Chunk stdin

This makes it possible to chunk connection command output to a relay
command to direct it somewhere like discord

src/Client.zig

@@ -5,6 +5,8 @@ const Client = @This();
 
 const max_message_size = 2048;
 
+pub const max_payload_len = RawSocket.max_payload_len;
+
 socket: RawSocket,
 
 pub fn init() !Client {
@@ -95,12 +97,15 @@ pub fn connect(self: Client, io: Io, payload: []const u8) !SaprusConnection {
         },
     };
 
+    log.debug("Setting bpf filter to port {}", .{connection.connection.src});
     try self.socket.attachSaprusPortFilter(connection.connection.src);
+    log.debug("bpf set", .{});
 
     var connection_buf: [2048]u8 = undefined;
     var connection_bytes = connection.toBytes(&connection_buf);
     headers.setPayloadLen(connection_bytes.len);
 
+    log.debug("Building full message", .{});
     var full_msg = blk: {
         var msg_buf: [2048]u8 = undefined;
         var msg_w: Writer = .fixed(&msg_buf);
@@ -108,17 +113,21 @@ pub fn connect(self: Client, io: Io, payload: []const u8) !SaprusConnection {
         msg_w.writeAll(connection_bytes) catch unreachable;
         break :blk msg_w.buffered();
     };
+    log.debug("Built full message. Sending message", .{});
 
     try self.socket.send(full_msg);
     var res_buf: [4096]u8 = undefined;
 
     // Ignore response from sentinel, just accept that we got one.
+    log.debug("Awaiting handshake response", .{});
     _ = try self.socket.receive(&res_buf);
     try io.sleep(.fromMilliseconds(40), .real);
 
     headers.udp.dst_port = udp_dest_port;
     headers.ip.id = rand.int(u16);
+    headers.setPayloadLen(connection_bytes.len);
 
+    log.debug("Building final handshake message", .{});
     full_msg = blk: {
         var msg_buf: [2048]u8 = undefined;
         var msg_w: Writer = .fixed(&msg_buf);
@@ -140,3 +149,4 @@ const EthIpUdp = @import("./EthIpUdp.zig").EthIpUdp;
 const std = @import("std");
 const Io = std.Io;
 const Writer = std.Io.Writer;
+const log = std.log;

src/Connection.zig

@@ -14,12 +14,16 @@ pub fn init(socket: RawSocket, headers: EthIpUdp, connection: SaprusMessage) Con
 
 pub fn next(self: Connection, io: Io, buf: []u8) ![]const u8 {
     _ = io;
+    log.debug("Awaiting connection message", .{});
     const res = try self.socket.receive(buf);
+    log.debug("Received {} byte connection message", .{res.len});
     const connection_res = blk: {
         const msg: SaprusMessage = try .parse(res[42..]);
         break :blk msg.connection;
     };
 
+    log.debug("Payload was {s}", .{connection_res.payload});
+
     return connection_res.payload;
 }
 
@@ -29,14 +33,16 @@ pub fn send(self: *Connection, io: Io, buf: []const u8) !void {
         break :blk io_source.interface();
     };
 
+    log.debug("Sending connection message", .{});
+
     self.connection.connection.payload = buf;
     const connection_bytes = blk: {
         var connection_bytes: [2048]u8 = undefined;
         break :blk self.connection.toBytes(&connection_bytes);
     };
 
-    self.headers.setPayloadLen(connection_bytes.len);
     self.headers.ip.id = rand.int(u16);
+    self.headers.setPayloadLen(connection_bytes.len);
 
     const full_msg = blk: {
         var msg_buf: [2048]u8 = undefined;
@@ -47,12 +53,16 @@ pub fn send(self: *Connection, io: Io, buf: []const u8) !void {
     };
 
     try self.socket.send(full_msg);
+
+    log.debug("Sent {} byte connection message", .{full_msg.len});
 }
 
 const std = @import("std");
 const Io = std.Io;
 const Writer = std.Io.Writer;
 
+const log = std.log;
+
 const SaprusMessage = @import("./message.zig").Message;
 
 const EthIpUdp = @import("./EthIpUdp.zig").EthIpUdp;

src/RawSocket.zig

@@ -4,6 +4,8 @@ fd: i32,
 sockaddr_ll: std.posix.sockaddr.ll,
 mac: [6]u8,
 
+pub const max_payload_len = 1000;
+
 const Ifconf = extern struct {
     ifc_len: i32,
     ifc_ifcu: extern union {

src/main.zig

@@ -38,7 +38,6 @@ pub fn main(init: std.process.Init) !void {
     } = .{};
 
     {
-        var payload_buf: [4096]u8 = undefined;
         var i: usize = 1;
         while (i < args.len) : (i += 1) {
             if (to_option.get(args[i])) |opt| {
@@ -50,12 +49,9 @@ pub fn main(init: std.process.Init) !void {
                     .relay => {
                         i += 1;
                         if (i < args.len) {
-                            var w: Writer = .fixed(&payload_buf);
-                            try w.printBase64(args[i]);
-                            flags.relay = w.buffered();
+                            flags.relay = args[i];
                         } else {
-                            std.debug.print("-r/--relay requires a string\n", .{});
-                            return error.InvalidArguments;
+                            flags.relay = "";
                         }
                     },
                     .dest => {
@@ -70,7 +66,10 @@ pub fn main(init: std.process.Init) !void {
                     .connect => {
                         i += 1;
                         if (i < args.len) {
-                            var w: Writer = .fixed(&payload_buf);
+                            var w: Writer = blk: {
+                                var buf: [2048]u8 = undefined;
+                                break :blk .fixed(&buf);
+                            };
                             try w.printBase64(args[i]);
                             flags.connect = w.buffered();
                         } else {
@@ -94,13 +93,45 @@ pub fn main(init: std.process.Init) !void {
     defer client.deinit();
 
     if (flags.relay != null) {
-        try client.sendRelay(init.io, flags.relay.?, parseDest(flags.dest));
+        var chunk_writer_buf: [2048]u8 = undefined;
+        var chunk_writer: Writer = .fixed(&chunk_writer_buf);
+        if (flags.relay.?.len > 0) {
+            var output_iter = std.mem.window(u8, flags.relay.?, SaprusClient.max_payload_len, SaprusClient.max_payload_len);
+            while (output_iter.next()) |chunk| {
+                chunk_writer.end = 0;
+                try chunk_writer.print("{b64}", .{chunk});
+                try client.sendRelay(init.io, chunk_writer.buffered(), parseDest(flags.dest));
+                try init.io.sleep(.fromMilliseconds(40), .real);
+            }
+        } else {
+            var stdin_file: std.Io.File = .stdin();
+            var stdin_file_reader = stdin_file.reader(init.io, &.{});
+            var stdin_reader = &stdin_file_reader.interface;
+            var lim_buf: [SaprusClient.max_payload_len]u8 = undefined;
+            var limited = stdin_reader.limited(.limited(10 * lim_buf.len), &lim_buf);
+            var stdin = &limited.interface;
+
+            while (stdin.fillMore()) {
+                chunk_writer.end = 0;
+                try chunk_writer.print("{b64}", .{stdin.buffered()});
+                try client.sendRelay(init.io, chunk_writer.buffered(), parseDest(flags.dest));
+                try init.io.sleep(.fromMilliseconds(40), .real);
+                try stdin.discardAll(stdin.end);
+            } else |err| switch (err) {
+                error.EndOfStream => {
+                    log.debug("end of stdin", .{});
+                },
+                else => |e| return e,
+            }
+        }
         return;
     }
 
     if (flags.connect != null) {
         reconnect: while (true) {
+            log.debug("Starting connection", .{});
             var connection = try client.connect(init.io, flags.connect.?);
+            log.debug("Connection started", .{});
 
             while (true) {
                 var res_buf: [2048]u8 = undefined;
@@ -125,14 +156,21 @@ pub fn main(init: std.process.Init) !void {
                 var child_stderr: std.ArrayList(u8) = .empty;
                 defer child_stderr.deinit(init.gpa);
 
-                try child.collectOutput(init.gpa, &child_stdout, &child_stderr, 2048);
+                try child.collectOutput(init.gpa, &child_stdout, &child_stderr, std.math.maxInt(usize));
 
-                const b64e = std.base64.standard.Encoder;
-                var cmd_output_buf: [2048]u8 = undefined;
-                const encoded_cmd_output = b64e.encode(&cmd_output_buf, child_stdout.items);
+                // const b64e = std.base64.standard.Encoder;
+                var cmd_output: Writer = blk: {
+                    var cmd_output_buf: [2048]u8 = undefined;
+                    break :blk .fixed(&cmd_output_buf);
+                };
 
-                connection.send(init.io, encoded_cmd_output) catch continue;
-                try init.io.sleep(.fromMilliseconds(40), .real);
+                var cmd_output_window_iter = std.mem.window(u8, child_stdout.items, SaprusClient.max_payload_len, SaprusClient.max_payload_len);
+                while (cmd_output_window_iter.next()) |chunk| {
+                    cmd_output.end = 0;
+                    try cmd_output.print("{b64}", .{chunk});
+                    try connection.send(init.io, cmd_output.buffered());
+                    try init.io.sleep(.fromMilliseconds(40), .real);
+                }
             }
         }
     }
@@ -156,6 +194,7 @@ fn parseDest(in: ?[]const u8) [4]u8 {
 
 const builtin = @import("builtin");
 const std = @import("std");
+const log = std.log;
 const ArrayList = std.ArrayList;
 const StaticStringMap = std.StaticStringMap;