2019-12-09 07:22:35

by Martin Schiller

Subject: [PATCH v2] net/x25: add new state X25_STATE_5

This is needed, because if the flag X25_ACCPT_APPRV_FLAG is not set on a
socket (manual call confirmation) and the channel is cleared by remote
before the manual call confirmation was sent, this situation needs to
be handled.

Signed-off-by: Martin Schiller <[email protected]>
---
include/net/x25.h | 3 ++-
net/x25/af_x25.c | 8 ++++++++
net/x25/x25_in.c | 32 ++++++++++++++++++++++++++++++++
3 files changed, 42 insertions(+), 1 deletion(-)

diff --git a/include/net/x25.h b/include/net/x25.h
index ed1acc3044ac..d7d6c2b4ffa7 100644
--- a/include/net/x25.h
+++ b/include/net/x25.h
@@ -62,7 +62,8 @@ enum {
X25_STATE_1, /* Awaiting Call Accepted */
X25_STATE_2, /* Awaiting Clear Confirmation */
X25_STATE_3, /* Data Transfer */
- X25_STATE_4 /* Awaiting Reset Confirmation */
+ X25_STATE_4, /* Awaiting Reset Confirmation */
+ X25_STATE_5 /* Call Accepted / Call Connected pending */
};

enum {
diff --git a/net/x25/af_x25.c b/net/x25/af_x25.c
index c34f7d077604..2efe44a34644 100644
--- a/net/x25/af_x25.c
+++ b/net/x25/af_x25.c
@@ -659,6 +659,12 @@ static int x25_release(struct socket *sock)
sock_set_flag(sk, SOCK_DEAD);
sock_set_flag(sk, SOCK_DESTROY);
break;
+
+ case X25_STATE_5:
+ x25_write_internal(sk, X25_CLEAR_REQUEST);
+ x25_disconnect(sk, 0, 0, 0);
+ __x25_destroy_socket(sk);
+ goto out;
}

sock_orphan(sk);
@@ -1054,6 +1060,8 @@ int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb,
if (test_bit(X25_ACCPT_APPRV_FLAG, &makex25->flags)) {
x25_write_internal(make, X25_CALL_ACCEPTED);
makex25->state = X25_STATE_3;
+ } else {
+ makex25->state = X25_STATE_5;
}

/*
diff --git a/net/x25/x25_in.c b/net/x25/x25_in.c
index f97c43344e95..4d3bb46aaae0 100644
--- a/net/x25/x25_in.c
+++ b/net/x25/x25_in.c
@@ -382,6 +382,35 @@ static int x25_state4_machine(struct sock *sk, struct sk_buff *skb, int frametyp
return 0;
}

+/*
+ * State machine for state 5, Call Accepted / Call Connected pending (X25_ACCPT_APPRV_FLAG).
+ * The handling of the timer(s) is in file x25_timer.c
+ * Handling of state 0 and connection release is in af_x25.c.
+ */
+static int x25_state5_machine(struct sock *sk, struct sk_buff *skb, int frametype)
+{
+ struct x25_sock *x25 = x25_sk(sk);
+
+ switch (frametype) {
+ case X25_CLEAR_REQUEST:
+ if (!pskb_may_pull(skb, X25_STD_MIN_LEN + 2)) {
+ x25_write_internal(sk, X25_CLEAR_REQUEST);
+ x25->state = X25_STATE_2;
+ x25_start_t23timer(sk);
+ return 0;
+ }
+
+ x25_write_internal(sk, X25_CLEAR_CONFIRMATION);
+ x25_disconnect(sk, 0, skb->data[3], skb->data[4]);
+ break;
+
+ default:
+ break;
+ }
+
+ return 0;
+}
+
/* Higher level upcall for a LAPB frame */
int x25_process_rx_frame(struct sock *sk, struct sk_buff *skb)
{
@@ -406,6 +435,9 @@ int x25_process_rx_frame(struct sock *sk, struct sk_buff *skb)
case X25_STATE_4:
queued = x25_state4_machine(sk, skb, frametype);
break;
+ case X25_STATE_5:
+ queued = x25_state5_machine(sk, skb, frametype);
+ break;
}

x25_kick(sk);
--
2.20.1

2019-12-09 18:33:45

by David Miller

Subject: Re: [PATCH v2] net/x25: add new state X25_STATE_5

From: Martin Schiller <[email protected]>
Date: Mon, 9 Dec 2019 08:21:34 +0100

> This is needed, because if the flag X25_ACCPT_APPRV_FLAG is not set on a
> socket (manual call confirmation) and the channel is cleared by remote
> before the manual call confirmation was sent, this situation needs to
> be handled.
>
> Signed-off-by: Martin Schiller <[email protected]>

Applied, thank you.