From ee4cc813de8c8d1007cba6080a8eec1f5300e92e Mon Sep 17 00:00:00 2001
From: mivirl <>
Date: Thu, 25 Jan 2024 12:41:17 -0600
Subject: [PATCH] Use client-specified hostname

Use client-specified hostname when the server gives a name to the
client. The name is stripped to only contain a-zA-Z and limited to
a length of 16 characters.
---
 src/client.pl | 16 +++++++++++-----
 src/server.sh |  5 ++++-
 2 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/src/client.pl b/src/client.pl
index 2ef3d23..231834d 100644
--- a/src/client.pl
+++ b/src/client.pl
@@ -48,15 +48,17 @@ sub connect_to_server {
 }
 
 sub register {
+    my ($hostname) = @_;
     my $socket = connect_to_server;
     $socket->send("register\n");
+    $socket->send("$hostname\n");
     my $response;
     foreach (1..5) {
         sleep $_;
-        $socket->recv($response, 64);
+        $socket->recv($response, 80);
         last if ($response =~ m/Key/);
     }
-    (my $clientName, my $clientKey) = $response =~ m/Name: (client_\d+)\nKey: (\d+)\n/;
+    (my $clientName, my $clientKey) = $response =~ m/Name: (client_[a-zA-Z]+_\d+)\nKey: (\d+)\n/;
 
     if (defined $clientName && defined $clientKey) {
         print_log "Register: success";
@@ -76,7 +78,7 @@ sub login {
     $socket->send("$clientKey\n");
     foreach (1..5) {
         sleep $_;
-        $socket->recv($response, 64);
+        $socket->recv($response, 80);
         last if ($response =~ m/Auth/);
     }
 
@@ -192,12 +194,16 @@ sub watch_directory {
 sub capture_packets {
     my ($clientName, $clientKey) = @_;
     my $pid = fork;
-    return if ($pid);
+    if ($pid) {
+        push @child_processes, $pid;
+        return;
+    }
     my $tcpdump = ns_system('/usr/bin/tcpdump', '-w', '/dev/shm/pcap', '-W', '10', '-G', '60', '-C', '100', '-K', '-n');
     exit;
 }
 
-my ($name, $key) = register;
+my ($hostname) = ns_system('./busybox', 'hostname');
+my ($name, $key) = register($hostname);
 #print_log "Name: $name, Key: $key";
 send_info($name, $key);
 send_log($name, $key, '/var/log/auth.log');
diff --git a/src/server.sh b/src/server.sh
index 3ea8950..685d0c5 100644
--- a/src/server.sh
+++ b/src/server.sh
@@ -61,7 +61,10 @@ if [ "$COMMAND" = "login" ]; then
     unset TMPNAME
     unset TMPKEY
 elif [ "$COMMAND" = "register" ]; then
-    CLIENTNAME="client_$(( RANDOM * 2**30 + RANDOM * 2**15 + RANDOM ))"
+    echo -n "Hostname: "
+    read -r CLIENTHOSTNAME
+    CLIENTHOSTNAME=$(echo "$CLIENTHOSTNAME" | sed 's/[^a-zA-Z]//g' | cut -c -16)
+    CLIENTNAME="client_${CLIENTHOSTNAME}_$(( RANDOM * 2**30 + RANDOM * 2**15 + RANDOM ))"
     CLIENTDIR="$SRVDIR/clients/$CLIENTNAME"
     CLIENTKEY=$(( RANDOM * 2**30 + RANDOM * 2**15 + RANDOM ))
     mkdir -p "$CLIENTDIR"
-- 
2.39.5