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
|
extern crate matasano;
extern crate rand;
use rand::Rng;
mod util;
#[test]
fn problem_25 () {
let key = util::random_aes_128_key();
let nonce: u64 = rand::thread_rng().gen();
let plaintext = util::read("data/25.txt");
let ciphertext = matasano::aes_128_ctr(&plaintext[..], &key[..], nonce);
let edit = |ciphertext: &[u8], offset: usize, newtext: &[u8]| {
let block_start_number = offset / 16;
let block_start = block_start_number * 16;
let block_end_number = (offset + newtext.len() - 1) / 16;
let block_end = std::cmp::min(
(block_end_number + 1) * 16,
ciphertext.len()
);
let mut plaintext = matasano::aes_128_ctr_with_counter(
&ciphertext[block_start..block_end],
&key[..],
nonce,
(offset / 16) as u64
);
for i in 0..newtext.len() {
plaintext[offset - block_start + i] = newtext[i];
}
let new_ciphertext = matasano::aes_128_ctr_with_counter(
&plaintext[..],
&key[..],
nonce,
(offset / 16) as u64
);
return ciphertext
.iter()
.take(block_start)
.chain(new_ciphertext.iter())
.chain(ciphertext.iter().skip(block_end))
.map(|x| *x)
.collect();
};
let got = matasano::crack_aes_128_ctr_random_access(&ciphertext[..], edit);
assert_eq!(&got[..], &plaintext[..]);
}
#[test]
fn problem_26 () {
let key = util::random_aes_128_key();
let nonce = rand::thread_rng().gen();
let prefix = "comment1=cooking%20MCs;userdata=";
let suffix = ";comment2=%20like%20a%20pound%20of%20bacon";
let admin = ";admin=true;";
let escape = |input: &str| {
input.replace("%", "%25").replace(";", "%3B").replace("=", "%3D")
};
let encode = |input: &str| -> Vec<u8> {
let plaintext: Vec<u8> = prefix
.as_bytes()
.iter()
.chain(escape(input).as_bytes().iter())
.chain(suffix.as_bytes().iter())
.map(|x| *x)
.collect();
return matasano::aes_128_ctr(&plaintext[..], &key[..], nonce);
};
let verify = |ciphertext: &[u8]| -> bool {
let plaintext = matasano::aes_128_ctr(ciphertext, &key[..], nonce);
return (0..(plaintext.len() - admin.len())).any(|i| {
plaintext
.iter()
.skip(i)
.zip(admin.as_bytes().iter())
.all(|(&c1, &c2)| c1 == c2)
});
};
let ciphertext = matasano::crack_ctr_bitflipping(&encode);
assert!(verify(&ciphertext[..]));
}
#[test]
fn problem_27 () {
let key = util::random_aes_128_key();
let iv = key;
let prefix = "comment1=cooking%20MCs;userdata=";
let suffix = ";comment2=%20like%20a%20pound%20of%20bacon";
let admin = ";admin=true;";
let escape = |input: &str| {
input.replace("%", "%25").replace(";", "%3B").replace("=", "%3D")
};
let encode = |input: &str| -> Vec<u8> {
let plaintext: Vec<u8> = prefix
.as_bytes()
.iter()
.chain(escape(input).as_bytes().iter())
.chain(suffix.as_bytes().iter())
.map(|x| *x)
.collect();
return matasano::encrypt_aes_128_cbc(&plaintext[..], &key[..], &iv[..]);
};
let verify = |ciphertext: &[u8]| -> Result<bool, Vec<u8>> {
let plaintext = matasano::decrypt_aes_128_cbc(ciphertext, &key[..], &iv[..]).unwrap();
if plaintext.iter().any(|&c| c < 32 || c > 126) {
return Err(plaintext);
}
else {
return Ok(
(0..(plaintext.len() - admin.len())).any(|i| {
plaintext
.iter()
.skip(i)
.zip(admin.as_bytes().iter())
.all(|(&c1, &c2)| c1 == c2)
})
);
}
};
let ciphertext = matasano::crack_cbc_iv_key(&encode, &verify);
assert!(verify(&ciphertext[..]).unwrap());
}
// problem 28 is just matasano::sha1_mac
|
