Skip to content

Commit a25daf8

Browse files
calvinmetcalfcalvinmetcalf
committed
96 bit nonces
1 parent 4587877 commit a25daf8

File tree

1 file changed

+155
-8
lines changed

1 file changed

+155
-8
lines changed

‎src/chacha20.rs

Lines changed: 155 additions & 8 deletions
Original file line numberDiff line numberDiff line change
@@ -84,7 +84,7 @@ static S7:u32x4 = u32x4(7, 7, 7, 7);
8484
impl ChaCha20 {
8585
pub fn new(key: &[u8], nonce: &[u8]) -> ChaCha20 {
8686
assert!(key.len() == 16 || key.len() == 32);
87-
assert!(nonce.len() == 8);
87+
assert!(nonce.len() == 8 || nonce.len() == 12);
8888

8989
ChaCha20{ state: ChaCha20::expand(key, nonce), output: [0u8; 64], offset: 64 }
9090
}
@@ -124,12 +124,21 @@ impl ChaCha20 {
124124
read_u32_le(&key[28..32])
125125
)
126126
},
127-
d: u32x4(
128-
0,
129-
0,
130-
read_u32_le(&nonce[0..4]),
131-
read_u32_le(&nonce[4..8])
132-
)
127+
d: if nonce.len() == 12 {
128+
u32x4(
129+
0,
130+
read_u32_le(&nonce[0..4]),
131+
read_u32_le(&nonce[4..8]),
132+
read_u32_le(&nonce[8..12])
133+
)
134+
} else {
135+
u32x4(
136+
0,
137+
0,
138+
read_u32_le(&nonce[0..4]),
139+
read_u32_le(&nonce[4..8])
140+
)
141+
}
133142
}
134143
}
135144

@@ -153,7 +162,10 @@ impl ChaCha20 {
153162
self.state.d += u32x4(1, 0, 0, 0);
154163
let u32x4(c12, _, _, _) = self.state.d;
155164
if c12 == 0 {
156-
self.state.d += u32x4(0, 1, 0, 0);
165+
// we could increment the other counter word with an 8 byte nonce
166+
// but other implementations like boringssl have this same
167+
// limitation
168+
panic!("counter is exhausted");
157169
}
158170

159171
self.offset = 0;
@@ -334,6 +346,141 @@ mod test {
334346
assert_eq!(output, tv.keystream);
335347
}
336348
}
349+
350+
#[test]
351+
fn test_chacha20_256_tls_vectors_96_nonce() {
352+
struct TestVector {
353+
key: [u8; 32],
354+
nonce: [u8; 12],
355+
keystream: Vec<u8>,
356+
};
357+
// taken from http://tools.ietf.org/html/draft-agl-tls-chacha20poly1305-04
358+
let test_vectors = vec!(
359+
TestVector{
360+
key: [
361+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
362+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
363+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
364+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
365+
],
366+
nonce: [ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 ],
367+
keystream: vec!(
368+
0x76, 0xb8, 0xe0, 0xad, 0xa0, 0xf1, 0x3d, 0x90,
369+
0x40, 0x5d, 0x6a, 0xe5, 0x53, 0x86, 0xbd, 0x28,
370+
0xbd, 0xd2, 0x19, 0xb8, 0xa0, 0x8d, 0xed, 0x1a,
371+
0xa8, 0x36, 0xef, 0xcc, 0x8b, 0x77, 0x0d, 0xc7,
372+
0xda, 0x41, 0x59, 0x7c, 0x51, 0x57, 0x48, 0x8d,
373+
0x77, 0x24, 0xe0, 0x3f, 0xb8, 0xd8, 0x4a, 0x37,
374+
0x6a, 0x43, 0xb8, 0xf4, 0x15, 0x18, 0xa1, 0x1c,
375+
0xc3, 0x87, 0xb6, 0x69, 0xb2, 0xee, 0x65, 0x86,
376+
),
377+
}, TestVector{
378+
key: [
379+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
380+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
381+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
382+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01,
383+
],
384+
nonce: [ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 ],
385+
keystream: vec!(
386+
0x45, 0x40, 0xf0, 0x5a, 0x9f, 0x1f, 0xb2, 0x96,
387+
0xd7, 0x73, 0x6e, 0x7b, 0x20, 0x8e, 0x3c, 0x96,
388+
0xeb, 0x4f, 0xe1, 0x83, 0x46, 0x88, 0xd2, 0x60,
389+
0x4f, 0x45, 0x09, 0x52, 0xed, 0x43, 0x2d, 0x41,
390+
0xbb, 0xe2, 0xa0, 0xb6, 0xea, 0x75, 0x66, 0xd2,
391+
0xa5, 0xd1, 0xe7, 0xe2, 0x0d, 0x42, 0xaf, 0x2c,
392+
0x53, 0xd7, 0x92, 0xb1, 0xc4, 0x3f, 0xea, 0x81,
393+
0x7e, 0x9a, 0xd2, 0x75, 0xae, 0x54, 0x69, 0x63,
394+
),
395+
}, TestVector{
396+
key: [
397+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
398+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
399+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
400+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
401+
],
402+
nonce: [ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01 ],
403+
keystream: vec!(
404+
0xde, 0x9c, 0xba, 0x7b, 0xf3, 0xd6, 0x9e, 0xf5,
405+
0xe7, 0x86, 0xdc, 0x63, 0x97, 0x3f, 0x65, 0x3a,
406+
0x0b, 0x49, 0xe0, 0x15, 0xad, 0xbf, 0xf7, 0x13,
407+
0x4f, 0xcb, 0x7d, 0xf1, 0x37, 0x82, 0x10, 0x31,
408+
0xe8, 0x5a, 0x05, 0x02, 0x78, 0xa7, 0x08, 0x45,
409+
0x27, 0x21, 0x4f, 0x73, 0xef, 0xc7, 0xfa, 0x5b,
410+
0x52, 0x77, 0x06, 0x2e, 0xb7, 0xa0, 0x43, 0x3e,
411+
0x44, 0x5f, 0x41, 0xe3,
412+
),
413+
}, TestVector{
414+
key: [
415+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
416+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
417+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
418+
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
419+
],
420+
nonce: [ 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 ],
421+
keystream: vec!(
422+
0xef, 0x3f, 0xdf, 0xd6, 0xc6, 0x15, 0x78, 0xfb,
423+
0xf5, 0xcf, 0x35, 0xbd, 0x3d, 0xd3, 0x3b, 0x80,
424+
0x09, 0x63, 0x16, 0x34, 0xd2, 0x1e, 0x42, 0xac,
425+
0x33, 0x96, 0x0b, 0xd1, 0x38, 0xe5, 0x0d, 0x32,
426+
0x11, 0x1e, 0x4c, 0xaf, 0x23, 0x7e, 0xe5, 0x3c,
427+
0xa8, 0xad, 0x64, 0x26, 0x19, 0x4a, 0x88, 0x54,
428+
0x5d, 0xdc, 0x49, 0x7a, 0x0b, 0x46, 0x6e, 0x7d,
429+
0x6b, 0xbd, 0xb0, 0x04, 0x1b, 0x2f, 0x58, 0x6b,
430+
),
431+
}, TestVector{
432+
key: [
433+
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
434+
0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
435+
0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
436+
0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
437+
],
438+
nonce: [0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07 ],
439+
keystream: vec!(
440+
0xf7, 0x98, 0xa1, 0x89, 0xf1, 0x95, 0xe6, 0x69,
441+
0x82, 0x10, 0x5f, 0xfb, 0x64, 0x0b, 0xb7, 0x75,
442+
0x7f, 0x57, 0x9d, 0xa3, 0x16, 0x02, 0xfc, 0x93,
443+
0xec, 0x01, 0xac, 0x56, 0xf8, 0x5a, 0xc3, 0xc1,
444+
0x34, 0xa4, 0x54, 0x7b, 0x73, 0x3b, 0x46, 0x41,
445+
0x30, 0x42, 0xc9, 0x44, 0x00, 0x49, 0x17, 0x69,
446+
0x05, 0xd3, 0xbe, 0x59, 0xea, 0x1c, 0x53, 0xf1,
447+
0x59, 0x16, 0x15, 0x5c, 0x2b, 0xe8, 0x24, 0x1a,
448+
0x38, 0x00, 0x8b, 0x9a, 0x26, 0xbc, 0x35, 0x94,
449+
0x1e, 0x24, 0x44, 0x17, 0x7c, 0x8a, 0xde, 0x66,
450+
0x89, 0xde, 0x95, 0x26, 0x49, 0x86, 0xd9, 0x58,
451+
0x89, 0xfb, 0x60, 0xe8, 0x46, 0x29, 0xc9, 0xbd,
452+
0x9a, 0x5a, 0xcb, 0x1c, 0xc1, 0x18, 0xbe, 0x56,
453+
0x3e, 0xb9, 0xb3, 0xa4, 0xa4, 0x72, 0xf8, 0x2e,
454+
0x09, 0xa7, 0xe7, 0x78, 0x49, 0x2b, 0x56, 0x2e,
455+
0xf7, 0x13, 0x0e, 0x88, 0xdf, 0xe0, 0x31, 0xc7,
456+
0x9d, 0xb9, 0xd4, 0xf7, 0xc7, 0xa8, 0x99, 0x15,
457+
0x1b, 0x9a, 0x47, 0x50, 0x32, 0xb6, 0x3f, 0xc3,
458+
0x85, 0x24, 0x5f, 0xe0, 0x54, 0xe3, 0xdd, 0x5a,
459+
0x97, 0xa5, 0xf5, 0x76, 0xfe, 0x06, 0x40, 0x25,
460+
0xd3, 0xce, 0x04, 0x2c, 0x56, 0x6a, 0xb2, 0xc5,
461+
0x07, 0xb1, 0x38, 0xdb, 0x85, 0x3e, 0x3d, 0x69,
462+
0x59, 0x66, 0x09, 0x96, 0x54, 0x6c, 0xc9, 0xc4,
463+
0xa6, 0xea, 0xfd, 0xc7, 0x77, 0xc0, 0x40, 0xd7,
464+
0x0e, 0xaf, 0x46, 0xf7, 0x6d, 0xad, 0x39, 0x79,
465+
0xe5, 0xc5, 0x36, 0x0c, 0x33, 0x17, 0x16, 0x6a,
466+
0x1c, 0x89, 0x4c, 0x94, 0xa3, 0x71, 0x87, 0x6a,
467+
0x94, 0xdf, 0x76, 0x28, 0xfe, 0x4e, 0xaa, 0xf2,
468+
0xcc, 0xb2, 0x7d, 0x5a, 0xaa, 0xe0, 0xad, 0x7a,
469+
0xd0, 0xf9, 0xd4, 0xb6, 0xad, 0x3b, 0x54, 0x09,
470+
0x87, 0x46, 0xd4, 0x52, 0x4d, 0x38, 0x40, 0x7a,
471+
0x6d, 0xeb, 0x3a, 0xb7, 0x8f, 0xab, 0x78, 0xc9,
472+
),
473+
},
474+
);
475+
476+
for tv in test_vectors.iter() {
477+
let mut c = ChaCha20::new(&tv.key, &tv.nonce);
478+
let input: Vec<u8> = repeat(0).take(tv.keystream.len()).collect();
479+
let mut output: Vec<u8> = repeat(0).take(input.len()).collect();
480+
c.process(&input[], &mut output[]);
481+
assert_eq!(output, tv.keystream);
482+
}
483+
}
337484
}
338485

339486
#[cfg(test)]

0 commit comments

Comments
 (0)