1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
use std::io::{Read, Write};
use std::net::{Shutdown, TcpStream, ToSocketAddrs};
use std::sync::atomic::Ordering::Relaxed;
use crate::{global_variable, size};
use crate::error::SshError;
use crate::global_variable::encryption_key;
pub struct Client {
pub(crate) stream: TcpStream,
sequence: Sequence,
pub(crate) sender_window_size: u32,
}
impl Client {
pub fn clone(&self) -> Result<Client, SshError>{
let client = Client {
stream: match self.stream.try_clone() {
Ok(v) => v,
Err(e) => return Err(SshError::from(e))
},
sequence: self.sequence.clone(),
sender_window_size: self.sender_window_size
};
Ok(client)
}
}
#[derive(Clone)]
struct Sequence {
client_sequence_num: u32,
server_sequence_num: u32
}
impl Sequence {
fn client_auto_increment(&mut self) {
if self.client_sequence_num == u32::MAX {
self.client_sequence_num = 0;
}
self.client_sequence_num += 1;
}
fn server_auto_increment(&mut self) {
if self.server_sequence_num == u32::MAX {
self.server_sequence_num = 0;
}
self.server_sequence_num += 1;
}
}
impl Client {
pub fn connect<A: ToSocketAddrs>(adder: A) -> Result<Client, SshError> {
match TcpStream::connect(adder) {
Ok(stream) =>
Ok(
Client{
stream,
sequence: Sequence {
client_sequence_num: 0,
server_sequence_num: 0
},
sender_window_size: 0
}
),
Err(e) => Err(SshError::from(e))
}
}
pub fn read_version(&mut self) -> Vec<u8> {
let mut v = [0_u8; 128];
loop {
match self.stream.read(&mut v) {
Ok(i) => { return (&v[..i]).to_vec() }
Err(_) => continue
};
}
}
pub fn read(&mut self) -> Result<Vec<Vec<u8>>, SshError> {
let mut results = vec![];
let mut buf = vec![0; size::BUF_SIZE as usize];
let result = self.stream.read(&mut buf);
if result.is_err() {
return Ok(results)
}
let len = result.unwrap();
if !global_variable::IS_ENCRYPT.load(Relaxed) {
self.sequence.server_auto_increment();
results.push((&buf[..len]).to_vec());
self.sender_window_size += len as u32;
return Ok(results)
}
if len == 0 {
return Ok(results)
}
self.read_handle((&buf[..len]).to_vec(), &mut results)?;
Ok(results)
}
fn read_handle(&mut self, mut result: Vec<u8>, results: &mut Vec<Vec<u8>>) -> Result<(), SshError> {
self.sequence.server_auto_increment();
let key = encryption_key()?;
let mut packet_len_slice = [0_u8; 4];
let len = &result[..4];
packet_len_slice.copy_from_slice(len);
let packet_len_slice = key.server_key.decrypt_packet_length(self.sequence.server_sequence_num, packet_len_slice);
let packet_len = u32::from_be_bytes(packet_len_slice);
let data_len = (packet_len + 4 + 16) as usize;
loop {
if result.len() >= data_len { break }
let mut buf = vec![0; size::BUF_SIZE as usize];
let len = self.stream.read(&mut buf)?;
buf.truncate(len);
result.extend(buf)
}
let (this, remaining) = result.split_at_mut(data_len);
let decryption_result =
key.decryption(self.sequence.server_sequence_num, &mut this.to_vec())?;
self.sender_window_size += (decryption_result.len() + 16) as u32;
results.push(decryption_result);
if remaining.len() > 0 {
self.read_handle(remaining.to_vec(), results)?;
}
Ok(())
}
pub fn write_version(&mut self, buf: &[u8]) -> Result<(), SshError> {
match self.stream.write(&buf) {
Ok(_) => Ok(()),
Err(e) => Err(SshError::from(e))
}
}
pub fn write(&mut self, buf: &[u8]) -> Result<(), SshError> {
let mut buf = buf.to_vec();
if global_variable::IS_ENCRYPT.load(Relaxed) {
let key = encryption_key()?;
key.encryption(self.sequence.client_sequence_num, &mut buf);
}
self.sequence.client_auto_increment();
match self.stream.write(&buf) {
Ok(_) => {}
Err(e) => return Err(SshError::from(e))
};
match self.stream.flush() {
Ok(_) => {}
Err(e) => return Err(SshError::from(e))
};
Ok(())
}
pub(crate) fn close(self) -> Result<(), SshError> {
match self.stream.shutdown(Shutdown::Both) {
Ok(o) => Ok(o),
Err(e) => Err(SshError::from(e))
}
}
}
