Initial commit

2026-03-31 16:53:11 +02:00
commit d0eba1c834
343 changed files with 34443 additions and 0 deletions
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+# security tweaks borrowed from @hlissner
+{
+  boot.kernel.sysctl = {
+    # The Magic SysRq key is a key combo that allows users connected to the
+    # system console of a Linux kernel to perform some low-level commands.
+
+    ## TCP hardening
+    # Prevent bogus ICMP errors from filling up logs.
+    "net.ipv4.icmp_ignore_bogus_error_responses" = 1;
+    # Reverse path filtering causes the kernel to do source validation of
+    # packets received from all interfaces. This can mitigate IP spoofing.
+    "net.ipv4.conf.default.rp_filter" = 1;
+    "net.ipv4.conf.all.rp_filter" = 1;
+    # Do not accept IP source route packets (we're not a router)
+    "net.ipv4.conf.all.accept_source_route" = 0;
+    "net.ipv6.conf.all.accept_source_route" = 0;
+    # Don't send ICMP redirects (again, we're not a router)
+    "net.ipv4.conf.all.send_redirects" = 0;
+    "net.ipv4.conf.default.send_redirects" = 0;
+    # Refuse ICMP redirects (MITM mitigations)
+    "net.ipv4.conf.all.accept_redirects" = 0;
+    "net.ipv4.conf.default.accept_redirects" = 0;
+    "net.ipv4.conf.all.secure_redirects" = 0;
+    "net.ipv4.conf.default.secure_redirects" = 0;
+    "net.ipv6.conf.all.accept_redirects" = 0;
+    "net.ipv6.conf.default.accept_redirects" = 0;
+    # Protects against SYN flood attacks
+    "net.ipv4.tcp_syncookies" = 1;
+    # Incomplete protection again TIME-WAIT assassination
+    "net.ipv4.tcp_rfc1337" = 1;
+
+    ## TCP optimization
+    # TCP Fast Open is a TCP extension that reduces network latency by packing
+    # data in the sender’s initial TCP SYN. Setting 3 = enable TCP Fast Open for
+    # both incoming and outgoing connections:
+    "net.ipv4.tcp_fastopen" = 3;
+
+    # Enable IPv4 forwarding for VPN/container routing
+    "net.ipv4.ip_forward" = 1;
+    # Bufferbloat mitigations + slight improvement in throughput & latency
+    "net.ipv4.tcp_congestion_control" = "bbr";
+    "net.core.default_qdisc" = "cake";
+
+    ## Network performance optimizations
+    # Increase network buffer sizes
+    "net.core.rmem_default" = 262144;
+    "net.core.rmem_max" = 134217728;
+    "net.core.wmem_default" = 262144;
+    "net.core.wmem_max" = 134217728;
+
+    # TCP buffer sizes
+    "net.ipv4.tcp_rmem" = "4096 131072 134217728";
+    "net.ipv4.tcp_wmem" = "4096 65536 134217728";
+
+    # TCP performance
+    "net.ipv4.tcp_window_scaling" = 1;
+    "net.ipv4.tcp_timestamps" = 1;
+    "net.ipv4.tcp_sack" = 1;
+    "net.ipv4.tcp_fack" = 1;
+    "net.ipv4.tcp_low_latency" = 1;
+    "net.ipv4.tcp_adv_win_scale" = 1;
+
+    # Reduce TIME_WAIT sockets
+    "net.ipv4.tcp_fin_timeout" = 15;
+    "net.ipv4.tcp_tw_reuse" = 1;
+  };
+
+  boot.kernelModules = ["tcp_bbr"];
+
+  security = {
+    # allow wayland lockers to unlock the screen
+    # userland niceness
+    rtkit.enable = true;
+    polkit.enable = true;
+
+    sudo-rs = {
+      enable = true;
+      execWheelOnly = true;
+      wheelNeedsPassword = false;
+    };
+
+    # don't ask for password for wheel group
+    sudo = {
+      wheelNeedsPassword = false;
+    };
+  };
+}