cryptopals

commit 82199b959a615099180a4ba71867a76735b35fb4
parent 9e353091275011ee2b74f13ccea30e21d65ddcdb
Author: Jared Tobin <jared@jtobin.ca>
Date:   Fri, 19 May 2017 18:31:00 +1200

Misc fixes.

Diffstat:
M
docs/s1.md
 | 
4
+---
M
lib/aes_ecb/src/main.rs
 | 
30
+++++++++++++++++++++---------

2 files changed, 22 insertions(+), 12 deletions(-)
diff --git a/docs/s1.md b/docs/s1.md
@@ -156,11 +156,9 @@ I like openssl, heck the rules:
 Alternatively:
 
     $ cat data/s1/q7_input.txt | tr -d '\n' | ./bin/aes_ecb | head -2
-    'm back and I'm ringin' the bell
+    I'm back and I'm ringin' the bell
     A rockin' on the mike while the fly girls yell
 
-NB. missing the initial 'I' there for some reason.
-
 #### 1.8
 
     $ cat data/s1/q8_input.txt | parallel \
diff --git a/lib/aes_ecb/src/main.rs b/lib/aes_ecb/src/main.rs
@@ -5,6 +5,24 @@ extern crate openssl;
 use openssl::symm::{Cipher, Crypter, Mode};
 use std::io::{self, Read};
 
+fn new_crypter_unpadded(
+        cipher: Cipher,
+        mode: Mode,
+        key: &[u8],
+        iv: Option<&[u8]>
+        ) -> Crypter {
+    let mut crypter = match Crypter::new(cipher, mode, key, iv) {
+            Ok(val) => val,
+            Err(err) => panic!("{}", err)
+    };
+
+    crypter.pad(false);
+
+    crypter
+}
+
+// FIXME better command line args
+
 fn main() {
     let mut buffer = String::new();
 
@@ -22,21 +40,15 @@ fn main() {
     let key    = b"YELLOW SUBMARINE";
     let iv     = None;
 
-    let mut crypter = match Crypter::new(cipher, mode, key, iv) {
-            Ok(val) => val,
-            Err(err) => panic!("{}", err)
-    };
-
-    crypter.pad(false);
-
-    let mut result = vec![0u8; decoded_len + cipher.key_len()];
+    let mut crypter = new_crypter_unpadded(cipher, mode, key, iv);
+    let mut result  = vec![0u8; decoded_len + cipher.key_len()];
 
     let decrypted_len = match crypter.update(&decoded, result.as_mut_slice()) {
             Ok(val)  => val,
             Err(err) => panic!("{}", err)
     };
 
-    let output = &result[1..decrypted_len];
+    let output = &result[0..decrypted_len];
 
     println!("{}", String::from_utf8_lossy(output));
 }