mirror
/
MeshCore
mirror of https://github.com/meshcore-dev/MeshCore
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
Browse Source

fix: Align channel data framing 

ref: #1928
pull/1928/head
Janez T 3 months ago
parent
a21b83b127
commit
f25d7a882a
5 changed files with 63 additions and 56 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 42
      docs/companion_protocol.md
  2. 33
      examples/companion_radio/MyMesh.cpp
  3. 2
      src/MeshCore.h
  4. 2
      src/Packet.h
  5. 40
      src/helpers/BaseChatMesh.cpp

42
docs/companion_protocol.md
View File

@ -303,7 +303,7 @@ Bytes 7+: Binary payload bytes (variable length)
- Values other than `0xFF` are reserved for official protocol extensions.
**Limits**:
- Maximum payload length is `163` bytes (`MAX_GROUP_DATA_LENGTH`).
- Maximum payload length is `160` bytes.
- Larger payloads are rejected with `PACKET_ERROR` / `ERR_CODE_ILLEGAL_ARG`.
**Response**: `PACKET_OK` (0x00) on success
@ -326,7 +326,7 @@ Byte 0: 0x0A
**Response**:
- `PACKET_CHANNEL_MSG_RECV` (0x08) or `PACKET_CHANNEL_MSG_RECV_V3` (0x11) for channel messages
- `PACKET_CHANNEL_DATA_RECV` (0x1B) or `PACKET_CHANNEL_DATA_RECV_V3` (0x1C) for channel data
- `PACKET_CHANNEL_DATA_RECV` (0x1B) for channel data
- `PACKET_CONTACT_MSG_RECV` (0x07) or `PACKET_CONTACT_MSG_RECV_V3` (0x10) for contact messages
- `PACKET_NO_MORE_MSGS` (0x0A) if no messages available
@ -397,8 +397,7 @@ Messages are received via the TX characteristic (notifications). The device send
- `PACKET_CHANNEL_MSG_RECV_V3` (0x11) - Version 3 with SNR
2. **Channel Data**:
- `PACKET_CHANNEL_DATA_RECV` (0x1B) - Standard format
- `PACKET_CHANNEL_DATA_RECV_V3` (0x1C) - Version 3 with SNR
- `PACKET_CHANNEL_DATA_RECV` (0x1B) - Includes SNR and reserved bytes
3. **Contact Messages**:
- `PACKET_CONTACT_MSG_RECV` (0x07) - Standard format
@ -502,26 +501,17 @@ Bytes 11+: Payload bytes
### Channel Data Format
**Standard Format** (`PACKET_CHANNEL_DATA_RECV`, 0x1B):
**Format** (`PACKET_CHANNEL_DATA_RECV`, 0x1B):
```
Byte 0: 0x1B (packet type)
Byte 1: Channel Index (0-7)
Byte 2: Path Length
Byte 3: Data Type
Bytes 4-7: Timestamp (32-bit little-endian)
Bytes 8+: Payload bytes
```
**V3 Format** (`PACKET_CHANNEL_DATA_RECV_V3`, 0x1C):
```
Byte 0: 0x1C (packet type)
Byte 1: SNR (signed byte, multiplied by 4)
Bytes 2-3: Reserved
Byte 4: Channel Index (0-7)
Byte 5: Path Length
Byte 6: Data Type
Bytes 7-10: Timestamp (32-bit little-endian)
Bytes 11+: Payload bytes
Byte 7: Data Length
Bytes 8-11: Timestamp (32-bit little-endian)
Bytes 12+: Payload bytes
```
**Parsing Pseudocode**:
@ -529,9 +519,10 @@ Bytes 11+: Payload bytes
def parse_channel_frame(data):
packet_type = data[0]
offset = 1
snr = None
# Check for V3 format
if packet_type in (0x11, 0x1C): # V3
# Formats with explicit SNR/reserved bytes
if packet_type in (0x11, 0x1B):
snr_byte = data[offset]
snr = ((snr_byte if snr_byte < 128 else snr_byte - 256) / 4.0)
offset += 3 # Skip SNR + reserved
@ -539,8 +530,10 @@ def parse_channel_frame(data):
channel_idx = data[offset]
path_len = data[offset + 1]
item_type = data[offset + 2]
timestamp = int.from_bytes(data[offset+3:offset+7], 'little')
payload = data[offset+7:]
data_len = data[offset + 3] if packet_type == 0x1B else None
timestamp = int.from_bytes(data[offset+4:offset+8], 'little') if packet_type == 0x1B else int.from_bytes(data[offset+3:offset+7], 'little')
payload_offset = offset + 8 if packet_type == 0x1B else offset + 7
payload = data[payload_offset:payload_offset + data_len] if packet_type == 0x1B else data[payload_offset:]
is_text = packet_type in (0x08, 0x11)
if is_text and item_type == 0:
message = payload.decode('utf-8')
@ -553,7 +546,7 @@ def parse_channel_frame(data):
'timestamp': timestamp,
'payload': payload,
'message': message,
'snr': snr if packet_type in (0x11, 0x1C) else None
'snr': snr
}
```
@ -590,8 +583,7 @@ Use `CMD_SEND_CHANNEL_TXT_MSG` for plain text, and `CMD_SEND_CHANNEL_DATA` for b
| 0x10 | PACKET_CONTACT_MSG_RECV_V3 | Contact message (V3 with SNR) |
| 0x11 | PACKET_CHANNEL_MSG_RECV_V3 | Channel message (V3 with SNR) |
| 0x12 | PACKET_CHANNEL_INFO | Channel information |
| 0x1B | PACKET_CHANNEL_DATA_RECV | Channel data (standard) |
| 0x1C | PACKET_CHANNEL_DATA_RECV_V3| Channel data (V3 with SNR) |
| 0x1B | PACKET_CHANNEL_DATA_RECV | Channel data (includes SNR) |
| 0x80 | PACKET_ADVERTISEMENT | Advertisement packet |
| 0x82 | PACKET_ACK | Acknowledgment |
| 0x83 | PACKET_MESSAGES_WAITING | Messages waiting notification |
@ -892,7 +884,7 @@ def on_notification_received(data):
packet_type = data[0]
if packet_type in (PACKET_CHANNEL_MSG_RECV, PACKET_CHANNEL_MSG_RECV_V3,
PACKET_CHANNEL_DATA_RECV, PACKET_CHANNEL_DATA_RECV_V3):
PACKET_CHANNEL_DATA_RECV):
message = parse_channel_frame(data)
handle_channel_message(message)
elif packet_type == PACKET_MESSAGES_WAITING:

33
examples/companion_radio/MyMesh.cpp
View File

@ -93,7 +93,8 @@
#define RESP_CODE_AUTOADD_CONFIG 25
#define RESP_ALLOWED_REPEAT_FREQ 26
#define RESP_CODE_CHANNEL_DATA_RECV 27
#define RESP_CODE_CHANNEL_DATA_RECV_V3 28
#define MAX_CHANNEL_DATA_LENGTH (MAX_FRAME_SIZE - 12)
#define SEND_TIMEOUT_BASE_MILLIS 500
#define FLOOD_SEND_TIMEOUT_FACTOR 16.0f
@ -208,7 +209,7 @@ void MyMesh::updateContactFromFrame(ContactInfo &contact, uint32_t& last_mod, co
bool MyMesh::Frame::isChannelMsg() const {
return buf[0] == RESP_CODE_CHANNEL_MSG_RECV || buf[0] == RESP_CODE_CHANNEL_MSG_RECV_V3 ||
buf[0] == RESP_CODE_CHANNEL_DATA_RECV || buf[0] == RESP_CODE_CHANNEL_DATA_RECV_V3;
buf[0] == RESP_CODE_CHANNEL_DATA_RECV;
}
void MyMesh::addToOfflineQueue(const uint8_t frame[], int len) {
@ -570,28 +571,26 @@ void MyMesh::onChannelMessageRecv(const mesh::GroupChannel &channel, mesh::Packe
void MyMesh::onChannelDataRecv(const mesh::GroupChannel &channel, mesh::Packet *pkt, uint32_t timestamp, uint8_t data_type,
const uint8_t *data, size_t data_len) {
int i = 0;
if (app_target_ver >= 3) {
out_frame[i++] = RESP_CODE_CHANNEL_DATA_RECV_V3;
out_frame[i++] = (int8_t)(pkt->getSNR() * 4);
out_frame[i++] = 0; // reserved1
out_frame[i++] = 0; // reserved2
} else {
out_frame[i++] = RESP_CODE_CHANNEL_DATA_RECV;
if (data_len > MAX_CHANNEL_DATA_LENGTH) {
MESH_DEBUG_PRINTLN("onChannelDataRecv: dropping payload_len=%d exceeds frame limit=%d",
(uint32_t)data_len, (uint32_t)MAX_CHANNEL_DATA_LENGTH);
return;
}
int i = 0;
out_frame[i++] = RESP_CODE_CHANNEL_DATA_RECV;
out_frame[i++] = (int8_t)(pkt->getSNR() * 4);
out_frame[i++] = 0; // reserved1
out_frame[i++] = 0; // reserved2
uint8_t channel_idx = findChannelIdx(channel);
out_frame[i++] = channel_idx;
out_frame[i++] = pkt->isRouteFlood() ? pkt->path_len : 0xFF;
out_frame[i++] = data_type;
out_frame[i++] = (uint8_t)data_len;
memcpy(&out_frame[i], &timestamp, 4);
i += 4;
size_t available = MAX_FRAME_SIZE - i;
if (data_len > available) {
MESH_DEBUG_PRINTLN("onChannelDataRecv(): payload_len=%d exceeds frame space=%d, truncating", (uint32_t)data_len, (uint32_t)available);
data_len = available;
}
int copy_len = (int)data_len;
if (copy_len > 0) {
memcpy(&out_frame[i], data, copy_len);
@ -1108,8 +1107,8 @@ void MyMesh::handleCmdFrame(size_t len) {
writeErrFrame(ERR_CODE_NOT_FOUND); // bad channel_idx
} else if (data_type != DATA_TYPE_CUSTOM) {
writeErrFrame(ERR_CODE_UNSUPPORTED_CMD);
} else if (payload_len > MAX_GROUP_DATA_LENGTH) {
MESH_DEBUG_PRINTLN("CMD_SEND_CHANNEL_DATA payload too long: %d > %d", payload_len, MAX_GROUP_DATA_LENGTH);
} else if (payload_len > MAX_CHANNEL_DATA_LENGTH) {
MESH_DEBUG_PRINTLN("CMD_SEND_CHANNEL_DATA payload too long: %d > %d", payload_len, MAX_CHANNEL_DATA_LENGTH);
writeErrFrame(ERR_CODE_ILLEGAL_ARG);
} else if (sendGroupData(msg_timestamp, channel.channel, data_type, payload, payload_len)) {
writeOKFrame();

2
src/MeshCore.h
View File

@ -17,7 +17,7 @@
#define PATH_HASH_SIZE 1
#define MAX_PACKET_PAYLOAD 184
#define MAX_GROUP_DATA_LENGTH (MAX_PACKET_PAYLOAD - CIPHER_BLOCK_SIZE - 5)
#define MAX_GROUP_DATA_LENGTH (MAX_PACKET_PAYLOAD - CIPHER_BLOCK_SIZE - 6)
#define MAX_PATH_SIZE 64
#define MAX_TRANS_UNIT 255

2
src/Packet.h
View File

@ -22,7 +22,7 @@ namespace mesh {
#define PAYLOAD_TYPE_ACK 0x03 // a simple ack
#define PAYLOAD_TYPE_ADVERT 0x04 // a node advertising its Identity
#define PAYLOAD_TYPE_GRP_TXT 0x05 // an (unverified) group text message (prefixed with channel hash, MAC) (enc data: timestamp, "name: msg")
#define PAYLOAD_TYPE_GRP_DATA 0x06 // an (unverified) group datagram (prefixed with channel hash, MAC) (enc data: timestamp, blob)
#define PAYLOAD_TYPE_GRP_DATA 0x06 // an (unverified) group datagram (prefixed with channel hash, MAC) (enc data: timestamp, data_type, data_len, blob)
#define PAYLOAD_TYPE_ANON_REQ 0x07 // generic request (prefixed with dest_hash, ephemeral pub_key, MAC) (enc data: ...)
#define PAYLOAD_TYPE_PATH 0x08 // returned path (prefixed with dest/src hashes, MAC) (enc data: path, extra)
#define PAYLOAD_TYPE_TRACE 0x09 // trace a path, collecting SNI for each hop

40
src/helpers/BaseChatMesh.cpp
View File

@ -353,15 +353,15 @@ int BaseChatMesh::searchChannelsByHash(const uint8_t* hash, mesh::GroupChannel d
#endif
void BaseChatMesh::onGroupDataRecv(mesh::Packet* packet, uint8_t type, const mesh::GroupChannel& channel, uint8_t* data, size_t len) {
if (len < 5) {
MESH_DEBUG_PRINTLN("onGroupDataRecv: dropping short group payload len=%d", (uint32_t)len);
return;
}
uint8_t data_type = data[4];
if (type == PAYLOAD_TYPE_GRP_TXT) {
if ((data_type >> 2) != 0) {
MESH_DEBUG_PRINTLN("onGroupDataRecv: dropping unsupported group text type=%d", (uint32_t)data_type);
if (len < 5) {
MESH_DEBUG_PRINTLN("onGroupDataRecv: dropping short group text payload len=%d", (uint32_t)len);
return;
}
uint8_t txt_type = data[4];
if ((txt_type >> 2) != 0) {
MESH_DEBUG_PRINTLN("onGroupDataRecv: dropping unsupported group text type=%d", (uint32_t)txt_type);
return;
}
@ -374,9 +374,24 @@ void BaseChatMesh::onGroupDataRecv(mesh::Packet* packet, uint8_t type, const mes
// notify UI of this new message
onChannelMessageRecv(channel, packet, timestamp, (const char *) &data[5]); // let UI know
} else if (type == PAYLOAD_TYPE_GRP_DATA) {
if (len < 6) {
MESH_DEBUG_PRINTLN("onGroupDataRecv: dropping short group data payload len=%d", (uint32_t)len);
return;
}
uint32_t timestamp;
memcpy(&timestamp, data, 4);
onChannelDataRecv(channel, packet, timestamp, data_type, &data[5], len - 5);
uint8_t data_type = data[4];
uint8_t data_len = data[5];
size_t available_len = len - 6;
if (data_len > available_len) {
MESH_DEBUG_PRINTLN("onGroupDataRecv: dropping malformed group data type=%d len=%d available=%d",
(uint32_t)data_type, (uint32_t)data_len, (uint32_t)available_len);
return;
}
onChannelDataRecv(channel, packet, timestamp, data_type, &data[6], data_len);
}
}
@ -478,12 +493,13 @@ bool BaseChatMesh::sendGroupData(uint32_t timestamp, mesh::GroupChannel& channel
return false;
}
uint8_t temp[5 + MAX_GROUP_DATA_LENGTH];
uint8_t temp[6 + MAX_GROUP_DATA_LENGTH];
memcpy(temp, &timestamp, 4);
temp[4] = data_type;
if (data_len > 0) memcpy(&temp[5], data, data_len);
temp[5] = (uint8_t)data_len;
if (data_len > 0) memcpy(&temp[6], data, data_len);
auto pkt = createGroupDatagram(PAYLOAD_TYPE_GRP_DATA, channel, temp, 5 + data_len);
auto pkt = createGroupDatagram(PAYLOAD_TYPE_GRP_DATA, channel, temp, 6 + data_len);
if (pkt == NULL) {
MESH_DEBUG_PRINTLN("sendGroupData: unable to create group datagram, data_len=%d", data_len);
return false;

Write Preview
Loading…
Cancel
Save