src/libupkg.c

   1 /*
   2  *  upkg: tool for manipulating Unreal Tournament packages.
   3  *  Copyright © 2009-2011 Nick Bowler
   4  *
   5  *  This program is free software: you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation, either version 3 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <string.h>
  22
  23 #include "upkg.h"
  24 #include "pack.h"
  25
  26 #define MIN(a, b) ((a) < (b) ? (a) : (b))
  27
  28 /*
  29  * Print a message and execute some statement(s) if the expression evaluates
  30  * to zero.  Intended to help verify that assumed constraints on the file
  31  * format actually are not violated.
  32  */
  33 #define format_assert(expr, body) do { \
  34         if (!(expr)) { \
  35                 fprintf(stderr, "%s: %d: %s: format assertion failed: %s\n", \
  36                                 __FILE__, __LINE__, __func__, #expr); \
  37                 body; \
  38         } \
  39 } while (0)
  40
  41 struct upkg_name {
  42         unsigned long flags;
  43         char *name;
  44 };
  45
  46 struct upkg_export_priv {
  47         struct upkg_export pub;
  48
  49         long class, super;
  50         unsigned long size, offset;
  51 };
  52
  53 struct upkg_import {
  54         const char *class_package, *class_name, *object_name;
  55         long package;
  56 };
  57
  58 struct upkg_priv {
  59         struct upkg pub;
  60
  61         const struct upkg_file_ops *fops;
  62         int (*dtor)(void *handle);
  63         void *f;
  64
  65         struct upkg_file *last_file;
  66
  67         struct upkg_name        *names;
  68         struct upkg_export_priv *exports;
  69         struct upkg_import      *imports;
  70
  71         unsigned long name_offset, export_offset, import_offset;
  72         unsigned char guid[16];
  73 };
  74
  75 /* Default I/O operations for ordinary files. */
  76 static size_t file_read(void *buf, size_t size, void *handle)
  77 {
  78         return fread(buf, 1, size, (FILE *)handle);
  79 }
  80
  81 static int file_seek(void *handle, long offset, int whence)
  82 {
  83         return fseek((FILE *)handle, offset, whence);
  84 }
  85
  86 static long file_tell(void *handle)
  87 {
  88         return ftell((FILE *)handle);
  89 }
  90
  91 static int file_eof(void *handle)
  92 {
  93         return feof((FILE *)handle);
  94 }
  95
  96 static int file_close(void *handle)
  97 {
  98         return fclose((FILE *)handle);
  99 }
 100
 101 const struct upkg_file_ops upkg_default_fops = {
 102         .read = file_read,
 103         .seek = file_seek,
 104         .tell = file_tell,
 105         .eof  = file_eof,
 106 };
 107
 108 /*
 109  * Decode the compact index format from the upkg.  This format is fucked.
 110  * Stores the result in *val and returns the number of input bytes read (or 0
 111  * if the input is invalid, in which case *val is undefined).
 112  */
 113 size_t upkg_decode_index(long *val, unsigned char *bytes, size_t n)
 114 {
 115         *val = 0;
 116
 117         for (size_t i = 0; i < MIN(n, 5); i++) {
 118                 /*
 119                  * Least significant bytes are first, so we need to do this
 120                  * nonsense.
 121                  */
 122                 long tmp = bytes[i] & (i == 0 ? 0x3f : 0x7f);
 123
 124                 if (i > 0) tmp <<= 6;
 125                 if (i > 1) tmp <<= 7*(i-1);
 126                 *val += tmp;
 127
 128                 if (!(bytes[i] & (i == 0 ? 0x40 : 0x80))) {
 129                         if (bytes[0] & 0x80)
 130                                 *val = -*val;
 131                         return i+1;
 132                 }
 133         }
 134
 135         /* Error */
 136         return 0;
 137 }
 138
 139 static struct upkg_priv *init_upkg(unsigned char hdr[static UPKG_HDR_SIZE])
 140 {
 141         struct upkg_priv *pkg;
 142
 143         pkg = malloc(sizeof *pkg);
 144         if (!pkg)
 145                 return NULL;
 146
 147         *pkg = (struct upkg_priv) {
 148                 .pub = {
 149                         .version      = unpack_16_le(hdr+4),
 150                         .license      = unpack_16_le(hdr+6),
 151                         .flags        = unpack_32_le(hdr+8),
 152                         .name_count   = unpack_32_le(hdr+12),
 153                         .export_count = unpack_32_le(hdr+20),
 154                         .import_count = unpack_32_le(hdr+28),
 155                 },
 156
 157                 .name_offset   = unpack_32_le(hdr+16),
 158                 .export_offset = unpack_32_le(hdr+24),
 159                 .import_offset = unpack_32_le(hdr+32),
 160         };
 161
 162         return pkg;
 163 }
 164
 165 static int pkg_init_guid(struct upkg_priv *pkg)
 166 {
 167         const struct upkg_file_ops *fops = pkg->fops;
 168         size_t rc;
 169
 170         if (pkg->pub.version < 68) {
 171                 unsigned long heritage_count, heritage_offset;
 172                 unsigned char buf[8];
 173
 174                 rc = fops->read(buf, sizeof buf, pkg->f);
 175                 if (rc < 8)
 176                         return -1;
 177
 178                 heritage_count  = unpack_32_le(buf+0);
 179                 heritage_offset = unpack_32_le(buf+4);
 180
 181                 if (heritage_count == 0)
 182                         return -1;
 183                 if (fops->seek(pkg->f, heritage_offset, SEEK_SET) != 0)
 184                         return -1;
 185         }
 186
 187         rc = fops->read(pkg->pub.guid, 16, pkg->f);
 188         if (rc < 16)
 189                 return -1;
 190
 191         return 0;
 192 }
 193
 194 static int pkg_init_names(struct upkg_priv *pkg)
 195 {
 196         const struct upkg_file_ops *fops = pkg->fops;
 197         void *f = pkg->f;
 198
 199         size_t rc, len, nbuf = 0;
 200         unsigned long index = 0;
 201         unsigned char buf[512];
 202
 203         if (fops->seek(f, pkg->name_offset, SEEK_SET) != 0)
 204                 return -1;
 205
 206         pkg->names = malloc(pkg->pub.name_count * sizeof *pkg->names);
 207         if (!pkg->names)
 208                 return -1;
 209
 210         while (index < pkg->pub.name_count) {
 211                 struct upkg_name *name = &pkg->names[index];
 212
 213                 /* Read some data into buffer. */
 214                 if (!fops->eof(pkg->f)) {
 215                         rc = fops->read(buf+nbuf, sizeof buf-nbuf, f);
 216                         if (rc == 0 && nbuf == 0)
 217                                 goto err;
 218                         nbuf += rc;
 219                 }
 220
 221                 if (pkg->pub.version >= 64) {
 222                         len = buf[0];
 223                         if (nbuf <= len + 4 || buf[len])
 224                                 goto err;
 225                         name->name = malloc(len);
 226                         if (!name->name)
 227                                 goto err;
 228                         memcpy(name->name, buf+1, len);
 229                         name->flags = unpack_32_le(buf+len+1);
 230                         len += 4;
 231
 232                         nbuf -= len + 1;
 233                         memmove(buf, buf+len+1, nbuf);
 234                         index++;
 235                 } else {
 236                         unsigned char *c = memchr(buf, 0, nbuf);
 237                         if (!c || nbuf <= c - buf + 5)
 238                                 goto err;
 239                         len = c - buf + 1;
 240                         name->name = malloc(len);
 241                         if (!name->name)
 242                                 goto err;
 243                         memcpy(name->name, buf, len);
 244                         name->flags = unpack_32_le(buf+len);
 245                         len += 4;
 246
 247                         nbuf -= len;
 248                         memmove(buf, buf+len, nbuf);
 249                         index++;
 250                 }
 251         }
 252
 253         return 0;
 254 err:
 255         for (unsigned i = 0; i < index; i++)
 256                 free(pkg->names[i].name);
 257         free(pkg->names);
 258         return -1;
 259 }
 260
 261 static int pkg_init_exports(struct upkg_priv *pkg)
 262 {
 263         const struct upkg_file_ops *fops = pkg->fops;
 264         void *f = pkg->f;
 265
 266         size_t rc, len, nbuf = 0;
 267         unsigned long index = 0;
 268         unsigned char buf[512];
 269
 270         if (fops->seek(f, pkg->export_offset, SEEK_SET) != 0)
 271                 return -1;
 272
 273         pkg->exports = malloc(pkg->pub.export_count * sizeof *pkg->exports);
 274         if (!pkg->exports)
 275                 return -1;
 276
 277         while (index < pkg->pub.export_count) {
 278                 struct upkg_export_priv *export = &pkg->exports[index];
 279                 long tmp;
 280
 281                 /* Read some data into buffer. */
 282                 if (!fops->eof(pkg->f)) {
 283                         rc = fops->read(buf+nbuf, sizeof buf-nbuf, f);
 284                         if (rc == 0 && nbuf == 0)
 285                                 goto err;
 286                         nbuf += rc;
 287                 }
 288
 289                 len = 0;
 290                 rc = upkg_decode_index(&export->class, buf+len, nbuf-len);
 291                 if (rc == 0) goto err;
 292                 len += rc;
 293
 294                 rc = upkg_decode_index(&export->super, buf+len, nbuf-len);
 295                 if (rc == 0) goto err;
 296                 len += rc;
 297
 298                 if (nbuf-len < 4) goto err;
 299                 export->pub.package = unpack_s32_le(buf+len);
 300                 len += 4;
 301
 302                 rc = upkg_decode_index(&tmp, buf+len, nbuf-len);
 303                 if (rc == 0 || tmp < 0 || tmp >= pkg->pub.name_count) goto err;
 304                 export->pub.name = pkg->names[tmp].name;
 305                 len += rc;
 306
 307                 if (nbuf-len < 4) goto err;
 308                 export->pub.flags = unpack_32_le(buf+len);
 309                 len += 4;
 310
 311                 rc = upkg_decode_index(&tmp, buf+len, nbuf-len);
 312                 if (rc == 0 || tmp < 0) goto err;
 313                 export->size = tmp;
 314                 len += rc;
 315
 316                 if (export->size) {
 317                         rc = upkg_decode_index(&tmp, buf+len, nbuf-len);
 318                         if (rc == 0 || tmp < 0) goto err;
 319                         export->offset = tmp;
 320                         len += rc;
 321                 }
 322
 323                 nbuf -= len;
 324                 memmove(buf, buf+len, nbuf);
 325                 index++;
 326         }
 327
 328         return 0;
 329 err:
 330         free(pkg->exports);
 331         return -1;
 332 }
 333
 334 static int pkg_init_imports(struct upkg_priv *pkg)
 335 {
 336         const struct upkg_file_ops *fops = pkg->fops;
 337         void *f = pkg->f;
 338
 339         size_t rc, len, nbuf = 0;
 340         unsigned long index = 0;
 341         unsigned char buf[512];
 342
 343         if (fops->seek(f, pkg->import_offset, SEEK_SET) != 0)
 344                 return -1;
 345
 346         pkg->imports = malloc(pkg->pub.import_count * sizeof *pkg->imports);
 347         if (!pkg->imports)
 348                 return -1;
 349
 350         while (index < pkg->pub.import_count) {
 351                 struct upkg_import *import = &pkg->imports[index];
 352                 long tmp;
 353
 354                 /* Read some data into buffer. */
 355                 if (!fops->eof(pkg->f)) {
 356                         rc = fops->read(buf+nbuf, sizeof buf-nbuf, f);
 357                         if (rc == 0 && nbuf == 0)
 358                                 goto err;
 359                         nbuf += rc;
 360                 }
 361
 362                 len = 0;
 363                 rc = upkg_decode_index(&tmp, buf+len, nbuf-len);
 364                 if (rc == 0 || len >= pkg->pub.name_count) goto err;
 365                 import->class_package = pkg->names[tmp].name;
 366                 len += rc;
 367
 368                 rc = upkg_decode_index(&tmp, buf+len, nbuf-len);
 369                 if (rc == 0 || len >= pkg->pub.name_count) goto err;
 370                 import->class_name = pkg->names[tmp].name;
 371                 len += rc;
 372
 373                 if (nbuf-len < 4) goto err;
 374                 import->package = unpack_s32_le(buf+len);
 375                 len += 4;
 376
 377                 rc = upkg_decode_index(&tmp, buf+len, nbuf-len);
 378                 if (rc == 0 || len >= pkg->pub.name_count) goto err;
 379                 import->object_name = pkg->names[tmp].name;
 380                 len += rc;
 381
 382                 nbuf -= len;
 383                 memmove(buf, buf+len, nbuf);
 384                 index++;
 385         }
 386
 387         return 0;
 388 err:
 389         free(pkg->imports);
 390         return -1;
 391 }
 392
 393 struct upkg *upkg_open(void *f, const struct upkg_file_ops *fops,
 394                        int (*destructor)(void *handle))
 395 {
 396         unsigned char hdr_buf[UPKG_HDR_SIZE];
 397         struct upkg_priv *pkg;
 398
 399         if (fops->read(hdr_buf, sizeof hdr_buf, f) != sizeof hdr_buf) {
 400                 return NULL;
 401         }
 402         if (unpack_32_le(hdr_buf) != UPKG_HDR_MAGIC) {
 403                 return NULL;
 404         }
 405
 406         /* Initialize package structure. */
 407         pkg = init_upkg(hdr_buf);
 408         if (!pkg) {
 409                 return NULL;
 410         }
 411         pkg->fops = fops;
 412         pkg->dtor = destructor;
 413         pkg->f    = f;
 414
 415         if (pkg_init_guid(pkg) != 0) {
 416                 goto err1;
 417         }
 418
 419         if (pkg_init_names(pkg) != 0) {
 420                 goto err1;
 421         }
 422
 423         if (pkg_init_exports(pkg) != 0) {
 424                 goto err2;
 425         }
 426
 427         if (pkg_init_imports(pkg) != 0) {
 428                 goto err3;
 429         }
 430
 431         return &pkg->pub;
 432 err3:
 433         free(pkg->exports);
 434 err2:
 435         for (unsigned i = 0; i < pkg->pub.name_count; i++)
 436                 free(pkg->names[i].name);
 437         free(pkg->names);
 438 err1:
 439         free(pkg);
 440         return NULL;
 441 }
 442
 443 struct upkg *upkg_fopen(const char *path)
 444 {
 445         struct upkg *pkg;
 446         FILE *f;
 447
 448         f = fopen(path, "rb");
 449         if (!f) {
 450                 return NULL;
 451         }
 452
 453         pkg = upkg_open(f, &upkg_default_fops, file_close);
 454         if (!pkg) {
 455                 fclose(f);
 456         }
 457
 458         return pkg;
 459 }
 460
 461 int upkg_close(struct upkg *pub)
 462 {
 463         struct upkg_priv *pkg = (struct upkg_priv *)pub;
 464         int rc = 0;
 465
 466         if (pkg->dtor) {
 467                 rc = pkg->dtor(pkg->f);
 468         }
 469
 470         for (unsigned i = 0; i < pkg->pub.name_count; i++) {
 471                 free(pkg->names[i].name);
 472         }
 473
 474         free(pkg->imports);
 475         free(pkg->exports);
 476         free(pkg->names);
 477         free(pkg);
 478
 479         return rc;
 480 }
 481
 482 const char *upkg_get_name(struct upkg *pub, unsigned long idx)
 483 {
 484         struct upkg_priv *pkg = (struct upkg_priv *)pub;
 485
 486         if (idx >= pkg->pub.name_count)
 487                 return 0;
 488         return pkg->names[idx].name;
 489 }
 490
 491 long upkg_export_find(struct upkg *pub, long parent, const char *name)
 492 {
 493         struct upkg_priv *pkg = (struct upkg_priv *)pub;
 494
 495         /* This only makes sense if the assertion below is not violated. */
 496         long package = parent < 0 ? 0 : parent + 1;
 497
 498         for (unsigned long i = 0; i < pkg->pub.export_count; i++) {
 499                 struct upkg_export_priv *e = &pkg->exports[i];
 500
 501                 /* Assertion: an object's package is an export. */
 502                 format_assert(e->pub.package >= 0, continue);
 503                 if (e->pub.package == package
 504                     && strcmp(e->pub.name, name) == 0) {
 505                         return i;
 506                 }
 507         }
 508
 509         return -1;
 510 }
 511
 512 const struct upkg_export *upkg_get_export(struct upkg *pub, unsigned long idx)
 513 {
 514         struct upkg_priv *pkg = (struct upkg_priv *)pub;
 515
 516         if (idx < pkg->pub.export_count)
 517                 return &pkg->exports[idx].pub;
 518         return NULL;
 519 }
 520
 521 const char *upkg_export_class(struct upkg *pub, unsigned long idx,
 522                               const char **package)
 523 {
 524         struct upkg_priv *pkg = (struct upkg_priv *)pub;
 525         struct upkg_export_priv *export;
 526         struct upkg_import *iclass, *ipackage;
 527         unsigned long pkg_idx;
 528
 529         if (idx >= pkg->pub.export_count)
 530                 return NULL;
 531
 532         export = &pkg->exports[idx];
 533
 534         /* Assumption: class references are always imports. */
 535         format_assert(export->class <= 0, return NULL);
 536
 537         /* Get the class. */
 538         if (export->class == 0) {
 539                 if (package) *package = "Core";
 540                 return "Class";
 541         }
 542
 543         pkg_idx = -(export->class + 1);
 544         if (pkg_idx >= pkg->pub.import_count)
 545                 return NULL;
 546         iclass = &pkg->imports[pkg_idx];
 547
 548         /* Assumption: class references are always Core.Class. */
 549         format_assert(!strcmp(iclass->class_package, "Core"), return NULL);
 550         format_assert(!strcmp(iclass->class_name, "Class"), return NULL);
 551
 552         /* Assumption: package references are always imports. */
 553         format_assert(iclass->package <= 0, return NULL);
 554
 555         /* Get the package. */
 556         pkg_idx = -(iclass->package + 1);
 557         if (pkg_idx >= pkg->pub.import_count)
 558                 return NULL;
 559         ipackage = &pkg->imports[pkg_idx];
 560
 561         /* Assumption: package references are always Core.Package. */
 562         format_assert(!strcmp(ipackage->class_package, "Core"), return NULL);
 563         format_assert(!strcmp(ipackage->class_name, "Package"), return NULL);
 564
 565         if (package) *package = ipackage->object_name;
 566         return iclass->object_name;
 567 }
 568
 569 struct upkg_file *upkg_export_open(struct upkg *pub, unsigned long idx)
 570 {
 571         struct upkg_priv *pkg = (struct upkg_priv *)pub;
 572         struct upkg_file *f;
 573
 574         if (idx >= pkg->pub.export_count)
 575                 return NULL;
 576
 577         f = malloc(sizeof *f);
 578         if (f == NULL)
 579                 return NULL;
 580
 581         *f = (struct upkg_file) {
 582                 .pkg  = pkg,
 583                 .base = pkg->exports[idx].offset,
 584                 .len  = pkg->exports[idx].size,
 585                 .name = pkg->exports[idx].pub.name,
 586         };
 587
 588         return f;
 589 }
 590
 591 void upkg_export_close(struct upkg_file *f)
 592 {
 593         if (f->pkg->last_file == f)
 594                 f->pkg->last_file = NULL;
 595         free(f);
 596 }
 597
 598 long upkg_export_tell(struct upkg_file *f)
 599 {
 600         return f->offset;
 601 }
 602
 603 int upkg_export_seek(struct upkg_file *f, long offset, int whence)
 604 {
 605         const struct upkg_file_ops *fops = f->pkg->fops;
 606         int rc = EOF;
 607
 608         switch (whence) {
 609         case SEEK_CUR:
 610                 offset = f->offset + offset;
 611         case SEEK_SET:
 612                 if (offset < 0 || offset > f->len)
 613                         return EOF;
 614                 rc = fops->seek(f->pkg->f, f->base + offset, SEEK_SET);
 615                 break;
 616         case SEEK_END:
 617                 offset = -offset;
 618                 if (offset < 0 || offset > f->len)
 619                         return EOF;
 620                 offset = f->len - offset;
 621                 rc = fops->seek(f->pkg->f, f->base + offset, SEEK_SET);
 622                 break;
 623         }
 624
 625         if (rc == 0) {
 626                 f->pkg->last_file = f;
 627                 f->offset = offset;
 628                 f->eof = 0;
 629         } else if (f->pkg->last_file == f) {
 630                 f->pkg->last_file = NULL;
 631         }
 632
 633         return rc;
 634 }
 635
 636 size_t upkg_export_read(struct upkg_file *f, void *buf, size_t n)
 637 {
 638         const struct upkg_file_ops *fops = f->pkg->fops;
 639         size_t want = MIN(n, f->len - f->offset);
 640         size_t rc;
 641
 642         if (want == 0) {
 643                 return 0;
 644         }
 645
 646         if (f != f->pkg->last_file) {
 647                 if (fops->seek(f->pkg->f, f->base + f->offset, SEEK_SET))
 648                         return 0;
 649         }
 650
 651         rc = fops->read(buf, want, f->pkg->f);
 652         f->offset += rc;
 653
 654         if (want < n || (rc < want && fops->eof(f->pkg->f)))
 655                 f->eof = 1;
 656         return rc;
 657 }