This document describes the Libtasn1 library that provides
Abstract Syntax Notation One (ASN.1, as specified by the X.680 ITU-T
recommendation) parsing and structures management,
and Distinguished Encoding Rules (DER, as per X.690) encoding and
The main features of this library are:
- On-line ASN.1 structure management that doesn’t require any
C code file generation.
- Off-line ASN.1 structure management with C code file generation
containing an array.
- Distinguished Encoding Rules (DER) encoding support.
- No limits for INTEGER and ENUMERATED values.
- It’s Free Software.
Anybody can use, modify, and redistribute the library under the terms
of the GNU Lesser General Public License version 2.1 or later. The
command line tools, self-tests and build infrastructure are licensed
under the GNU General Public License version 3.0 or later.
No global variables are used and multiple library handles and session
handles may be used in parallel.
The code should work on all Unix like operating systems, and Windows.
The library itself should be portable to any C89 system, not even
POSIX is required.