1 files changed, 101 insertions, 0 deletions
diff --git a/module/asn1.m b/module/asn1.m
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+++ b/module/asn1.m
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+ASN1: module {
+	PATH: con "/dis/lib/asn1.dis";
+
+	# Tag classes
+	Universal : con 0;
+	Application : con 16r40;
+	Context : con 16r80;
+	Private : con 16rC0;
+
+	# Universal tags
+	BOOLEAN : con 1;
+	INTEGER : con 2;
+	BIT_STRING : con 3;
+	OCTET_STRING : con 4;
+	NULL : con 5;
+	OBJECT_ID: con 6;
+	ObjectDescriptor : con 7;
+	EXTERNAL : con 8;
+	REAL : con 9;
+	ENUMERATED : con 10;
+	EMBEDDED_PDV : con 11;
+	SEQUENCE : con 16;		# also SEQUENCE OF
+	SET : con 17;			# also SET  OF
+	NumericString : con 18;
+	PrintableString : con 19;
+	TeletexString : con 20;
+	VideotexString : con 21;
+	IA5String : con 22;
+	UTCTime : con 23;
+	GeneralizedTime : con 24;
+	GraphicString : con 25;
+	VisibleString : con 26;
+	GeneralString : con 27;
+	UniversalString : con 28;
+	BMPString : con 30;
+
+	Elem: adt {
+		tag: Tag;
+		val: ref Value;
+
+		is_seq: fn(e: self ref Elem) : (int, list of ref Elem);
+		is_set: fn(e: self ref Elem) : (int, list of ref Elem);
+		is_int: fn(e: self ref Elem) : (int, int);
+		is_bigint: fn(e: self ref Elem) : (int, array of byte);
+		is_bitstring: fn(e: self ref Elem) : (int, int, array of byte);
+		is_octetstring: fn(e: self ref Elem) : (int, array of byte);
+		is_oid: fn(e: self ref Elem) : (int, ref Oid);
+		is_string: fn(e: self ref Elem) : (int, string);
+		is_time: fn(e: self ref Elem) : (int, string);
+		tostring: fn(e: self ref Elem) : string;
+	};
+
+	Tag: adt {
+		class: int;
+		num: int;
+		constr: int;	# ignored by encode()
+
+		tostring: fn(t: self Tag) : string;
+	};
+
+	Value: adt {
+		pick {
+			Bool or Int =>
+				v: int;
+			Octets or BigInt or Real or Other =>
+				# BigInt: integer too big for limbo int
+				# Real: we don't care to decode these
+				#    since they are hardly ever used
+				bytes: array of byte;
+			BitString =>
+				# pack into bytes, with perhaps some
+				# unused bits in last byte
+				unusedbits: int;
+				bits: array of byte;
+			Null or EOC =>
+				dummy: int;
+			ObjId =>
+				id: ref Oid;
+			String =>
+				s: string;
+			Seq or Set =>
+				l: list of ref Elem;
+		}
+
+		tostring : fn(v: self ref Value) : string;
+	};
+
+	Oid: adt {
+		nums: array of int;
+
+		tostring: fn(o: self ref Oid) : string;
+	};
+
+	init: fn();
+	decode: fn(a: array of byte) : (string, ref Elem);
+	decode_seq: fn(a: array of byte) : (string, list of ref Elem);
+	decode_value: fn(a: array of byte, kind, constr: int) : (string, ref Value);
+	encode: fn(e: ref Elem) : (string, array of byte);
+	oid_lookup: fn(o: ref Oid, tab: array of Oid) : int;
+	print_elem: fn(e: ref Elem);
+};