added test script

test.sh

@@ -0,0 +1,50 @@
+#!/bin/bash
+# Tests `chacha20`
+# 
+# Usage: ./test.sh [debug|release]
+# The binary must have already been built (use `cargo build [--release]` first)
+
+mkdir -p test || exit -1
+cd test || exit -1
+
+PROG=../target/${1:-release}/chacha20
+
+if [[ ! -f $PROG ]]; then
+	echo "Couldn't find executable \"$PROG\""
+	exit -1
+else
+	echo "Testing executable \"$PROG\""
+	echo ""
+fi
+
+INPUT_SIZE=4096
+
+echo ">>> Generating random input ($INPUT_SIZE bytes)"
+dd if=/dev/urandom "bs=$INPUT_SIZE" count=1 | base64 > test.txt
+
+echo ">>> Generating key + IV"
+KEYS=$($PROG k)
+echo "$KEYS"
+
+echo ">>> Encrypting"
+time $PROG e $KEYS  < test.txt  > test.cc20    || exit 1
+echo ">>> Decrypting"
+time $PROG d $KEYS  < test.cc20 > test.out.txt || exit 2
+
+echo ">>> Comparing"
+echo "Input (SHA256 sum):	$(sha256sum test.txt)"
+echo "Encrypted (SHA256 sum):	$(sha256sum test.cc20)"
+echo "Output (SHA256 sum):	$(sha256sum test.out.txt)"
+
+echo "---"
+if cmp --silent -- test.txt test.out.txt; then
+	echo "Pass!"
+else
+	echo "Failed"
+	exit 3
+fi
+
+rm test.*
+
+cd ..
+rmdir test || exit -1