If client reception buffer is bigger than the first frame we receive, the first packet test
will always fail for the second one if it is shorter the the diffence between reception
buffer size and first frame length.
For example, if we receive a PUBLISH message with length = 1517 (payload len = 1514 +
header len = 3), this result in total message length of 1517.
altcp_tls will send MQTT client frame up to 1516 bytes max. This result to PUBLISH
message splitted in two frame: first is 1516 bytes, the second of 1 bytes.
If MQTT_VAR_HEADER_BUFFER_LEN is 1520 (1516 + 4 bytes for stored fixed header), the
second frame of 1 bytes is considered as first publish frame because
client->msg_idx (1517) < MQTT_VAR_HEADER_BUFFER_LEN (1520).
This result in disconnection AND application callback never called for the end of the
payload.
The fix will check `(client->msg_idx - (fixed_hdr_len + length)) == 0` which can be
only true for the first frame of a message.
Below logs showing the bug:
```
April 3rd 2019, 23:14:05.459 lwip_dbg mqtt_parse_incoming: Remaining length after fixed header: 1514
April 3rd 2019, 23:14:05.460 lwip_dbg mqtt_parse_incoming: msg_idx: 1516, cpy_len: 1513, remaining 1
April 3rd 2019, 23:14:05.460 lwip_dbg mqtt_incomming_publish: Received message with QoS 1 at topic: v2/inte...
April 3rd 2019, 23:14:05.461 lwip_dbg mqtt_parse_incoming: Remaining length after fixed header: 1514
April 3rd 2019, 23:14:05.461 lwip_dbg mqtt_parse_incoming: msg_idx: 1517, cpy_len: 1, remaining 0
April 3rd 2019, 23:14:05.461 lwip_dbg mqtt_message_received: Received short PUBLISH packet
```
- client->msg_idx can be > MQTT_VAR_HEADER_BUFFER_LEN in long message splitted in multiple pbufs
- renamed fixed_hdr_idx to fixed_hdr_len because it is length of fixed header in rx_buffer, not an index to it
- removed the cpy_start as data always copied right after the fixed header
See bug #54655:
"MQTT brokers such as Google Cloud IoT Core requires MQTT clients
to send JSON Web Token (JWT) as password field of the MQTT Connect
packet. JWT can be more than 255 bytes.
Currently, the MQTT library restricts password to be less than 256
bytes, thus it prevents connectivity to Google Cloud IoT Core."
Fix that by just converting the local variables for these from u8_t
to u16_t.
Suggested-by: Richmond Umagat <richmond.umagat@brtchip.com>
Signed-off-by: Simon Goldschmidt <goldsimon@gmx.de>
The boolean condition of setting the WILL flag differs from that of appending the will message
Found by Axel Lin
(I fixed it the same way as Axel suggested, but I wanted a different commit message)
This is a mqtt client, so it does not make sense to determinate the server port
at compile time. Update mqtt_client_connect() function to allow setting server
port.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
