TCPCT part 1a: add request_values parameter for sending SYNACK
Add optional function parameters associated with sending SYNACK.
These parameters are not needed after sending SYNACK, and are not
used for retransmission. Avoids extending struct tcp_request_sock,
and avoids allocating kernel memory.
Also affects DCCP as it uses common struct request_sock_ops,
but this parameter is currently reserved for future use.
Signed-off-by: William.Allen.Simpson@gmail.com
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/request_sock.h b/include/net/request_sock.h
index c719084..c9b50eb 100644
--- a/include/net/request_sock.h
+++ b/include/net/request_sock.h
@@ -27,13 +27,19 @@
struct dst_entry;
struct proto;
+/* empty to "strongly type" an otherwise void parameter.
+ */
+struct request_values {
+};
+
struct request_sock_ops {
int family;
int obj_size;
struct kmem_cache *slab;
char *slab_name;
int (*rtx_syn_ack)(struct sock *sk,
- struct request_sock *req);
+ struct request_sock *req,
+ struct request_values *rvp);
void (*send_ack)(struct sock *sk, struct sk_buff *skb,
struct request_sock *req);
void (*send_reset)(struct sock *sk,
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 325bfcf..ec183fd 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -440,7 +440,8 @@
extern struct sk_buff * tcp_make_synack(struct sock *sk,
struct dst_entry *dst,
- struct request_sock *req);
+ struct request_sock *req,
+ struct request_values *rvp);
extern int tcp_disconnect(struct sock *sk, int flags);
diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c
index 2423a08..efbcfdc 100644
--- a/net/dccp/ipv4.c
+++ b/net/dccp/ipv4.c
@@ -477,7 +477,8 @@
return &rt->u.dst;
}
-static int dccp_v4_send_response(struct sock *sk, struct request_sock *req)
+static int dccp_v4_send_response(struct sock *sk, struct request_sock *req,
+ struct request_values *rv_unused)
{
int err = -1;
struct sk_buff *skb;
@@ -626,7 +627,7 @@
dreq->dreq_iss = dccp_v4_init_sequence(skb);
dreq->dreq_service = service;
- if (dccp_v4_send_response(sk, req))
+ if (dccp_v4_send_response(sk, req, NULL))
goto drop_and_free;
inet_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index 50ea91a..6574215 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -241,7 +241,8 @@
}
-static int dccp_v6_send_response(struct sock *sk, struct request_sock *req)
+static int dccp_v6_send_response(struct sock *sk, struct request_sock *req,
+ struct request_values *rv_unused)
{
struct inet6_request_sock *ireq6 = inet6_rsk(req);
struct ipv6_pinfo *np = inet6_sk(sk);
@@ -468,7 +469,7 @@
dreq->dreq_iss = dccp_v6_init_sequence(skb);
dreq->dreq_service = service;
- if (dccp_v6_send_response(sk, req))
+ if (dccp_v6_send_response(sk, req, NULL))
goto drop_and_free;
inet6_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
diff --git a/net/dccp/minisocks.c b/net/dccp/minisocks.c
index 5ca49ce..af226a0 100644
--- a/net/dccp/minisocks.c
+++ b/net/dccp/minisocks.c
@@ -184,7 +184,7 @@
* counter (backoff, monitored by dccp_response_timer).
*/
req->retrans++;
- req->rsk_ops->rtx_syn_ack(sk, req);
+ req->rsk_ops->rtx_syn_ack(sk, req, NULL);
}
/* Network Duplicate, discard packet */
return NULL;
diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
index 9b35c56..ee16475 100644
--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -531,7 +531,7 @@
&expire, &resend);
if (!expire &&
(!resend ||
- !req->rsk_ops->rtx_syn_ack(parent, req) ||
+ !req->rsk_ops->rtx_syn_ack(parent, req, NULL) ||
inet_rsk(req)->acked)) {
unsigned long timeo;
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index df18ce0..649a36d 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -742,8 +742,9 @@
* This still operates on a request_sock only, not on a big
* socket.
*/
-static int __tcp_v4_send_synack(struct sock *sk, struct request_sock *req,
- struct dst_entry *dst)
+static int __tcp_v4_send_synack(struct sock *sk, struct dst_entry *dst,
+ struct request_sock *req,
+ struct request_values *rvp)
{
const struct inet_request_sock *ireq = inet_rsk(req);
int err = -1;
@@ -753,7 +754,7 @@
if (!dst && (dst = inet_csk_route_req(sk, req)) == NULL)
return -1;
- skb = tcp_make_synack(sk, dst, req);
+ skb = tcp_make_synack(sk, dst, req, rvp);
if (skb) {
struct tcphdr *th = tcp_hdr(skb);
@@ -774,9 +775,10 @@
return err;
}
-static int tcp_v4_send_synack(struct sock *sk, struct request_sock *req)
+static int tcp_v4_send_synack(struct sock *sk, struct request_sock *req,
+ struct request_values *rvp)
{
- return __tcp_v4_send_synack(sk, req, NULL);
+ return __tcp_v4_send_synack(sk, NULL, req, rvp);
}
/*
@@ -1211,13 +1213,13 @@
int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
{
- struct inet_request_sock *ireq;
struct tcp_options_received tmp_opt;
struct request_sock *req;
+ struct inet_request_sock *ireq;
+ struct dst_entry *dst = NULL;
__be32 saddr = ip_hdr(skb)->saddr;
__be32 daddr = ip_hdr(skb)->daddr;
__u32 isn = TCP_SKB_CB(skb)->when;
- struct dst_entry *dst = NULL;
#ifdef CONFIG_SYN_COOKIES
int want_cookie = 0;
#else
@@ -1337,7 +1339,7 @@
}
tcp_rsk(req)->snt_isn = isn;
- if (__tcp_v4_send_synack(sk, req, dst) || want_cookie)
+ if (__tcp_v4_send_synack(sk, dst, req, NULL) || want_cookie)
goto drop_and_free;
inet_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT);
diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c
index ab32c18..d3f6bbf 100644
--- a/net/ipv4/tcp_minisocks.c
+++ b/net/ipv4/tcp_minisocks.c
@@ -531,7 +531,7 @@
* Enforce "SYN-ACK" according to figure 8, figure 6
* of RFC793, fixed by RFC1122.
*/
- req->rsk_ops->rtx_syn_ack(sk, req);
+ req->rsk_ops->rtx_syn_ack(sk, req, NULL);
return NULL;
}
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 875bc6d..b8b2504 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -2224,7 +2224,8 @@
/* Prepare a SYN-ACK. */
struct sk_buff *tcp_make_synack(struct sock *sk, struct dst_entry *dst,
- struct request_sock *req)
+ struct request_sock *req,
+ struct request_values *rvp)
{
struct inet_request_sock *ireq = inet_rsk(req);
struct tcp_sock *tp = tcp_sk(sk);
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index de70909..da6e2441 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -461,7 +461,8 @@
}
-static int tcp_v6_send_synack(struct sock *sk, struct request_sock *req)
+static int tcp_v6_send_synack(struct sock *sk, struct request_sock *req,
+ struct request_values *rvp)
{
struct inet6_request_sock *treq = inet6_rsk(req);
struct ipv6_pinfo *np = inet6_sk(sk);
@@ -499,7 +500,7 @@
if ((err = xfrm_lookup(sock_net(sk), &dst, &fl, sk, 0)) < 0)
goto done;
- skb = tcp_make_synack(sk, dst, req);
+ skb = tcp_make_synack(sk, dst, req, rvp);
if (skb) {
struct tcphdr *th = tcp_hdr(skb);
@@ -1161,13 +1162,13 @@
*/
static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
{
+ struct tcp_options_received tmp_opt;
+ struct request_sock *req;
struct inet6_request_sock *treq;
struct ipv6_pinfo *np = inet6_sk(sk);
- struct tcp_options_received tmp_opt;
struct tcp_sock *tp = tcp_sk(sk);
- struct request_sock *req = NULL;
- __u32 isn = TCP_SKB_CB(skb)->when;
struct dst_entry *dst = __sk_dst_get(sk);
+ __u32 isn = TCP_SKB_CB(skb)->when;
#ifdef CONFIG_SYN_COOKIES
int want_cookie = 0;
#else
@@ -1239,23 +1240,19 @@
isn = tcp_v6_init_sequence(skb);
}
-
tcp_rsk(req)->snt_isn = isn;
security_inet_conn_request(sk, skb, req);
- if (tcp_v6_send_synack(sk, req))
- goto drop;
+ if (tcp_v6_send_synack(sk, req, NULL) || want_cookie)
+ goto drop_and_free;
- if (!want_cookie) {
- inet6_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT);
- return 0;
- }
+ inet6_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT);
+ return 0;
+drop_and_free:
+ reqsk_free(req);
drop:
- if (req)
- reqsk_free(req);
-
return 0; /* don't send reset */
}
