This change introduces the nointernet() function which may be called to
prevent a process and its descendants from communicating with publicly
routable Internet addresses. GNU Make has been modified to always call
this function. In the future Landlock Make will have a way to whitelist
subnets to override this behavior, or disable it entirely. Support is
available for Linux only. Our firewall does not require root access.
Calling nointernet() will return control to the caller inside a new
process that has a SECCOMP BPF filter installed, which traps network
related system calls. Your original process then becomes a permanent
ptrace() supervisor that monitors all processes and threads descending
from the returned child. Whenever a networking system call happens the
kernel will stop the process and wakes up the monitor, which then peeks
into the child memory to read the sockaddr_in to determine if it's ok.
The downside to doing this is that there can be only one supervisor at a
time using ptrace() on a process. So this firewall won't be enabled if
you run make under strace or inside gdb. It also makes testing tricky.
This program popped up on Hacker News recently. It's the only modern
compiler I've ever seen that doesn't have dependencies and is easily
modified. So I added all of the missing GNU extensions I like to use
which means it might be possible soon to build on non-Linux and have
third party not vendor gcc binaries.
- Emulator can now test the αcτµαlly pδrταblε εxεcµταblε bootloader
- Whipped up a webserver named redbean. It services 150k requests per
second on a single core. Bundling assets inside zip enables extremely
fast serving for two reasons. The first is that zip central directory
lookups go faster than stat() system calls. The second is that both
zip and gzip content-encoding use DEFLATE, therefore, compressed
responses can be served via the sendfile() system call which does an
in-kernel copy directly from the zip executable structure. Also note
that red bean zip executables can be deployed easily to all platforms,
since these native executables work on Linux, Mac, BSD, and Windows.
- Address sanitizer now works very well
