Adversarial C2 Protocol Implemented in Zig
Detect interface and use real mac
+74
-32
+74
-32
src/main.zig
+74
-32
src/main.zig
···
147
147
}
148
148
149
149
fn setPayloadLen(self: *@This(), len: usize) void {
150
-
self.ip.len = @intCast(len + @sizeOf(@TypeOf(self.udp)) + @sizeOf(@TypeOf(self.ip)));
151
-
self.udp.len = @intCast(len + @sizeOf(@TypeOf(self.udp)));
150
+
self.ip.len = @intCast(len + (@bitSizeOf(@TypeOf(self.udp)) / 8) + (@bitSizeOf(@TypeOf(self.ip)) / 8));
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+
self.udp.len = @intCast(len + (@bitSizeOf(@TypeOf(self.udp)) / 8));
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}
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};
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+
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+
var socket: RawSocket = try .init();
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+
defer socket.deinit();
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155
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var headers: EthIpUdp = .{
156
-
.src_mac = undefined, // TODO: REAL MAC
159
+
.src_mac = socket.mac,
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.ip = .{
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.id = 0,
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.src_addr = rand.int(u32),
···
191
194
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std.debug.print("full message = {any}\n", .{full_msg});
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-
var socket: RawSocket = try .init("enp7s0");
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-
defer socket.deinit();
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try socket.send(full_msg);
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return;
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}
···
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std.debug.print("full message = {any}\n", .{full_msg});
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232
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-
var socket: RawSocket = try .init("enp7s0");
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-
defer socket.deinit();
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try socket.send(full_msg);
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234
return;
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235
}
···
268
267
const RawSocket = struct {
269
268
fd: i32,
270
269
sockaddr_ll: std.posix.sockaddr.ll,
270
+
mac: [6]u8,
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271
272
-
fn init(ifname: []const u8) !RawSocket {
273
-
const socket: i32 = @intCast(std.os.linux.socket(AF.PACKET, SOCK.RAW, 0));
272
+
const IFF_LOOPBACK = 0x8;
273
+
274
+
const ifconf = extern struct {
275
+
ifc_len: i32,
276
+
ifc_ifcu: extern union {
277
+
ifcu_buf: ?[*]u8,
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+
ifcu_req: ?[*]std.os.linux.ifreq,
279
+
},
280
+
};
281
+
282
+
fn init() !RawSocket {
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+
const socket: i32 = @intCast(std.os.linux.socket(std.posix.AF.PACKET, std.posix.SOCK.RAW, 0));
284
+
if (socket < 0) return error.SocketError;
285
+
286
+
// 1. Enumerate interfaces
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+
var ifreq_storage: [16]std.os.linux.ifreq = undefined;
288
+
var ifc = ifconf{
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+
.ifc_len = @sizeOf(@TypeOf(ifreq_storage)),
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+
.ifc_ifcu = .{ .ifcu_req = &ifreq_storage },
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+
};
274
292
275
-
var ifr: std.posix.ifreq = std.mem.zeroInit(std.posix.ifreq, .{});
276
-
@memcpy(ifr.ifrn.name[0..ifname.len], ifname);
277
-
ifr.ifrn.name[ifname.len] = 0;
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-
try std.posix.ioctl_SIOCGIFINDEX(socket, &ifr);
293
+
if (std.os.linux.ioctl(socket, std.os.linux.SIOCGIFCONF, @intFromPtr(&ifc)) != 0) {
294
+
return error.NicError;
295
+
}
296
+
297
+
const count = @divExact(ifc.ifc_len, @sizeOf(std.os.linux.ifreq));
298
+
var target_ifr: ?std.os.linux.ifreq = null;
299
+
300
+
for (ifreq_storage[0..@intCast(count)]) |ifr| {
301
+
var temp_ifr = ifr;
302
+
if (std.os.linux.ioctl(socket, std.os.linux.SIOCGIFFLAGS, @intFromPtr(&temp_ifr)) == 0) {
303
+
// Cast the packed flags to u16 to match the kernel's ifr_flags size
304
+
const flags: u16 = @bitCast(temp_ifr.ifru.flags);
305
+
if (flags & IFF_LOOPBACK != 0) continue;
306
+
307
+
target_ifr = ifr;
308
+
break;
309
+
}
310
+
}
311
+
312
+
var ifr = target_ifr orelse return error.NoInterfaceFound;
313
+
314
+
// 2. Get Interface Index
315
+
if (std.os.linux.ioctl(socket, std.os.linux.SIOCGIFINDEX, @intFromPtr(&ifr)) != 0) {
316
+
return error.NicError;
317
+
}
279
318
const ifindex: i32 = ifr.ifru.ivalue;
280
319
281
-
var rval = std.posix.errno(std.os.linux.ioctl(socket, std.os.linux.SIOCGIFFLAGS, @intFromPtr(&ifr)));
282
-
switch (rval) {
283
-
.SUCCESS => {},
284
-
else => {
285
-
return error.NicError;
286
-
},
320
+
// 3. Get Real MAC Address
321
+
if (std.os.linux.ioctl(socket, std.os.linux.SIOCGIFHWADDR, @intFromPtr(&ifr)) != 0) {
322
+
return error.NicError;
323
+
}
324
+
var mac: [6]u8 = ifr.ifru.hwaddr.data[0..6].*;
325
+
std.mem.reverse(u8, &mac);
326
+
327
+
// 4. Set Flags (Promiscuous/Broadcast)
328
+
if (std.os.linux.ioctl(socket, std.os.linux.SIOCGIFFLAGS, @intFromPtr(&ifr)) != 0) {
329
+
return error.NicError;
287
330
}
288
331
ifr.ifru.flags.BROADCAST = true;
289
332
ifr.ifru.flags.PROMISC = true;
290
-
rval = std.posix.errno(std.os.linux.ioctl(socket, std.os.linux.SIOCSIFFLAGS, @intFromPtr(&ifr)));
291
-
switch (rval) {
292
-
.SUCCESS => {},
293
-
else => {
294
-
return error.NicError;
295
-
},
333
+
if (std.os.linux.ioctl(socket, std.os.linux.SIOCSIFFLAGS, @intFromPtr(&ifr)) != 0) {
334
+
return error.NicError;
296
335
}
297
-
std.debug.print("ifindex: {}\n", .{ifindex});
336
+
298
337
const sockaddr_ll = std.posix.sockaddr.ll{
299
338
.family = std.posix.AF.PACKET,
300
339
.ifindex = ifindex,
301
340
.protocol = std.mem.nativeToBig(u16, @as(u16, std.os.linux.ETH.P.IP)),
302
-
.halen = 0, //not used
303
-
.addr = .{ 0, 0, 0, 0, 0, 0, 0, 0 }, //not used
304
-
.pkttype = 0, //not used
305
-
.hatype = 0, //not used
341
+
.halen = 0,
342
+
.addr = .{ 0, 0, 0, 0, 0, 0, 0, 0 },
343
+
.pkttype = 0,
344
+
.hatype = 0,
306
345
};
307
-
_ = std.os.linux.bind(socket, @ptrCast(&sockaddr_ll), @sizeOf(@TypeOf(sockaddr_ll)));
346
+
347
+
const bind_ret = std.os.linux.bind(socket, @ptrCast(&sockaddr_ll), @sizeOf(@TypeOf(sockaddr_ll)));
348
+
if (bind_ret != 0) return error.BindError;
308
349
309
350
return .{
310
351
.fd = socket,
311
352
.sockaddr_ll = sockaddr_ll,
353
+
.mac = mac,
312
354
};
313
355
}
314
356
···
333
375
self.fd,
334
376
buf.ptr,
335
377
buf.len,
336
-
0, // flags
378
+
0,
337
379
null,
338
380
null,
339
381
);