--- /dev/null
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/socket.h>
+#include <linux/skbuff.h>
+#include <linux/ip.h>
+#include <linux/udp.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <net/genetlink.h>
+#include <net/gue.h>
+#include <net/ip.h>
+#include <net/protocol.h>
+#include <net/udp.h>
+#include <net/udp_tunnel.h>
+#include <net/xfrm.h>
+#include <uapi/linux/fou.h>
+#include <uapi/linux/genetlink.h>
+
+struct fou {
+ struct socket *sock;
+ u8 protocol;
+ u8 flags;
+ __be16 port;
+ u16 type;
+ struct udp_offload udp_offloads;
+ struct list_head list;
+};
+
+#define FOU_F_REMCSUM_NOPARTIAL BIT(0)
+
+struct fou_cfg {
+ u16 type;
+ u8 protocol;
+ u8 flags;
+ struct udp_port_cfg udp_config;
+};
+
+static unsigned int fou_net_id;
+
+struct fou_net {
+ struct list_head fou_list;
+ struct mutex fou_lock;
+};
+
+static inline struct fou *fou_from_sock(struct sock *sk)
+{
+ return sk->sk_user_data;
+}
+
+static void fou_recv_pull(struct sk_buff *skb, size_t len)
+{
+ struct iphdr *iph = ip_hdr(skb);
+
+ /* Remove 'len' bytes from the packet (UDP header and
+ * FOU header if present).
+ */
+ iph->tot_len = htons(ntohs(iph->tot_len) - len);
+ __skb_pull(skb, len);
+ skb_postpull_rcsum(skb, udp_hdr(skb), len);
+ skb_reset_transport_header(skb);
+}
+
+static int fou_udp_recv(struct sock *sk, struct sk_buff *skb)
+{
+ struct fou *fou = fou_from_sock(sk);
+
+ if (!fou)
+ return 1;
+
+ fou_recv_pull(skb, sizeof(struct udphdr));
+
+ return -fou->protocol;
+}
+
+static struct guehdr *gue_remcsum(struct sk_buff *skb, struct guehdr *guehdr,
+ void *data, size_t hdrlen, u8 ipproto,
+ bool nopartial)
+{
+ __be16 *pd = data;
+ size_t start = ntohs(pd[0]);
+ size_t offset = ntohs(pd[1]);
+ size_t plen = hdrlen + max_t(size_t, offset + sizeof(u16), start);
+
+ if (!pskb_may_pull(skb, plen))
+ return NULL;
+ guehdr = (struct guehdr *)&udp_hdr(skb)[1];
+
+ skb_remcsum_process(skb, (void *)guehdr + hdrlen,
+ start, offset, nopartial);
+
+ return guehdr;
+}
+
+static int gue_control_message(struct sk_buff *skb, struct guehdr *guehdr)
+{
+ /* No support yet */
+ kfree_skb(skb);
+ return 0;
+}
+
+static int gue_udp_recv(struct sock *sk, struct sk_buff *skb)
+{
+ struct fou *fou = fou_from_sock(sk);
+ size_t len, optlen, hdrlen;
+ struct guehdr *guehdr;
+ void *data;
+ u16 doffset = 0;
+
+ if (!fou)
+ return 1;
+
+ len = sizeof(struct udphdr) + sizeof(struct guehdr);
+ if (!pskb_may_pull(skb, len))
+ goto drop;
+
+ guehdr = (struct guehdr *)&udp_hdr(skb)[1];
+
+ optlen = guehdr->hlen << 2;
+ len += optlen;
+
+ if (!pskb_may_pull(skb, len))
+ goto drop;
+
+ /* guehdr may change after pull */
+ guehdr = (struct guehdr *)&udp_hdr(skb)[1];
+
+ hdrlen = sizeof(struct guehdr) + optlen;
+
+ if (guehdr->version != 0 || validate_gue_flags(guehdr, optlen))
+ goto drop;
+
+ hdrlen = sizeof(struct guehdr) + optlen;
+
+ ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(skb)->tot_len) - len);
+
+ /* Pull csum through the guehdr now . This can be used if
+ * there is a remote checksum offload.
+ */
+ skb_postpull_rcsum(skb, udp_hdr(skb), len);
+
+ data = &guehdr[1];
+
+ if (guehdr->flags & GUE_FLAG_PRIV) {
+ __be32 flags = *(__be32 *)(data + doffset);
+
+ doffset += GUE_LEN_PRIV;
+
+ if (flags & GUE_PFLAG_REMCSUM) {
+ guehdr = gue_remcsum(skb, guehdr, data + doffset,
+ hdrlen, guehdr->proto_ctype,
+ !!(fou->flags &
+ FOU_F_REMCSUM_NOPARTIAL));
+ if (!guehdr)
+ goto drop;
+
+ data = &guehdr[1];
+
+ doffset += GUE_PLEN_REMCSUM;
+ }
+ }
+
+ if (unlikely(guehdr->control))
+ return gue_control_message(skb, guehdr);
+
+ __skb_pull(skb, sizeof(struct udphdr) + hdrlen);
+ skb_reset_transport_header(skb);
+
+ return -guehdr->proto_ctype;
+
+drop:
+ kfree_skb(skb);
+ return 0;
+}
+
+static struct sk_buff **fou_gro_receive(struct sk_buff **head,
+ struct sk_buff *skb,
+ struct udp_offload *uoff)
+{
+ const struct net_offload *ops;
+ struct sk_buff **pp = NULL;
+ u8 proto = NAPI_GRO_CB(skb)->proto;
+ const struct net_offload **offloads;
+
+ rcu_read_lock();
+ offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
+ ops = rcu_dereference(offloads[proto]);
+ if (!ops || !ops->callbacks.gro_receive)
+ goto out_unlock;
+
+ pp = ops->callbacks.gro_receive(head, skb);
+
+out_unlock:
+ rcu_read_unlock();
+
+ return pp;
+}
+
+static int fou_gro_complete(struct sk_buff *skb, int nhoff,
+ struct udp_offload *uoff)
+{
+ const struct net_offload *ops;
+ u8 proto = NAPI_GRO_CB(skb)->proto;
+ int err = -ENOSYS;
+ const struct net_offload **offloads;
+
+ udp_tunnel_gro_complete(skb, nhoff);
+
+ rcu_read_lock();
+ offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
+ ops = rcu_dereference(offloads[proto]);
+ if (WARN_ON(!ops || !ops->callbacks.gro_complete))
+ goto out_unlock;
+
+ err = ops->callbacks.gro_complete(skb, nhoff);
+
+out_unlock:
+ rcu_read_unlock();
+
+ return err;
+}
+
+static struct guehdr *gue_gro_remcsum(struct sk_buff *skb, unsigned int off,
+ struct guehdr *guehdr, void *data,
+ size_t hdrlen, u8 ipproto,
+ struct gro_remcsum *grc, bool nopartial)
+{
+ __be16 *pd = data;
+ size_t start = ntohs(pd[0]);
+ size_t offset = ntohs(pd[1]);
+ size_t plen = hdrlen + max_t(size_t, offset + sizeof(u16), start);
+
+ if (skb->remcsum_offload)
+ return NULL;
+
+ if (!NAPI_GRO_CB(skb)->csum_valid)
+ return NULL;
+
+ /* Pull checksum that will be written */
+ if (skb_gro_header_hard(skb, off + plen)) {
+ guehdr = skb_gro_header_slow(skb, off + plen, off);
+ if (!guehdr)
+ return NULL;
+ }
+
+ skb_gro_remcsum_process(skb, (void *)guehdr + hdrlen,
+ start, offset, grc, nopartial);
+
+ skb->remcsum_offload = 1;
+
+ return guehdr;
+}
+
+static struct sk_buff **gue_gro_receive(struct sk_buff **head,
+ struct sk_buff *skb,
+ struct udp_offload *uoff)
+{
+ const struct net_offload **offloads;
+ const struct net_offload *ops;
+ struct sk_buff **pp = NULL;
+ struct sk_buff *p;
+ struct guehdr *guehdr;
+ size_t len, optlen, hdrlen, off;
+ void *data;
+ u16 doffset = 0;
+ int flush = 1;
+ struct fou *fou = container_of(uoff, struct fou, udp_offloads);
+ struct gro_remcsum grc;
+
+ skb_gro_remcsum_init(&grc);
+
+ off = skb_gro_offset(skb);
+ len = off + sizeof(*guehdr);
+
+ guehdr = skb_gro_header_fast(skb, off);
+ if (skb_gro_header_hard(skb, len)) {
+ guehdr = skb_gro_header_slow(skb, len, off);
+ if (unlikely(!guehdr))
+ goto out;
+ }
+
+ optlen = guehdr->hlen << 2;
+ len += optlen;
+
+ if (skb_gro_header_hard(skb, len)) {
+ guehdr = skb_gro_header_slow(skb, len, off);
+ if (unlikely(!guehdr))
+ goto out;
+ }
+
+ if (unlikely(guehdr->control) || guehdr->version != 0 ||
+ validate_gue_flags(guehdr, optlen))
+ goto out;
+
+ hdrlen = sizeof(*guehdr) + optlen;
+
+ /* Adjust NAPI_GRO_CB(skb)->csum to account for guehdr,
+ * this is needed if there is a remote checkcsum offload.
+ */
+ skb_gro_postpull_rcsum(skb, guehdr, hdrlen);
+
+ data = &guehdr[1];
+
+ if (guehdr->flags & GUE_FLAG_PRIV) {
+ __be32 flags = *(__be32 *)(data + doffset);
+
+ doffset += GUE_LEN_PRIV;
+
+ if (flags & GUE_PFLAG_REMCSUM) {
+ guehdr = gue_gro_remcsum(skb, off, guehdr,
+ data + doffset, hdrlen,
+ guehdr->proto_ctype, &grc,
+ !!(fou->flags &
+ FOU_F_REMCSUM_NOPARTIAL));
+ if (!guehdr)
+ goto out;
+
+ data = &guehdr[1];
+
+ doffset += GUE_PLEN_REMCSUM;
+ }
+ }
+
+ skb_gro_pull(skb, hdrlen);
+
+ flush = 0;
+
+ for (p = *head; p; p = p->next) {
+ const struct guehdr *guehdr2;
+
+ if (!NAPI_GRO_CB(p)->same_flow)
+ continue;
+
+ guehdr2 = (struct guehdr *)(p->data + off);
+
+ /* Compare base GUE header to be equal (covers
+ * hlen, version, proto_ctype, and flags.
+ */
+ if (guehdr->word != guehdr2->word) {
+ NAPI_GRO_CB(p)->same_flow = 0;
+ continue;
+ }
+
+ /* Compare optional fields are the same. */
+ if (guehdr->hlen && memcmp(&guehdr[1], &guehdr2[1],
+ guehdr->hlen << 2)) {
+ NAPI_GRO_CB(p)->same_flow = 0;
+ continue;
+ }
+ }
+
+ rcu_read_lock();
+ offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
+ ops = rcu_dereference(offloads[guehdr->proto_ctype]);
+ if (WARN_ON(!ops || !ops->callbacks.gro_receive))
+ goto out_unlock;
+
+ pp = ops->callbacks.gro_receive(head, skb);
+
+out_unlock:
+ rcu_read_unlock();
+out:
+ NAPI_GRO_CB(skb)->flush |= flush;
+ skb_gro_remcsum_cleanup(skb, &grc);
+
+ return pp;
+}
+
+static int gue_gro_complete(struct sk_buff *skb, int nhoff,
+ struct udp_offload *uoff)
+{
+ const struct net_offload **offloads;
+ struct guehdr *guehdr = (struct guehdr *)(skb->data + nhoff);
+ const struct net_offload *ops;
+ unsigned int guehlen;
+ u8 proto;
+ int err = -ENOENT;
+
+ proto = guehdr->proto_ctype;
+
+ guehlen = sizeof(*guehdr) + (guehdr->hlen << 2);
+
+ rcu_read_lock();
+ offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
+ ops = rcu_dereference(offloads[proto]);
+ if (WARN_ON(!ops || !ops->callbacks.gro_complete))
+ goto out_unlock;
+
+ err = ops->callbacks.gro_complete(skb, nhoff + guehlen);
+
+out_unlock:
+ rcu_read_unlock();
+ return err;
+}
+
+static int fou_add_to_port_list(struct net *net, struct fou *fou)
+{
+ struct fou_net *fn = net_generic(net, fou_net_id);
+ struct fou *fout;
+
+ mutex_lock(&fn->fou_lock);
+ list_for_each_entry(fout, &fn->fou_list, list) {
+ if (fou->port == fout->port) {
+ mutex_unlock(&fn->fou_lock);
+ return -EALREADY;
+ }
+ }
+
+ list_add(&fou->list, &fn->fou_list);
+ mutex_unlock(&fn->fou_lock);
+
+ return 0;
+}
+
+static void fou_release(struct fou *fou)
+{
+ struct socket *sock = fou->sock;
+ struct sock *sk = sock->sk;
+
+ if (sk->sk_family == AF_INET)
+ udp_del_offload(&fou->udp_offloads);
+ list_del(&fou->list);
+ udp_tunnel_sock_release(sock);
+
+ kfree(fou);
+}
+
+static int fou_encap_init(struct sock *sk, struct fou *fou, struct fou_cfg *cfg)
+{
+ udp_sk(sk)->encap_rcv = fou_udp_recv;
+ fou->protocol = cfg->protocol;
+ fou->udp_offloads.callbacks.gro_receive = fou_gro_receive;
+ fou->udp_offloads.callbacks.gro_complete = fou_gro_complete;
+ fou->udp_offloads.port = cfg->udp_config.local_udp_port;
+ fou->udp_offloads.ipproto = cfg->protocol;
+
+ return 0;
+}
+
+static int gue_encap_init(struct sock *sk, struct fou *fou, struct fou_cfg *cfg)
+{
+ udp_sk(sk)->encap_rcv = gue_udp_recv;
+ fou->udp_offloads.callbacks.gro_receive = gue_gro_receive;
+ fou->udp_offloads.callbacks.gro_complete = gue_gro_complete;
+ fou->udp_offloads.port = cfg->udp_config.local_udp_port;
+
+ return 0;
+}
+
+static int fou_create(struct net *net, struct fou_cfg *cfg,
+ struct socket **sockp)
+{
+ struct socket *sock = NULL;
+ struct fou *fou = NULL;
+ struct sock *sk;
+ int err;
+
+ /* Open UDP socket */
+ err = udp_sock_create(net, &cfg->udp_config, &sock);
+ if (err < 0)
+ goto error;
+
+ /* Allocate FOU port structure */
+ fou = kzalloc(sizeof(*fou), GFP_KERNEL);
+ if (!fou) {
+ err = -ENOMEM;
+ goto error;
+ }
+
+ sk = sock->sk;
+
+ fou->flags = cfg->flags;
+ fou->port = cfg->udp_config.local_udp_port;
+
+ /* Initial for fou type */
+ switch (cfg->type) {
+ case FOU_ENCAP_DIRECT:
+ err = fou_encap_init(sk, fou, cfg);
+ if (err)
+ goto error;
+ break;
+ case FOU_ENCAP_GUE:
+ err = gue_encap_init(sk, fou, cfg);
+ if (err)
+ goto error;
+ break;
+ default:
+ err = -EINVAL;
+ goto error;
+ }
+
+ fou->type = cfg->type;
+
+ udp_sk(sk)->encap_type = 1;
+ udp_encap_enable();
+
+ sk->sk_user_data = fou;
+ fou->sock = sock;
+
+ inet_inc_convert_csum(sk);
+
+ sk->sk_allocation = GFP_ATOMIC;
+
+ if (cfg->udp_config.family == AF_INET) {
+ err = udp_add_offload(&fou->udp_offloads);
+ if (err)
+ goto error;
+ }
+
+ err = fou_add_to_port_list(net, fou);
+ if (err)
+ goto error;
+
+ if (sockp)
+ *sockp = sock;
+
+ return 0;
+
+error:
+ kfree(fou);
+ if (sock)
+ udp_tunnel_sock_release(sock);
+
+ return err;
+}
+
+static int fou_destroy(struct net *net, struct fou_cfg *cfg)
+{
+ struct fou_net *fn = net_generic(net, fou_net_id);
+ __be16 port = cfg->udp_config.local_udp_port;
+ int err = -EINVAL;
+ struct fou *fou;
+
+ mutex_lock(&fn->fou_lock);
+ list_for_each_entry(fou, &fn->fou_list, list) {
+ if (fou->port == port) {
+ fou_release(fou);
+ err = 0;
+ break;
+ }
+ }
+ mutex_unlock(&fn->fou_lock);
+
+ return err;
+}
+
+static struct genl_family fou_nl_family = {
+ .id = GENL_ID_GENERATE,
+ .hdrsize = 0,
+ .name = FOU_GENL_NAME,
+ .version = FOU_GENL_VERSION,
+ .maxattr = FOU_ATTR_MAX,
+ .netnsok = true,
+};
+
+static struct nla_policy fou_nl_policy[FOU_ATTR_MAX + 1] = {
+ [FOU_ATTR_PORT] = { .type = NLA_U16, },
+ [FOU_ATTR_AF] = { .type = NLA_U8, },
+ [FOU_ATTR_IPPROTO] = { .type = NLA_U8, },
+ [FOU_ATTR_TYPE] = { .type = NLA_U8, },
+ [FOU_ATTR_REMCSUM_NOPARTIAL] = { .type = NLA_FLAG, },
+};
+
+static int parse_nl_config(struct genl_info *info,
+ struct fou_cfg *cfg)
+{
+ memset(cfg, 0, sizeof(*cfg));
+
+ cfg->udp_config.family = AF_INET;
+
+ if (info->attrs[FOU_ATTR_AF]) {
+ u8 family = nla_get_u8(info->attrs[FOU_ATTR_AF]);
+
+ if (family != AF_INET && family != AF_INET6)
+ return -EINVAL;
+
+ cfg->udp_config.family = family;
+ }
+
+ if (info->attrs[FOU_ATTR_PORT]) {
+ __be16 port = nla_get_be16(info->attrs[FOU_ATTR_PORT]);
+
+ cfg->udp_config.local_udp_port = port;
+ }
+
+ if (info->attrs[FOU_ATTR_IPPROTO])
+ cfg->protocol = nla_get_u8(info->attrs[FOU_ATTR_IPPROTO]);
+
+ if (info->attrs[FOU_ATTR_TYPE])
+ cfg->type = nla_get_u8(info->attrs[FOU_ATTR_TYPE]);
+
+ if (info->attrs[FOU_ATTR_REMCSUM_NOPARTIAL])
+ cfg->flags |= FOU_F_REMCSUM_NOPARTIAL;
+
+ return 0;
+}
+
+static int fou_nl_cmd_add_port(struct sk_buff *skb, struct genl_info *info)
+{
+ struct net *net = genl_info_net(info);
+ struct fou_cfg cfg;
+ int err;
+
+ err = parse_nl_config(info, &cfg);
+ if (err)
+ return err;
+
+ return fou_create(net, &cfg, NULL);
+}
+
+static int fou_nl_cmd_rm_port(struct sk_buff *skb, struct genl_info *info)
+{
+ struct net *net = genl_info_net(info);
+ struct fou_cfg cfg;
+ int err;
+
+ err = parse_nl_config(info, &cfg);
+ if (err)
+ return err;
+
+ return fou_destroy(net, &cfg);
+}
+
+static int fou_fill_info(struct fou *fou, struct sk_buff *msg)
+{
+ if (nla_put_u8(msg, FOU_ATTR_AF, fou->sock->sk->sk_family) ||
+ nla_put_be16(msg, FOU_ATTR_PORT, fou->port) ||
+ nla_put_u8(msg, FOU_ATTR_IPPROTO, fou->protocol) ||
+ nla_put_u8(msg, FOU_ATTR_TYPE, fou->type))
+ return -1;
+
+ if (fou->flags & FOU_F_REMCSUM_NOPARTIAL)
+ if (nla_put_flag(msg, FOU_ATTR_REMCSUM_NOPARTIAL))
+ return -1;
+ return 0;
+}
+
+static int fou_dump_info(struct fou *fou, u32 portid, u32 seq,
+ u32 flags, struct sk_buff *skb, u8 cmd)
+{
+ void *hdr;
+
+ hdr = genlmsg_put(skb, portid, seq, &fou_nl_family, flags, cmd);
+ if (!hdr)
+ return -ENOMEM;
+
+ if (fou_fill_info(fou, skb) < 0)
+ goto nla_put_failure;
+
+ genlmsg_end(skb, hdr);
+ return 0;
+
+nla_put_failure:
+ genlmsg_cancel(skb, hdr);
+ return -EMSGSIZE;
+}
+
+static int fou_nl_cmd_get_port(struct sk_buff *skb, struct genl_info *info)
+{
+ struct net *net = genl_info_net(info);
+ struct fou_net *fn = net_generic(net, fou_net_id);
+ struct sk_buff *msg;
+ struct fou_cfg cfg;
+ struct fou *fout;
+ __be16 port;
+ int ret;
+
+ ret = parse_nl_config(info, &cfg);
+ if (ret)
+ return ret;
+ port = cfg.udp_config.local_udp_port;
+ if (port == 0)
+ return -EINVAL;
+
+ msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
+
+ ret = -ESRCH;
+ mutex_lock(&fn->fou_lock);
+ list_for_each_entry(fout, &fn->fou_list, list) {
+ if (port == fout->port) {
+ ret = fou_dump_info(fout, info->snd_portid,
+ info->snd_seq, 0, msg,
+ info->genlhdr->cmd);
+ break;
+ }
+ }
+ mutex_unlock(&fn->fou_lock);
+ if (ret < 0)
+ goto out_free;
+
+ return genlmsg_reply(msg, info);
+
+out_free:
+ nlmsg_free(msg);
+ return ret;
+}
+
+static int fou_nl_dump(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ struct net *net = sock_net(skb->sk);
+ struct fou_net *fn = net_generic(net, fou_net_id);
+ struct fou *fout;
+ int idx = 0, ret;
+
+ mutex_lock(&fn->fou_lock);
+ list_for_each_entry(fout, &fn->fou_list, list) {
+ if (idx++ < cb->args[0])
+ continue;
+ ret = fou_dump_info(fout, NETLINK_CB(cb->skb).portid,
+ cb->nlh->nlmsg_seq, NLM_F_MULTI,
+ skb, FOU_CMD_GET);
+ if (ret)
+ break;
+ }
+ mutex_unlock(&fn->fou_lock);
+
+ cb->args[0] = idx;
+ return skb->len;
+}
+
+static const struct genl_ops fou_nl_ops[] = {
+ {
+ .cmd = FOU_CMD_ADD,
+ .doit = fou_nl_cmd_add_port,
+ .policy = fou_nl_policy,
+ .flags = GENL_ADMIN_PERM,
+ },
+ {
+ .cmd = FOU_CMD_DEL,
+ .doit = fou_nl_cmd_rm_port,
+ .policy = fou_nl_policy,
+ .flags = GENL_ADMIN_PERM,
+ },
+ {
+ .cmd = FOU_CMD_GET,
+ .doit = fou_nl_cmd_get_port,
+ .dumpit = fou_nl_dump,
+ .policy = fou_nl_policy,
+ },
+};
+
+size_t fou_encap_hlen(struct ip_tunnel_encap *e)
+{
+ return sizeof(struct udphdr);
+}
+EXPORT_SYMBOL(fou_encap_hlen);
+
+size_t gue_encap_hlen(struct ip_tunnel_encap *e)
+{
+ size_t len;
+ bool need_priv = false;
+
+ len = sizeof(struct udphdr) + sizeof(struct guehdr);
+
+ if (e->flags & TUNNEL_ENCAP_FLAG_REMCSUM) {
+ len += GUE_PLEN_REMCSUM;
+ need_priv = true;
+ }
+
+ len += need_priv ? GUE_LEN_PRIV : 0;
+
+ return len;
+}
+EXPORT_SYMBOL(gue_encap_hlen);
+
+static void fou_build_udp(struct sk_buff *skb, struct ip_tunnel_encap *e,
+ struct flowi4 *fl4, u8 *protocol, __be16 sport)
+{
+ struct udphdr *uh;
+
+ skb_push(skb, sizeof(struct udphdr));
+ skb_reset_transport_header(skb);
+
+ uh = udp_hdr(skb);
+
+ uh->dest = e->dport;
+ uh->source = sport;
+ uh->len = htons(skb->len);
+ uh->check = 0;
+ udp_set_csum(!(e->flags & TUNNEL_ENCAP_FLAG_CSUM), skb,
+ fl4->saddr, fl4->daddr, skb->len);
+
+ *protocol = IPPROTO_UDP;
+}
+
+int fou_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e,
+ u8 *protocol, struct flowi4 *fl4)
+{
+ bool csum = !!(e->flags & TUNNEL_ENCAP_FLAG_CSUM);
+ int type = csum ? SKB_GSO_UDP_TUNNEL_CSUM : SKB_GSO_UDP_TUNNEL;
+ __be16 sport;
+
+ skb = iptunnel_handle_offloads(skb, csum, type);
+
+ if (IS_ERR(skb))
+ return PTR_ERR(skb);
+
+ sport = e->sport ? : udp_flow_src_port(dev_net(skb->dev),
+ skb, 0, 0, false);
+ fou_build_udp(skb, e, fl4, protocol, sport);
+
+ return 0;
+}
+EXPORT_SYMBOL(fou_build_header);
+
+int gue_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e,
+ u8 *protocol, struct flowi4 *fl4)
+{
+ bool csum = !!(e->flags & TUNNEL_ENCAP_FLAG_CSUM);
+ int type = csum ? SKB_GSO_UDP_TUNNEL_CSUM : SKB_GSO_UDP_TUNNEL;
+ struct guehdr *guehdr;
+ size_t hdrlen, optlen = 0;
+ __be16 sport;
+ void *data;
+ bool need_priv = false;
+
+ if ((e->flags & TUNNEL_ENCAP_FLAG_REMCSUM) &&
+ skb->ip_summed == CHECKSUM_PARTIAL) {
+ csum = false;
+ optlen += GUE_PLEN_REMCSUM;
+ type |= SKB_GSO_TUNNEL_REMCSUM;
+ need_priv = true;
+ }
+
+ optlen += need_priv ? GUE_LEN_PRIV : 0;
+
+ skb = iptunnel_handle_offloads(skb, csum, type);
+
+ if (IS_ERR(skb))
+ return PTR_ERR(skb);
+
+ /* Get source port (based on flow hash) before skb_push */
+ sport = e->sport ? : udp_flow_src_port(dev_net(skb->dev),
+ skb, 0, 0, false);
+
+ hdrlen = sizeof(struct guehdr) + optlen;
+
+ skb_push(skb, hdrlen);
+
+ guehdr = (struct guehdr *)skb->data;
+
+ guehdr->control = 0;
+ guehdr->version = 0;
+ guehdr->hlen = optlen >> 2;
+ guehdr->flags = 0;
+ guehdr->proto_ctype = *protocol;
+
+ data = &guehdr[1];
+
+ if (need_priv) {
+ __be32 *flags = data;
+
+ guehdr->flags |= GUE_FLAG_PRIV;
+ *flags = 0;
+ data += GUE_LEN_PRIV;
+
+ if (type & SKB_GSO_TUNNEL_REMCSUM) {
+ u16 csum_start = skb_checksum_start_offset(skb);
+ __be16 *pd = data;
+
+ if (csum_start < hdrlen)
+ return -EINVAL;
+
+ csum_start -= hdrlen;
+ pd[0] = htons(csum_start);
+ pd[1] = htons(csum_start + skb->csum_offset);
+
+ if (!skb_is_gso(skb)) {
+ skb->ip_summed = CHECKSUM_NONE;
+ skb->encapsulation = 0;
+ }
+
+ *flags |= GUE_PFLAG_REMCSUM;
+ data += GUE_PLEN_REMCSUM;
+ }
+
+ }
+
+ fou_build_udp(skb, e, fl4, protocol, sport);
+
+ return 0;
+}
+EXPORT_SYMBOL(gue_build_header);
+
+#ifdef CONFIG_NET_FOU_IP_TUNNELS
+
+static const struct ip_tunnel_encap_ops fou_iptun_ops = {
+ .encap_hlen = fou_encap_hlen,
+ .build_header = fou_build_header,
+};
+
+static const struct ip_tunnel_encap_ops gue_iptun_ops = {
+ .encap_hlen = gue_encap_hlen,
+ .build_header = gue_build_header,
+};
+
+static int ip_tunnel_encap_add_fou_ops(void)
+{
+ int ret;
+
+ ret = ip_tunnel_encap_add_ops(&fou_iptun_ops, TUNNEL_ENCAP_FOU);
+ if (ret < 0) {
+ pr_err("can't add fou ops\n");
+ return ret;
+ }
+
+ ret = ip_tunnel_encap_add_ops(&gue_iptun_ops, TUNNEL_ENCAP_GUE);
+ if (ret < 0) {
+ pr_err("can't add gue ops\n");
+ ip_tunnel_encap_del_ops(&fou_iptun_ops, TUNNEL_ENCAP_FOU);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void ip_tunnel_encap_del_fou_ops(void)
+{
+ ip_tunnel_encap_del_ops(&fou_iptun_ops, TUNNEL_ENCAP_FOU);
+ ip_tunnel_encap_del_ops(&gue_iptun_ops, TUNNEL_ENCAP_GUE);
+}
+
+#else
+
+static int ip_tunnel_encap_add_fou_ops(void)
+{
+ return 0;
+}
+
+static void ip_tunnel_encap_del_fou_ops(void)
+{
+}
+
+#endif
+
+static __net_init int fou_init_net(struct net *net)
+{
+ struct fou_net *fn = net_generic(net, fou_net_id);
+
+ INIT_LIST_HEAD(&fn->fou_list);
+ mutex_init(&fn->fou_lock);
+ return 0;
+}
+
+static __net_exit void fou_exit_net(struct net *net)
+{
+ struct fou_net *fn = net_generic(net, fou_net_id);
+ struct fou *fou, *next;
+
+ /* Close all the FOU sockets */
+ mutex_lock(&fn->fou_lock);
+ list_for_each_entry_safe(fou, next, &fn->fou_list, list)
+ fou_release(fou);
+ mutex_unlock(&fn->fou_lock);
+}
+
+static struct pernet_operations fou_net_ops = {
+ .init = fou_init_net,
+ .exit = fou_exit_net,
+ .id = &fou_net_id,
+ .size = sizeof(struct fou_net),
+};
+
+static int __init fou_init(void)
+{
+ int ret;
+
+ ret = register_pernet_device(&fou_net_ops);
+ if (ret)
+ goto exit;
+
+ ret = genl_register_family_with_ops(&fou_nl_family,
+ fou_nl_ops);
+ if (ret < 0)
+ goto unregister;
+
+ ret = ip_tunnel_encap_add_fou_ops();
+ if (ret == 0)
+ return 0;
+
+ genl_unregister_family(&fou_nl_family);
+unregister:
+ unregister_pernet_device(&fou_net_ops);
+exit:
+ return ret;
+}
+
+static void __exit fou_fini(void)
+{
+ ip_tunnel_encap_del_fou_ops();
+ genl_unregister_family(&fou_nl_family);
+ unregister_pernet_device(&fou_net_ops);
+}
+
+module_init(fou_init);
+module_exit(fou_fini);
+MODULE_AUTHOR("Tom Herbert <therbert@google.com>");
+MODULE_LICENSE("GPL");
Code Review / kvmfornfv.git / blobdiff