@widesky/node-bacstack
Version:
The BACnet protocol library written in pure JavaScript.
38 lines (34 loc) • 1.16 kB
JavaScript
const baAsn1 = require('../asn1');
const baEnum = require('../enum');
module.exports.encode = (buffer, state, password) => {
baAsn1.encodeContextEnumerated(buffer, 0, state);
if (password && password !== '') {
baAsn1.encodeContextCharacterString(buffer, 1, password);
}
};
module.exports.decode = (buffer, offset, apduLen) => {
let len = 0;
let value = {};
let result;
if (!baAsn1.decodeIsContextTag(buffer, offset + len, 0)) {
return undefined;
}
result = baAsn1.decodeTagNumberAndValue(buffer, offset + len);
len += result.len;
let decodedValue = baAsn1.decodeEnumerated(buffer, offset + len, result.value);
value.state = decodedValue.value;
len += decodedValue.len;
if (len < apduLen) {
if (!baAsn1.decodeIsContextTag(buffer, offset + len, 1)) {
return undefined;
}
result = baAsn1.decodeTagNumberAndValue(buffer, offset + len);
len += result.len;
decodedValue = baAsn1.decodeCharacterString(buffer, offset + len, apduLen - (offset + len), result.value);
value.password = decodedValue.value;
len += decodedValue.len;
}
value.len = len;
return value;
};
;