Cleanup, basic readme.

README.md

@@ -0,0 +1,12 @@
+tetanus: work-in-progress repo for ZeroTier in (mostly) pure Rust
+======
+
+![Rust](artwork/rust.png)
+
+---
+
+This repository will go away or be mothballed in the future. It's a work in progress and is a bit of a monorepo that will probably get broken up eventually.
+
+The ZeroTier Rust code is currently sort of unlicensed pending actual release. We haven't decided what license to use yet, but we plan on it being something FOSS-friendlier than the current BSL in the old repo.
+
+---

aes-gmac-siv/src/impl_openssl.rs

@@ -185,11 +185,8 @@ impl AesGmacSiv {
         let mut tag_tmp = [0_u8; 32];
         let _ = Crypter::new(aes_ecb_by_key_size(self.k1.len()), Mode::Decrypt, self.k1.as_slice(), None).unwrap().update(&self.tag, &mut tag_tmp);
         self.tag.copy_from_slice(&tag_tmp[0..16]);
-        unsafe {
-            let tmp = self.tmp.as_mut_ptr().cast::<u64>();
-            *tmp = *self.tag.as_mut_ptr().cast::<u64>();
-            *tmp.offset(1) = 0;
-        }
+        self.tmp[0..8].copy_from_slice(&tag_tmp[0..8]);
+        self.tmp[8..12].fill(0);
         let _ = self.gmac.replace(Crypter::new(aes_gcm_by_key_size(self.k0.len()), Mode::Encrypt, self.k0.as_slice(), Some(&self.tmp[0..12])).unwrap());
     }
 
@@ -234,7 +231,7 @@ impl AesGmacSiv {
         unsafe {
             // tag[8..16] == tmp[0..8] ^ tmp[8..16]
             let tmp = self.tmp.as_mut_ptr().cast::<u64>();
-            if *self.tag.as_mut_ptr().cast::<u64>().offset(1) == *tmp ^ *tmp.offset(1) {
+            if *self.tag.as_mut_ptr().cast::<u64>().offset(1) == *tmp ^ *tmp.add(1) {
                 Some(&self.tag)
             } else {
                 None

zerotier-core-crypto/src/hex.rs

@@ -4,7 +4,7 @@ pub const HEX_CHARS: [u8; 16] = [b'0', b'1', b'2', b'3', b'4', b'5', b'6', b'7',
 
 /// Encode a byte slice to a hexadecimal string.
 pub fn to_string(b: &[u8]) -> String {
-    let mut s = String::new();
+    let mut s = String::with_capacity(b.len() * 2);
     s.reserve(b.len() * 2);
     for c in b {
         let x = *c as usize;
@@ -16,8 +16,7 @@ pub fn to_string(b: &[u8]) -> String {
 
 /// Encode an unsigned 64-bit value as a hexadecimal string.
 pub fn to_string_u64(mut i: u64, skip_leading_zeroes: bool) -> String {
-    let mut s = String::new();
-    s.reserve(16);
+    let mut s = String::with_capacity(16);
     for _ in 0..16 {
         let ii = i >> 60;
         if ii != 0 || !s.is_empty() || !skip_leading_zeroes {
@@ -30,8 +29,7 @@ pub fn to_string_u64(mut i: u64, skip_leading_zeroes: bool) -> String {
 
 /// Encode an unsigned 64-bit value as a hexadecimal ASCII string.
 pub fn to_vec_u64(mut i: u64, skip_leading_zeroes: bool) -> Vec<u8> {
-    let mut s = Vec::new();
-    s.reserve(16);
+    let mut s = Vec::with_capacity(16);
     for _ in 0..16 {
         let ii = i >> 60;
         if ii != 0 || !s.is_empty() || !skip_leading_zeroes {
@@ -44,9 +42,7 @@ pub fn to_vec_u64(mut i: u64, skip_leading_zeroes: bool) -> Vec<u8> {
 
 /// Decode a hex string, ignoring all non-hexadecimal characters.
 pub fn from_string(s: &str) -> Vec<u8> {
-    let mut b: Vec<u8> = Vec::new();
-    b.reserve((s.len() / 2) + 1);
-
+    let mut b: Vec<u8> = Vec::with_capacity((s.len() / 2) + 1);
     let mut byte = 0_u8;
     let mut have_8: bool = false;
     for cc in s.as_bytes() {
@@ -71,13 +67,12 @@ pub fn from_string(s: &str) -> Vec<u8> {
             have_8 = !have_8;
         }
     }
-
     b
 }
 
-/// Encode bytes from 'b' into hex characters in 'dest'.
+/// Encode bytes from 'b' into hex characters in 'dest' and return the number of hex characters written.
 /// This will panic if the destination slice is smaller than twice the length of the source.
-pub fn to_hex_bytes(b: &[u8], dest: &mut [u8]) {
+pub fn to_hex_bytes(b: &[u8], dest: &mut [u8]) -> usize {
     let mut j = 0;
     for c in b {
         let x = *c as usize;
@@ -85,4 +80,5 @@ pub fn to_hex_bytes(b: &[u8], dest: &mut [u8]) {
         dest[j + 1] = HEX_CHARS[x & 0xf];
         j += 2;
     }
+    j
 }

zerotier-core-crypto/src/p384.rs

@@ -177,6 +177,8 @@ impl P384KeyPair {
     }
 
     /// Perform ECDH key agreement, returning the raw (un-hashed!) ECDH secret.
+    ///
+    /// This secret should not be used directly. It should be hashed and perhaps used in a KDF.
     pub fn agree(&self, other_public: &P384PublicKey) -> Option<Secret<P384_ECDH_SHARED_SECRET_SIZE>> {
         unsafe {
             let mut s: Secret<P384_ECDH_SHARED_SECRET_SIZE> = Secret::default();

zerotier-core-crypto/src/poly1305.rs

@@ -11,12 +11,9 @@ pub const POLY1305_MAC_SIZE: usize = 16;
 
 impl Poly1305 {
     #[inline(always)]
-    pub fn new(key: &[u8]) -> Option<Poly1305> {
-        if key.len() == 32 {
-            Some(Self(poly1305::Poly1305::new(poly1305::Key::from_slice(key))))
-        } else {
-            None
-        }
+    pub fn new(key: &[u8]) -> Poly1305 {
+        assert_eq!(key.len(), 32);
+        Self(poly1305::Poly1305::new(poly1305::Key::from_slice(key)))
     }
 
     #[inline(always)]

zerotier-network-hypervisor/src/vl1/peer.rs

@@ -75,7 +75,8 @@ fn salsa_poly_create(secret: &SymmetricSecret, header: &PacketHeader, packet_siz
     let mut salsa = Salsa::<12>::new(&key.0, &header.id);
     let mut poly1305_key = [0_u8; 32];
     salsa.crypt_in_place(&mut poly1305_key);
-    (salsa, Poly1305::new(&poly1305_key).unwrap())
+
+    (salsa, Poly1305::new(&poly1305_key))
 }
 
 /// Attempt AEAD packet encryption and MAC validation. Returns message ID on success.