MD5: Create an implementation of MD5.

Author: Palmer Cox

src/libextra/crypto/md5.rs

@@ -0,0 +1,329 @@
+// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use std::uint;
+
+use cryptoutil::{write_u32_le, read_u32v_le, FixedBuffer, FixedBuffer64, StandardPadding};
+use digest::Digest;
+
+
+// A structure that represents that state of a digest computation for the MD5 digest function
+struct Md5State {
+    s0: u32,
+    s1: u32,
+    s2: u32,
+    s3: u32
+}
+
+impl Md5State {
+    fn new() -> Md5State {
+        return Md5State {
+            s0: 0x67452301,
+            s1: 0xefcdab89,
+            s2: 0x98badcfe,
+            s3: 0x10325476
+        };
+    }
+
+    fn reset(&mut self) {
+        self.s0 = 0x67452301;
+        self.s1 = 0xefcdab89;
+        self.s2 = 0x98badcfe;
+        self.s3 = 0x10325476;
+    }
+
+    fn process_block(&mut self, input: &[u8]) {
+        fn f(u: u32, v: u32, w: u32) -> u32 {
+            return (u & v) | (!u & w);
+        }
+
+        fn g(u: u32, v: u32, w: u32) -> u32 {
+            return (u & w) | (v & !w);
+        }
+
+        fn h(u: u32, v: u32, w: u32) -> u32 {
+            return u ^ v ^ w;
+        }
+
+        fn i(u: u32, v: u32, w: u32) -> u32 {
+            return v ^ (u | !w);
+        }
+
+        fn rotate_left(x: u32, n: u32) -> u32 {
+            return (x << n) | (x >> (32 - n));
+        }
+
+        fn op_f(w: u32, x: u32, y: u32, z: u32, m: u32, s: u32) -> u32 {
+            return rotate_left(w + f(x, y, z) + m, s) + x;
+        }
+
+        fn op_g(w: u32, x: u32, y: u32, z: u32, m: u32, s: u32) -> u32 {
+            return rotate_left(w + g(x, y, z) + m, s) + x;
+        }
+
+        fn op_h(w: u32, x: u32, y: u32, z: u32, m: u32, s: u32) -> u32 {
+            return rotate_left(w + h(x, y, z) + m, s) + x;
+        }
+
+        fn op_i(w: u32, x: u32, y: u32, z: u32, m: u32, s: u32) -> u32 {
+            return rotate_left(w + i(x, y, z) + m, s) + x;
+        }
+
+        let mut a = self.s0;
+        let mut b = self.s1;
+        let mut c = self.s2;
+        let mut d = self.s3;
+
+        let mut data = [0u32, ..16];
+
+        read_u32v_le(data, input);
+
+        // round 1
+        do uint::range_step(0, 16, 4) |i| {
+            a = op_f(a, b, c, d, data[i] + C1[i], 7);
+            d = op_f(d, a, b, c, data[i + 1] + C1[i + 1], 12);
+            c = op_f(c, d, a, b, data[i + 2] + C1[i + 2], 17);
+            b = op_f(b, c, d, a, data[i + 3] + C1[i + 3], 22);
+            true
+        };
+
+        // round 2
+        let mut t = 1;
+        do uint::range_step(0, 16, 4) |i| {
+            a = op_g(a, b, c, d, data[t & 0x0f] + C2[i], 5);
+            d = op_g(d, a, b, c, data[(t + 5) & 0x0f] + C2[i + 1], 9);
+            c = op_g(c, d, a, b, data[(t + 10) & 0x0f] + C2[i + 2], 14);
+            b = op_g(b, c, d, a, data[(t + 15) & 0x0f] + C2[i + 3], 20);
+            t += 20;
+            true
+        };
+
+        // round 3
+        t = 5;
+        do uint::range_step(0, 16, 4) |i| {
+            a = op_h(a, b, c, d, data[t & 0x0f] + C3[i], 4);
+            d = op_h(d, a, b, c, data[(t + 3) & 0x0f] + C3[i + 1], 11);
+            c = op_h(c, d, a, b, data[(t + 6) & 0x0f] + C3[i + 2], 16);
+            b = op_h(b, c, d, a, data[(t + 9) & 0x0f] + C3[i + 3], 23);
+            t += 12;
+            true
+        };
+
+        // round 4
+        t = 0;
+        do uint::range_step(0, 16, 4) |i| {
+            a = op_i(a, b, c, d, data[t & 0x0f] + C4[i], 6);
+            d = op_i(d, a, b, c, data[(t + 7) & 0x0f] + C4[i + 1], 10);
+            c = op_i(c, d, a, b, data[(t + 14) & 0x0f] + C4[i + 2], 15);
+            b = op_i(b, c, d, a, data[(t + 21) & 0x0f] + C4[i + 3], 21);
+            t += 28;
+            true
+        };
+
+        self.s0 += a;
+        self.s1 += b;
+        self.s2 += c;
+        self.s3 += d;
+    }
+}
+
+// Round 1 constants
+static C1: [u32, ..16] = [
+    0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee, 0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501,
+    0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be, 0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821
+];
+
+// Round 2 constants
+static C2: [u32, ..16] = [
+    0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa, 0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8,
+    0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed, 0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a
+];
+
+// Round 3 constants
+static C3: [u32, ..16] = [
+    0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c, 0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70,
+    0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x04881d05, 0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665
+];
+
+// Round 4 constants
+static C4: [u32, ..16] = [
+    0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039, 0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1,
+    0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1, 0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391
+];
+
+
+/// The MD5 Digest algorithm
+struct Md5 {
+    priv length_bytes: u64,
+    priv buffer: FixedBuffer64,
+    priv state: Md5State,
+    priv finished: bool,
+}
+
+impl Md5 {
+    /// Construct a new instance of the MD5 Digest.
+    pub fn new() -> Md5 {
+        return Md5 {
+            length_bytes: 0,
+            buffer: FixedBuffer64::new(),
+            state: Md5State::new(),
+            finished: false
+        }
+    }
+}
+
+impl Digest for Md5 {
+    fn input(&mut self, input: &[u8]) {
+        assert!(!self.finished);
+        // Unlike Sha1 and Sha2, the length value in MD5 is defined as the length of the message mod
+        // 2^64 - ie: integer overflow is OK.
+        self.length_bytes += input.len() as u64;
+        self.buffer.input(input, |d: &[u8]| { self.state.process_block(d); });
+    }
+
+    fn reset(&mut self) {
+        self.length_bytes = 0;
+        self.buffer.reset();
+        self.state.reset();
+        self.finished = false;
+    }
+
+    fn result(&mut self, out: &mut [u8]) {
+        if !self.finished {
+            self.buffer.standard_padding(8, |d: &[u8]| { self.state.process_block(d); });
+            write_u32_le(self.buffer.next(4), (self.length_bytes << 3) as u32);
+            write_u32_le(self.buffer.next(4), (self.length_bytes >> 29) as u32);
+            self.state.process_block(self.buffer.full_buffer());
+            self.finished = true;
+        }
+
+        write_u32_le(out.mut_slice(0, 4), self.state.s0);
+        write_u32_le(out.mut_slice(4, 8), self.state.s1);
+        write_u32_le(out.mut_slice(8, 12), self.state.s2);
+        write_u32_le(out.mut_slice(12, 16), self.state.s3);
+    }
+
+    fn output_bits(&self) -> uint { 128 }
+}
+
+
+#[cfg(test)]
+mod tests {
+    use cryptoutil::test::test_digest_1million_random;
+    use digest::Digest;
+    use md5::Md5;
+
+
+    struct Test {
+        input: ~str,
+        output_str: ~str,
+    }
+
+    fn test_hash<D: Digest>(sh: &mut D, tests: &[Test]) {
+        // Test that it works when accepting the message all at once
+        for t in tests.iter() {
+            sh.input_str(t.input);
+
+            let out_str = sh.result_str();
+            assert!(out_str == t.output_str);
+
+            sh.reset();
+        }
+
+        // Test that it works when accepting the message in pieces
+        for t in tests.iter() {
+            let len = t.input.len();
+            let mut left = len;
+            while left > 0u {
+                let take = (left + 1u) / 2u;
+                sh.input_str(t.input.slice(len - left, take + len - left));
+                left = left - take;
+            }
+
+            let out_str = sh.result_str();
+            assert!(out_str == t.output_str);
+
+            sh.reset();
+        }
+    }
+
+    #[test]
+    fn test_md5() {
+        // Examples from wikipedia
+        let wikipedia_tests = ~[
+            Test {
+                input: ~"",
+                output_str: ~"d41d8cd98f00b204e9800998ecf8427e"
+            },
+            Test {
+                input: ~"The quick brown fox jumps over the lazy dog",
+                output_str: ~"9e107d9d372bb6826bd81d3542a419d6"
+            },
+            Test {
+                input: ~"The quick brown fox jumps over the lazy dog.",
+                output_str: ~"e4d909c290d0fb1ca068ffaddf22cbd0"
+            },
+        ];
+
+        let tests = wikipedia_tests;
+
+        let mut sh = Md5::new();
+
+        test_hash(&mut sh, tests);
+    }
+
+    #[test]
+    fn test_1million_random_md5() {
+        let mut sh = Md5::new();
+        test_digest_1million_random(
+            &mut sh,
+            64,
+            "7707d6ae4e027c70eea2a935c2296f21");
+    }
+}
+
+
+#[cfg(test)]
+mod bench {
+    use extra::test::BenchHarness;
+
+    use md5::Md5;
+
+
+    #[bench]
+    pub fn md5_10(bh: & mut BenchHarness) {
+        let mut sh = Md5::new();
+        let bytes = [1u8, ..10];
+        do bh.iter {
+            sh.input(bytes);
+        }
+        bh.bytes = bytes.len() as u64;
+    }
+
+    #[bench]
+    pub fn md5_1k(bh: & mut BenchHarness) {
+        let mut sh = Md5::new();
+        let bytes = [1u8, ..1024];
+        do bh.iter {
+            sh.input(bytes);
+        }
+        bh.bytes = bytes.len() as u64;
+    }
+
+    #[bench]
+    pub fn md5_64k(bh: & mut BenchHarness) {
+        let mut sh = Md5::new();
+        let bytes = [1u8, ..65536];
+        do bh.iter {
+            sh.input(bytes);
+        }
+        bh.bytes = bytes.len() as u64;
+    }
+}

src/libextra/extra.rs

@@ -71,6 +71,8 @@ pub mod treemap;
 mod cryptoutil;
 #[path="crypto/digest.rs"]
 pub mod digest;
+#[path="crypto/md5.rs"]
+pub mod md5;
 #[path="crypto/sha1.rs"]
 pub mod sha1;
 #[path="crypto/sha2.rs"]