1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
|
// Copyright 2026 Robby Zambito
//
// This file is part of zaprus.
//
// Zaprus is free software: you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the Free Software
// Foundation, either version 3 of the License, or (at your option) any later
// version.
//
// Zaprus is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
// A PARTICULAR PURPOSE. See the GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License along with
// Zaprus. If not, see <https://www.gnu.org/licenses/>.
socket: RawSocket,
headers: EthIpUdp,
connection: SaprusMessage,
const Connection = @This();
// 'p' as base64
const pong = "cA==";
/// Attempts to read from the network, and returns the next message, if any.
///
/// Asserts that `buf` is large enough to store the message that is received.
///
/// This will internally process management messages, and return the message
/// payload for the next non management connection message.
/// This function is ignorant to the message encoding.
pub fn next(self: *Connection, io: Io, buf: []u8) ![]const u8 {
while (true) {
log.debug("Awaiting connection message", .{});
const res = try self.socket.receive(buf);
log.debug("Received {} byte connection message", .{res.len});
const msg = SaprusMessage.parse(res[42..]) catch |err| {
log.err("Failed to parse next message: {t}\n{x}\n{x}", .{ err, res[0..], res[42..] });
return err;
};
switch (msg) {
.connection => |con_res| {
if (try con_res.management()) |mgt| {
log.debug("Received management message {t}", .{mgt});
switch (mgt) {
.ping => {
log.debug("Sending pong", .{});
try self.send(io, .{ .management = true }, pong);
log.debug("Sent pong message", .{});
},
else => |m| log.debug("Received management message that I don't know how to handle: {t}", .{m}),
}
} else {
log.debug("Payload was {s}", .{con_res.payload});
return con_res.payload;
}
},
else => |m| {
std.debug.panic("Expected connection message, instead got {x}. This means there is an error with the BPF.", .{@intFromEnum(m)});
},
}
}
}
/// Attempts to write a message to the network.
///
/// Clients should pass `.{}` for options unless you know what you are doing.
/// `buf` will be sent over the network as-is; this function is ignorant of encoding.
pub fn send(self: *Connection, io: Io, options: SaprusMessage.Connection.Options, buf: []const u8) !void {
const io_source: std.Random.IoSource = .{ .io = io };
const rand = io_source.interface();
log.debug("Sending connection message", .{});
self.connection.connection.options = options;
self.connection.connection.payload = buf;
var connection_bytes_buf: [2048]u8 = undefined;
const connection_bytes = self.connection.toBytes(&connection_bytes_buf);
self.headers.ip.id = rand.int(u16);
self.headers.setPayloadLen(connection_bytes.len);
var msg_buf: [2048]u8 = undefined;
var msg_w: Writer = .fixed(&msg_buf);
try msg_w.writeAll(&self.headers.toBytes());
try msg_w.writeAll(connection_bytes);
const full_msg = msg_w.buffered();
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;
const RawSocket = @import("./RawSocket.zig");
|
