Difference between revisions of "Unit ASN.1"
From Ultibo.org
| Line 5: | Line 5: | ||
---- | ---- | ||
| − | '''Ultibo ASN.1 | + | '''Ultibo ASN.1 Interface unit''' |
Abstract Syntax Notation One (ASN.1) is an interface description language for defining data structures that can be serialized and deserialized in a standard, cross-platform way. It's broadly used in telecommunications and computer networking, and especially in cryptography. | Abstract Syntax Notation One (ASN.1) is an interface description language for defining data structures that can be serialized and deserialized in a standard, cross-platform way. It's broadly used in telecommunications and computer networking, and especially in cryptography. | ||
Latest revision as of 04:38, 31 August 2021
Return to Unit Reference
Description
Ultibo ASN.1 Interface unit
Abstract Syntax Notation One (ASN.1) is an interface description language for defining data structures that can be serialized and deserialized in a standard, cross-platform way. It's broadly used in telecommunications and computer networking, and especially in cryptography.
This unit currently only provides the basic functionality required by X509 to read and parse a certificate in DER format.
It is expected that this unit will be expanded to incorporate additional functions over time.
Constants
ASN1 specific constants
ASN1_* ASN1_TAG_EOC = $00;
|
Not used with DER |
ASN1_TAG_BOOLEAN = $01;
|
|
ASN1_TAG_INTEGER = $02;
|
|
ASN1_TAG_BITSTRING = $03;
|
|
ASN1_TAG_OCTETSTRING = $04;
|
|
ASN1_TAG_NULL = $05;
|
|
ASN1_TAG_OID = $06;
|
|
ASN1_TAG_OBJECT_DESCRIPTOR = $07;
|
Not supported |
ASN1_TAG_EXTERNAL = $08;
|
Not supported |
ASN1_TAG_REAL = $09;
|
Not supported |
ASN1_TAG_ENUMERATED = $0A;
|
Not supported |
ASN1_TAG_EMBEDDED_PDV = $0B;
|
Not supported |
ASN1_TAG_UTF8STRING = $0C;
|
Not supported |
ANS1_TAG_RELATIVE_OID = $0D;
|
|
ASN1_TAG_SEQUENCE = $10;
|
Constructed |
ASN1_TAG_SET = $11;
|
|
ASN1_TAG_NUMERICSTRING = $12;
|
Not supported |
ASN1_TAG_PRINTABLESTRING = $13;
|
|
ASN1_TAG_TG1STRING = $14;
|
Not supported |
ASN1_TAG_VIDEOTEXSTRING = $15;
|
Not supported |
ASN1_TAG_IA5STRING = $16;
|
|
ASN1_TAG_UTCTIME = $17;
|
|
ASN1_TAG_GENERALIZEDTIME = $18;
|
Not supported |
ASN1_TAG_GRAPHICSTRING = $19;
|
Not supported |
ASN1_TAG_VISIBLESTRING = $1A;
|
|
ASN1_TAG_GENERALSTRING = $1B;
|
Not supported |
ASN1_TAG_UNIVERSALSTRING = $1C;
|
Not supported |
ASN1_TAG_CHARACTERSTRING = $1D;
|
Not supported |
ASN1_TAG_BMPSTRING = $1E;
|
Not supported |
ASN1_TAG_LONGFORM = $1F;
|
Tag is encoded in long form |
ASN1_CLASS_UNIVERSAL = 0;
|
|
ASN1_CLASS_APPLICATION = 1;
|
|
ASN1_CLASS_CONTEXT_SPECIFIC = 2;
|
|
ASN1_CLASS_PRIVATE = 3;
|
|
ASN1_MAX_OID_LEN = 20;
|
|
Type definitions
ASN1 tag
PASN1Tag = ^TASN1Tag;
TASN1Tag = record
TagNumber:LongWord;
|
|
TagClass:LongWord;
|
|
Length:LongWord;
|
|
Constructed:Boolean;
|
|
Contents:PByte;
|
ASN1 OID
PASN1OID = ^TASN1OID;
TASN1OID = record
Len:Integer;
|
|
OID:array[0..ASN1_MAX_OID_LEN - 1] of LongWord;
|
Public variables
None defined
Function declarations
ASN1 functions
function ASN1GetTag(Buffer:PByte; Len:Integer; var Tag:TASN1Tag):Boolean;
Description: To be documented
| Note | None documented |
|---|
function ASN1ParseOID(Buffer:PByte; Len:Integer; var OID:TASN1OID):Boolean;
Description: Parse an OID value from the buffer
| Note | None documented |
|---|
function ASN1GetOID(Buffer:PByte; Len:Integer; var OID:TASN1OID; var Next:PByte):Boolean;
Description: Read the next ASN1 tag from buffer and decode it as an OID value
| Note | None documented |
|---|
function ASN1GetNull(Buffer:PByte; Len:Integer; var Next:PByte):Boolean;
Description: Read the next ASN1 tag from buffer and decode it as a null value
| Note | None documented |
|---|
function ASN1ParseInt(Buffer:PByte; Len:Integer; var Value:Integer):Boolean;
Description: Parse an integer value from the buffer
| Note | None documented |
|---|
function ASN1ParseBigInt(Buffer:PByte; Len:Integer; var Value:PByte; var Size:Integer):Boolean;
Description: Parse a big integer value from the buffer (Does not include the leading negative byte if present)
| Note | Memory allocated for Value must be freed by the caller when no longer required |
|---|
function ASN1GetInt(Buffer:PByte; Len:Integer; var Value:Integer; var Next:PByte):Boolean;
Description: Read the next ASN1 tag from buffer and decode it as an integer value
| Note | None documented |
|---|
function ASN1ParseBoolean(Buffer:PByte; Len:Integer; var Value:Boolean):Boolean;
Description: Parse a boolean value from the buffer
| Note | None documented |
|---|
function ASN1GetBoolean(Buffer:PByte; Len:Integer; var Value:Boolean; var Next:PByte):Boolean;
Description: Read the next ASN1 tag from buffer and decode it as a boolean value
| Note | None documented |
|---|
ASN1 helper functions
function ASN1OIDEqual(const OID1,OID2:TASN1OID):Boolean;
Description: To be documented
| Note | None documented |
|---|
function ASN1OIDEqualPrefix(const OIDPrefix,OID:TASN1OID):Boolean;
Description: To be documented
| Note | None documented |
|---|
function ASN1OIDToString(const OID:TASN1OID):String;
Description: To be documented
| Note | None documented |
|---|
function ASN1BitStringToLongWord(Buffer:PByte; Len:Integer):LongWord;
Description: To be documented
| Note | None documented |
|---|
Return to Unit Reference
