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!? %u != expected %u\n",
 334             ptr - pSerial->pbData, dwStruct);
 335         LocalFree(pSerial->pbData);
 336         pSerial->pbData=NULL;
 337         pSerial->cbData=0;
 338         return FALSE;
 339     }
 340
 341     return TRUE;
 342 }
 343
 344 static
 345 BOOL unserialize(const DATA_BLOB *pSerial, struct protect_data_t *pInfo)
 346 {
 347     BYTE * ptr;
 348     DWORD index;
 349     DWORD size;
 350     BOOL status=TRUE;
 351
 352     TRACE("called\n");
 353
 354     if (!pInfo || !pSerial || !pSerial->pbData)
 355         return FALSE;
 356
 357     index=0;
 358     ptr=pSerial->pbData;
 359     size=pSerial->cbData;
 360
 361     /* count0 */
 362     if (!unserialize_dword(ptr,&index,size,&pInfo->count0))
 363     {
 364         ERR("reading count0 failed!\n");
 365         return FALSE;
 366     }
 367
 368     /* info0 */
 369     if (!unserialize_string(ptr,&index,size,16,sizeof(BYTE),FALSE,
 370                             &pInfo->info0.pbData, &pInfo->info0.cbData))
 371     {
 372         ERR("reading info0 failed!\n");
 373         return FALSE;
 374     }
 375
 376     /* count1 */
 377     if (!unserialize_dword(ptr,&index,size,&pInfo->count1))
 378     {
 379         ERR("reading count1 failed!\n");
 380         return FALSE;
 381     }
 382
 383     /* info1 */
 384     if (!unserialize_string(ptr,&index,size,16,sizeof(BYTE),FALSE,
 385                             &pInfo->info1.pbData, &pInfo->info1.cbData))
 386     {
 387         ERR("reading info1 failed!\n");
 388         return FALSE;
 389     }
 390
 391     /* null0 */
 392     if (!unserialize_dword(ptr,&index,size,&pInfo->null0))
 393     {
 394         ERR("reading null0 failed!\n");
 395         return FALSE;
 396     }
 397
 398     /* szDataDescr */
 399     if (!unserialize_string(ptr,&index,size,0,sizeof(BYTE),TRUE,
 400                             (BYTE**)&pInfo->szDataDescr, NULL))
 401     {
 402         ERR("reading szDataDescr failed!\n");
 403         return FALSE;
 404     }
 405
 406     /* cipher_alg */
 407     if (!unserialize_dword(ptr,&index,size,&pInfo->cipher_alg))
 408     {
 409         ERR("reading cipher_alg failed!\n");
 410         return FALSE;
 411     }
 412
 413     /* cipher_key_len */
 414     if (!unserialize_dword(ptr,&index,size,&pInfo->cipher_key_len))
 415     {
 416         ERR("reading cipher_key_len failed!\n");
 417         return FALSE;
 418     }
 419
 420     /* data0 */
 421     if (!unserialize_string(ptr,&index,size,0,sizeof(BYTE),TRUE,
 422                             &pInfo->data0.pbData, &pInfo->data0.cbData))
 423     {
 424         ERR("reading data0 failed!\n");
 425         return FALSE;
 426     }
 427
 428     /* null1 */
 429     if (!unserialize_dword(ptr,&index,size,&pInfo->null1))
 430     {
 431         ERR("reading null1 failed!\n");
 432         return FALSE;
 433     }
 434
 435     /* hash_alg */
 436     if (!unserialize_dword(ptr,&index,size,&pInfo->hash_alg))
 437     {
 438         ERR("reading hash_alg failed!\n");
 439         return FALSE;
 440     }
 441
 442     /* hash_len */
 443     if (!unserialize_dword(ptr,&index,size,&pInfo->hash_len))
 444     {
 445         ERR("reading hash_len failed!\n");
 446         return FALSE;
 447     }
 448
 449     /* salt */
 450     if (!unserialize_string(ptr,&index,size,0,sizeof(BYTE),TRUE,
 451                             &pInfo->salt.pbData, &pInfo->salt.cbData))
 452     {
 453         ERR("reading salt failed!\n");
 454         return FALSE;
 455     }
 456
 457     /* cipher */
 458     if (!unserialize_string(ptr,&index,size,0,sizeof(BYTE),TRUE,
 459                             &pInfo->cipher.pbData, &pInfo->cipher.cbData))
 460     {
 461         ERR("reading cipher failed!\n");
 462         return FALSE;
 463     }
 464
 465     /* fingerprint */
 466     if (!unserialize_string(ptr,&index,size,0,sizeof(BYTE),TRUE,
 467                             &pInfo->fingerprint.pbData, &pInfo->fingerprint.cbData))
 468     {
 469         ERR("reading fingerprint failed!\n");
 470         return FALSE;
 471     }
 472
 473     /* allow structure size to be too big (since some applications
 474      * will pad this up to 256 bytes, it seems) */
 475     if (index>size)
 476     {
 477         /* this is an impossible-to-reach test, but if the padding
 478          * issue is ever understood, this may become more useful */
 479         ERR("loaded corrupt structure! (used %u expected %u)\n", index, size);
 480         status=FALSE;
 481     }
 482
 483     return status;
 484 }
 485
 486 /* perform sanity checks */
 487 static
 488 BOOL valid_protect_data(const struct protect_data_t *pInfo)
 489 {
 490     BOOL status=TRUE;
 491
 492     TRACE("called\n");
 493
 494     if (pInfo->count0 != 0x0001)
 495     {
 496         ERR("count0 != 0x0001 !\n");
 497         status=FALSE;
 498     }
 499     if (pInfo->count1 != 0x0001)
 500     {
 501         ERR("count0 != 0x0001 !\n");
 502         status=FALSE;
 503     }
 504     if (pInfo->null0 != 0x0000)
 505     {
 506         ERR("null0 != 0x0000 !\n");
 507         status=FALSE;
 508     }
 509     if (pInfo->null1 != 0x0000)
 510     {
 511         ERR("null1 != 0x0000 !\n");
 512         status=FALSE;
 513     }
 514     /* since we have no idea what info0 is used for, and it seems
 515      * rather constant, we can test for a Wine-specific magic string
 516      * there to be reasonably sure we're using data created by the Wine
 517      * implementation of CryptProtectData.
 518      */
 519     if (pInfo->info0.cbData!=strlen(crypt_magic_str)+1 ||
 520         strcmp( (LPCSTR)pInfo->info0.pbData,crypt_magic_str) != 0)
 521     {
 522         ERR("info0 magic value not matched !\n");
 523         status=FALSE;
 524     }
 525
 526     if (!status)
 527     {
 528         ERR("unrecognized CryptProtectData block\n");
 529     }
 530
 531     return status;
 532 }
 533
 534 static
 535 void free_protect_data(struct protect_data_t * pInfo)
 536 {
 537     TRACE("called\n");
 538
 539     if (!pInfo) return;
 540
 541     CryptMemFree(pInfo->info0.pbData);
 542     CryptMemFree(pInfo->info1.pbData);
 543     CryptMemFree(pInfo->szDataDescr);
 544     CryptMemFree(pInfo->data0.pbData);
 545     CryptMemFree(pInfo->salt.pbData);
 546     CryptMemFree(pInfo->cipher.pbData);
 547     CryptMemFree(pInfo->fingerprint.pbData);
 548 }
 549
 550 /* copies a string into a data blob */
 551 static
 552 BYTE *convert_str_to_blob(LPCSTR str, DATA_BLOB *blob)
 553 {
 554     if (!str || !blob) return NULL;
 555
 556     blob->cbData=strlen(str)+1;
 557     if (!(blob->pbData=CryptMemAlloc(blob->cbData)))
 558     {
 559         blob->cbData=0;
 560     }
 561     else {
 562         strcpy((LPSTR)blob->pbData, str);
 563     }
 564
 565     return blob->pbData;
 566 }
 567
 568 /*
 569  * Populates everything except "cipher" and "fingerprint".
 570  */
 571 static
 572 BOOL fill_protect_data(struct protect_data_t * pInfo, LPCWSTR szDataDescr,
 573                        HCRYPTPROV hProv)
 574 {
 575     DWORD dwStrLen;
 576
 577     TRACE("called\n");
 578
 579     if (!pInfo) return FALSE;
 580
 581     dwStrLen=lstrlenW(szDataDescr);
 582
 583     memset(pInfo,0,sizeof(*pInfo));
 584
 585     pInfo->count0=0x0001;
 586
 587     convert_str_to_blob(crypt_magic_str, &pInfo->info0);
 588
 589     pInfo->count1=0x0001;
 590
 591     convert_str_to_blob(crypt_magic_str, &pInfo->info1);
 592
 593     pInfo->null0=0x0000;
 594
 595     if ((pInfo->szDataDescr=CryptMemAlloc((dwStrLen+1)*sizeof(WCHAR))))
 596     {
 597         memcpy(pInfo->szDataDescr,szDataDescr,(dwStrLen+1)*sizeof(WCHAR));
 598     }
 599
 600     pInfo->cipher_alg=CRYPT32_PROTECTDATA_KEY_CALG;
 601     pInfo->cipher_key_len=CRYPT32_PROTECTDATA_KEY_LEN;
 602
 603     convert_str_to_blob(crypt_magic_str, &pInfo->data0);
 604
 605     pInfo->null1=0x0000;
 606     pInfo->hash_alg=CRYPT32_PROTECTDATA_HASH_CALG;
 607     pInfo->hash_len=CRYPT32_PROTECTDATA_HASH_LEN;
 608
 609     /* allocate memory to hold a salt */
 610     if ((pInfo->salt.pbData=CryptMemAlloc(CRYPT32_PROTECTDATA_SALT_LEN)))
 611     {
 612         /* generate random salt */
 613         if (!CryptGenRandom(hProv, pInfo->salt.cbData, pInfo->salt.pbData))
 614         {
 615             ERR("CryptGenRandom\n");
 616             free_protect_data(pInfo);
 617             return FALSE;
 618         }
 619         pInfo->salt.cbData=CRYPT32_PROTECTDATA_SALT_LEN;
 620     }
 621
 622     /* debug: show our salt */
 623     TRACE_DATA_BLOB(&pInfo->salt);
 624
 625     pInfo->cipher.cbData=0;
 626     pInfo->cipher.pbData=NULL;
 627
 628     pInfo->fingerprint.cbData=0;
 629     pInfo->fingerprint.pbData=NULL;
 630
 631     /* check all the allocations at once */
 632     if (!pInfo->info0.pbData ||
 633         !pInfo->info1.pbData ||
 634         !pInfo->szDataDescr  ||
 635         !pInfo->data0.pbData ||
 636         !pInfo->salt.pbData
 637         )
 638     {
 639         ERR("could not allocate protect_data structures\n");
 640         free_protect_data(pInfo);
 641         return FALSE;
 642     }
 643
 644     return TRUE;
 645 }
 646
 647 static
 648 BOOL convert_hash_to_blob(HCRYPTHASH hHash, DATA_BLOB * blob)
 649 {
 650     DWORD dwSize;
 651
 652     TRACE("called\n");
 653
 654     if (!blob) return FALSE;
 655
 656     dwSize=sizeof(DWORD);
 657     if (!CryptGetHashParam(hHash, HP_HASHSIZE, (BYTE*)&blob->cbData,
 658                            &dwSize, 0))
 659     {
 660         ERR("failed to get hash size\n");
 661         return FALSE;
 662     }
 663
 664     if (!(blob->pbData=CryptMemAlloc(blob->cbData)))
 665     {
 666         ERR("failed to allocate blob memory\n");
 667         return FALSE;
 668     }
 669
 670     dwSize=blob->cbData;
 671     if (!CryptGetHashParam(hHash, HP_HASHVAL, blob->pbData, &dwSize, 0))
 672     {
 673         ERR("failed to get hash value\n");
 674         CryptMemFree(blob->pbData);
 675         blob->pbData=NULL;
 676         blob->cbData=0;
 677         return FALSE;
 678     }
 679
 680     return TRUE;
 681 }
 682
 683 /* test that a given hash matches an exported-to-blob hash value */
 684 static
 685 BOOL hash_matches_blob(HCRYPTHASH hHash, const DATA_BLOB *two)
 686 {
 687     BOOL rc = FALSE;
 688     DATA_BLOB one;
 689
 690     if (!two || !two->pbData) return FALSE;
 691
 692     if (!convert_hash_to_blob(hHash,&one)) {
 693         return FALSE;
 694     }
 695
 696     if ( one.cbData == two->cbData &&
 697          memcmp( one.pbData, two->pbData, one.cbData ) == 0 )
 698     {
 699         rc = TRUE;
 700     }
 701
 702     CryptMemFree(one.pbData);
 703     return rc;
 704 }
 705
 706 /* create an encryption key from a given salt and optional entropy */
 707 static
 708 BOOL load_encryption_key(HCRYPTPROV hProv, DWORD key_len, const DATA_BLOB *salt,
 709                          const DATA_BLOB *pOptionalEntropy, HCRYPTKEY *phKey)
 710 {
 711     BOOL rc = TRUE;
 712     HCRYPTHASH hSaltHash;
 713     char * szUsername = NULL;
 714     DWORD dwUsernameLen;
 715     DWORD dwError;
 716
 717     /* create hash for salt */
 718     if (!salt || !phKey ||
 719         !CryptCreateHash(hProv,CRYPT32_PROTECTDATA_HASH_CALG,0,0,&hSaltHash))
 720     {
 721         ERR("CryptCreateHash\n");
 722         return FALSE;
 723     }
 724
 725     /* This should be the "logon credentials" instead of username */
 726     dwError=GetLastError();
 727     dwUsernameLen = 0;
 728     if (!GetUserNameA(NULL,&dwUsernameLen) &&
 729         GetLastError()==ERROR_MORE_DATA && dwUsernameLen &&
 730         (szUsername = CryptMemAlloc(dwUsernameLen)))
 731     {
 732         szUsername[0]='\0';
 733         GetUserNameA( szUsername, &dwUsernameLen );
 734     }
 735     SetLastError(dwError);
 736
 737     /* salt the hash with:
 738      * - the user id
 739      * - an "internal secret"
 740      * - randomness (from the salt)
 741      * - user-supplied entropy
 742      */
 743     if ((szUsername && !CryptHashData(hSaltHash,(LPBYTE)szUsername,dwUsernameLen,0)) ||
 744         !CryptHashData(hSaltHash,crypt32_protectdata_secret,
 745                                  sizeof(crypt32_protectdata_secret)-1,0) ||
 746         !CryptHashData(hSaltHash,salt->pbData,salt->cbData,0) ||
 747         (pOptionalEntropy && !CryptHashData(hSaltHash,
 748                                             pOptionalEntropy->pbData,
 749                                             pOptionalEntropy->cbData,0)))
 750     {
 751         ERR("CryptHashData\n");
 752         rc = FALSE;
 753     }
 754
 755     /* produce a symmetric key */
 756     if (rc && !CryptDeriveKey(hProv,CRYPT32_PROTECTDATA_KEY_CALG,
 757                               hSaltHash,key_len << 16 | CRYPT_EXPORTABLE,phKey))
 758     {
 759         ERR("CryptDeriveKey\n");
 760         rc = FALSE;
 761     }
 762
 763     /* clean up */
 764     CryptDestroyHash(hSaltHash);
 765     CryptMemFree(szUsername);
 766
 767     return rc;
 768 }
 769
 770 /* debugging tool to print the structures of a ProtectData call */
 771 static void
 772 report(const DATA_BLOB* pDataIn, const DATA_BLOB* pOptionalEntropy,
 773        CRYPTPROTECT_PROMPTSTRUCT* pPromptStruct, DWORD dwFlags)
 774 {
 775     TRACE("pPromptStruct: %p\n", pPromptStruct);
 776     if (pPromptStruct)
 777     {
 778         TRACE("  cbSize: 0x%x\n", pPromptStruct->cbSize);
 779         TRACE("  dwPromptFlags: 0x%x\n", pPromptStruct->dwPromptFlags);
 780         TRACE("  hwndApp: %p\n", pPromptStruct->hwndApp);
 781         TRACE("  szPrompt: %p %s\n",
 782               pPromptStruct->szPrompt,
 783               pPromptStruct->szPrompt ? debugstr_w(pPromptStruct->szPrompt)
 784               : "");
 785     }
 786     TRACE("dwFlags: 0x%04x\n", dwFlags);
 787     TRACE_DATA_BLOB(pDataIn);
 788     if (pOptionalEntropy)
 789     {
 790         TRACE_DATA_BLOB(pOptionalEntropy);
 791         TRACE("  %s\n",debugstr_an((LPCSTR)pOptionalEntropy->pbData,pOptionalEntropy->cbData));
 792     }
 793
 794 }
 795
 796
 797 /***************************************************************************
 798  * CryptProtectData     [CRYPT32.@]
 799  *
 800  * Generate Cipher data from given Plain and Entropy data.
 801  *
 802  * PARAMS
 803  *  pDataIn          [I] Plain data to be enciphered
 804  *  szDataDescr      [I] Optional Unicode string describing the Plain data
 805  *  pOptionalEntropy [I] Optional entropy data to adjust cipher, can be NULL
 806  *  pvReserved       [I] Reserved, must be NULL
 807  *  pPromptStruct    [I] Structure describing if/how to prompt during ciphering
 808  *  dwFlags          [I] Flags describing options to the ciphering
 809  *  pDataOut         [O] Resulting Cipher data, for calls to CryptUnprotectData
 810  *
 811  * RETURNS
 812  *  TRUE  If a Cipher was generated.
 813  *  FALSE If something failed and no Cipher is available.
 814  *
 815  * FIXME
 816  *  The true Windows encryption and keying mechanisms are unknown.
 817  *
 818  *  dwFlags and pPromptStruct are currently ignored.
 819  *
 820  * NOTES
 821  *  Memory allocated in pDataOut must be freed with LocalFree.
 822  *
 823  */
 824 BOOL WINAPI CryptProtectData(DATA_BLOB* pDataIn,
 825                              LPCWSTR szDataDescr,
 826                              DATA_BLOB* pOptionalEntropy,
 827                              PVOID pvReserved,
 828                              CRYPTPROTECT_PROMPTSTRUCT* pPromptStruct,
 829                              DWORD dwFlags,
 830                              DATA_BLOB* pDataOut)
 831 {
 832     static const WCHAR empty_str[1];
 833     BOOL rc = FALSE;
 834     HCRYPTPROV hProv;
 835     struct protect_data_t protect_data;
 836     HCRYPTHASH hHash;
 837     HCRYPTKEY hKey;
 838     DWORD dwLength;
 839
 840     TRACE("called\n");
 841
 842     SetLastError(ERROR_SUCCESS);
 843
 844     if (!pDataIn || !pDataOut)
 845     {
 846         SetLastError(ERROR_INVALID_PARAMETER);
 847         goto finished;
 848     }
 849
 850     /* debug: show our arguments */
 851     report(pDataIn,pOptionalEntropy,pPromptStruct,dwFlags);
 852     TRACE("\tszDataDescr: %p %s\n", szDataDescr,
 853           szDataDescr ? debugstr_w(szDataDescr) : "");
 854
 855     /* Windows appears to create an empty szDataDescr instead of maintaining
 856      * a NULL */
 857     if (!szDataDescr)
 858         szDataDescr = empty_str;
 859
 860     /* get crypt context */
 861     if (!CryptAcquireContextW(&hProv,NULL,MS_ENHANCED_PROV_W,CRYPT32_PROTECTDATA_PROV,CRYPT_VERIFYCONTEXT))
 862     {
 863         ERR("CryptAcquireContextW failed\n");
 864         goto finished;
 865     }
 866
 867     /* populate our structure */
 868     if (!fill_protect_data(&protect_data,szDataDescr,hProv))
 869     {
 870         ERR("fill_protect_data\n");
 871         goto free_context;
 872     }
 873
 874     /* load key */
 875     if (!load_encryption_key(hProv,protect_data.cipher_key_len,&protect_data.salt,pOptionalEntropy,&hKey))
 876     {
 877         goto free_protect_data;
 878     }
 879
 880     /* create a hash for the encryption validation */
 881     if (!CryptCreateHash(hProv,CRYPT32_PROTECTDATA_HASH_CALG,0,0,&hHash))
 882     {
 883         ERR("CryptCreateHash\n");
 884         goto free_key;
 885     }
 886
 887     /* calculate storage required */
 888     dwLength=pDataIn->cbData;
 889     if (CryptEncrypt(hKey, 0, TRUE, 0, pDataIn->pbData, &dwLength, 0) ||
 890         GetLastError()!=ERROR_MORE_DATA)
 891     {
 892         ERR("CryptEncrypt\n");
 893         goto free_hash;
 894     }
 895     TRACE("required encrypted storage: %u\n", dwLength);
 896
 897     /* copy plain text into cipher area for CryptEncrypt call */
 898     protect_data.cipher.cbData=dwLength;
 899     if (!(protect_data.cipher.pbData=CryptMemAlloc(
 900                                                 protect_data.cipher.cbData)))
 901     {
 902         ERR("CryptMemAlloc\n");
 903         goto free_hash;
 904     }
 905     memcpy(protect_data.cipher.pbData,pDataIn->pbData,pDataIn->cbData);
 906
 907     /* encrypt! */
 908     dwLength=pDataIn->cbData;
 909     if (!CryptEncrypt(hKey, hHash, TRUE, 0, protect_data.cipher.pbData,
 910                       &dwLength, protect_data.cipher.cbData))
 911     {
 912         ERR("CryptEncrypt %u\n", GetLastError());
 913         goto free_hash;
 914     }
 915     protect_data.cipher.cbData=dwLength;
 916
 917     /* debug: show the cipher */
 918     TRACE_DATA_BLOB(&protect_data.cipher);
 919
 920     /* attach our fingerprint */
 921     if (!convert_hash_to_blob(hHash, &protect_data.fingerprint))
 922     {
 923         ERR("convert_hash_to_blob\n");
 924         goto free_hash;
 925     }
 926
 927     /* serialize into an opaque blob */
 928     if (!serialize(&protect_data, pDataOut))
 929     {
 930         ERR("serialize\n");
 931         goto free_hash;
 932     }
 933
 934     /* success! */
 935     rc=TRUE;
 936
 937 free_hash:
 938     CryptDestroyHash(hHash);
 939 free_key:
 940     CryptDestroyKey(hKey);
 941 free_protect_data:
 942     free_protect_data(&protect_data);
 943 free_context:
 944     CryptReleaseContext(hProv,0);
 945 finished:
 946     /* If some error occurred, and no error code was set, force one. */
 947     if (!rc && GetLastError()==ERROR_SUCCESS)
 948     {
 949         SetLastError(ERROR_INVALID_DATA);
 950     }
 951
 952     if (rc)
 953     {
 954         SetLastError(ERROR_SUCCESS);
 955
 956         TRACE_DATA_BLOB(pDataOut);
 957     }
 958
 959     TRACE("returning %s\n", rc ? "ok" : "FAIL");
 960
 961     return rc;
 962 }
 963
 964
 965 /***************************************************************************
 966  * CryptUnprotectData   [CRYPT32.@]
 967  *
 968  * Generate Plain data and Description from given Cipher and Entropy data.
 969  *
 970  * PARAMS
 971  *  pDataIn          [I] Cipher data to be decoded
 972  *  ppszDataDescr    [O] Optional Unicode string describing the Plain data
 973  *  pOptionalEntropy [I] Optional entropy data to adjust cipher, can be NULL
 974  *  pvReserved       [I] Reserved, must be NULL
 975  *  pPromptStruct    [I] Structure describing if/how to prompt during decoding
 976  *  dwFlags          [I] Flags describing options to the decoding
 977  *  pDataOut         [O] Resulting Plain data, from calls to CryptProtectData
 978  *
 979  * RETURNS
 980  *  TRUE  If a Plain was generated.
 981  *  FALSE If something failed and no Plain is available.
 982  *
 983  * FIXME
 984  *  The true Windows encryption and keying mechanisms are unknown.
 985  *
 986  *  dwFlags and pPromptStruct are currently ignored.
 987  *
 988  * NOTES
 989  *  Memory allocated in pDataOut and non-NULL ppszDataDescr must be freed
 990  *  with LocalFree.
 991  *
 992  */
 993 BOOL WINAPI CryptUnprotectData(DATA_BLOB* pDataIn,
 994                                LPWSTR * ppszDataDescr,
 995                                DATA_BLOB* pOptionalEntropy,
 996                                PVOID pvReserved,
 997                                CRYPTPROTECT_PROMPTSTRUCT* pPromptStruct,
 998                                DWORD dwFlags,
 999                                DATA_BLOB* pDataOut)
1000 {
1001     BOOL rc = FALSE;
1002
1003     HCRYPTPROV hProv;
1004     struct protect_data_t protect_data;
1005     HCRYPTHASH hHash;
1006     HCRYPTKEY hKey;
1007     DWORD dwLength;
1008
1009     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.";
1010
1011     TRACE("called\n");
1012
1013     SetLastError(ERROR_SUCCESS);
1014
1015     if (!pDataIn || !pDataOut)
1016     {
1017         SetLastError(ERROR_INVALID_PARAMETER);
1018         goto finished;
1019     }
1020     if (!pDataIn->cbData)
1021     {
1022         SetLastError(ERROR_INVALID_DATA);
1023         goto finished;
1024     }
1025
1026     /* debug: show our arguments */
1027     report(pDataIn,pOptionalEntropy,pPromptStruct,dwFlags);
1028     TRACE("\tppszDataDescr: %p\n", ppszDataDescr);
1029
1030     /* take apart the opaque blob */
1031     if (!unserialize(pDataIn, &protect_data))
1032     {
1033         SetLastError(ERROR_INVALID_DATA);
1034         FIXME("%s\n",announce_bad_opaque_data);
1035         goto finished;
1036     }
1037
1038     /* perform basic validation on the resulting structure */
1039     if (!valid_protect_data(&protect_data))
1040     {
1041         SetLastError(ERROR_INVALID_DATA);
1042         FIXME("%s\n",announce_bad_opaque_data);
1043         goto free_protect_data;
1044     }
1045
1046     /* get a crypt context */
1047     if (!CryptAcquireContextW(&hProv,NULL,MS_ENHANCED_PROV_W,CRYPT32_PROTECTDATA_PROV,CRYPT_VERIFYCONTEXT))
1048     {
1049         ERR("CryptAcquireContextW failed\n");
1050         goto free_protect_data;
1051     }
1052
1053     /* load key */
1054     if (!load_encryption_key(hProv,protect_data.cipher_key_len,&protect_data.salt,pOptionalEntropy,&hKey))
1055     {
1056         goto free_context;
1057     }
1058
1059     /* create a hash for the decryption validation */
1060     if (!CryptCreateHash(hProv,CRYPT32_PROTECTDATA_HASH_CALG,0,0,&hHash))
1061     {
1062         ERR("CryptCreateHash\n");
1063         goto free_key;
1064     }
1065
1066     /* prepare for plaintext */
1067     pDataOut->cbData=protect_data.cipher.cbData;
1068     if (!(pDataOut->pbData=LocalAlloc( LPTR, pDataOut->cbData)))
1069     {
1070         ERR("CryptMemAlloc\n");
1071         goto free_hash;
1072     }
1073     memcpy(pDataOut->pbData,protect_data.cipher.pbData,protect_data.cipher.cbData);
1074
1075     /* decrypt! */
1076     if (!CryptDecrypt(hKey, hHash, TRUE, 0, pDataOut->pbData,
1077                       &pDataOut->cbData) ||
1078         /* check the hash fingerprint */
1079         pDataOut->cbData > protect_data.cipher.cbData ||
1080         !hash_matches_blob(hHash, &protect_data.fingerprint))
1081     {
1082         SetLastError(ERROR_INVALID_DATA);
1083
1084         LocalFree( pDataOut->pbData );
1085         pDataOut->pbData = NULL;
1086         pDataOut->cbData = 0;
1087
1088         goto free_hash;
1089     }
1090
1091     /* Copy out the description */
1092     dwLength = (lstrlenW(protect_data.szDataDescr)+1) * sizeof(WCHAR);
1093     if (ppszDataDescr)
1094     {
1095         if (!(*ppszDataDescr = LocalAlloc(LPTR,dwLength)))
1096         {
1097             ERR("LocalAlloc (ppszDataDescr)\n");
1098             goto free_hash;
1099         }
1100         else {
1101             memcpy(*ppszDataDescr,protect_data.szDataDescr,dwLength);
1102         }
1103     }
1104
1105     /* success! */
1106     rc = TRUE;
1107
1108 free_hash:
1109     CryptDestroyHash(hHash);
1110 free_key:
1111     CryptDestroyKey(hKey);
1112 free_context:
1113     CryptReleaseContext(hProv,0);
1114 free_protect_data:
1115     free_protect_data(&protect_data);
1116 finished:
1117     /* If some error occurred, and no error code was set, force one. */
1118     if (!rc && GetLastError()==ERROR_SUCCESS)
1119     {
1120         SetLastError(ERROR_INVALID_DATA);
1121     }
1122
1123     if (rc) {
1124         SetLastError(ERROR_SUCCESS);
1125
1126         if (ppszDataDescr)
1127         {
1128             TRACE("szDataDescr: %s\n",debugstr_w(*ppszDataDescr));
1129         }
1130         TRACE_DATA_BLOB(pDataOut);
1131     }
1132
1133     TRACE("returning %s\n", rc ? "ok" : "FAIL");
1134
1135     return rc;
1136 }