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-rw-r--r--scripts/signrom.py40
1 files changed, 40 insertions, 0 deletions
diff --git a/scripts/signrom.py b/scripts/signrom.py
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+++ b/scripts/signrom.py
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+#
+# Option ROM signing utility
+#
+# Authors:
+# Jan Kiszka <jan.kiszka@siemens.com>
+#
+# This work is licensed under the terms of the GNU GPL, version 2 or later.
+# See the COPYING file in the top-level directory.
+
+import sys
+import struct
+
+if len(sys.argv) < 3:
+ print('usage: signrom.py input output')
+ sys.exit(1)
+
+fin = open(sys.argv[1], 'rb')
+fout = open(sys.argv[2], 'wb')
+
+fin.seek(2)
+size = ord(fin.read(1)) * 512 - 1
+
+fin.seek(0)
+data = fin.read(size)
+fout.write(data)
+
+checksum = 0
+for b in data:
+ # catch Python 2 vs. 3 differences
+ if isinstance(b, int):
+ checksum += b
+ else:
+ checksum += ord(b)
+checksum = (256 - checksum) % 256
+
+# Python 3 no longer allows chr(checksum)
+fout.write(struct.pack('B', checksum))
+
+fin.close()
+fout.close()