binman: btool: Add fdt_add_pubkey as btool

Add btool which calls 'fdt_add_pubkey'

Signed-off-by: Lukas Funke <lukas.funke@weidmueller.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

tools/binman/btool/fdt_add_pubkey.py

@@ -0,0 +1,67 @@
+# SPDX-License-Identifier: GPL-2.0+
+# Copyright (C) 2023 Weidmüller Interface GmbH & Co. KG
+# Lukas Funke <lukas.funke@weidmueller.com>
+#
+"""Bintool implementation for fdt_add_pubkey"""
+
+from binman import bintool
+
+class Bintoolfdt_add_pubkey(bintool.Bintool):
+    """Add public key to control dtb (spl or u-boot proper)
+
+    This bintool supports running `fdt_add_pubkey`.
+
+    Normally mkimage adds signature information to the control dtb. However
+    binman images are built independent from each other. Thus it is required
+    to add the public key separately from mkimage.
+    """
+    def __init__(self, name):
+        super().__init__(name, 'Generate image for U-Boot')
+
+    # pylint: disable=R0913
+    def run(self, input_fname, keydir, keyname, required, algo):
+        """Run fdt_add_pubkey
+
+        Args:
+            input_fname (str): dtb file to sign
+            keydir (str): Directory with public key. Optional parameter,
+                default value: '.' (current directory)
+            keyname (str): Public key name. Optional parameter,
+                default value: key
+            required (str): If present this indicates that the key must be
+                verified for the image / configuration to be considered valid.
+            algo (str): Cryptographic algorithm. Optional parameter,
+                default value: sha1,rsa2048
+        """
+        args = []
+        if algo:
+            args += ['-a', algo]
+        if keydir:
+            args += ['-k', keydir]
+        if keyname:
+            args += ['-n', keyname]
+        if required:
+            args += ['-r', required]
+
+        args += [ input_fname ]
+
+        return self.run_cmd(*args)
+
+    def fetch(self, method):
+        """Fetch handler for fdt_add_pubkey
+
+        This installs fdt_add_pubkey using the apt utility.
+
+        Args:
+            method (FETCH_...): Method to use
+
+        Returns:
+            True if the file was fetched and now installed, None if a method
+            other than FETCH_BIN was requested
+
+        Raises:
+            Valuerror: Fetching could not be completed
+        """
+        if method != bintool.FETCH_BIN:
+            return None
+        return self.apt_install('u-boot-tools')