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-rw-r--r--net/ipv6/addrlabel.c652
1 files changed, 652 insertions, 0 deletions
diff --git a/net/ipv6/addrlabel.c b/net/ipv6/addrlabel.c
new file mode 100644
index 000000000..17ac45aa7
--- /dev/null
+++ b/net/ipv6/addrlabel.c
@@ -0,0 +1,652 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * IPv6 Address Label subsystem
+ * for the IPv6 "Default" Source Address Selection
+ *
+ * Copyright (C)2007 USAGI/WIDE Project
+ */
+/*
+ * Author:
+ * YOSHIFUJI Hideaki @ USAGI/WIDE Project <yoshfuji@linux-ipv6.org>
+ */
+
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/rcupdate.h>
+#include <linux/in6.h>
+#include <linux/slab.h>
+#include <net/addrconf.h>
+#include <linux/if_addrlabel.h>
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
+
+#if 0
+#define ADDRLABEL(x...) printk(x)
+#else
+#define ADDRLABEL(x...) do { ; } while (0)
+#endif
+
+/*
+ * Policy Table
+ */
+struct ip6addrlbl_entry {
+ struct in6_addr prefix;
+ int prefixlen;
+ int ifindex;
+ int addrtype;
+ u32 label;
+ struct hlist_node list;
+ struct rcu_head rcu;
+};
+
+/*
+ * Default policy table (RFC6724 + extensions)
+ *
+ * prefix addr_type label
+ * -------------------------------------------------------------------------
+ * ::1/128 LOOPBACK 0
+ * ::/0 N/A 1
+ * 2002::/16 N/A 2
+ * ::/96 COMPATv4 3
+ * ::ffff:0:0/96 V4MAPPED 4
+ * fc00::/7 N/A 5 ULA (RFC 4193)
+ * 2001::/32 N/A 6 Teredo (RFC 4380)
+ * 2001:10::/28 N/A 7 ORCHID (RFC 4843)
+ * fec0::/10 N/A 11 Site-local
+ * (deprecated by RFC3879)
+ * 3ffe::/16 N/A 12 6bone
+ *
+ * Note: 0xffffffff is used if we do not have any policies.
+ * Note: Labels for ULA and 6to4 are different from labels listed in RFC6724.
+ */
+
+#define IPV6_ADDR_LABEL_DEFAULT 0xffffffffUL
+
+static const __net_initconst struct ip6addrlbl_init_table
+{
+ const struct in6_addr *prefix;
+ int prefixlen;
+ u32 label;
+} ip6addrlbl_init_table[] = {
+ { /* ::/0 */
+ .prefix = &in6addr_any,
+ .label = 1,
+ }, { /* fc00::/7 */
+ .prefix = &(struct in6_addr){ { { 0xfc } } } ,
+ .prefixlen = 7,
+ .label = 5,
+ }, { /* fec0::/10 */
+ .prefix = &(struct in6_addr){ { { 0xfe, 0xc0 } } },
+ .prefixlen = 10,
+ .label = 11,
+ }, { /* 2002::/16 */
+ .prefix = &(struct in6_addr){ { { 0x20, 0x02 } } },
+ .prefixlen = 16,
+ .label = 2,
+ }, { /* 3ffe::/16 */
+ .prefix = &(struct in6_addr){ { { 0x3f, 0xfe } } },
+ .prefixlen = 16,
+ .label = 12,
+ }, { /* 2001::/32 */
+ .prefix = &(struct in6_addr){ { { 0x20, 0x01 } } },
+ .prefixlen = 32,
+ .label = 6,
+ }, { /* 2001:10::/28 */
+ .prefix = &(struct in6_addr){ { { 0x20, 0x01, 0x00, 0x10 } } },
+ .prefixlen = 28,
+ .label = 7,
+ }, { /* ::ffff:0:0 */
+ .prefix = &(struct in6_addr){ { { [10] = 0xff, [11] = 0xff } } },
+ .prefixlen = 96,
+ .label = 4,
+ }, { /* ::/96 */
+ .prefix = &in6addr_any,
+ .prefixlen = 96,
+ .label = 3,
+ }, { /* ::1/128 */
+ .prefix = &in6addr_loopback,
+ .prefixlen = 128,
+ .label = 0,
+ }
+};
+
+/* Find label */
+static bool __ip6addrlbl_match(const struct ip6addrlbl_entry *p,
+ const struct in6_addr *addr,
+ int addrtype, int ifindex)
+{
+ if (p->ifindex && p->ifindex != ifindex)
+ return false;
+ if (p->addrtype && p->addrtype != addrtype)
+ return false;
+ if (!ipv6_prefix_equal(addr, &p->prefix, p->prefixlen))
+ return false;
+ return true;
+}
+
+static struct ip6addrlbl_entry *__ipv6_addr_label(struct net *net,
+ const struct in6_addr *addr,
+ int type, int ifindex)
+{
+ struct ip6addrlbl_entry *p;
+
+ hlist_for_each_entry_rcu(p, &net->ipv6.ip6addrlbl_table.head, list) {
+ if (__ip6addrlbl_match(p, addr, type, ifindex))
+ return p;
+ }
+ return NULL;
+}
+
+u32 ipv6_addr_label(struct net *net,
+ const struct in6_addr *addr, int type, int ifindex)
+{
+ u32 label;
+ struct ip6addrlbl_entry *p;
+
+ type &= IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK;
+
+ rcu_read_lock();
+ p = __ipv6_addr_label(net, addr, type, ifindex);
+ label = p ? p->label : IPV6_ADDR_LABEL_DEFAULT;
+ rcu_read_unlock();
+
+ ADDRLABEL(KERN_DEBUG "%s(addr=%pI6, type=%d, ifindex=%d) => %08x\n",
+ __func__, addr, type, ifindex, label);
+
+ return label;
+}
+
+/* allocate one entry */
+static struct ip6addrlbl_entry *ip6addrlbl_alloc(const struct in6_addr *prefix,
+ int prefixlen, int ifindex,
+ u32 label)
+{
+ struct ip6addrlbl_entry *newp;
+ int addrtype;
+
+ ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u)\n",
+ __func__, prefix, prefixlen, ifindex, (unsigned int)label);
+
+ addrtype = ipv6_addr_type(prefix) & (IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK);
+
+ switch (addrtype) {
+ case IPV6_ADDR_MAPPED:
+ if (prefixlen > 96)
+ return ERR_PTR(-EINVAL);
+ if (prefixlen < 96)
+ addrtype = 0;
+ break;
+ case IPV6_ADDR_COMPATv4:
+ if (prefixlen != 96)
+ addrtype = 0;
+ break;
+ case IPV6_ADDR_LOOPBACK:
+ if (prefixlen != 128)
+ addrtype = 0;
+ break;
+ }
+
+ newp = kmalloc(sizeof(*newp), GFP_KERNEL);
+ if (!newp)
+ return ERR_PTR(-ENOMEM);
+
+ ipv6_addr_prefix(&newp->prefix, prefix, prefixlen);
+ newp->prefixlen = prefixlen;
+ newp->ifindex = ifindex;
+ newp->addrtype = addrtype;
+ newp->label = label;
+ INIT_HLIST_NODE(&newp->list);
+ return newp;
+}
+
+/* add a label */
+static int __ip6addrlbl_add(struct net *net, struct ip6addrlbl_entry *newp,
+ int replace)
+{
+ struct ip6addrlbl_entry *last = NULL, *p = NULL;
+ struct hlist_node *n;
+ int ret = 0;
+
+ ADDRLABEL(KERN_DEBUG "%s(newp=%p, replace=%d)\n", __func__, newp,
+ replace);
+
+ hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
+ if (p->prefixlen == newp->prefixlen &&
+ p->ifindex == newp->ifindex &&
+ ipv6_addr_equal(&p->prefix, &newp->prefix)) {
+ if (!replace) {
+ ret = -EEXIST;
+ goto out;
+ }
+ hlist_replace_rcu(&p->list, &newp->list);
+ kfree_rcu(p, rcu);
+ goto out;
+ } else if ((p->prefixlen == newp->prefixlen && !p->ifindex) ||
+ (p->prefixlen < newp->prefixlen)) {
+ hlist_add_before_rcu(&newp->list, &p->list);
+ goto out;
+ }
+ last = p;
+ }
+ if (last)
+ hlist_add_behind_rcu(&newp->list, &last->list);
+ else
+ hlist_add_head_rcu(&newp->list, &net->ipv6.ip6addrlbl_table.head);
+out:
+ if (!ret)
+ net->ipv6.ip6addrlbl_table.seq++;
+ return ret;
+}
+
+/* add a label */
+static int ip6addrlbl_add(struct net *net,
+ const struct in6_addr *prefix, int prefixlen,
+ int ifindex, u32 label, int replace)
+{
+ struct ip6addrlbl_entry *newp;
+ int ret = 0;
+
+ ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u, replace=%d)\n",
+ __func__, prefix, prefixlen, ifindex, (unsigned int)label,
+ replace);
+
+ newp = ip6addrlbl_alloc(prefix, prefixlen, ifindex, label);
+ if (IS_ERR(newp))
+ return PTR_ERR(newp);
+ spin_lock(&net->ipv6.ip6addrlbl_table.lock);
+ ret = __ip6addrlbl_add(net, newp, replace);
+ spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
+ if (ret)
+ kfree(newp);
+ return ret;
+}
+
+/* remove a label */
+static int __ip6addrlbl_del(struct net *net,
+ const struct in6_addr *prefix, int prefixlen,
+ int ifindex)
+{
+ struct ip6addrlbl_entry *p = NULL;
+ struct hlist_node *n;
+ int ret = -ESRCH;
+
+ ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
+ __func__, prefix, prefixlen, ifindex);
+
+ hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
+ if (p->prefixlen == prefixlen &&
+ p->ifindex == ifindex &&
+ ipv6_addr_equal(&p->prefix, prefix)) {
+ hlist_del_rcu(&p->list);
+ kfree_rcu(p, rcu);
+ ret = 0;
+ break;
+ }
+ }
+ return ret;
+}
+
+static int ip6addrlbl_del(struct net *net,
+ const struct in6_addr *prefix, int prefixlen,
+ int ifindex)
+{
+ struct in6_addr prefix_buf;
+ int ret;
+
+ ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
+ __func__, prefix, prefixlen, ifindex);
+
+ ipv6_addr_prefix(&prefix_buf, prefix, prefixlen);
+ spin_lock(&net->ipv6.ip6addrlbl_table.lock);
+ ret = __ip6addrlbl_del(net, &prefix_buf, prefixlen, ifindex);
+ spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
+ return ret;
+}
+
+/* add default label */
+static int __net_init ip6addrlbl_net_init(struct net *net)
+{
+ struct ip6addrlbl_entry *p = NULL;
+ struct hlist_node *n;
+ int err;
+ int i;
+
+ ADDRLABEL(KERN_DEBUG "%s\n", __func__);
+
+ spin_lock_init(&net->ipv6.ip6addrlbl_table.lock);
+ INIT_HLIST_HEAD(&net->ipv6.ip6addrlbl_table.head);
+
+ for (i = 0; i < ARRAY_SIZE(ip6addrlbl_init_table); i++) {
+ err = ip6addrlbl_add(net,
+ ip6addrlbl_init_table[i].prefix,
+ ip6addrlbl_init_table[i].prefixlen,
+ 0,
+ ip6addrlbl_init_table[i].label, 0);
+ if (err)
+ goto err_ip6addrlbl_add;
+ }
+ return 0;
+
+err_ip6addrlbl_add:
+ hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
+ hlist_del_rcu(&p->list);
+ kfree_rcu(p, rcu);
+ }
+ return err;
+}
+
+static void __net_exit ip6addrlbl_net_exit(struct net *net)
+{
+ struct ip6addrlbl_entry *p = NULL;
+ struct hlist_node *n;
+
+ /* Remove all labels belonging to the exiting net */
+ spin_lock(&net->ipv6.ip6addrlbl_table.lock);
+ hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
+ hlist_del_rcu(&p->list);
+ kfree_rcu(p, rcu);
+ }
+ spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
+}
+
+static struct pernet_operations ipv6_addr_label_ops = {
+ .init = ip6addrlbl_net_init,
+ .exit = ip6addrlbl_net_exit,
+};
+
+int __init ipv6_addr_label_init(void)
+{
+ return register_pernet_subsys(&ipv6_addr_label_ops);
+}
+
+void ipv6_addr_label_cleanup(void)
+{
+ unregister_pernet_subsys(&ipv6_addr_label_ops);
+}
+
+static const struct nla_policy ifal_policy[IFAL_MAX+1] = {
+ [IFAL_ADDRESS] = { .len = sizeof(struct in6_addr), },
+ [IFAL_LABEL] = { .len = sizeof(u32), },
+};
+
+static bool addrlbl_ifindex_exists(struct net *net, int ifindex)
+{
+
+ struct net_device *dev;
+
+ rcu_read_lock();
+ dev = dev_get_by_index_rcu(net, ifindex);
+ rcu_read_unlock();
+
+ return dev != NULL;
+}
+
+static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
+{
+ struct net *net = sock_net(skb->sk);
+ struct ifaddrlblmsg *ifal;
+ struct nlattr *tb[IFAL_MAX+1];
+ struct in6_addr *pfx;
+ u32 label;
+ int err = 0;
+
+ err = nlmsg_parse_deprecated(nlh, sizeof(*ifal), tb, IFAL_MAX,
+ ifal_policy, extack);
+ if (err < 0)
+ return err;
+
+ ifal = nlmsg_data(nlh);
+
+ if (ifal->ifal_family != AF_INET6 ||
+ ifal->ifal_prefixlen > 128)
+ return -EINVAL;
+
+ if (!tb[IFAL_ADDRESS])
+ return -EINVAL;
+ pfx = nla_data(tb[IFAL_ADDRESS]);
+
+ if (!tb[IFAL_LABEL])
+ return -EINVAL;
+ label = nla_get_u32(tb[IFAL_LABEL]);
+ if (label == IPV6_ADDR_LABEL_DEFAULT)
+ return -EINVAL;
+
+ switch (nlh->nlmsg_type) {
+ case RTM_NEWADDRLABEL:
+ if (ifal->ifal_index &&
+ !addrlbl_ifindex_exists(net, ifal->ifal_index))
+ return -EINVAL;
+
+ err = ip6addrlbl_add(net, pfx, ifal->ifal_prefixlen,
+ ifal->ifal_index, label,
+ nlh->nlmsg_flags & NLM_F_REPLACE);
+ break;
+ case RTM_DELADDRLABEL:
+ err = ip6addrlbl_del(net, pfx, ifal->ifal_prefixlen,
+ ifal->ifal_index);
+ break;
+ default:
+ err = -EOPNOTSUPP;
+ }
+ return err;
+}
+
+static void ip6addrlbl_putmsg(struct nlmsghdr *nlh,
+ int prefixlen, int ifindex, u32 lseq)
+{
+ struct ifaddrlblmsg *ifal = nlmsg_data(nlh);
+ ifal->ifal_family = AF_INET6;
+ ifal->__ifal_reserved = 0;
+ ifal->ifal_prefixlen = prefixlen;
+ ifal->ifal_flags = 0;
+ ifal->ifal_index = ifindex;
+ ifal->ifal_seq = lseq;
+};
+
+static int ip6addrlbl_fill(struct sk_buff *skb,
+ struct ip6addrlbl_entry *p,
+ u32 lseq,
+ u32 portid, u32 seq, int event,
+ unsigned int flags)
+{
+ struct nlmsghdr *nlh = nlmsg_put(skb, portid, seq, event,
+ sizeof(struct ifaddrlblmsg), flags);
+ if (!nlh)
+ return -EMSGSIZE;
+
+ ip6addrlbl_putmsg(nlh, p->prefixlen, p->ifindex, lseq);
+
+ if (nla_put_in6_addr(skb, IFAL_ADDRESS, &p->prefix) < 0 ||
+ nla_put_u32(skb, IFAL_LABEL, p->label) < 0) {
+ nlmsg_cancel(skb, nlh);
+ return -EMSGSIZE;
+ }
+
+ nlmsg_end(skb, nlh);
+ return 0;
+}
+
+static int ip6addrlbl_valid_dump_req(const struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
+{
+ struct ifaddrlblmsg *ifal;
+
+ if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifal))) {
+ NL_SET_ERR_MSG_MOD(extack, "Invalid header for address label dump request");
+ return -EINVAL;
+ }
+
+ ifal = nlmsg_data(nlh);
+ if (ifal->__ifal_reserved || ifal->ifal_prefixlen ||
+ ifal->ifal_flags || ifal->ifal_index || ifal->ifal_seq) {
+ NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address label dump request");
+ return -EINVAL;
+ }
+
+ if (nlmsg_attrlen(nlh, sizeof(*ifal))) {
+ NL_SET_ERR_MSG_MOD(extack, "Invalid data after header for address label dump request");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int ip6addrlbl_dump(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ const struct nlmsghdr *nlh = cb->nlh;
+ struct net *net = sock_net(skb->sk);
+ struct ip6addrlbl_entry *p;
+ int idx = 0, s_idx = cb->args[0];
+ int err;
+
+ if (cb->strict_check) {
+ err = ip6addrlbl_valid_dump_req(nlh, cb->extack);
+ if (err < 0)
+ return err;
+ }
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(p, &net->ipv6.ip6addrlbl_table.head, list) {
+ if (idx >= s_idx) {
+ err = ip6addrlbl_fill(skb, p,
+ net->ipv6.ip6addrlbl_table.seq,
+ NETLINK_CB(cb->skb).portid,
+ nlh->nlmsg_seq,
+ RTM_NEWADDRLABEL,
+ NLM_F_MULTI);
+ if (err < 0)
+ break;
+ }
+ idx++;
+ }
+ rcu_read_unlock();
+ cb->args[0] = idx;
+ return skb->len;
+}
+
+static inline int ip6addrlbl_msgsize(void)
+{
+ return NLMSG_ALIGN(sizeof(struct ifaddrlblmsg))
+ + nla_total_size(16) /* IFAL_ADDRESS */
+ + nla_total_size(4); /* IFAL_LABEL */
+}
+
+static int ip6addrlbl_valid_get_req(struct sk_buff *skb,
+ const struct nlmsghdr *nlh,
+ struct nlattr **tb,
+ struct netlink_ext_ack *extack)
+{
+ struct ifaddrlblmsg *ifal;
+ int i, err;
+
+ if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifal))) {
+ NL_SET_ERR_MSG_MOD(extack, "Invalid header for addrlabel get request");
+ return -EINVAL;
+ }
+
+ if (!netlink_strict_get_check(skb))
+ return nlmsg_parse_deprecated(nlh, sizeof(*ifal), tb,
+ IFAL_MAX, ifal_policy, extack);
+
+ ifal = nlmsg_data(nlh);
+ if (ifal->__ifal_reserved || ifal->ifal_flags || ifal->ifal_seq) {
+ NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for addrlabel get request");
+ return -EINVAL;
+ }
+
+ err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifal), tb, IFAL_MAX,
+ ifal_policy, extack);
+ if (err)
+ return err;
+
+ for (i = 0; i <= IFAL_MAX; i++) {
+ if (!tb[i])
+ continue;
+
+ switch (i) {
+ case IFAL_ADDRESS:
+ break;
+ default:
+ NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in addrlabel get request");
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
+static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
+{
+ struct net *net = sock_net(in_skb->sk);
+ struct ifaddrlblmsg *ifal;
+ struct nlattr *tb[IFAL_MAX+1];
+ struct in6_addr *addr;
+ u32 lseq;
+ int err = 0;
+ struct ip6addrlbl_entry *p;
+ struct sk_buff *skb;
+
+ err = ip6addrlbl_valid_get_req(in_skb, nlh, tb, extack);
+ if (err < 0)
+ return err;
+
+ ifal = nlmsg_data(nlh);
+
+ if (ifal->ifal_family != AF_INET6 ||
+ ifal->ifal_prefixlen != 128)
+ return -EINVAL;
+
+ if (ifal->ifal_index &&
+ !addrlbl_ifindex_exists(net, ifal->ifal_index))
+ return -EINVAL;
+
+ if (!tb[IFAL_ADDRESS])
+ return -EINVAL;
+ addr = nla_data(tb[IFAL_ADDRESS]);
+
+ skb = nlmsg_new(ip6addrlbl_msgsize(), GFP_KERNEL);
+ if (!skb)
+ return -ENOBUFS;
+
+ err = -ESRCH;
+
+ rcu_read_lock();
+ p = __ipv6_addr_label(net, addr, ipv6_addr_type(addr), ifal->ifal_index);
+ lseq = net->ipv6.ip6addrlbl_table.seq;
+ if (p)
+ err = ip6addrlbl_fill(skb, p, lseq,
+ NETLINK_CB(in_skb).portid,
+ nlh->nlmsg_seq,
+ RTM_NEWADDRLABEL, 0);
+ rcu_read_unlock();
+
+ if (err < 0) {
+ WARN_ON(err == -EMSGSIZE);
+ kfree_skb(skb);
+ } else {
+ err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
+ }
+ return err;
+}
+
+int __init ipv6_addr_label_rtnl_register(void)
+{
+ int ret;
+
+ ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDRLABEL,
+ ip6addrlbl_newdel,
+ NULL, RTNL_FLAG_DOIT_UNLOCKED);
+ if (ret < 0)
+ return ret;
+ ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDRLABEL,
+ ip6addrlbl_newdel,
+ NULL, RTNL_FLAG_DOIT_UNLOCKED);
+ if (ret < 0)
+ return ret;
+ ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDRLABEL,
+ ip6addrlbl_get,
+ ip6addrlbl_dump, RTNL_FLAG_DOIT_UNLOCKED);
+ return ret;
+}
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