ftparchive/cachedb.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: cachedb.cc,v 1.7 2004/05/08 19:41:01 mdz Exp $
   4 /* ######################################################################
   5
   6    CacheDB
   7
   8    Simple uniform interface to a cache database.
   9
  10    ##################################################################### */
  11                                                                         /*}}}*/
  12 // Include Files                                                        /*{{{*/
  13 #include <config.h>
  14
  15 #include <apt-pkg/error.h>
  16 #include <apt-pkg/md5.h>
  17 #include <apt-pkg/sha1.h>
  18 #include <apt-pkg/sha2.h>
  19 #include <apt-pkg/strutl.h>
  20 #include <apt-pkg/configuration.h>
  21 #include <apt-pkg/fileutl.h>
  22 #include <apt-pkg/debfile.h>
  23 #include <apt-pkg/gpgv.h>
  24
  25 #include <netinet/in.h>       // htonl, etc
  26 #include <ctype.h>
  27 #include <stddef.h>
  28 #include <sys/stat.h>
  29
  30 #include "cachedb.h"
  31
  32 #include <apti18n.h>
  33                                                                         /*}}}*/
  34
  35 // CacheDB::ReadyDB - Ready the DB2                                     /*{{{*/
  36 // ---------------------------------------------------------------------
  37 /* This opens the DB2 file for caching package information */
  38 bool CacheDB::ReadyDB(std::string const &DB)
  39 {
  40    int err;
  41
  42    ReadOnly = _config->FindB("APT::FTPArchive::ReadOnlyDB",false);
  43
  44    // Close the old DB
  45    if (Dbp != 0)
  46       Dbp->close(Dbp,0);
  47
  48    /* Check if the DB was disabled while running and deal with a
  49       corrupted DB */
  50    if (DBFailed() == true)
  51    {
  52       _error->Warning(_("DB was corrupted, file renamed to %s.old"),DBFile.c_str());
  53       rename(DBFile.c_str(),(DBFile+".old").c_str());
  54    }
  55
  56    DBLoaded = false;
  57    Dbp = 0;
  58    DBFile = std::string();
  59
  60    if (DB.empty())
  61       return true;
  62
  63    db_create(&Dbp, NULL, 0);
  64    if ((err = Dbp->open(Dbp, NULL, DB.c_str(), NULL, DB_BTREE,
  65                         (ReadOnly?DB_RDONLY:DB_CREATE),
  66                         0644)) != 0)
  67    {
  68       if (err == DB_OLD_VERSION)
  69       {
  70           _error->Warning(_("DB is old, attempting to upgrade %s"),DBFile.c_str());
  71           err = Dbp->upgrade(Dbp, DB.c_str(), 0);
  72           if (!err)
  73              err = Dbp->open(Dbp, NULL, DB.c_str(), NULL, DB_HASH,
  74                             (ReadOnly?DB_RDONLY:DB_CREATE), 0644);
  75
  76       }
  77       // the database format has changed from DB_HASH to DB_BTREE in
  78       // apt 0.6.44
  79       if (err == EINVAL)
  80       {
  81          _error->Error(_("DB format is invalid. If you upgraded from an older version of apt, please remove and re-create the database."));
  82       }
  83       if (err)
  84       {
  85           Dbp = 0;
  86           return _error->Error(_("Unable to open DB file %s: %s"),DB.c_str(), db_strerror(err));
  87       }
  88    }
  89
  90    DBFile = DB;
  91    DBLoaded = true;
  92    return true;
  93 }
  94                                                                         /*}}}*/
  95 // CacheDB::OpenFile - Open the file                                    /*{{{*/
  96 // ---------------------------------------------------------------------
  97 /* */
  98 bool CacheDB::OpenFile()
  99 {
 100    // its open already
 101    if(Fd && Fd->Name() == this->FileName)
 102       return true;
 103
 104    // a different file is open, close it first
 105    if(Fd && Fd->Name() != this->FileName)
 106       CloseFile();
 107
 108    // open a new file
 109    Fd = new FileFd(FileName,FileFd::ReadOnly);
 110    if (_error->PendingError() == true)
 111    {
 112       CloseFile();
 113       return false;
 114    }
 115    return true;
 116 }
 117                                                                         /*}}}*/
 118 // CacheDB::CloseFile - Close the file                                  /*{{{*/
 119 void CacheDB::CloseFile()
 120 {
 121    if(Fd != NULL)
 122    {
 123       delete Fd;
 124       Fd = NULL;
 125    }
 126 }
 127                                                                         /*}}}*/
 128 // CacheDB::OpenDebFile - Open a debfile                                /*{{{*/
 129 bool CacheDB::OpenDebFile()
 130 {
 131    // debfile is already open
 132    if(DebFile && &DebFile->GetFile() == Fd)
 133       return true;
 134
 135    // a different debfile is open, close it first
 136    if(DebFile && &DebFile->GetFile() != Fd)
 137       CloseDebFile();
 138
 139    // first open the fd, then pass it to the debDebFile
 140    if(OpenFile() == false)
 141       return false;
 142    DebFile = new debDebFile(*Fd);
 143    if (_error->PendingError() == true)
 144       return false;
 145    return true;
 146 }
 147                                                                         /*}}}*/
 148 // CacheDB::CloseDebFile - Close a debfile again                        /*{{{*/
 149 void CacheDB::CloseDebFile()
 150 {
 151    CloseFile();
 152
 153    if(DebFile != NULL)
 154    {
 155       delete DebFile;
 156       DebFile = NULL;
 157    }
 158 }
 159                                                                         /*}}}*/
 160 // CacheDB::GetFileStat - Get stats from the file                       /*{{{*/
 161 // ---------------------------------------------------------------------
 162 /* This gets the size from the database if it's there.  If we need
 163  * to look at the file, also get the mtime from the file. */
 164 bool CacheDB::GetFileStat(bool const &doStat)
 165 {
 166    if ((CurStat.Flags & FlSize) == FlSize && doStat == false)
 167       return true;
 168
 169    /* Get it from the file. */
 170    if (OpenFile() == false)
 171       return false;
 172
 173    // Stat the file
 174    struct stat St;
 175    if (fstat(Fd->Fd(),&St) != 0)
 176    {
 177       CloseFile();
 178       return _error->Errno("fstat",
 179                            _("Failed to stat %s"),FileName.c_str());
 180    }
 181    CurStat.FileSize = St.st_size;
 182    CurStat.mtime = htonl(St.st_mtime);
 183    CurStat.Flags |= FlSize;
 184
 185    return true;
 186 }
 187                                                                         /*}}}*/
 188 // CacheDB::GetCurStat - Set the CurStat variable.                      /*{{{*/
 189 // ---------------------------------------------------------------------
 190 /* Sets the CurStat variable.  Either to 0 if no database is used
 191  * or to the value in the database if one is used */
 192 bool CacheDB::GetCurStat()
 193 {
 194    memset(&CurStat,0,sizeof(CurStat));
 195
 196    if (DBLoaded)
 197    {
 198       /* First see if there is anything about it
 199          in the database */
 200
 201       /* Get the flags (and mtime) */
 202       InitQuery("st");
 203       // Ensure alignment of the returned structure
 204       Data.data = &CurStat;
 205       Data.ulen = sizeof(CurStat);
 206       Data.flags = DB_DBT_USERMEM;
 207       if (Get() == false)
 208       {
 209          CurStat.Flags = 0;
 210       }
 211       CurStat.Flags = ntohl(CurStat.Flags);
 212       CurStat.FileSize = ntohl(CurStat.FileSize);
 213    }
 214    return true;
 215 }
 216                                                                         /*}}}*/
 217 // CacheDB::GetFileInfo - Get all the info about the file               /*{{{*/
 218 // ---------------------------------------------------------------------
 219 bool CacheDB::GetFileInfo(std::string const &FileName, bool const &DoControl,
 220                           bool const &DoContents,
 221                           bool const &GenContentsOnly,
 222                           bool const &DoSource,
 223                           bool const &DoMD5, bool const &DoSHA1,
 224                           bool const &DoSHA256, bool const &DoSHA512,
 225                           bool const &checkMtime)
 226 {
 227    bool result = true;
 228    this->FileName = FileName;
 229
 230    if (GetCurStat() == false)
 231       return false;
 232    OldStat = CurStat;
 233
 234    if (GetFileStat(checkMtime) == false)
 235       return false;
 236
 237    /* if mtime changed, update CurStat from disk */
 238    if (checkMtime == true && OldStat.mtime != CurStat.mtime)
 239       CurStat.Flags = FlSize;
 240
 241    Stats.Bytes += CurStat.FileSize;
 242    Stats.Packages++;
 243
 244    if ((DoControl && LoadControl() == false)
 245        || (DoContents && LoadContents(GenContentsOnly) == false)
 246        || (DoSource && LoadSource() == false)
 247        || (DoMD5 && GetMD5(false) == false)
 248        || (DoSHA1 && GetSHA1(false) == false)
 249        || (DoSHA256 && GetSHA256(false) == false)
 250        || (DoSHA512 && GetSHA512(false) == false) )
 251    {
 252       result = false;
 253    }
 254
 255    return result;
 256 }
 257                                                                         /*}}}*/
 258
 259 bool CacheDB::LoadSource()
 260 {
 261    // Try to read the control information out of the DB.
 262    if ((CurStat.Flags & FlSource) == FlSource)
 263    {
 264       // Lookup the control information
 265       InitQuery("cs");
 266       if (Get() == true && Dsc.TakeDsc(Data.data, Data.size) == true)
 267             return true;
 268       CurStat.Flags &= ~FlSource;
 269    }
 270
 271    if (OpenFile() == false)
 272       return false;
 273
 274    Stats.Misses++;
 275    if (Dsc.Read(FileName) == false)
 276       return false;
 277
 278    if (Dsc.Data == 0)
 279       return _error->Error(_("Failed to read .dsc"));
 280
 281    // Write back the control information
 282    InitQuery("cs");
 283    if (Put(Dsc.Data, Dsc.Length) == true)
 284       CurStat.Flags |= FlSource;
 285
 286    return true;
 287 }
 288
 289 // CacheDB::LoadControl - Load Control information                      /*{{{*/
 290 // ---------------------------------------------------------------------
 291 /* */
 292 bool CacheDB::LoadControl()
 293 {
 294    // Try to read the control information out of the DB.
 295    if ((CurStat.Flags & FlControl) == FlControl)
 296    {
 297       // Lookup the control information
 298       InitQuery("cl");
 299       if (Get() == true && Control.TakeControl(Data.data,Data.size) == true)
 300             return true;
 301       CurStat.Flags &= ~FlControl;
 302    }
 303
 304    if(OpenDebFile() == false)
 305       return false;
 306
 307    Stats.Misses++;
 308    if (Control.Read(*DebFile) == false)
 309       return false;
 310
 311    if (Control.Control == 0)
 312       return _error->Error(_("Archive has no control record"));
 313
 314    // Write back the control information
 315    InitQuery("cl");
 316    if (Put(Control.Control,Control.Length) == true)
 317       CurStat.Flags |= FlControl;
 318    return true;
 319 }
 320                                                                         /*}}}*/
 321 // CacheDB::LoadContents - Load the File Listing                        /*{{{*/
 322 // ---------------------------------------------------------------------
 323 /* */
 324 bool CacheDB::LoadContents(bool const &GenOnly)
 325 {
 326    // Try to read the control information out of the DB.
 327    if ((CurStat.Flags & FlContents) == FlContents)
 328    {
 329       if (GenOnly == true)
 330          return true;
 331
 332       // Lookup the contents information
 333       InitQuery("cn");
 334       if (Get() == true)
 335       {
 336          if (Contents.TakeContents(Data.data,Data.size) == true)
 337             return true;
 338       }
 339
 340       CurStat.Flags &= ~FlContents;
 341    }
 342
 343    if(OpenDebFile() == false)
 344       return false;
 345
 346    Stats.Misses++;
 347    if (Contents.Read(*DebFile) == false)
 348       return false;
 349
 350    // Write back the control information
 351    InitQuery("cn");
 352    if (Put(Contents.Data,Contents.CurSize) == true)
 353       CurStat.Flags |= FlContents;
 354    return true;
 355 }
 356                                                                         /*}}}*/
 357
 358 static std::string bytes2hex(uint8_t *bytes, size_t length) {
 359    char buf[3];
 360    std::string space;
 361
 362    space.reserve(length*2 + 1);
 363    for (size_t i = 0; i < length; i++) {
 364       snprintf(buf, sizeof(buf), "%02x", bytes[i]);
 365       space.append(buf);
 366    }
 367    return space;
 368 }
 369
 370 static inline unsigned char xdig2num(char const &dig) {
 371    if (isdigit(dig)) return dig - '0';
 372    if ('a' <= dig && dig <= 'f') return dig - 'a' + 10;
 373    if ('A' <= dig && dig <= 'F') return dig - 'A' + 10;
 374    return 0;
 375 }
 376
 377 static void hex2bytes(uint8_t *bytes, const char *hex, int length) {
 378    while (length-- > 0) {
 379       *bytes = 0;
 380       if (isxdigit(hex[0]) && isxdigit(hex[1])) {
 381           *bytes = xdig2num(hex[0]) * 16 + xdig2num(hex[1]);
 382           hex += 2;
 383       }
 384       bytes++;
 385    }
 386 }
 387
 388 // CacheDB::GetMD5 - Get the MD5 hash                                   /*{{{*/
 389 // ---------------------------------------------------------------------
 390 /* */
 391 bool CacheDB::GetMD5(bool const &GenOnly)
 392 {
 393    // Try to read the control information out of the DB.
 394    if ((CurStat.Flags & FlMD5) == FlMD5)
 395    {
 396       if (GenOnly == true)
 397          return true;
 398
 399       MD5Res = bytes2hex(CurStat.MD5, sizeof(CurStat.MD5));
 400          return true;
 401    }
 402
 403    Stats.MD5Bytes += CurStat.FileSize;
 404
 405    if (OpenFile() == false)
 406       return false;
 407
 408    MD5Summation MD5;
 409    if (Fd->Seek(0) == false || MD5.AddFD(*Fd, CurStat.FileSize) == false)
 410       return false;
 411
 412    MD5Res = MD5.Result();
 413    hex2bytes(CurStat.MD5, MD5Res.data(), sizeof(CurStat.MD5));
 414       CurStat.Flags |= FlMD5;
 415    return true;
 416 }
 417                                                                         /*}}}*/
 418 // CacheDB::GetSHA1 - Get the SHA1 hash                                 /*{{{*/
 419 // ---------------------------------------------------------------------
 420 /* */
 421 bool CacheDB::GetSHA1(bool const &GenOnly)
 422 {
 423    // Try to read the control information out of the DB.
 424    if ((CurStat.Flags & FlSHA1) == FlSHA1)
 425    {
 426       if (GenOnly == true)
 427          return true;
 428
 429       SHA1Res = bytes2hex(CurStat.SHA1, sizeof(CurStat.SHA1));
 430       return true;
 431    }
 432
 433    Stats.SHA1Bytes += CurStat.FileSize;
 434
 435    if (OpenFile() == false)
 436       return false;
 437
 438    SHA1Summation SHA1;
 439    if (Fd->Seek(0) == false || SHA1.AddFD(*Fd, CurStat.FileSize) == false)
 440       return false;
 441
 442    SHA1Res = SHA1.Result();
 443    hex2bytes(CurStat.SHA1, SHA1Res.data(), sizeof(CurStat.SHA1));
 444    CurStat.Flags |= FlSHA1;
 445    return true;
 446 }
 447                                                                         /*}}}*/
 448 // CacheDB::GetSHA256 - Get the SHA256 hash                             /*{{{*/
 449 // ---------------------------------------------------------------------
 450 /* */
 451 bool CacheDB::GetSHA256(bool const &GenOnly)
 452 {
 453    // Try to read the control information out of the DB.
 454    if ((CurStat.Flags & FlSHA256) == FlSHA256)
 455    {
 456       if (GenOnly == true)
 457          return true;
 458
 459       SHA256Res = bytes2hex(CurStat.SHA256, sizeof(CurStat.SHA256));
 460       return true;
 461    }
 462
 463    Stats.SHA256Bytes += CurStat.FileSize;
 464
 465    if (OpenFile() == false)
 466       return false;
 467
 468    SHA256Summation SHA256;
 469    if (Fd->Seek(0) == false || SHA256.AddFD(*Fd, CurStat.FileSize) == false)
 470       return false;
 471
 472    SHA256Res = SHA256.Result();
 473    hex2bytes(CurStat.SHA256, SHA256Res.data(), sizeof(CurStat.SHA256));
 474    CurStat.Flags |= FlSHA256;
 475    return true;
 476 }
 477                                                                         /*}}}*/
 478 // CacheDB::GetSHA256 - Get the SHA256 hash                             /*{{{*/
 479 // ---------------------------------------------------------------------
 480 /* */
 481 bool CacheDB::GetSHA512(bool const &GenOnly)
 482 {
 483    // Try to read the control information out of the DB.
 484    if ((CurStat.Flags & FlSHA512) == FlSHA512)
 485    {
 486       if (GenOnly == true)
 487          return true;
 488
 489       SHA512Res = bytes2hex(CurStat.SHA512, sizeof(CurStat.SHA512));
 490       return true;
 491    }
 492
 493    Stats.SHA512Bytes += CurStat.FileSize;
 494
 495    if (OpenFile() == false)
 496       return false;
 497
 498    SHA512Summation SHA512;
 499    if (Fd->Seek(0) == false || SHA512.AddFD(*Fd, CurStat.FileSize) == false)
 500       return false;
 501
 502    SHA512Res = SHA512.Result();
 503    hex2bytes(CurStat.SHA512, SHA512Res.data(), sizeof(CurStat.SHA512));
 504    CurStat.Flags |= FlSHA512;
 505    return true;
 506 }
 507                                                                         /*}}}*/
 508 // CacheDB::Finish - Write back the cache structure                     /*{{{*/
 509 // ---------------------------------------------------------------------
 510 /* */
 511 bool CacheDB::Finish()
 512 {
 513    // Optimize away some writes.
 514    if (CurStat.Flags == OldStat.Flags &&
 515        CurStat.mtime == OldStat.mtime)
 516       return true;
 517
 518    // Write the stat information
 519    CurStat.Flags = htonl(CurStat.Flags);
 520    CurStat.FileSize = htonl(CurStat.FileSize);
 521    InitQuery("st");
 522    Put(&CurStat,sizeof(CurStat));
 523    CurStat.Flags = ntohl(CurStat.Flags);
 524    CurStat.FileSize = ntohl(CurStat.FileSize);
 525
 526    return true;
 527 }
 528                                                                         /*}}}*/
 529 // CacheDB::Clean - Clean the Database                                  /*{{{*/
 530 // ---------------------------------------------------------------------
 531 /* Tidy the database by removing files that no longer exist at all. */
 532 bool CacheDB::Clean()
 533 {
 534    if (DBLoaded == false)
 535       return true;
 536
 537    /* I'm not sure what VERSION_MINOR should be here.. 2.4.14 certainly
 538       needs the lower one and 2.7.7 needs the upper.. */
 539    DBC *Cursor;
 540    if ((errno = Dbp->cursor(Dbp, NULL, &Cursor, 0)) != 0)
 541       return _error->Error(_("Unable to get a cursor"));
 542
 543    DBT Key;
 544    DBT Data;
 545    memset(&Key,0,sizeof(Key));
 546    memset(&Data,0,sizeof(Data));
 547    while ((errno = Cursor->c_get(Cursor,&Key,&Data,DB_NEXT)) == 0)
 548    {
 549       const char *Colon = (char*)memrchr(Key.data, ':', Key.size);
 550       if (Colon)
 551       {
 552          if (stringcmp(Colon + 1, (char *)Key.data+Key.size,"st") == 0 ||
 553              stringcmp(Colon + 1, (char *)Key.data+Key.size,"cl") == 0 ||
 554              stringcmp(Colon + 1, (char *)Key.data+Key.size,"cn") == 0)
 555          {
 556             if (FileExists(std::string((const char *)Key.data,Colon)) == true)
 557                 continue;
 558          }
 559       }
 560
 561       Cursor->c_del(Cursor,0);
 562    }
 563    Dbp->compact(Dbp, NULL, NULL, NULL, NULL, DB_FREE_SPACE, NULL);
 564
 565    return true;
 566 }
 567                                                                         /*}}}*/