Public Access
twislaandClaude Opus 5.5
90cb6ef9b2
- scripts/ota_keygen.sh: ECDSA P-256 key pair; the private key goes to ~/.config/roro9stack/ (0600), the public key to keys/ and src/platform/ota_public_key.h; .gitignore refuses *key.pem - scripts/make_ota.py: wraps firmware.bin into a signed .ota (openssl) - scripts/ota_push.py: sends it over TCP 3232, prints the device's answer - scripts/flash.sh --ota <host>: build, sign, push Checked: a generated .ota has the documented layout and its signature verifies with openssl against the committed public key. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01EhqxQ49eCju4CzKYNjZzwT
51 lines
1.7 KiB
Python
Executable File
51 lines
1.7 KiB
Python
Executable File
#!/usr/bin/env python3
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"""Wraps a firmware image into a signed Update File (.ota). See lib/ota/src/update_parser.h.
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Usage: scripts/make_ota.py <firmware.bin> <version> <out.ota> [private key]
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Signs with openssl (ECDSA P-256 over SHA-256 of the header's first 80 bytes).
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"""
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import hashlib
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import os
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import struct
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import subprocess
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import sys
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import tempfile
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HEADER_SIZE = 160
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SIGNED_BYTES = 80
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MAX_SIGNATURE = 72
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def main():
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if len(sys.argv) < 4:
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sys.exit(__doc__)
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image_path, version, out_path = sys.argv[1:4]
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key = sys.argv[4] if len(sys.argv) > 4 else os.environ.get(
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"RORO_OTA_KEY", os.path.expanduser("~/.config/roro9stack/ota-key.pem"))
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if not os.path.exists(key):
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sys.exit(f"No signing key at {key}: run scripts/ota_keygen.sh first.")
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image = open(image_path, "rb").read()
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version_bytes = version.encode()[:31]
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signed = (b"RORO-OTA" + struct.pack("<HHI", 1, HEADER_SIZE, len(image)) +
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hashlib.sha256(image).digest() + version_bytes.ljust(32, b"\0"))
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assert len(signed) == SIGNED_BYTES
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with tempfile.NamedTemporaryFile() as f:
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f.write(signed)
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f.flush()
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signature = subprocess.run(["openssl", "dgst", "-sha256", "-sign", key, f.name],
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check=True, capture_output=True).stdout
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if len(signature) > MAX_SIGNATURE:
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sys.exit("unexpected signature size")
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header = signed + struct.pack("<H", len(signature)) + signature
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header = header.ljust(HEADER_SIZE, b"\0")
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with open(out_path, "wb") as out:
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out.write(header + image)
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print(f"{out_path}: {version}, {len(image)} bytes, signed")
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if __name__ == "__main__":
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main()
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