if (length == 0) length=(unsigned int)num;
if (offset >= num) { BIO_printf(bio_err, "Error: offset too large\n"); goto end; }  num -= offset;  if ((length == 0) || (length > num)) length=(unsigned int)num;
int MAIN(int argc, char **argv)	{	int i,badops=0,offset=0,ret=1,j;	unsigned int length=0;	long num,tmplen;	BIO *in=NULL,*out=NULL,*b64=NULL, *derout = NULL;	int informat,indent=0, noout = 0, dump = 0;	char *infile=NULL,*str=NULL,*prog,*oidfile=NULL, *derfile=NULL;	char *genstr=NULL, *genconf=NULL;	unsigned char *tmpbuf;	BUF_MEM *buf=NULL;	STACK *osk=NULL;	ASN1_TYPE *at=NULL;	informat=FORMAT_PEM;	apps_startup();	if (bio_err == NULL)		if ((bio_err=BIO_new(BIO_s_file())) != NULL)			BIO_set_fp(bio_err,stderr,BIO_NOCLOSE|BIO_FP_TEXT);	if (!load_config(bio_err, NULL))		goto end;	prog=argv[0];	argc--;	argv++;	if ((osk=sk_new_null()) == NULL)		{		BIO_printf(bio_err,"Memory allocation failure\n");		goto end;		}	while (argc >= 1)		{		if 	(strcmp(*argv,"-inform") == 0)			{			if (--argc < 1) goto bad;			informat=str2fmt(*(++argv));			}		else if (strcmp(*argv,"-in") == 0)			{			if (--argc < 1) goto bad;			infile= *(++argv);			}		else if (strcmp(*argv,"-out") == 0)			{			if (--argc < 1) goto bad;			derfile= *(++argv);			}		else if (strcmp(*argv,"-i") == 0)			{			indent=1;			}		else if (strcmp(*argv,"-noout") == 0) noout = 1;		else if (strcmp(*argv,"-oid") == 0)			{			if (--argc < 1) goto bad;			oidfile= *(++argv);			}		else if (strcmp(*argv,"-offset") == 0)			{			if (--argc < 1) goto bad;			offset= atoi(*(++argv));			}		else if (strcmp(*argv,"-length") == 0)			{			if (--argc < 1) goto bad;			length= atoi(*(++argv));			if (length == 0) goto bad;			}		else if (strcmp(*argv,"-dump") == 0)			{			dump= -1;			}		else if (strcmp(*argv,"-dlimit") == 0)			{			if (--argc < 1) goto bad;			dump= atoi(*(++argv));			if (dump <= 0) goto bad;			}		else if (strcmp(*argv,"-strparse") == 0)			{			if (--argc < 1) goto bad;			sk_push(osk,*(++argv));			}		else if (strcmp(*argv,"-genstr") == 0)			{			if (--argc < 1) goto bad;			genstr= *(++argv);			}		else if (strcmp(*argv,"-genconf") == 0)			{			if (--argc < 1) goto bad;			genconf= *(++argv);			}		else			{			BIO_printf(bio_err,"unknown option %s\n",*argv);			badops=1;			break;			}		argc--;		argv++;		}	if (badops)		{bad:		BIO_printf(bio_err,"%s [options] <infile\n",prog);		BIO_printf(bio_err,"where options are\n");		BIO_printf(bio_err," -inform arg   input format - one of DER TXT PEM\n");		BIO_printf(bio_err," -in arg       input file\n");		BIO_printf(bio_err," -out arg      output file (output format is always DER\n");		BIO_printf(bio_err," -noout arg    don't produce any output\n");		BIO_printf(bio_err," -offset arg   offset into file\n");		BIO_printf(bio_err," -length arg   length of section in file\n");		BIO_printf(bio_err," -i            indent entries\n");		BIO_printf(bio_err," -dump         dump unknown data in hex form\n");		BIO_printf(bio_err," -dlimit arg   dump the first arg bytes of unknown data in hex form\n");		BIO_printf(bio_err," -oid file     file of extra oid definitions\n");		BIO_printf(bio_err," -strparse offset\n");		BIO_printf(bio_err,"               a series of these can be used to 'dig' into multiple\n");		BIO_printf(bio_err,"               ASN1 blob wrappings\n");		BIO_printf(bio_err," -genstr str   string to generate ASN1 structure from\n");		BIO_printf(bio_err," -genconf file file to generate ASN1 structure from\n");		goto end;		}	ERR_load_crypto_strings();	in=BIO_new(BIO_s_file());	out=BIO_new(BIO_s_file());	if ((in == NULL) || (out == NULL))		{		ERR_print_errors(bio_err);		goto end;		}	BIO_set_fp(out,stdout,BIO_NOCLOSE|BIO_FP_TEXT);#ifdef OPENSSL_SYS_VMS	{	BIO *tmpbio = BIO_new(BIO_f_linebuffer());	out = BIO_push(tmpbio, out);	}#endif	if (oidfile != NULL)		{		if (BIO_read_filename(in,oidfile) <= 0)			{			BIO_printf(bio_err,"problems opening %s\n",oidfile);			ERR_print_errors(bio_err);			goto end;			}		OBJ_create_objects(in);		}	if (infile == NULL)		BIO_set_fp(in,stdin,BIO_NOCLOSE);	else		{		if (BIO_read_filename(in,infile) <= 0)			{			perror(infile);			goto end;			}		}	if (derfile) {		if(!(derout = BIO_new_file(derfile, "wb"))) {			BIO_printf(bio_err,"problems opening %s\n",derfile);			ERR_print_errors(bio_err);			goto end;		}	}	if ((buf=BUF_MEM_new()) == NULL) goto end;	if (!BUF_MEM_grow(buf,BUFSIZ*8)) goto end; /* Pre-allocate :-) */	if (genstr || genconf)		{		num = do_generate(bio_err, genstr, genconf, buf);		if (num < 0)			{			ERR_print_errors(bio_err);			goto end;			}		}	else		{		if (informat == FORMAT_PEM)			{			BIO *tmp;			if ((b64=BIO_new(BIO_f_base64())) == NULL)				goto end;			BIO_push(b64,in);			tmp=in;			in=b64;			b64=tmp;			}		num=0;		for (;;)			{			if (!BUF_MEM_grow(buf,(int)num+BUFSIZ)) goto end;			i=BIO_read(in,&(buf->data[num]),BUFSIZ);			if (i <= 0) break;			num+=i;			}		}	str=buf->data;	/* If any structs to parse go through in sequence */	if (sk_num(osk))		{		tmpbuf=(unsigned char *)str;		tmplen=num;		for (i=0; i<sk_num(osk); i++)			{			ASN1_TYPE *atmp;			j=atoi(sk_value(osk,i));			if (j == 0)				{				BIO_printf(bio_err,"'%s' is an invalid number\n",sk_value(osk,i));				continue;				}			tmpbuf+=j;			tmplen-=j;			atmp = at;			at = d2i_ASN1_TYPE(NULL,&tmpbuf,tmplen);			ASN1_TYPE_free(atmp);			if(!at)				{				BIO_printf(bio_err,"Error parsing structure\n");				ERR_print_errors(bio_err);				goto end;				}			/* hmm... this is a little evil but it works */			tmpbuf=at->value.asn1_string->data;			tmplen=at->value.asn1_string->length;			}		str=(char *)tmpbuf;		num=tmplen;		}	if (length == 0) length=(unsigned int)num;	if(derout) {		if(BIO_write(derout, str + offset, length) != (int)length) {			BIO_printf(bio_err, "Error writing output\n");			ERR_print_errors(bio_err);			goto end;		}	}	if (!noout &&	    !ASN1_parse_dump(out,(unsigned char *)&(str[offset]),length,		    indent,dump))		{		ERR_print_errors(bio_err);		goto end;		}	ret=0;end:	BIO_free(derout);	if (in != NULL) BIO_free(in);	if (out != NULL) BIO_free_all(out);	if (b64 != NULL) BIO_free(b64);	if (ret != 0)		ERR_print_errors(bio_err);	if (buf != NULL) BUF_MEM_free(buf);	if (at != NULL) ASN1_TYPE_free(at);	if (osk != NULL) sk_free(osk);	OBJ_cleanup();	apps_shutdown();	OPENSSL_EXIT(ret);	}