1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339
|
/*
* Extract VBA source code for component MS Office Documents
*
* Copyright (C) 2007-2013 Sourcefire, Inc.
*
* Authors: Trog, Nigel Horne
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301, USA.
*/
#if HAVE_CONFIG_H
#include "clamav-config.h"
#endif
#include <stdio.h>
#include <string.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <fcntl.h>
#include <stdlib.h>
#include <ctype.h>
#include <zlib.h>
#include "clamav.h"
#include "others.h"
#include "scanners.h"
#include "vba_extract.h"
#ifdef CL_DEBUG
#include "mbox.h"
#endif
#include "blob.h"
#ifdef HAVE_JSON
#include "json.h"
#endif
#define PPT_LZW_BUFFSIZE 8192
#define VBA_COMPRESSION_WINDOW 4096
#define MIDDLE_SIZE 20
#define MAX_VBA_COUNT 1000 /* If there's more than 1000 macros something's up! */
#ifndef HAVE_ATTRIB_PACKED
#define __attribute__(x)
#endif
/*
* VBA (Visual Basic for Applications), versions 5 and 6
*/
struct vba56_header {
unsigned char magic[2];
unsigned char version[4];
unsigned char ignore[28];
};
typedef struct {
uint32_t sig;
const char *ver;
int big_endian; /* e.g. MAC Office */
} vba_version_t;
static int skip_past_nul(int fd);
static int read_uint16(int fd, uint16_t *u, int big_endian);
static int read_uint32(int fd, uint32_t *u, int big_endian);
static int seekandread(int fd, off_t offset, int whence, void *data, size_t len);
static vba_project_t *create_vba_project(int record_count, const char *dir, struct uniq *U);
static uint16_t
vba_endian_convert_16(uint16_t value, int big_endian)
{
if (big_endian)
return (uint16_t)be16_to_host(value);
else
return le16_to_host(value);
}
/* Seems to be a duplicate of riff_endian_convert_32() */
static uint32_t
vba_endian_convert_32(uint32_t value, int big_endian)
{
if (big_endian)
return be32_to_host(value);
else
return le32_to_host(value);
}
static char *
get_unicode_name(const char *name, int size, int big_endian)
{
int i, increment;
char *newname, *ret;
if((name == NULL) || (*name == '\0') || (size <= 0))
return NULL;
newname = (char *)cli_malloc(size * 7 + 1);
if(newname == NULL) {
cli_errmsg("get_unicode_name: Unable to allocate memory for newname\n");
return NULL;
}
if((!big_endian) && (size & 0x1)) {
cli_dbgmsg("get_unicode_name: odd number of bytes %d\n", size);
--size;
}
increment = (big_endian) ? 1 : 2;
ret = newname;
for(i = 0; i < size; i += increment) {
if((!(name[i]&0x80)) && isprint(name[i])) {
*ret++ = tolower(name[i]);
} else {
if((name[i] < 10) && (name[i] >= 0)) {
*ret++ = '_';
*ret++ = (char)(name[i] + '0');
} else {
uint16_t x;
if ((i + 1) >= size)
break;
x = (uint16_t)((name[i] << 8) | name[i + 1]);
*ret++ = '_';
*ret++ = (char)('a'+((x&0xF)));
*ret++ = (char)('a'+((x>>4)&0xF));
*ret++ = (char)('a'+((x>>8)&0xF));
*ret++ = 'a';
*ret++ = 'a';
}
*ret++ = '_';
}
}
*ret = '\0';
/* Saves a lot of memory */
ret = cli_realloc(newname, (ret - newname) + 1);
return ret ? ret : newname;
}
static void vba56_test_middle(int fd)
{
char test_middle[MIDDLE_SIZE];
/* MacOffice middle */
static const uint8_t middle1_str[MIDDLE_SIZE] = {
0x00, 0x01, 0x0d, 0x45, 0x2e, 0xe1, 0xe0, 0x8f, 0x10, 0x1a,
0x85, 0x2e, 0x02, 0x60, 0x8c, 0x4d, 0x0b, 0xb4, 0x00, 0x00
};
/* MS Office middle */
static const uint8_t middle2_str[MIDDLE_SIZE] = {
0x00, 0x00, 0xe1, 0x2e, 0x45, 0x0d, 0x8f, 0xe0, 0x1a, 0x10,
0x85, 0x2e, 0x02, 0x60, 0x8c, 0x4d, 0x0b, 0xb4, 0x00, 0x00
};
if(cli_readn(fd, &test_middle, MIDDLE_SIZE) != MIDDLE_SIZE)
return;
if((memcmp(test_middle, middle1_str, MIDDLE_SIZE) != 0) &&
(memcmp(test_middle, middle2_str, MIDDLE_SIZE) != 0)) {
cli_dbgmsg("middle not found\n");
if (lseek(fd, -MIDDLE_SIZE, SEEK_CUR) == -1) {
cli_dbgmsg("vba_test_middle: call to lseek() failed\n");
return;
}
} else
cli_dbgmsg("middle found\n");
}
/* return count of valid strings found, 0 on error */
static int
vba_read_project_strings(int fd, int big_endian)
{
unsigned char *buf = NULL;
uint16_t buflen = 0;
uint16_t length = 0;
int ret = 0, getnewlength = 1;
for(;;) {
off_t offset;
char *name;
/* if no initial name length, exit */
if(getnewlength && !read_uint16(fd, &length, big_endian)) {
ret = 0;
break;
}
getnewlength = 0;
/* if too short, break */
if (length < 6) {
if (lseek(fd, -2, SEEK_CUR) == -1) {
cli_dbgmsg("vba_read_project_strings: call to lseek() has failed\n");
ret = 0;
}
break;
}
/* ensure buffer is large enough */
if(length > buflen) {
unsigned char *newbuf = (unsigned char *)cli_realloc(buf, length);
if(newbuf == NULL) {
ret = 0;
break;
}
buflen = length;
buf = newbuf;
}
/* save current offset */
offset = lseek(fd, 0, SEEK_CUR);
if (offset == -1) {
cli_dbgmsg("vba_read_project_strings: call to lseek() has failed\n");
ret = 0;
break;
}
/* if read name failed, break */
if(cli_readn(fd, buf, length) != (int)length) {
cli_dbgmsg("read name failed - rewinding\n");
if (lseek(fd, offset, SEEK_SET) == -1) {
cli_dbgmsg("call to lseek() in read name failed\n");
ret = 0;
}
break;
}
name = get_unicode_name((const char *)buf, length, big_endian);
cli_dbgmsg("length: %d, name: %s\n", length, (name) ? name : "[null]");
/* if invalid name, break */
if((name == NULL) || (memcmp("*\\", name, 2) != 0) ||
(strchr("ghcd", name[2]) == NULL)) {
/* Not a valid string, rewind */
if (lseek(fd, -(length+2), SEEK_CUR) == -1) {
cli_dbgmsg("call to lseek() after get_unicode_name has failed\n");
ret = 0;
}
free(name);
break;
}
free(name);
/* can't get length, break */
if(!read_uint16(fd, &length, big_endian)) {
break;
}
ret++;
/* continue on reasonable length value */
if ((length != 0) && (length != 65535)) {
continue;
}
/* determine offset and run middle test */
offset = lseek(fd, 10, SEEK_CUR);
if (offset == -1) {
cli_dbgmsg("call to lseek() has failed\n");
ret = 0;
break;
}
cli_dbgmsg("offset: %lu\n", (unsigned long)offset);
vba56_test_middle(fd);
getnewlength = 1;
}
free(buf);
return ret;
}
vba_project_t *
cli_vba_readdir(const char *dir, struct uniq *U, uint32_t which)
{
unsigned char *buf;
const unsigned char vba56_signature[] = { 0xcc, 0x61 };
uint16_t record_count, buflen, ffff, byte_count;
uint32_t offset;
int i, j, fd, big_endian = FALSE;
vba_project_t *vba_project;
struct vba56_header v56h;
off_t seekback;
char fullname[1024], *hash;
cli_dbgmsg("in cli_vba_readdir()\n");
if(dir == NULL)
return NULL;
/*
* _VBA_PROJECT files are embedded within office documents (OLE2)
*/
if (!uniq_get(U, "_vba_project", 12, &hash))
return NULL;
snprintf(fullname, sizeof(fullname), "%s"PATHSEP"%s_%u", dir, hash, which);
fullname[sizeof(fullname)-1] = '\0';
fd = open(fullname, O_RDONLY|O_BINARY);
if(fd == -1)
return NULL;
if(cli_readn(fd, &v56h, sizeof(struct vba56_header)) != sizeof(struct vba56_header)) {
close(fd);
return NULL;
}
if (memcmp(v56h.magic, vba56_signature, sizeof(v56h.magic)) != 0) {
close(fd);
return NULL;
}
i = vba_read_project_strings(fd, TRUE);
if ((seekback = lseek(fd, 0, SEEK_CUR)) == -1) {
cli_dbgmsg("vba_readdir: lseek() failed. Unable to guess VBA type\n");
close(fd);
return NULL;
}
if (lseek(fd, sizeof(struct vba56_header), SEEK_SET) == -1) {
cli_dbgmsg("vba_readdir: lseek() failed. Unable to guess VBA type\n");
close(fd);
return NULL;
}
j = vba_read_project_strings(fd, FALSE);
if(!i && !j) {
close(fd);
cli_dbgmsg("vba_readdir: Unable to guess VBA type\n");
return NULL;
}
if (i > j) {
big_endian = TRUE;
if (lseek(fd, seekback, SEEK_SET) == -1) {
cli_dbgmsg("vba_readdir: call to lseek() while guessing big-endian has failed\n");
close(fd);
return NULL;
}
cli_dbgmsg("vba_readdir: Guessing big-endian\n");
} else {
cli_dbgmsg("vba_readdir: Guessing little-endian\n");
}
/* junk some more stuff */
do
if (cli_readn(fd, &ffff, 2) != 2) {
close(fd);
return NULL;
}
while(ffff != 0xFFFF);
/* check for alignment error */
if(!seekandread(fd, -3, SEEK_CUR, &ffff, sizeof(uint16_t))) {
close(fd);
return NULL;
}
if (ffff != 0xFFFF) {
if (lseek(fd, 1, SEEK_CUR) == -1) {
cli_dbgmsg("call to lseek() while checking alignment error has failed\n");
close(fd);
return NULL;
}
}
if(!read_uint16(fd, &ffff, big_endian)) {
close(fd);
return NULL;
}
if(ffff != 0xFFFF) {
if (lseek(fd, ffff, SEEK_CUR) == -1) {
cli_dbgmsg("call to lseek() while checking alignment error has failed\n");
close(fd);
return NULL;
}
}
if(!read_uint16(fd, &ffff, big_endian)) {
close(fd);
return NULL;
}
if(ffff == 0xFFFF)
ffff = 0;
if (lseek(fd, ffff + 100, SEEK_CUR) == -1) {
cli_dbgmsg("call to lseek() failed\n");
close(fd);
return NULL;
}
if(!read_uint16(fd, &record_count, big_endian)) {
close(fd);
return NULL;
}
cli_dbgmsg("vba_readdir: VBA Record count %d\n", record_count);
if (record_count == 0) {
/* No macros, assume clean */
close(fd);
return NULL;
}
if (record_count > MAX_VBA_COUNT) {
/* Almost certainly an error */
cli_dbgmsg("vba_readdir: VBA Record count too big\n");
close(fd);
return NULL;
}
vba_project = create_vba_project(record_count, dir, U);
if(vba_project == NULL) {
close(fd);
return NULL;
}
buf = NULL;
buflen = 0;
for(i = 0; i < record_count; i++) {
uint16_t length;
char *ptr;
vba_project->colls[i] = 0;
if(!read_uint16(fd, &length, big_endian))
break;
if (length == 0) {
cli_dbgmsg("vba_readdir: zero name length\n");
break;
}
if(length > buflen) {
unsigned char *newbuf = (unsigned char *)cli_realloc(buf, length);
if(newbuf == NULL)
break;
buflen = length;
buf = newbuf;
}
if (cli_readn(fd, buf, length) != length) {
cli_dbgmsg("vba_readdir: read name failed\n");
break;
}
ptr = get_unicode_name((const char *)buf, length, big_endian);
if(ptr == NULL) break;
if (!(vba_project->colls[i]=uniq_get(U, ptr, strlen(ptr), &hash))) {
cli_dbgmsg("vba_readdir: cannot find project %s (%s)\n", ptr, hash);
free(ptr);
break;
}
cli_dbgmsg("vba_readdir: project name: %s (%s)\n", ptr, hash);
free(ptr);
vba_project->name[i] = hash;
if(!read_uint16(fd, &length, big_endian))
break;
lseek(fd, length, SEEK_CUR);
if(!read_uint16(fd, &ffff, big_endian))
break;
if (ffff == 0xFFFF) {
lseek(fd, 2, SEEK_CUR);
if(!read_uint16(fd, &ffff, big_endian))
break;
lseek(fd, ffff + 8, SEEK_CUR);
} else
lseek(fd, ffff + 10, SEEK_CUR);
if(!read_uint16(fd, &byte_count, big_endian))
break;
lseek(fd, (8 * byte_count) + 5, SEEK_CUR);
if(!read_uint32(fd, &offset, big_endian))
break;
cli_dbgmsg("vba_readdir: offset: %u\n", (unsigned int)offset);
vba_project->offset[i] = offset;
lseek(fd, 2, SEEK_CUR);
}
if(buf)
free(buf);
close(fd);
if(i < record_count) {
free(vba_project->name);
free(vba_project->colls);
free(vba_project->dir);
free(vba_project->offset);
free(vba_project);
return NULL;
}
return vba_project;
}
unsigned char *
cli_vba_inflate(int fd, off_t offset, int *size)
{
unsigned int pos, shift, mask, distance, clean;
uint8_t flag;
uint16_t token;
blob *b;
unsigned char buffer[VBA_COMPRESSION_WINDOW];
if(fd < 0)
return NULL;
b = blobCreate();
if(b == NULL)
return NULL;
memset(buffer, 0, sizeof(buffer));
lseek(fd, offset+3, SEEK_SET); /* 1byte ?? , 2byte length ?? */
clean = TRUE;
pos = 0;
while (cli_readn(fd, &flag, 1) == 1) {
for(mask = 1; mask < 0x100; mask<<=1) {
unsigned int winpos = pos % VBA_COMPRESSION_WINDOW;
if (flag & mask) {
uint16_t len;
unsigned int srcpos;
if(!read_uint16(fd, &token, FALSE)) {
blobDestroy(b);
if(size)
*size = 0;
return NULL;
}
shift = 12 - (winpos > 0x10)
- (winpos > 0x20)
- (winpos > 0x40)
- (winpos > 0x80)
- (winpos > 0x100)
- (winpos > 0x200)
- (winpos > 0x400)
- (winpos > 0x800);
len = (uint16_t)((token & ((1 << shift) - 1)) + 3);
distance = token >> shift;
srcpos = pos - distance - 1;
if((((srcpos + len) % VBA_COMPRESSION_WINDOW) < winpos) &&
((winpos + len) < VBA_COMPRESSION_WINDOW) &&
(((srcpos % VBA_COMPRESSION_WINDOW) + len) < VBA_COMPRESSION_WINDOW) &&
(len <= VBA_COMPRESSION_WINDOW)) {
srcpos %= VBA_COMPRESSION_WINDOW;
memcpy(&buffer[winpos], &buffer[srcpos],
len);
pos += len;
} else
while(len-- > 0) {
srcpos = (pos - distance - 1) % VBA_COMPRESSION_WINDOW;
buffer[pos++ % VBA_COMPRESSION_WINDOW] = buffer[srcpos];
}
} else {
if((pos != 0) && (winpos == 0) && clean) {
if (cli_readn(fd, &token, 2) != 2) {
blobDestroy(b);
if(size)
*size = 0;
return NULL;
}
(void)blobAddData(b, buffer, VBA_COMPRESSION_WINDOW);
clean = FALSE;
break;
}
if(cli_readn(fd, &buffer[winpos], 1) == 1)
pos++;
}
clean = TRUE;
}
}
if(blobAddData(b, buffer, pos%VBA_COMPRESSION_WINDOW) < 0) {
blobDestroy(b);
if(size)
*size = 0;
return NULL;
}
if(size)
*size = (int)blobGetDataSize(b);
return (unsigned char *)blobToMem(b);
}
/*
* See also cli_filecopy()
*/
static void
ole_copy_file_data(int s, int d, uint32_t len)
{
unsigned char data[FILEBUFF];
while(len > 0) {
int todo = MIN(sizeof(data), len);
if(cli_readn(s, data, (unsigned int)todo) != todo)
break;
if(cli_writen(d, data, (unsigned int)todo) != todo)
break;
len -= todo;
}
}
int
cli_scan_ole10(int fd, cli_ctx *ctx)
{
int ofd, ret;
uint32_t object_size;
STATBUF statbuf;
char *fullname;
if(fd < 0)
return CL_CLEAN;
lseek(fd, 0, SEEK_SET);
if(!read_uint32(fd, &object_size, FALSE))
return CL_CLEAN;
if(FSTAT(fd, &statbuf) == -1)
return CL_ESTAT;
if ((statbuf.st_size - object_size) >= 4) {
/* Probably the OLE type id */
if (lseek(fd, 2, SEEK_CUR) == -1) {
return CL_CLEAN;
}
/* Attachment name */
if(!skip_past_nul(fd))
return CL_CLEAN;
/* Attachment full path */
if(!skip_past_nul(fd))
return CL_CLEAN;
/* ??? */
if(lseek(fd, 8, SEEK_CUR) == -1)
return CL_CLEAN;
/* Attachment full path */
if(!skip_past_nul(fd))
return CL_CLEAN;
if(!read_uint32(fd, &object_size, FALSE))
return CL_CLEAN;
}
if(!(fullname = cli_gentemp(ctx ? ctx->engine->tmpdir : NULL))) {
return CL_EMEM;
}
ofd = open(fullname, O_RDWR|O_CREAT|O_TRUNC|O_BINARY|O_EXCL,
S_IWUSR|S_IRUSR);
if (ofd < 0) {
cli_warnmsg("cli_decode_ole_object: can't create %s\n", fullname);
free(fullname);
return CL_ECREAT;
}
cli_dbgmsg("cli_decode_ole_object: decoding to %s\n", fullname);
ole_copy_file_data(fd, ofd, object_size);
lseek(ofd, 0, SEEK_SET);
ret = cli_magic_scandesc(ofd, ctx);
close(ofd);
if(ctx && !ctx->engine->keeptmp)
if (cli_unlink(fullname))
ret = CL_EUNLINK;
free(fullname);
return ret;
}
/*
* Powerpoint files
*/
typedef struct {
uint16_t type;
uint32_t length;
} atom_header_t;
static int
ppt_read_atom_header(int fd, atom_header_t *atom_header)
{
uint16_t v;
struct ppt_header {
uint16_t ver;
uint16_t type;
uint32_t length;
} h;
cli_dbgmsg("in ppt_read_atom_header\n");
if(cli_readn(fd, &h, sizeof(struct ppt_header)) != sizeof(struct ppt_header)) {
cli_dbgmsg("read ppt_header failed\n");
return FALSE;
}
v = vba_endian_convert_16(h.ver, FALSE);
cli_dbgmsg("\tversion: 0x%.2x\n", v & 0xF);
cli_dbgmsg("\tinstance: 0x%.2x\n", v >> 4);
atom_header->type = vba_endian_convert_16(h.type, FALSE);
cli_dbgmsg("\ttype: 0x%.4x\n", atom_header->type);
atom_header->length = vba_endian_convert_32(h.length, FALSE);
cli_dbgmsg("\tlength: 0x%.8x\n", (int)atom_header->length);
return TRUE;
}
/*
* TODO: combine shared code with flatedecode() or cli_unzip_single()
* Needs cli_unzip_single to have a "length" argument
*/
static int
ppt_unlzw(const char *dir, int fd, uint32_t length)
{
int ofd;
z_stream stream;
unsigned char inbuff[PPT_LZW_BUFFSIZE], outbuff[PPT_LZW_BUFFSIZE];
char fullname[NAME_MAX + 1];
snprintf(fullname, sizeof(fullname) - 1, "%s"PATHSEP"ppt%.8lx.doc",
dir, (long)lseek(fd, 0L, SEEK_CUR));
ofd = open(fullname, O_WRONLY|O_CREAT|O_TRUNC|O_BINARY|O_EXCL,
S_IWUSR|S_IRUSR);
if (ofd == -1) {
cli_warnmsg("ppt_unlzw: can't create %s\n", fullname);
return FALSE;
}
stream.zalloc = Z_NULL;
stream.zfree = Z_NULL;
stream.opaque = (void *)NULL;
stream.next_in = (Bytef *)inbuff;
stream.next_out = outbuff;
stream.avail_out = sizeof(outbuff);
stream.avail_in = MIN(length, PPT_LZW_BUFFSIZE);
if(cli_readn(fd, inbuff, stream.avail_in) != (int)stream.avail_in) {
close(ofd);
cli_unlink(fullname);
return FALSE;
}
length -= stream.avail_in;
if(inflateInit(&stream) != Z_OK) {
close(ofd);
cli_unlink(fullname);
cli_warnmsg("ppt_unlzw: inflateInit failed\n");
return FALSE;
}
do {
if (stream.avail_out == 0) {
if (cli_writen(ofd, outbuff, PPT_LZW_BUFFSIZE)
!= PPT_LZW_BUFFSIZE) {
close(ofd);
inflateEnd(&stream);
return FALSE;
}
stream.next_out = outbuff;
stream.avail_out = PPT_LZW_BUFFSIZE;
}
if (stream.avail_in == 0) {
stream.next_in = inbuff;
stream.avail_in = MIN(length, PPT_LZW_BUFFSIZE);
if (cli_readn(fd, inbuff, stream.avail_in) != (int)stream.avail_in) {
close(ofd);
inflateEnd(&stream);
return FALSE;
}
length -= stream.avail_in;
}
} while(inflate(&stream, Z_NO_FLUSH) == Z_OK);
if (cli_writen(ofd, outbuff, PPT_LZW_BUFFSIZE-stream.avail_out) != (int)(PPT_LZW_BUFFSIZE-stream.avail_out)) {
close(ofd);
inflateEnd(&stream);
return FALSE;
}
close(ofd);
return inflateEnd(&stream) == Z_OK;
}
static const char *
ppt_stream_iter(int fd, const char *dir)
{
atom_header_t atom_header;
while(ppt_read_atom_header(fd, &atom_header)) {
if(atom_header.length == 0)
return NULL;
if(atom_header.type == 0x1011) {
uint32_t length;
/* Skip over ID */
if(lseek(fd, sizeof(uint32_t), SEEK_CUR) == -1) {
cli_dbgmsg("ppt_stream_iter: seek failed\n");
return NULL;
}
length = atom_header.length - 4;
cli_dbgmsg("length: %d\n", (int)length);
if (!ppt_unlzw(dir, fd, length)) {
cli_dbgmsg("ppt_unlzw failed\n");
return NULL;
}
} else {
off_t offset = lseek(fd, 0, SEEK_CUR);
/* Check we don't wrap */
if ((offset + (off_t)atom_header.length) < offset) {
break;
}
offset += atom_header.length;
if (lseek(fd, offset, SEEK_SET) != offset) {
break;
}
}
}
return dir;
}
char *
cli_ppt_vba_read(int ifd, cli_ctx *ctx)
{
char *dir;
const char *ret;
/* Create a directory to store the extracted OLE2 objects */
dir = cli_gentemp(ctx ? ctx->engine->tmpdir : NULL);
if(dir == NULL)
return NULL;
if(mkdir(dir, 0700)) {
cli_errmsg("cli_ppt_vba_read: Can't create temporary directory %s\n", dir);
free(dir);
return NULL;
}
ret = ppt_stream_iter(ifd, dir);
if(ret == NULL) {
cli_rmdirs(dir);
free(dir);
return NULL;
}
return dir;
}
/*
* Word 6 macros
*/
typedef struct {
unsigned char unused[12];
uint32_t macro_offset;
uint32_t macro_len;
} mso_fib_t;
typedef struct macro_entry_tag {
uint32_t len;
uint32_t offset;
unsigned char key;
} macro_entry_t;
typedef struct macro_info_tag {
struct macro_entry_tag *entries;
uint16_t count;
} macro_info_t;
static int
word_read_fib(int fd, mso_fib_t *fib)
{
struct {
uint32_t offset;
uint32_t len;
} macro_details;
if(!seekandread(fd, 0x118, SEEK_SET, ¯o_details, sizeof(macro_details))) {
cli_dbgmsg("read word_fib failed\n");
return FALSE;
}
fib->macro_offset = vba_endian_convert_32(macro_details.offset, FALSE);
fib->macro_len = vba_endian_convert_32(macro_details.len, FALSE);
return TRUE;
}
static int
word_read_macro_entry(int fd, macro_info_t *macro_info)
{
int msize;
int count = macro_info->count;
macro_entry_t *macro_entry;
#ifdef HAVE_PRAGMA_PACK
#pragma pack(1)
#endif
#ifdef HAVE_PRAGMA_PACK_HPPA
#pragma pack 1
#endif
struct macro {
unsigned char version;
unsigned char key;
unsigned char ignore[10];
uint32_t len __attribute__ ((packed));
uint32_t state __attribute__ ((packed));
uint32_t offset __attribute__ ((packed));
} *m;
const struct macro *n;
#ifdef HAVE_PRAGMA_PACK
#pragma pack()
#endif
#ifdef HAVE_PRAGMA_PACK_HPPA
#pragma pack
#endif
if(count == 0)
return TRUE;
msize = count * sizeof(struct macro);
m = cli_malloc(msize);
if(m == NULL) {
cli_errmsg("word_read_macro_entry: Unable to allocate memory for 'm'\n");
return FALSE;
}
if(cli_readn(fd, m, msize) != msize) {
free(m);
cli_warnmsg("read %d macro_entries failed\n", count);
return FALSE;
}
macro_entry = macro_info->entries;
n = m;
do {
macro_entry->key = n->key;
macro_entry->len = vba_endian_convert_32(n->len, FALSE);
macro_entry->offset = vba_endian_convert_32(n->offset, FALSE);
macro_entry++;
n++;
} while(--count > 0);
free(m);
return TRUE;
}
static macro_info_t *
word_read_macro_info(int fd, macro_info_t *macro_info)
{
if(!read_uint16(fd, ¯o_info->count, FALSE)) {
cli_dbgmsg("read macro_info failed\n");
macro_info->count = 0;
return NULL;
}
cli_dbgmsg("macro count: %d\n", macro_info->count);
if(macro_info->count == 0)
return NULL;
macro_info->entries = (macro_entry_t *)cli_malloc(sizeof(macro_entry_t) * macro_info->count);
if(macro_info->entries == NULL) {
macro_info->count = 0;
cli_errmsg("word_read_macro_info: Unable to allocate memory for macro_info->entries\n");
return NULL;
}
if(!word_read_macro_entry(fd, macro_info)) {
free(macro_info->entries);
macro_info->count = 0;
return NULL;
}
return macro_info;
}
static int
word_skip_oxo3(int fd)
{
uint8_t count;
if (cli_readn(fd, &count, 1) != 1) {
cli_dbgmsg("read oxo3 record1 failed\n");
return FALSE;
}
cli_dbgmsg("oxo3 records1: %d\n", count);
if(!seekandread(fd, count * 14, SEEK_CUR, &count, 1)) {
cli_dbgmsg("read oxo3 record2 failed\n");
return FALSE;
}
if(count == 0) {
uint8_t twobytes[2];
if(cli_readn(fd, twobytes, 2) != 2) {
cli_dbgmsg("read oxo3 failed\n");
return FALSE;
}
if(twobytes[0] != 2) {
lseek(fd, -2, SEEK_CUR);
return TRUE;
}
count = twobytes[1];
}
if(count > 0)
if (lseek(fd, (count*4)+1, SEEK_CUR) == -1) {
cli_dbgmsg("lseek oxo3 failed\n");
return FALSE;
}
cli_dbgmsg("oxo3 records2: %d\n", count);
return TRUE;
}
static int
word_skip_menu_info(int fd)
{
uint16_t count;
if(!read_uint16(fd, &count, FALSE)) {
cli_dbgmsg("read menu_info failed\n");
return FALSE;
}
cli_dbgmsg("menu_info count: %d\n", count);
if(count)
if(lseek(fd, count * 12, SEEK_CUR) == -1)
return FALSE;
return TRUE;
}
static int
word_skip_macro_extnames(int fd)
{
int is_unicode, nbytes;
int16_t size;
if(!read_uint16(fd, (uint16_t *)&size, FALSE)) {
cli_dbgmsg("read macro_extnames failed\n");
return FALSE;
}
if (size == -1) { /* Unicode flag */
if(!read_uint16(fd, (uint16_t *)&size, FALSE)) {
cli_dbgmsg("read macro_extnames failed\n");
return FALSE;
}
is_unicode = 1;
} else
is_unicode = 0;
cli_dbgmsg("ext names size: 0x%x\n", size);
nbytes = size;
while(nbytes > 0) {
uint8_t length;
off_t offset;
if (cli_readn(fd, &length, 1) != 1) {
cli_dbgmsg("read macro_extnames failed\n");
return FALSE;
}
if(is_unicode)
offset = (off_t)length * 2 + 1;
else
offset = (off_t)length;
/* ignore numref as well */
if(lseek(fd, offset + sizeof(uint16_t), SEEK_CUR) == -1) {
cli_dbgmsg("read macro_extnames failed to seek\n");
return FALSE;
}
nbytes -= size;
}
return TRUE;
}
static int
word_skip_macro_intnames(int fd)
{
uint16_t count;
if(!read_uint16(fd, &count, FALSE)) {
cli_dbgmsg("read macro_intnames failed\n");
return FALSE;
}
cli_dbgmsg("intnames count: %u\n", (unsigned int)count);
while(count-- > 0) {
uint8_t length;
/* id */
if(!seekandread(fd, sizeof(uint16_t), SEEK_CUR, &length, sizeof(uint8_t))) {
cli_dbgmsg("skip_macro_intnames failed\n");
return FALSE;
}
/* Internal name, plus one byte of unknown data */
if(lseek(fd, length + 1, SEEK_CUR) == -1) {
cli_dbgmsg("skip_macro_intnames failed\n");
return FALSE;
}
}
return TRUE;
}
vba_project_t *
cli_wm_readdir(int fd)
{
int done;
off_t end_offset;
unsigned char info_id;
macro_info_t macro_info;
vba_project_t *vba_project;
mso_fib_t fib;
if (!word_read_fib(fd, &fib))
return NULL;
if(fib.macro_len == 0) {
cli_dbgmsg("wm_readdir: No macros detected\n");
/* Must be clean */
return NULL;
}
cli_dbgmsg("wm_readdir: macro offset: 0x%.4x\n", (int)fib.macro_offset);
cli_dbgmsg("wm_readdir: macro len: 0x%.4x\n\n", (int)fib.macro_len);
/* Go one past the start to ignore start_id */
if (lseek(fd, fib.macro_offset + 1, SEEK_SET) != (off_t)(fib.macro_offset + 1)) {
cli_dbgmsg("wm_readdir: lseek macro_offset failed\n");
return NULL;
}
end_offset = fib.macro_offset + fib.macro_len;
done = FALSE;
macro_info.entries = NULL;
macro_info.count = 0;
while((lseek(fd, 0, SEEK_CUR) < end_offset) && !done) {
if (cli_readn(fd, &info_id, 1) != 1) {
cli_dbgmsg("wm_readdir: read macro_info failed\n");
break;
}
switch (info_id) {
case 0x01:
if(macro_info.count)
free(macro_info.entries);
word_read_macro_info(fd, ¯o_info);
done = TRUE;
break;
case 0x03:
if(!word_skip_oxo3(fd))
done = TRUE;
break;
case 0x05:
if(!word_skip_menu_info(fd))
done = TRUE;
break;
case 0x10:
if(!word_skip_macro_extnames(fd))
done = TRUE;
break;
case 0x11:
if(!word_skip_macro_intnames(fd))
done = TRUE;
break;
case 0x40: /* end marker */
case 0x12: /* ??? */
done = TRUE;
break;
default:
cli_dbgmsg("wm_readdir: unknown type: 0x%x\n", info_id);
done = TRUE;
}
}
if(macro_info.count == 0)
return NULL;
vba_project = create_vba_project(macro_info.count, "", NULL);
if(vba_project) {
vba_project->length = (uint32_t *)cli_malloc(sizeof(uint32_t) *
macro_info.count);
vba_project->key = (unsigned char *)cli_malloc(sizeof(unsigned char) *
macro_info.count);
if((vba_project->length != NULL) &&
(vba_project->key != NULL)) {
int i;
const macro_entry_t *m = macro_info.entries;
for(i = 0; i < macro_info.count; i++) {
vba_project->offset[i] = m->offset;
vba_project->length[i] = m->len;
vba_project->key[i] = m->key;
m++;
}
} else {
cli_errmsg("cli_wm_readdir: Unable to allocate memory for vba_project\n");
free(vba_project->name);
free(vba_project->colls);
free(vba_project->dir);
free(vba_project->offset);
if(vba_project->length)
free(vba_project->length);
if(vba_project->key)
free(vba_project->key);
free(vba_project);
vba_project = NULL;
}
}
free(macro_info.entries);
return vba_project;
}
unsigned char *
cli_wm_decrypt_macro(int fd, off_t offset, uint32_t len, unsigned char key)
{
unsigned char *buff;
if(len == 0)
return NULL;
if(fd < 0)
return NULL;
buff = (unsigned char *)cli_malloc(len);
if(buff == NULL) {
cli_errmsg("cli_wm_decrypt_macro: Unable to allocate memory for buff\n");
return NULL;
}
if(!seekandread(fd, offset, SEEK_SET, buff, len)) {
free(buff);
return NULL;
}
if(key) {
unsigned char *p;
for(p = buff; p < &buff[len]; p++)
*p ^= key;
}
return buff;
}
/*
* Keep reading bytes until we reach a NUL. Returns 0 if none is found
*/
static int
skip_past_nul(int fd)
{
char *end;
char smallbuf[128];
do {
int nread = cli_readn(fd, smallbuf, sizeof(smallbuf));
if (nread <= 0)
return FALSE;
end = memchr(smallbuf, '\0', nread);
if (end) {
if (lseek(fd, 1 + (end-smallbuf) - nread, SEEK_CUR) < 0)
return FALSE;
return TRUE;
}
} while (1);
}
/*
* Read 2 bytes as a 16-bit number, host byte order. Return success or fail
*/
static int
read_uint16(int fd, uint16_t *u, int big_endian)
{
if(cli_readn(fd, u, sizeof(uint16_t)) != sizeof(uint16_t))
return FALSE;
*u = vba_endian_convert_16(*u, big_endian);
return TRUE;
}
/*
* Read 4 bytes as a 32-bit number, host byte order. Return success or fail
*/
static int
read_uint32(int fd, uint32_t *u, int big_endian)
{
if(cli_readn(fd, u, sizeof(uint32_t)) != sizeof(uint32_t))
return FALSE;
*u = vba_endian_convert_32(*u, big_endian);
return TRUE;
}
/*
* Miss some bytes then read a bit
*/
static int
seekandread(int fd, off_t offset, int whence, void *data, size_t len)
{
if(lseek(fd, offset, whence) == (off_t)-1) {
cli_dbgmsg("lseek failed\n");
return FALSE;
}
return cli_readn(fd, data, (unsigned int)len) == (int)len;
}
/*
* Create and initialise a vba_project structure
*/
static vba_project_t *
create_vba_project(int record_count, const char *dir, struct uniq *U)
{
vba_project_t *ret;
ret = (vba_project_t *) cli_malloc(sizeof(struct vba_project_tag));
if(ret == NULL) {
cli_errmsg("create_vba_project: Unable to allocate memory for vba project structure\n");
return NULL;
}
ret->name = (char **)cli_malloc(sizeof(char *) * record_count);
ret->colls = (uint32_t *)cli_malloc(sizeof(uint32_t) * record_count);
ret->dir = cli_strdup(dir);
ret->offset = (uint32_t *)cli_malloc (sizeof(uint32_t) * record_count);
if((ret->name == NULL) || (ret->dir == NULL) || (ret->offset == NULL)) {
if(ret->dir)
free(ret->dir);
if(ret->colls)
free(ret->colls);
if(ret->name)
free(ret->name);
if(ret->offset)
free(ret->offset);
free(ret);
cli_errmsg("create_vba_project: Unable to allocate memory for vba project elements\n");
return NULL;
}
ret->count = record_count;
ret->U = U;
return ret;
}
|