Example #1
0
static struct zip_cdir *
_zip_read_eocd(const unsigned char *eocd, const unsigned char *buf, off_t buf_offset, size_t buflen,
	       unsigned int flags, struct zip_error *error)
{
    struct zip_cdir *cd;
    const unsigned char *cdp;
    zip_uint64_t i, nentry, size, offset;

    if (eocd+EOCDLEN > buf+buflen) {
	_zip_error_set(error, ZIP_ER_INCONS, 0);
	return NULL;
    }

    cdp = eocd + 8;

    /* number of cdir-entries on this disk */
    i = _zip_read2(&cdp);
    /* number of cdir-entries */
    nentry = _zip_read2(&cdp);

    if (nentry != i) {
	_zip_error_set(error, ZIP_ER_NOZIP, 0);
	return NULL;
    }

    size = _zip_read4(&cdp);
    offset = _zip_read4(&cdp);

    if (size > ZIP_OFF_MAX || offset > ZIP_OFF_MAX || offset+size > ZIP_OFF_MAX) {
        _zip_error_set(error, ZIP_ER_SEEK, EFBIG);
        return NULL;
    }

    if (offset+size > (zip_uint64_t)(buf_offset + (eocd-buf))) {
	/* cdir spans past EOCD record */
	_zip_error_set(error, ZIP_ER_INCONS, 0);
	return NULL;
    }

    if ((flags & ZIP_CHECKCONS) && offset+size != (zip_uint64_t)(buf_offset + (eocd-buf))) {
	_zip_error_set(error, ZIP_ER_INCONS, 0);
	return NULL;
    }

    if ((cd=_zip_cdir_new(nentry, error)) == NULL)
	return NULL;

    cd->size = (off_t)size;
    cd->offset = (off_t)offset;

    return cd;
}
Example #2
0
static struct zip_cdir *
_zip_readcdir(FILE *fp, unsigned char *buf, unsigned char *eocd, int buflen,
	      int flags, struct zip_error *error)
{
    struct zip_cdir *cd;
    unsigned char *cdp, **bufp;
    int i, comlen, nentry;
    unsigned int left;

    comlen = buf + buflen - eocd - EOCDLEN;
    if (comlen < 0) {
	/* not enough bytes left for comment */
	_zip_error_set(error, ZIP_ER_NOZIP, 0);
	return NULL;
    }

    /* check for end-of-central-dir magic */
    if (memcmp(eocd, EOCD_MAGIC, 4) != 0) {
	_zip_error_set(error, ZIP_ER_NOZIP, 0);
	return NULL;
    }

    if (memcmp(eocd+4, "\0\0\0\0", 4) != 0) {
	_zip_error_set(error, ZIP_ER_MULTIDISK, 0);
	return NULL;
    }

    cdp = eocd + 8;
    /* number of cdir-entries on this disk */
    i = _zip_read2(&cdp);
    /* number of cdir-entries */
    nentry = _zip_read2(&cdp);

    if ((cd=_zip_cdir_new(nentry, error)) == NULL)
	return NULL;

    cd->size = _zip_read4(&cdp);
    cd->offset = _zip_read4(&cdp);
    cd->comment = NULL;
    cd->comment_len = _zip_read2(&cdp);

    if ((comlen < cd->comment_len) || (cd->nentry != i)) {
	_zip_error_set(error, ZIP_ER_NOZIP, 0);
	free(cd);
	return NULL;
    }
    if ((flags & ZIP_CHECKCONS) && comlen != cd->comment_len) {
	_zip_error_set(error, ZIP_ER_INCONS, 0);
	free(cd);
	return NULL;
    }

    if (cd->comment_len) {
	if ((cd->comment=(char *)_zip_memdup(eocd+EOCDLEN,
					     cd->comment_len, error))
	    == NULL) {
	    free(cd);
	    return NULL;
	}
    }

    if (cd->size < (unsigned int)(eocd-buf)) {
	/* if buffer already read in, use it */
	cdp = eocd - cd->size;
	bufp = &cdp;
    }
    else {
	/* go to start of cdir and read it entry by entry */
	bufp = NULL;
	clearerr(fp);
	fseeko(fp, cd->offset, SEEK_SET);
	/* possible consistency check: cd->offset =
	   len-(cd->size+cd->comment_len+EOCDLEN) ? */
	if (ferror(fp) || ((unsigned long)ftello(fp) != cd->offset)) {
	    /* seek error or offset of cdir wrong */
	    if (ferror(fp))
		_zip_error_set(error, ZIP_ER_SEEK, errno);
	    else
		_zip_error_set(error, ZIP_ER_NOZIP, 0);
	    free(cd);
	    return NULL;
	}
    }

    left = cd->size;
    i=0;
    do {
	if (i == cd->nentry && left > 0) {
	    /* Infozip extension for more than 64k entries:
	       nentries wraps around, size indicates correct EOCD */
	    _zip_cdir_grow(cd, cd->nentry+0x10000, error);
	}

	if ((_zip_dirent_read(cd->entry+i, fp, bufp, &left, 0, error)) < 0) {
	    cd->nentry = i;
	    _zip_cdir_free(cd);
	    return NULL;
	}
	i++;
	
    } while (i<cd->nentry);
    
    return cd;
}
Example #3
0
static struct zip_cdir *
_zip_readcdir(FILE *fp, off_t buf_offset, unsigned char *buf, unsigned char *eocd, int buflen,
	      int flags, struct zip_error *error)
{
    struct zip_cdir *cd;
    unsigned char *cdp, **bufp;
    int i, comlen, nentry;
    zip_uint32_t left;

    comlen = buf + buflen - eocd - EOCDLEN;
    if (comlen < 0) {
	/* not enough bytes left for comment */
	_zip_error_set(error, ZIP_ER_NOZIP, 0);
	return NULL;
    }

    /* check for end-of-central-dir magic */
    if (memcmp(eocd, EOCD_MAGIC, 4) != 0) {
	_zip_error_set(error, ZIP_ER_NOZIP, 0);
	return NULL;
    }

    if (memcmp(eocd+4, "\0\0\0\0", 4) != 0) {
	_zip_error_set(error, ZIP_ER_MULTIDISK, 0);
	return NULL;
    }

    cdp = eocd + 8;
    /* number of cdir-entries on this disk */
    i = _zip_read2(&cdp);
    /* number of cdir-entries */
    nentry = _zip_read2(&cdp);

    if ((cd=_zip_cdir_new(nentry, error)) == NULL)
	return NULL;

    cd->size = _zip_read4(&cdp);
    cd->offset = _zip_read4(&cdp);
    cd->comment = NULL;
    cd->comment_len = _zip_read2(&cdp);

	/* without checking the ZIP_CHECKCONS flag we'll not able even to open inconsistent
	   archives at this place, which would break bc in PHP */
    if ((ZIP_CHECKCONS == (flags & ZIP_CHECKCONS)) && ((zip_uint64_t)cd->offset)+cd->size > buf_offset + (eocd-buf)) {
	/* cdir spans past EOCD record */
	_zip_error_set(error, ZIP_ER_INCONS, 0);
	cd->nentry = 0;
	_zip_cdir_free(cd);
	return NULL;
    }

    if ((comlen < cd->comment_len) || (cd->nentry != i)) {
	_zip_error_set(error, ZIP_ER_NOZIP, 0);
	cd->nentry = 0;
	_zip_cdir_free(cd);
	return NULL;
    }
    if ((flags & ZIP_CHECKCONS) && comlen != cd->comment_len) {
	_zip_error_set(error, ZIP_ER_INCONS, 0);
	cd->nentry = 0;
	_zip_cdir_free(cd);
	return NULL;
    }

    if (cd->comment_len) {
	if ((cd->comment=(char *)_zip_memdup(eocd+EOCDLEN,
					     cd->comment_len, error))
	    == NULL) {
	    cd->nentry = 0;
	    _zip_cdir_free(cd);
	    return NULL;
	}
    }

	/* the first if branch goes the old way of libzip 0.9 so we don't loose 
	   the bc for reading inconsistent files */
	if ((ZIP_CHECKCONS != (flags & ZIP_CHECKCONS)) && cd->size < (unsigned int)(eocd-buf)) {
	cdp = eocd - cd->size;
	bufp = &cdp;
	}
	else if (cd->offset >= buf_offset) {
	/* if buffer already read in, use it */
	cdp = buf + (cd->offset - buf_offset);
	bufp = &cdp;
    }
    else {
	/* go to start of cdir and read it entry by entry */
	bufp = NULL;
	clearerr(fp);
	fseeko(fp, cd->offset, SEEK_SET);
	/* possible consistency check: cd->offset =
	   len-(cd->size+cd->comment_len+EOCDLEN) ? */
	if (ferror(fp) || ((unsigned long)ftello(fp) != cd->offset)) {
	    /* seek error or offset of cdir wrong */
	    if (ferror(fp))
		_zip_error_set(error, ZIP_ER_SEEK, errno);
	    else
		_zip_error_set(error, ZIP_ER_NOZIP, 0);
	    cd->nentry = 0;
	    _zip_cdir_free(cd);
	    return NULL;
	}
    }

    left = cd->size;
    i=0;
    while (i<cd->nentry && left > 0) {
	if ((_zip_dirent_read(cd->entry+i, fp, bufp, &left, 0, error)) < 0) {
	    cd->nentry = i;
	    _zip_cdir_free(cd);
	    return NULL;
	}
	i++;
	
	if (i == cd->nentry && left > 0) {
	    /* Infozip extension for more than 64k entries:
	       nentries wraps around, size indicates correct EOCD */
	    if (_zip_cdir_grow(cd, cd->nentry+ZIP_UINT16_MAX, error) < 0) {
		cd->nentry = i;
		_zip_cdir_free(cd);
		return NULL;
	    }
	}
    }

    cd->nentry = i;
    
    return cd;
}