Panic on Changing set_dst_pan_id Value in Packet Creation Example

[AmirAliEbrahimi]

Hello,

I encountered a panic when modifying the set_dst_pan_id value in the following packet creation example:

use dot15d4_frame::*;

fn main() {
    let frame = FrameBuilder::new_data(&[0x2b, 0x00, 0x00, 0x00])
        .set_sequence_number(1)
        .set_dst_pan_id(0xabcd)
        .set_dst_address(Address::Short([0x02, 0x04]))
        .set_src_pan_id(0xabcd)
        .set_src_address(Address::Extended([
            0x00, 0x12, 0x4b, 0x00, 0x14, 0xb5, 0xd9, 0xc7,
        ]))
        .finalize()
        .unwrap();

    let mut buffer = vec![0; frame.buffer_len()];

    frame.emit(&mut Frame::new_unchecked(&mut buffer[..]));

    println!("{:?}", frame);
    println!("packet = {:#04X?}", buffer);
}

This works fine and prints the packet as expected. However, if I change set_dst_pan_id to 0xabce, the program panics with the following error:

thread 'main' panicked at /home/aebrahimi/Projects/dot15d4/dot15d4-frame/src/lib.rs:469:40:
source slice length (4) does not match destination slice length (2)
stack backtrace:
   0: rust_begin_unwind
             at /builddir/build/BUILD/rust-1.83.0-build/rustc-1.83.0-src/library/std/src/panicking.rs:665:5
   1: core::panicking::panic_fmt
             at /builddir/build/BUILD/rust-1.83.0-build/rustc-1.83.0-src/library/core/src/panicking.rs:74:14
   2: core::slice::<impl [T]>::copy_from_slice::len_mismatch_fail
             at /builddir/build/BUILD/rust-1.83.0-build/rustc-1.83.0-src/library/core/src/slice/mod.rs:3685:13
   3: core::slice::<impl [T]>::copy_from_slice
             at /builddir/build/BUILD/rust-1.83.0-build/rustc-1.83.0-src/library/core/src/slice/mod.rs:3692:13
   4: dot15d4_frame::Frame<T>::set_payload
             at /home/aebrahimi/Projects/dot15d4/dot15d4-frame/src/lib.rs:469:9
   5: dot15d4_frame::repr::FrameRepr::emit
             at /home/aebrahimi/Projects/dot15d4/dot15d4-frame/src/repr/mod.rs:93:13
   6: test_app::main
             at ./src/main.rs:16:5
   7: core::ops::function::FnOnce::call_once
             at /builddir/build/BUILD/rust-1.83.0-build/rustc-1.83.0-src/library/core/src/ops/function.rs:250:5
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

Analysis:

Based on the error, it seems that the buffer length mismatch occurs because frame.buffer_len() reports the wrong size. This results in an incorrect buffer length during the emission, leading to the panic.

Could you please confirm if this is the expected behavior, or if there's something else causing the issue?

Thank you!

[thvdveld]

Thank you for filing an issue! The problem was that the builder omitted the source PAN ID. It is fixed in #30 .