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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /net/ipv6/seg6.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'net/ipv6/seg6.c')
-rw-r--r--net/ipv6/seg6.c569
1 files changed, 569 insertions, 0 deletions
diff --git a/net/ipv6/seg6.c b/net/ipv6/seg6.c
new file mode 100644
index 000000000..29346a6ee
--- /dev/null
+++ b/net/ipv6/seg6.c
@@ -0,0 +1,569 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * SR-IPv6 implementation
+ *
+ * Author:
+ * David Lebrun <david.lebrun@uclouvain.be>
+ */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/net.h>
+#include <linux/in6.h>
+#include <linux/slab.h>
+#include <linux/rhashtable.h>
+
+#include <net/ipv6.h>
+#include <net/protocol.h>
+
+#include <net/seg6.h>
+#include <net/genetlink.h>
+#include <linux/seg6.h>
+#include <linux/seg6_genl.h>
+#ifdef CONFIG_IPV6_SEG6_HMAC
+#include <net/seg6_hmac.h>
+#endif
+
+bool seg6_validate_srh(struct ipv6_sr_hdr *srh, int len, bool reduced)
+{
+ unsigned int tlv_offset;
+ int max_last_entry;
+ int trailing;
+
+ if (srh->type != IPV6_SRCRT_TYPE_4)
+ return false;
+
+ if (((srh->hdrlen + 1) << 3) != len)
+ return false;
+
+ if (!reduced && srh->segments_left > srh->first_segment) {
+ return false;
+ } else {
+ max_last_entry = (srh->hdrlen / 2) - 1;
+
+ if (srh->first_segment > max_last_entry)
+ return false;
+
+ if (srh->segments_left > srh->first_segment + 1)
+ return false;
+ }
+
+ tlv_offset = sizeof(*srh) + ((srh->first_segment + 1) << 4);
+
+ trailing = len - tlv_offset;
+ if (trailing < 0)
+ return false;
+
+ while (trailing) {
+ struct sr6_tlv *tlv;
+ unsigned int tlv_len;
+
+ if (trailing < sizeof(*tlv))
+ return false;
+
+ tlv = (struct sr6_tlv *)((unsigned char *)srh + tlv_offset);
+ tlv_len = sizeof(*tlv) + tlv->len;
+
+ trailing -= tlv_len;
+ if (trailing < 0)
+ return false;
+
+ tlv_offset += tlv_len;
+ }
+
+ return true;
+}
+
+struct ipv6_sr_hdr *seg6_get_srh(struct sk_buff *skb, int flags)
+{
+ struct ipv6_sr_hdr *srh;
+ int len, srhoff = 0;
+
+ if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, &flags) < 0)
+ return NULL;
+
+ if (!pskb_may_pull(skb, srhoff + sizeof(*srh)))
+ return NULL;
+
+ srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
+
+ len = (srh->hdrlen + 1) << 3;
+
+ if (!pskb_may_pull(skb, srhoff + len))
+ return NULL;
+
+ /* note that pskb_may_pull may change pointers in header;
+ * for this reason it is necessary to reload them when needed.
+ */
+ srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
+
+ if (!seg6_validate_srh(srh, len, true))
+ return NULL;
+
+ return srh;
+}
+
+/* Determine if an ICMP invoking packet contains a segment routing
+ * header. If it does, extract the offset to the true destination
+ * address, which is in the first segment address.
+ */
+void seg6_icmp_srh(struct sk_buff *skb, struct inet6_skb_parm *opt)
+{
+ __u16 network_header = skb->network_header;
+ struct ipv6_sr_hdr *srh;
+
+ /* Update network header to point to the invoking packet
+ * inside the ICMP packet, so we can use the seg6_get_srh()
+ * helper.
+ */
+ skb_reset_network_header(skb);
+
+ srh = seg6_get_srh(skb, 0);
+ if (!srh)
+ goto out;
+
+ if (srh->type != IPV6_SRCRT_TYPE_4)
+ goto out;
+
+ opt->flags |= IP6SKB_SEG6;
+ opt->srhoff = (unsigned char *)srh - skb->data;
+
+out:
+ /* Restore the network header back to the ICMP packet */
+ skb->network_header = network_header;
+}
+
+static struct genl_family seg6_genl_family;
+
+static const struct nla_policy seg6_genl_policy[SEG6_ATTR_MAX + 1] = {
+ [SEG6_ATTR_DST] = { .type = NLA_BINARY,
+ .len = sizeof(struct in6_addr) },
+ [SEG6_ATTR_DSTLEN] = { .type = NLA_S32, },
+ [SEG6_ATTR_HMACKEYID] = { .type = NLA_U32, },
+ [SEG6_ATTR_SECRET] = { .type = NLA_BINARY, },
+ [SEG6_ATTR_SECRETLEN] = { .type = NLA_U8, },
+ [SEG6_ATTR_ALGID] = { .type = NLA_U8, },
+ [SEG6_ATTR_HMACINFO] = { .type = NLA_NESTED, },
+};
+
+#ifdef CONFIG_IPV6_SEG6_HMAC
+
+static int seg6_genl_sethmac(struct sk_buff *skb, struct genl_info *info)
+{
+ struct net *net = genl_info_net(info);
+ struct seg6_pernet_data *sdata;
+ struct seg6_hmac_info *hinfo;
+ u32 hmackeyid;
+ char *secret;
+ int err = 0;
+ u8 algid;
+ u8 slen;
+
+ sdata = seg6_pernet(net);
+
+ if (!info->attrs[SEG6_ATTR_HMACKEYID] ||
+ !info->attrs[SEG6_ATTR_SECRETLEN] ||
+ !info->attrs[SEG6_ATTR_ALGID])
+ return -EINVAL;
+
+ hmackeyid = nla_get_u32(info->attrs[SEG6_ATTR_HMACKEYID]);
+ slen = nla_get_u8(info->attrs[SEG6_ATTR_SECRETLEN]);
+ algid = nla_get_u8(info->attrs[SEG6_ATTR_ALGID]);
+
+ if (hmackeyid == 0)
+ return -EINVAL;
+
+ if (slen > SEG6_HMAC_SECRET_LEN)
+ return -EINVAL;
+
+ mutex_lock(&sdata->lock);
+ hinfo = seg6_hmac_info_lookup(net, hmackeyid);
+
+ if (!slen) {
+ err = seg6_hmac_info_del(net, hmackeyid);
+
+ goto out_unlock;
+ }
+
+ if (!info->attrs[SEG6_ATTR_SECRET]) {
+ err = -EINVAL;
+ goto out_unlock;
+ }
+
+ if (slen > nla_len(info->attrs[SEG6_ATTR_SECRET])) {
+ err = -EINVAL;
+ goto out_unlock;
+ }
+
+ if (hinfo) {
+ err = seg6_hmac_info_del(net, hmackeyid);
+ if (err)
+ goto out_unlock;
+ }
+
+ secret = (char *)nla_data(info->attrs[SEG6_ATTR_SECRET]);
+
+ hinfo = kzalloc(sizeof(*hinfo), GFP_KERNEL);
+ if (!hinfo) {
+ err = -ENOMEM;
+ goto out_unlock;
+ }
+
+ memcpy(hinfo->secret, secret, slen);
+ hinfo->slen = slen;
+ hinfo->alg_id = algid;
+ hinfo->hmackeyid = hmackeyid;
+
+ err = seg6_hmac_info_add(net, hmackeyid, hinfo);
+ if (err)
+ kfree(hinfo);
+
+out_unlock:
+ mutex_unlock(&sdata->lock);
+ return err;
+}
+
+#else
+
+static int seg6_genl_sethmac(struct sk_buff *skb, struct genl_info *info)
+{
+ return -ENOTSUPP;
+}
+
+#endif
+
+static int seg6_genl_set_tunsrc(struct sk_buff *skb, struct genl_info *info)
+{
+ struct net *net = genl_info_net(info);
+ struct in6_addr *val, *t_old, *t_new;
+ struct seg6_pernet_data *sdata;
+
+ sdata = seg6_pernet(net);
+
+ if (!info->attrs[SEG6_ATTR_DST])
+ return -EINVAL;
+
+ val = nla_data(info->attrs[SEG6_ATTR_DST]);
+ t_new = kmemdup(val, sizeof(*val), GFP_KERNEL);
+ if (!t_new)
+ return -ENOMEM;
+
+ mutex_lock(&sdata->lock);
+
+ t_old = sdata->tun_src;
+ rcu_assign_pointer(sdata->tun_src, t_new);
+
+ mutex_unlock(&sdata->lock);
+
+ synchronize_net();
+ kfree(t_old);
+
+ return 0;
+}
+
+static int seg6_genl_get_tunsrc(struct sk_buff *skb, struct genl_info *info)
+{
+ struct net *net = genl_info_net(info);
+ struct in6_addr *tun_src;
+ struct sk_buff *msg;
+ void *hdr;
+
+ msg = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
+
+ hdr = genlmsg_put(msg, info->snd_portid, info->snd_seq,
+ &seg6_genl_family, 0, SEG6_CMD_GET_TUNSRC);
+ if (!hdr)
+ goto free_msg;
+
+ rcu_read_lock();
+ tun_src = rcu_dereference(seg6_pernet(net)->tun_src);
+
+ if (nla_put(msg, SEG6_ATTR_DST, sizeof(struct in6_addr), tun_src))
+ goto nla_put_failure;
+
+ rcu_read_unlock();
+
+ genlmsg_end(msg, hdr);
+ return genlmsg_reply(msg, info);
+
+nla_put_failure:
+ rcu_read_unlock();
+free_msg:
+ nlmsg_free(msg);
+ return -ENOMEM;
+}
+
+#ifdef CONFIG_IPV6_SEG6_HMAC
+
+static int __seg6_hmac_fill_info(struct seg6_hmac_info *hinfo,
+ struct sk_buff *msg)
+{
+ if (nla_put_u32(msg, SEG6_ATTR_HMACKEYID, hinfo->hmackeyid) ||
+ nla_put_u8(msg, SEG6_ATTR_SECRETLEN, hinfo->slen) ||
+ nla_put(msg, SEG6_ATTR_SECRET, hinfo->slen, hinfo->secret) ||
+ nla_put_u8(msg, SEG6_ATTR_ALGID, hinfo->alg_id))
+ return -1;
+
+ return 0;
+}
+
+static int __seg6_genl_dumphmac_element(struct seg6_hmac_info *hinfo,
+ u32 portid, u32 seq, u32 flags,
+ struct sk_buff *skb, u8 cmd)
+{
+ void *hdr;
+
+ hdr = genlmsg_put(skb, portid, seq, &seg6_genl_family, flags, cmd);
+ if (!hdr)
+ return -ENOMEM;
+
+ if (__seg6_hmac_fill_info(hinfo, skb) < 0)
+ goto nla_put_failure;
+
+ genlmsg_end(skb, hdr);
+ return 0;
+
+nla_put_failure:
+ genlmsg_cancel(skb, hdr);
+ return -EMSGSIZE;
+}
+
+static int seg6_genl_dumphmac_start(struct netlink_callback *cb)
+{
+ struct net *net = sock_net(cb->skb->sk);
+ struct seg6_pernet_data *sdata;
+ struct rhashtable_iter *iter;
+
+ sdata = seg6_pernet(net);
+ iter = (struct rhashtable_iter *)cb->args[0];
+
+ if (!iter) {
+ iter = kmalloc(sizeof(*iter), GFP_KERNEL);
+ if (!iter)
+ return -ENOMEM;
+
+ cb->args[0] = (long)iter;
+ }
+
+ rhashtable_walk_enter(&sdata->hmac_infos, iter);
+
+ return 0;
+}
+
+static int seg6_genl_dumphmac_done(struct netlink_callback *cb)
+{
+ struct rhashtable_iter *iter = (struct rhashtable_iter *)cb->args[0];
+
+ rhashtable_walk_exit(iter);
+
+ kfree(iter);
+
+ return 0;
+}
+
+static int seg6_genl_dumphmac(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ struct rhashtable_iter *iter = (struct rhashtable_iter *)cb->args[0];
+ struct seg6_hmac_info *hinfo;
+ int ret;
+
+ rhashtable_walk_start(iter);
+
+ for (;;) {
+ hinfo = rhashtable_walk_next(iter);
+
+ if (IS_ERR(hinfo)) {
+ if (PTR_ERR(hinfo) == -EAGAIN)
+ continue;
+ ret = PTR_ERR(hinfo);
+ goto done;
+ } else if (!hinfo) {
+ break;
+ }
+
+ ret = __seg6_genl_dumphmac_element(hinfo,
+ NETLINK_CB(cb->skb).portid,
+ cb->nlh->nlmsg_seq,
+ NLM_F_MULTI,
+ skb, SEG6_CMD_DUMPHMAC);
+ if (ret)
+ goto done;
+ }
+
+ ret = skb->len;
+
+done:
+ rhashtable_walk_stop(iter);
+ return ret;
+}
+
+#else
+
+static int seg6_genl_dumphmac_start(struct netlink_callback *cb)
+{
+ return 0;
+}
+
+static int seg6_genl_dumphmac_done(struct netlink_callback *cb)
+{
+ return 0;
+}
+
+static int seg6_genl_dumphmac(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ return -ENOTSUPP;
+}
+
+#endif
+
+static int __net_init seg6_net_init(struct net *net)
+{
+ struct seg6_pernet_data *sdata;
+
+ sdata = kzalloc(sizeof(*sdata), GFP_KERNEL);
+ if (!sdata)
+ return -ENOMEM;
+
+ mutex_init(&sdata->lock);
+
+ sdata->tun_src = kzalloc(sizeof(*sdata->tun_src), GFP_KERNEL);
+ if (!sdata->tun_src) {
+ kfree(sdata);
+ return -ENOMEM;
+ }
+
+ net->ipv6.seg6_data = sdata;
+
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ if (seg6_hmac_net_init(net)) {
+ kfree(rcu_dereference_raw(sdata->tun_src));
+ kfree(sdata);
+ return -ENOMEM;
+ }
+#endif
+
+ return 0;
+}
+
+static void __net_exit seg6_net_exit(struct net *net)
+{
+ struct seg6_pernet_data *sdata = seg6_pernet(net);
+
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ seg6_hmac_net_exit(net);
+#endif
+
+ kfree(rcu_dereference_raw(sdata->tun_src));
+ kfree(sdata);
+}
+
+static struct pernet_operations ip6_segments_ops = {
+ .init = seg6_net_init,
+ .exit = seg6_net_exit,
+};
+
+static const struct genl_ops seg6_genl_ops[] = {
+ {
+ .cmd = SEG6_CMD_SETHMAC,
+ .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
+ .doit = seg6_genl_sethmac,
+ .flags = GENL_ADMIN_PERM,
+ },
+ {
+ .cmd = SEG6_CMD_DUMPHMAC,
+ .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
+ .start = seg6_genl_dumphmac_start,
+ .dumpit = seg6_genl_dumphmac,
+ .done = seg6_genl_dumphmac_done,
+ .flags = GENL_ADMIN_PERM,
+ },
+ {
+ .cmd = SEG6_CMD_SET_TUNSRC,
+ .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
+ .doit = seg6_genl_set_tunsrc,
+ .flags = GENL_ADMIN_PERM,
+ },
+ {
+ .cmd = SEG6_CMD_GET_TUNSRC,
+ .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
+ .doit = seg6_genl_get_tunsrc,
+ .flags = GENL_ADMIN_PERM,
+ },
+};
+
+static struct genl_family seg6_genl_family __ro_after_init = {
+ .hdrsize = 0,
+ .name = SEG6_GENL_NAME,
+ .version = SEG6_GENL_VERSION,
+ .maxattr = SEG6_ATTR_MAX,
+ .policy = seg6_genl_policy,
+ .netnsok = true,
+ .parallel_ops = true,
+ .ops = seg6_genl_ops,
+ .n_ops = ARRAY_SIZE(seg6_genl_ops),
+ .resv_start_op = SEG6_CMD_GET_TUNSRC + 1,
+ .module = THIS_MODULE,
+};
+
+int __init seg6_init(void)
+{
+ int err;
+
+ err = genl_register_family(&seg6_genl_family);
+ if (err)
+ goto out;
+
+ err = register_pernet_subsys(&ip6_segments_ops);
+ if (err)
+ goto out_unregister_genl;
+
+#ifdef CONFIG_IPV6_SEG6_LWTUNNEL
+ err = seg6_iptunnel_init();
+ if (err)
+ goto out_unregister_pernet;
+
+ err = seg6_local_init();
+ if (err)
+ goto out_unregister_pernet;
+#endif
+
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ err = seg6_hmac_init();
+ if (err)
+ goto out_unregister_iptun;
+#endif
+
+ pr_info("Segment Routing with IPv6\n");
+
+out:
+ return err;
+#ifdef CONFIG_IPV6_SEG6_HMAC
+out_unregister_iptun:
+#ifdef CONFIG_IPV6_SEG6_LWTUNNEL
+ seg6_local_exit();
+ seg6_iptunnel_exit();
+#endif
+#endif
+#ifdef CONFIG_IPV6_SEG6_LWTUNNEL
+out_unregister_pernet:
+ unregister_pernet_subsys(&ip6_segments_ops);
+#endif
+out_unregister_genl:
+ genl_unregister_family(&seg6_genl_family);
+ goto out;
+}
+
+void seg6_exit(void)
+{
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ seg6_hmac_exit();
+#endif
+#ifdef CONFIG_IPV6_SEG6_LWTUNNEL
+ seg6_iptunnel_exit();
+#endif
+ unregister_pernet_subsys(&ip6_segments_ops);
+ genl_unregister_family(&seg6_genl_family);
+}