/*
* Extract VBA source code for component MS Office Documents
*
* Copyright (C) 2013-2019 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
* 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] < 0 ? 0 : 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, (size_t)length) != (size_t)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;
uint32_t hashcnt = 0;
cli_dbgmsg("in cli_vba_readdir()\n");
if (dir == NULL)
return NULL;
/*
* _VBA_PROJECT files are embedded within office documents (OLE2)
*/
if (CL_SUCCESS != uniq_get(U, "_vba_project", 12, &hash, &hashcnt)) {
cli_dbgmsg("vba_readdir: uniq_get('_vba_project') failed. Unable to check # of embedded vba proj files\n");
return NULL;
}
if (hashcnt == 0) {
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, (size_t)length) != (size_t)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 (CL_SUCCESS != uniq_get(U, ptr, strlen(ptr), &hash, &hashcnt)) {
cli_dbgmsg("vba_readdir: uniq_get('%s') failed.\n", ptr);
free(ptr);
break;
}
vba_project->colls[i] = hashcnt;
if (0 == vba_project->colls[i]) {
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, size_t *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 = 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) {
size_t todo = MIN(sizeof(data), len);
if (cli_readn(s, data, todo) != todo)
break;
if (cli_writen(d, data, todo) != todo)
break;
if (todo > len) {
break;
} else {
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, fullname, 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, (size_t)stream.avail_in) != (size_t)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, (size_t)stream.avail_in) != (size_t)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) != (size_t)(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)
{
size_t msize;
uint16_t 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 %u 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 {
size_t nread = cli_readn(fd, smallbuf, sizeof(smallbuf));
if ((nread == 0) || (nread == (size_t)-1))
return FALSE;
end = memchr(smallbuf, '\0', nread);
if (end) {
if (lseek(fd, 1 + (end - smallbuf) - (off_t)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, len) == 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_calloc(1, 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->colls == NULL) || (ret->name == NULL) || (ret->dir == NULL) || (ret->offset == NULL)) {
cli_free_vba_project(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;
}
/**
* @brief Free up the memory associated with the vba_project_t type.
*
* @param project A vba_project_t type allocated by one of these:
* - create_vba_project()
* - cli_wm_readdir()
* - cli_vba_readdir()
*/
void cli_free_vba_project(vba_project_t *vba_project)
{
if (vba_project) {
if (vba_project->dir)
free(vba_project->dir);
if (vba_project->colls)
free(vba_project->colls);
if (vba_project->name)
free(vba_project->name);
if (vba_project->offset)
free(vba_project->offset);
if (vba_project->length)
free(vba_project->length);
if (vba_project->key)
free(vba_project->key);
free(vba_project);
}
return;
}