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1268 lines
28 KiB
1268 lines
28 KiB
/*
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* Extract VBA source code for component MS Office Documents
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*
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* Copyright (C) 2007-2008 Sourcefire, Inc.
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*
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* Authors: Trog, Nigel Horne
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
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* MA 02110-1301, USA.
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*/
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#if HAVE_CONFIG_H
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#include "clamav-config.h"
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#endif
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#include <stdio.h>
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#include <string.h>
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#ifdef HAVE_UNISTD_H
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#include <unistd.h>
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#endif
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#include <fcntl.h>
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#include <stdlib.h>
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#include <ctype.h>
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#include <zlib.h>
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#include "clamav.h"
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#include "others.h"
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#include "scanners.h"
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#include "vba_extract.h"
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#ifdef CL_DEBUG
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#include "mbox.h"
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#endif
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#include "blob.h"
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#define PPT_LZW_BUFFSIZE 8192
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#define VBA_COMPRESSION_WINDOW 4096
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#define MIDDLE_SIZE 20
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#define MAX_VBA_COUNT 1000 /* If there's more than 1000 macros something's up! */
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#ifndef HAVE_ATTRIB_PACKED
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#define __attribute__(x)
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#endif
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/*
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* VBA (Visual Basic for Applications), versions 5 and 6
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*/
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struct vba56_header {
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unsigned char magic[2];
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unsigned char version[4];
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unsigned char ignore[28];
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};
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typedef struct {
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uint32_t sig;
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const char *ver;
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int big_endian; /* e.g. MAC Office */
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} vba_version_t;
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static int skip_past_nul(int fd);
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static int read_uint16(int fd, uint16_t *u, int big_endian);
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static int read_uint32(int fd, uint32_t *u, int big_endian);
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static int seekandread(int fd, off_t offset, int whence, void *data, size_t len);
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static vba_project_t *create_vba_project(int record_count, const char *dir, struct uniq *U);
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static uint16_t
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vba_endian_convert_16(uint16_t value, int big_endian)
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{
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if (big_endian)
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return (uint16_t)be16_to_host(value);
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else
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return le16_to_host(value);
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}
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/* Seems to be a duplicate of riff_endian_convert_32() */
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static uint32_t
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vba_endian_convert_32(uint32_t value, int big_endian)
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{
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if (big_endian)
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return be32_to_host(value);
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else
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return le32_to_host(value);
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}
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static char *
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get_unicode_name(const char *name, int size, int big_endian)
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{
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int i, increment;
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char *newname, *ret;
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if((name == NULL) || (*name == '\0') || (size <= 0))
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return NULL;
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newname = (char *)cli_malloc(size * 7 + 1);
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if(newname == NULL)
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return NULL;
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if((!big_endian) && (size & 0x1)) {
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cli_dbgmsg("get_unicode_name: odd number of bytes %d\n", size);
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--size;
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}
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increment = (big_endian) ? 1 : 2;
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ret = newname;
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for(i = 0; i < size; i += increment) {
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if((!(name[i]&0x80)) && isprint(name[i])) {
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*ret++ = tolower(name[i]);
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} else {
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if((name[i] < 10) && (name[i] >= 0)) {
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*ret++ = '_';
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*ret++ = (char)(name[i] + '0');
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} else {
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const uint16_t x = (uint16_t)((name[i] << 8) | name[i + 1]);
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*ret++ = '_';
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*ret++ = (char)('a'+((x&0xF)));
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*ret++ = (char)('a'+((x>>4)&0xF));
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*ret++ = (char)('a'+((x>>8)&0xF));
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*ret++ = 'a';
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*ret++ = 'a';
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}
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*ret++ = '_';
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}
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}
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*ret = '\0';
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/* Saves a lot of memory */
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ret = cli_realloc(newname, (ret - newname) + 1);
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return ret ? ret : newname;
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}
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static void vba56_test_middle(int fd)
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{
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char test_middle[MIDDLE_SIZE];
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/* MacOffice middle */
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static const uint8_t middle1_str[MIDDLE_SIZE] = {
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0x00, 0x01, 0x0d, 0x45, 0x2e, 0xe1, 0xe0, 0x8f, 0x10, 0x1a,
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0x85, 0x2e, 0x02, 0x60, 0x8c, 0x4d, 0x0b, 0xb4, 0x00, 0x00
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};
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/* MS Office middle */
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static const uint8_t middle2_str[MIDDLE_SIZE] = {
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0x00, 0x00, 0xe1, 0x2e, 0x45, 0x0d, 0x8f, 0xe0, 0x1a, 0x10,
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0x85, 0x2e, 0x02, 0x60, 0x8c, 0x4d, 0x0b, 0xb4, 0x00, 0x00
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};
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if(cli_readn(fd, &test_middle, MIDDLE_SIZE) != MIDDLE_SIZE)
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return;
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if((memcmp(test_middle, middle1_str, MIDDLE_SIZE) != 0) &&
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(memcmp(test_middle, middle2_str, MIDDLE_SIZE) != 0)) {
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cli_dbgmsg("middle not found\n");
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lseek(fd, -MIDDLE_SIZE, SEEK_CUR);
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} else
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cli_dbgmsg("middle found\n");
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}
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static int
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vba_read_project_strings(int fd, int big_endian)
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{
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unsigned char *buf = NULL;
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uint16_t buflen = 0;
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int ret = 0;
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for(;;) {
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off_t offset;
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uint16_t length;
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char *name;
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if(!read_uint16(fd, &length, big_endian))
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break;
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if (length < 6) {
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lseek(fd, -2, SEEK_CUR);
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break;
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}
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if(length > buflen) {
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unsigned char *newbuf = (unsigned char *)cli_realloc(buf, length);
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if(newbuf == NULL) {
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if(buf)
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free(buf);
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return 0;
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}
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buflen = length;
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buf = newbuf;
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}
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offset = lseek(fd, 0, SEEK_CUR);
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if(cli_readn(fd, buf, length) != (int)length) {
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cli_dbgmsg("read name failed - rewinding\n");
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lseek(fd, offset, SEEK_SET);
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break;
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}
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name = get_unicode_name((const char *)buf, length, big_endian);
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cli_dbgmsg("length: %d, name: %s\n", length, (name) ? name : "[null]");
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if((name == NULL) || (memcmp("*\\", name, 2) != 0) ||
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(strchr("ghcd", name[2]) == NULL)) {
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/* Not a string */
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lseek(fd, -(length+2), SEEK_CUR);
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if(name)
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free(name);
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break;
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}
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free(name);
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if(!read_uint16(fd, &length, big_endian)) {
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if(buf) {
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free(buf);
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buf = NULL;
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}
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break;
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}
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ret++;
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if ((length != 0) && (length != 65535)) {
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lseek(fd, -2, SEEK_CUR);
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continue;
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}
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offset = lseek(fd, 10, SEEK_CUR);
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cli_dbgmsg("offset: %lu\n", (unsigned long)offset);
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vba56_test_middle(fd);
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}
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if(buf)
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free(buf);
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return ret;
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}
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vba_project_t *
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cli_vba_readdir(const char *dir, struct uniq *U, uint32_t which)
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{
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unsigned char *buf;
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const unsigned char vba56_signature[] = { 0xcc, 0x61 };
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uint16_t record_count, buflen, ffff, byte_count;
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uint32_t offset;
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int i, j, fd, big_endian = FALSE;
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vba_project_t *vba_project;
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struct vba56_header v56h;
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off_t seekback;
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char fullname[1024], *hash;
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cli_dbgmsg("in cli_vba_readdir()\n");
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if(dir == NULL)
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return NULL;
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/*
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* _VBA_PROJECT files are embedded within office documents (OLE2)
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*/
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if (!uniq_get(U, "_vba_project", 12, &hash))
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return NULL;
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snprintf(fullname, sizeof(fullname), "%s"PATHSEP"%s_%u", dir, hash, which);
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fullname[sizeof(fullname)-1] = '\0';
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fd = open(fullname, O_RDONLY|O_BINARY);
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if(fd == -1)
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return NULL;
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if(cli_readn(fd, &v56h, sizeof(struct vba56_header)) != sizeof(struct vba56_header)) {
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close(fd);
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return NULL;
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}
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if (memcmp(v56h.magic, vba56_signature, sizeof(v56h.magic)) != 0) {
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close(fd);
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return NULL;
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}
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i = vba_read_project_strings(fd, TRUE);
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seekback = lseek(fd, 0, SEEK_CUR);
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if (lseek(fd, sizeof(struct vba56_header), SEEK_SET) == -1) {
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close(fd);
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return NULL;
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}
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j = vba_read_project_strings(fd, FALSE);
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if(!i && !j) {
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close(fd);
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cli_dbgmsg("vba_readdir: Unable to guess VBA type\n");
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return NULL;
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}
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if (i > j) {
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big_endian = TRUE;
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lseek(fd, seekback, SEEK_SET);
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cli_dbgmsg("vba_readdir: Guessing big-endian\n");
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} else {
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cli_dbgmsg("vba_readdir: Guessing little-endian\n");
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}
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/* junk some more stuff */
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do
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if (cli_readn(fd, &ffff, 2) != 2) {
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close(fd);
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return NULL;
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}
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while(ffff != 0xFFFF);
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/* check for alignment error */
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if(!seekandread(fd, -3, SEEK_CUR, &ffff, sizeof(uint16_t))) {
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close(fd);
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return NULL;
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}
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if (ffff != 0xFFFF)
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lseek(fd, 1, SEEK_CUR);
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if(!read_uint16(fd, &ffff, big_endian)) {
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close(fd);
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return NULL;
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}
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if(ffff != 0xFFFF)
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lseek(fd, ffff, SEEK_CUR);
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if(!read_uint16(fd, &ffff, big_endian)) {
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close(fd);
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return NULL;
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}
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if(ffff == 0xFFFF)
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ffff = 0;
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lseek(fd, ffff + 100, SEEK_CUR);
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if(!read_uint16(fd, &record_count, big_endian)) {
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close(fd);
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return NULL;
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}
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cli_dbgmsg("vba_readdir: VBA Record count %d\n", record_count);
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if (record_count == 0) {
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/* No macros, assume clean */
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close(fd);
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return NULL;
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}
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if (record_count > MAX_VBA_COUNT) {
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/* Almost certainly an error */
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cli_dbgmsg("vba_readdir: VBA Record count too big\n");
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close(fd);
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return NULL;
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}
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vba_project = create_vba_project(record_count, dir, U);
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if(vba_project == NULL) {
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close(fd);
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return NULL;
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}
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buf = NULL;
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buflen = 0;
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for(i = 0; i < record_count; i++) {
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uint16_t length;
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char *ptr;
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vba_project->colls[i] = 0;
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if(!read_uint16(fd, &length, big_endian))
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break;
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if (length == 0) {
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cli_dbgmsg("vba_readdir: zero name length\n");
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break;
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}
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if(length > buflen) {
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unsigned char *newbuf = (unsigned char *)cli_realloc(buf, length);
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if(newbuf == NULL)
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break;
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buflen = length;
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buf = newbuf;
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}
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if (cli_readn(fd, buf, length) != length) {
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cli_dbgmsg("vba_readdir: read name failed\n");
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break;
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}
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ptr = get_unicode_name((const char *)buf, length, big_endian);
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if(ptr == NULL) break;
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if (!(vba_project->colls[i]=uniq_get(U, ptr, strlen(ptr), &hash))) {
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cli_dbgmsg("vba_readdir: cannot find project %s (%s)\n", ptr, hash);
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free(ptr);
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break;
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}
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cli_dbgmsg("vba_readdir: project name: %s (%s)\n", ptr, hash);
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free(ptr);
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vba_project->name[i] = hash;
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if(!read_uint16(fd, &length, big_endian))
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break;
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lseek(fd, length, SEEK_CUR);
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if(!read_uint16(fd, &ffff, big_endian))
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break;
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if (ffff == 0xFFFF) {
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lseek(fd, 2, SEEK_CUR);
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if(!read_uint16(fd, &ffff, big_endian))
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break;
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lseek(fd, ffff + 8, SEEK_CUR);
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} else
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lseek(fd, ffff + 10, SEEK_CUR);
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|
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if(!read_uint16(fd, &byte_count, big_endian))
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break;
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lseek(fd, (8 * byte_count) + 5, SEEK_CUR);
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if(!read_uint32(fd, &offset, big_endian))
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break;
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cli_dbgmsg("vba_readdir: offset: %u\n", (unsigned int)offset);
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vba_project->offset[i] = offset;
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lseek(fd, 2, SEEK_CUR);
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}
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if(buf)
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free(buf);
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|
|
close(fd);
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|
|
if(i < record_count) {
|
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free(vba_project->name);
|
|
free(vba_project->colls);
|
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free(vba_project->dir);
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free(vba_project->offset);
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free(vba_project);
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return NULL;
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}
|
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|
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return vba_project;
|
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}
|
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|
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unsigned char *
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cli_vba_inflate(int fd, off_t offset, int *size)
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{
|
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unsigned int pos, shift, mask, distance, clean;
|
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uint8_t flag;
|
|
uint16_t token;
|
|
blob *b;
|
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unsigned char buffer[VBA_COMPRESSION_WINDOW];
|
|
|
|
if(fd < 0)
|
|
return NULL;
|
|
|
|
b = blobCreate();
|
|
|
|
if(b == NULL)
|
|
return NULL;
|
|
|
|
lseek(fd, offset+3, SEEK_SET); /* 1byte ?? , 2byte length ?? */
|
|
clean = TRUE;
|
|
pos = 0;
|
|
|
|
while (cli_readn(fd, &flag, 1) == 1) {
|
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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)) {
|
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blobDestroy(b);
|
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if(size)
|
|
*size = 0;
|
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return NULL;
|
|
}
|
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shift = 12 - (winpos > 0x10)
|
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- (winpos > 0x20)
|
|
- (winpos > 0x40)
|
|
- (winpos > 0x80)
|
|
- (winpos > 0x100)
|
|
- (winpos > 0x200)
|
|
- (winpos > 0x400)
|
|
- (winpos > 0x800);
|
|
len = (uint16_t)((token & ((1 << shift) - 1)) + 3);
|
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distance = token >> shift;
|
|
|
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srcpos = pos - distance - 1;
|
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if((((srcpos + len) % VBA_COMPRESSION_WINDOW) < winpos) &&
|
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((winpos + len) < VBA_COMPRESSION_WINDOW) &&
|
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(((srcpos % VBA_COMPRESSION_WINDOW) + len) < VBA_COMPRESSION_WINDOW) &&
|
|
(len <= VBA_COMPRESSION_WINDOW)) {
|
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srcpos %= VBA_COMPRESSION_WINDOW;
|
|
memcpy(&buffer[winpos], &buffer[srcpos],
|
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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) {
|
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blobDestroy(b);
|
|
if(size)
|
|
*size = 0;
|
|
return NULL;
|
|
}
|
|
(void)blobAddData(b, buffer, VBA_COMPRESSION_WINDOW);
|
|
clean = FALSE;
|
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break;
|
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}
|
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if(cli_readn(fd, &buffer[winpos], 1) == 1)
|
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pos++;
|
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}
|
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clean = TRUE;
|
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}
|
|
}
|
|
|
|
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)
|
|
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;
|
|
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 {
|
|
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)
|
|
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)
|
|
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);
|
|
return NULL;
|
|
}
|
|
ret->count = record_count;
|
|
ret->U = U;
|
|
|
|
return ret;
|
|
}
|
|
|