tool/dbhash.c

   1 /*
   2 ** 2016-06-07
   3 **
   4 ** The author disclaims copyright to this source code.  In place of
   5 ** a legal notice, here is a blessing:
   6 **
   7 **    May you do good and not evil.
   8 **    May you find forgiveness for yourself and forgive others.
   9 **    May you share freely, never taking more than you give.
  10 **
  11 *************************************************************************
  12 **
  13 ** This is a utility program that computes an SHA1 hash on the content
  14 ** of an SQLite database.
  15 **
  16 ** The hash is computed over just the content of the database.  Free
  17 ** space inside of the database file, and alternative on-disk representations
  18 ** of the same content (ex: UTF8 vs UTF16) do not affect the hash.  So,
  19 ** for example, the database file page size, encoding, and auto_vacuum setting
  20 ** can all be changed without changing the hash.
  21 */
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <stdarg.h>
  25 #include <ctype.h>
  26 #include <string.h>
  27 #include <assert.h>
  28 #include "sqlite3.h"
  29
  30 /* Context for the SHA1 hash */
  31 typedef struct SHA1Context SHA1Context;
  32 struct SHA1Context {
  33   unsigned int state[5];
  34   unsigned int count[2];
  35   unsigned char buffer[64];
  36 };
  37
  38 /*
  39 ** All global variables are gathered into the "g" singleton.
  40 */
  41 struct GlobalVars {
  42   const char *zArgv0;       /* Name of program */
  43   unsigned fDebug;          /* Debug flags */
  44   sqlite3 *db;              /* The database connection */
  45   SHA1Context cx;           /* SHA1 hash context */
  46 } g;
  47
  48 /*
  49 ** Debugging flags
  50 */
  51 #define DEBUG_FULLTRACE   0x00000001   /* Trace hash to stderr */
  52
  53 /******************************************************************************
  54 ** The Hash Engine
  55 **
  56 ** Modify these routines (and appropriate state fields in global variable 'g')
  57 ** in order to compute a different (better?) hash of the database.
  58 */
  59 /*
  60  * blk0() and blk() perform the initial expand.
  61  * I got the idea of expanding during the round function from SSLeay
  62  *
  63  * blk0le() for little-endian and blk0be() for big-endian.
  64  */
  65 #define SHA_ROT(x,l,r) ((x) << (l) | (x) >> (r))
  66 #define rol(x,k) SHA_ROT(x,k,32-(k))
  67 #define ror(x,k) SHA_ROT(x,32-(k),k)
  68
  69 #define blk0le(i) (block[i] = (ror(block[i],8)&0xFF00FF00) \
  70     |(rol(block[i],8)&0x00FF00FF))
  71 #define blk0be(i) block[i]
  72 #define blk(i) (block[i&15] = rol(block[(i+13)&15]^block[(i+8)&15] \
  73     ^block[(i+2)&15]^block[i&15],1))
  74
  75 /*
  76  * (R0+R1), R2, R3, R4 are the different operations (rounds) used in SHA1
  77  *
  78  * Rl0() for little-endian and Rb0() for big-endian.  Endianness is
  79  * determined at run-time.
  80  */
  81 #define Rl0(v,w,x,y,z,i) \
  82     z+=((w&(x^y))^y)+blk0le(i)+0x5A827999+rol(v,5);w=ror(w,2);
  83 #define Rb0(v,w,x,y,z,i) \
  84     z+=((w&(x^y))^y)+blk0be(i)+0x5A827999+rol(v,5);w=ror(w,2);
  85 #define R1(v,w,x,y,z,i) \
  86     z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=ror(w,2);
  87 #define R2(v,w,x,y,z,i) \
  88     z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=ror(w,2);
  89 #define R3(v,w,x,y,z,i) \
  90     z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=ror(w,2);
  91 #define R4(v,w,x,y,z,i) \
  92     z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=ror(w,2);
  93
  94 /*
  95  * Hash a single 512-bit block. This is the core of the algorithm.
  96  */
  97 #define a qq[0]
  98 #define b qq[1]
  99 #define c qq[2]
 100 #define d qq[3]
 101 #define e qq[4]
 102
 103 void SHA1Transform(unsigned int state[5], const unsigned char buffer[64]){
 104   unsigned int qq[5]; /* a, b, c, d, e; */
 105   static int one = 1;
 106   unsigned int block[16];
 107   memcpy(block, buffer, 64);
 108   memcpy(qq,state,5*sizeof(unsigned int));
 109
 110   /* Copy g.cx.state[] to working vars */
 111   /*
 112   a = state[0];
 113   b = state[1];
 114   c = state[2];
 115   d = state[3];
 116   e = state[4];
 117   */
 118
 119   /* 4 rounds of 20 operations each. Loop unrolled. */
 120   if( 1 == *(unsigned char*)&one ){
 121     Rl0(a,b,c,d,e, 0); Rl0(e,a,b,c,d, 1); Rl0(d,e,a,b,c, 2); Rl0(c,d,e,a,b, 3);
 122     Rl0(b,c,d,e,a, 4); Rl0(a,b,c,d,e, 5); Rl0(e,a,b,c,d, 6); Rl0(d,e,a,b,c, 7);
 123     Rl0(c,d,e,a,b, 8); Rl0(b,c,d,e,a, 9); Rl0(a,b,c,d,e,10); Rl0(e,a,b,c,d,11);
 124     Rl0(d,e,a,b,c,12); Rl0(c,d,e,a,b,13); Rl0(b,c,d,e,a,14); Rl0(a,b,c,d,e,15);
 125   }else{
 126     Rb0(a,b,c,d,e, 0); Rb0(e,a,b,c,d, 1); Rb0(d,e,a,b,c, 2); Rb0(c,d,e,a,b, 3);
 127     Rb0(b,c,d,e,a, 4); Rb0(a,b,c,d,e, 5); Rb0(e,a,b,c,d, 6); Rb0(d,e,a,b,c, 7);
 128     Rb0(c,d,e,a,b, 8); Rb0(b,c,d,e,a, 9); Rb0(a,b,c,d,e,10); Rb0(e,a,b,c,d,11);
 129     Rb0(d,e,a,b,c,12); Rb0(c,d,e,a,b,13); Rb0(b,c,d,e,a,14); Rb0(a,b,c,d,e,15);
 130   }
 131   R1(e,a,b,c,d,16); R1(d,e,a,b,c,17); R1(c,d,e,a,b,18); R1(b,c,d,e,a,19);
 132   R2(a,b,c,d,e,20); R2(e,a,b,c,d,21); R2(d,e,a,b,c,22); R2(c,d,e,a,b,23);
 133   R2(b,c,d,e,a,24); R2(a,b,c,d,e,25); R2(e,a,b,c,d,26); R2(d,e,a,b,c,27);
 134   R2(c,d,e,a,b,28); R2(b,c,d,e,a,29); R2(a,b,c,d,e,30); R2(e,a,b,c,d,31);
 135   R2(d,e,a,b,c,32); R2(c,d,e,a,b,33); R2(b,c,d,e,a,34); R2(a,b,c,d,e,35);
 136   R2(e,a,b,c,d,36); R2(d,e,a,b,c,37); R2(c,d,e,a,b,38); R2(b,c,d,e,a,39);
 137   R3(a,b,c,d,e,40); R3(e,a,b,c,d,41); R3(d,e,a,b,c,42); R3(c,d,e,a,b,43);
 138   R3(b,c,d,e,a,44); R3(a,b,c,d,e,45); R3(e,a,b,c,d,46); R3(d,e,a,b,c,47);
 139   R3(c,d,e,a,b,48); R3(b,c,d,e,a,49); R3(a,b,c,d,e,50); R3(e,a,b,c,d,51);
 140   R3(d,e,a,b,c,52); R3(c,d,e,a,b,53); R3(b,c,d,e,a,54); R3(a,b,c,d,e,55);
 141   R3(e,a,b,c,d,56); R3(d,e,a,b,c,57); R3(c,d,e,a,b,58); R3(b,c,d,e,a,59);
 142   R4(a,b,c,d,e,60); R4(e,a,b,c,d,61); R4(d,e,a,b,c,62); R4(c,d,e,a,b,63);
 143   R4(b,c,d,e,a,64); R4(a,b,c,d,e,65); R4(e,a,b,c,d,66); R4(d,e,a,b,c,67);
 144   R4(c,d,e,a,b,68); R4(b,c,d,e,a,69); R4(a,b,c,d,e,70); R4(e,a,b,c,d,71);
 145   R4(d,e,a,b,c,72); R4(c,d,e,a,b,73); R4(b,c,d,e,a,74); R4(a,b,c,d,e,75);
 146   R4(e,a,b,c,d,76); R4(d,e,a,b,c,77); R4(c,d,e,a,b,78); R4(b,c,d,e,a,79);
 147
 148   /* Add the working vars back into context.state[] */
 149   state[0] += a;
 150   state[1] += b;
 151   state[2] += c;
 152   state[3] += d;
 153   state[4] += e;
 154 }
 155
 156
 157 /* Initialize the SHA1 hash */
 158 static void hash_init(void){
 159   /* SHA1 initialization constants */
 160   g.cx.state[0] = 0x67452301;
 161   g.cx.state[1] = 0xEFCDAB89;
 162   g.cx.state[2] = 0x98BADCFE;
 163   g.cx.state[3] = 0x10325476;
 164   g.cx.state[4] = 0xC3D2E1F0;
 165   g.cx.count[0] = g.cx.count[1] = 0;
 166 }
 167
 168 /* Add new content to the SHA1 hash */
 169 static void hash_step(const unsigned char *data,  unsigned int len){
 170   unsigned int i, j;
 171
 172   j = g.cx.count[0];
 173   if( (g.cx.count[0] += len << 3) < j ){
 174     g.cx.count[1] += (len>>29)+1;
 175   }
 176   j = (j >> 3) & 63;
 177   if( (j + len) > 63 ){
 178     (void)memcpy(&g.cx.buffer[j], data, (i = 64-j));
 179     SHA1Transform(g.cx.state, g.cx.buffer);
 180     for(; i + 63 < len; i += 64){
 181       SHA1Transform(g.cx.state, &data[i]);
 182     }
 183     j = 0;
 184   }else{
 185     i = 0;
 186   }
 187   (void)memcpy(&g.cx.buffer[j], &data[i], len - i);
 188 }
 189
 190
 191 /* Add padding and compute and output the message digest. */
 192 static void hash_finish(const char *zName){
 193   unsigned int i;
 194   unsigned char finalcount[8];
 195   unsigned char digest[20];
 196   static const char zEncode[] = "0123456789abcdef";
 197   char zOut[41];
 198
 199   for (i = 0; i < 8; i++){
 200     finalcount[i] = (unsigned char)((g.cx.count[(i >= 4 ? 0 : 1)]
 201        >> ((3-(i & 3)) * 8) ) & 255); /* Endian independent */
 202   }
 203   hash_step((const unsigned char *)"\200", 1);
 204   while ((g.cx.count[0] & 504) != 448){
 205     hash_step((const unsigned char *)"\0", 1);
 206   }
 207   hash_step(finalcount, 8);  /* Should cause a SHA1Transform() */
 208   for (i = 0; i < 20; i++){
 209     digest[i] = (unsigned char)((g.cx.state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
 210   }
 211   for(i=0; i<20; i++){
 212     zOut[i*2] = zEncode[(digest[i]>>4)&0xf];
 213     zOut[i*2+1] = zEncode[digest[i] & 0xf];
 214   }
 215   zOut[i*2]= 0;
 216   printf("%s %s\n", zOut, zName);
 217 }
 218 /* End of the hashing logic
 219 *******************************************************************************/
 220
 221 /*
 222 ** Print an error resulting from faulting command-line arguments and
 223 ** abort the program.
 224 */
 225 static void cmdlineError(const char *zFormat, ...){
 226   va_list ap;
 227   fprintf(stderr, "%s: ", g.zArgv0);
 228   va_start(ap, zFormat);
 229   vfprintf(stderr, zFormat, ap);
 230   va_end(ap);
 231   fprintf(stderr, "\n\"%s --help\" for more help\n", g.zArgv0);
 232   exit(1);
 233 }
 234
 235 /*
 236 ** Print an error message for an error that occurs at runtime, then
 237 ** abort the program.
 238 */
 239 static void runtimeError(const char *zFormat, ...){
 240   va_list ap;
 241   fprintf(stderr, "%s: ", g.zArgv0);
 242   va_start(ap, zFormat);
 243   vfprintf(stderr, zFormat, ap);
 244   va_end(ap);
 245   fprintf(stderr, "\n");
 246   exit(1);
 247 }
 248
 249 /*
 250 ** Prepare a new SQL statement.  Print an error and abort if anything
 251 ** goes wrong.
 252 */
 253 static sqlite3_stmt *db_vprepare(const char *zFormat, va_list ap){
 254   char *zSql;
 255   int rc;
 256   sqlite3_stmt *pStmt;
 257
 258   zSql = sqlite3_vmprintf(zFormat, ap);
 259   if( zSql==0 ) runtimeError("out of memory");
 260   rc = sqlite3_prepare_v2(g.db, zSql, -1, &pStmt, 0);
 261   if( rc ){
 262     runtimeError("SQL statement error: %s\n\"%s\"", sqlite3_errmsg(g.db),
 263                  zSql);
 264   }
 265   sqlite3_free(zSql);
 266   return pStmt;
 267 }
 268 static sqlite3_stmt *db_prepare(const char *zFormat, ...){
 269   va_list ap;
 270   sqlite3_stmt *pStmt;
 271   va_start(ap, zFormat);
 272   pStmt = db_vprepare(zFormat, ap);
 273   va_end(ap);
 274   return pStmt;
 275 }
 276
 277 /*
 278 ** Compute the hash for all rows of the query formed from the printf-style
 279 ** zFormat and its argument.
 280 */
 281 static void hash_one_query(const char *zFormat, ...){
 282   va_list ap;
 283   sqlite3_stmt *pStmt;        /* The query defined by zFormat and "..." */
 284   int nCol;                   /* Number of columns in the result set */
 285   int i;                      /* Loop counter */
 286
 287   /* Prepare the query defined by zFormat and "..." */
 288   va_start(ap, zFormat);
 289   pStmt = db_vprepare(zFormat, ap);
 290   va_end(ap);
 291   nCol = sqlite3_column_count(pStmt);
 292
 293   /* Compute a hash over the result of the query */
 294   while( SQLITE_ROW==sqlite3_step(pStmt) ){
 295     for(i=0; i<nCol; i++){
 296       switch( sqlite3_column_type(pStmt,i) ){
 297         case SQLITE_NULL: {
 298           hash_step((const unsigned char*)"0",1);
 299           if( g.fDebug & DEBUG_FULLTRACE ) fprintf(stderr, "NULL\n");
 300           break;
 301         }
 302         case SQLITE_INTEGER: {
 303           sqlite3_uint64 u;
 304           int j;
 305           unsigned char x[8];
 306           sqlite3_int64 v = sqlite3_column_int64(pStmt,i);
 307           memcpy(&u, &v, 8);
 308           for(j=7; j>=0; j--){
 309             x[j] = u & 0xff;
 310             u >>= 8;
 311           }
 312           hash_step((const unsigned char*)"1",1);
 313           hash_step(x,8);
 314           if( g.fDebug & DEBUG_FULLTRACE ){
 315             fprintf(stderr, "INT %s\n", sqlite3_column_text(pStmt,i));
 316           }
 317           break;
 318         }
 319         case SQLITE_FLOAT: {
 320           sqlite3_uint64 u;
 321           int j;
 322           unsigned char x[8];
 323           double r = sqlite3_column_double(pStmt,i);
 324           memcpy(&u, &r, 8);
 325           for(j=7; j>=0; j--){
 326             x[j] = u & 0xff;
 327             u >>= 8;
 328           }
 329           hash_step((const unsigned char*)"2",1);
 330           hash_step(x,8);
 331           if( g.fDebug & DEBUG_FULLTRACE ){
 332             fprintf(stderr, "FLOAT %s\n", sqlite3_column_text(pStmt,i));
 333           }
 334           break;
 335         }
 336         case SQLITE_TEXT: {
 337           int n = sqlite3_column_bytes(pStmt, i);
 338           const unsigned char *z = sqlite3_column_text(pStmt, i);
 339           hash_step((const unsigned char*)"3", 1);
 340           hash_step(z, n);
 341           if( g.fDebug & DEBUG_FULLTRACE ){
 342             fprintf(stderr, "TEXT '%s'\n", sqlite3_column_text(pStmt,i));
 343           }
 344           break;
 345         }
 346         case SQLITE_BLOB: {
 347           int n = sqlite3_column_bytes(pStmt, i);
 348           const unsigned char *z = sqlite3_column_blob(pStmt, i);
 349           hash_step((const unsigned char*)"4", 1);
 350           hash_step(z, n);
 351           if( g.fDebug & DEBUG_FULLTRACE ){
 352             fprintf(stderr, "BLOB (%d bytes)\n", n);
 353           }
 354           break;
 355         }
 356       }
 357     }
 358   }
 359   sqlite3_finalize(pStmt);
 360 }
 361
 362
 363 /*
 364 ** Print sketchy documentation for this utility program
 365 */
 366 static void showHelp(void){
 367   printf("Usage: %s [options] FILE ...\n", g.zArgv0);
 368   printf(
 369 "Compute a SHA1 hash on the content of database FILE.  System tables such as\n"
 370 "sqlite_stat1, sqlite_stat4, and sqlite_sequence are omitted from the hash.\n"
 371 "Options:\n"
 372 "   --debug N           Set debugging flags to N (experts only)\n"
 373 "   --like PATTERN      Only hash tables whose name is LIKE the pattern\n"
 374 "   --schema-only       Only hash the schema - omit table content\n"
 375 "   --without-schema    Only hash table content - omit the schema\n"
 376   );
 377 }
 378
 379 int main(int argc, char **argv){
 380   const char *zDb = 0;         /* Name of the database currently being hashed */
 381   int i;                       /* Loop counter */
 382   int rc;                      /* Subroutine return code */
 383   char *zErrMsg;               /* Error message when opening database */
 384   sqlite3_stmt *pStmt;         /* An SQLite query */
 385   const char *zLike = 0;       /* LIKE pattern of tables to hash */
 386   int omitSchema = 0;          /* True to compute hash on content only */
 387   int omitContent = 0;         /* True to compute hash on schema only */
 388   int nFile = 0;               /* Number of input filenames seen */
 389
 390   g.zArgv0 = argv[0];
 391   sqlite3_config(SQLITE_CONFIG_SINGLETHREAD);
 392   for(i=1; i<argc; i++){
 393     const char *z = argv[i];
 394     if( z[0]=='-' ){
 395       z++;
 396       if( z[0]=='-' ) z++;
 397       if( strcmp(z,"debug")==0 ){
 398         if( i==argc-1 ) cmdlineError("missing argument to %s", argv[i]);
 399         g.fDebug = strtol(argv[++i], 0, 0);
 400       }else
 401       if( strcmp(z,"help")==0 ){
 402         showHelp();
 403         return 0;
 404       }else
 405       if( strcmp(z,"like")==0 ){
 406         if( i==argc-1 ) cmdlineError("missing argument to %s", argv[i]);
 407         if( zLike!=0 ) cmdlineError("only one --like allowed");
 408         zLike = argv[++i];
 409       }else
 410       if( strcmp(z,"schema-only")==0 ){
 411         omitContent = 1;
 412       }else
 413       if( strcmp(z,"without-schema")==0 ){
 414         omitSchema = 1;
 415       }else
 416       {
 417         cmdlineError("unknown option: %s", argv[i]);
 418       }
 419     }else{
 420       nFile++;
 421       if( nFile<i ) argv[nFile] = argv[i];
 422     }
 423   }
 424   if( nFile==0 ){
 425     cmdlineError("no input files specified - nothing to do");
 426   }
 427   if( omitSchema && omitContent ){
 428     cmdlineError("only one of --without-schema and --omit-schema allowed");
 429   }
 430   if( zLike==0 ) zLike = "%";
 431
 432   for(i=1; i<=nFile; i++){
 433     static const int openFlags =
 434        SQLITE_OPEN_READWRITE |     /* Read/write so hot journals can recover */
 435        SQLITE_OPEN_URI
 436     ;
 437     zDb = argv[i];
 438     rc = sqlite3_open_v2(zDb, &g.db, openFlags, 0);
 439     if( rc ){
 440       fprintf(stderr, "cannot open database file '%s'\n", zDb);
 441       continue;
 442     }
 443     rc = sqlite3_exec(g.db, "SELECT * FROM sqlite_schema", 0, 0, &zErrMsg);
 444     if( rc || zErrMsg ){
 445       sqlite3_close(g.db);
 446       g.db = 0;
 447       fprintf(stderr, "'%s' is not a valid SQLite database\n", zDb);
 448       continue;
 449     }
 450
 451     /* Start the hash */
 452     hash_init();
 453
 454     /* Hash table content */
 455     if( !omitContent ){
 456       pStmt = db_prepare(
 457         "SELECT name FROM sqlite_schema\n"
 458         " WHERE type='table' AND sql NOT LIKE 'CREATE VIRTUAL%%'\n"
 459         "   AND name NOT LIKE 'sqlite_%%'\n"
 460         "   AND name LIKE '%q'\n"
 461         " ORDER BY name COLLATE nocase;\n",
 462         zLike
 463       );
 464       while( SQLITE_ROW==sqlite3_step(pStmt) ){
 465         /* We want rows of the table to be hashed in PRIMARY KEY order.
 466         ** Technically, an ORDER BY clause is required to guarantee that
 467         ** order.  However, though not guaranteed by the documentation, every
 468         ** historical version of SQLite has always output rows in PRIMARY KEY
 469         ** order when there is no WHERE or GROUP BY clause, so the ORDER BY
 470         ** can be safely omitted. */
 471         hash_one_query("SELECT * FROM \"%w\"", sqlite3_column_text(pStmt,0));
 472       }
 473       sqlite3_finalize(pStmt);
 474     }
 475
 476     /* Hash the database schema */
 477     if( !omitSchema ){
 478       hash_one_query(
 479          "SELECT type, name, tbl_name, sql FROM sqlite_schema\n"
 480          " WHERE tbl_name LIKE '%q'\n"
 481          " ORDER BY name COLLATE nocase;\n",
 482          zLike
 483       );
 484     }
 485
 486     /* Finish and output the hash and close the database connection. */
 487     hash_finish(zDb);
 488     sqlite3_close(g.db);
 489   }
 490   return 0;
 491 }