fix: CRC32 at a logical place

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Strix 2023-10-15 18:06:19 +02:00
parent 3f7c7f35bf
commit 7aee04e629
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GPG key ID: 49B2E37B8915B774

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@ -12,16 +12,16 @@ This can be changed with something like TLS but that's up to the implementer.
Packets are sent in big endian. Packets are sent in big endian.
| offset | size | name | description | example | | offset | size | name | description | example |
|--------|---------------------------|---------------|------------------------------------------------------------------------------------|--------------| |----------------------------------|---------------------------|---------------|------------------------------------------------------------------------------------|--------------|
| `0x00` | 1 byte | `version` | This describes the version of the packet | `0x01` | | `0x00` | 1 byte | `version` | This describes the version of the packet | `0x01` |
| `0x01` | 4 bytes | `src` | This describes who sent the packet a.k.a. source device id | `0xAABBCCDD` | | `0x01` | 4 bytes | `src` | This describes who sent the packet a.k.a. source device id | `0xAABBCCDD` |
| `0x05` | 4 bytes | `dest` | This describes who the packet is for a.k.a. destination device id | `0xAABBCCDD` | | `0x05` | 4 bytes | `dest` | This describes who the packet is for a.k.a. destination device id | `0xAABBCCDD` |
| `0x09` | 4 bytes | `checksum` | This is the CRC32 checksum of the *whole packet*. | `0x00000000` | | `0x09` | 4 bytes | `packet_id` | This is the unique identifier of the packet | `0xFAB1B39D` |
| `0x0D` | 4 bytes | `packet_id` | This is the unique identifier of the packet | `0xFAB1B39D` | | `0x0D` | 4 bytes | `reply_to` | This describes what this packet is replying to, if initial message, value is `0x0` | `0x00000000` |
| `0x11` | 4 bytes | `reply_to` | This describes what this packet is replying to, if initial message, value is `0x0` | `0x00000000` | | `0x11` | 1 byte | `command` | This describes what kind of command is sent | `0x00` |
| `0x12` | 1 byte | `command` | This describes what kind of command is sent | `0x00` | | `0x12` | 2 bytes | `data_length` | This describes the length of the data in bytes | `0x0001` |
| `0x13` | 2 bytes | `data_length` | This describes the length of the data in bytes | `0x0001` | | `0x14` | `<0x11-0x12:data_length>` | `data` | This is the data of the command | `0x00` |
| `0x15` | `<0x11-0x12:data_length>` | `data` | This is the data of the command | `0x00` | | `0x14 + <0x11-0x12:data_length>` | 4 bytes | `checksum` | This is the CRC32 checksum of the packet without the checksum. | `0x00000000` |
# Packets in practice # Packets in practice
@ -43,10 +43,10 @@ The "reserved" column (if present) will state what should be filled in by each s
# Error checking # Error checking
If the CRC32 doesn't match up the receiver will send a `0x0E` (error) packet to the probable source. If the CRC32 doesn't match up the receiver will send a `0x0E` (error) packet to the probable source.
The error code `0x01`/`net_broken_packet` should be used. The metadata may contain some textual info on what went wrong. The error code `0x01`/`net_broken_packet` should be used. The metadata may contain some textual info on what went
wrong.
The master will not track the broken packet's `packet_id`, so the slave can send it again. The master will not track the broken packet's `packet_id`, so the slave can send it again.
# Data types # Data types
Domo has a data framework reliant on data types. Domo has a data framework reliant on data types.
@ -92,7 +92,7 @@ This command will register a node.
| offset | size | name | description | example | | offset | size | name | description | example |
|--------|---------|-------------|------------------------------------------------|--------------| |--------|---------|-------------|------------------------------------------------|--------------|
| `0x15` | 4 bytes | `device_id` | the device identifier. (reserved for response) | `0x00000000` | | `0x14` | 4 bytes | `device_id` | the device identifier. (reserved for response) | `0x00000000` |
#### Example request #### Example request
@ -122,9 +122,9 @@ there is no extra data required.
| offset | size | name | description | reserved | example | | offset | size | name | description | reserved | example |
|--------|-----------|-----------------|---------------------------------------------|----------|---------| |--------|-----------|-----------------|---------------------------------------------|----------|---------|
| `0x15` | 32 bytes | `property_name` | The name of the property as a UTF-8 string. | no | "Power" | | `0x14` | 32 bytes | `property_name` | The name of the property as a UTF-8 string. | no | "Power" |
| `0x35` | 1 byte | `data_type` | The type of data; see "Data types". | no | `0x01` | | `0x34` | 1 byte | `data_type` | The type of data; see "Data types". | no | `0x01` |
| `0x36` | **1 bit** | `read_only` | Whether the property is readonly. | no | `0b0` | | `0x35` | **1 bit** | `read_only` | Whether the property is readonly. | no | `0b0` |
### `0x04` - Remove property ### `0x04` - Remove property
@ -132,7 +132,7 @@ there is no extra data required.
| offset | size | name | description | reserved | example | | offset | size | name | description | reserved | example |
|--------|----------|-----------------|---------------------------------------------|----------|---------| |--------|----------|-----------------|---------------------------------------------|----------|---------|
| `0x15` | 32 bytes | `property_name` | The name of the property as a UTF-8 string. | no | "Power" | | `0x14` | 32 bytes | `property_name` | The name of the property as a UTF-8 string. | no | "Power" |
### `0x0E` - Error ### `0x0E` - Error
@ -142,9 +142,9 @@ Send a packet to state an error occurred.
| offset | size | name | description | example | | offset | size | name | description | example |
|--------|-------------------------------|-------------------|---------------------------------|----------| |--------|-------------------------------|-------------------|---------------------------------|----------|
| `0x15` | 1 byte | `error_code` | error code; check 'Error codes' | `0x00` | | `0x14` | 1 byte | `error_code` | error code; check 'Error codes' | `0x00` |
| `0x16` | 2 bytes | `metadata_length` | metadata length | `0x0000` | | `0x15` | 2 bytes | `metadata_length` | metadata length | `0x0000` |
| `0x18` | `<0x14-0x15:metadata_length>` | `metadata` | metadata | | | `0x17` | `<0x14-0x15:metadata_length>` | `metadata` | metadata | |
#### Error codes #### Error codes
@ -168,9 +168,9 @@ Get a properties value
| offset | size | name | description | reserved | example | | offset | size | name | description | reserved | example |
|--------|-------------------------|-----------------|---------------------------------------------|----------|---------| |--------|-------------------------|-----------------|---------------------------------------------|----------|---------|
| `0x15` | 32 bytes | `property_name` | The name of the property as a UTF-8 string. | no | "Power" | | `0x14` | 32 bytes | `property_name` | The name of the property as a UTF-8 string. | no | "Power" |
| `0x35` | 1 byte | `data_type` | The type of the data. | response | `0x00` | | `0x34` | 1 byte | `data_type` | The type of the data. | response | `0x00` |
| `0x36` | determined by data type | `data` | The actual data. | response | | | `0x35` | determined by data type | `data` | The actual data. | response | |
### `0x11` - Set property ### `0x11` - Set property
@ -178,9 +178,9 @@ Get a properties value
| offset | size | name | description | reserved | example | | offset | size | name | description | reserved | example |
|--------|-------------------------|-----------------|---------------------------------------------|----------|---------| |--------|-------------------------|-----------------|---------------------------------------------|----------|---------|
| `0x15` | 32 bytes | `property_name` | The name of the property as a UTF-8 string. | no | "Power" | | `0x14` | 32 bytes | `property_name` | The name of the property as a UTF-8 string. | no | "Power" |
| `0x35` | 1 byte | `data_type` | The type of the data. | no | `0x00` | | `0x34` | 1 byte | `data_type` | The type of the data. | no | `0x00` |
| `0x36` | determined by data type | `data` | The actual data. | no | | | `0x35` | determined by data type | `data` | The actual data. | no | |
### `0x12` - Reset property ### `0x12` - Reset property
@ -188,4 +188,4 @@ Get a properties value
| offset | size | name | description | reserved | example | | offset | size | name | description | reserved | example |
|--------|----------|-----------------|---------------------------------------------|----------|---------| |--------|----------|-----------------|---------------------------------------------|----------|---------|
| `0x15` | 32 bytes | `property_name` | The name of the property as a UTF-8 string. | no | "Power" | | `0x14` | 32 bytes | `property_name` | The name of the property as a UTF-8 string. | no | "Power" |