cryptopals

commit f6818cd7287714e0dc1cb85a43fd0226bb30d3cd
parent 0bac88e3bb33c388147e3446c4b6a186e3fef9dc
Author: Jared Tobin <jared@jtobin.ca>
Date:   Mon, 29 May 2017 19:14:56 +1200

2.10.

Diffstat:
M
docs/s2.md
 | 
7
+++++++
M
lib/aes_cbc/src/main.rs
 | 
11
++++++++---

2 files changed, 15 insertions(+), 3 deletions(-)
diff --git a/docs/s2.md b/docs/s2.md
@@ -17,3 +17,10 @@
 
 The problem description says NO OPENSSL, but heck them rules AMIRITE?
 
+Ok here's an answer that I had to write code to get:
+
+    $ cat data/s2/q10_input.txt | tr -d '\n' | \
+        ./bin/aes_cbc --key "YELLOW SUBMARINE" | head -2
+    I'm back and I'm ringin' the bell
+    A rockin' on the mike while the fly girls yell
+
diff --git a/lib/aes_cbc/src/main.rs b/lib/aes_cbc/src/main.rs
@@ -25,10 +25,11 @@ fn new_crypter_unpadded(
         key: &[u8],
         iv: Option<&[u8]>
         ) -> Crypter {
+    assert!(key.len() == 16);
 
     let mut crypter = match Crypter::new(cipher, mode, key, iv) {
             Ok(val) => val,
-            Err(err) => panic!("{}", err)
+            Err(err) => panic!("{} - key len {}", err, key.len())
     };
 
     crypter.pad(false);
@@ -37,6 +38,8 @@ fn new_crypter_unpadded(
 }
 
 fn ecb_128_crypt(mode: Mode, key: &[u8], text: &[u8]) -> Vec<u8> {
+    assert!(text.len() % 16 == 0);
+
     let cipher = Cipher::aes_128_ecb();
     let iv     = None;
 
@@ -60,6 +63,8 @@ fn ecb_128_decrypt(key: &[u8], text: &[u8]) -> Vec<u8> {
 }
 
 fn cbc_128_encrypt(key: &[u8], text: &[u8], iv: Vec<u8>) -> Vec<u8> {
+    assert!(iv.len() == 16);
+
     let mut iv = iv;
     let mut ciphertext = Vec::with_capacity(text.len());
 
@@ -140,8 +145,8 @@ fn main() {
     };
 
     let output = match mode {
-            Mode::Decrypt => cbc_128_decrypt(&decoded[..], key, iv),
-            Mode::Encrypt => cbc_128_encrypt(&decoded[..], key, iv),
+            Mode::Decrypt => cbc_128_decrypt(key, &decoded[..], iv),
+            Mode::Encrypt => cbc_128_encrypt(key, &decoded[..], iv),
     };
 
     match mode {