Merge pull request #1251 from kernelkit/dhcpv6-client

Add DHCPv6 client support

Author: troglobit

board/common/rootfs/etc/udhcpc/default.script

@@ -0,0 +1 @@
+/usr/share/udhcpc/default.script

board/common/rootfs/etc/udhcpc/default6.script

@@ -0,0 +1 @@
+/usr/share/udhcpc/default6.script

board/common/rootfs/usr/share/udhcpc/default.script

@@ -104,7 +104,6 @@ case "$ACTION" in
     deconfig)
 	clr_dhcp_addresses
 	clr_dhcp_routes
-	/bin/ip link set dev $interface up
 
 	# drop info from this interface
 	rm -f "$RESOLV_CONF"

board/common/rootfs/usr/share/udhcpc/default6.script

@@ -0,0 +1,111 @@
+#!/bin/sh
+# This script expects a system with resolvconf (openresolv) and iproute2
+
+[ -z "$1" ] && echo "Error: should be called from udhcpc6" && exit 1
+
+ACTION="$1"
+RESOLV_CONF="/run/resolvconf/interfaces/${interface}-ipv6.conf"
+NTPFILE="/run/chrony/dhcp-sources.d/${interface}-ipv6.sources"
+
+[ -n "$metric" ] || metric=5
+
+if [ -z "${IF_WAIT_DELAY}" ]; then
+	IF_WAIT_DELAY=10
+fi
+
+log()
+{
+    logger -I $$ -t udhcpc6 -p user.notice "${interface}: $*"
+}
+
+dbg()
+{
+    logger -I $$ -t udhcpc6 -p user.debug "${interface}: $*"
+}
+
+err()
+{
+    logger -I $$ -t udhcpc6 -p user.err "${interface}: $*"
+}
+
+clr_dhcpv6_addresses()
+{
+    addrs=$(ip -j addr show dev $interface \
+		| jq -c '.[0].addr_info[] | select(.family == "inet6") | select(.protocol == "dhcp")')
+
+    for addr in $addrs; do
+	ip="$(echo "$addr" | jq -r '."local"')"
+	prefix="$(echo "$addr" | jq -r '."prefixlen"')"
+	log "removing $ip/$prefix"
+	ip addr del "$ip/$prefix" dev "$interface"
+    done
+}
+
+log "action $ACTION"
+case "$ACTION" in
+    deconfig)
+	clr_dhcpv6_addresses
+
+	# drop info from this interface
+	rm -f "$RESOLV_CONF"
+	rm -f "$NTPFILE"
+	;;
+
+    leasefail|nak)
+	# DHCPv6 lease failed - log it
+	err "DHCPv6 lease failed"
+	;;
+
+    renew|bound)
+	# Add IPv6 address if provided (stateful DHCPv6)
+	if [ -n "$ipv6" ]; then
+	    if /bin/ip addr add dev $interface $ipv6 proto dhcp; then
+		log "assigned address $ipv6"
+	    fi
+	fi
+
+	# Handle delegated prefix (prefix delegation)
+	if [ -n "$ipv6prefix" ]; then
+	    log "received delegated prefix $ipv6prefix"
+	    # Prefix delegation handling could be added here
+	    # For now, just log it - actual routing/distribution
+	    # would need additional configuration
+	fi
+
+	# drop info from this interface
+	truncate -s 0 "$RESOLV_CONF"
+
+	# DHCPv6 domain search list (option 24)
+	if [ -n "$search" ]; then
+	    dbg "adding search $search"
+	    echo "search $search # $interface" >> $RESOLV_CONF
+	fi
+
+	# DHCPv6 DNS servers (option 23)
+	if [ -n "$dns" ]; then
+	    for i in $dns ; do
+		dbg "adding dns $i"
+		echo "nameserver $i # $interface" >> $RESOLV_CONF
+	    done
+	    resolvconf -u
+	fi
+
+	# NTP servers (option 56)
+	if [ -n "$ntpsrv" ]; then
+	    truncate -s 0 "$NTPFILE"
+	    for srv in $ntpsrv; do
+		dbg "got NTP server $srv"
+		echo "server $srv iburst" >> "$NTPFILE"
+	    done
+	    chronyc reload sources >/dev/null
+	fi
+	;;
+esac
+
+HOOK_DIR="$0.d"
+for hook in "${HOOK_DIR}/"*; do
+    [ -f "${hook}" -a -x "${hook}" ] || continue
+    "${hook}" "$ACTION"
+done
+
+exit 0

doc/ChangeLog.md

@@ -31,6 +31,10 @@ All notable changes to the project are documented in this file.
   now enabled using a presence container instead of a separate `enabled` leaf
 - The `enabled` nore for IPv4 autoconf (ZeroConf) has been dropped, `autoconf`
   is now a presence container.  Configuration automatically migrated on upgrade
+- Add DHCPv6 client support for per-interface IPv6 configuration, augmenting
+  `/interfaces/interface[name]/ipv6/infix-dhcpv6-client:dhcp`, issue #1110
+- Fix namespace for DHCPv4 client YANG module from `urn:ietf:params:xml:ns:yang`
+  to `urn:infix:params:xml:ns:yang` to properly reflect custom implementation
 - Improvements to `sdcard.img` generation, useful for developers mostly:
    - The NanoPi R2S bootloader is now automatically built and uploaded to
      the [`latest-boot` release][lastest-boot] tag

doc/networking.md

@@ -959,16 +959,55 @@ Client Configuration](system.md#ntp-client-configuration) section.
 
 Multiple address assignment methods are available:
 
-| **Type**         | **Yang Model** | **Description**                                                                                                                                   |
-|:---------------- |:-------------- |:------------------------------------------------------------------------------------------------------------------------------------------------- |
-| static           | ietf-ip        | Static assignment of IPv6 address, e.g., *2001:db8:0:1::1/64*                                                                                     |
-| link-local       | ietf-ip[^2]    | (RFC4862) Auto-configured link-local IPv6 address (*fe80::0* prefix + interface identifier, e.g., *fe80::ccd2:82ff:fe52:728b/64*)                 |
-| global auto-conf | ietf-ip        | (RFC4862) Auto-configured (stateless) global IPv6 address (prefix from router + interface identifier, e.g., *2001:db8:0:1:ccd2:82ff:fe52:728b/64* |
+| **Type**         | **Yang Model**       | **Description**                                                                                                                                   |
+|:---------------- |:-------------------- |:------------------------------------------------------------------------------------------------------------------------------------------------- |
+| static           | ietf-ip              | Static assignment of IPv6 address, e.g., *2001:db8:0:1::1/64*                                                                                     |
+| link-local       | ietf-ip[^2]          | (RFC4862) Auto-configured link-local IPv6 address (*fe80::0* prefix + interface identifier, e.g., *fe80::ccd2:82ff:fe52:728b/64*)                 |
+| global auto-conf | ietf-ip              | (RFC4862) Auto-configured (stateless) global IPv6 address (prefix from router + interface identifier, e.g., *2001:db8:0:1:ccd2:82ff:fe52:728b/64* |
+| dhcp             | infix-dhcpv6-client  | Assignment of IPv6 address by DHCPv6 server, e.g., *2001:db8::42/128*                                                                             |
 
 Both for *link-local* and *global auto-configuration*, it is possible
 to auto-configure using a random suffix instead of the interface
 identifier.
 
+> [!NOTE]
+> The DHCPv6 address method is only available for *LAN* interfaces
+> (Ethernet, virtual Ethernet (veth), bridge, link aggregates, etc.)
+
+Supported DHCPv6 (request) options, configurability (Cfg) and defaults,
+are listed below.  Configurable options can be disabled on a per client
+interface basis, some options, like `client-id` and `client-fqdn`, are
+possible to set the value of as well.
+
+| **Opt** | **Name**                   | **Cfg** | **Description**                                        |
+|---------|----------------------------|---------|--------------------------------------------------------|
+| 1       | `client-id`                | Yes     | Client identifier (DUID), auto-generated by default    |
+| 2       | `server-id`                | Yes     | Server identifier (DUID)                               |
+| 23      | `dns-server`               | Yes     | DNS recursive name servers, static ones take precedence|
+| 24      | `domain-search`            | Yes     | Domain search list                                     |
+| 25      | `ia-pd`                    | Yes     | Prefix delegation for downstream networks              |
+| 31      | `sntp-server`              | Yes     | Simple Network Time Protocol servers                   |
+| 32      | `information-refresh-time` | Yes     | Refresh time for stateless DHCPv6                      |
+| 39      | `client-fqdn`              | Yes     | Client FQDN, request DNS update from server            |
+| 56      | `ntp-server`               | Yes     | NTP time servers, static ones take precedence          |
+|         |                            |         |                                                        |
+
+**Default:** `dns-server`, `domain-search`, `ntp-server`
+
+DHCPv6 supports both **stateful** (address assignment) and **stateless**
+(information-only) modes:
+
+- **Stateful DHCPv6**: The server assigns IPv6 addresses to clients. This is
+  the default mode when enabling the DHCPv6 client.
+- **Stateless DHCPv6**: Used with SLAAC (Stateless Address Autoconfiguration)
+  when only configuration information (DNS, NTP, etc.) is needed. Enable with
+  the `information-only` setting.
+
+When configuring a DHCPv6 client, ensure that the NTP client is enabled
+for the `ntp-server` DHCPv6 option to be processed correctly.  If the
+NTP client is not enabled, any NTP servers provided by the DHCPv6 server
+will be ignored. For details on how to enable the NTP client, see the
+[NTP Client Configuration](system.md#ntp-client-configuration) section.
 
 ### Examples
 
@@ -1080,6 +1119,63 @@ Other useful DHCP options include:
 
 For advanced usage with vendor-specific options, see the YANG model.
 
+#### Use of DHCPv6 for IPv6 address assignment
+
+![Using DHCPv6 for IPv6 address assignment](img/ip-address-example-ipv6-dhcp.svg)
+
+    admin@example:/> configure
+    admin@example:/config/> edit interface eth0 ipv6
+    admin@example:/config/interface/eth0/ipv6/> set dhcp
+    admin@example:/config/interface/eth0/ipv6/> leave
+    admin@example:/> show interface
+    INTERFACE       PROTOCOL   STATE       DATA
+    eth0            ethernet   UP          02:00:00:00:00:00
+                    ipv6                   2001:db8::42/128 (dhcp)
+                    ipv6                   fe80::ff:fe00:0/64 (link-layer)
+    lo              ethernet   UP          00:00:00:00:00:00
+                    ipv4                   127.0.0.1/8 (static)
+                    ipv6                   ::1/128 (static)
+    admin@example:/>
+
+The resulting address (2001:db8::42/128) is of type *dhcp*.
+
+To configure DHCPv6 client options, such as requesting prefix delegation
+for downstream networks, you can specify options:
+
+```
+admin@example:/> configure
+admin@example:/config/> edit interface eth0 ipv6 dhcp
+admin@example:/config/interface/eth0/ipv6/dhcp/> set option ia-pd
+admin@example:/config/interface/eth0/ipv6/dhcp/> set option dns-server
+admin@example:/config/interface/eth0/ipv6/dhcp/> show
+option dns-server;
+option ia-pd;
+admin@example:/config/interface/eth0/ipv6/dhcp/> leave
+admin@example:/>
+```
+
+For stateless DHCPv6 (used with SLAAC to get only configuration information):
+
+```
+admin@example:/> configure
+admin@example:/config/> edit interface eth0 ipv6 dhcp
+admin@example:/config/interface/eth0/ipv6/dhcp/> set information-only true
+admin@example:/config/interface/eth0/ipv6/dhcp/> show
+information-only true;
+option dns-server;
+option domain-search;
+admin@example:/config/interface/eth0/ipv6/dhcp/> leave
+admin@example:/>
+```
+
+Other useful DHCPv6 options include:
+
+- `duid` - Set a specific DHCPv6 Unique Identifier (auto-generated by default)
+- `client-fqdn` - Request the server to update DNS records with client's FQDN
+- `route-preference` - Set the administrative distance for DHCPv6-learned routes (default: 5)
+
+For advanced usage with vendor-specific options, see the YANG model.
+
 #### Disabling IPv6 link-local address(es)
 
 The (only) way to disable IPv6 link-local addresses is by disabling IPv6

src/confd/src/Makefile.am

@@ -45,6 +45,7 @@ confd_plugin_la_SOURCES =			\
 	ietf-routing.c				\
 	infix-dhcp-common.c			\
 	infix-dhcp-client.c			\
+	infix-dhcpv6-client.c			\
 	infix-dhcp-server.c			\
 	infix-factory.c				\
 	infix-firewall.c			\

src/confd/src/core.c

@@ -198,6 +198,10 @@ static int change_cb(sr_session_ctx_t *session, uint32_t sub_id, const char *mod
 	if ((rc = infix_dhcp_client_change(session, config, diff, event, confd)))
 		goto free_diff;
 
+	/* infix-dhcpv6-client*/
+	if ((rc = infix_dhcpv6_client_change(session, config, diff, event, confd)))
+		goto free_diff;
+
 	/* ietf-keystore */
 	if ((rc = ietf_keystore_change(session, config, diff, event, confd)))
 		goto free_diff;
@@ -428,10 +432,6 @@ int sr_plugin_init_cb(sr_session_ctx_t *session, void **priv)
 		goto err;
 
 	rc = infix_dhcp_server_candidate_init(&confd);
-	if (rc)
-		goto err;
-
-	rc = infix_dhcp_client_candidate_init(&confd);
 	if (rc)
 		goto err;
 	/* YOUR_INIT GOES HERE */

src/confd/src/core.h

@@ -204,12 +204,11 @@ static inline int infix_containers_rpc_init(struct confd *confd) { return 0; }
 static inline int infix_containers_change(sr_session_ctx_t *session, struct lyd_node *config, struct lyd_node *diff, sr_event_t event, struct confd *confd) { return 0; }
 #endif
 
-/* infix-dhcp-common.c */
-int dhcp_option_lookup(const struct lyd_node *id);
-
 /* infix-dhcp-client.c */
 int infix_dhcp_client_change(sr_session_ctx_t *session, struct lyd_node *config, struct lyd_node *diff, sr_event_t event, struct confd *confd);
-int infix_dhcp_client_candidate_init(struct confd *confd);
+
+/* infix-dhcpv6-client.c */
+int infix_dhcpv6_client_change(sr_session_ctx_t *session, struct lyd_node *config, struct lyd_node *diff, sr_event_t event, struct confd *confd);
 
 /* infix-dhcp-server.c */
 int infix_dhcp_server_candidate_init(struct confd *confd);

src/confd/src/ietf-interfaces.c

@@ -160,6 +160,10 @@ static int ifchange_cand(sr_session_ctx_t *session, uint32_t sub_id, const char
 		if (err)
 			break;
 
+		err = ifchange_cand_infer_dhcp(session, new->xpath);
+		if (err)
+			break;
+
 		err = cni_ifchange_cand_infer_type(session, new->xpath);
 		if (err)
 			break;