imgtool: Add raw output option

Signed-off-by: Dávid Házi <david.hazi@arm.com>
Signed-off-by: Bence Balogh <bence.balogh@arm.com>
Change-Id: Ia7f385e5e1b0471aae7693baa54e9a385ad3ae3f

scripts/imgtool/keys/general.py

@@ -41,6 +41,13 @@ class KeyClass(object):
                 len_format="const unsigned int {}_pub_key_len = {{}};".format(self.shortname()),
                 file=file)
 
+    def emit_raw_public(self, file=sys.stdout):
+        if file and file is not sys.stdout:
+            with open(file, 'wb') as file:
+                file.write(self.get_public_bytes())
+        else:
+            sys.stdout.buffer.write(self.get_public_bytes())
+
     def emit_rust_public(self, file=sys.stdout):
         self._emit(
                 header="static {}_PUB_KEY: &[u8] = &[".format(self.shortname().upper()),

scripts/imgtool/main.py

@@ -61,7 +61,7 @@ def gen_x25519(keyfile, passwd):
 
 
 valid_langs = ['c', 'rust']
-valid_encodings = ['lang-c', 'lang-rust', 'pem']
+valid_encodings = ['lang-c', 'lang-rust', 'pem', 'raw']
 keygens = {
     'rsa-2048':   gen_rsa2048,
     'rsa-3072':   gen_rsa3072,
@@ -152,6 +152,8 @@ def getpub(key, encoding, lang, output):
         key.emit_rust_public(file=output)
     elif encoding == 'pem':
         key.emit_public_pem(file=output)
+    elif encoding == 'raw':
+        key.emit_raw_public(file=output)
     else:
         raise click.UsageError()