Repo of no-std crates for my personal embedded projects
Improve mix_nonce
+18
-19
+18
-19
sachy-crypto/src/lib.rs
+18
-19
sachy-crypto/src/lib.rs
···
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msg: &mut alloc::vec::Vec<u8>,
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associated_data: &[u8],
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) -> Result<(), ProtoError> {
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+
if self.counter.ct_eq(&TransportState::COUNTER_MAX).into() {
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+
return Err(ProtoError);
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+
}
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+
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let counter = self.counter.to_be_bytes();
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self.transport.aead.encrypt_in_place(
···
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self.counter = self.counter.wrapping_add(TransportState::COUNTER_INCR);
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-
if self.counter.ct_eq(&TransportState::COUNTER_MAX).into() {
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-
Err(ProtoError)
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-
} else {
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-
Ok(())
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-
}
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+
Ok(())
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}
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}
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···
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msg: &mut alloc::vec::Vec<u8>,
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associated_data: &[u8],
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) -> Result<(), ProtoError> {
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+
if self.counter.ct_eq(&TransportState::COUNTER_MAX).into() {
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+
return Err(ProtoError);
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+
}
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+
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let counter = self.counter.to_be_bytes();
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self.transport.aead.decrypt_in_place(
···
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self.counter = self.counter.wrapping_add(TransportState::COUNTER_INCR);
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-
if self.counter.ct_eq(&TransportState::COUNTER_MAX).into() {
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-
Err(ProtoError)
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-
} else {
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-
Ok(())
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-
}
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+
Ok(())
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}
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}
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···
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let epstein = self.select_nonce_context(send);
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-
let (head, tail) = trump.split_at_mut(position.len());
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-
let (first, second) = epstein.split_at(position.len());
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+
let trump_len = trump.len();
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-
// XOR the base nonce with position bytes, copying them to the derived nonce
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-
head.iter_mut()
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-
.zip(first)
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.zip(position)
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-
.for_each(|((head, ep), pos)| *head = ep ^ pos);
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+
// Copy position bytes into BE format onto derived nonce
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+
trump[trump_len - position.len()..].copy_from_slice(position);
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279
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-
// Copy rest of base nonce into derived nonce
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-
tail.copy_from_slice(second);
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+
// XOR the base nonce onto the derived nonce bytes
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+
trump
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+
.iter_mut()
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+
.zip(epstein)
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+
.for_each(|(trump, epstein)| *trump ^= epstein);
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trump
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}