---
name: "asn1_expand_octet_string"
section: "3"
platform: "linux"
package: "libtasn1"
version: "4.21.0-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/asn1_expand_octet_string"
---

# asn1\_expand\_octet\_string(3)

API function

## NAME

asn1\_expand\_octet\_string - API function

## SYNOPSIS

**#include \<libtasn1.h\>**

**int asn1\_expand\_octet\_string(asn1\_node\_const** *definitions***, asn1\_node \*** *element***, const char \*** *octetName***, const char \*** *objectName***);**

## ARGUMENTS

- asn1\_node\_const definitions

  ASN1 definitions

- asn1\_node \* element

  pointer to an ASN1 structure

- const char \* octetName

  name of the OCTET STRING field to expand.

- const char \* objectName

  name of the OBJECT IDENTIFIER field to use to define the type for expansion.

## DESCRIPTION

Expands an "OCTET STRING" element of a structure created from a DER decoding process (the **asn1\_der\_decoding()** function).  The type used for expansion is the first one following the definition of the actual value of the OBJECT IDENTIFIER indicated by OBJECTNAME.

## RETURNS

**ASN1\_SUCCESS** if substitution OK, **ASN1\_ELEMENT\_NOT\_FOUND** if  *objectName* or  *octetName* are not correct, **ASN1\_VALUE\_NOT\_VALID** if it wasn't possible to find the type to use for expansion, or other errors depending on DER decoding.

## COPYRIGHT

Copyright © 2006-2025 Free Software Foundation, Inc..\
 Copying and distribution of this file, with or without modification, are permitted in any medium without royalty provided the copyright notice and this notice are preserved.

## SEE ALSO

The full documentation for **libtasn1** is maintained as a Texinfo manual.  If the **info** and **libtasn1** programs are properly installed at your site, the command

-

  **info libtasn1**

should give you access to the complete manual. As an alternative you may obtain the manual from:

-

  **https://www.gnu.org/software/libtasn1/manual/**