d61e7e5e1f
The dhcp server is systemd-networkd, and the dhcp plugin can request an ip but can not renew it. The systemd-networkd just ignore the renew request. ``` 2024/09/14 21:46:00 no DHCP packet received within 10s 2024/09/14 21:46:00 retrying in 31.529038 seconds 2024/09/14 21:46:42 no DHCP packet received within 10s 2024/09/14 21:46:42 retrying in 63.150490 seconds 2024/09/14 21:47:45 98184616c91f15419f5cacd012697f85afaa2daeb5d3233e28b0ec21589fb45a/iot/eth1: no more tries 2024/09/14 21:47:45 98184616c91f15419f5cacd012697f85afaa2daeb5d3233e28b0ec21589fb45a/iot/eth1: renewal time expired, rebinding 2024/09/14 21:47:45 Link "eth1" down. Attempting to set up 2024/09/14 21:47:45 98184616c91f15419f5cacd012697f85afaa2daeb5d3233e28b0ec21589fb45a/iot/eth1: lease rebound, expiration is 2024-09-14 22:47:45.309270751 +0800 CST m=+11730.048516519 ``` Follow the https://datatracker.ietf.org/doc/html/rfc2131#section-4.3.6, following options must not be sent in renew - Requested IP Address - Server Identifier Since the upstream code has been inactive for 6 years, we should switch to another dhcpv4 library. The new selected one is https://github.com/insomniacslk/dhcp. Signed-off-by: Songmin Li <lisongmin@protonmail.com>
105 lines
2.3 KiB
Go
105 lines
2.3 KiB
Go
package dhcpv4
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import (
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"fmt"
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"net"
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"strings"
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"github.com/u-root/uio/uio"
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)
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// Route is a classless static route as per RFC 3442.
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type Route struct {
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// Dest is the destination network.
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Dest *net.IPNet
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// Router is the router to use for the given destination network.
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Router net.IP
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}
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// Marshal implements uio.Marshaler.
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//
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// Format described in RFC 3442:
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//
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// <size of mask in number of bits>
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// <destination address, omitting octets that must be zero per mask>
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// <route IP>
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func (r Route) Marshal(buf *uio.Lexer) {
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ones, _ := r.Dest.Mask.Size()
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buf.Write8(uint8(ones))
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// Only write the non-zero octets.
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dstLen := (ones + 7) / 8
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buf.WriteBytes(r.Dest.IP.To4()[:dstLen])
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buf.WriteBytes(r.Router.To4())
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}
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// Unmarshal implements uio.Unmarshaler.
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func (r *Route) Unmarshal(buf *uio.Lexer) error {
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maskSize := buf.Read8()
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if maskSize > 32 {
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return fmt.Errorf("invalid mask length %d in route option", maskSize)
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}
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r.Dest = &net.IPNet{
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IP: make([]byte, net.IPv4len),
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Mask: net.CIDRMask(int(maskSize), 32),
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}
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dstLen := (maskSize + 7) / 8
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buf.ReadBytes(r.Dest.IP[:dstLen])
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r.Router = buf.CopyN(net.IPv4len)
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return buf.Error()
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}
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// String prints the destination network and router IP.
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func (r *Route) String() string {
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return fmt.Sprintf("route to %s via %s", r.Dest, r.Router)
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}
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// Routes is a collection of network routes.
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type Routes []*Route
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// FromBytes parses routes from a set of bytes as described by RFC 3442.
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func (r *Routes) FromBytes(p []byte) error {
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buf := uio.NewBigEndianBuffer(p)
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for buf.Has(1) {
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var route Route
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if err := route.Unmarshal(buf); err != nil {
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return err
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}
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*r = append(*r, &route)
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}
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return buf.FinError()
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}
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// ToBytes marshals a set of routes as described by RFC 3442.
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func (r Routes) ToBytes() []byte {
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buf := uio.NewBigEndianBuffer(nil)
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for _, route := range r {
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route.Marshal(buf)
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}
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return buf.Data()
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}
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// String prints all routes.
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func (r Routes) String() string {
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s := make([]string, 0, len(r))
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for _, route := range r {
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s = append(s, route.String())
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}
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return strings.Join(s, "; ")
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}
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// OptClasslessStaticRoute returns a new DHCPv4 Classless Static Route
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// option.
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//
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// The Classless Static Route option is described by RFC 3442.
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func OptClasslessStaticRoute(routes ...*Route) Option {
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return Option{
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Code: OptionClasslessStaticRoute,
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Value: Routes(routes),
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}
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}
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