mdw@git.distorted.org.uk Git - catacomb/blob - progs/cc-hash.c

   1 /* -*-c-*-
   2  *
   3  * Common functions for hashing utilities
   4  *
   5  * (c) 2011 Straylight/Edgeware
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of Catacomb.
  11  *
  12  * Catacomb is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU Library General Public License as
  14  * published by the Free Software Foundation; either version 2 of the
  15  * License, or (at your option) any later version.
  16  *
  17  * Catacomb is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU Library General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Library General Public
  23  * License along with Catacomb; if not, write to the Free
  24  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  25  * MA 02111-1307, USA.
  26  */
  27
  28 /*----- Header files ------------------------------------------------------*/
  29
  30 #define _FILE_OFFSET_BITS 64
  31
  32 #include "config.h"
  33
  34 #include <ctype.h>
  35 #include <errno.h>
  36 #include <stdio.h>
  37 #include <stdlib.h>
  38 #include <string.h>
  39
  40 #include <sys/types.h>
  41 #include <dirent.h>
  42
  43 #include <mLib/alloc.h>
  44 #include <mLib/dstr.h>
  45 #include <mLib/macros.h>
  46 #include <mLib/report.h>
  47 #include <mLib/str.h>
  48
  49 #include <mLib/hex.h>
  50 #include <mLib/base32.h>
  51 #include <mLib/base64.h>
  52
  53 #include "ghash.h"
  54 #include "cc.h"
  55
  56 /*----- Encoding and decoding ---------------------------------------------*/
  57
  58 /* --- Hex encoding --- */
  59
  60 static void puthex(const octet *buf, size_t sz, FILE *fp)
  61 {
  62   while (sz) {
  63     fprintf(fp, "%02x", *buf++);
  64     sz--;
  65   }
  66 }
  67
  68 static size_t gethex(const char *p, octet *q, size_t sz, char **pp)
  69 {
  70   size_t i = 0;
  71   while (sz > 0 && ISXDIGIT(p[0]) && ISXDIGIT(p[1])) {
  72     char buf[3];
  73     buf[0] = p[0];
  74     buf[1] = p[1];
  75     buf[2] = 0;
  76     *q++ = strtoul(buf, 0, 16);
  77     sz--;
  78     p += 2;
  79     i++;
  80   }
  81   if (pp)
  82     *pp = (char *)p;
  83   return (i);
  84 }
  85
  86 /* --- Base64 encoding --- */
  87
  88 static void putbase64(const octet *buf, size_t sz, FILE *fp)
  89 {
  90   base64_ctx b;
  91   dstr d = DSTR_INIT;
  92
  93   base64_init(&b);
  94   b.indent = "";
  95   b.maxline = 0;
  96   base64_encode(&b, buf, sz, &d);
  97   base64_encode(&b, 0, 0, &d);
  98   dstr_write(&d, fp);
  99   dstr_destroy(&d);
 100 }
 101
 102 static size_t getbase64(const char *p, octet *q, size_t sz, char **pp)
 103 {
 104   base64_ctx b;
 105   dstr d = DSTR_INIT;
 106   size_t n = strlen(p);
 107
 108   base64_init(&b);
 109   base64_decode(&b, p, n, &d);
 110   if (pp) *pp = (/*unconst*/ char *)p + n;
 111   base64_decode(&b, 0, 0, &d);
 112   assert(d.len <= sz);
 113   memcpy(q, d.buf, sz);
 114   n = d.len;
 115   dstr_destroy(&d);
 116   return (n);
 117 }
 118
 119 /* --- Base32 encoding --- */
 120
 121 static void putbase32(const octet *buf, size_t sz, FILE *fp)
 122 {
 123   base32_ctx b;
 124   dstr d = DSTR_INIT;
 125
 126   base32_init(&b);
 127   b.indent = "";
 128   b.maxline = 0;
 129   base32_encode(&b, buf, sz, &d);
 130   base32_encode(&b, 0, 0, &d);
 131   dstr_write(&d, fp);
 132   dstr_destroy(&d);
 133 }
 134
 135 static size_t getbase32(const char *p, octet *q, size_t sz, char **pp)
 136 {
 137   base32_ctx b;
 138   dstr d = DSTR_INIT;
 139   size_t n = strlen(p);
 140
 141   base32_init(&b);
 142   base32_decode(&b, p, n, &d);
 143   if (pp) *pp = (/*unconst*/ char *)p + n;
 144   base32_decode(&b, 0, 0, &d);
 145   assert(d.len <= sz);
 146   memcpy(q, d.buf, sz);
 147   n = d.len;
 148   dstr_destroy(&d);
 149   return (n);
 150 }
 151
 152 /* --- Table --- */
 153
 154 const encodeops encodingtab[] = {
 155 #define TAB(tag, name) { #name, put##name, get##name },
 156   ENCODINGS(TAB)
 157 #undef TAB
 158   { 0, 0, 0 }
 159 };
 160
 161 const encodeops *getencoding(const char *ename)
 162 {
 163   const encodeops *e;
 164
 165   for (e = encodingtab; e->name; e++) {
 166     if (STRCMP(ename, ==, e->name))
 167       return (e);
 168   }
 169   return (0);
 170 }
 171
 172 /*----- File hashing ------------------------------------------------------*/
 173
 174 enum {
 175   FHETY_DIR,
 176   FHETY_FILE
 177 };
 178
 179 typedef struct fhent {
 180   struct fhent *next;
 181   unsigned ty;
 182   struct fhent *sub;
 183   char name[1];
 184 } fhdir;
 185
 186 /* --- @gethash@ --- *
 187  *
 188  * Arguments:   @const char *name@ = pointer to name string
 189  *
 190  * Returns:     Pointer to appropriate hash class.
 191  *
 192  * Use:         Chooses a hash function by name.
 193  */
 194
 195 const gchash *gethash(const char *name)
 196 {
 197   const gchash *const *g, *gg = 0;
 198   size_t sz = strlen(name);
 199   for (g = ghashtab; *g; g++) {
 200     if (STRNCMP(name, ==, (*g)->name, sz)) {
 201       if ((*g)->name[sz] == 0) {
 202         gg = *g;
 203         break;
 204       } else if (gg)
 205         return (0);
 206       else
 207         gg = *g;
 208     }
 209   }
 210   return (gg);
 211 }
 212
 213 /* --- @describefile@ --- *
 214  *
 215  * Arguments:   @const struct stat *st@ = pointer to file state
 216  *
 217  * Returns:     A snappy one-word description of the file.
 218  */
 219
 220 const char *describefile(const struct stat *st)
 221 {
 222   switch (st->st_mode & S_IFMT) {
 223     case S_IFBLK: return ("block-special");
 224     case S_IFCHR: return ("char-special");
 225     case S_IFIFO: return ("fifo");
 226     case S_IFREG: return ("file");
 227     case S_IFLNK: return ("symlink");
 228     case S_IFDIR: return ("directory");
 229     case S_IFSOCK: return ("socket");
 230     default: return ("unknown");
 231   }
 232 }
 233
 234 /* --- @fhash_init@ ---*
 235  *
 236  * Arguments:   @fhashstate *fh@ = pointer to fhash state to initialize
 237  *              @const gchash *gch@ = hash class to set
 238  *              @unsigned f@ initial flags to set
 239  *
 240  * Returns:     ---
 241  *
 242  * Use:         Initializes an @fhashstate@ structure.
 243  */
 244
 245 void fhash_init(fhashstate *fh, const gchash *gch, unsigned f)
 246   { fh->f = f; fh->gch = gch; fh->ents = 0; }
 247
 248 /* --- @fhash_free@ --- *
 249  *
 250  * Arguments:   @fhashstate *fh@ = pointer to fhash state to free
 251  *
 252  * Returns:     ---
 253  *
 254  * Use:         Frees an fhash state.
 255  */
 256
 257 static void freefhents(struct fhent *fhe)
 258 {
 259   struct fhent *ffhe;
 260
 261   for (; fhe; fhe = ffhe) {
 262     ffhe = fhe->next;
 263     freefhents(fhe->sub);
 264     xfree(fhe);
 265   }
 266 }
 267
 268 void fhash_free(fhashstate *fh)
 269   { freefhents(fh->ents); }
 270
 271 /* --- @fhash@ --- *
 272  *
 273  * Arguments:   @fhashstate *fh@ = pointer to fhash state
 274  *              @const char *file@ = file name to be hashed (null for stdin)
 275  *              @void *buf@ = pointer to hash output buffer
 276  *
 277  * Returns:     Zero if it worked, nonzero on error.
 278  *
 279  * Use:         Hashes a file.
 280  */
 281
 282 int fhash(fhashstate *fh, const char *file, void *buf)
 283 {
 284   FILE *fp;
 285   char fbuf[1024 * 128];
 286   size_t sz;
 287   ghash *h;
 288   int rc = 0;
 289   struct fhent *fhe, **ffhe;
 290   const char *p, *q;
 291   size_t n;
 292   fprogress ff;
 293
 294   if (!file || STRCMP(file, ==, "-"))
 295     fp = stdin;
 296   else if ((fp = fopen(file, fh->f & FHF_BINARY ? "rb" : "r")) == 0)
 297     return (-1);
 298
 299   if (fh->f & FHF_PROGRESS) {
 300     if (fprogress_init(&ff, file ? file : "<stdin>", fp)) return (-1);
 301   }
 302
 303   if (fh->f & FHF_JUNK) {
 304     p = file;
 305     if (STRNCMP(p, ==, "./", 2)) p += 2;
 306     q = p;
 307     ffhe = &fh->ents;
 308     for (;;) {
 309       if (*q == '/' || *q == 0) {
 310         n = q - p;
 311         for (; *ffhe; ffhe = &(*ffhe)->next) {
 312           fhe = *ffhe;
 313           if (STRNCMP(p, ==, fhe->name, n) && fhe->name[n] == 0)
 314             goto found;
 315         }
 316         fhe = xmalloc(offsetof(struct fhent, name) + n + 1);
 317         fhe->next = 0;
 318         fhe->ty = *q == '/' ? FHETY_DIR : FHETY_FILE;
 319         fhe->sub = 0;
 320         *ffhe = fhe;
 321         memcpy(fhe->name, p, n); fhe->name[n] = 0;
 322       found:
 323         if (!*q) break;
 324         while (*++q == '/');
 325         p = q;
 326         ffhe = &fhe->sub;
 327       } else
 328         q++;
 329     }
 330   }
 331
 332   h = GH_INIT(fh->gch);
 333   while ((sz = fread(fbuf, 1, sizeof(fbuf), fp)) > 0) {
 334     GH_HASH(h, fbuf, sz);
 335     if (fh->f & FHF_PROGRESS) fprogress_update(&ff, sz);
 336   }
 337   if (ferror(fp)) rc = -1;
 338   if (fp != stdin) fclose(fp);
 339   if (fh->f & FHF_PROGRESS) fprogress_done(&ff);
 340   GH_DONE(h, buf);
 341   GH_DESTROY(h);
 342   return (rc);
 343 }
 344
 345 /* --- @fhash_junk@ --- *
 346  *
 347  * Arguments:   @fhashstate *fh@ = pointer to fhash state
 348  *              @void (*func)(const char *, const struct stat *, void *)@
 349  *              @void *p@ = pointer to pass to function
 350  *
 351  * Returns:     Positive if any junk was found, negative on error, zero if
 352  *              everything was fine.
 353  *
 354  * Use:         Reports junk files in any directories covered by the hash
 355  *              state.
 356  */
 357
 358 struct fhjunk {
 359   int (*func)(const char *, const struct stat *, void *);
 360   void *p;
 361   dstr *d;
 362 };
 363
 364 static int fhjunk(struct fhjunk *fhj, struct fhent *ents)
 365 {
 366   DIR *dp;
 367   int rc = 0, rrc;
 368   struct stat st;
 369   struct dirent *d;
 370   const char *dname;
 371   size_t n = fhj->d->len;
 372   struct fhent *fhe;
 373
 374   dname = n ? fhj->d->buf : ".";
 375   if ((dp = opendir(dname)) == 0) {
 376     moan("failed to open directory `%s': %s", dname, strerror(errno));
 377     rc = -1;
 378     goto subs;
 379   }
 380   if (n) {
 381     dstr_putc(fhj->d, '/');
 382     n++;
 383   }
 384   while (errno = 0, (d = readdir(dp)) != 0) {
 385     if (STRCMP(d->d_name, ==, ".") || STRCMP(d->d_name, ==, ".."))
 386       continue;
 387     for (fhe = ents; fhe; fhe = fhe->next) {
 388       if (STRCMP(d->d_name, ==, fhe->name)) goto found;
 389     }
 390     fhj->d->len = n;
 391     dstr_puts(fhj->d, d->d_name);
 392     if (!lstat(fhj->d->buf, &st)) {
 393       if (!rc) rc = 1;
 394       rrc = fhj->func(fhj->d->buf, &st, fhj->p);
 395     } else {
 396       rc = -1;
 397       rrc = fhj->func(fhj->d->buf, 0, fhj->p);
 398     }
 399     if (rrc < 0) rc = -1;
 400   found:;
 401   }
 402   closedir(dp);
 403   if (errno) {
 404     moan("failed to read directory `%s': %s", dname, strerror(errno));
 405     rc = -1;
 406   }
 407
 408 subs:
 409   for (fhe = ents; fhe; fhe = fhe->next) {
 410     if (fhe->ty == FHETY_DIR) {
 411       fhj->d->len = n;
 412       dstr_puts(fhj->d, fhe->name);
 413       rrc = fhjunk(fhj, fhe->sub);
 414       if (rrc < 0) rc = -1;
 415       else if (!rc) rc = rrc;
 416     }
 417   }
 418
 419   return (rc);
 420 }
 421
 422 int fhash_junk(fhashstate *fh,
 423                int (*func)(const char *, const struct stat *, void *),
 424                void *p)
 425 {
 426   dstr d = DSTR_INIT;
 427   struct fhjunk fhj;
 428   int rc;
 429
 430   fhj.func = func;
 431   fhj.p = p;
 432   fhj.d = &d;
 433   rc = fhjunk(&fhj, fh->ents);
 434   dstr_destroy(&d);
 435   return (rc);
 436 }
 437
 438 /* --- @hfparse@ --- *
 439  *
 440  * Arguments:   @hfpctx *hfp@ = pointer to the context structure
 441  *
 442  * Returns:     A code indicating what happened.
 443  *
 444  * Use:         Parses a line from the input file.
 445  */
 446
 447 int hfparse(hfpctx *hfp)
 448 {
 449   char *p, *q;
 450   const gchash *gch;
 451   const encodeops *ee;
 452   dstr *d = hfp->dline;
 453   size_t hsz;
 454
 455   /* --- Fetch the input line and get ready to parse --- */
 456
 457   DRESET(d);
 458   if (dstr_putline(d, hfp->fp) == EOF) return (HF_EOF);
 459   p = d->buf;
 460
 461   /* --- Parse magic comments --- */
 462
 463   if (*p == '#') {
 464     p++;
 465     if ((q = str_getword(&p)) == 0) return (HF_BAD);
 466     if (STRCMP(q, ==, "hash")) {
 467       if ((q = str_getword(&p)) == 0) return (HF_BAD);
 468       if ((gch = gethash(q)) == 0) return (HF_BAD);
 469       hfp->gch = gch;
 470       return (HF_HASH);
 471     } else if (STRCMP(q, ==, "encoding")) {
 472       if ((q = str_getword(&p)) == 0) return (HF_BAD);
 473       if ((ee = getencoding(q)) == 0) return (HF_BAD);
 474       hfp->ee = ee;
 475       return (HF_ENC);
 476     } else if (STRCMP(q, ==, "escape")) {
 477       hfp->f |= HFF_ESCAPE;
 478       return (HF_ESC);
 479     }
 480     return (HF_BAD);
 481   }
 482
 483   /* --- Otherwise it's a file line --- */
 484
 485   q = p;
 486   while (*p && *p != ' ') p++;
 487   if (!*p) return (HF_BAD);
 488   *p++ = 0;
 489   hsz = hfp->gch->hashsz;
 490   if (hfp->ee->get(q, hfp->hbuf, hsz, 0) < hsz) return (HF_BAD);
 491   switch (*p) {
 492     case '*': hfp->f |= FHF_BINARY; break;
 493     case ' ': hfp->f &= ~FHF_BINARY; break;
 494     default: return (HF_BAD);
 495   }
 496   p++;
 497
 498   DRESET(hfp->dfile);
 499   if (hfp->f & HFF_ESCAPE)
 500     getstring(&p, hfp->dfile, GSF_STRING);
 501   else {
 502     dstr_putm(hfp->dfile, p, d->len - (p - d->buf));
 503     dstr_putz(hfp->dfile);
 504   }
 505
 506   return (HF_FILE);
 507 }
 508
 509 /*----- String I/O --------------------------------------------------------*/
 510
 511 /* --- @getstring@ --- *
 512  *
 513  * Arguments:   @void *in@ = input source
 514  *              @dstr *d@ = destination string
 515  *              @unsigned f@ = input flags
 516  *
 517  * Returns:     Zero if OK, nonzero on end-of-file.
 518  *
 519  * Use:         Reads a filename (or something similar) from a stream.
 520  */
 521
 522 static int nextch_file(void *in)
 523   { FILE *fp = in; return (getc(fp)); }
 524
 525 static int nextch_string(void *in)
 526   { const unsigned char **p = in; return (*(*p)++); }
 527
 528 int getstring(void *in, dstr *d, unsigned f)
 529 {
 530   int ch;
 531   int eofch = (f & GSF_STRING) ? 0 : EOF;
 532   int (*nextch)(void *) = (f & GSF_STRING) ? nextch_string : nextch_file;
 533   int q = 0;
 534
 535   /* --- Raw: just read exactly what's written up to a null byte --- */
 536
 537   if (f & GSF_RAW) {
 538     if ((ch = nextch(in)) == eofch)
 539       return (EOF);
 540     for (;;) {
 541       if (!ch)
 542         break;
 543       DPUTC(d, ch);
 544       if ((ch = nextch(in)) == eofch)
 545         break;
 546     }
 547     DPUTZ(d);
 548     return (0);
 549   }
 550
 551   /* --- Skip as far as whitespace --- *
 552    *
 553    * Also skip past comments.
 554    */
 555
 556 again:
 557   ch = nextch(in);
 558   while (ISSPACE(ch))
 559     ch = nextch(in);
 560   if (ch == '#') {
 561     do ch = nextch(in); while (ch != '\n' && ch != eofch);
 562     goto again;
 563   }
 564   if (ch == eofch)
 565     return (EOF);
 566
 567   /* --- If the character is a quote then read a quoted string --- */
 568
 569   switch (ch) {
 570     case '`':
 571       ch = '\'';
 572     case '\'':
 573     case '\"':
 574       q = ch;
 575       ch = nextch(in);
 576       break;
 577   }
 578
 579   /* --- Now read all sorts of interesting things --- */
 580
 581   for (;;) {
 582
 583     /* --- Handle an escaped thing --- */
 584
 585     if (ch == '\\') {
 586       ch = nextch(in);
 587       if (ch == eofch)
 588         break;
 589       switch (ch) {
 590         case 'a': ch = '\a'; break;
 591         case 'b': ch = '\b'; break;
 592         case 'f': ch = '\f'; break;
 593         case 'n': ch = '\n'; break;
 594         case 'r': ch = '\r'; break;
 595         case 't': ch = '\t'; break;
 596         case 'v': ch = '\v'; break;
 597       }
 598       DPUTC(d, ch);
 599       ch = nextch(in);
 600       continue;
 601     }
 602
 603     /* --- If it's a quote or some other end marker then stop --- */
 604
 605     if (ch == q)
 606       break;
 607     if (!q && ISSPACE(ch))
 608       break;
 609
 610     /* --- Otherwise contribute and continue --- */
 611
 612     DPUTC(d, ch);
 613     if ((ch = nextch(in)) == eofch)
 614       break;
 615   }
 616
 617   /* --- Done --- */
 618
 619   DPUTZ(d);
 620   return (0);
 621 }
 622
 623 /* --- @putstring@ --- *
 624  *
 625  * Arguments:   @FILE *fp@ = stream to write on
 626  *              @const char *p@ = pointer to text
 627  *              @unsigned f@ = output flags
 628  *
 629  * Returns:     ---
 630  *
 631  * Use:         Emits a string to a stream.
 632  */
 633
 634 void putstring(FILE *fp, const char *p, unsigned f)
 635 {
 636   size_t sz = strlen(p);
 637   unsigned qq;
 638   const char *q;
 639
 640   /* --- Just write the string null terminated if raw --- */
 641
 642   if (f & GSF_RAW) {
 643     fwrite(p, 1, sz + 1, fp);
 644     return;
 645   }
 646
 647   /* --- Check for any dodgy characters --- */
 648
 649   qq = 0;
 650   for (q = p; *q; q++) {
 651     if (ISSPACE(*q)) {
 652       qq = '\"';
 653       break;
 654     }
 655   }
 656
 657   if (qq)
 658     putc(qq, fp);
 659
 660   /* --- Emit the string --- */
 661
 662   for (q = p; *q; q++) {
 663     switch (*q) {
 664       case '\a': fputc('\\', fp); fputc('a',  fp); break;
 665       case '\b': fputc('\\', fp); fputc('b',  fp); break;
 666       case '\f': fputc('\\', fp); fputc('f',  fp); break;
 667       case '\n': fputc('\\', fp); fputc('n',  fp); break;
 668       case '\r': fputc('\\', fp); fputc('r',  fp); break;
 669       case '\t': fputc('\\', fp); fputc('t',  fp); break;
 670       case '\v': fputc('\\', fp); fputc('v',  fp); break;
 671       case '`':  fputc('\\', fp); fputc('`',  fp); break;
 672       case '\'': fputc('\\', fp); fputc('\'', fp); break;
 673       case '\"': fputc('\\', fp); fputc('\"', fp); break;
 674       default:
 675         putc(*q, fp);
 676         break;
 677     }
 678   }
 679
 680   /* --- Done --- */
 681
 682   if (qq)
 683     putc(qq, fp);
 684 }
 685
 686 /*----- That's all, folks -------------------------------------------------*/