Add support for HMAC, RC4, AES-128, hex encoding, etc

1 files changed, 91 insertions, 0 deletions

diff --git a/hex.rs b/hex.rs
new file mode 100644
index 00000000..ca422a49
--- /dev/null
+++ b/hex.rs
@@ -0,0 +1,91 @@
+/*
+ * Copyright 2013 Jack Lloyd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+extern mod std;
+
+pub trait ToHex {
+    pure fn to_hex() -> ~str;
+}
+
+impl &[u8]: ToHex {
+    pure fn to_hex() -> ~str {
+
+        let chars = str::chars(~"0123456789ABCDEF");
+
+        let mut s = ~"";
+
+        for uint::range(0, self.len()) |i| {
+
+            let x = self[i];
+
+            let xhi = (x >> 4) & 0x0F;
+            let xlo = (x     ) & 0x0F;
+
+            unsafe {
+                str::push_char(&mut s, chars[xhi]);
+                str::push_char(&mut s, chars[xlo]);
+            }
+        }
+
+        s
+    }
+}
+
+pub trait FromHex {
+    pure fn from_hex() -> ~[u8];
+}
+
+impl &str: FromHex {
+    pure fn from_hex() -> ~[u8] {
+        let mut vec = vec::with_capacity(self.len() / 2);
+
+        for str::each_chari(self) |i,c| {
+
+            let nibble =
+                if c >= '0' && c <= '9' { (c as u8) - 0x30 }
+                else if c >= 'a' && c <= 'f' { (c as u8) - (0x61 - 10) }
+                else if c >= 'A' && c <= 'F' { (c as u8) - (0x41 - 10) }
+                else { fail ~"bad hex character"; };
+
+            if i % 2 == 0 {
+                unsafe {
+                    vec::push(&mut vec, nibble << 4);
+                }
+            }
+            else {
+                vec[i/2] |= nibble;
+            }
+        }
+
+        vec
+    }
+}
+
+#[cfg(test)]
+mod tests {
+
+    #[test]
+    pub fn test() {
+
+        assert [05u8, 0xffu8, 0x00u8, 0x59u8].to_hex() == ~"05FF0059";
+
+        assert "00FFA9D1F5".from_hex() == ~[0, 0xff, 0xa9, 0xd1, 0xf5];
+
+        assert "00FFA9D1F5".from_hex().to_hex() == ~"00FFA9D1F5";
+    }
+
+
+}
\ No newline at end of file