datex_core/parser/
header.rs

1use crate::{utils::{buffers::{read_u8, read_u16, read_slice, read_u32, read_u64}}, global::dxb_block::{DXBHeader, RoutingInfo, HeaderFlags, DXBBlockType}, datex_values::Endpoint};
2
3
4// checks magic number
5pub fn has_dxb_magic_number(dxb:&[u8]) -> bool {
6	dxb.len() >= 2 && dxb[0] == 0x01 && dxb[1] == 0x64
7}
8
9pub fn parse_dxb_header<'a>(dxb:&'a [u8]) -> (DXBHeader, &'a [u8]) {
10	// has magic number?
11	if !has_dxb_magic_number(dxb) {
12		panic!("Invalid DXB header format - missing magic number");
13	}
14	// header to short
15	if dxb.len() < 28 {
16		panic!("Invalid DXB header format - too short");
17	}
18
19	let index = &mut 2;
20
21	// pre header
22	let version = read_u8(dxb, index);
23	let size = read_u16(dxb, index);
24	let ttl = read_u8(dxb, index);
25	let priority = read_u8(dxb, index);
26	let signed_encrypted = read_u8(dxb, index);
27	let signed = signed_encrypted == 1 || signed_encrypted == 2; // is signed?
28	let encrypted = signed_encrypted == 2 || signed_encrypted == 3; // is encrypted?
29	let sender = get_dxb_header_sender(dxb, index);
30	let _receivers = get_dxb_header_receivers(dxb, index);
31
32	// block header
33	let scope_id = read_u32(dxb, index);
34	let block_index = read_u16(dxb, index);
35	let block_increment = read_u16(dxb, index);
36	let block_type = DXBBlockType::try_from(read_u8(dxb, index)).expect("Invalid DXB block type");
37	let _flags = read_u8(dxb, index); // TODO: parse
38	let timestamp = read_u64(dxb, index);
39
40
41	let header = DXBHeader {
42		version,
43		size,
44		signed,
45		encrypted,
46
47		scope_id,
48		block_index,
49		block_increment,
50		block_type,
51		timestamp,
52
53		flags: HeaderFlags {allow_execute:true,end_of_scope:true,device_type:0},
54		routing: RoutingInfo {ttl, sender, priority}
55	};
56
57	return (header, dxb.clone());
58}
59
60
61fn get_dxb_header_sender(dxb:&[u8], index: &mut usize) -> Option<Endpoint> {
62
63	if read_u8(dxb, index) == std::u8::MAX {
64		return None;
65	}
66	else {
67		*index -= 1;
68		return Some(Endpoint::new_from_binary(&read_slice(dxb, index, 21)))
69	}
70}
71
72
73fn get_dxb_header_receivers(dxb:&[u8], index: &mut usize) -> Option<Endpoint> {
74	if read_u16(dxb, index) == std::u16::MAX {
75		return None;
76	}
77	else {
78		// TODO:
79		return None;
80	}
81}
datex_core/parser/header.rs

datex_core/parser/
header.rs
