diff --git a/openpgp/gitprotect.sh b/openpgp/gitprotect.sh
index 3fde2c84f33929cc5c0c90e2ffb82c1d689bca4c..04ac4bf0a73bd954a4ff40994193da6ded183890 100755
--- a/openpgp/gitprotect.sh
+++ b/openpgp/gitprotect.sh
@@ -276,9 +276,20 @@ elif [[ $command = "encrypt" ]]; then
     # Encrypt every file from the decrypted sub-directory.
     while read filePath; do
         filename=$(basename "$filePath")
-        cat "$filePath" | gpg2 --trust-model always --batch --homedir "$gnupgHome" \
-            --armor "${recipients[@]}" --encrypt > "${filename}.gpg"
-    done < <(find "decrypted/" -maxdepth 1 -type f)
+        checksumFile="decrypted/.${filename}.sha256"
+
+        # If the checksum file exists, then verify it. This way we detect if
+        # decrypted file has been changed in any way since it has been
+        # decrypted. We should skip unchanged files.
+        if [[ -f $checksumFile ]] && sha256sum --quiet -c "$checksumFile" > /dev/null 2>&1; then
+            echo "INFO: File decrypted/$filename doesn't seem to have been changed. Skipping."
+        # The file was changed, so we need to encrypt new version of it.
+        else
+            cat "$filePath" | gpg2 --trust-model always --batch --homedir "$gnupgHome" \
+                --armor "${recipients[@]}" --encrypt > "${filename}.gpg"
+            sha256sum "decrypted/$filename" > "decrypted/.${filename}.sha256"
+        fi
+    done < <(find "decrypted/" -maxdepth 1 -type f ! -name '.*.sha256')
 elif [[ $command = "decrypt" ]]; then
     gitprotectConfigured || exit "$ERR_NOCONFIG"
 
@@ -288,11 +299,21 @@ elif [[ $command = "decrypt" ]]; then
     # Process each GnuPG-encrypted file.
     while read filePath; do
         filename=$(basename "$filePath" ".gpg")
-
-        # Remove the "decrypted" file if decryption had failed.
-        if ! gpg2 --quiet --decrypt "$filePath" > "decrypted/$filename"; then
+        checksumFile="decrypted/.${filename}.sha256"
+
+        # If the checksum file exists, and it does not match, the destination
+        # file has been modified, so refuse to overwrite it.
+        if [[ -f $checksumFile ]] && ! sha256sum --quiet -c "$checksumFile" > /dev/null 2>&1; then
+            echo "ERROR: Current decrypted file 'decrypted/$filename' seems to have been modified since it was last decrypted."
+        # Decrypt the file. If decryption has failed, we've ended-up with empty
+        # file we need to remove.
+        elif ! gpg2 --quiet --decrypt "$filePath" > "decrypted/$filename"; then
             echo "ERROR: Failed to decrypt file '$filePath'. No private key available." >&2
             rm "decrypted/$filename"
+        # Create a new checksum file for checking if file had been changed by
+        # user or not.
+        else
+            sha256sum "decrypted/$filename" > "decrypted/.${filename}.sha256"
         fi
     done < <(find . -maxdepth 1 -name '*.gpg')
 else