diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/monitor/monitor_netlink.c | 249 |
1 files changed, 244 insertions, 5 deletions
diff --git a/src/monitor/monitor_netlink.c b/src/monitor/monitor_netlink.c index 737266bf..7bc90efc 100644 --- a/src/monitor/monitor_netlink.c +++ b/src/monitor/monitor_netlink.c @@ -27,6 +27,8 @@ #include <sys/ioctl.h> #define __USE_GNU /* needed for struct ucred */ #include <sys/socket.h> +#include <netinet/in.h> +#include <arpa/inet.h> #include <unistd.h> #include <fcntl.h> @@ -43,6 +45,7 @@ #include <netlink/route/addr.h> #include <netlink/route/link.h> #include <netlink/route/rtnl.h> +#include <netlink/route/route.h> #include <netlink/handlers.h> #endif @@ -65,6 +68,13 @@ #define BUFSIZE 8 +enum nlw_msg_type { + NLW_LINK, + NLW_ROUTE, + NLW_ADDR, + NLW_OTHER +}; + struct netlink_ctx { #ifdef HAVE_LIBNL struct nl_handle *nlh; @@ -220,6 +230,26 @@ static bool discard_iff_up(const char *ifname) return false; } +static void nladdr_to_string(struct nl_addr *nl, char *buf, size_t bufsize) +{ + int addr_family; + void *addr; + + addr_family = nl_addr_get_family(nl); + if (addr_family != AF_INET && addr_family != AF_INET6) { + strncpy(buf, "unknown", bufsize); + return; + } + + addr = nl_addr_get_binary_addr(nl); + if (!addr) return; + + if (inet_ntop(addr_family, addr, buf, bufsize) == NULL) { + DEBUG(SSSDBG_MINOR_FAILURE, ("inet_ntop failed\n")); + snprintf(buf, bufsize, "unknown"); + } +} + /******************************************************************* * Wrappers for different capabilities of different libnl versions *******************************************************************/ @@ -257,6 +287,48 @@ static bool nlw_accept_message(struct nl_handle *nlh, return accept_msg; } +static bool nlw_is_addr_object(struct nl_object *obj) +{ + bool is_addr_object = true; + struct rtnl_addr *filter; + + filter = rtnl_addr_alloc(); + if (!filter) { + DEBUG(SSSDBG_CRIT_FAILURE, ("Allocation error!\n")); + is_addr_object = false; + } + + /* Ensure it's an addr object */ + if (!nlw_object_match(obj, OBJ_CAST(filter))) { + DEBUG(SSSDBG_MINOR_FAILURE, ("Not an addr object\n")); + is_addr_object = false; + } + + rtnl_addr_put(filter); + return is_addr_object; +} + +static bool nlw_is_route_object(struct nl_object *obj) +{ + bool is_route_object = true; + struct rtnl_route *filter; + + filter = rtnl_route_alloc(); + if (!filter) { + DEBUG(SSSDBG_CRIT_FAILURE, ("Allocation error!\n")); + is_route_object = false; + } + + /* Ensure it's a route object */ + if (!nlw_object_match(obj, OBJ_CAST(filter))) { + DEBUG(SSSDBG_MINOR_FAILURE, ("Not a route object\n")); + is_route_object = false; + } + + rtnl_route_put(filter); + return is_route_object; +} + static bool nlw_is_link_object(struct nl_object *obj) { bool is_link_object = true; @@ -287,19 +359,18 @@ static int nlw_enable_passcred(struct nl_handle *nlh) #endif } -static int nlw_group_subscribe(struct nl_handle *nlh) +static int nlw_group_subscribe(struct nl_handle *nlh, int group) { int ret; #ifdef HAVE_NL_SOCKET_ADD_MEMBERSHIP - ret = nl_socket_add_membership(nlh, RTNLGRP_LINK); + ret = nl_socket_add_membership(nlh, group); if (ret != 0) { DEBUG(1, ("Unable to add membership: %s\n", nl_geterror())); return ret; } #else int nlfd = nlw_get_fd(nlh); - int group = RTNLGRP_LINK; errno = 0; ret = setsockopt(nlfd, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, @@ -314,6 +385,19 @@ static int nlw_group_subscribe(struct nl_handle *nlh) return 0; } +static int nlw_groups_subscribe(struct nl_handle *nlh, int *groups) +{ + int ret; + int i; + + for (i=0; groups[i]; i++) { + ret = nlw_group_subscribe(nlh, groups[i]); + if (ret != EOK) return ret; + } + + return EOK; +} + /******************************************************************* * Callbacks for validating and receiving messages *******************************************************************/ @@ -343,10 +427,50 @@ static int event_msg_recv(struct nl_msg *msg, void *arg) } static void link_msg_handler(struct nl_object *obj, void *arg); +static void route_msg_handler(struct nl_object *obj, void *arg); +static void addr_msg_handler(struct nl_object *obj, void *arg); + +static enum nlw_msg_type message_type(struct nlmsghdr *hdr) +{ + DEBUG(SSSDBG_FUNC_DATA, ("netlink Message type: %d\n", hdr->nlmsg_type)); + switch (hdr->nlmsg_type) { + /* network interface added */ + case RTM_NEWLINK: + return NLW_LINK; + /* routing table changed */ + case RTM_NEWROUTE: + case RTM_DELROUTE: + return NLW_ROUTE; + /* IP address added or deleted */ + case RTM_NEWADDR: + case RTM_DELADDR: + return NLW_ADDR; + /* Something else happened, but we don't care (typically RTM_GET* ) */ + default: + return NLW_OTHER; + } + + return NLW_OTHER; +} static int event_msg_ready(struct nl_msg *msg, void *arg) { - nl_msg_parse(msg, &link_msg_handler, arg); + struct nlmsghdr *hdr = nlmsg_hdr(msg); + + switch (message_type(hdr)) { + case NLW_LINK: + nl_msg_parse(msg, &link_msg_handler, arg); + break; + case NLW_ROUTE: + nl_msg_parse(msg, &route_msg_handler, arg); + break; + case NLW_ADDR: + nl_msg_parse(msg, &addr_msg_handler, arg); + break; + default: + return EOK; /* Don't care */ + } + return NLW_OK; } @@ -378,6 +502,119 @@ static int nlw_set_callbacks(struct nl_handle *nlh, void *data) return ret; } +static void route_msg_debug_print(struct rtnl_route *route_obj) +{ + int prefixlen; + char buf[INET6_ADDRSTRLEN]; + struct nl_addr *nl; + + nl = rtnl_route_get_dst(route_obj); + if (nl) { + nladdr_to_string(nl, buf, INET6_ADDRSTRLEN); + prefixlen = nl_addr_get_prefixlen(nl); + } else { + strncpy(buf, "unknown", INET6_ADDRSTRLEN); + prefixlen = 0; + } + + DEBUG(SSSDBG_TRACE_LIBS, ("route idx %d flags %#X family %d addr %s/%d\n", + rtnl_route_get_oif(route_obj), rtnl_route_get_flags(route_obj), + rtnl_route_get_family(route_obj), buf, prefixlen)); +} + +/* + * If a bridge interface is configured it sets up a timer to requery for + * multicast group memberships periodically. We need to discard such + * messages. + */ +static bool route_is_multicast(struct rtnl_route *route_obj) +{ + struct nl_addr *nl; + struct in6_addr *addr6 = NULL; + struct in_addr *addr4 = NULL; + + nl = rtnl_route_get_dst(route_obj); + if (!nl) { + DEBUG(SSSDBG_MINOR_FAILURE, ("A route with no destination?\n")); + return false; + } + + if (nl_addr_get_family(nl) == AF_INET) { + addr4 = nl_addr_get_binary_addr(nl); + if (!addr4) { + return false; + } + + return IN_MULTICAST(addr4->s_addr); + } else if (nl_addr_get_family(nl) == AF_INET6) { + addr6 = nl_addr_get_binary_addr(nl); + if (!addr6) { + return false; + } + + return IN6_IS_ADDR_MULTICAST(addr6); + } + + DEBUG(SSSDBG_MINOR_FAILURE, ("Unknown route address family\n")); + return false; +} + +static void route_msg_handler(struct nl_object *obj, void *arg) +{ + struct rtnl_route *route_obj; + struct netlink_ctx *ctx = (struct netlink_ctx *) arg; + + if (!nlw_is_route_object(obj)) return; + + route_obj = (struct rtnl_route *) obj; + + if (route_is_multicast(route_obj)) { + DEBUG(SSSDBG_TRACE_INTERNAL, + ("Discarding multicast route message\n")); + return; + } + + if (debug_level & SSSDBG_TRACE_LIBS) { + route_msg_debug_print(route_obj); + } + + ctx->change_cb(ctx->cb_data); +} + +static void addr_msg_debug_print(struct rtnl_addr *addr_obj) +{ + unsigned int flags; + char str_flags[512]; + int ifidx; + struct nl_addr *local_addr; + char buf[INET6_ADDRSTRLEN]; + + flags = rtnl_addr_get_flags(addr_obj); + ifidx = rtnl_addr_get_ifindex(addr_obj); + local_addr = rtnl_addr_get_local(addr_obj); + + rtnl_addr_flags2str(flags, str_flags, 512); + nladdr_to_string(local_addr, buf, INET6_ADDRSTRLEN); + + DEBUG(SSSDBG_TRACE_LIBS, ("netlink addr message: iface idx %u " + "addr %s flags 0x%X (%s)\n", ifidx, buf, flags, str_flags)); +} + +static void addr_msg_handler(struct nl_object *obj, void *arg) +{ + struct netlink_ctx *ctx = (struct netlink_ctx *) arg; + struct rtnl_addr *addr_obj; + + if (!nlw_is_addr_object(obj)) return; + + addr_obj = (struct rtnl_addr *) obj; + if (debug_level & SSSDBG_TRACE_LIBS) { + addr_msg_debug_print(addr_obj); + } + + ctx->change_cb(ctx->cb_data); +} + static void link_msg_handler(struct nl_object *obj, void *arg) { struct netlink_ctx *ctx = (struct netlink_ctx *) arg; @@ -436,6 +673,8 @@ int setup_netlink(TALLOC_CTX *mem_ctx, struct tevent_context *ev, int ret; int nlfd; unsigned flags; + int groups[] = { RTNLGRP_LINK, RTNLGRP_IPV4_ROUTE, RTNLGRP_IPV6_ROUTE, + RTNLGRP_IPV4_IFADDR, RTNLGRP_IPV6_IFADDR, 0 }; nlctx = talloc_zero(mem_ctx, struct netlink_ctx); if (!nlctx) return ENOMEM; @@ -477,7 +716,7 @@ int setup_netlink(TALLOC_CTX *mem_ctx, struct tevent_context *ev, } /* Subscribe to the LINK group for internal carrier signals */ - ret = nlw_group_subscribe(nlctx->nlh); + ret = nlw_groups_subscribe(nlctx->nlh, groups); if (ret != 0) { DEBUG(1, ("Unable to subscribe to netlink monitor\n")); ret = EIO; |