Factor out DHCP client support

Support for additional DHCP clients is now easy to add.

3 files changed, 89 insertions, 0 deletions

diff --git a/src/lib/dhcp/README b/src/lib/dhcp/README
new file mode 100644
index 0000000..f55a06e
--- /dev/null
+++ b/src/lib/dhcp/README
@@ -0,0 +1,34 @@
+Support for dhcp clients is implemented by files in
+
+  /usr/lib/network/dhcp/
+
+The file name determines the name of the client for the profile, so
+support for a client named dhcpcd is provided by the file:
+
+  /usr/lib/network/connections/dhcpcd
+
+Files that implement support for a connection type should NOT be
+executable. Such files should contain valid Bash code, among which two
+functions, namely <client_name>_start and <client_name>_stop. For
+the client named dhcpcd these would be:
+
+  dhcpcd_start
+  dhcpcd_stop
+
+These functions are responsible for starting and stopping the dhcp
+client. When the functions are called, three bash files are already
+sourced, so all functions and variables in those files are available.
+The readily sourced files are:
+
+  /usr/lib/network/network
+  /usr/lib/network/globals
+  /etc/netctl/<profile>
+
+Here, <profile> is the profile file specifying the desired network
+configuration.
+
+When called, the start and stop functions get as their first argument
+the version of the IP protocol that the dhcp client is expected to use.
+In the case of starting the client for IPv6, an additional second
+argument 'noaddr' may be supplied, which indicates that the dhcp client
+should configure everything but an IP address.
diff --git a/src/lib/dhcp/dhclient b/src/lib/dhcp/dhclient
new file mode 100644
index 0000000..42b5f14
--- /dev/null
+++ b/src/lib/dhcp/dhclient
@@ -0,0 +1,27 @@
+type dhclient &> /dev/null || return
+
+dhclient_start() {
+    local options pidfile="/run/dhclient$1-$Interface.pid"
+    case $1 in
+      4) options=$DhclientOptions;;
+      6) options=$DhclientOptions6;;
+      *) return 1;;
+    esac
+    [[ $2 == "noaddr" ]] && options+=" -S"
+    rm -f "$pidfile"
+    if ! do_debug dhclient -$1 -q -e "TIMEOUT=${TimeoutDHCP:-30}" -pf "$pidfile" $options "$Interface"; then
+        report_error "DHCP IPv$1 lease attempt failed on interface '$Interface'"
+        return 1
+    fi
+}
+
+dhclient_stop() {
+    local stop="-x" pidfile="/run/dhclient$1-$Interface.pid"
+    if [[ -f $pidfile ]]; then
+        is_yes "${DHCPReleaseOnStop:-no}" && stop="-r"
+        do_debug dhclient -$1 -q $stop "$Interface" -pf "$pidfile" > /dev/null
+    fi
+}
+
+
+# vim: ft=sh ts=4 et sw=4:
diff --git a/src/lib/dhcp/dhcpcd b/src/lib/dhcp/dhcpcd
new file mode 100644
index 0000000..42f33ef
--- /dev/null
+++ b/src/lib/dhcp/dhcpcd
@@ -0,0 +1,28 @@
+type dhcpcd &> /dev/null || return
+
+dhcpcd_start() {
+    if [[ $1 != "4" ]]; then
+        report_error "Using 'dhcpcd' for IPv6 is currently not possible in netctl"
+        return 1
+    fi
+    rm -f "/run/dhcpcd-$Interface".{pid,cache}
+    # If using own dns, tell dhcpcd to NOT replace resolv.conf
+    [[ $DNS ]] && DhcpcdOptions+=" -C resolv.conf"
+    do_debug dhcpcd -4qL -t "${TimeoutDHCP:-30}" $DhcpcdOptions "$Interface" |& report_debug "$(cat)"
+    # The first array value of PIPESTATUS is the exit status of dhcpcd
+    if (( PIPESTATUS != 0 )); then
+        report_error "DHCP IP lease attempt failed on interface '$Interface'"
+        return 1
+    fi
+}
+
+dhcpcd_stop() {
+    local stop="-x"
+    if [[ -f "/run/dhcpcd-$Interface.pid" ]]; then
+        is_yes "${DHCPReleaseOnStop:-no}" && stop="-k"
+        do_debug dhcpcd -q $stop "$Interface" > /dev/null
+    fi
+}
+
+
+# vim: ft=sh ts=4 et sw=4: