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Remove dead code from cryptoutil.rs and remove macro_rules feature flag.
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Palmer Cox committed Oct 28, 2013
1 parent 72a9482 commit ca13200
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Showing 2 changed files with 73 additions and 230 deletions.
301 changes: 72 additions & 229 deletions src/librustpkg/cryptoutil.rs
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Expand Up @@ -8,22 +8,10 @@
// option. This file may not be copied, modified, or distributed
// except according to those terms.

use std::num::{One, Zero, CheckedAdd};
use std::num::{Zero, CheckedAdd};
use std::vec::bytes::{MutableByteVector, copy_memory};


/// Write a u64 into a vector, which must be 8 bytes long. The value is written in big-endian
/// format.
pub fn write_u64_be(dst: &mut[u8], input: u64) {
use std::cast::transmute;
use std::unstable::intrinsics::to_be64;
assert!(dst.len() == 8);
unsafe {
let x: *mut i64 = transmute(dst.unsafe_mut_ref(0));
*x = to_be64(input as i64);
}
}

/// Write a u32 into a vector, which must be 4 bytes long. The value is written in big-endian
/// format.
pub fn write_u32_be(dst: &mut[u8], input: u32) {
Expand All @@ -36,34 +24,6 @@ pub fn write_u32_be(dst: &mut[u8], input: u32) {
}
}

/// Write a u32 into a vector, which must be 4 bytes long. The value is written in little-endian
/// format.
pub fn write_u32_le(dst: &mut[u8], input: u32) {
use std::cast::transmute;
use std::unstable::intrinsics::to_le32;
assert!(dst.len() == 4);
unsafe {
let x: *mut i32 = transmute(dst.unsafe_mut_ref(0));
*x = to_le32(input as i32);
}
}

/// Read a vector of bytes into a vector of u64s. The values are read in big-endian format.
pub fn read_u64v_be(dst: &mut[u64], input: &[u8]) {
use std::cast::transmute;
use std::unstable::intrinsics::to_be64;
assert!(dst.len() * 8 == input.len());
unsafe {
let mut x: *mut i64 = transmute(dst.unsafe_mut_ref(0));
let mut y: *i64 = transmute(input.unsafe_ref(0));
do dst.len().times() {
*x = to_be64(*y);
x = x.offset(1);
y = y.offset(1);
}
}
}

/// Read a vector of bytes into a vector of u32s. The values are read in big-endian format.
pub fn read_u32v_be(dst: &mut[u32], input: &[u8]) {
use std::cast::transmute;
Expand All @@ -80,22 +40,6 @@ pub fn read_u32v_be(dst: &mut[u32], input: &[u8]) {
}
}

/// Read a vector of bytes into a vector of u32s. The values are read in little-endian format.
pub fn read_u32v_le(dst: &mut[u32], input: &[u8]) {
use std::cast::transmute;
use std::unstable::intrinsics::to_le32;
assert!(dst.len() * 4 == input.len());
unsafe {
let mut x: *mut i32 = transmute(dst.unsafe_mut_ref(0));
let mut y: *i32 = transmute(input.unsafe_ref(0));
do dst.len().times() {
*x = to_le32(*y);
x = x.offset(1);
y = y.offset(1);
}
}
}


trait ToBits {
/// Convert the value in bytes to the number of bits, a tuple where the 1st item is the
Expand Down Expand Up @@ -124,51 +68,6 @@ pub fn add_bytes_to_bits<T: Int + CheckedAdd + ToBits>(bits: T, bytes: T) -> T {
}
}

/// Adds the specified number of bytes to the bit count, which is a tuple where the first element is
/// the high order value. fail!() if this would cause numeric overflow.
pub fn add_bytes_to_bits_tuple
<T: Int + Unsigned + CheckedAdd + ToBits>
(bits: (T, T), bytes: T) -> (T, T) {
let (new_high_bits, new_low_bits) = bytes.to_bits();
let (hi, low) = bits;

// Add the low order value - if there is no overflow, then add the high order values
// If the addition of the low order values causes overflow, add one to the high order values
// before adding them.
match low.checked_add(&new_low_bits) {
Some(x) => {
if new_high_bits == Zero::zero() {
// This is the fast path - every other alternative will rarely occur in practice
// considering how large an input would need to be for those paths to be used.
return (hi, x);
} else {
match hi.checked_add(&new_high_bits) {
Some(y) => return (y, x),
None => fail!("Numeric overflow occured.")
}
}
},
None => {
let one: T = One::one();
let z = match new_high_bits.checked_add(&one) {
Some(w) => w,
None => fail!("Numeric overflow occured.")
};
match hi.checked_add(&z) {
// This re-executes the addition that was already performed earlier when overflow
// occured, this time allowing the overflow to happen. Technically, this could be
// avoided by using the checked add intrinsic directly, but that involves using
// unsafe code and is not really worthwhile considering how infrequently code will
// run in practice. This is the reason that this function requires that the type T
// be Unsigned - overflow is not defined for Signed types. This function could be
// implemented for signed types as well if that were needed.
Some(y) => return (y, low + new_low_bits),
None => fail!("Numeric overflow occured.")
}
}
}
}


/// A FixedBuffer, likes its name implies, is a fixed size buffer. When the buffer becomes full, it
/// must be processed. The input() method takes care of processing and then clearing the buffer
Expand Down Expand Up @@ -204,83 +103,6 @@ pub trait FixedBuffer {
fn size(&self) -> uint;
}

macro_rules! impl_fixed_buffer( ($name:ident, $size:expr) => (
impl FixedBuffer for $name {
fn input(&mut self, input: &[u8], func: &fn(&[u8])) {
let mut i = 0;

// FIXME: #6304 - This local variable shouldn't be necessary.
let size = $size;

// If there is already data in the buffer, copy as much as we can into it and process
// the data if the buffer becomes full.
if self.buffer_idx != 0 {
let buffer_remaining = size - self.buffer_idx;
if input.len() >= buffer_remaining {
copy_memory(
self.buffer.mut_slice(self.buffer_idx, size),
input.slice_to(buffer_remaining),
buffer_remaining);
self.buffer_idx = 0;
func(self.buffer);
i += buffer_remaining;
} else {
copy_memory(
self.buffer.mut_slice(self.buffer_idx, self.buffer_idx + input.len()),
input,
input.len());
self.buffer_idx += input.len();
return;
}
}

// While we have at least a full buffer size chunks's worth of data, process that data
// without copying it into the buffer
while input.len() - i >= size {
func(input.slice(i, i + size));
i += size;
}

// Copy any input data into the buffer. At this point in the method, the ammount of
// data left in the input vector will be less than the buffer size and the buffer will
// be empty.
let input_remaining = input.len() - i;
copy_memory(
self.buffer.mut_slice(0, input_remaining),
input.slice_from(i),
input.len() - i);
self.buffer_idx += input_remaining;
}

fn reset(&mut self) {
self.buffer_idx = 0;
}

fn zero_until(&mut self, idx: uint) {
assert!(idx >= self.buffer_idx);
self.buffer.mut_slice(self.buffer_idx, idx).set_memory(0);
self.buffer_idx = idx;
}

fn next<'s>(&'s mut self, len: uint) -> &'s mut [u8] {
self.buffer_idx += len;
return self.buffer.mut_slice(self.buffer_idx - len, self.buffer_idx);
}

fn full_buffer<'s>(&'s mut self) -> &'s [u8] {
assert!(self.buffer_idx == $size);
self.buffer_idx = 0;
return self.buffer.slice_to($size);
}

fn position(&self) -> uint { self.buffer_idx }

fn remaining(&self) -> uint { $size - self.buffer_idx }

fn size(&self) -> uint { $size }
}
))


/// A fixed size buffer of 64 bytes useful for cryptographic operations.
pub struct FixedBuffer64 {
Expand All @@ -298,25 +120,80 @@ impl FixedBuffer64 {
}
}

impl_fixed_buffer!(FixedBuffer64, 64)
impl FixedBuffer for FixedBuffer64 {
fn input(&mut self, input: &[u8], func: &fn(&[u8])) {
let mut i = 0;

/// A fixed size buffer of 128 bytes useful for cryptographic operations.
pub struct FixedBuffer128 {
priv buffer: [u8, ..128],
priv buffer_idx: uint,
}
// FIXME: #6304 - This local variable shouldn't be necessary.
let size = 64;

impl FixedBuffer128 {
/// Create a new buffer
pub fn new() -> FixedBuffer128 {
return FixedBuffer128 {
buffer: [0u8, ..128],
buffer_idx: 0
};
// If there is already data in the buffer, copy as much as we can into it and process
// the data if the buffer becomes full.
if self.buffer_idx != 0 {
let buffer_remaining = size - self.buffer_idx;
if input.len() >= buffer_remaining {
copy_memory(
self.buffer.mut_slice(self.buffer_idx, size),
input.slice_to(buffer_remaining),
buffer_remaining);
self.buffer_idx = 0;
func(self.buffer);
i += buffer_remaining;
} else {
copy_memory(
self.buffer.mut_slice(self.buffer_idx, self.buffer_idx + input.len()),
input,
input.len());
self.buffer_idx += input.len();
return;
}
}

// While we have at least a full buffer size chunks's worth of data, process that data
// without copying it into the buffer
while input.len() - i >= size {
func(input.slice(i, i + size));
i += size;
}

// Copy any input data into the buffer. At this point in the method, the ammount of
// data left in the input vector will be less than the buffer size and the buffer will
// be empty.
let input_remaining = input.len() - i;
copy_memory(
self.buffer.mut_slice(0, input_remaining),
input.slice_from(i),
input.len() - i);
self.buffer_idx += input_remaining;
}

fn reset(&mut self) {
self.buffer_idx = 0;
}

fn zero_until(&mut self, idx: uint) {
assert!(idx >= self.buffer_idx);
self.buffer.mut_slice(self.buffer_idx, idx).set_memory(0);
self.buffer_idx = idx;
}

fn next<'s>(&'s mut self, len: uint) -> &'s mut [u8] {
self.buffer_idx += len;
return self.buffer.mut_slice(self.buffer_idx - len, self.buffer_idx);
}
}

impl_fixed_buffer!(FixedBuffer128, 128)
fn full_buffer<'s>(&'s mut self) -> &'s [u8] {
assert!(self.buffer_idx == 64);
self.buffer_idx = 0;
return self.buffer.slice_to(64);
}

fn position(&self) -> uint { self.buffer_idx }

fn remaining(&self) -> uint { 64 - self.buffer_idx }

fn size(&self) -> uint { 64 }
}


/// The StandardPadding trait adds a method useful for various hash algorithms to a FixedBuffer
Expand Down Expand Up @@ -351,7 +228,7 @@ pub mod test {
use std::vec;
use extra::hex::FromHex;

use cryptoutil::{add_bytes_to_bits, add_bytes_to_bits_tuple};
use cryptoutil::add_bytes_to_bits;
use digest::Digest;

/// Feed 1,000,000 'a's into the digest with varying input sizes and check that the result is
Expand Down Expand Up @@ -391,38 +268,4 @@ pub mod test {
fn test_add_bytes_to_bits_overflow() {
add_bytes_to_bits::<u64>(Bounded::max_value(), 1);
}

// A normal addition - no overflow occurs (fast path)
#[test]
fn test_add_bytes_to_bits_tuple_ok() {
assert!(add_bytes_to_bits_tuple::<u64>((5, 100), 10) == (5, 180));
}

// The low order value overflows into the high order value
#[test]
fn test_add_bytes_to_bits_tuple_ok2() {
assert!(add_bytes_to_bits_tuple::<u64>((5, Bounded::max_value()), 1) == (6, 7));
}

// The value to add is too large to be converted into bits without overflowing its type
#[test]
fn test_add_bytes_to_bits_tuple_ok3() {
assert!(add_bytes_to_bits_tuple::<u64>((5, 0), 0x4000000000000001) == (7, 8));
}

// A simple failure case - adding 1 to the max value
#[test]
#[should_fail]
fn test_add_bytes_to_bits_tuple_overflow() {
add_bytes_to_bits_tuple::<u64>((Bounded::max_value(), Bounded::max_value()), 1);
}

// The value to add is too large to convert to bytes without overflowing its type, but the high
// order value from this conversion overflows when added to the existing high order value
#[test]
#[should_fail]
fn test_add_bytes_to_bits_tuple_overflow2() {
let value: u64 = Bounded::max_value();
add_bytes_to_bits_tuple::<u64>((value - 1, 0), 0x8000000000000000);
}
}
2 changes: 1 addition & 1 deletion src/librustpkg/rustpkg.rs
View file
Expand Up @@ -18,7 +18,7 @@
#[license = "MIT/ASL2"];
#[crate_type = "lib"];

#[feature(globs, managed_boxes, macro_rules)];
#[feature(globs, managed_boxes)];

extern mod extra;
extern mod rustc;
Expand Down

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