Merge pull request 'v-0.2.0-alpha-1' (#1) from v-0.2.0-alpha-1 into main

Reviewed-on: #1

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "aes-gcm-stream"
-version = "0.1.1"
+version = "0.2.0"
 edition = "2021"
 authors = ["Hatter Jiang"]
 repository = "https://git.hatter.ink/hatter/aes-gcm-stream"
@@ -13,9 +13,11 @@ categories = ["cryptography"]
 
 [dependencies]
 aes = { version = "0.8.3", features = ["zeroize"] }
+cipher = "0.4.4"
+ghash = "0.5.0"
 zeroize = { version = "1.6.0", features = ["zeroize_derive"] }
 
 [dev-dependencies]
 hex = "0.4.3"
-aes-gcm = { version = "0.10.2", features = ["zeroize"] }
 benchmark-simple = "0.1.8"
+aes-gcm = { version = "0.10.2", features = ["zeroize"] }

examples/bench.rs

@@ -2,7 +2,7 @@ use aes_gcm::{Aes256Gcm, KeyInit};
 use aes_gcm::aead::{Aead, Nonce};
 use benchmark_simple::{Bench, Options};
 
-use aes_gcm_stream::{Aes128GcmStreamEncryptor, Aes192GcmStreamEncryptor, Aes256GcmStreamEncryptor};
+use aes_gcm_stream::{Aes128GcmStreamEncryptor, Aes192GcmStreamEncryptor, Aes256GcmStreamDecryptor, Aes256GcmStreamEncryptor};
 
 fn test_aes128_encrypt(m: &mut [u8]) {
     let key = [0u8; 16];
@@ -31,6 +31,23 @@ fn test_aes256_encrypt(m: &mut [u8]) {
     encryptor.finalize();
 }
 
+fn test_aes256_encrypted_and_decrypt(m: &mut [u8]) {
+    let key = [0u8; 32];
+    let nonce = [0u8; 12];
+    let mut encryptor = Aes256GcmStreamEncryptor::new(key.clone(), &nonce);
+
+    let mut encrypted = encryptor.update(m);
+    let (last_block, tag) = encryptor.finalize();
+    encrypted.extend_from_slice(&last_block);
+    encrypted.extend_from_slice(&tag);
+
+    let mut decryptor = Aes256GcmStreamDecryptor::new(key, &nonce);
+    let mut decrypted = decryptor.update(&encrypted);
+    let last_block = decryptor.finalize().expect("decrypt failed");
+    decrypted.extend_from_slice(&last_block);
+    assert_eq!(m, decrypted.as_slice());
+}
+
 fn test_aes256_encrypt_aesgcm(m: &mut [u8]) {
     let key = [0u8; 32];
     let nonce = [0u8; 12];
@@ -64,6 +81,9 @@ fn main() {
     let res = bench.run(options, || test_aes256_encrypt(&mut m));
     println!("AES256 encrypt         : {}", res.throughput(m.len() as _));
 
+    let res = bench.run(options, || test_aes256_encrypted_and_decrypt(&mut m));
+    println!("AES256 en/decrypt      : {}", res.throughput(m.len() as _));
+
     let res = bench.run(options, || test_aes256_encrypt_aesgcm(&mut m));
     println!("AES256 encrypt aes-gcm : {}", res.throughput(m.len() as _));
 }

src/decryptor.rs

@@ -1,9 +1,11 @@
 use aes::{Aes128, Aes192, Aes256};
 use aes::cipher::{Block, BlockEncrypt, KeyInit};
 use aes::cipher::generic_array::GenericArray;
-use zeroize::ZeroizeOnDrop;
+use ghash::GHash;
+use ghash::universal_hash::UniversalHash;
+use zeroize::Zeroize;
 
-use crate::util::{gmul_128, inc_32, msb_s, normalize_nonce, u8to128};
+use crate::util::{AesBlock, BLOCK_SIZE, inc_32, msb_s, normalize_nonce, u8to128};
 
 macro_rules! define_aes_gcm_stream_decryptor_impl {
     (
@@ -11,14 +13,10 @@ macro_rules! define_aes_gcm_stream_decryptor_impl {
         $aesn:tt,
         $key_size:tt
     ) => {
-
-#[derive(ZeroizeOnDrop)]
 pub struct $module {
-    crypto: $aesn,
+    cipher: $aesn,
     message_buffer: Vec<u8>,
-    integrality_buffer: Vec<u8>,
-    ghash_key: u128,
-    ghash_val: u128,
+    ghash: GHash,
     init_nonce: u128,
     encryption_nonce: u128,
     adata_len: usize,
@@ -30,31 +28,31 @@ impl $module {
         let key = GenericArray::from(key);
         let aes = $aesn::new(&key);
 
+        let mut ghash_key = ghash::Key::default();
+        aes.encrypt_block(&mut ghash_key);
+        let ghash = GHash::new(&ghash_key);
+        ghash_key.zeroize();
+
         let mut s = Self {
-            crypto: aes,
+            cipher: aes,
             message_buffer: vec![],
-            integrality_buffer: vec![],
-            ghash_key: 0,
-            ghash_val: 0,
+            ghash,
             init_nonce: 0,
             encryption_nonce: 0,
             adata_len: 0,
             message_len: 0,
         };
-        let (ghash_key, normalized_nonce) = s.normalize_nonce(nonce);
-        s.ghash_key = ghash_key;
+        let (_, normalized_nonce) = s.normalize_nonce(nonce);
         s.init_nonce = normalized_nonce;
         s.encryption_nonce = normalized_nonce;
         s
     }
 
     pub fn init_adata(&mut self, adata: &[u8]) {
-        self.integrality_buffer.extend_from_slice(adata);
-        self.adata_len += adata.len();
-
-        let adata_bit_len = self.adata_len * 8;
-        let v = 128 * ((adata_bit_len + 128 - 1) / 128) - adata_bit_len;
-        self.integrality_buffer.extend_from_slice(&vec![0x00; v / 8]);
+        if adata.len() > 0 {
+            self.adata_len += adata.len();
+            self.ghash.update_padded(adata);
+        }
     }
 
     pub fn update(&mut self, bytes: &[u8]) -> Vec<u8> {
@@ -65,21 +63,27 @@ impl $module {
             return Vec::with_capacity(0);
         }
         let blocks_count = (message_buffer_len / 16) - 1;
-        let mut plaintext_message = Vec::with_capacity(blocks_count * 16);
-        for i in 0..blocks_count {
-            self.encryption_nonce = inc_32(self.encryption_nonce);
-            let mut ctr = self.encryption_nonce.to_be_bytes();
-            let block = Block::<$aesn>::from_mut_slice(&mut ctr);
-            self.crypto.encrypt_block(block);
-            let chunk = &message_buffer_slice[i * 16..(i + 1) * 16];
-            let y = u8to128(chunk) ^ u8to128(&block.as_slice());
-            plaintext_message.extend_from_slice(&y.to_be_bytes());
-        }
-        self.integrality_buffer.extend_from_slice(&message_buffer_slice[0..blocks_count * 16]);
-        self.message_buffer = message_buffer_slice[blocks_count * 16..].to_vec();
-        self.message_len += plaintext_message.len();
 
-        self.update_integrality_buffer();
+        let mut blocks = Vec::with_capacity(blocks_count);
+        for _ in 0..blocks_count {
+            self.encryption_nonce = inc_32(self.encryption_nonce);
+            let ctr = self.encryption_nonce.to_be_bytes();
+            blocks.push(Block::<AesBlock>::clone_from_slice(&ctr));
+        }
+        self.cipher.encrypt_blocks(&mut blocks);
+
+        let encrypted_message = &message_buffer_slice[0..blocks_count * BLOCK_SIZE];
+        self.ghash.update_padded(encrypted_message);
+        let mut plaintext_message = encrypted_message.to_vec();
+        for i in 0..blocks_count {
+            let chunk = &mut plaintext_message[i * BLOCK_SIZE..(i + 1) * BLOCK_SIZE];
+            let block = blocks[i].as_slice();
+            for k in 0..BLOCK_SIZE {
+                chunk[k] ^= block[k];
+            }
+        }
+        self.message_buffer = message_buffer_slice[blocks_count * BLOCK_SIZE..].to_vec();
+        self.message_len += plaintext_message.len();
 
         plaintext_message
     }
@@ -91,25 +95,22 @@ impl $module {
             // last block and this block len is less than 128 bits
             self.encryption_nonce = inc_32(self.encryption_nonce);
             let mut ctr = self.encryption_nonce.to_be_bytes();
-            let block = Block::<$aesn>::from_mut_slice(&mut ctr);
-            self.crypto.encrypt_block(block);
+            let block = Block::<AesBlock>::from_mut_slice(&mut ctr);
+            self.cipher.encrypt_block(block);
 
             let chunk = &self.message_buffer[0..message_buffer_len - 16];
             let msb = msb_s(chunk.len() * 8, block.as_slice());
             let y = u8to128(chunk) ^ u8to128(&msb);
             plaintext_message.extend_from_slice(&y.to_be_bytes()[16 - chunk.len()..16]);
-            self.integrality_buffer.extend_from_slice(&self.message_buffer[0..message_buffer_len - 16]);
+            self.ghash.update_padded(&self.message_buffer[0..message_buffer_len - 16]);
             self.message_len += plaintext_message.len();
         }
         let adata_bit_len = self.adata_len * 8;
         let message_bit_len = self.message_len * 8;
-        let u = 128 * ((message_bit_len + 128 - 1) / 128) - message_bit_len;
-        self.integrality_buffer.extend_from_slice(&vec![0x00; u / 8]);
-        self.integrality_buffer.extend_from_slice(&(adata_bit_len as u64).to_be_bytes());
-        self.integrality_buffer.extend_from_slice(&(message_bit_len as u64).to_be_bytes());
-
-        self.update_integrality_buffer();
-        assert!(self.integrality_buffer.is_empty());
+        let mut adata_and_message_len = Vec::with_capacity(BLOCK_SIZE);
+        adata_and_message_len.extend_from_slice(&(adata_bit_len as u64).to_be_bytes());
+        adata_and_message_len.extend_from_slice(&(message_bit_len as u64).to_be_bytes());
+        self.ghash.update_padded(&adata_and_message_len);
 
         let tag = self.calculate_tag();
         let message_tag = &self.message_buffer[message_buffer_len - 16..];
@@ -124,30 +125,18 @@ impl $module {
 
     fn calculate_tag(&mut self) -> Vec<u8> {
         let mut bs = self.init_nonce.to_be_bytes().clone();
-        let block = Block::<$aesn>::from_mut_slice(&mut bs);
-        self.crypto.encrypt_block(block);
-        let tag_trunk = self.ghash_val.to_be_bytes();
+        let block = Block::<AesBlock>::from_mut_slice(&mut bs);
+        self.cipher.encrypt_block(block);
+        let ghash = self.ghash.clone().finalize();
+        let tag_trunk = ghash.as_slice();
         let y = u8to128(&tag_trunk) ^ u8to128(&block.as_slice());
         y.to_be_bytes().to_vec()
     }
 
-    fn update_integrality_buffer(&mut self) {
-        let integrality_buffer_slice = self.integrality_buffer.as_slice();
-        let integrality_buffer_slice_len = integrality_buffer_slice.len();
-        if integrality_buffer_slice_len >= 16 {
-            let blocks_count = integrality_buffer_slice_len / 16;
-            for i in 0..blocks_count {
-                let buf = &integrality_buffer_slice[i * 16..(i + 1) * 16];
-                self.ghash_val = gmul_128(self.ghash_val ^ u8to128(buf), self.ghash_key)
-            }
-            self.integrality_buffer = integrality_buffer_slice[blocks_count * 16..].to_vec();
-        }
-    }
-
     fn ghash_key(&mut self) -> u128 {
-        let mut block = [0u8; 16];
-        let block = Block::<$aesn>::from_mut_slice(&mut block);
-        self.crypto.encrypt_block(block);
+        let mut block = [0u8; BLOCK_SIZE];
+        let block = Block::<AesBlock>::from_mut_slice(&mut block);
+        self.cipher.encrypt_block(block);
         u8to128(&block.as_slice())
     }
 

src/encryptor.rs

@@ -1,9 +1,11 @@
 use aes::{Aes128, Aes192, Aes256};
 use aes::cipher::{Block, BlockEncrypt, KeyInit};
 use aes::cipher::generic_array::GenericArray;
-use zeroize::ZeroizeOnDrop;
+use ghash::GHash;
+use ghash::universal_hash::UniversalHash;
+use zeroize::Zeroize;
 
-use crate::util::{gmul_128, inc_32, msb_s, normalize_nonce, u8to128};
+use crate::util::{AesBlock, BLOCK_SIZE, inc_32, msb_s, normalize_nonce, u8to128};
 
 macro_rules! define_aes_gcm_stream_encryptor_impl {
     (
@@ -11,14 +13,10 @@ macro_rules! define_aes_gcm_stream_encryptor_impl {
         $aesn:tt,
         $key_size:tt
     ) => {
-
-#[derive(ZeroizeOnDrop)]
 pub struct $module {
-    crypto: $aesn,
+    cipher: $aesn,
     message_buffer: Vec<u8>,
-    integrality_buffer: Vec<u8>,
-    ghash_key: u128,
-    ghash_val: u128,
+    ghash: GHash,
     init_nonce: u128,
     encryption_nonce: u128,
     adata_len: usize,
@@ -30,117 +28,106 @@ impl $module {
         let key = GenericArray::from(key);
         let aes = $aesn::new(&key);
 
+        let mut ghash_key = ghash::Key::default();
+        aes.encrypt_block(&mut ghash_key);
+        let ghash = GHash::new(&ghash_key);
+        ghash_key.zeroize();
+
         let mut s = Self {
-            crypto: aes,
+            cipher: aes,
             message_buffer: vec![],
-            integrality_buffer: vec![],
-            ghash_key: 0,
-            ghash_val: 0,
+            ghash,
             init_nonce: 0,
             encryption_nonce: 0,
             adata_len: 0,
             message_len: 0,
         };
-        let (ghash_key, normalized_nonce) = s.normalize_nonce(nonce);
-        s.ghash_key = ghash_key;
+        let (_, normalized_nonce) = s.normalize_nonce(nonce);
         s.init_nonce = normalized_nonce;
         s.encryption_nonce = normalized_nonce;
         s
     }
 
     pub fn init_adata(&mut self, adata: &[u8]) {
-        self.integrality_buffer.extend_from_slice(adata);
-        self.adata_len += adata.len();
-
-        let adata_bit_len = self.adata_len * 8;
-        let v = 128 * ((adata_bit_len + 128 - 1) / 128) - adata_bit_len;
-        self.integrality_buffer.extend_from_slice(&vec![0x00; v / 8]);
+        if adata.len() > 0 {
+            self.adata_len += adata.len();
+            self.ghash.update_padded(adata);
+        }
     }
 
-    pub fn update(&mut self, bytes: &[u8]) -> Vec<u8> {
-        self.message_buffer.extend_from_slice(bytes);
+    pub fn update(&mut self, message: &[u8]) -> Vec<u8> {
+        self.message_buffer.extend_from_slice(message);
         let message_buffer_slice = self.message_buffer.as_slice();
-        let message_buffer_len = message_buffer_slice.len();
-        if message_buffer_len < 16 {
+        if message_buffer_slice.len() < BLOCK_SIZE {
             return Vec::with_capacity(0);
         }
-        let blocks_count = message_buffer_len / 16;
-        let mut encrypted_message = Vec::with_capacity(blocks_count * 16);
-        for i in 0..blocks_count {
+        let blocks_count = message_buffer_slice.len() / BLOCK_SIZE;
+        let mut blocks = Vec::with_capacity(blocks_count);
+        for _ in 0..blocks_count {
             self.encryption_nonce = inc_32(self.encryption_nonce);
-            let mut ctr = self.encryption_nonce.to_be_bytes();
-            let block = Block::<$aesn>::from_mut_slice(&mut ctr);
-            self.crypto.encrypt_block(block);
-            let chunk = &message_buffer_slice[i * 16..(i + 1) * 16];
-            let y = u8to128(chunk) ^ u8to128(&block.as_slice());
-            encrypted_message.extend_from_slice(&y.to_be_bytes());
+            let ctr = self.encryption_nonce.to_be_bytes();
+            blocks.push(Block::<AesBlock>::clone_from_slice(&ctr));
         }
-        self.message_buffer = message_buffer_slice[blocks_count * 16..].to_vec();
-        self.integrality_buffer.extend_from_slice(&encrypted_message);
-        self.message_len += encrypted_message.len();
+        self.cipher.encrypt_blocks(&mut blocks);
 
-        self.update_integrality_buffer();
+        let mut encrypted_message = message_buffer_slice[0..blocks_count * BLOCK_SIZE].to_vec();
+        for i in 0..blocks_count {
+            let chunk = &mut encrypted_message[i * BLOCK_SIZE..(i + 1) * BLOCK_SIZE];
+            let block = blocks[i].as_slice();
+            for k in 0..BLOCK_SIZE {
+                chunk[k] ^= block[k];
+            }
+        }
+        self.ghash.update_padded(&encrypted_message);
+        self.message_buffer = message_buffer_slice[blocks_count * BLOCK_SIZE..].to_vec();
+        self.message_len += encrypted_message.len();
 
         encrypted_message
     }
 
     pub fn finalize(&mut self) -> (Vec<u8>, Vec<u8>) {
-        let mut encrypted_message = Vec::with_capacity(16);
+        let mut final_encrypted_message = Vec::with_capacity(BLOCK_SIZE);
         if !self.message_buffer.is_empty() {
-            // last block and this block len is less than 128 bits
+            // last block and this block len may less than 128 bits (16 bytes)
             self.encryption_nonce = inc_32(self.encryption_nonce);
             let mut ctr = self.encryption_nonce.to_be_bytes();
-            let block = Block::<$aesn>::from_mut_slice(&mut ctr);
-            self.crypto.encrypt_block(block);
+            let block = Block::<AesBlock>::from_mut_slice(&mut ctr);
+            self.cipher.encrypt_block(block);
 
             let chunk = self.message_buffer.as_slice();
             let msb = msb_s(chunk.len() * 8, block.as_slice());
             let y = u8to128(chunk) ^ u8to128(&msb);
-            encrypted_message.extend_from_slice(&y.to_be_bytes()[16 - chunk.len()..16]);
-            self.integrality_buffer.extend_from_slice(&encrypted_message);
-            self.message_len += encrypted_message.len();
+            final_encrypted_message.extend_from_slice(&y.to_be_bytes()[16 - chunk.len()..16]);
+            self.ghash.update_padded(&final_encrypted_message);
+            self.message_len += final_encrypted_message.len();
         }
         let adata_bit_len = self.adata_len * 8;
         let message_bit_len = self.message_len * 8;
-        let u = 128 * ((message_bit_len + 128 - 1) / 128) - message_bit_len;
-        self.integrality_buffer.extend_from_slice(&vec![0x00; u / 8]);
-        self.integrality_buffer.extend_from_slice(&(adata_bit_len as u64).to_be_bytes());
-        self.integrality_buffer.extend_from_slice(&(message_bit_len as u64).to_be_bytes());
+        let mut adata_and_message_len = Vec::with_capacity(BLOCK_SIZE);
+        adata_and_message_len.extend_from_slice(&(adata_bit_len as u64).to_be_bytes());
+        adata_and_message_len.extend_from_slice(&(message_bit_len as u64).to_be_bytes());
+        self.ghash.update_padded(&adata_and_message_len);
 
-        self.update_integrality_buffer();
-        assert!(self.integrality_buffer.is_empty());
 
-        let tag = self.calculate_tag();
+        let tag = self.compute_tag();
 
-        (encrypted_message, tag)
+        (final_encrypted_message, tag)
     }
 
-    fn calculate_tag(&mut self) -> Vec<u8> {
+    fn compute_tag(&mut self) -> Vec<u8> {
         let mut bs = self.init_nonce.to_be_bytes().clone();
-        let block = Block::<$aesn>::from_mut_slice(&mut bs);
-        self.crypto.encrypt_block(block);
-        let tag_trunk = self.ghash_val.to_be_bytes();
+        let block = Block::<AesBlock>::from_mut_slice(&mut bs);
+        self.cipher.encrypt_block(block);
+        let ghash = self.ghash.clone().finalize();
+        let tag_trunk = ghash.as_slice();
         let y = u8to128(&tag_trunk) ^ u8to128(&block.as_slice());
         y.to_be_bytes().to_vec()
     }
 
-    fn update_integrality_buffer(&mut self) {
-        let integrality_buffer_slice = self.integrality_buffer.as_slice();
-        let integrality_buffer_slice_len = integrality_buffer_slice.len();
-        if integrality_buffer_slice_len >= 16 {
-            let blocks_count = integrality_buffer_slice_len / 16;
-            for i in 0..blocks_count {
-                let buf = &integrality_buffer_slice[i * 16..(i + 1) * 16];
-                self.ghash_val = gmul_128(self.ghash_val ^ u8to128(buf), self.ghash_key)
-            }
-            self.integrality_buffer = integrality_buffer_slice[blocks_count * 16..].to_vec();
-        }
-    }
-
     fn ghash_key(&mut self) -> u128 {
-        let mut block = [0u8; 16];
-        let block = Block::<$aesn>::from_mut_slice(&mut block);
-        self.crypto.encrypt_block(block);
+        let mut block = [0u8; BLOCK_SIZE];
+        let block = Block::<AesBlock>::from_mut_slice(&mut block);
+        self.cipher.encrypt_block(block);
         u8to128(&block.as_slice())
     }
 

src/lib.rs

@@ -198,6 +198,7 @@ fn test256() {
     ];
 
     for (key, nonce, aad, plaintext) in knp {
+        println!("======= {} {} {} {}", hex::encode(key), hex::encode(nonce), hex::encode(aad), hex::encode(plaintext));
         // encrypt
         let mut ciphertext = vec![];
         let mut encryptor = Aes256GcmStreamEncryptor::new(key.clone(), &nonce);
@@ -248,7 +249,7 @@ fn test256_stream() {
     // encrypt
     let mut ciphertext = vec![];
     let mut encryptor = Aes256GcmStreamEncryptor::new(key.clone(), &nonce);
-    for i in 0..1024 {
+    for i in 0..1025 {
         plaintext.extend_from_slice(&[(i % 128) as u8]);
         ciphertext.extend_from_slice(&encryptor.update(&[(i % 128) as u8]));
     }

src/util.rs

@@ -1,3 +1,15 @@
+use cipher::BlockSizeUser;
+use cipher::consts::U16;
+
+pub(crate) struct AesBlock {}
+
+impl BlockSizeUser for AesBlock {
+    type BlockSize = U16;
+}
+
+pub(crate) const BLOCK_SIZE: usize = 16;
+
+
 // R = 11100001 || 0(120)
 const R: u128 = 0b11100001 << 120;