From 750e457e3000187b85906814a2529ede24775325 Mon Sep 17 00:00:00 2001 From: Pierre Pfister Date: Fri, 8 Dec 2017 15:15:02 +0100 Subject: [PATCH] Support muliple RAs on single interface IETF is moving toward implementing IPv6 multihoming by sending multiple RAs on a single interface: - draft-ietf-intarea-provisioning-domains-00 - draft-ietf-rtgwg-enterprise-pa-multihoming-02 odhcpd supports configuration of multiple software interfaces on the same physical interface, which already advertises multiple RAs, but had two issues: - Each RA includes all the prefixes available on the interface. - Replies to sollicits with a single RA. This patch introduces the prefix_filter configuration parameter which allows filtering prefixes that are sent in a given RA, and fixes the sollicit code in order to reply with all the RAs that are configured on a given interface. Signed-off-by: Pierre Pfister --- README | 3 +++ src/config.c | 19 +++++++++++++++++++ src/odhcpd.c | 28 +++++++++++++++++++--------- src/odhcpd.h | 2 ++ src/router.c | 5 +++++ 5 files changed, 48 insertions(+), 9 deletions(-) diff --git a/README b/README index 95f59bf..0c562e6 100644 --- a/README +++ b/README @@ -134,6 +134,9 @@ ra_mtu integer 0 MTU to be advertised in RA messages ndproxy_routing bool 1 Learn routes from NDP ndproxy_slave bool 0 NDProxy external slave +prefix_filter string ::/0 Only advertise on-link prefixes within + [IPv6 prefix] the provided IPv6 prefix; others are + filtered out. Sections of type host (static leases) diff --git a/src/config.c b/src/config.c index bb885d0..409b3b8 100644 --- a/src/config.c +++ b/src/config.c @@ -62,6 +62,7 @@ enum { IFACE_ATTR_PD_CER, IFACE_ATTR_NDPROXY_ROUTING, IFACE_ATTR_NDPROXY_SLAVE, + IFACE_ATTR_PREFIX_FILTER, IFACE_ATTR_MAX }; @@ -104,6 +105,7 @@ static const struct blobmsg_policy iface_attrs[IFACE_ATTR_MAX] = { [IFACE_ATTR_RA_MTU] = { .name = "ra_mtu", .type = BLOBMSG_TYPE_INT32 }, [IFACE_ATTR_NDPROXY_ROUTING] = { .name = "ndproxy_routing", .type = BLOBMSG_TYPE_BOOL }, [IFACE_ATTR_NDPROXY_SLAVE] = { .name = "ndproxy_slave", .type = BLOBMSG_TYPE_BOOL }, + [IFACE_ATTR_PREFIX_FILTER] = { .name = "prefix_filter", .type = BLOBMSG_TYPE_STRING }, }; static const struct uci_blob_param_info iface_attr_info[IFACE_ATTR_MAX] = { @@ -720,6 +722,23 @@ int config_parse_interface(void *data, size_t len, const char *name, bool overwr if ((c = tb[IFACE_ATTR_NDPROXY_SLAVE])) iface->external = blobmsg_get_bool(c); + if ((c = tb[IFACE_ATTR_PREFIX_FILTER])) { + const char *str = blobmsg_get_string(c); + char *astr = malloc(strlen(str) + 1); + char *delim; + int l; + if (!astr || !strcpy(astr, str) || + (delim = strchr(astr, '/')) == NULL || (*(delim++) = 0) || + sscanf(delim, "%i", &l) == 0 || l > 128 || + inet_pton(AF_INET6, astr, &iface->pio_filter_addr) == 0) { + iface->pio_filter_length = 0; + } else { + iface->pio_filter_length = l; + } + if (astr) + free(astr); + } + return 0; err: diff --git a/src/odhcpd.c b/src/odhcpd.c index 97a6de9..58c4338 100644 --- a/src/odhcpd.c +++ b/src/odhcpd.c @@ -371,12 +371,6 @@ static void odhcpd_receive_packets(struct uloop_fd *u, _unused unsigned int even if (addr.ll.sll_family == AF_PACKET) destiface = addr.ll.sll_ifindex; - struct interface *iface = - odhcpd_get_interface_by_index(destiface); - - if (!iface && addr.nl.nl_family != AF_NETLINK) - continue; - char ipbuf[INET6_ADDRSTRLEN] = "kernel"; if (addr.ll.sll_family == AF_PACKET && len >= (ssize_t)sizeof(struct ip6_hdr)) @@ -386,10 +380,26 @@ static void odhcpd_receive_packets(struct uloop_fd *u, _unused unsigned int even else if (addr.in.sin_family == AF_INET) inet_ntop(AF_INET, &addr.in.sin_addr, ipbuf, sizeof(ipbuf)); - syslog(LOG_DEBUG, "Received %li Bytes from %s%%%s", (long)len, - ipbuf, (iface) ? iface->ifname : "netlink"); + // From netlink + if (addr.nl.nl_family == AF_NETLINK) { + syslog(LOG_DEBUG, "Received %li Bytes from %s%%%s", (long)len, + ipbuf, "netlink"); + e->handle_dgram(&addr, data_buf, len, NULL, dest); + return; + } else if (destiface != 0) { + struct interface *iface; + list_for_each_entry(iface, &interfaces, head) { + if (iface->ifindex != destiface) + continue; + + syslog(LOG_DEBUG, "Received %li Bytes from %s%%%s", (long)len, + ipbuf, iface->ifname); + + e->handle_dgram(&addr, data_buf, len, iface, dest); + } + } + - e->handle_dgram(&addr, data_buf, len, iface, dest); } } diff --git a/src/odhcpd.h b/src/odhcpd.h index fbfeb67..48ee51e 100644 --- a/src/odhcpd.h +++ b/src/odhcpd.h @@ -208,6 +208,8 @@ struct interface { bool ra_advrouter; bool ra_useleasetime; bool no_dynamic_dhcp; + uint8_t pio_filter_length; + struct in6_addr pio_filter_addr; // RA int learn_routes; diff --git a/src/router.c b/src/router.c index c35cd12..7bc94ed 100644 --- a/src/router.c +++ b/src/router.c @@ -380,6 +380,11 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add continue; } + if (odhcpd_bmemcmp(&addr->addr, &iface->pio_filter_addr, + iface->pio_filter_length) != 0 || + addr->prefix < iface->pio_filter_length) + continue; // PIO filtered out of this RA + struct nd_opt_prefix_info *p = NULL; for (size_t i = 0; i < pfxs_cnt; ++i) { if (addr->prefix == pfxs[i].nd_opt_pi_prefix_len && -- 2.25.1