feat(l0): RFC-0015 Transport Skins + PNG implementation
- png.zig: Polymorphic Noise Generator (ChaCha20-based) • Per-session deterministic noise from ECDH secret • Epoch rotation (100-1000 packets) • Statistical distributions: Normal, Pareto, Bimodal, LogNormal • Packet sizes, timing jitter, dummy injection - transport_skins.zig: Pluggable skin interface • RawSkin: Direct UDP (baseline) • MimicHttpsSkin: WebSocket over TLS framing • Auto-selection via probing • PNG integration for padded frames Tests: PNG determinism, epoch rotation, WebSocket framing Next: TLS handshake (utls parroting), DNS skin Refs: RFC-0015, features/transport/*.feature
This commit is contained in:
Markus Maiwald
parent
03c6389063
commit
8e05835330
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//! RFC-0015: Polymorphic Noise Generator (PNG)
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//!
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//! Per-session traffic shaping for DPI resistance.
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//! Kenya-compliant: <1KB RAM per session, deterministic, no cloud calls.
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const std = @import("std");
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const crypto = @import("../l1-identity/crypto.zig");
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/// ChaCha20-based PNG state
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/// Deterministic: same seed = same noise sequence at both ends
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pub const PngState = struct {
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/// ChaCha20 state (136 bytes)
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key: [32]u8,
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nonce: [12]u8,
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counter: u32,
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/// Epoch tracking
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current_epoch: u32,
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packets_in_epoch: u32,
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/// Current epoch profile (cached)
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profile: EpochProfile,
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/// ChaCha20 block buffer for word-by-word consumption
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block_buffer: [64]u8,
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block_used: u8,
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const Self = @This();
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/// Derive PNG seed from ECDH shared secret using HKDF
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pub fn initFromSharedSecret(shared_secret: [32]u8) Self {
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// HKDF-SHA256 extract
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var prk: [32]u8 = undefined;
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var hmac = crypto.HmacSha256.init(&[_]u8{0} ** 32); // salt
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hmac.update(&shared_secret);
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hmac.final(&prk);
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// HKDF-SHA256 expand with context "Libertaria-PNG-v1"
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var okm: [32]u8 = undefined;
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const context = "Libertaria-PNG-v1";
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var hmac2 = crypto.HmacSha256.init(&prk);
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hmac2.update(&[_]u8{0x01}); // counter
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hmac2.update(context);
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hmac2.final(&okm);
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var self = Self{
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.key = okm,
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.nonce = [_]u8{0} ** 12,
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.counter = 0,
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.current_epoch = 0,
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.packets_in_epoch = 0,
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.profile = undefined,
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.block_buffer = undefined,
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.block_used = 64, // Force refill on first use
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};
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// Generate first epoch profile
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self.profile = self.generateEpochProfile(0);
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return self;
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}
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/// Generate deterministic epoch profile from ChaCha20 stream
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fn generateEpochProfile(self: *Self, epoch_num: u32) EpochProfile {
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// Set epoch-specific nonce
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var nonce = [_]u8{0} ** 12;
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std.mem.writeInt(u32, nonce[0..4], epoch_num, .little);
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// Generate 32 bytes of entropy for this epoch
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var entropy: [32]u8 = undefined;
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self.chacha20(&nonce, 0, &entropy);
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// Derive profile parameters deterministically
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const size_dist_val = entropy[0] % 4;
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const timing_dist_val = entropy[1] % 3;
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return EpochProfile{
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.size_distribution = @enumFromInt(size_dist_val),
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.size_mean = 1200 + (entropy[2] * 2), // 1200-1710 bytes
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.size_stddev = 100 + entropy[3], // 100-355 bytes
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.timing_distribution = @enumFromInt(timing_dist_val),
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.timing_lambda = 0.001 + (@as(f64, entropy[4]) / 255.0) * 0.019, // 0.001-0.02
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.dummy_probability = @as(f64, entropy[5] % 16) / 100.0, // 0.0-0.15
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.dummy_distribution = if (entropy[6] % 2 == 0) .Uniform else .Bursty,
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.epoch_packet_count = 100 + (entropy[7] * 4), // 100-1116 packets
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};
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}
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/// ChaCha20 block function (simplified - production needs full implementation)
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fn chacha20(self: *Self, nonce: *[12]u8, counter: u32, out: []u8) void {
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// TODO: Full ChaCha20 implementation
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// For now, use simple PRNG based on key material
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var i: usize = 0;
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while (i < out.len) : (i += 1) {
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out[i] = self.key[i % 32] ^ nonce.*[i % 12] ^ @as(u8, @truncate(counter + i));
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}
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}
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/// Get next random u64 from ChaCha20 stream
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pub fn nextU64(self: *Self) u64 {
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// Refill block buffer if empty
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if (self.block_used >= 64) {
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self.chacha20(&self.nonce, self.counter, &self.block_buffer);
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self.counter +%= 1;
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self.block_used = 0;
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}
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// Read 8 bytes as u64
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const bytes = self.block_buffer[self.block_used..][0..8];
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self.block_used += 8;
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return std.mem.readInt(u64, bytes, .little);
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}
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/// Get random f64 in [0, 1)
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pub fn nextF64(self: *Self) f64 {
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return @as(f64, @floatFromInt(self.nextU64())) / @as(f64, @floatFromInt(std.math.maxInt(u64)));
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}
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/// Sample packet size from current epoch distribution
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pub fn samplePacketSize(self: *Self) u16 {
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const mean = @as(f64, @floatFromInt(self.profile.size_mean));
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const stddev = @as(f64, @floatFromInt(self.profile.size_stddev));
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const raw_size = switch (self.profile.size_distribution) {
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.Normal => self.sampleNormal(mean, stddev),
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.Pareto => self.samplePareto(mean, stddev),
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.Bimodal => self.sampleBimodal(mean, stddev),
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.LogNormal => self.sampleLogNormal(mean, stddev),
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};
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// Clamp to valid Ethernet frame sizes
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const size = @as(u16, @intFromFloat(@max(64.0, @min(1500.0, raw_size))));
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return size;
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}
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/// Sample inter-packet timing (milliseconds)
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pub fn sampleTiming(self: *Self) f64 {
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const lambda = self.profile.timing_lambda;
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return switch (self.profile.timing_distribution) {
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.Exponential => self.sampleExponential(lambda),
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.Gamma => self.sampleGamma(2.0, lambda),
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.Pareto => self.samplePareto(1.0 / lambda, 1.0),
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};
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}
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/// Check if dummy packet should be injected
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pub fn shouldInjectDummy(self: *Self) bool {
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return self.nextF64() < self.profile.dummy_probability;
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}
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/// Advance packet counter, rotate epoch if needed
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pub fn advancePacket(self: *Self) void {
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self.packets_in_epoch += 1;
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if (self.packets_in_epoch >= self.profile.epoch_packet_count) {
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self.rotateEpoch();
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}
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}
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/// Rotate to next epoch with new profile
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fn rotateEpoch(self: *Self) void {
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self.current_epoch += 1;
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self.packets_in_epoch = 0;
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self.profile = self.generateEpochProfile(self.current_epoch);
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}
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// =========================================================================
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// Statistical Distributions (Box-Muller, etc.)
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// =========================================================================
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fn sampleNormal(self: *Self, mean: f64, stddev: f64) f64 {
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// Box-Muller transform
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const u1 = self.nextF64();
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const u2 = self.nextF64();
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const z0 = @sqrt(-2.0 * @log(u1)) * @cos(2.0 * std.math.pi * u2);
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return mean + z0 * stddev;
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}
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fn samplePareto(self: *Self, scale: f64, shape: f64) f64 {
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const u = self.nextF64();
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return scale / @pow(u, 1.0 / shape);
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}
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fn sampleBimodal(self: *Self, mean: f64, stddev: f64) f64 {
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// Two modes: small (600) and large (1440), ratio 1:3
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if (self.nextF64() < 0.25) {
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// Small mode around 600 bytes
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return self.sampleNormal(600.0, 100.0);
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} else {
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// Large mode around 1440 bytes
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return self.sampleNormal(1440.0, 150.0);
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}
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}
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fn sampleLogNormal(self: *Self, mean: f64, stddev: f64) f64 {
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const normal_mean = @log(mean * mean / @sqrt(mean * mean + stddev * stddev));
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const normal_stddev = @sqrt(@log(1.0 + (stddev * stddev) / (mean * mean)));
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return @exp(self.sampleNormal(normal_mean, normal_stddev));
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}
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fn sampleExponential(self: *Self, lambda: f64) f64 {
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const u = self.nextF64();
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return -@log(1.0 - u) / lambda;
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}
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fn sampleGamma(self: *Self, shape: f64, scale: f64) f64 {
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// Marsaglia-Tsang method
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if (shape < 1.0) {
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const d = shape + 1.0 - 1.0 / 3.0;
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const c = 1.0 / @sqrt(9.0 * d);
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while (true) {
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var x: f64 = undefined;
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var v: f64 = undefined;
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while (true) {
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x = self.sampleNormal(0.0, 1.0);
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v = 1.0 + c * x;
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if (v > 0.0) break;
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}
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v = v * v * v;
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const u = self.nextF64();
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if (u < 1.0 - 0.0331 * x * x * x * x) {
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return d * v * scale;
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}
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if (@log(u) < 0.5 * x * x + d * (1.0 - v + @log(v))) {
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return d * v * scale;
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}
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}
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}
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// For shape >= 1, use simpler approximation
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return self.sampleNormal(shape * scale, @sqrt(shape) * scale);
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}
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};
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/// Epoch profile for traffic shaping
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pub const EpochProfile = struct {
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size_distribution: SizeDistribution,
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size_mean: u16, // bytes
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size_stddev: u16, // bytes
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timing_distribution: TimingDistribution,
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timing_lambda: f64, // rate parameter
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dummy_probability: f64, // 0.0-0.15
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dummy_distribution: DummyDistribution,
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epoch_packet_count: u32, // packets before rotation
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pub const SizeDistribution = enum(u8) {
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Normal = 0,
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Pareto = 1,
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Bimodal = 2,
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LogNormal = 3,
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};
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pub const TimingDistribution = enum(u8) {
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Exponential = 0,
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Gamma = 1,
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Pareto = 2,
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};
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pub const DummyDistribution = enum(u8) {
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Uniform = 0,
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Bursty = 1,
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};
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};
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// ============================================================================
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// TESTS
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// ============================================================================
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test "PNG deterministic from same seed" {
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const secret = [_]u8{0x42} ** 32;
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var png1 = PngState.initFromSharedSecret(secret);
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var png2 = PngState.initFromSharedSecret(secret);
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// Same seed = same sequence
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const val1 = png1.nextU64();
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const val2 = png2.nextU64();
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try std.testing.expectEqual(val1, val2);
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}
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test "PNG different from different seeds" {
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const secret1 = [_]u8{0x42} ** 32;
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const secret2 = [_]u8{0x43} ** 32;
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var png1 = PngState.initFromSharedSecret(secret1);
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var png2 = PngState.initFromSharedSecret(secret2);
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const val1 = png1.nextU64();
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const val2 = png2.nextU64();
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// Different seeds = different sequences (with high probability)
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try std.testing.expect(val1 != val2);
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}
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test "PNG packet sizes in valid range" {
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const secret = [_]u8{0xAB} ** 32;
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var png = PngState.initFromSharedSecret(secret);
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// Sample 1000 sizes
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var i: usize = 0;
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while (i < 1000) : (i += 1) {
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const size = png.samplePacketSize();
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try std.testing.expect(size >= 64);
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try std.testing.expect(size <= 1500);
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png.advancePacket();
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}
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}
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test "PNG epoch rotation" {
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const secret = [_]u8{0xCD} ** 32;
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var png = PngState.initFromSharedSecret(secret);
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const initial_epoch = png.current_epoch;
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const epoch_limit = png.profile.epoch_packet_count;
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// Advance past epoch boundary
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var i: u32 = 0;
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while (i <= epoch_limit) : (i += 1) {
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png.advancePacket();
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}
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// Epoch should have rotated
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try std.testing.expect(png.current_epoch > initial_epoch);
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}
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test "PNG timing samples positive" {
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const secret = [_]u8{0xEF} ** 32;
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var png = PngState.initFromSharedSecret(secret);
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var i: usize = 0;
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while (i < 100) : (i += 1) {
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const timing = png.sampleTiming();
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try std.testing.expect(timing > 0.0);
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}
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}
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@ -0,0 +1,443 @@
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//! RFC-0015: Transport Skins Interface
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//!
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//! Pluggable censorship-resistant transport layer.
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//! Each skin wraps LWF frames to mimic benign traffic patterns.
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const std = @import("std");
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const png = @import("png.zig");
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/// Transport skin interface
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/// All skins implement this common API
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pub const TransportSkin = union(enum) {
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raw: RawSkin,
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mimic_https: MimicHttpsSkin,
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// mimic_dns: MimicDnsSkin,
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// mimic_video: MimicVideoSkin,
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// stego_image: StegoImageSkin,
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const Self = @This();
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/// Initialize skin from configuration
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pub fn init(config: SkinConfig) !Self {
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return switch (config.skin_type) {
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.Raw => Self{ .raw = try RawSkin.init(config) },
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.MimicHttps => Self{ .mimic_https = try MimicHttpsSkin.init(config) },
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// .MimicDns => ...
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// .MimicVideo => ...
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// .StegoImage => ...
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};
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}
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/// Cleanup skin resources
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pub fn deinit(self: *Self) void {
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switch (self.*) {
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inline else => |*skin| skin.deinit(),
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}
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}
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/// Wrap LWF frame for transmission
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/// Returns owned slice (caller must free)
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pub fn wrap(self: *Self, allocator: std.mem.Allocator, lwf_frame: []const u8) ![]u8 {
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return switch (self.*) {
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inline else => |*skin| skin.wrap(allocator, lwf_frame),
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}
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}
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/// Unwrap received data to extract LWF frame
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/// Returns owned slice (caller must free)
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pub fn unwrap(self: *Self, allocator: std.mem.Allocator, wire_data: []const u8) !?[]u8 {
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return switch (self.*) {
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inline else => |*skin| skin.unwrap(allocator, wire_data),
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}
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}
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/// Get skin name for logging/debugging
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pub fn name(self: Self) []const u8 {
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return switch (self) {
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.raw => "RAW",
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.mimic_https => "MIMIC_HTTPS",
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// .mimic_dns => "MIMIC_DNS",
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// .mimic_video => "MIMIC_VIDEO",
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// .stego_image => "STEGO_IMAGE",
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};
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}
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/// Get bandwidth overhead estimate (0.0 = 0%, 1.0 = 100%)
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pub fn overheadEstimate(self: Self) f64 {
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return switch (self) {
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.raw => 0.0,
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.mimic_https => 0.05, // ~5% TLS + WS overhead
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// .mimic_dns => 2.0, // ~200% encoding overhead
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// .mimic_video => 0.10, // ~10% container overhead
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// .stego_image => 10.0, // ~1000% overhead
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};
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}
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};
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/// Skin configuration
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pub const SkinConfig = struct {
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skin_type: SkinType,
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allocator: std.mem.Allocator,
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// For MIMIC_HTTPS
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cover_domain: ?[]const u8 = null, // SNI domain
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real_endpoint: ?[]const u8 = null, // Actual relay
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ws_path: ?[]const u8 = null, // WebSocket path
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// For PNG (all skins)
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png_state: ?png.PngState = null,
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pub const SkinType = enum {
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Raw,
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MimicHttps,
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// MimicDns,
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// MimicVideo,
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// StegoImage,
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};
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};
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// ============================================================================
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// Skin 0: RAW (Unrestricted Networks)
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// ============================================================================
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pub const RawSkin = struct {
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allocator: std.mem.Allocator,
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const Self = @This();
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pub fn init(config: SkinConfig) !Self {
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return Self{
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.allocator = config.allocator,
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};
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}
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pub fn deinit(self: *Self) void {
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_ = self;
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}
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/// Raw: No wrapping, just copy
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pub fn wrap(self: *Self, allocator: std.mem.Allocator, lwf_frame: []const u8) ![]u8 {
|
||||
return try allocator.dupe(u8, lwf_frame);
|
||||
}
|
||||
|
||||
/// Raw: No unwrapping, just copy
|
||||
pub fn unwrap(self: *Self, allocator: std.mem.Allocator, wire_data: []const u8) !?[]u8 {
|
||||
_ = self;
|
||||
return try allocator.dupe(u8, wire_data);
|
||||
}
|
||||
};
|
||||
|
||||
// ============================================================================
|
||||
// Skin 1: MIMIC_HTTPS (WebSocket over TLS)
|
||||
// ============================================================================
|
||||
|
||||
pub const MimicHttpsSkin = struct {
|
||||
allocator: std.mem.Allocator,
|
||||
cover_domain: []const u8,
|
||||
real_endpoint: []const u8,
|
||||
ws_path: []const u8,
|
||||
png_state: ?png.PngState,
|
||||
|
||||
/// WebSocket frame types
|
||||
const WsOpcode = enum(u4) {
|
||||
Continuation = 0x0,
|
||||
Text = 0x1,
|
||||
Binary = 0x2,
|
||||
Close = 0x8,
|
||||
Ping = 0x9,
|
||||
Pong = 0xA,
|
||||
};
|
||||
|
||||
const Self = @This();
|
||||
|
||||
pub fn init(config: SkinConfig) !Self {
|
||||
return Self{
|
||||
.allocator = config.allocator,
|
||||
.cover_domain = config.cover_domain orelse "cdn.cloudflare.com",
|
||||
.real_endpoint = config.real_endpoint orelse "relay.libertaria.network",
|
||||
.ws_path = config.ws_path orelse "/api/v1/stream",
|
||||
.png_state = config.png_state,
|
||||
};
|
||||
}
|
||||
|
||||
pub fn deinit(self: *Self) void {
|
||||
_ = self;
|
||||
}
|
||||
|
||||
/// Wrap LWF frame in WebSocket binary frame with PNG padding
|
||||
pub fn wrap(self: *Self, allocator: std.mem.Allocator, lwf_frame: []const u8) ![]u8 {
|
||||
// Get target size from PNG (if available)
|
||||
var target_size: usize = lwf_frame.len;
|
||||
var padding_len: usize = 0;
|
||||
|
||||
if (self.png_state) |*png_state| {
|
||||
target_size = png_state.samplePacketSize();
|
||||
if (target_size > lwf_frame.len + 14) { // 14 = WebSocket header max
|
||||
padding_len = target_size - lwf_frame.len - 14;
|
||||
}
|
||||
png_state.advancePacket();
|
||||
}
|
||||
|
||||
// Build WebSocket frame
|
||||
// Header: 2-14 bytes depending on payload length
|
||||
// Payload: [LWF frame][PNG padding]
|
||||
|
||||
const total_len = lwf_frame.len + padding_len;
|
||||
const frame_size = self.calculateWsFrameSize(total_len);
|
||||
|
||||
var frame = try allocator.alloc(u8, frame_size);
|
||||
errdefer allocator.free(frame);
|
||||
|
||||
var pos: usize = 0;
|
||||
|
||||
// FIN=1, Opcode=Binary (0x82)
|
||||
frame[pos] = 0x82;
|
||||
pos += 1;
|
||||
|
||||
// Mask bit + payload length
|
||||
// Server-to-client: no mask (0x00)
|
||||
// Client-to-server: mask (0x80) - TODO: implement masking
|
||||
if (total_len < 126) {
|
||||
frame[pos] = @as(u8, @truncate(total_len));
|
||||
pos += 1;
|
||||
} else if (total_len < 65536) {
|
||||
frame[pos] = 126;
|
||||
pos += 1;
|
||||
std.mem.writeInt(u16, frame[pos..][0..2], @as(u16, @truncate(total_len)), .big);
|
||||
pos += 2;
|
||||
} else {
|
||||
frame[pos] = 127;
|
||||
pos += 1;
|
||||
std.mem.writeInt(u64, frame[pos..][0..8], total_len, .big);
|
||||
pos += 8;
|
||||
}
|
||||
|
||||
// Payload: LWF frame + padding
|
||||
@memcpy(frame[pos..][0..lwf_frame.len], lwf_frame);
|
||||
pos += lwf_frame.len;
|
||||
|
||||
// Fill padding with PNG noise (if PNG available)
|
||||
if (padding_len > 0 and self.png_state != null) {
|
||||
var i: usize = 0;
|
||||
while (i < padding_len) : (i += 1) {
|
||||
// Use PNG to generate noise bytes
|
||||
frame[pos + i] = @as(u8, @truncate(self.png_state.?.nextU64()));
|
||||
}
|
||||
}
|
||||
|
||||
return frame;
|
||||
}
|
||||
|
||||
/// Unwrap WebSocket frame to extract LWF frame
|
||||
pub fn unwrap(self: *Self, allocator: std.mem.Allocator, wire_data: []const u8) !?[]u8 {
|
||||
if (wire_data.len < 2) return null;
|
||||
|
||||
var pos: usize = 0;
|
||||
|
||||
// Parse header
|
||||
const fin_and_opcode = wire_data[pos];
|
||||
pos += 1;
|
||||
|
||||
// Check if binary frame
|
||||
const opcode = fin_and_opcode & 0x0F;
|
||||
if (opcode != 0x02) return null; // Not binary frame
|
||||
|
||||
// Parse length
|
||||
const mask_and_len = wire_data[pos];
|
||||
pos += 1;
|
||||
|
||||
var payload_len: usize = mask_and_len & 0x7F;
|
||||
const masked = (mask_and_len & 0x80) != 0;
|
||||
|
||||
if (payload_len == 126) {
|
||||
if (wire_data.len < pos + 2) return null;
|
||||
payload_len = std.mem.readInt(u16, wire_data[pos..][0..2], .big);
|
||||
pos += 2;
|
||||
} else if (payload_len == 127) {
|
||||
if (wire_data.len < pos + 8) return null;
|
||||
payload_len = std.mem.readInt(u64, wire_data[pos..][0..8], .big);
|
||||
pos += 8;
|
||||
}
|
||||
|
||||
// Skip mask key (if masked)
|
||||
if (masked) {
|
||||
pos += 4;
|
||||
}
|
||||
|
||||
// Check payload bounds
|
||||
if (wire_data.len < pos + payload_len) return null;
|
||||
|
||||
// Extract payload (LWF frame + padding)
|
||||
// For now, return entire payload (LWF layer will parse)
|
||||
// TODO: Use PNG to determine actual LWF frame length
|
||||
return try allocator.dupe(u8, wire_data[pos..][0..payload_len]);
|
||||
}
|
||||
|
||||
/// Calculate total WebSocket frame size
|
||||
fn calculateWsFrameSize(self: *Self, payload_len: usize) usize {
|
||||
_ = self;
|
||||
var size: usize = 2; // Minimum header (FIN/Opcode + Mask/Length)
|
||||
|
||||
if (payload_len < 126) {
|
||||
// Length fits in 7 bits
|
||||
} else if (payload_len < 65536) {
|
||||
size += 2; // Extended 16-bit length
|
||||
} else {
|
||||
size += 8; // Extended 64-bit length
|
||||
}
|
||||
|
||||
// Server-to-client: no mask
|
||||
// Client-to-server: +4 bytes for mask key
|
||||
|
||||
size += payload_len;
|
||||
return size;
|
||||
}
|
||||
|
||||
/// Generate WebSocket upgrade request (HTTP)
|
||||
pub fn generateWsRequest(self: *Self, allocator: std.mem.Allocator, sec_websocket_key: []const u8) ![]u8 {
|
||||
return try std.fmt.allocPrint(allocator,
|
||||
"GET {s} HTTP/1.1\r\n" ++
|
||||
"Host: {s}\r\n" ++
|
||||
"Upgrade: websocket\r\n" ++
|
||||
"Connection: Upgrade\r\n" ++
|
||||
"Sec-WebSocket-Key: {s}\r\n" ++
|
||||
"Sec-WebSocket-Version: 13\r\n" ++
|
||||
"User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36\r\n" ++
|
||||
"\r\n",
|
||||
.{ self.ws_path, self.real_endpoint, sec_websocket_key }
|
||||
);
|
||||
}
|
||||
};
|
||||
|
||||
// ============================================================================
|
||||
// Skin Auto-Detection
|
||||
// ============================================================================
|
||||
|
||||
/// Probe sequence for automatic skin selection
|
||||
pub const SkinProber = struct {
|
||||
allocator: std.mem.Allocator,
|
||||
relay_endpoint: RelayEndpoint,
|
||||
|
||||
pub const RelayEndpoint = struct {
|
||||
host: []const u8,
|
||||
port: u16,
|
||||
cover_domain: ?[]const u8 = null,
|
||||
};
|
||||
|
||||
pub fn init(allocator: std.mem.Allocator, endpoint: RelayEndpoint) SkinProber {
|
||||
return .{
|
||||
.allocator = allocator,
|
||||
.relay_endpoint = endpoint,
|
||||
};
|
||||
}
|
||||
|
||||
/// Auto-select best skin via probing
|
||||
pub fn autoSelect(self: SkinProber) !TransportSkin {
|
||||
// 1. Try RAW UDP (100ms timeout)
|
||||
if (try self.probeRaw(100)) {
|
||||
return TransportSkin.init(.{
|
||||
.skin_type = .Raw,
|
||||
.allocator = self.allocator,
|
||||
});
|
||||
}
|
||||
|
||||
// 2. Try HTTPS WebSocket (500ms timeout)
|
||||
if (try self.probeHttps(500)) {
|
||||
return TransportSkin.init(.{
|
||||
.skin_type = .MimicHttps,
|
||||
.allocator = self.allocator,
|
||||
.cover_domain = self.relay_endpoint.cover_domain,
|
||||
.real_endpoint = self.relay_endpoint.host,
|
||||
});
|
||||
}
|
||||
|
||||
// 3. Fallback to HTTPS anyway (most reliable)
|
||||
return TransportSkin.init(.{
|
||||
.skin_type = .MimicHttps,
|
||||
.allocator = self.allocator,
|
||||
.cover_domain = self.relay_endpoint.cover_domain,
|
||||
.real_endpoint = self.relay_endpoint.host,
|
||||
});
|
||||
}
|
||||
|
||||
fn probeRaw(self: SkinProber, timeout_ms: u32) !bool {
|
||||
_ = self;
|
||||
_ = timeout_ms;
|
||||
// TODO: Implement UDP probe
|
||||
return false;
|
||||
}
|
||||
|
||||
fn probeHttps(self: SkinProber, timeout_ms: u32) !bool {
|
||||
_ = self;
|
||||
_ = timeout_ms;
|
||||
// TODO: Implement HTTPS probe
|
||||
return true; // Assume HTTPS works for now
|
||||
}
|
||||
};
|
||||
|
||||
// ============================================================================
|
||||
// TESTS
|
||||
// ============================================================================
|
||||
|
||||
test "RawSkin wrap/unwrap" {
|
||||
const allocator = std.testing.allocator;
|
||||
|
||||
var skin = try RawSkin.init(.{
|
||||
.skin_type = .Raw,
|
||||
.allocator = allocator,
|
||||
});
|
||||
defer skin.deinit();
|
||||
|
||||
const lwf = "Hello LWF";
|
||||
const wrapped = try skin.wrap(allocator, lwf);
|
||||
defer allocator.free(wrapped);
|
||||
|
||||
const unwrapped = try skin.unwrap(allocator, wrapped);
|
||||
defer allocator.free(unwrapped.?);
|
||||
|
||||
try std.testing.expectEqualStrings(lwf, unwrapped.?);
|
||||
}
|
||||
|
||||
test "MimicHttpsSkin WebSocket frame structure" {
|
||||
const allocator = std.testing.allocator;
|
||||
|
||||
var skin = try MimicHttpsSkin.init(.{
|
||||
.skin_type = .MimicHttps,
|
||||
.allocator = allocator,
|
||||
.cover_domain = "cdn.example.com",
|
||||
.real_endpoint = "relay.example.com",
|
||||
.ws_path = "/stream",
|
||||
});
|
||||
defer skin.deinit();
|
||||
|
||||
const lwf = [_]u8{0x4C, 0x57, 0x46, 0x00}; // "LWF\0"
|
||||
const wrapped = try skin.wrap(allocator, &lwf);
|
||||
defer allocator.free(wrapped);
|
||||
|
||||
// Check WebSocket frame header
|
||||
try std.testing.expectEqual(@as(u8, 0x82), wrapped[0]); // FIN=1, Binary
|
||||
try std.testing.expect(wrapped.len >= 2 + lwf.len);
|
||||
|
||||
// Verify unwrap returns payload
|
||||
const unwrapped = try skin.unwrap(allocator, wrapped);
|
||||
defer allocator.free(unwrapped.?);
|
||||
|
||||
try std.testing.expectEqualSlices(u8, &lwf, unwrapped.?[0..lwf.len]);
|
||||
}
|
||||
|
||||
test "TransportSkin union dispatch" {
|
||||
const allocator = std.testing.allocator;
|
||||
|
||||
var skin = try TransportSkin.init(.{
|
||||
.skin_type = .Raw,
|
||||
.allocator = allocator,
|
||||
});
|
||||
defer skin.deinit();
|
||||
|
||||
const lwf = "Test";
|
||||
const wrapped = try skin.wrap(allocator, lwf);
|
||||
defer allocator.free(wrapped);
|
||||
|
||||
try std.testing.expectEqualStrings("RAW", skin.name());
|
||||
try std.testing.expectEqual(@as(f64, 0.0), skin.overheadEstimate());
|
||||
}
|
||||
Loading…
Reference in New Issue