Replaced String parameters with &[u8]

src/main.rs

@@ -8,32 +8,32 @@ fn main() {
 fn test_sha() {
     assert_eq!(
         "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
-        sha::sha256("".to_string()),
+        sha::sha256("".to_string().as_bytes()),
         "Testing hash for \"\""
     );
     assert_eq!(
         "ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad",
-        sha::sha256("abc".to_string()),
+        sha::sha256("abc".to_string().as_bytes()),
         "Testing hash for \"abc\""
     );
     assert_eq!(
         "d7a8fbb307d7809469ca9abcb0082e4f8d5651e46d3cdb762d02d0bf37c9e592",
-        sha::sha256("The quick brown fox jumps over the lazy dog".to_string()),
+        sha::sha256("The quick brown fox jumps over the lazy dog".to_string().as_bytes()),
         "Testing hash for \"The quick brown fox jumps over the lazy dog\""
     );
     assert_eq!(
         "d14a028c2a3a2bc9476102bb288234c415a2b01f828ea62ac5b3e42f",
-        sha::sha224("".to_string()),
+        sha::sha224("".to_string().as_bytes()),
         "Testing hash for \"\""
     );
     assert_eq!(
         "23097d223405d8228642a477bda255b32aadbce4bda0b3f7e36c9da7",
-        sha::sha224("abc".to_string()),
+        sha::sha224("abc".to_string().as_bytes()),
         "Testing hash for \"abc\""
     );
     assert_eq!(
         "730e109bd7a8a32b1cb9d9a09aa2325d2430587ddbc0c38bad911525",
-        sha::sha224("The quick brown fox jumps over the lazy dog".to_string()),
+        sha::sha224("The quick brown fox jumps over the lazy dog".to_string().as_bytes()),
         "Testing hash for \"The quick brown fox jumps over the lazy dog\""
     );
 }

src/sha/mod.rs

@@ -29,13 +29,13 @@ fn ssig1(x: u32) -> u32 {
     return ret;
 }
 
-fn pad_message(msg: String) -> Vec<u32> {
+fn pad_message(msg: &[u8]) -> Vec<u32> {
     let l = (msg.len() as u64) << 3;
     let k = ((448u64.wrapping_sub((l + 8) % 512) % 512) >> 3) as usize;
 
     let mut result_u8 = Vec::with_capacity(msg.len() + 1 + k + std::mem::size_of::<u64>());
 
-    result_u8.extend(msg.as_bytes());
+    result_u8.extend(msg);
     result_u8.push(0x80);
     result_u8.resize(result_u8.len() + k, 0u8);
     result_u8.extend(&l.to_be_bytes());
@@ -54,7 +54,7 @@ fn pad_message(msg: String) -> Vec<u32> {
 }
 //////////// END HELPER FUNCTIONS /////////////
 
-pub fn sha224(message: String) -> String {
+pub fn sha224(message: &[u8]) -> String {
     // Set initial hash values
     let init_hash_value: [u32; 8] = [
         0xc1059ed8, 0x367cd507, 0x3070dd17, 0xf70e5939, 0xffc00b31, 0x68581511, 0x64f98fa7,
@@ -72,7 +72,7 @@ pub fn sha224(message: String) -> String {
         .join("");
 }
 
-pub fn sha256(message: String) -> String {
+pub fn sha256(message: &[u8]) -> String {
     // Set initial hash values
     let init_hash_value: [u32; 8] = [
         0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a, 0x510e527f, 0x9b05688c, 0x1f83d9ab,
@@ -89,7 +89,7 @@ pub fn sha256(message: String) -> String {
         .join("");
 }
 
-fn sha_u32_calculate(init_hash_value: [u32; 8], message: String) -> [u32; 8] {
+fn sha_u32_calculate(init_hash_value: [u32; 8], message: &[u8]) -> [u32; 8] {
     // Fill constants array with values
     const K: [u32; 64] = [
         0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, 0x923f82a4,
@@ -109,10 +109,12 @@ fn sha_u32_calculate(init_hash_value: [u32; 8], message: String) -> [u32; 8] {
     // Pad message as required
     let msg_vec: Vec<u32> = pad_message(message);
 
+    // Initial word vector
+    let mut w: Vec<u32> = Vec::with_capacity(64);
+
     // Process each chunk 64 Byte of message vector
     for chunk in msg_vec.chunks(64) {
-        // Initialize temp variables and the word vector
-        let mut w: Vec<u32> = Vec::with_capacity(64);
+        // Initialize temp variables
         let mut t1: u32;
         let mut t2: u32;
 
@@ -168,6 +170,8 @@ fn sha_u32_calculate(init_hash_value: [u32; 8], message: String) -> [u32; 8] {
         hash[5] = f.wrapping_add(hash[5]);
         hash[6] = g.wrapping_add(hash[6]);
         hash[7] = h.wrapping_add(hash[7]);
+
+        w.clear();
     } // End of chunk processing
 
     // After processing the entire message concatenate the result into the final variable