From: Steven Barth Date: Wed, 30 Oct 2013 12:37:05 +0000 (+0100) Subject: Detect "carrier up"-events and restart transaction X-Git-Tag: debian/1.1+git20160131-1~113 X-Git-Url: https://git.decadent.org.uk/gitweb/?a=commitdiff_plain;h=4a9de784477a0f0dbc04ff890e35adae02ee6e8b;p=odhcp6c.git Detect "carrier up"-events and restart transaction --- diff --git a/src/odhcp6c.c b/src/odhcp6c.c index 100ed61..1f75c50 100644 --- a/src/odhcp6c.c +++ b/src/odhcp6c.c @@ -391,6 +391,9 @@ bool odhcp6c_signal_process(void) do_signal = 0; bool ra_updated = ra_process(); + if (ra_link_up()) + do_signal = SIGUSR2; + if (ra_updated && (bound || allow_slaac_only == 0)) script_call("ra-updated"); // Immediate process urgent events else if (ra_updated && !bound && allow_slaac_only > 0) diff --git a/src/ra.c b/src/ra.c index c870279..aa03ff4 100644 --- a/src/ra.c +++ b/src/ra.c @@ -29,13 +29,26 @@ #include +#ifndef SOL_NETLINK +#define SOL_NETLINK 270 +#endif + +#ifndef NETLINK_ADD_MEMBERSHIP +#define NETLINK_ADD_MEMBERSHIP 1 +#endif + +#ifndef IFF_LOWER_UP +#define IFF_LOWER_UP 0x10000 +#endif #include "odhcp6c.h" #include "ra.h" -static int sock = -1; -static unsigned if_index = 0; +static bool nocarrier = false; + +static int sock = -1, rtnl = -1; +static int if_index = 0; static char if_name[IF_NAMESIZE] = {0}; static volatile int rs_attempt = 0; static struct in6_addr lladdr = IN6ADDR_ANY_INIT; @@ -44,11 +57,30 @@ static void ra_send_rs(int signal __attribute__((unused))); int ra_init(const char *ifname, const struct in6_addr *ifid) { + const pid_t ourpid = getpid(); sock = socket(AF_INET6, SOCK_RAW | SOCK_CLOEXEC, IPPROTO_ICMPV6); if_index = if_nametoindex(ifname); strncpy(if_name, ifname, sizeof(if_name) - 1); lladdr = *ifid; + rtnl = socket(AF_NETLINK, SOCK_DGRAM | SOCK_CLOEXEC, NETLINK_ROUTE); + struct sockaddr_nl rtnl_kernel = { .nl_family = AF_NETLINK }; + connect(rtnl, (const struct sockaddr*)&rtnl_kernel, sizeof(rtnl_kernel)); + + int val = RTNLGRP_LINK; + setsockopt(rtnl, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &val, sizeof(val)); + fcntl(rtnl, F_SETOWN, ourpid); + fcntl(rtnl, F_SETFL, fcntl(sock, F_GETFL) | O_ASYNC); + + struct { + struct nlmsghdr hdr; + struct ifinfomsg ifi; + } req = { + .hdr = {sizeof(req), RTM_GETLINK, NLM_F_REQUEST, 1, 0}, + .ifi = {.ifi_index = if_index} + }; + send(rtnl, &req, sizeof(req), 0); + // Filter ICMPv6 package types struct icmp6_filter filt; ICMP6_FILTER_SETBLOCKALL(&filt); @@ -60,7 +92,7 @@ int ra_init(const char *ifname, const struct in6_addr *ifid) setsockopt(sock, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &an, sizeof(an)); // Let the kernel compute our checksums - int val = 2; + val = 2; setsockopt(sock, IPPROTO_RAW, IPV6_CHECKSUM, &val, sizeof(val)); // This is required by RFC 4861 @@ -75,7 +107,6 @@ int ra_init(const char *ifname, const struct in6_addr *ifid) setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen(ifname)); // Add async-mode - const pid_t ourpid = getpid(); fcntl(sock, F_SETOWN, ourpid); fcntl(sock, F_SETFL, fcntl(sock, F_GETFL) | O_ASYNC); @@ -117,6 +148,39 @@ static void update_proc(const char *sect, const char *opt, uint32_t value) } +bool ra_link_up(void) +{ + struct { + struct nlmsghdr hdr; + struct ifinfomsg msg; + uint8_t pad[4000]; + } resp; + + bool ret = false; + ssize_t read; + + do { + read = recv(rtnl, &resp, sizeof(resp), MSG_DONTWAIT); + if (!NLMSG_OK(&resp.hdr, read) || resp.hdr.nlmsg_type != RTM_NEWLINK || + resp.msg.ifi_index != if_index) + continue; + + bool hascarrier = resp.msg.ifi_flags & IFF_LOWER_UP; + if (nocarrier && hascarrier) + ret = true; + + nocarrier = !hascarrier; + } while (read > 0); + + if (ret) { + syslog(LOG_NOTICE, "carrier up event on %s", if_name); + rs_attempt = 0; + ra_send_rs(SIGALRM); + } + + return ret; +} + bool ra_process(void) { bool found = false; diff --git a/src/ra.h b/src/ra.h index a31e7f6..af28d22 100644 --- a/src/ra.h +++ b/src/ra.h @@ -35,4 +35,5 @@ struct icmpv6_opt { int ra_init(const char *ifname, const struct in6_addr *ifid); +bool ra_link_up(void); bool ra_process(void);