Subject: Re: [PATCH] X25: Add ITU-T facilites

From: Andrew Hendry <[email-masked]>
Date: Mon, 24 Oct 2005 11:01:20 +1000

Structure alignment corrected.

Adds options for ITU DTE facilities to X.25, called address extension and calling address extension

Signed-off-by: Andrew Hendry <[email-masked]>

diff -uprN -X dontdiff linux-2.6.13.4-vanilla/include/linux/x25.h linux-2.6.13.4/include/linux/x25.h
--- linux-2.6.13.4-vanilla/include/linux/x25.h	2005-10-11 04:54:29.000000000 +1000
+++ linux-2.6.13.4/include/linux/x25.h	2005-10-21 09:20:53.000000000 +1000
@@ -11,6 +11,8 @@
 #ifndef	X25_KERNEL_H
 #define	X25_KERNEL_H
 
+#include <linux/types.h>
+
 #define	SIOCX25GSUBSCRIP	(SIOCPROTOPRIVATE + 0)
 #define	SIOCX25SSUBSCRIP	(SIOCPROTOPRIVATE + 1)
 #define	SIOCX25GFACILITIES	(SIOCPROTOPRIVATE + 2)
@@ -21,6 +23,8 @@
 #define SIOCX25SCUDMATCHLEN	(SIOCPROTOPRIVATE + 7)
 #define SIOCX25CALLACCPTAPPRV   (SIOCPROTOPRIVATE + 8)
 #define SIOCX25SENDCALLACCPT    (SIOCPROTOPRIVATE + 9)
+#define SIOCX25GDTEFACILITIES   (SIOCPROTOPRIVATE + 10)
+#define SIOCX25SDTEFACILITIES   (SIOCPROTOPRIVATE + 11)
 
 /*
  *	Values for {get,set}sockopt.
@@ -77,6 +81,8 @@ struct x25_subscrip_struct {
 #define	X25_MASK_PACKET_SIZE	0x04
 #define	X25_MASK_WINDOW_SIZE	0x08
 
+#define X25_MASK_CALLING_AE     0x10
+#define X25_MASK_CALLED_AE      0x20

 /*
@@ -98,6 +104,26 @@ struct x25_facilities {
 	unsigned int	reverse;
 };
 
+/* 
+*     ITU DTE facilities
+*     Only the called and calling address
+*     extension are currently implemented.
+*     The rest are in place to avoid the struct
+*     changing size if someone needs them later
+*/
+
+struct x25_dte_facilities {
+	__u16		delay_cumul;
+	__u16		delay_target;
+	__u16		delay_max;
+	__u8		min_throughput;
+	__u8		expedited;
+	__u8		calling_len;
+	__u8		called_len;
+	__u8		calling_ae[20];
+	__u8		called_ae[20];
+};
+
 /*
  *	Call User Data structure.
  */
diff -uprN -X dontdiff linux-2.6.13.4-vanilla/include/net/x25.h linux-2.6.13.4/include/net/x25.h
--- linux-2.6.13.4-vanilla/include/net/x25.h	2005-10-11 04:54:29.000000000 +1000
+++ linux-2.6.13.4/include/net/x25.h	2005-10-21 09:20:16.000000000 +1000
@@ -101,9 +101,16 @@ enum {
 #define	X25_FAC_PACKET_SIZE	0x42
 #define	X25_FAC_WINDOW_SIZE	0x43
 
-#define	X25_MAX_FAC_LEN		20		/* Plenty to spare */
+#define	X25_MAX_FAC_LEN		60
 #define	X25_MAX_CUD_LEN		128
 
+#define X25_FAC_CALLING_AE      0xCB
+#define X25_FAC_CALLED_AE       0xC9
+
+#define X25_MARKER              0x00
+#define X25_DTE_SERVICES        0x0F
+#define X25_MAX_AE_LEN          32
+
 /**
  *	struct x25_route - x25 routing entry
  *	@node - entry in x25_list_lock
@@ -148,6 +155,7 @@ struct x25_sock {
 	struct timer_list	timer;
 	struct x25_causediag	causediag;
 	struct x25_facilities	facilities;
+	struct x25_dte_facilities dte_facilities;
 	struct x25_calluserdata	calluserdata;
 	unsigned long 		vc_facil_mask;	/* inc_call facilities mask */
 };
@@ -180,9 +188,9 @@ extern void x25_establish_link(struct x2
 extern void x25_terminate_link(struct x25_neigh *);
 
 /* x25_facilities.c */
-extern int  x25_parse_facilities(struct sk_buff *, struct x25_facilities *, unsigned long *);
-extern int  x25_create_facilities(unsigned char *, struct x25_facilities *, unsigned long);
-extern int  x25_negotiate_facilities(struct sk_buff *, struct sock *, struct x25_facilities *);
+extern int  x25_parse_facilities(struct sk_buff *, struct x25_facilities *, struct x25_dte_facilities *, unsigned long *);
+extern int  x25_create_facilities(unsigned char *, struct x25_facilities *, struct x25_dte_facilities *, unsigned long);
+extern int  x25_negotiate_facilities(struct sk_buff *, struct sock *, struct x25_facilities *, struct x25_dte_facilities *);
 extern void x25_limit_facilities(struct x25_facilities *, struct x25_neigh *);
 
 /* x25_in.c */
diff -uprN -X dontdiff linux-2.6.13.4-vanilla/net/x25/af_x25.c linux-2.6.13.4/net/x25/af_x25.c
--- linux-2.6.13.4-vanilla/net/x25/af_x25.c	2005-10-11 04:54:29.000000000 +1000
+++ linux-2.6.13.4/net/x25/af_x25.c	2005-10-21 09:20:16.000000000 +1000
@@ -513,6 +513,13 @@ static int x25_create(struct socket *soc
 	x25->facilities.pacsize_out = X25_DEFAULT_PACKET_SIZE;
 	x25->facilities.throughput  = X25_DEFAULT_THROUGHPUT;
 	x25->facilities.reverse     = X25_DEFAULT_REVERSE;
+	x25->dte_facilities.calling_len	= 0;
+	x25->dte_facilities.called_len	= 0;
+	memset(x25->dte_facilities.called_ae, '\0',
+		sizeof(x25->dte_facilities.called_ae));
+	memset(x25->dte_facilities.calling_ae, '\0',
+		sizeof(x25->dte_facilities.calling_ae));
+	
 	rc = 0;
 out:
 	return rc;
@@ -554,6 +561,7 @@ static struct sock *x25_make_new(struct 
 	x25->t2         = ox25->t2;
 	x25->facilities = ox25->facilities;
 	x25->qbitincl   = ox25->qbitincl;
+	x25->dte_facilities = ox25->dte_facilities;
 	x25->cudmatchlength = ox25->cudmatchlength;
 	x25->accptapprv = ox25->accptapprv;
 
@@ -833,6 +841,7 @@ int x25_rx_call_request(struct sk_buff *
 	struct x25_sock *makex25;
 	struct x25_address source_addr, dest_addr;
 	struct x25_facilities facilities;
+	struct x25_dte_facilities dte_facilities;
 	int len, rc;
 
 	/*
@@ -869,7 +878,8 @@ int x25_rx_call_request(struct sk_buff *
 	/*
 	 *	Try to reach a compromise on the requested facilities.
 	 */
-	if ((len = x25_negotiate_facilities(skb, sk, &facilities)) == -1)
+	if ((len = x25_negotiate_facilities(skb, sk, &facilities, 
+		&dte_facilities)) == -1)
 		goto out_sock_put;
 
 	/*
@@ -900,9 +910,12 @@ int x25_rx_call_request(struct sk_buff *
 	makex25->source_addr   = source_addr;
 	makex25->neighbour     = nb;
 	makex25->facilities    = facilities;
+	makex25->dte_facilities= dte_facilities;
 	makex25->vc_facil_mask = x25_sk(sk)->vc_facil_mask;
 	/* ensure no reverse facil on accept */
 	makex25->vc_facil_mask &= ~X25_MASK_REVERSE;
+	/* ensure no calling address extension on accept */
+	makex25->vc_facil_mask &= ~X25_MASK_CALLING_AE;
 	makex25->cudmatchlength = x25_sk(sk)->cudmatchlength;
 
 	/* Normally all calls are accepted immediatly */
@@ -1309,6 +1322,34 @@ static int x25_ioctl(struct socket *sock
 			break;
 		}
 
+		case SIOCX25GDTEFACILITIES: {
+			rc = copy_to_user(argp, &x25->dte_facilities,
+				sizeof(x25->dte_facilities)) ? -EFAULT : 0;
+			break;
+		}
+
+		case SIOCX25SDTEFACILITIES: {
+			struct x25_dte_facilities dtefacs;
+			rc = -EFAULT;
+			if (copy_from_user(&dtefacs, argp, sizeof(dtefacs)))
+				break;
+			rc = -EINVAL;
+			if (sk->sk_state != TCP_LISTEN &&
+			    sk->sk_state != TCP_CLOSE)
+				break;
+			if (dtefacs.calling_len > X25_MAX_AE_LEN)
+				break;
+			if (dtefacs.calling_ae == NULL)
+				break;
+			if (dtefacs.called_len > X25_MAX_AE_LEN)
+				break;
+			if (dtefacs.called_ae == NULL)
+				break;
+			x25->dte_facilities = dtefacs;
+			rc = 0;
+			break;
+		}
+
 		case SIOCX25GCALLUSERDATA: {
 			struct x25_calluserdata cud = x25->calluserdata;
 			rc = copy_to_user(argp, &cud,
diff -uprN -X dontdiff linux-2.6.13.4-vanilla/net/x25/x25_facilities.c linux-2.6.13.4/net/x25/x25_facilities.c
--- linux-2.6.13.4-vanilla/net/x25/x25_facilities.c	2005-10-11 04:54:29.000000000 +1000
+++ linux-2.6.13.4/net/x25/x25_facilities.c	2005-10-21 09:20:16.000000000 +1000
@@ -28,11 +28,12 @@
 #include <net/x25.h>
 
 /*
- *	Parse a set of facilities into the facilities structure. Unrecognised
+ *	Parse a set of facilities into the facilities structures. Unrecognised
  *	facilities are written to the debug log file.
  */
 int x25_parse_facilities(struct sk_buff *skb,
 			 struct x25_facilities *facilities,
+			 struct x25_dte_facilities *dte_facs,
 			 unsigned long *vc_fac_mask)
 {
 	unsigned char *p = skb->data;
@@ -40,6 +41,16 @@ int x25_parse_facilities(struct sk_buff 
 
 	*vc_fac_mask = 0;
 
+	/* The kernel knows which facilities were set on an incoming call
+	 * but currently this information is not available to userspace.
+	 * Here we give userspace who read incoming call facilities
+	 * 0 length to indicate it wasn't set.
+	 */
+	dte_facs->calling_len = 0;
+	dte_facs->called_len = 0;
+	memset(dte_facs->called_ae, '\0', sizeof(dte_facs->called_ae));
+	memset(dte_facs->calling_ae, '\0', sizeof(dte_facs->calling_ae));
+
 	while (len > 0) {
 		switch (*p & X25_FAC_CLASS_MASK) {
 		case X25_FAC_CLASS_A:
@@ -74,6 +85,8 @@ int x25_parse_facilities(struct sk_buff 
 				facilities->throughput = p[1];
 				*vc_fac_mask |= X25_MASK_THROUGHPUT;
 				break;
+			case X25_MARKER:
+				break;
 			default:
 				printk(KERN_DEBUG "X.25: unknown facility "
 				       "%02X, value %02X\n",
@@ -112,9 +125,28 @@ int x25_parse_facilities(struct sk_buff 
 			len -= 4;
 			break;
 		case X25_FAC_CLASS_D:
-			printk(KERN_DEBUG "X.25: unknown facility %02X, "
-			       "length %d, values %02X, %02X, %02X, %02X\n",
-			       p[0], p[1], p[2], p[3], p[4], p[5]);
+			switch (*p) {
+			case X25_FAC_CALLING_AE:
+				if (p[1] > 33)
+					break;
+				dte_facs->calling_len = p[2];
+				memcpy(dte_facs->calling_ae, &p[3], p[1] - 1);
+				*vc_fac_mask |= X25_MASK_CALLING_AE;
+				break;
+			case X25_FAC_CALLED_AE:
+				if (p[1] > 33)
+					break;
+				dte_facs->called_len = p[2];
+				memcpy(dte_facs->called_ae, &p[3], p[1] - 1);
+				*vc_fac_mask |= X25_MASK_CALLED_AE;
+				break;
+			default:	
+				printk(KERN_DEBUG "X.25: unknown facility %02X,"
+				"length %d, values %02X, %02X, %02X, %02X\n",
+				 p[0], p[1], p[2], p[3], p[4], p[5]);
+				break;
+			}
+
 			len -= p[1] + 2;
 			p   += p[1] + 2;
 			break;
@@ -129,6 +161,7 @@ int x25_parse_facilities(struct sk_buff 
  */
 int x25_create_facilities(unsigned char *buffer,
 			  struct x25_facilities *facilities,
+			  struct x25_dte_facilities *dte_facs,
 			  unsigned long facil_mask)
 {
 	unsigned char *p = buffer + 1;
@@ -168,6 +201,34 @@ int x25_create_facilities(unsigned char 
 		*p++ = facilities->winsize_out ? : facilities->winsize_in;
 	}
 
+	if ((facil_mask & X25_MASK_CALLING_AE) || 
+	     (facil_mask & X25_MASK_CALLED_AE)) {
+		*p++ = X25_MARKER;
+		*p++ = X25_DTE_SERVICES;
+	}
+
+	if (dte_facs->calling_len && (facil_mask & X25_MASK_CALLING_AE)) {
+		unsigned bytecount = (dte_facs->calling_len % 2) ?
+                        dte_facs->calling_len / 2 + 1 :
+			dte_facs->calling_len / 2;
+		*p++ = X25_FAC_CALLING_AE;
+		*p++ = 1 + bytecount;
+		*p++ = dte_facs->calling_len;
+		memcpy(p, dte_facs->calling_ae, bytecount);
+		p+=bytecount;
+	}
+
+	if (dte_facs->called_len && (facil_mask & X25_MASK_CALLED_AE)) {
+		unsigned bytecount = (dte_facs->called_len % 2) ?
+                        dte_facs->called_len / 2 + 1 :
+			dte_facs->called_len / 2;
+		*p++ = X25_FAC_CALLED_AE;
+		*p++ = 1 + bytecount;
+		*p++ = dte_facs->called_len;
+		memcpy(p, dte_facs->called_ae, bytecount);
+		p+=bytecount;
+	}
+
 	len       = p - buffer;
 	buffer[0] = len - 1;
 
@@ -180,7 +241,8 @@ int x25_create_facilities(unsigned char 
  *	The only real problem is with reverse charging.
  */
 int x25_negotiate_facilities(struct sk_buff *skb, struct sock *sk,
-			     struct x25_facilities *new)
+			     struct x25_facilities *new,
+			     struct x25_dte_facilities *dte)
 {
 	struct x25_sock *x25 = x25_sk(sk);
 	struct x25_facilities *ours = &x25->facilities;
@@ -190,7 +252,7 @@ int x25_negotiate_facilities(struct sk_b
 	memset(&theirs, 0, sizeof(theirs));
 	memcpy(new, ours, sizeof(*new));
 
-	len = x25_parse_facilities(skb, &theirs, &x25->vc_facil_mask);
+	len = x25_parse_facilities(skb, &theirs, dte, &x25->vc_facil_mask);
 
 	/*
 	 *	They want reverse charging, we won't accept it.
diff -uprN -X dontdiff linux-2.6.13.4-vanilla/net/x25/x25_in.c linux-2.6.13.4/net/x25/x25_in.c
--- linux-2.6.13.4-vanilla/net/x25/x25_in.c	2005-10-11 04:54:29.000000000 +1000
+++ linux-2.6.13.4/net/x25/x25_in.c	2005-10-21 09:20:16.000000000 +1000
@@ -106,6 +106,7 @@ static int x25_state1_machine(struct soc
 			skb_pull(skb, x25_addr_ntoa(skb->data, &source_addr, &dest_addr));
 			skb_pull(skb,
 				 x25_parse_facilities(skb, &x25->facilities,
+						      &x25->dte_facilities,
 						      &x25->vc_facil_mask));
 			/*
 			 *	Copy any Call User Data.
diff -uprN -X dontdiff linux-2.6.13.4-vanilla/net/x25/x25_subr.c linux-2.6.13.4/net/x25/x25_subr.c
--- linux-2.6.13.4-vanilla/net/x25/x25_subr.c	2005-10-11 04:54:29.000000000 +1000
+++ linux-2.6.13.4/net/x25/x25_subr.c	2005-10-21 09:20:16.000000000 +1000
@@ -191,6 +191,7 @@ void x25_write_internal(struct sock *sk,
 			memcpy(dptr, addresses, len);
 			len     = x25_create_facilities(facilities,
 							&x25->facilities,
+							&x25->dte_facilities,
 					     x25->neighbour->global_facil_mask);
 			dptr    = skb_put(skb, len);
 			memcpy(dptr, facilities, len);
@@ -206,6 +207,7 @@ void x25_write_internal(struct sock *sk,
 			*dptr++ = 0x00;		/* Address lengths */
 			len     = x25_create_facilities(facilities,
 							&x25->facilities,
+							&x25->dte_facilities,
 							x25->vc_facil_mask);
 			dptr    = skb_put(skb, len);
 			memcpy(dptr, facilities, len);