const int code = icmp_hdr(icmp_skb)->code;
struct sock *sk;
struct sk_buff *skb;
- struct request_sock *req;
- __u32 seq;
+ struct request_sock *fastopen;
+ __u32 seq, snd_una;
__u32 remaining;
int err;
struct net *net = dev_net(icmp_skb->dev);
icsk = inet_csk(sk);
tp = tcp_sk(sk);
- req = tp->fastopen_rsk;
seq = ntohl(th->seq);
+ /* XXX (TFO) - tp->snd_una should be ISN (tcp_create_openreq_child() */
+ fastopen = tp->fastopen_rsk;
+ snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una;
if (sk->sk_state != TCP_LISTEN &&
- !between(seq, tp->snd_una, tp->snd_nxt) &&
- (req == NULL || seq != tcp_rsk(req)->snt_isn)) {
- /* For a Fast Open socket, allow seq to be snt_isn. */
+ !between(seq, snd_una, tp->snd_nxt)) {
NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
goto out;
}
if (code != ICMP_NET_UNREACH && code != ICMP_HOST_UNREACH)
break;
if (seq != tp->snd_una || !icsk->icsk_retransmits ||
- !icsk->icsk_backoff)
+ !icsk->icsk_backoff || fastopen)
break;
- /* XXX (TFO) - revisit the following logic for TFO */
-
if (sock_owned_by_user(sk))
break;
goto out;
}
- /* XXX (TFO) - if it's a TFO socket and has been accepted, rather
- * than following the TCP_SYN_RECV case and closing the socket,
- * we ignore the ICMP error and keep trying like a fully established
- * socket. Is this the right thing to do?
- */
- if (req && req->sk == NULL)
- goto out;
-
switch (sk->sk_state) {
struct request_sock *req, **prev;
case TCP_LISTEN:
goto out;
case TCP_SYN_SENT:
- case TCP_SYN_RECV: /* Cannot happen.
- It can f.e. if SYNs crossed,
- or Fast Open.
- */
+ case TCP_SYN_RECV:
+ /* Only in fast or simultaneous open. If a fast open socket is
+ * is already accepted it is treated as a connected one below.
+ */
+ if (fastopen && fastopen->sk == NULL)
+ break;
+
if (!sock_owned_by_user(sk)) {
sk->sk_err = err;
*/
static int tcp_v4_send_synack(struct sock *sk, struct dst_entry *dst,
struct request_sock *req,
- u16 queue_mapping)
+ u16 queue_mapping,
+ struct tcp_fastopen_cookie *foc)
{
const struct inet_request_sock *ireq = inet_rsk(req);
struct flowi4 fl4;
if (!dst && (dst = inet_csk_route_req(sk, &fl4, req)) == NULL)
return -1;
- skb = tcp_make_synack(sk, dst, req, NULL);
+ skb = tcp_make_synack(sk, dst, req, foc);
if (skb) {
__tcp_v4_send_check(skb, ireq->ir_loc_addr, ireq->ir_rmt_addr);
static int tcp_v4_rtx_synack(struct sock *sk, struct request_sock *req)
{
- int res = tcp_v4_send_synack(sk, NULL, req, 0);
+ int res = tcp_v4_send_synack(sk, NULL, req, 0, NULL);
if (!res) {
TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_RETRANSSEGS);
};
#endif
-static bool tcp_fastopen_check(struct sock *sk, struct sk_buff *skb,
- struct request_sock *req,
- struct tcp_fastopen_cookie *foc,
- struct tcp_fastopen_cookie *valid_foc)
-{
- bool skip_cookie = false;
- struct fastopen_queue *fastopenq;
-
- if (likely(!fastopen_cookie_present(foc))) {
- /* See include/net/tcp.h for the meaning of these knobs */
- if ((sysctl_tcp_fastopen & TFO_SERVER_ALWAYS) ||
- ((sysctl_tcp_fastopen & TFO_SERVER_COOKIE_NOT_REQD) &&
- (TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq + 1)))
- skip_cookie = true; /* no cookie to validate */
- else
- return false;
- }
- fastopenq = inet_csk(sk)->icsk_accept_queue.fastopenq;
- /* A FO option is present; bump the counter. */
- NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPFASTOPENPASSIVE);
-
- /* Make sure the listener has enabled fastopen, and we don't
- * exceed the max # of pending TFO requests allowed before trying
- * to validating the cookie in order to avoid burning CPU cycles
- * unnecessarily.
- *
- * XXX (TFO) - The implication of checking the max_qlen before
- * processing a cookie request is that clients can't differentiate
- * between qlen overflow causing Fast Open to be disabled
- * temporarily vs a server not supporting Fast Open at all.
- */
- if ((sysctl_tcp_fastopen & TFO_SERVER_ENABLE) == 0 ||
- fastopenq == NULL || fastopenq->max_qlen == 0)
- return false;
-
- if (fastopenq->qlen >= fastopenq->max_qlen) {
- struct request_sock *req1;
- spin_lock(&fastopenq->lock);
- req1 = fastopenq->rskq_rst_head;
- if ((req1 == NULL) || time_after(req1->expires, jiffies)) {
- spin_unlock(&fastopenq->lock);
- NET_INC_STATS_BH(sock_net(sk),
- LINUX_MIB_TCPFASTOPENLISTENOVERFLOW);
- /* Avoid bumping LINUX_MIB_TCPFASTOPENPASSIVEFAIL*/
- foc->len = -1;
- return false;
- }
- fastopenq->rskq_rst_head = req1->dl_next;
- fastopenq->qlen--;
- spin_unlock(&fastopenq->lock);
- reqsk_free(req1);
- }
- if (skip_cookie) {
- tcp_rsk(req)->rcv_nxt = TCP_SKB_CB(skb)->end_seq;
- return true;
- }
-
- if (foc->len == TCP_FASTOPEN_COOKIE_SIZE) {
- if ((sysctl_tcp_fastopen & TFO_SERVER_COOKIE_NOT_CHKED) == 0) {
- tcp_fastopen_cookie_gen(ip_hdr(skb)->saddr,
- ip_hdr(skb)->daddr, valid_foc);
- if ((valid_foc->len != TCP_FASTOPEN_COOKIE_SIZE) ||
- memcmp(&foc->val[0], &valid_foc->val[0],
- TCP_FASTOPEN_COOKIE_SIZE) != 0)
- return false;
- valid_foc->len = -1;
- }
- /* Acknowledge the data received from the peer. */
- tcp_rsk(req)->rcv_nxt = TCP_SKB_CB(skb)->end_seq;
- return true;
- } else if (foc->len == 0) { /* Client requesting a cookie */
- tcp_fastopen_cookie_gen(ip_hdr(skb)->saddr,
- ip_hdr(skb)->daddr, valid_foc);
- NET_INC_STATS_BH(sock_net(sk),
- LINUX_MIB_TCPFASTOPENCOOKIEREQD);
- } else {
- /* Client sent a cookie with wrong size. Treat it
- * the same as invalid and return a valid one.
- */
- tcp_fastopen_cookie_gen(ip_hdr(skb)->saddr,
- ip_hdr(skb)->daddr, valid_foc);
- }
- return false;
-}
-
-static int tcp_v4_conn_req_fastopen(struct sock *sk,
- struct sk_buff *skb,
- struct sk_buff *skb_synack,
- struct request_sock *req)
-{
- struct tcp_sock *tp = tcp_sk(sk);
- struct request_sock_queue *queue = &inet_csk(sk)->icsk_accept_queue;
- const struct inet_request_sock *ireq = inet_rsk(req);
- struct sock *child;
- int err;
-
- req->num_retrans = 0;
- req->num_timeout = 0;
- req->sk = NULL;
-
- child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL);
- if (child == NULL) {
- NET_INC_STATS_BH(sock_net(sk),
- LINUX_MIB_TCPFASTOPENPASSIVEFAIL);
- kfree_skb(skb_synack);
- return -1;
- }
- err = ip_build_and_send_pkt(skb_synack, sk, ireq->ir_loc_addr,
- ireq->ir_rmt_addr, ireq->opt);
- err = net_xmit_eval(err);
- if (!err)
- tcp_rsk(req)->snt_synack = tcp_time_stamp;
- /* XXX (TFO) - is it ok to ignore error and continue? */
-
- spin_lock(&queue->fastopenq->lock);
- queue->fastopenq->qlen++;
- spin_unlock(&queue->fastopenq->lock);
-
- /* Initialize the child socket. Have to fix some values to take
- * into account the child is a Fast Open socket and is created
- * only out of the bits carried in the SYN packet.
- */
- tp = tcp_sk(child);
-
- tp->fastopen_rsk = req;
- /* Do a hold on the listner sk so that if the listener is being
- * closed, the child that has been accepted can live on and still
- * access listen_lock.
- */
- sock_hold(sk);
- tcp_rsk(req)->listener = sk;
-
- /* RFC1323: The window in SYN & SYN/ACK segments is never
- * scaled. So correct it appropriately.
- */
- tp->snd_wnd = ntohs(tcp_hdr(skb)->window);
-
- /* Activate the retrans timer so that SYNACK can be retransmitted.
- * The request socket is not added to the SYN table of the parent
- * because it's been added to the accept queue directly.
- */
- inet_csk_reset_xmit_timer(child, ICSK_TIME_RETRANS,
- TCP_TIMEOUT_INIT, TCP_RTO_MAX);
-
- /* Add the child socket directly into the accept queue */
- inet_csk_reqsk_queue_add(sk, req, child);
-
- /* Now finish processing the fastopen child socket. */
- inet_csk(child)->icsk_af_ops->rebuild_header(child);
- tcp_init_congestion_control(child);
- tcp_mtup_init(child);
- tcp_init_metrics(child);
- tcp_init_buffer_space(child);
-
- /* Queue the data carried in the SYN packet. We need to first
- * bump skb's refcnt because the caller will attempt to free it.
- *
- * XXX (TFO) - we honor a zero-payload TFO request for now.
- * (Any reason not to?)
- */
- if (TCP_SKB_CB(skb)->end_seq == TCP_SKB_CB(skb)->seq + 1) {
- /* Don't queue the skb if there is no payload in SYN.
- * XXX (TFO) - How about SYN+FIN?
- */
- tp->rcv_nxt = TCP_SKB_CB(skb)->end_seq;
- } else {
- skb = skb_get(skb);
- skb_dst_drop(skb);
- __skb_pull(skb, tcp_hdr(skb)->doff * 4);
- skb_set_owner_r(skb, child);
- __skb_queue_tail(&child->sk_receive_queue, skb);
- tp->rcv_nxt = TCP_SKB_CB(skb)->end_seq;
- tp->syn_data_acked = 1;
- }
- sk->sk_data_ready(sk);
- bh_unlock_sock(child);
- sock_put(child);
- WARN_ON(req->sk == NULL);
- return 0;
-}
-
int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
{
struct tcp_options_received tmp_opt;
__be32 saddr = ip_hdr(skb)->saddr;
__be32 daddr = ip_hdr(skb)->daddr;
__u32 isn = TCP_SKB_CB(skb)->when;
- bool want_cookie = false;
+ bool want_cookie = false, fastopen;
struct flowi4 fl4;
struct tcp_fastopen_cookie foc = { .len = -1 };
- struct tcp_fastopen_cookie valid_foc = { .len = -1 };
- struct sk_buff *skb_synack;
- int do_fastopen;
+ int err;
/* Never answer to SYNs send to broadcast or multicast */
if (skb_rtable(skb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST))
ireq->ir_rmt_addr = saddr;
ireq->no_srccheck = inet_sk(sk)->transparent;
ireq->opt = tcp_v4_save_options(skb);
+ ireq->ir_mark = inet_request_mark(sk, skb);
if (security_inet_conn_request(sk, skb, req))
goto drop_and_free;
isn = tcp_v4_init_sequence(skb);
}
- tcp_rsk(req)->snt_isn = isn;
-
- if (dst == NULL) {
- dst = inet_csk_route_req(sk, &fl4, req);
- if (dst == NULL)
- goto drop_and_free;
- }
- do_fastopen = tcp_fastopen_check(sk, skb, req, &foc, &valid_foc);
-
- /* We don't call tcp_v4_send_synack() directly because we need
- * to make sure a child socket can be created successfully before
- * sending back synack!
- *
- * XXX (TFO) - Ideally one would simply call tcp_v4_send_synack()
- * (or better yet, call tcp_send_synack() in the child context
- * directly, but will have to fix bunch of other code first)
- * after syn_recv_sock() except one will need to first fix the
- * latter to remove its dependency on the current implementation
- * of tcp_v4_send_synack()->tcp_select_initial_window().
- */
- skb_synack = tcp_make_synack(sk, dst, req,
- fastopen_cookie_present(&valid_foc) ? &valid_foc : NULL);
-
- if (skb_synack) {
- __tcp_v4_send_check(skb_synack, ireq->ir_loc_addr, ireq->ir_rmt_addr);
- skb_set_queue_mapping(skb_synack, skb_get_queue_mapping(skb));
- } else
+ if (!dst && (dst = inet_csk_route_req(sk, &fl4, req)) == NULL)
goto drop_and_free;
- if (likely(!do_fastopen)) {
- int err;
- err = ip_build_and_send_pkt(skb_synack, sk, ireq->ir_loc_addr,
- ireq->ir_rmt_addr, ireq->opt);
- err = net_xmit_eval(err);
+ tcp_rsk(req)->snt_isn = isn;
+ tcp_rsk(req)->snt_synack = tcp_time_stamp;
+ tcp_openreq_init_rwin(req, sk, dst);
+ fastopen = !want_cookie &&
+ tcp_try_fastopen(sk, skb, req, &foc, dst);
+ err = tcp_v4_send_synack(sk, dst, req,
+ skb_get_queue_mapping(skb), &foc);
+ if (!fastopen) {
if (err || want_cookie)
goto drop_and_free;
tcp_rsk(req)->snt_synack = tcp_time_stamp;
tcp_rsk(req)->listener = NULL;
- /* Add the request_sock to the SYN table */
inet_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT);
- if (fastopen_cookie_present(&foc) && foc.len != 0)
- NET_INC_STATS_BH(sock_net(sk),
- LINUX_MIB_TCPFASTOPENPASSIVEFAIL);
- } else if (tcp_v4_conn_req_fastopen(sk, skb, skb_synack, req))
- goto drop_and_free;
+ }
return 0;
return sk;
}
-static __sum16 tcp_v4_checksum_init(struct sk_buff *skb)
-{
- const struct iphdr *iph = ip_hdr(skb);
-
- if (skb->ip_summed == CHECKSUM_COMPLETE) {
- if (!tcp_v4_check(skb->len, iph->saddr,
- iph->daddr, skb->csum)) {
- skb->ip_summed = CHECKSUM_UNNECESSARY;
- return 0;
- }
- }
-
- skb->csum = csum_tcpudp_nofold(iph->saddr, iph->daddr,
- skb->len, IPPROTO_TCP, 0);
-
- if (skb->len <= 76) {
- return __skb_checksum_complete(skb);
- }
- return 0;
-}
-
-
/* The socket must have it's spinlock held when we get
* here.
*
* Packet length and doff are validated by header prediction,
* provided case of th->doff==0 is eliminated.
* So, we defer the checks. */
- if (!skb_csum_unnecessary(skb) && tcp_v4_checksum_init(skb))
+
+ if (skb_checksum_init(skb, IPPROTO_TCP, inet_compute_pseudo))
goto csum_error;
th = tcp_hdr(skb);
projects / karo-tx-linux.git / blobdiff