fix(stack): grow CONNECT encode buffer to 1024 bytes#82
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The CONNECT packet is encoded into a 512-byte stack buffer. AWS IoT custom authentication passes the authorizer token as the MQTT password, which is a JWT several hundred bytes long; combined with client_id and username the encoded CONNECT exceeds 512 bytes and encode_packet fails, aborting the connection. Grow the buffer to 1024 to accommodate a full custom-auth CONNECT.
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Summary
The MQTT CONNECT packet is encoded into a 512-byte stack buffer (
src/stack.rs:566).AWS IoT custom authentication passes the authorizer token as the MQTT password, which is a JWT several hundred bytes long. Combined with
client_id,username, and anylast_will, the encoded CONNECT exceeds 512 bytes, soencode_packetfails and the connection is aborted before CONNACK.Grow the buffer to 1024 bytes to accommodate a full custom-auth CONNECT. The buffer is scoped to the CONNECT send and freed immediately after, so the extra stack is transient.