Merge pull request #77 from Florob/cleanup

Cleanup

Author: cosmycoder

src/rust-crypto/cryptoutil.rs

@@ -9,7 +9,6 @@
 // except according to those terms.
 
 use std;
-use std::mem;
 use std::num::{One, Zero, CheckedAdd};
 use std::slice::bytes::{MutableByteVector, copy_memory};
 
@@ -126,62 +125,56 @@ pub fn read_u32_be(input: &[u8]) -> u32 {
 #[cfg(target_arch = "x86")]
 #[cfg(target_arch = "x86_64")]
 #[inline(never)]
-#[allow(unused_variable)]
 #[allow(dead_assignment)]
 unsafe fn fixed_time_eq_asm(mut lhsp: *u8, mut rhsp: *u8, mut count: uint) -> bool {
     let mut result: u8 = 0;
-    let mut tmp: u8 = mem::uninitialized();
 
     asm!(
         "
             fixed_time_eq_loop:
 
-            mov ($1), $4
-            xor ($2), $4
-            or $4, $0
+            mov ($1), %cl
+            xor ($2), %cl
+            or %cl, $0
 
             inc $1
             inc $2
             dec $3
             jnz fixed_time_eq_loop
         "
-        : "=&r" (result), "=&r" (lhsp), "=&r" (rhsp), "=&r" (count), "=&r" (tmp) // output
-        : "0" (result), "1" (lhsp), "2" (rhsp), "3" (count) // input
-        : "cc" // clobbers
-        : // flags
+        : "+r" (result), "+r" (lhsp), "+r" (rhsp), "+r" (count) // all input and output
+        : // input
+        : "cl", "cc" // clobbers
+        : "volatile" // flags
     );
 
     return result == 0;
 }
 
 #[cfg(target_arch = "arm")]
 #[inline(never)]
-#[allow(unused_variable)]
 #[allow(dead_assignment)]
 unsafe fn fixed_time_eq_asm(mut lhsp: *u8, mut rhsp: *u8, mut count: uint) -> bool {
     let mut result: u8 = 0;
-    let mut tmp1: u8 = mem::uninitialized();
-    let mut tmp2: u8 = mem::uninitialized();
 
     asm!(
         "
             fixed_time_eq_loop:
 
-            ldrb $4, [$1]
-            ldrb $5, [$2]
-            eor $4, $4, $5
-            orr $0, $0, $4
+            ldrb r4, [$1]
+            ldrb r5, [$2]
+            eor r4, r4, r5
+            orr $0, $0, r4
 
             add $1, $1, #1
             add $2, $2, #1
             subs $3, $3, #1
             bne fixed_time_eq_loop
         "
-        // output
-        : "=&r" (result), "=&r" (lhsp), "=&r" (rhsp), "=&r" (count), "=&r" (tmp1), "=&r" (tmp2)
-        : "0" (result), "1" (lhsp), "2" (rhsp), "3" (count) // input
-        : "cc" // clobbers
-        : // flags
+        : "+r" (result), "+r" (lhsp), "+r" (rhsp), "+r" (count) // all input and output
+        : // input
+        : "r4", "r5", "cc" // clobbers
+        : "volatile" // flags
     );
 
     return result == 0;

src/rust-crypto/hmac.rs

@@ -37,17 +37,11 @@ fn expand_key<D: Digest>(digest: &mut D, key: &[u8]) -> Vec<u8> {
     let mut expanded_key = Vec::from_elem(bs, 0u8);
     if key.len() <= bs {
         slice::bytes::copy_memory(expanded_key.as_mut_slice(), key);
-        for elem in expanded_key.mut_slice_from(key.len()).mut_iter() {
-            *elem = 0;
-        }
     } else {
         let output_size = digest.output_bytes();
         digest.input(key);
         digest.result(expanded_key.mut_slice_to(output_size));
         digest.reset();
-        for elem in expanded_key.mut_slice_from(output_size).mut_iter() {
-            *elem = 0;
-        }
     }
     return expanded_key;
 }

src/rust-crypto/pbkdf2.rs

@@ -10,7 +10,6 @@
  */
 
 use std::io::IoResult;
-use std::num::Bounded;
 use std::rand::{OsRng, Rng};
 use std::slice::MutableCloneableVector;
 
@@ -94,12 +93,9 @@ pub fn pbkdf2<M: Mac>(mac: &mut M, salt: &[u8], c: u32, output: &mut [u8]) {
     let mut idx: u32 = 0;
 
     for chunk in output.mut_chunks(os) {
-        if idx == Bounded::max_value() {
-            fail!("PBKDF2 size limit exceeded.");
-        } else {
-            // The block index starts at 1. So, this is supposed to run on the first execution.
-            idx += 1;
-        }
+        // The block index starts at 1. So, this is supposed to run on the first execution.
+        idx = idx.checked_add(&1).expect("PBKDF2 size limit exceeded.");
+
         if chunk.len() == os {
             calculate_block(mac, salt, c, idx, scratch.as_mut_slice(), chunk);
         } else {