impl IvState for cfb-mode

RustCrypto · Feb 6, 2022 · ff23e5c · ff23e5c
1 parent 102b20d
commit ff23e5c
Show file tree

Hide file tree

Showing 3 changed files with 28 additions and 25 deletions.
diff --git a/cfb-mode/src/decrypt.rs b/cfb-mode/src/decrypt.rs
@@ -2,8 +2,9 @@ use cipher::{
     crypto_common::{InnerUser, IvSizeUser},
     generic_array::{ArrayLength, GenericArray},
     inout::InOut,
-    AlgorithmName, AsyncStreamCipher, Block, BlockBackend, BlockCipher, BlockClosure,
-    BlockDecryptMut, BlockEncryptMut, BlockSizeUser, InnerIvInit, Iv, ParBlocks, ParBlocksSizeUser,
+    AlgorithmName, AsyncStreamCipher, Block, BlockBackend, BlockCipher, BlockClosure, BlockDecrypt,
+    BlockDecryptMut, BlockEncryptMut, BlockSizeUser, InnerIvInit, Iv, IvState, ParBlocks,
+    ParBlocksSizeUser,
 };
 use core::fmt;
 
@@ -65,15 +66,17 @@ where
     }
 }
 
-// impl<C> IvState for Decryptor<C>
-// where
-//     C: BlockEncryptMut + BlockDecryptMut + BlockCipher,
-// {
-//     #[inline]
-//     fn iv_state(&self) -> Iv<Self> {
-//         self.iv.clone()
-//     }
-// }
+impl<C> IvState for Decryptor<C>
+where
+    C: BlockEncryptMut + BlockDecrypt + BlockCipher,
+{
+    #[inline]
+    fn iv_state(&self) -> Iv<Self> {
+        let mut res = self.iv.clone();
+        self.cipher.decrypt_block(&mut res);
+        res
+    }
+}
 
 impl<C> AlgorithmName for Decryptor<C>
 where

diff --git a/cfb-mode/src/encrypt.rs b/cfb-mode/src/encrypt.rs
@@ -3,8 +3,8 @@ use cipher::{
     crypto_common::{InnerUser, IvSizeUser},
     generic_array::{ArrayLength, GenericArray},
     inout::InOut,
-    AlgorithmName, AsyncStreamCipher, Block, BlockBackend, BlockCipher, BlockClosure,
-    BlockEncryptMut, BlockSizeUser, InnerIvInit, Iv, ParBlocksSizeUser,
+    AlgorithmName, AsyncStreamCipher, Block, BlockBackend, BlockCipher, BlockClosure, BlockDecrypt,
+    BlockEncryptMut, BlockSizeUser, InnerIvInit, Iv, IvState, ParBlocksSizeUser,
 };
 use core::fmt;
 
@@ -66,15 +66,17 @@ where
     }
 }
 
-// impl<C> IvState for Encryptor<C>
-// where
-//     C: BlockEncryptMut + BlockCipher,
-// {
-//     #[inline]
-//     fn iv_state(&self) -> Iv<Self> {
-//         self.iv.clone()
-//     }
-// }
+impl<C> IvState for Encryptor<C>
+where
+    C: BlockEncryptMut + BlockDecrypt + BlockCipher,
+{
+    #[inline]
+    fn iv_state(&self) -> Iv<Self> {
+        let mut res = self.iv.clone();
+        self.cipher.decrypt_block(&mut res);
+        res
+    }
+}
 
 impl<C> AlgorithmName for Encryptor<C>
 where

diff --git a/cfb-mode/tests/aes.rs b/cfb-mode/tests/aes.rs
@@ -1,15 +1,13 @@
 use aes::*;
 use cfb_mode::{Decryptor, Encryptor};
-use cipher::{block_mode_dec_test, block_mode_enc_test};
+use cipher::{block_mode_dec_test, block_mode_enc_test, iv_state_test};
 
-/*
 iv_state_test!(aes128_cfb_enc_iv_state, Encryptor<Aes128>, encrypt);
 iv_state_test!(aes128_cfb_dec_iv_state, Decryptor<Aes128>, decrypt);
 iv_state_test!(aes192_cfb_enc_iv_state, Encryptor<Aes192>, encrypt);
 iv_state_test!(aes192_cfb_dec_iv_state, Decryptor<Aes192>, decrypt);
 iv_state_test!(aes256_cfb_enc_iv_state, Encryptor<Aes256>, encrypt);
 iv_state_test!(aes256_cfb_dec_iv_state, Decryptor<Aes256>, decrypt);
-*/
 
 // Test vectors from CVAP "AES Multiblock Message Test (MMT) Sample Vectors":
 // <https://csrc.nist.gov/Projects/Cryptographic-Algorithm-Validation-Program/Block-Ciphers>