We will support arbitrary SYN Cookie with BPF, and then some reqsk fields
are initialised in kfunc, and others are done in cookie_v[46]_check().
This patch factorises the common part as cookie_tcp_reqsk_init() and
calls it in cookie_tcp_reqsk_alloc() to minimise the discrepancy between
cookie_v[46]_check().
Signed-off-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
---
net/ipv4/syncookies.c | 69 ++++++++++++++++++++++++-------------------
net/ipv6/syncookies.c | 14 ---------
2 files changed, 38 insertions(+), 45 deletions(-)
diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c
index 1e3783c97e28..9bca1c026525 100644
--- a/net/ipv4/syncookies.c
+++ b/net/ipv4/syncookies.c
@@ -285,10 +285,44 @@ bool cookie_ecn_ok(const struct tcp_options_received *tcp_opt,
}
EXPORT_SYMBOL(cookie_ecn_ok);
+static int cookie_tcp_reqsk_init(struct sock *sk, struct sk_buff *skb,
+ struct request_sock *req)
+{
+ struct inet_request_sock *ireq = inet_rsk(req);
+ struct tcp_request_sock *treq = tcp_rsk(req);
+ const struct tcphdr *th = tcp_hdr(skb);
+
+ req->num_retrans = 0;
+
+ ireq->ir_num = ntohs(th->dest);
+ ireq->ir_rmt_port = th->source;
+ ireq->ir_iif = inet_request_bound_dev_if(sk, skb);
+ ireq->ir_mark = inet_request_mark(sk, skb);
+
+ if (IS_ENABLED(CONFIG_SMC))
+ ireq->smc_ok = 0;
+
+ treq->snt_synack = 0;
+ treq->tfo_listener = false;
+ treq->txhash = net_tx_rndhash();
+ treq->rcv_isn = ntohl(th->seq) - 1;
+ treq->snt_isn = ntohl(th->ack_seq) - 1;
+ treq->syn_tos = TCP_SKB_CB(skb)->ip_dsfield;
+ treq->syn_tos = TCP_SKB_CB(skb)->ip_dsfield;
+ treq->req_usec_ts = false;
+
+#if IS_ENABLED(CONFIG_MPTCP)
+ treq->is_mptcp = sk_is_mptcp(sk);
+ if (treq->is_mptcp)
+ return mptcp_subflow_init_cookie_req(req, sk, skb);
+#endif
+
+ return 0;
+}
+
struct request_sock *cookie_tcp_reqsk_alloc(const struct request_sock_ops *ops,
struct sock *sk, struct sk_buff *skb)
{
- struct tcp_request_sock *treq;
struct request_sock *req;
if (sk_is_mptcp(sk))
@@ -299,22 +333,10 @@ struct request_sock *cookie_tcp_reqsk_alloc(const struct request_sock_ops *ops,
if (!req)
return NULL;
- treq = tcp_rsk(req);
-
- treq->syn_tos = TCP_SKB_CB(skb)->ip_dsfield;
- treq->req_usec_ts = false;
-
-#if IS_ENABLED(CONFIG_MPTCP)
- treq->is_mptcp = sk_is_mptcp(sk);
- if (treq->is_mptcp) {
- int err = mptcp_subflow_init_cookie_req(req, sk, skb);
-
- if (err) {
- reqsk_free(req);
- return NULL;
- }
+ if (cookie_tcp_reqsk_init(sk, skb, req)) {
+ reqsk_free(req);
+ return NULL;
}
-#endif
return req;
}
@@ -376,28 +398,15 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb)
ireq = inet_rsk(req);
treq = tcp_rsk(req);
- treq->rcv_isn = ntohl(th->seq) - 1;
- treq->snt_isn = ntohl(th->ack_seq) - 1;
treq->ts_off = tsoff;
- treq->txhash = net_tx_rndhash();
req->mss = mss;
- ireq->ir_num = ntohs(th->dest);
- ireq->ir_rmt_port = th->source;
sk_rcv_saddr_set(req_to_sk(req), ip_hdr(skb)->daddr);
sk_daddr_set(req_to_sk(req), ip_hdr(skb)->saddr);
- ireq->ir_mark = inet_request_mark(sk, skb);
ireq->snd_wscale = tcp_opt.snd_wscale;
ireq->sack_ok = tcp_opt.sack_ok;
ireq->wscale_ok = tcp_opt.wscale_ok;
ireq->tstamp_ok = tcp_opt.saw_tstamp;
req->ts_recent = tcp_opt.saw_tstamp ? tcp_opt.rcv_tsval : 0;
- treq->snt_synack = 0;
- treq->tfo_listener = false;
-
- if (IS_ENABLED(CONFIG_SMC))
- ireq->smc_ok = 0;
-
- ireq->ir_iif = inet_request_bound_dev_if(sk, skb);
/* We throwed the options of the initial SYN away, so we hope
* the ACK carries the same options again (see RFC1122 4.2.3.8)
@@ -409,8 +418,6 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb)
tcp_ao_syncookie(sk, skb, req, AF_INET);
- req->num_retrans = 0;
-
/*
* We need to lookup the route here to get at the correct
* window size. We should better make sure that the window size
diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c
index 12b1809245f9..e0a9220d1536 100644
--- a/net/ipv6/syncookies.c
+++ b/net/ipv6/syncookies.c
@@ -178,11 +178,8 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
ireq = inet_rsk(req);
treq = tcp_rsk(req);
- treq->tfo_listener = false;
req->mss = mss;
- ireq->ir_rmt_port = th->source;
- ireq->ir_num = ntohs(th->dest);
ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr;
ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr;
@@ -196,31 +193,20 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
ireq->pktopts = skb;
}
- ireq->ir_iif = inet_request_bound_dev_if(sk, skb);
/* So that link locals have meaning */
if (!sk->sk_bound_dev_if &&
ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL)
ireq->ir_iif = tcp_v6_iif(skb);
- ireq->ir_mark = inet_request_mark(sk, skb);
-
- req->num_retrans = 0;
ireq->snd_wscale = tcp_opt.snd_wscale;
ireq->sack_ok = tcp_opt.sack_ok;
ireq->wscale_ok = tcp_opt.wscale_ok;
ireq->tstamp_ok = tcp_opt.saw_tstamp;
req->ts_recent = tcp_opt.saw_tstamp ? tcp_opt.rcv_tsval : 0;
- treq->snt_synack = 0;
- treq->rcv_isn = ntohl(th->seq) - 1;
- treq->snt_isn = ntohl(th->ack_seq) - 1;
treq->ts_off = tsoff;
- treq->txhash = net_tx_rndhash();
tcp_ao_syncookie(sk, skb, req, AF_INET6);
- if (IS_ENABLED(CONFIG_SMC))
- ireq->smc_ok = 0;
-
/*
* We need to lookup the dst_entry to get the correct window size.
* This is taken from tcp_v6_syn_recv_sock. Somebody please enlighten
--
2.30.2
