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feat: implement asymmetric syn_udp transport and add multi-inbound su…
add web panel
set workflows for panel
chore: update Zig installation path to user home directory in CI work…
refactor: migrate to pure Go SQLite driver to enable static cross-com…
New Core architecture, v3.0.0
fix: ensure tester results exist and optimize rendering by memoizing …
feat: replace download link and apply action with a client-side file …
feat: add support for dynamic web path prefixing to all frontend rout…
Added a donation section to the README file.
back runner to ubuntu22
feat: add file path support for IP lists, implement tunnel auto-start and update version to 3.0.2
feat: add TCP destination port filtering support for receiver mode
…ceive ## Architecture Restructure Rust workspace into three crates: - spoof-transport: existing raw socket transport (moved from rust/src/) - xdp-ebpf: eBPF program compiled for bpfel-unknown-none target - xdp-loader: userspace loader using aya for XDP program management ## XDP eBPF Program (rust/xdp-ebpf/) - Parses Ethernet/IPv4 headers using fixed constant offsets (14+20) to satisfy the BPF verifier's strict bounds checking - Filters packets by protocol, peer spoof IP, and destination port via BPF HashMap config map - Uses bpf_xdp_load_bytes() kernel helper for payload copy into ring buffer, avoiding the verifier's variable-offset packet pointer access restrictions - Inline asm (asm_experimental_arch) to emit AND/OR instructions that the BPF verifier can track for argument bounds - Returns XDP_DROP for matched packets (zero-copy to userspace) - Returns XDP_PASS for non-matching traffic (normal stack) ## XDP Loader (rust/xdp-loader/) - Embeds compiled eBPF ELF at compile time via include_bytes!() - build.rs tracks eBPF binary for proper change detection - Aligned copy mechanism for ELF data (8-byte alignment required) - Configures BPF maps: CONFIG (filter params), PAYLOADS (ring buf), PKT_COUNT (statistics) - Ring buffer consumer thread delivers packets to Go via FFI - Graceful XDP detach on close ## Go Integration - New XDPReceiver type in internal/transport/xdp_receiver.go - Factory pattern: --xdp-interface flag triggers XDP-first with automatic fallback to raw socket on failure - CGo FFI via spoof_transport.h for XDP lifecycle management - Config support: xdp_interface field in JSON config ## Build System - xdp-ebpf excluded from Cargo workspace (separate nightly toolchain) - Makefile updated for two-phase Rust build (eBPF then workspace) - .gitignore updated for xdp-ebpf build artifacts ## Key BPF Verifier Solutions - Fixed header offsets (no variable IHL/doff) for packet access - bpf_xdp_load_bytes() instead of manual byte-copy loop - Inline asm for payload_len masking (LLVM optimizes away Rust masks) - Ring buffer entry sized to accommodate masked max (2064 bytes)
Add build-ebpf job to both test.yml and release.yml: - Uses nightly Rust toolchain with rust-src component - Compiles xdp-ebpf crate for bpfel-unknown-none target - Passes eBPF binary to downstream jobs via upload-artifact Update Rust build jobs: - Install libelf-dev (required by aya for ELF object parsing) - Download eBPF binary artifact before building Rust workspace - Use -p spoof-transport flag in test workflow for targeted build Job dependency graph: build-ebpf → test-rust build-ebpf → test-go (test.yml) build-ebpf → test-rust → build-tunnel (release.yml) The eBPF program is architecture-independent (bpfel-unknown-none) so it only needs to be built once and shared across amd64/arm64 jobs.
…ection
## Root cause: | 1 bug causing ~50% packet loss
The previous asm block used 'r0 |= 1' to ensure the verifier saw
min=1. This corrupted the actual value:
- payload_len=100 (even) → safe_len=101 → bpf_xdp_load_bytes
tried to read 101 bytes from a 100-byte payload → FAIL
- Failed entries were discarded → ~50% of packets dropped
- Surviving packets had length off-by-one → garbled data
## Fix: single asm block with inline conditional branch
Use a single asm block that:
1. Masks: r2 = payload_len & 0x7FF (verifier: [0, 2047])
2. Branch: if r2 == 0 goto skip (verifier narrowing)
3. Sets args and calls bpf_xdp_load_bytes#189 directly
4. On zero path: returns -1 to signal skip
The verifier can follow the conditional branch and knows that on
the fall-through path r2 (the length arg) is in [1, 2047].
This completely avoids the 'zero-sized read' verifier error.
The zero case never triggers at runtime since payload_len >= 1
is checked earlier, but the verifier needs the proof.
## Also removes unused import
bpf_xdp_load_bytes is now called via raw asm 'call 189' so
the aya_ebpf_bindings import is no longer needed.
The asm block was not setting r2 (offset argument) correctly. r2 contained the masked payload_len instead of payload_offset, causing bpf_xdp_load_bytes to read from the wrong location in the packet (e.g. offset 10 in IP header instead of offset 54 where TCP payload starts). This resulted in IP/TCP header bytes being returned as payload data, causing garbled output on the receiving end. Fix: add payload_offset as input register r8 and set r2 = r8 before the call. Also fix the goto offset from +5 to +6 since the call setup now uses 4 instructions instead of 3. Args to bpf_xdp_load_bytes (helper #189): r1 = xdp_md context r2 = offset in packet ← was wrong (payload_len), now correct r3 = destination buffer r4 = length to copy
When the TCP sender fragments packets (payload + TCP overhead > MTU), the XDP program was DROPping the first fragment (which has the TCP header) while PASSing subsequent fragments (no TCP header → bounds check fail). The kernel couldn't reassemble because the first fragment was missing, causing 0 throughput at higher WireGuard MTUs. Fix: check IP flags/fragment-offset field (bytes 6-7 of IP header). If MF (More Fragments) bit is set OR fragment offset > 0, return XDP_PASS to let the kernel handle reassembly via the raw socket receiver fallback. This restores correct behavior for WireGuard MTU 1280+ while keeping the XDP fast path for non-fragmented packets.
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