feat(stun): Add stun types [rfc 8489]

README.md

@@ -7,3 +7,4 @@ The projects is structured into modules, each module is a separate library that
 * `rtp` - [RTP (Real-time Transport Protocol)](https://datatracker.ietf.org/doc/html/rfc3550) implementation for media streaming based on RFC 3550.
 * `sdp` - [SDP (Session Description Protocol)](https://datatracker.ietf.org/doc/html/rfc4566) implementation for describing multimedia sessions based on RFC 4566.
 * `rtsp` - [RTSP (Real Time Streaming Protocol)](https://datatracker.ietf.org/doc/html/rfc2326) implementation for controlling streaming media servers based on RFC 2326.
+* `stun` - [STUN (Session Traversal Utilities for NAT)](https://datatracker.ietf.org/doc/html/rfc8489) implementation for NAT traversal based on RFC 5389.

bench/stun/message.zig

@@ -0,0 +1,97 @@
+const std = @import("std");
+const zbench = @import("zbench");
+const stun = @import("stun");
+
+// Binding request, no attributes (header only)
+const empty_request = [_]u8{
+    0x00, 0x01, 0x00, 0x00,
+    0x21, 0x12, 0xA4, 0x42,
+    0x00, 0x01, 0x02, 0x03,
+    0x04, 0x05, 0x06, 0x07,
+    0x08, 0x09, 0x0A, 0x0B,
+};
+
+// Binding success response with MAPPED-ADDRESS (IPv4) + XOR-MAPPED-ADDRESS (IPv4)
+const mapped_response = [_]u8{
+    0x01, 0x01, 0x00, 0x18,
+    0x21, 0x12, 0xA4, 0x42,
+    0x00, 0x01, 0x02, 0x03,
+    0x04, 0x05, 0x06, 0x07,
+    0x08, 0x09, 0x0A, 0x0B,
+    // MAPPED-ADDRESS IPv4
+    0x00, 0x01, 0x00, 0x08,
+    0x00, 0x01, 0x80, 0x55,
+    192,  0,    2,    1,
+    // XOR-MAPPED-ADDRESS IPv4
+    0x00, 0x20, 0x00, 0x08,
+    0x00, 0x01, 0xA1, 0x47,
+    0xE1, 0x12, 0xA6, 0x43,
+};
+
+// RFC 5769 §2.1 sample binding request: SOFTWARE, PRIORITY, ICE-CONTROLLED,
+// USERNAME, MESSAGE-INTEGRITY, FINGERPRINT
+const rfc5769_request = [_]u8{
+    0x00, 0x01, 0x00, 0x58,
+    0x21, 0x12, 0xa4, 0x42,
+    0xb7, 0xe7, 0xa7, 0x01,
+    0xbc, 0x34, 0xd6, 0x86,
+    0xfa, 0x87, 0xdf, 0xae,
+    0x80, 0x22, 0x00, 0x10,
+    0x53, 0x54, 0x55, 0x4e,
+    0x20, 0x74, 0x65, 0x73,
+    0x74, 0x20, 0x63, 0x6c,
+    0x69, 0x65, 0x6e, 0x74,
+    0x00, 0x24, 0x00, 0x04,
+    0x6e, 0x00, 0x01, 0xff,
+    0x80, 0x29, 0x00, 0x08,
+    0x93, 0x2f, 0xf9, 0xb1,
+    0x51, 0x26, 0x3b, 0x36,
+    0x00, 0x06, 0x00, 0x09,
+    0x65, 0x76, 0x74, 0x6a,
+    0x3a, 0x68, 0x36, 0x76,
+    0x59, 0x20, 0x20, 0x20,
+    0x00, 0x08, 0x00, 0x14,
+    0x9a, 0xea, 0xa7, 0x0c,
+    0xbf, 0xd8, 0xcb, 0x56,
+    0x78, 0x1e, 0xf2, 0xb5,
+    0xb2, 0xd3, 0xf2, 0x49,
+    0xc1, 0xb5, 0x71, 0xa2,
+    0x80, 0x28, 0x00, 0x04,
+    0xe5, 0x7a, 0x3b, 0xcf,
+};
+
+const rfc5769_password = "VOkJxbRl1RmTxUk/WvJxBt";
+
+fn parseHeaderOnly(_: std.mem.Allocator) void {
+    const msg = stun.Message.parse(&empty_request) catch unreachable;
+    var it = msg.iterateAttributes(&.{});
+    while (it.next() catch unreachable) |attr| std.mem.doNotOptimizeAway(attr);
+    std.mem.doNotOptimizeAway(msg);
+}
+
+fn parseMappedAddresses(_: std.mem.Allocator) void {
+    const msg = stun.Message.parse(&mapped_response) catch unreachable;
+    var it = msg.iterateAttributes(&.{});
+    while (it.next() catch unreachable) |attr| std.mem.doNotOptimizeAway(attr);
+    std.mem.doNotOptimizeAway(msg);
+}
+
+fn parseRfc5769(_: std.mem.Allocator) void {
+    const msg = stun.Message.parse(&rfc5769_request) catch unreachable;
+    var it = msg.iterateAttributes(rfc5769_password);
+    while (it.next() catch unreachable) |attr| std.mem.doNotOptimizeAway(attr);
+    std.mem.doNotOptimizeAway(msg);
+}
+
+pub fn main(init: std.process.Init) !void {
+    const io = init.io;
+    const stdout: std.Io.File = .stdout();
+
+    var bench = zbench.Benchmark.init(init.gpa, .{});
+    defer bench.deinit();
+
+    try bench.add("STUN: header only", parseHeaderOnly, .{});
+    try bench.add("STUN: mapped + xor-mapped (IPv4)", parseMappedAddresses, .{});
+    try bench.add("STUN: RFC 5769 with integrity + fingerprint", parseRfc5769, .{});
+    try bench.run(io, stdout);
+}

build.zig

@@ -31,13 +31,20 @@ pub fn build(b: *std.Build) void {
         },
     });
 
+    const stun = b.addModule("stun", .{
+        .root_source_file = b.path("src/stun/stun.zig"),
+        .target = target,
+        .optimize = optimize,
+    });
+
     _ = b.addModule("protocols", .{
         .root_source_file = b.path("src/root.zig"),
         .target = target,
         .imports = &.{
             .{ .name = "rtp", .module = rtp },
             .{ .name = "sdp", .module = sdp },
             .{ .name = "rtsp", .module = rtsp },
+            .{ .name = "stun", .module = stun },
         },
     });
 
@@ -61,10 +68,17 @@ pub fn build(b: *std.Build) void {
         });
         const run_rtsp_tests = b.addRunArtifact(rtsp_tests);
 
+        const stun_tests = b.addTest(.{
+            .root_module = stun,
+            .filters = test_filters,
+        });
+        const run_stun_tests = b.addRunArtifact(stun_tests);
+
         const test_step = b.step("test", "Run tests");
         test_step.dependOn(&run_rtp_tests.step);
         test_step.dependOn(&run_sdp_tests.step);
         test_step.dependOn(&run_rtsp_tests.step);
+        test_step.dependOn(&run_stun_tests.step);
     }
 
     {
@@ -73,6 +87,7 @@ pub fn build(b: *std.Build) void {
         const benches = .{
             .{ .name = "rtp_packet", .src = "bench/rtp/packet.zig" },
             .{ .name = "sdp_session", .src = "bench/sdp/session.zig" },
+            .{ .name = "stun_message", .src = "bench/stun/message.zig" },
         };
 
         inline for (benches) |bench| {
@@ -86,6 +101,7 @@ pub fn build(b: *std.Build) void {
                         .{ .name = "zbench", .module = zbench.module("zbench") },
                         .{ .name = "rtp", .module = rtp },
                         .{ .name = "sdp", .module = sdp },
+                        .{ .name = "stun", .module = stun },
                     },
                 }),
             });

src/root.zig

@@ -1,3 +1,4 @@
 pub const rtp = @import("rtp");
 pub const sdp = @import("sdp");
 pub const rtsp = @import("rtsp");
+pub const stun = @import("stun");