This document describes the changes made to old versions of the
asn1
application.Asn1 1.0.3
Fixed errors and malfunctions
- The
asn1.app
file is corrected.
Own Id: OTP-2640- The encoding of integers in BER did not comply with the standard for all values. The values was not encoded in the minimum number of octets as required. This is now corrected in the runtime module
asn1rt_ber
.
Own Id: OTP-2666Improvements and new features
- The compiler now generates explicit exports directives for all generated functions that should be exported (instead of -compile(export_all)). This eliminates the warnings from the Erlang compiler when compiling the generated file.
Own Id: OTP-1845R3B02 (Asn1 1.0.2)
Fixed errors and malfunctions
- The decoding of a BER encoded SEQUENCE with optional component of type SEQUENCE (also with optional components) could result in an error or wrong result if the tags are equal.
Own Id: OTP-2226- The encoding of (PER) SEQUENCE with extensionmark was wrong. This is now corrected.
Own Id: OTP-2349R3A (Asn1 0.9)
Fixed errors and malfunctions
- The asn1 compiler now detects the use of an implicit tag before
CHOICE
as an error (in accordance with the standard)
Own Id: OTP-1844- An OPTIONAL CHOICE embedded in SEQUENCE when BER coding caused an error when generating decode code. This is now corrected.
Own Id: OTP-1857
Aux Id: OTP-18481 ASN1 0.8.1
This is the first release of the ASN1 application. This version is released for beta-testing. Some functionality will be added until the 1.0 version is released. See the release notes for the latest version for the exact details about new features. A list of missing features and restrictions can be found in the chapter below.
1.1 Missing features and other restrictions
- The encoding rules BER and PER (aligned) is supported. PER (unaligned) IS NOT SUPPORTED.
- NOT SUPPORTED types
ANY
andANY DEFINED BY
(is not in the standard any more).
- NOT SUPPORTED types
EXTERNAL
andEMBEDDED-PDV
.
- NOT SUPPORTED type
REAL
(planned to be implemented).
- The code generation support for value definitions in the ASN.1 notation is very limited (planned to be enhanced).
- The support for constraints is limited to:
Complex expressions in constraints is not supported (planned to be extended).
- SizeConstraint SIZE(X)
- SingleValue (1)
- ValueRange (X..Y)
- PermittedAlpabet FROM (but not for BMPString and UniversalString when generating PER).
- The current version of the compiler has very limited error checking:
- Stops at first syntax error.
- Does not stop when a reference to an undefined type is found , but prints an error message. Compilation of the generated Erlang module will then fail.
- A whole number of other semantical controls is currently missing. This means that the compiler will give little or bad help to detect what's wrong with an ASN.1 specification, but will mostly work very well when the ASN.1 specification is correct.
- The maximum INTEGER supported in this version is a signed 64 bit integer. This limitation is probably quite reasonable. (Planned to be extended).
- Only AUTOMATIC TAGS supported for PER.
- Only EXPLICIT and IMPLICIT TAGS supported for BER.
- The compiler supports decoding of BER-data with indefinite length but it is not possible to produce data with indefinite length with the encoder.