From 23bb091077348d3b87b9900ae3ff923cdd25a662 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Fri, 4 May 2012 12:23:41 +0200 Subject: add a ubus interface to dynamically create host routes to a particular ip address, returns the interface that the route goes through --- interface-ip.c | 152 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 150 insertions(+), 2 deletions(-) (limited to 'interface-ip.c') diff --git a/interface-ip.c b/interface-ip.c index 914ec07..ed68116 100644 --- a/interface-ip.c +++ b/interface-ip.c @@ -37,6 +37,120 @@ const struct config_param_list route_attr_list = { .params = route_attr, }; +static bool +match_if_addr(union if_addr *a1, union if_addr *a2, int mask) +{ + uint8_t *p1, *p2; + int m_bytes = (mask + 7) / 8; + uint8_t m_clear = (1 << (m_bytes * 8 - mask)) - 1; + + p1 = alloca(m_bytes); + p2 = alloca(m_bytes); + + memcpy(p1, a1, m_bytes); + memcpy(p2, a2, m_bytes); + + p1[m_bytes - 1] &= ~m_clear; + p2[m_bytes - 1] &= ~m_clear; + + return !memcmp(p1, p2, m_bytes); +} + +static bool +__find_ip_addr_target(struct interface_ip_settings *ip, union if_addr *a, bool v6) +{ + struct device_addr *addr; + + vlist_for_each_element(&ip->addr, addr, node) { + if (!addr->enabled) + continue; + + if (v6 != ((addr->flags & DEVADDR_FAMILY) == DEVADDR_INET6)) + continue; + + if (!match_if_addr(&addr->addr, a, addr->mask)) + continue; + + return true; + } + + return false; +} + +static void +__find_ip_route_target(struct interface_ip_settings *ip, union if_addr *a, + bool v6, struct device_route **res) +{ + struct device_route *route; + + vlist_for_each_element(&ip->route, route, node) { + if (!route->enabled) + continue; + + if (v6 != ((route->flags & DEVADDR_FAMILY) == DEVADDR_INET6)) + continue; + + if (!match_if_addr(&route->addr, a, route->mask)) + continue; + + if (!*res || route->mask < (*res)->mask) + *res = route; + } +} + +static bool +interface_ip_find_addr_target(struct interface *iface, union if_addr *a, bool v6) +{ + return __find_ip_addr_target(&iface->proto_ip, a, v6) || + __find_ip_addr_target(&iface->config_ip, a, v6); +} + +static void +interface_ip_find_route_target(struct interface *iface, union if_addr *a, + bool v6, struct device_route **route) +{ + __find_ip_route_target(&iface->proto_ip, a, v6, route); + __find_ip_route_target(&iface->config_ip, a, v6, route); +} + +struct interface * +interface_ip_add_target_route(union if_addr *addr, bool v6) +{ + struct interface *iface; + struct device_route *route, *r_next = NULL; + + route = calloc(1, sizeof(*route)); + if (!route) + return false; + + route->flags = v6 ? DEVADDR_INET6 : DEVADDR_INET4; + route->mask = v6 ? 128 : 32; + memcpy(&route->addr, addr, v6 ? sizeof(addr->in6) : sizeof(addr->in)); + + vlist_for_each_element(&interfaces, iface, node) { + /* look for locally addressable target first */ + if (interface_ip_find_addr_target(iface, addr, v6)) + goto done; + + /* do not stop at the first route, let the lookup compare + * masks to find the best match */ + interface_ip_find_route_target(iface, addr, v6, &r_next); + } + + if (!r_next) + return NULL; + + iface = r_next->iface; + memcpy(&route->nexthop, &r_next->nexthop, sizeof(route->nexthop)); + route->mtu = r_next->mtu; + route->metric = r_next->metric; + +done: + route->iface = iface; + vlist_add(&iface->host_routes, &route->node, &route->flags); + return iface; +} + void interface_ip_add_route(struct interface *iface, struct blob_attr *attr, bool v6) { @@ -218,6 +332,30 @@ interface_update_proto_route(struct vlist_tree *tree, } } +static void +interface_update_host_route(struct vlist_tree *tree, + struct vlist_node *node_new, + struct vlist_node *node_old) +{ + struct interface *iface; + struct device *dev; + struct device_route *route_old, *route_new; + + iface = container_of(tree, struct interface, host_routes); + dev = iface->l3_dev.dev; + + route_old = container_of(node_old, struct device_route, node); + route_new = container_of(node_new, struct device_route, node); + + if (node_old) { + system_del_route(dev, route_old); + free(route_old); + } + + if (node_new) + system_add_route(dev, route_new); +} + void interface_add_dns_server(struct interface_ip_settings *ip, const char *str) { @@ -410,14 +548,16 @@ interface_ip_update_complete(struct interface_ip_settings *ip) void interface_ip_flush(struct interface_ip_settings *ip) { + if (ip == &ip->iface->proto_ip) + vlist_flush_all(&ip->iface->host_routes); vlist_simple_flush_all(&ip->dns_servers); vlist_simple_flush_all(&ip->dns_search); vlist_flush_all(&ip->route); vlist_flush_all(&ip->addr); } -void -interface_ip_init(struct interface_ip_settings *ip, struct interface *iface) +static void +__interface_ip_init(struct interface_ip_settings *ip, struct interface *iface) { ip->iface = iface; ip->enabled = true; @@ -426,3 +566,11 @@ interface_ip_init(struct interface_ip_settings *ip, struct interface *iface) vlist_init(&ip->route, route_cmp, interface_update_proto_route); vlist_init(&ip->addr, addr_cmp, interface_update_proto_addr); } + +void +interface_ip_init(struct interface *iface) +{ + __interface_ip_init(&iface->proto_ip, iface); + __interface_ip_init(&iface->config_ip, iface); + vlist_init(&iface->host_routes, route_cmp, interface_update_host_route); +} -- cgit v1.2.3