WJWH

// Extremely hacky server program that will send a standard response
// to every client that connects, then closes the connection. Will
// issue no system calls (as measured by `strace`) after initial setup
// no matter how many requests are served.

// Yes, this program is sorely lacking in error checking. It's a toy
// and not meant to be taken seriously.

// compile with gcc no_syscall_server.c -luring

fskale

#!/usr/bin/env perl
package S3::Backup;
use Mojo::Base -base;
use Carp qw(carp croak);
use POSIX qw(strftime ceil floor);
use Fcntl qw(O_WRONLY O_APPEND O_CREAT);
use Fcntl ':mode';

#set utf8 output encoding explicitly
binmode( STDOUT, ":encoding(utf8)" );

rsp9u

OpenSSH_8.0p1, OpenSSL 1.1.1b  26 Feb 2019
debug1: Reading configuration data /home/rsp9u/.ssh/config
debug1: /home/rsp9u/.ssh/config line 1: Applying options for raspi
debug1: Reading configuration data /etc/ssh/ssh_config
debug2: resolve_canonicalize: hostname 192.168.63.10 is address
debug2: ssh_connect_direct
debug1: Connecting to 192.168.63.10 [192.168.63.10] port 50022.
debug1: Connection established.
debug1: identity file /home/rsp9u/.ssh/id_rsa type 0
debug1: identity file /home/rsp9u/.ssh/id_rsa-cert type -1

jamesfreeman959

# sefindif - Find interface definitions that have a string that matches the
# given regular expression
sefindif() {
  REGEXP="$1";
  pushd /usr/share/selinux/devel/include > /dev/null 2>&1;
  for FILE in */*.if;
  do
    awk "/(interface\(|template\()/ { NAME=\$NF; P=0 }; /${REGEXP}/ { if (P==0) {P=1; print NAME}; print };" ${FILE} | sed -e "s:^:${FILE}\: :g";
  done
  popd > /dev/null 2>&1;

ageis

security and hardening options for systemd service units

A common and reliable pattern in service unit files is thus:

NoNewPrivileges=yes
PrivateTmp=yes
PrivateDevices=yes
DevicePolicy=closed
ProtectSystem=strict

browny

/* --- Usage --- */
g++ server.c -o server
g++ client.c -o client
./server
./client 127.0.0.1

/* --- server.c --- */
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>