setup_payload: Add support for parsing setup payloads in python impl

.github/workflows/build.yaml

@@ -333,7 +333,7 @@ jobs:
                   scripts/run_in_build_env.sh 'virtualenv pyenv'
                   source pyenv/bin/activate
                   pip3 install -r src/setup_payload/python/requirements.txt
-                  python3 src/setup_payload/tests/run_python_setup_payload_gen_test.py out/chip-tool
+                  python3 src/setup_payload/tests/run_python_setup_payload_test.py out/chip-tool
 
     build_linux_python_lighting_device:
         name: Build on Linux (python lighting-app)

scripts/tools/bouffalolab/factory_qrcode.py

@@ -20,13 +20,13 @@
 
 try:
     import qrcode
-    from generate_setup_payload import CommissioningFlow, SetupPayload
+    from SetupPayload import CommissioningFlow, SetupPayload
 except ImportError:
     SDK_ROOT = os.path.dirname(os.path.dirname(os.path.dirname(os.path.dirname(os.path.realpath(__file__)))))
     sys.path.append(os.path.join(SDK_ROOT, "src/setup_payload/python"))
     try:
         import qrcode
-        from generate_setup_payload import CommissioningFlow, SetupPayload
+        from SetupPayload import CommissioningFlow, SetupPayload
     except ModuleNotFoundError or ImportError:
         no_onboarding_modules = True
     else:

scripts/tools/generate_esp32_chip_factory_bin.py

@@ -30,7 +30,7 @@
 sys.path.insert(0, os.path.join(CHIP_TOPDIR, 'scripts', 'tools', 'spake2p'))
 from spake2p import generate_verifier  # noqa: E402 isort:skip
 sys.path.insert(0, os.path.join(CHIP_TOPDIR, 'src', 'setup_payload', 'python'))
-from generate_setup_payload import CommissioningFlow, SetupPayload  # noqa: E402 isort:skip
+from SetupPayload import CommissioningFlow, SetupPayload  # noqa: E402 isort:skip
 
 if os.getenv('IDF_PATH'):
     sys.path.insert(0, os.path.join(os.getenv('IDF_PATH'),

scripts/tools/nrfconnect/generate_nrfconnect_chip_factory_data.py

@@ -32,13 +32,13 @@
 
 try:
     import qrcode
-    from generate_setup_payload import CommissioningFlow, SetupPayload
+    from SetupPayload import CommissioningFlow, SetupPayload
 except ImportError:
     SDK_ROOT = os.path.dirname(os.path.dirname(os.path.dirname(os.path.dirname(os.path.realpath(__file__)))))
     sys.path.append(os.path.join(SDK_ROOT, "src/setup_payload/python"))
     try:
         import qrcode
-        from generate_setup_payload import CommissioningFlow, SetupPayload
+        from SetupPayload import CommissioningFlow, SetupPayload
     except ModuleNotFoundError or ImportError:
         no_onboarding_modules = True
     else:

src/setup_payload/python/Base38.py

@@ -24,6 +24,7 @@
 RADIX = len(CODES)
 BASE38_CHARS_NEEDED_IN_CHUNK = [2, 4, 5]
 MAX_BYTES_IN_CHUNK = 3
+MAX_ENCODED_BYTES_IN_CHUNK = 5
 
 
 def encode(bytes):
@@ -47,3 +48,25 @@ def encode(bytes):
             base38_chars_needed -= 1
 
     return qrcode
+
+
+def decode(qrcode):
+    total_chars = len(qrcode)
+    decoded_bytes = bytearray()
+
+    for i in range(0, total_chars, MAX_ENCODED_BYTES_IN_CHUNK):
+        if (i + MAX_ENCODED_BYTES_IN_CHUNK) > total_chars:
+            chars_in_chunk = total_chars - i
+        else:
+            chars_in_chunk = MAX_ENCODED_BYTES_IN_CHUNK
+
+        value = 0
+        for j in range(i + chars_in_chunk - 1, i - 1, -1):
+            value = value * RADIX + CODES.index(qrcode[j])
+
+        bytes_in_chunk = BASE38_CHARS_NEEDED_IN_CHUNK.index(chars_in_chunk) + 1
+        for k in range(0, bytes_in_chunk):
+            decoded_bytes.append(value & 0xFF)
+            value = value >> 8
+
+    return decoded_bytes

src/setup_payload/python/README.md

@@ -1,19 +1,22 @@
-## Python tool to generate Matter onboarding codes
+## Python tool to generate and parse Matter onboarding codes
 
-Generates Manual Pairing Code and QR Code
+Generates and parses Manual Pairing Code and QR Code
 
 #### example usage:
 
+-   Parse
+
 ```
-./generate_setup_payload.py -h
-./generate_setup_payload.py -d 3840 -p 20202021 -cf 0 -dm 2 -vid 65521 -pid 32768
+./SetupPayload.py parse MT:U9VJ0OMV172PX813210
+./SetupPayload.py parse 34970112332
 ```
 
--   Output
+-   Generate
 
 ```
-Manualcode : 34970112332
-QRCode     : MT:Y.K9042C00KA0648G00
+./SetupPayload.py generate --help
+./SetupPayload.py generate -d 3840 -p 20202021
+./SetupPayload.py generate -d 3840 -p 20202021 --vendor-id 65521 --product-id 32768 -cf 0 -dm 2
 ```
 
 For more details please refer Matter Specification

src/setup_payload/python/SetupPayload.py

@@ -0,0 +1,220 @@
+#!/usr/bin/env python3
+#
+# Copyright (c) 2024 Project CHIP Authors
+# All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import enum
+
+import Base38
+import click
+from bitarray import bitarray
+from bitarray.util import int2ba, zeros
+from construct import BitsInteger, BitStruct, Enum
+from stdnum.verhoeff import calc_check_digit
+
+# Format for constructing manualcode
+manualcode_format = BitStruct(
+    'version' / BitsInteger(1),
+    'vid_pid_present' / BitsInteger(1),
+    'discriminator' / BitsInteger(4),
+    'pincode_lsb' / BitsInteger(14),
+    'pincode_msb' / BitsInteger(13),
+    'vid' / BitsInteger(16),
+    'pid' / BitsInteger(16),
+    'padding' / BitsInteger(7),  # this is intentional as BitStruct only takes 8-bit aligned data
+)
+
+# Format for constructing qrcode
+# qrcode bytes are packed as lsb....msb, hence the order is reversed
+qrcode_format = BitStruct(
+    'padding' / BitsInteger(4),
+    'pincode' / BitsInteger(27),
+    'discriminator' / BitsInteger(12),
+    'discovery' / BitsInteger(8),
+    'flow' / Enum(BitsInteger(2),
+                  Standard=0, UserIntent=1, Custom=2),
+    'pid' / BitsInteger(16),
+    'vid' / BitsInteger(16),
+    'version' / BitsInteger(3),
+)
+
+
+class CommissioningFlow(enum.IntEnum):
+    Standard = 0,
+    UserIntent = 1,
+    Custom = 2
+
+
+class SetupPayload:
+    def __init__(self, discriminator, pincode, rendezvous=4, flow=CommissioningFlow.Standard, vid=0, pid=0):
+        self.long_discriminator = discriminator
+        self.short_discriminator = discriminator >> 8
+        self.pincode = pincode
+        self.discovery = rendezvous
+        self.flow = flow
+        self.vid = vid
+        self.pid = pid
+
+    def p_print(self):
+        print('{:<{}} :{}'.format('Flow', 24, self.flow))
+        print('{:<{}} :{}'.format('Pincode', 24, self.pincode))
+        print('{:<{}} :{}'.format('Short Discriminator', 24, self.short_discriminator))
+        if self.long_discriminator:
+            print('{:<{}} :{}'.format('Long Discriminator', 24, self.long_discriminator))
+        if self.discovery:
+            print('{:<{}} :{}'.format('Discovery Capabilities', 24, self.discovery))
+        if self.vid is not None and self.pid is not None:
+            print('{:<{}} :{:<{}} (0x{:04x})'.format('Vendor Id', 24, self.vid, 6, self.vid))
+            print('{:<{}} :{:<{}} (0x{:04x})'.format('Product Id', 24, self.pid, 6, self.pid))
+
+    def qrcode_dict(self):
+        return {
+            'version': 0,
+            'vid': self.vid,
+            'pid': self.pid,
+            'flow': int(self.flow),
+            'discovery': self.discovery,
+            'discriminator': self.long_discriminator,
+            'pincode': self.pincode,
+            'padding': 0,
+        }
+
+    def manualcode_dict(self):
+        return {
+            'version': 0,
+            'vid_pid_present': 0 if self.flow == CommissioningFlow.Standard else 1,
+            'discriminator': self.short_discriminator,
+            'pincode_lsb': self.pincode & 0x3FFF,    # 14 ls-bits
+            'pincode_msb': self.pincode >> 14,       # 13 ms-bits
+            'vid': 0 if self.flow == CommissioningFlow.Standard else self.vid,
+            'pid': 0 if self.flow == CommissioningFlow.Standard else self.pid,
+            'padding': 0,
+        }
+
+    def generate_qrcode(self):
+        data = qrcode_format.build(self.qrcode_dict())
+        b38_encoded = Base38.encode(data[::-1])  # reversing
+        return 'MT:{}'.format(b38_encoded)
+
+    def generate_manualcode(self):
+        CHUNK1_START = 0
+        CHUNK1_LEN = 4
+        CHUNK2_START = CHUNK1_START + CHUNK1_LEN
+        CHUNK2_LEN = 16
+        CHUNK3_START = CHUNK2_START + CHUNK2_LEN
+        CHUNK3_LEN = 13
+
+        bytes = manualcode_format.build(self.manualcode_dict())
+        bits = bitarray()
+        bits.frombytes(bytes)
+
+        chunk1 = str(int(bits[CHUNK1_START:CHUNK1_START + CHUNK1_LEN].to01(), 2)).zfill(1)
+        chunk2 = str(int(bits[CHUNK2_START:CHUNK2_START + CHUNK2_LEN].to01(), 2)).zfill(5)
+        chunk3 = str(int(bits[CHUNK3_START:CHUNK3_START + CHUNK3_LEN].to01(), 2)).zfill(4)
+        chunk4 = str(self.vid).zfill(5) if self.flow != CommissioningFlow.Standard else ''
+        chunk5 = str(self.pid).zfill(5) if self.flow != CommissioningFlow.Standard else ''
+        payload = '{}{}{}{}{}'.format(chunk1, chunk2, chunk3, chunk4, chunk5)
+        return '{}{}'.format(payload, calc_check_digit(payload))
+
+    @staticmethod
+    def from_container(container, is_qrcode):
+        payload = None
+        if is_qrcode:
+            payload = SetupPayload(container['discriminator'], container['pincode'],
+                                   container['discovery'], CommissioningFlow(container['flow'].__int__()),
+                                   container['vid'], container['pid'])
+        else:
+            payload = SetupPayload(discriminator=container['discriminator'],
+                                   pincode=(container['pincode_msb'] << 14) | container['pincode_lsb'],
+                                   vid=container['vid'] if container['vid_pid_present'] else None,
+                                   pid=container['pid'] if container['vid_pid_present'] else None)
+            payload.short_discriminator = container['discriminator']
+            payload.long_discriminator = None
+            payload.discovery = None
+            payload.flow = 2 if container['vid_pid_present'] else 0
+
+        return payload
+
+    @staticmethod
+    def parse_qrcode(payload):
+        payload = payload[3:]  # remove 'MT:'
+        b38_decoded = Base38.decode(payload)[::-1]
+        container = qrcode_format.parse(b38_decoded)
+        return SetupPayload.from_container(container, is_qrcode=True)
+
+    @staticmethod
+    def parse_manualcode(payload):
+        payload_len = len(payload)
+        if payload_len != 11 and payload_len != 21:
+            print('Invalid length')
+            return None
+
+        # if first digit is greater than 7 the its not v1
+        if int(str(payload)[0]) > 7:
+            print('incorrect first digit')
+            return None
+
+        if calc_check_digit(payload[:-1]) != str(payload)[-1]:
+            print('check digit mismatch')
+            return None
+
+        # vid_pid_present bit position
+        is_long = int(str(payload)[0]) & (1 << 2)
+
+        bits = int2ba(int(payload[0]), length=4)
+        bits += int2ba(int(payload[1:6]), length=16)
+        bits += int2ba(int(payload[6:10]), length=13)
+        bits += int2ba(int(payload[10:15]), length=16) if is_long else zeros(16)
+        bits += int2ba(int(payload[15:20]), length=16) if is_long else zeros(16)
+        bits += zeros(7)  # padding
+
+        container = manualcode_format.parse(bits.tobytes())
+        return SetupPayload.from_container(container, is_qrcode=False)
+
+    @staticmethod
+    def parse(payload):
+        if payload.startswith('MT:'):
+            return SetupPayload.parse_qrcode(payload)
+        else:
+            return SetupPayload.parse_manualcode(payload)
+
+
+@click.group()
+def cli():
+    pass
+
+
+@cli.command()
+@click.argument('payload')
+def parse(payload):
+    click.echo(f'Parsing payload: {payload}')
+    SetupPayload.parse(payload).p_print()
+
+
+@cli.command()
+@click.option('--discriminator', '-d', required=True, type=click.IntRange(0, 0xFFF), help='Discriminator')
+@click.option('--passcode', '-p', required=True, type=click.IntRange(1, 0x5F5E0FE), help='setup pincode')
+@click.option('--vendor-id', '-vid', type=click.IntRange(0, 0xFFFF), default=0, help='Vendor ID')
+@click.option('--product-id', '-pid', type=click.IntRange(0, 0xFFFF), default=0, help='Product ID')
+@click.option('--discovery-cap-bitmask', '-dm', type=click.IntRange(0, 7), default=4, help='Commissionable device discovery capability bitmask. 0:SoftAP, 1:BLE, 2:OnNetwork. Default: OnNetwork')
+@click.option('--commissioning-flow', '-cf', type=click.IntRange(0, 2), default=0, help='Commissioning flow, 0:Standard, 1:User-Intent, 2:Custom')
+def generate(passcode, discriminator, vendor_id, product_id, discovery_cap_bitmask, commissioning_flow):
+    payload = SetupPayload(discriminator, passcode, discovery_cap_bitmask, commissioning_flow, vendor_id, product_id)
+    print("Manualcode : {}".format(payload.generate_manualcode()))
+    print("QRCode     : {}".format(payload.generate_qrcode()))
+
+
+if __name__ == '__main__':
+    cli()