Added intercommunication between namespaces.

- Added abort function.
- Added intercommunication between UE namespaces.
- Reduced code size.
- Removed default getops error messages.

tools/scripts/multi-ue.sh

@@ -2,6 +2,11 @@
 
 ue_id=-1
 
+die() {
+  echo "$@"
+  exit 1
+}
+
 create_namespace() {
   ue_id=$1
   local name="ue$ue_id"
@@ -33,27 +38,67 @@ list_namespaces() {
 }
 
 open_namespace() {
-  if [[ $ue_id -lt 1 ]]; then echo "error: no last UE processed"; exit 1; fi
+  [[ $ue_id -ge 1 ]] || die "error: no last UE processed"
   local name="ue$ue_id"
   echo "opening shell in namespace ${name}"
   echo "type 'ip netns exec $name bash' in additional terminals"
   ip netns exec $name bash
 }
 
+inter_namespace_communication() {
+    [[ $# -eq 2 ]] || die "error: expected 2 UE IDs"
+    local id1=$1
+    local id2=$2
+
+    [[ $id1 -ne $id2 ]] || die "error: UE IDs must be different"
+
+    local ns1="ue$id1"
+    local ns2="ue$id2"
+    local if1="v-inter-ue_${id1}${id2}"
+    local if2="v-inter-ue_${id2}${id1}"
+
+    ip netns list | grep -q "$ns1" || die "error: namespace $ns1 does not exist"
+
+    ip netns list | grep -q "$ns2" || die "error: namespace $ns2 does not exist"
+
+    local combo1="${id1}${id2}"
+    local combo2="${id2}${id1}"
+    
+    local subnet
+    if [[ $combo1 -gt $combo2 ]]; then
+        subnet=$combo1
+    else
+        subnet=$combo2
+    fi
+
+    echo "Creating connection between $ns1 and $ns2 with subnet 172.16.$subnet.0/24"
+    ip link add $if1 type veth peer name $if2
+    ip link set $if1 netns $ns1
+    ip link set $if2 netns $ns2
+
+    ip netns exec $ns1 ip addr add 172.16.$subnet.$combo1/24 dev $if1
+    ip netns exec $ns2 ip addr add 172.16.$subnet.$combo2/24 dev $if2
+
+    ip netns exec $ns1 ip link set dev $if1 up
+    ip netns exec $ns2 ip link set dev $if2 up
+
+    echo "Connection established between $ns1 ($ns1: 172.16.$subnet.$combo1) and $ns2 ($ns2: 172.16.$subnet.$combo2)"
+}
 usage () {
   echo "$1 -c <num>: create namespace \"ue<num>\""
   echo "$1 -d <num>: delete namespace \"ue<num>\""
   echo "$1 -e      : execute shell in last processed namespace"
   echo "$1 -l      : list namespaces"
   echo "$1 -o <num>: open shell in namespace \"ue<num>\""
+  echo "$1 -i <num1> <num2>: create inter-namespace communication between \"ue<num1>\" and \"ue<num2>\""
 }
 
 prog_name=$(basename $0)
 
-if [[ $(id -u) -ne 0 ]] ; then echo "Please run as root"; exit 1; fi
+[[ $(id -u) -eq 0 ]] || die "Please run as root"
-if [[ $# -eq 0 ]]; then echo "error: no parameters given"; usage $prog_name; exit 1; fi
+[[ $# -eq 0 ]] && { usage $prog_name; die "error: no parameters given"; }
 
-while getopts c:d:ehlo: cmd
+while getopts :c:d:i:ehlo: cmd
 do
   case "${cmd}" in
     c) create_namespace ${OPTARG};;
@@ -61,7 +106,13 @@ do
     e) open_namespace; exit;;
     h) usage ${prog_name}; exit;;
     l) list_namespaces;;
+    i) shift $((OPTIND-2))
+       [[ $# -ge 2 ]] || { usage ${prog_name}; die "error: -i requires two UE IDs"; }
+       inter_namespace_communication $1 $2
+       shift 2
+       OPTIND=1
+       ;;
     o) ue_id=${OPTARG}; open_namespace;;
-    /?) echo "Invalid option"; usage ${prog_name}; exit;;
+    ?) usage ${prog_name}; die "Invalid option: -${OPTARG}";;
   esac
 done