toe_beans/v4/message/
decode.rs

1use crate::v4::error::Result;
2
3/// Define how the bytes of a DHCP message's fields
4/// decode into your custom Message's types.
5///
6/// ...or don't and use our homemade [Message](crate::v4::message::Message)
7/// with this already implemented.
8pub trait DecodeMessage {
9    /// The type your custom Message uses to represent the op field.
10    type Op;
11    /// The type your custom Message uses to represent the htype field.
12    type Htype;
13    /// The type your custom Message uses to represent the hlen field.
14    type Hlen;
15    /// The type your custom Message uses to represent the hops field.
16    type Hops;
17    /// The type your custom Message uses to represent the xid field.
18    type Xid;
19    /// The type your custom Message uses to represent the secs field.
20    type Secs;
21    /// The type your custom Message uses to represent the flags field.
22    type Flags;
23    /// The type your custom Message uses to represent the ciaddr field.
24    type Ciaddr;
25    /// The type your custom Message uses to represent the yiaddr field.
26    type Yiaddr;
27    /// The type your custom Message uses to represent the siaddr field.
28    type Siaddr;
29    /// The type your custom Message uses to represent the giaddr field.
30    type Giaddr;
31    /// The type your custom Message uses to represent the chaddr field.
32    type Chaddr;
33    /// The type your custom Message uses to represent the sname field.
34    type Sname;
35    /// The type your custom Message uses to represent the file field.
36    type File;
37    /// The type your custom Message uses to represent the magic field.
38    type Magic;
39    /// The type your custom Message uses to represent the options field.
40    type Options;
41
42    /// Your custom Message.
43    type Output;
44
45    /// Convert an op field's byte into your custom Message's type.
46    fn decode_op(op: &[u8]) -> Self::Op;
47    /// Convert an htype field's byte into your custom Message's type.
48    fn decode_htype(htype: &[u8]) -> Self::Htype;
49    /// Convert an hlen field's byte into your custom Message's type.
50    fn decode_hlen(hlen: &[u8]) -> Self::Hlen;
51    /// Convert an hops field's byte into your custom Message's type.
52    fn decode_hops(hops: &[u8]) -> Self::Hops;
53    /// Convert an xid field's bytes into your custom Message's type.
54    fn decode_xid(xid: &[u8]) -> Self::Xid;
55    /// Convert an secs field's bytes into your custom Message's type.
56    fn decode_secs(secs: &[u8]) -> Self::Secs;
57    /// Convert an flags field's bytes into your custom Message's type.
58    fn decode_flags(flags: &[u8]) -> Self::Flags;
59    /// Convert an ciaddr field's bytes into your custom Message's type.
60    fn decode_ciaddr(ciaddr: &[u8]) -> Self::Ciaddr;
61    /// Convert an yiaddr field's bytes into your custom Message's type.
62    fn decode_yiaddr(yiaddr: &[u8]) -> Self::Yiaddr;
63    /// Convert an siaddr field's bytes into your custom Message's type.
64    fn decode_siaddr(siaddr: &[u8]) -> Self::Siaddr;
65    /// Convert an giaddr field's bytes into your custom Message's type.
66    fn decode_giaddr(giaddr: &[u8]) -> Self::Giaddr;
67    /// Convert an chaddr field's bytes into your custom Message's type.
68    fn decode_chaddr(chaddr: &[u8]) -> Self::Chaddr;
69    /// Convert an sname field's bytes into your custom Message's type.
70    fn decode_sname(sname: &[u8]) -> Self::Sname;
71    /// Convert an file field's bytes into your custom Message's type.
72    fn decode_file(file: &[u8]) -> Self::File;
73    /// Convert an magic field's bytes into your custom Message's type.
74    fn decode_magic(magic: &[u8]) -> Self::Magic;
75    /// Convert an options field's bytes into your custom Message's type.
76    fn decode_options(options: &[u8]) -> Self::Options;
77
78    /// decodes a byte array slice into a [Message](crate::v4::Message) or other type that implements decodeMessage.
79    fn from_bytes(input: &[u8]) -> Result<Self::Output>;
80}
81
82// ------------------------------------------------
83
84#[cfg(test)]
85mod tests {
86    use std::net::Ipv4Addr;
87
88    use super::*;
89    use crate::v4::*;
90
91    // Output additional debug info with
92    // RUST_LOG=debug cargo test test_from_bytes -- --show-output
93    fn init_logger() {
94        let _ = env_logger::builder().is_test(true).try_init();
95    }
96
97    #[test]
98    fn test_from_bytes() {
99        init_logger();
100
101        let bytes = &[
102            1, 1, 6, 1, 0, 0, 0, 4, 0, 2, 128, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
103            3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48,
104            48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48,
105            48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48,
106            48, 48, 48, 48, 48, 48, 48, 48, 48, 0, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
107            64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
108            64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
109            64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
110            64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
111            64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
112            64, 64, 64, 64, 64, 0, 99, 130, 83, 99, 0, 53, 1, 1, 255,
113        ];
114        let test: Message = Message::from_bytes(bytes).unwrap();
115        let expected = Message {
116            op: Ops::Request,
117            htype: HTypes::Ethernet,
118            hlen: 6,
119            hops: 1,
120            xid: 4,
121            secs: 2,
122            flags: Flags { broadcast: true },
123            ciaddr: Ipv4Addr::new(1, 1, 1, 1),
124            yiaddr: Ipv4Addr::new(1, 1, 1, 1),
125            siaddr: Ipv4Addr::new(1, 1, 1, 1),
126            giaddr: Ipv4Addr::new(1, 1, 1, 1),
127            chaddr: [3; 16],
128            sname: SName::new(c"000000000000000000000000000000000000000000000000000000000000000")
129                .unwrap(),
130            file: File::new(c"@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@").unwrap(),
131            magic: [99, 130, 83, 99],
132            options: vec![
133                MessageOptions::MessageType(MessageTypes::Discover),
134            ],
135        };
136
137        assert_eq!(expected, test);
138    }
139}
toe_beans/v4/message/decode.rs

toe_beans/v4/message/
decode.rs
