypt32/protectdata.c

   1 /*
   2  * Copyright 2005 Kees Cook <kees@outflux.net>
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library 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 GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  17  */
  18
  19
  20 /*
  21  * The Win32 CryptProtectData and CryptUnprotectData functions are meant
  22  * to provide a mechanism for encrypting data on a machine where other users
  23  * of the system can't be trusted.  It is used in many examples as a way
  24  * to store username and password information to the registry, but store
  25  * it not in the clear.
  26  *
  27  * The encryption is symmetric, but the method is unknown.  However, since
  28  * it is keyed to the machine and the user, it is unlikely that the values
  29  * would be portable.  Since programs must first call CryptProtectData to
  30  * get a cipher text, the underlying system doesn't have to exactly
  31  * match the real Windows version.  However, attempts have been made to
  32  * at least try to look like the Windows version, including guesses at the
  33  * purpose of various portions of the "opaque data blob" that is used.
  34  *
  35  */
  36
  37 #include <stdarg.h>
  38 #include <stdio.h>
  39 #include <string.h>
  40 #include <stdlib.h>
  41
  42 #include "windef.h"
  43 #include "winbase.h"
  44 #include "wincrypt.h"
  45 #include "wine/debug.h"
  46
  47 WINE_DEFAULT_DEBUG_CHANNEL(crypt);
  48
  49 #define CRYPT32_PROTECTDATA_PROV      PROV_RSA_FULL
  50 #define CRYPT32_PROTECTDATA_HASH_CALG CALG_SHA1
  51 #define CRYPT32_PROTECTDATA_HASH_LEN  160
  52 #define CRYPT32_PROTECTDATA_KEY_CALG  CALG_3DES
  53 #define CRYPT32_PROTECTDATA_KEY_LEN   168
  54 #define CRYPT32_PROTECTDATA_SALT_LEN  16
  55
  56 static const BYTE crypt32_protectdata_secret[] = {
  57     'I','\'','m',' ','h','u','n','t','i','n','g',' ',
  58     'w','a','b','b','i','t','s',0
  59 };
  60
  61 /*
  62  * The data format returned by the real Windows CryptProtectData seems
  63  * to be something like this:
  64
  65  DWORD  count0;         - how many "info0_*[16]" blocks follow (was always 1)
  66  BYTE   info0_0[16];    - unknown information - persistent across invocations,
  67  ...                      reboots, password changes, and users
  68  DWORD  count1;         - how many "info1_*[16]" blocks follow (was always 1)
  69  BYTE   info1_0[16];    - unknown information - unique to each user, but
  70  ...                      persistent across reboots and password changes
  71  DWORD  null0;          - NULL "end of records"?
  72  DWORD  str_len;        - byte length of WCHAR string including term
  73  BYTE   str[str_len];   - The "dataDescription" value as a NULL-terminated
  74                           little-endian WCHAR string
  75  ALG_ID cipher_alg;     - cipher algo - was CALG_3DES
  76  DWORD  cipher_key_len; - cipher key bit length - was 0xa8==168
  77  DWORD  data_len;       - length of data (was 16 in samples)
  78  BYTE   data[data_len]; - unknown data (fingerprint?)
  79  DWORD  null1;          - NULL ?
  80  ALG_ID hash_alg;       - hash algo - was CALG_SHA1
  81  DWORD  hash_len;       - bit length of hash - was 0xa0==160
  82  DWORD  salt_len;       - length of salt(?) data
  83  BYTE   salt[salt_len]; - salt(?) for symmetric encryption
  84  DWORD  cipher_len;     - length of cipher(?) data - was close to plain len
  85  BYTE   cipher[cipher_len]; - cipher text?
  86  DWORD  crc_len;        - length of fingerprint(?) data - was 20 byte==160b SHA1
  87  BYTE   crc[crc_len];   - fingerprint of record?
  88
  89  * The data structures used in Wine are modelled after this guess.
  90  */
  91
  92 struct protect_data_t
  93 {
  94     DWORD       count0;
  95     DATA_BLOB   info0;        /* using this to hold crypt_magic_str */
  96     DWORD       count1;
  97     DATA_BLOB   info1;
  98     DWORD       null0;
  99     WCHAR *     szDataDescr;  /* serialized differently than the DATA_BLOBs */
 100     ALG_ID      cipher_alg;
 101     DWORD       cipher_key_len;
 102     DATA_BLOB   data0;
 103     DWORD       null1;
 104     ALG_ID      hash_alg;
 105     DWORD       hash_len;
 106     DATA_BLOB   salt;
 107     DATA_BLOB   cipher;
 108     DATA_BLOB   fingerprint;
 109 };
 110
 111 /* this is used to check if an incoming structure was built by Wine */
 112 static const char crypt_magic_str[] = "Wine Crypt32 ok";
 113
 114 /* debugging tool to print strings of hex chars */
 115 static const char *
 116 hex_str(const unsigned char *p, int n)
 117 {
 118     const char * ptr;
 119     char report[80];
 120     int r=-1;
 121     report[0]='\0';
 122     ptr = wine_dbg_sprintf("%s","");
 123     while (--n >= 0)
 124     {
 125         if (r++ % 20 == 19)
 126         {
 127             ptr = wine_dbg_sprintf("%s%s",ptr,report);
 128             report[0]='\0';
 129         }
 130         sprintf(report+strlen(report),"%s%02x", r ? "," : "", *p++);
 131     }
 132     return wine_dbg_sprintf("%s%s",ptr,report);
 133 }
 134
 135 #define TRACE_DATA_BLOB(blob) do { \
 136     TRACE("%s cbData: %u\n", #blob ,(unsigned int)((blob)->cbData)); \
 137     TRACE("%s pbData @ %p:%s\n", #blob ,(blob)->pbData, \
 138           hex_str((blob)->pbData, (blob)->cbData)); \
 139 } while (0)
 140
 141 static
 142 void serialize_dword(DWORD value,BYTE ** ptr)
 143 {
 144     /*TRACE("called\n");*/
 145
 146     memcpy(*ptr,&value,sizeof(DWORD));
 147     *ptr+=sizeof(DWORD);
 148 }
 149
 150 static
 151 void serialize_string(const BYTE *str, BYTE **ptr, DWORD len, DWORD width,
 152                       BOOL prepend_len)
 153 {
 154     /*TRACE("called %ux%u\n",(unsigned int)len,(unsigned int)width);*/
 155
 156     if (prepend_len)
 157     {
 158         serialize_dword(len,ptr);
 159     }
 160     memcpy(*ptr,str,len*width);
 161     *ptr+=len*width;
 162 }
 163
 164 static
 165 BOOL unserialize_dword(const BYTE *ptr, DWORD *index, DWORD size, DWORD *value)
 166 {
 167     /*TRACE("called\n");*/
 168
 169     if (!ptr || !index || !value) return FALSE;
 170
 171     if (*index+sizeof(DWORD)>size)
 172     {
 173         return FALSE;
 174     }
 175
 176     memcpy(value,&(ptr[*index]),sizeof(DWORD));
 177     *index+=sizeof(DWORD);
 178
 179     return TRUE;
 180 }
 181
 182 static
 183 BOOL unserialize_string(const BYTE *ptr, DWORD *index, DWORD size,
 184                         DWORD len, DWORD width, BOOL inline_len,
 185                         BYTE ** data, DWORD * stored)
 186 {
 187     /*TRACE("called\n");*/
 188
 189     if (!ptr || !data) return FALSE;
 190
 191     if (inline_len) {
 192         if (!unserialize_dword(ptr,index,size,&len))
 193             return FALSE;
 194     }
 195
 196     if (*index+len*width>size)
 197     {
 198         return FALSE;
 199     }
 200
 201     if (!(*data = CryptMemAlloc( len*width)))
 202     {
 203         return FALSE;
 204     }
 205
 206     memcpy(*data,&(ptr[*index]),len*width);
 207     if (stored)
 208     {
 209         *stored = len;
 210     }
 211     *index+=len*width;
 212
 213     return TRUE;
 214 }
 215
 216 static
 217 BOOL serialize(const struct protect_data_t *pInfo, DATA_BLOB *pSerial)
 218 {
 219     BYTE * ptr;
 220     DWORD dwStrLen;
 221     DWORD dwStruct;
 222
 223     TRACE("called\n");
 224
 225     if (!pInfo || !pInfo->szDataDescr || !pSerial ||
 226         !pInfo->info0.pbData || !pInfo->info1.pbData ||
 227         !pInfo->data0.pbData || !pInfo->salt.pbData ||
 228         !pInfo->cipher.pbData || !pInfo->fingerprint.pbData)
 229     {
 230         return FALSE;
 231     }
 232
 233     if (pInfo->info0.cbData!=16)
 234     {
 235         ERR("protect_data_t info0 not 16 bytes long\n");
 236     }
 237
 238     if (pInfo->info1.cbData!=16)
 239     {
 240         ERR("protect_data_t info1 not 16 bytes long\n");
 241     }
 242
 243     dwStrLen=lstrlenW(pInfo->szDataDescr);
 244
 245     pSerial->cbData=0;
 246     pSerial->cbData+=sizeof(DWORD)*8; /* 8 raw DWORDs */
 247     pSerial->cbData+=sizeof(DWORD)*4; /* 4 BLOBs with size */
 248     pSerial->cbData+=pInfo->info0.cbData;
 249     pSerial->cbData+=pInfo->info1.cbData;
 250     pSerial->cbData+=(dwStrLen+1)*sizeof(WCHAR) + 4; /* str, null, size */
 251     pSerial->cbData+=pInfo->data0.cbData;
 252     pSerial->cbData+=pInfo->salt.cbData;
 253     pSerial->cbData+=pInfo->cipher.cbData;
 254     pSerial->cbData+=pInfo->fingerprint.cbData;
 255
 256     /* save the actual structure size */
 257     dwStruct = pSerial->cbData;
 258     /* There may be a 256 byte minimum, but I can't prove it. */
 259     /*if (pSerial->cbData<256) pSerial->cbData=256;*/
 260
 261     pSerial->pbData=LocalAlloc(LPTR,pSerial->cbData);
 262     if (!pSerial->pbData) return FALSE;
 263
 264     ptr=pSerial->pbData;
 265
 266     /* count0 */
 267     serialize_dword(pInfo->count0,&ptr);
 268     /*TRACE("used %u\n",ptr-pSerial->pbData);*/
 269
 270     /* info0 */
 271     serialize_string(pInfo->info0.pbData,&ptr,
 272                      pInfo->info0.cbData,sizeof(BYTE),FALSE);
 273     /*TRACE("used %u\n",ptr-pSerial->pbData);*/
 274
 275     /* count1 */
 276     serialize_dword(pInfo->count1,&ptr);
 277     /*TRACE("used %u\n",ptr-pSerial->pbData);*/
 278
 279     /* info1 */
 280     serialize_string(pInfo->info1.pbData,&ptr,
 281                      pInfo->info1.cbData,sizeof(BYTE),FALSE);
 282     /*TRACE("used %u\n",ptr-pSerial->pbData);*/
 283
 284     /* null0 */
 285     serialize_dword(pInfo->null0,&ptr);
 286     /*TRACE("used %u\n",ptr-pSerial->pbData);*/
 287
 288     /* szDataDescr */
 289     serialize_string((BYTE*)pInfo->szDataDescr,&ptr,
 290                      (dwStrLen+1)*sizeof(WCHAR),sizeof(BYTE),TRUE);
 291     /*TRACE("used %u\n",ptr-pSerial->pbData);*/
 292
 293     /* cipher_alg */
 294     serialize_dword(pInfo->cipher_alg,&ptr);
 295     /*TRACE("used %u\n",ptr-pSerial->pbData);*/
 296     /* cipher_key_len */
 297     serialize_dword(pInfo->cipher_key_len,&ptr);
 298     /*TRACE("used %u\n",ptr-pSerial->pbData);*/
 299
 300     /* data0 */
 301     serialize_string(pInfo->data0.pbData,&ptr,
 302                      pInfo->data0.cbData,sizeof(BYTE),TRUE);
 303     /*TRACE("used %u\n",ptr-pSerial->pbData);*/
 304
 305     /* null1 */
 306     serialize_dword(pInfo->null1,&ptr);
 307     /*TRACE("used %u\n",ptr-pSerial->pbData);*/
 308
 309     /* hash_alg */
 310     serialize_dword(pInfo->hash_alg,&ptr);
 311     /*TRACE("used %u\n",ptr-pSerial->pbData);*/
 312     /* hash_len */
 313     serialize_dword(pInfo->hash_len,&ptr);
 314     /*TRACE("used %u\n",ptr-pSerial->pbData);*/
 315
 316     /* salt */
 317     serialize_string(pInfo->salt.pbData,&ptr,
 318                      pInfo->salt.cbData,sizeof(BYTE),TRUE);
 319     /*TRACE("used %u\n",ptr-pSerial->pbData);*/
 320
 321     /* cipher */
 322     serialize_string(pInfo->cipher.pbData,&ptr,
 323                      pInfo->cipher.cbData,sizeof(BYTE),TRUE);
 324     /*TRACE("used %u\n",ptr-pSerial->pbData);*/
 325
 326     /* fingerprint */
 327     serialize_string(pInfo->fingerprint.pbData,&ptr,
 328                      pInfo->fingerprint.cbData,sizeof(BYTE),TRUE);
 329     /*TRACE("used %u\n",ptr-pSerial->pbData);*/
 330
 331     if (ptr - pSerial->pbData != dwStruct)
 332     {
 333         ERR("struct size changed!? expected %lu\n", dwStruct);
 334         LocalFree(pSerial->pbData);
 335         pSerial->pbData=NULL;
 336         pSerial->cbData=0;
 337         return FALSE;
 338     }
 339
 340     return TRUE;
 341 }
 342
 343 static
 344 BOOL unserialize(const DATA_BLOB *pSerial, struct protect_data_t *pInfo)
 345 {
 346     BYTE * ptr;
 347     DWORD index;
 348     DWORD size;
 349     BOOL status=TRUE;
 350
 351     TRACE("called\n");
 352
 353     if (!pInfo || !pSerial || !pSerial->pbData)
 354         return FALSE;
 355
 356     index=0;
 357     ptr=pSerial->pbData;
 358     size=pSerial->cbData;
 359
 360     /* count0 */
 361     if (!unserialize_dword(ptr,&index,size,&pInfo->count0))
 362     {
 363         ERR("reading count0 failed!\n");
 364         return FALSE;
 365     }
 366
 367     /* info0 */
 368     if (!unserialize_string(ptr,&index,size,16,sizeof(BYTE),FALSE,
 369                             &pInfo->info0.pbData, &pInfo->info0.cbData))
 370     {
 371         ERR("reading info0 failed!\n");
 372         return FALSE;
 373     }
 374
 375     /* count1 */
 376     if (!unserialize_dword(ptr,&index,size,&pInfo->count1))
 377     {
 378         ERR("reading count1 failed!\n");
 379         return FALSE;
 380     }
 381
 382     /* info1 */
 383     if (!unserialize_string(ptr,&index,size,16,sizeof(BYTE),FALSE,
 384                             &pInfo->info1.pbData, &pInfo->info1.cbData))
 385     {
 386         ERR("reading info1 failed!\n");
 387         return FALSE;
 388     }
 389
 390     /* null0 */
 391     if (!unserialize_dword(ptr,&index,size,&pInfo->null0))
 392     {
 393         ERR("reading null0 failed!\n");
 394         return FALSE;
 395     }
 396
 397     /* szDataDescr */
 398     if (!unserialize_string(ptr,&index,size,0,sizeof(BYTE),TRUE,
 399                             (BYTE**)&pInfo->szDataDescr, NULL))
 400     {
 401         ERR("reading szDataDescr failed!\n");
 402         return FALSE;
 403     }
 404
 405     /* cipher_alg */
 406     if (!unserialize_dword(ptr,&index,size,(DWORD*)&pInfo->cipher_alg))
 407     {
 408         ERR("reading cipher_alg failed!\n");
 409         return FALSE;
 410     }
 411
 412     /* cipher_key_len */
 413     if (!unserialize_dword(ptr,&index,size,&pInfo->cipher_key_len))
 414     {
 415         ERR("reading cipher_key_len failed!\n");
 416         return FALSE;
 417     }
 418
 419     /* data0 */
 420     if (!unserialize_string(ptr,&index,size,0,sizeof(BYTE),TRUE,
 421                             &pInfo->data0.pbData, &pInfo->data0.cbData))
 422     {
 423         ERR("reading data0 failed!\n");
 424         return FALSE;
 425     }
 426
 427     /* null1 */
 428     if (!unserialize_dword(ptr,&index,size,&pInfo->null1))
 429     {
 430         ERR("reading null1 failed!\n");
 431         return FALSE;
 432     }
 433
 434     /* hash_alg */
 435     if (!unserialize_dword(ptr,&index,size,(DWORD*)&pInfo->hash_alg))
 436     {
 437         ERR("reading hash_alg failed!\n");
 438         return FALSE;
 439     }
 440
 441     /* hash_len */
 442     if (!unserialize_dword(ptr,&index,size,&pInfo->hash_len))
 443     {
 444         ERR("reading hash_len failed!\n");
 445         return FALSE;
 446     }
 447
 448     /* salt */
 449     if (!unserialize_string(ptr,&index,size,0,sizeof(BYTE),TRUE,
 450                             &pInfo->salt.pbData, &pInfo->salt.cbData))
 451     {
 452         ERR("reading salt failed!\n");
 453         return FALSE;
 454     }
 455
 456     /* cipher */
 457     if (!unserialize_string(ptr,&index,size,0,sizeof(BYTE),TRUE,
 458                             &pInfo->cipher.pbData, &pInfo->cipher.cbData))
 459     {
 460         ERR("reading cipher failed!\n");
 461         return FALSE;
 462     }
 463
 464     /* fingerprint */
 465     if (!unserialize_string(ptr,&index,size,0,sizeof(BYTE),TRUE,
 466                             &pInfo->fingerprint.pbData, &pInfo->fingerprint.cbData))
 467     {
 468         ERR("reading fingerprint failed!\n");
 469         return FALSE;
 470     }
 471
 472     /* allow structure size to be too big (since some applications
 473      * will pad this up to 256 bytes, it seems) */
 474     if (index>size)
 475     {
 476         /* this is an impossible-to-reach test, but if the padding
 477          * issue is ever understood, this may become more useful */
 478         ERR("loaded corrupt structure! (used %lu expected %lu)\n", index, size);
 479         status=FALSE;
 480     }
 481
 482     return status;
 483 }
 484
 485 /* perform sanity checks */
 486 static
 487 BOOL valid_protect_data(const struct protect_data_t *pInfo)
 488 {
 489     BOOL status=TRUE;
 490
 491     TRACE("called\n");
 492
 493     if (pInfo->count0 != 0x0001)
 494     {
 495         ERR("count0 != 0x0001 !\n");
 496         status=FALSE;
 497     }
 498     if (pInfo->count1 != 0x0001)
 499     {
 500         ERR("count0 != 0x0001 !\n");
 501         status=FALSE;
 502     }
 503     if (pInfo->null0 != 0x0000)
 504     {
 505         ERR("null0 != 0x0000 !\n");
 506         status=FALSE;
 507     }
 508     if (pInfo->null1 != 0x0000)
 509     {
 510         ERR("null1 != 0x0000 !\n");
 511         status=FALSE;
 512     }
 513     /* since we have no idea what info0 is used for, and it seems
 514      * rather constant, we can test for a Wine-specific magic string
 515      * there to be reasonably sure we're using data created by the Wine
 516      * implementation of CryptProtectData.
 517      */
 518     if (pInfo->info0.cbData!=strlen(crypt_magic_str)+1 ||
 519         strcmp( (LPCSTR)pInfo->info0.pbData,crypt_magic_str) != 0)
 520     {
 521         ERR("info0 magic value not matched !\n");
 522         status=FALSE;
 523     }
 524
 525     if (!status)
 526     {
 527         ERR("unrecognized CryptProtectData block\n");
 528     }
 529
 530     return status;
 531 }
 532
 533 static
 534 void free_protect_data(struct protect_data_t * pInfo)
 535 {
 536     TRACE("called\n");
 537
 538     if (!pInfo) return;
 539
 540     CryptMemFree(pInfo->info0.pbData);
 541     CryptMemFree(pInfo->info1.pbData);
 542     CryptMemFree(pInfo->szDataDescr);
 543     CryptMemFree(pInfo->data0.pbData);
 544     CryptMemFree(pInfo->salt.pbData);
 545     CryptMemFree(pInfo->cipher.pbData);
 546     CryptMemFree(pInfo->fingerprint.pbData);
 547 }
 548
 549 /* copies a string into a data blob */
 550 static
 551 BYTE *convert_str_to_blob(LPCSTR str, DATA_BLOB *blob)
 552 {
 553     if (!str || !blob) return NULL;
 554
 555     blob->cbData=strlen(str)+1;
 556     if (!(blob->pbData=CryptMemAlloc(blob->cbData)))
 557     {
 558         blob->cbData=0;
 559     }
 560     else {
 561         strcpy((LPSTR)blob->pbData, str);
 562     }
 563
 564     return blob->pbData;
 565 }
 566
 567 /*
 568  * Populates everything except "cipher" and "fingerprint".
 569  */
 570 static
 571 BOOL fill_protect_data(struct protect_data_t * pInfo, LPCWSTR szDataDescr,
 572                        HCRYPTPROV hProv)
 573 {
 574     DWORD dwStrLen;
 575
 576     TRACE("called\n");
 577
 578     if (!pInfo) return FALSE;
 579
 580     dwStrLen=lstrlenW(szDataDescr);
 581
 582     memset(pInfo,0,sizeof(*pInfo));
 583
 584     pInfo->count0=0x0001;
 585
 586     convert_str_to_blob(crypt_magic_str, &pInfo->info0);
 587
 588     pInfo->count1=0x0001;
 589
 590     convert_str_to_blob(crypt_magic_str, &pInfo->info1);
 591
 592     pInfo->null0=0x0000;
 593
 594     if ((pInfo->szDataDescr=CryptMemAlloc((dwStrLen+1)*sizeof(WCHAR))))
 595     {
 596         memcpy(pInfo->szDataDescr,szDataDescr,(dwStrLen+1)*sizeof(WCHAR));
 597     }
 598
 599     pInfo->cipher_alg=CRYPT32_PROTECTDATA_KEY_CALG;
 600     pInfo->cipher_key_len=CRYPT32_PROTECTDATA_KEY_LEN;
 601
 602     convert_str_to_blob(crypt_magic_str, &pInfo->data0);
 603
 604     pInfo->null1=0x0000;
 605     pInfo->hash_alg=CRYPT32_PROTECTDATA_HASH_CALG;
 606     pInfo->hash_len=CRYPT32_PROTECTDATA_HASH_LEN;
 607
 608     /* allocate memory to hold a salt */
 609     if ((pInfo->salt.pbData=CryptMemAlloc(CRYPT32_PROTECTDATA_SALT_LEN)))
 610     {
 611         /* generate random salt */
 612         if (!CryptGenRandom(hProv, CRYPT32_PROTECTDATA_SALT_LEN, pInfo->salt.pbData))
 613         {
 614             ERR("CryptGenRandom\n");
 615             free_protect_data(pInfo);
 616             return FALSE;
 617         }
 618         pInfo->salt.cbData=CRYPT32_PROTECTDATA_SALT_LEN;
 619         /* debug: show our salt */
 620         TRACE_DATA_BLOB(&pInfo->salt);
 621     }
 622     pInfo->cipher.cbData=0;
 623     pInfo->cipher.pbData=NULL;
 624
 625     pInfo->fingerprint.cbData=0;
 626     pInfo->fingerprint.pbData=NULL;
 627
 628     /* check all the allocations at once */
 629     if (!pInfo->info0.pbData ||
 630         !pInfo->info1.pbData ||
 631         !pInfo->szDataDescr  ||
 632         !pInfo->data0.pbData ||
 633         !pInfo->salt.pbData
 634         )
 635     {
 636         ERR("could not allocate protect_data structures\n");
 637         free_protect_data(pInfo);
 638         return FALSE;
 639     }
 640
 641     return TRUE;
 642 }
 643
 644 static
 645 BOOL convert_hash_to_blob(HCRYPTHASH hHash, DATA_BLOB * blob)
 646 {
 647     DWORD dwSize;
 648
 649     TRACE("called\n");
 650
 651     if (!blob) return FALSE;
 652
 653     dwSize=sizeof(DWORD);
 654     if (!CryptGetHashParam(hHash, HP_HASHSIZE, (BYTE*)&blob->cbData,
 655                            &dwSize, 0))
 656     {
 657         ERR("failed to get hash size\n");
 658         return FALSE;
 659     }
 660
 661     if (!(blob->pbData=CryptMemAlloc(blob->cbData)))
 662     {
 663         ERR("failed to allocate blob memory\n");
 664         return FALSE;
 665     }
 666
 667     dwSize=blob->cbData;
 668     if (!CryptGetHashParam(hHash, HP_HASHVAL, blob->pbData, &dwSize, 0))
 669     {
 670         ERR("failed to get hash value\n");
 671         CryptMemFree(blob->pbData);
 672         blob->pbData=NULL;
 673         blob->cbData=0;
 674         return FALSE;
 675     }
 676
 677     return TRUE;
 678 }
 679
 680 /* test that a given hash matches an exported-to-blob hash value */
 681 static
 682 BOOL hash_matches_blob(HCRYPTHASH hHash, const DATA_BLOB *two)
 683 {
 684     BOOL rc = FALSE;
 685     DATA_BLOB one;
 686
 687     if (!two || !two->pbData) return FALSE;
 688
 689     if (!convert_hash_to_blob(hHash,&one)) {
 690         return FALSE;
 691     }
 692
 693     if ( one.cbData == two->cbData &&
 694          memcmp( one.pbData, two->pbData, one.cbData ) == 0 )
 695     {
 696         rc = TRUE;
 697     }
 698
 699     CryptMemFree(one.pbData);
 700     return rc;
 701 }
 702
 703 /* create an encryption key from a given salt and optional entropy */
 704 static
 705 BOOL load_encryption_key(HCRYPTPROV hProv, DWORD key_len, const DATA_BLOB *salt,
 706                          const DATA_BLOB *pOptionalEntropy, HCRYPTKEY *phKey)
 707 {
 708     BOOL rc = TRUE;
 709     HCRYPTHASH hSaltHash;
 710     char * szUsername = NULL;
 711     DWORD dwUsernameLen;
 712     DWORD dwError;
 713
 714     /* create hash for salt */
 715     if (!salt || !phKey ||
 716         !CryptCreateHash(hProv,CRYPT32_PROTECTDATA_HASH_CALG,0,0,&hSaltHash))
 717     {
 718         ERR("CryptCreateHash\n");
 719         return FALSE;
 720     }
 721
 722     /* This should be the "logon credentials" instead of username */
 723     dwError=GetLastError();
 724     dwUsernameLen = 0;
 725     if (!GetUserNameA(NULL, &dwUsernameLen) &&
 726         GetLastError() == ERROR_INSUFFICIENT_BUFFER && dwUsernameLen &&
 727         (szUsername = CryptMemAlloc(dwUsernameLen)))
 728     {
 729         szUsername[0]='\0';
 730         GetUserNameA( szUsername, &dwUsernameLen );
 731     }
 732     SetLastError(dwError);
 733
 734     /* salt the hash with:
 735      * - the user id
 736      * - an "internal secret"
 737      * - randomness (from the salt)
 738      * - user-supplied entropy
 739      */
 740     if ((szUsername && !CryptHashData(hSaltHash,(LPBYTE)szUsername,dwUsernameLen,0)) ||
 741         !CryptHashData(hSaltHash,crypt32_protectdata_secret,
 742                                  sizeof(crypt32_protectdata_secret)-1,0) ||
 743         !CryptHashData(hSaltHash,salt->pbData,salt->cbData,0) ||
 744         (pOptionalEntropy && !CryptHashData(hSaltHash,
 745                                             pOptionalEntropy->pbData,
 746                                             pOptionalEntropy->cbData,0)))
 747     {
 748         ERR("CryptHashData\n");
 749         rc = FALSE;
 750     }
 751
 752     /* produce a symmetric key */
 753     if (rc && !CryptDeriveKey(hProv,CRYPT32_PROTECTDATA_KEY_CALG,
 754                               hSaltHash,key_len << 16 | CRYPT_EXPORTABLE,phKey))
 755     {
 756         ERR("CryptDeriveKey\n");
 757         rc = FALSE;
 758     }
 759
 760     /* clean up */
 761     CryptDestroyHash(hSaltHash);
 762     CryptMemFree(szUsername);
 763
 764     return rc;
 765 }
 766
 767 /* debugging tool to print the structures of a ProtectData call */
 768 static void
 769 report(const DATA_BLOB* pDataIn, const DATA_BLOB* pOptionalEntropy,
 770        CRYPTPROTECT_PROMPTSTRUCT* pPromptStruct, DWORD dwFlags)
 771 {
 772     TRACE("pPromptStruct: %p\n", pPromptStruct);
 773     if (pPromptStruct)
 774     {
 775         TRACE("  cbSize: 0x%lx\n", pPromptStruct->cbSize);
 776         TRACE("  dwPromptFlags: 0x%lx\n", pPromptStruct->dwPromptFlags);
 777         TRACE("  hwndApp: %p\n", pPromptStruct->hwndApp);
 778         TRACE("  szPrompt: %p %s\n",
 779               pPromptStruct->szPrompt,
 780               pPromptStruct->szPrompt ? debugstr_w(pPromptStruct->szPrompt)
 781               : "");
 782     }
 783     TRACE("dwFlags: 0x%04lx\n", dwFlags);
 784     TRACE_DATA_BLOB(pDataIn);
 785     if (pOptionalEntropy)
 786     {
 787         TRACE_DATA_BLOB(pOptionalEntropy);
 788         TRACE("  %s\n",debugstr_an((LPCSTR)pOptionalEntropy->pbData,pOptionalEntropy->cbData));
 789     }
 790
 791 }
 792
 793
 794 /***************************************************************************
 795  * CryptProtectData     [CRYPT32.@]
 796  *
 797  * Generate Cipher data from given Plain and Entropy data.
 798  *
 799  * PARAMS
 800  *  pDataIn          [I] Plain data to be enciphered
 801  *  szDataDescr      [I] Optional Unicode string describing the Plain data
 802  *  pOptionalEntropy [I] Optional entropy data to adjust cipher, can be NULL
 803  *  pvReserved       [I] Reserved, must be NULL
 804  *  pPromptStruct    [I] Structure describing if/how to prompt during ciphering
 805  *  dwFlags          [I] Flags describing options to the ciphering
 806  *  pDataOut         [O] Resulting Cipher data, for calls to CryptUnprotectData
 807  *
 808  * RETURNS
 809  *  TRUE  If a Cipher was generated.
 810  *  FALSE If something failed and no Cipher is available.
 811  *
 812  * FIXME
 813  *  The true Windows encryption and keying mechanisms are unknown.
 814  *
 815  *  dwFlags and pPromptStruct are currently ignored.
 816  *
 817  * NOTES
 818  *  Memory allocated in pDataOut must be freed with LocalFree.
 819  *
 820  */
 821 BOOL WINAPI CryptProtectData(DATA_BLOB* pDataIn,
 822                              LPCWSTR szDataDescr,
 823                              DATA_BLOB* pOptionalEntropy,
 824                              PVOID pvReserved,
 825                              CRYPTPROTECT_PROMPTSTRUCT* pPromptStruct,
 826                              DWORD dwFlags,
 827                              DATA_BLOB* pDataOut)
 828 {
 829     BOOL rc = FALSE;
 830     HCRYPTPROV hProv;
 831     struct protect_data_t protect_data;
 832     HCRYPTHASH hHash;
 833     HCRYPTKEY hKey;
 834     DWORD dwLength;
 835
 836     TRACE("called\n");
 837
 838     SetLastError(ERROR_SUCCESS);
 839
 840     if (!pDataIn || !pDataOut)
 841     {
 842         SetLastError(ERROR_INVALID_PARAMETER);
 843         goto finished;
 844     }
 845
 846     /* debug: show our arguments */
 847     report(pDataIn,pOptionalEntropy,pPromptStruct,dwFlags);
 848     TRACE("\tszDataDescr: %p %s\n", szDataDescr,
 849           szDataDescr ? debugstr_w(szDataDescr) : "");
 850
 851     /* Windows appears to create an empty szDataDescr instead of maintaining
 852      * a NULL */
 853     if (!szDataDescr)
 854         szDataDescr = L"";
 855
 856     /* get crypt context */
 857     if (!CryptAcquireContextW(&hProv,NULL,MS_ENHANCED_PROV_W,CRYPT32_PROTECTDATA_PROV,CRYPT_VERIFYCONTEXT))
 858     {
 859         ERR("CryptAcquireContextW failed\n");
 860         goto finished;
 861     }
 862
 863     /* populate our structure */
 864     if (!fill_protect_data(&protect_data,szDataDescr,hProv))
 865     {
 866         ERR("fill_protect_data\n");
 867         goto free_context;
 868     }
 869
 870     /* load key */
 871     if (!load_encryption_key(hProv,protect_data.cipher_key_len,&protect_data.salt,pOptionalEntropy,&hKey))
 872     {
 873         goto free_protect_data;
 874     }
 875
 876     /* create a hash for the encryption validation */
 877     if (!CryptCreateHash(hProv,CRYPT32_PROTECTDATA_HASH_CALG,0,0,&hHash))
 878     {
 879         ERR("CryptCreateHash\n");
 880         goto free_key;
 881     }
 882
 883     /* calculate storage required */
 884     dwLength=pDataIn->cbData;
 885     if (CryptEncrypt(hKey, 0, TRUE, 0, pDataIn->pbData, &dwLength, 0) ||
 886         GetLastError()!=ERROR_MORE_DATA)
 887     {
 888         ERR("CryptEncrypt\n");
 889         goto free_hash;
 890     }
 891     TRACE("required encrypted storage: %lu\n", dwLength);
 892
 893     /* copy plain text into cipher area for CryptEncrypt call */
 894     protect_data.cipher.cbData=dwLength;
 895     if (!(protect_data.cipher.pbData=CryptMemAlloc(
 896                                                 protect_data.cipher.cbData)))
 897     {
 898         ERR("CryptMemAlloc\n");
 899         goto free_hash;
 900     }
 901     memcpy(protect_data.cipher.pbData,pDataIn->pbData,pDataIn->cbData);
 902
 903     /* encrypt! */
 904     dwLength=pDataIn->cbData;
 905     if (!CryptEncrypt(hKey, hHash, TRUE, 0, protect_data.cipher.pbData,
 906                       &dwLength, protect_data.cipher.cbData))
 907     {
 908         ERR("CryptEncrypt %lu\n", GetLastError());
 909         goto free_hash;
 910     }
 911     protect_data.cipher.cbData=dwLength;
 912
 913     /* debug: show the cipher */
 914     TRACE_DATA_BLOB(&protect_data.cipher);
 915
 916     /* attach our fingerprint */
 917     if (!convert_hash_to_blob(hHash, &protect_data.fingerprint))
 918     {
 919         ERR("convert_hash_to_blob\n");
 920         goto free_hash;
 921     }
 922
 923     /* serialize into an opaque blob */
 924     if (!serialize(&protect_data, pDataOut))
 925     {
 926         ERR("serialize\n");
 927         goto free_hash;
 928     }
 929
 930     /* success! */
 931     rc=TRUE;
 932
 933 free_hash:
 934     CryptDestroyHash(hHash);
 935 free_key:
 936     CryptDestroyKey(hKey);
 937 free_protect_data:
 938     free_protect_data(&protect_data);
 939 free_context:
 940     CryptReleaseContext(hProv,0);
 941 finished:
 942     /* If some error occurred, and no error code was set, force one. */
 943     if (!rc && GetLastError()==ERROR_SUCCESS)
 944     {
 945         SetLastError(ERROR_INVALID_DATA);
 946     }
 947
 948     if (rc)
 949     {
 950         SetLastError(ERROR_SUCCESS);
 951
 952         TRACE_DATA_BLOB(pDataOut);
 953     }
 954
 955     TRACE("returning %s\n", rc ? "ok" : "FAIL");
 956
 957     return rc;
 958 }
 959
 960
 961 /***************************************************************************
 962  * CryptUnprotectData   [CRYPT32.@]
 963  *
 964  * Generate Plain data and Description from given Cipher and Entropy data.
 965  *
 966  * PARAMS
 967  *  pDataIn          [I] Cipher data to be decoded
 968  *  ppszDataDescr    [O] Optional Unicode string describing the Plain data
 969  *  pOptionalEntropy [I] Optional entropy data to adjust cipher, can be NULL
 970  *  pvReserved       [I] Reserved, must be NULL
 971  *  pPromptStruct    [I] Structure describing if/how to prompt during decoding
 972  *  dwFlags          [I] Flags describing options to the decoding
 973  *  pDataOut         [O] Resulting Plain data, from calls to CryptProtectData
 974  *
 975  * RETURNS
 976  *  TRUE  If a Plain was generated.
 977  *  FALSE If something failed and no Plain is available.
 978  *
 979  * FIXME
 980  *  The true Windows encryption and keying mechanisms are unknown.
 981  *
 982  *  dwFlags and pPromptStruct are currently ignored.
 983  *
 984  * NOTES
 985  *  Memory allocated in pDataOut and non-NULL ppszDataDescr must be freed
 986  *  with LocalFree.
 987  *
 988  */
 989 BOOL WINAPI CryptUnprotectData(DATA_BLOB* pDataIn,
 990                                LPWSTR * ppszDataDescr,
 991                                DATA_BLOB* pOptionalEntropy,
 992                                PVOID pvReserved,
 993                                CRYPTPROTECT_PROMPTSTRUCT* pPromptStruct,
 994                                DWORD dwFlags,
 995                                DATA_BLOB* pDataOut)
 996 {
 997     BOOL rc = FALSE;
 998
 999     HCRYPTPROV hProv;
1000     struct protect_data_t protect_data;
1001     HCRYPTHASH hHash;
1002     HCRYPTKEY hKey;
1003     DWORD dwLength;
1004
1005     const char * announce_bad_opaque_data = "CryptUnprotectData received a DATA_BLOB that seems to have NOT been generated by Wine.  Please enable tracing ('export WINEDEBUG=crypt') to see details.";
1006
1007     TRACE("called\n");
1008
1009     SetLastError(ERROR_SUCCESS);
1010
1011     if (!pDataIn || !pDataOut)
1012     {
1013         SetLastError(ERROR_INVALID_PARAMETER);
1014         goto finished;
1015     }
1016     if (!pDataIn->cbData)
1017     {
1018         SetLastError(ERROR_INVALID_DATA);
1019         goto finished;
1020     }
1021
1022     /* debug: show our arguments */
1023     report(pDataIn,pOptionalEntropy,pPromptStruct,dwFlags);
1024     TRACE("\tppszDataDescr: %p\n", ppszDataDescr);
1025
1026     /* take apart the opaque blob */
1027     if (!unserialize(pDataIn, &protect_data))
1028     {
1029         SetLastError(ERROR_INVALID_DATA);
1030         FIXME("%s\n",announce_bad_opaque_data);
1031         goto finished;
1032     }
1033
1034     /* perform basic validation on the resulting structure */
1035     if (!valid_protect_data(&protect_data))
1036     {
1037         SetLastError(ERROR_INVALID_DATA);
1038         FIXME("%s\n",announce_bad_opaque_data);
1039         goto free_protect_data;
1040     }
1041
1042     /* get a crypt context */
1043     if (!CryptAcquireContextW(&hProv,NULL,MS_ENHANCED_PROV_W,CRYPT32_PROTECTDATA_PROV,CRYPT_VERIFYCONTEXT))
1044     {
1045         ERR("CryptAcquireContextW failed\n");
1046         goto free_protect_data;
1047     }
1048
1049     /* load key */
1050     if (!load_encryption_key(hProv,protect_data.cipher_key_len,&protect_data.salt,pOptionalEntropy,&hKey))
1051     {
1052         goto free_context;
1053     }
1054
1055     /* create a hash for the decryption validation */
1056     if (!CryptCreateHash(hProv,CRYPT32_PROTECTDATA_HASH_CALG,0,0,&hHash))
1057     {
1058         ERR("CryptCreateHash\n");
1059         goto free_key;
1060     }
1061
1062     /* prepare for plaintext */
1063     pDataOut->cbData=protect_data.cipher.cbData;
1064     if (!(pDataOut->pbData=LocalAlloc( LPTR, pDataOut->cbData)))
1065     {
1066         ERR("CryptMemAlloc\n");
1067         goto free_hash;
1068     }
1069     memcpy(pDataOut->pbData,protect_data.cipher.pbData,protect_data.cipher.cbData);
1070
1071     /* decrypt! */
1072     if (!CryptDecrypt(hKey, hHash, TRUE, 0, pDataOut->pbData,
1073                       &pDataOut->cbData) ||
1074         /* check the hash fingerprint */
1075         pDataOut->cbData > protect_data.cipher.cbData ||
1076         !hash_matches_blob(hHash, &protect_data.fingerprint))
1077     {
1078         SetLastError(ERROR_INVALID_DATA);
1079
1080         LocalFree( pDataOut->pbData );
1081         pDataOut->pbData = NULL;
1082         pDataOut->cbData = 0;
1083
1084         goto free_hash;
1085     }
1086
1087     /* Copy out the description */
1088     dwLength = (lstrlenW(protect_data.szDataDescr)+1) * sizeof(WCHAR);
1089     if (ppszDataDescr)
1090     {
1091         if (!(*ppszDataDescr = LocalAlloc(LPTR,dwLength)))
1092         {
1093             ERR("LocalAlloc (ppszDataDescr)\n");
1094             goto free_hash;
1095         }
1096         else {
1097             memcpy(*ppszDataDescr,protect_data.szDataDescr,dwLength);
1098         }
1099     }
1100
1101     /* success! */
1102     rc = TRUE;
1103
1104 free_hash:
1105     CryptDestroyHash(hHash);
1106 free_key:
1107     CryptDestroyKey(hKey);
1108 free_context:
1109     CryptReleaseContext(hProv,0);
1110 free_protect_data:
1111     free_protect_data(&protect_data);
1112 finished:
1113     /* If some error occurred, and no error code was set, force one. */
1114     if (!rc && GetLastError()==ERROR_SUCCESS)
1115     {
1116         SetLastError(ERROR_INVALID_DATA);
1117     }
1118
1119     if (rc) {
1120         SetLastError(ERROR_SUCCESS);
1121
1122         if (ppszDataDescr)
1123         {
1124             TRACE("szDataDescr: %s\n",debugstr_w(*ppszDataDescr));
1125         }
1126         TRACE_DATA_BLOB(pDataOut);
1127     }
1128
1129     TRACE("returning %s\n", rc ? "ok" : "FAIL");
1130
1131     return rc;
1132 }