From f53adae4eae5ad9f7343ff4a0fc68b468c981138 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Mon, 8 Apr 2013 04:01:30 +0000 Subject: [PATCH] net: ipv6: add tokenized interface identifier support This patch adds support for IPv6 tokenized IIDs, that allow for administrators to assign well-known host-part addresses to nodes whilst still obtaining global network prefix from Router Advertisements. It is currently in draft status. The primary target for such support is server platforms where addresses are usually manually configured, rather than using DHCPv6 or SLAAC. By using tokenised identifiers, hosts can still determine their network prefix by use of SLAAC, but more readily be automatically renumbered should their network prefix change. [...] The disadvantage with static addresses is that they are likely to require manual editing should the network prefix in use change. If instead there were a method to only manually configure the static identifier part of the IPv6 address, then the address could be automatically updated when a new prefix was introduced, as described in [RFC4192] for example. In such cases a DNS server might be configured with such a tokenised interface identifier of ::53, and SLAAC would use the token in constructing the interface address, using the advertised prefix. [...] http://tools.ietf.org/html/draft-chown-6man-tokenised-ipv6-identifiers-02 The implementation is partially based on top of Mark K. Thompson's proof of concept. However, it uses the Netlink interface for configuration resp. data retrival, so that it can be easily extended in future. Successfully tested by myself. Cc: Hannes Frederic Sowa Cc: YOSHIFUJI Hideaki Cc: Thomas Graf Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller --- include/net/if_inet6.h | 2 + include/uapi/linux/if_link.h | 1 + net/ipv6/addrconf.c | 87 ++++++++++++++++++++++++++++++++++++++++++-- 3 files changed, 87 insertions(+), 3 deletions(-) diff --git a/include/net/if_inet6.h b/include/net/if_inet6.h index 9356322..f1063d6 100644 --- a/include/net/if_inet6.h +++ b/include/net/if_inet6.h @@ -187,6 +187,8 @@ struct inet6_dev { struct list_head tempaddr_list; #endif + struct in6_addr token; + struct neigh_parms *nd_parms; struct inet6_dev *next; struct ipv6_devconf cnf; diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index c4edfe1..6b35c42 100644 --- a/include/uapi/linux/if_link.h +++ b/include/uapi/linux/if_link.h @@ -201,6 +201,7 @@ enum { IFLA_INET6_MCAST, /* MC things. What of them? */ IFLA_INET6_CACHEINFO, /* time values and max reasm size */ IFLA_INET6_ICMP6STATS, /* statistics (icmpv6) */ + IFLA_INET6_TOKEN, /* device token */ __IFLA_INET6_MAX }; diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index a33b157..65d8139 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -422,6 +422,7 @@ static struct inet6_dev *ipv6_add_dev(struct net_device *dev) ipv6_regen_rndid((unsigned long) ndev); } #endif + memset(ndev->token.s6_addr, 0, sizeof(ndev->token.s6_addr)); if (netif_running(dev) && addrconf_qdisc_ok(dev)) ndev->if_flags |= IF_READY; @@ -2136,8 +2137,14 @@ void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao) if (pinfo->prefix_len == 64) { memcpy(&addr, &pinfo->prefix, 8); - if (ipv6_generate_eui64(addr.s6_addr + 8, dev) && - ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) { + + if (!ipv6_addr_any(&in6_dev->token)) { + read_lock_bh(&in6_dev->lock); + memcpy(addr.s6_addr + 8, + in6_dev->token.s6_addr + 8, 8); + read_unlock_bh(&in6_dev->lock); + } else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) && + ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) { in6_dev_put(in6_dev); return; } @@ -4165,7 +4172,8 @@ static inline size_t inet6_ifla6_size(void) + nla_total_size(sizeof(struct ifla_cacheinfo)) + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */ + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */ - + nla_total_size(ICMP6_MIB_MAX * 8); /* IFLA_INET6_ICMP6STATS */ + + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */ + + nla_total_size(sizeof(struct in6_addr)); /* IFLA_INET6_TOKEN */ } static inline size_t inet6_if_nlmsg_size(void) @@ -4252,6 +4260,13 @@ static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev) goto nla_put_failure; snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla)); + nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr)); + if (nla == NULL) + goto nla_put_failure; + read_lock_bh(&idev->lock); + memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla)); + read_unlock_bh(&idev->lock); + return 0; nla_put_failure: @@ -4279,6 +4294,71 @@ static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev) return 0; } +static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token) +{ + struct in6_addr ll_addr; + struct inet6_ifaddr *ifp; + struct net_device *dev = idev->dev; + + if (token == NULL) + return -EINVAL; + if (ipv6_addr_any(token)) + return -EINVAL; + if (dev->flags & (IFF_LOOPBACK | IFF_NOARP)) + return -EINVAL; + if (idev->dead || !(idev->if_flags & IF_READY)) + return -EINVAL; + if (!ipv6_accept_ra(idev)) + return -EINVAL; + if (idev->cnf.rtr_solicits <= 0) + return -EINVAL; + + write_lock_bh(&idev->lock); + + BUILD_BUG_ON(sizeof(token->s6_addr) != 16); + memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8); + + write_unlock_bh(&idev->lock); + + ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE | IFA_F_OPTIMISTIC); + ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters); + + write_lock_bh(&idev->lock); + idev->if_flags |= IF_RS_SENT; + + /* Well, that's kinda nasty ... */ + list_for_each_entry(ifp, &idev->addr_list, if_list) { + spin_lock(&ifp->lock); + if (ipv6_addr_src_scope(&ifp->addr) == + IPV6_ADDR_SCOPE_GLOBAL) { + ifp->valid_lft = 0; + ifp->prefered_lft = 0; + } + spin_unlock(&ifp->lock); + } + + write_unlock_bh(&idev->lock); + return 0; +} + +static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla) +{ + int err = -EINVAL; + struct inet6_dev *idev = __in6_dev_get(dev); + struct nlattr *tb[IFLA_INET6_MAX + 1]; + + if (!idev) + return -EAFNOSUPPORT; + + if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL) < 0) + BUG(); + + if (tb[IFLA_INET6_TOKEN]) + err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN])); + + return err; +} + static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev, u32 portid, u32 seq, int event, unsigned int flags) { @@ -4981,6 +5061,7 @@ static struct rtnl_af_ops inet6_ops = { .family = AF_INET6, .fill_link_af = inet6_fill_link_af, .get_link_af_size = inet6_get_link_af_size, + .set_link_af = inet6_set_link_af, }; /* -- 2.7.4