„verify.sh“ hinzufügen

verify.sh

@@ -0,0 +1,26 @@
+#!/bin/bash
+# Verify a file with a public key using OpenSSL
+# Decode the signature from Base64 format
+#
+# Usage: verify <file> <signature> <public_key>
+#
+# NOTE: to generate a public/private key use the following commands:
+#
+# openssl genrsa -aes128 -passout pass:<passphrase> -out private.pem 2048
+# openssl rsa -in private.pem -passin pass:<passphrase> -pubout -out public.pem
+#
+# where <passphrase> is the passphrase to be used.
+
+filename=$1
+signature=$2
+publickey=$3
+tmpfile="$(mktemp)"
+
+if [[ $# -lt 3 ]] ; then
+  echo "Usage: verify <file> <signature> <public_key>"
+  exit 1
+fi
+
+openssl base64 -d -in $signature -out ${tmpfile}
+openssl dgst -sha256 -verify $publickey -signature ${tmpfile} $filename
+rm ${tmpfile}