From ebc3f64b864fc16a594c2e63bf55a55c7d42084b Mon Sep 17 00:00:00 2001 From: Shaun Pereira Date: Wed, 22 Jun 2005 22:16:17 -0700 Subject: [X25]: Fast select with no restriction on response This patch is a follow up to patch 1 regarding "Selective Sub Address matching with call user data". It allows use of the Fast-Select-Acceptance optional user facility for X.25. This patch just implements fast select with no restriction on response (NRR). What this means (according to ITU-T Recomendation 10/96 section 6.16) is that if in an incoming call packet, the relevant facility bits are set for fast-select-NRR, then the called DTE can issue a direct response to the incoming packet using a call-accepted packet that contains call-user-data. This patch allows such a response. The called DTE can also respond with a clear-request packet that contains call-user-data. However, this feature is currently not implemented by the patch. How is Fast Select Acceptance used? By default, the system does not allow fast select acceptance (as before). To enable a response to fast select acceptance, After a listen socket in created and bound as follows socket(AF_X25, SOCK_SEQPACKET, 0); bind(call_soc, (struct sockaddr *)&locl_addr, sizeof(locl_addr)); but before a listen system call is made, the following ioctl should be used. ioctl(call_soc,SIOCX25CALLACCPTAPPRV); Now the listen system call can be made listen(call_soc, 4); After this, an incoming-call packet will be accepted, but no call-accepted packet will be sent back until the following system call is made on the socket that accepts the call ioctl(vc_soc,SIOCX25SENDCALLACCPT); The network (or cisco xot router used for testing here) will allow the application server's call-user-data in the call-accepted packet, provided the call-request was made with Fast-select NRR. Signed-off-by: Shaun Pereira Signed-off-by: Andrew Morton Signed-off-by: David S. Miller --- net/x25/af_x25.c | 37 +++++++++++++++++++++++++++++++++---- 1 file changed, 33 insertions(+), 4 deletions(-) (limited to 'net/x25/af_x25.c') diff --git a/net/x25/af_x25.c b/net/x25/af_x25.c index e17d84a55d5..04bec047fa9 100644 --- a/net/x25/af_x25.c +++ b/net/x25/af_x25.c @@ -31,6 +31,8 @@ * x25_proc.c, using seq_file * 2005-04-02 Shaun Pereira Selective sub address matching * with call user data + * 2005-04-15 Shaun Pereira Fast select with no restriction on + * response */ #include @@ -502,6 +504,8 @@ static int x25_create(struct socket *sock, int protocol) x25->t2 = sysctl_x25_ack_holdback_timeout; x25->state = X25_STATE_0; x25->cudmatchlength = 0; + x25->accptapprv = X25_DENY_ACCPT_APPRV; /* normally no cud */ + /* on call accept */ x25->facilities.winsize_in = X25_DEFAULT_WINDOW_SIZE; x25->facilities.winsize_out = X25_DEFAULT_WINDOW_SIZE; @@ -551,6 +555,7 @@ static struct sock *x25_make_new(struct sock *osk) x25->facilities = ox25->facilities; x25->qbitincl = ox25->qbitincl; x25->cudmatchlength = ox25->cudmatchlength; + x25->accptapprv = ox25->accptapprv; x25_init_timers(sk); out: @@ -900,9 +905,11 @@ int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb, makex25->vc_facil_mask &= ~X25_MASK_REVERSE; makex25->cudmatchlength = x25_sk(sk)->cudmatchlength; - x25_write_internal(make, X25_CALL_ACCEPTED); - - makex25->state = X25_STATE_3; + /* Normally all calls are accepted immediatly */ + if(makex25->accptapprv & X25_DENY_ACCPT_APPRV) { + x25_write_internal(make, X25_CALL_ACCEPTED); + makex25->state = X25_STATE_3; + } /* * Incoming Call User Data. @@ -1294,7 +1301,8 @@ static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) if (facilities.throughput < 0x03 || facilities.throughput > 0xDD) break; - if (facilities.reverse && facilities.reverse != 1) + if (facilities.reverse && + (facilities.reverse | 0x81)!= 0x81) break; x25->facilities = facilities; rc = 0; @@ -1348,6 +1356,27 @@ static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) break; } + case SIOCX25CALLACCPTAPPRV: { + rc = -EINVAL; + if (sk->sk_state != TCP_CLOSE) + break; + x25->accptapprv = X25_ALLOW_ACCPT_APPRV; + rc = 0; + break; + } + + case SIOCX25SENDCALLACCPT: { + rc = -EINVAL; + if (sk->sk_state != TCP_ESTABLISHED) + break; + if (x25->accptapprv) /* must call accptapprv above */ + break; + x25_write_internal(sk, X25_CALL_ACCEPTED); + x25->state = X25_STATE_3; + rc = 0; + break; + } + default: rc = dev_ioctl(cmd, argp); break; -- cgit v1.2.3