[net-next-2.6.git] / net / x25 / x25_facilities.c

/*
 *	X.25 Packet Layer release 002
 *
 *	This is ALPHA test software. This code may break your machine,
 *	randomly fail to work with new releases, misbehave and/or generally
 *	screw up. It might even work.
 *
 *	This code REQUIRES 2.1.15 or higher
 *
 *	This module:
 *		This module is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 *	History
 *	X.25 001	Split from x25_subr.c
 *	mar/20/00	Daniela Squassoni Disabling/enabling of facilities
 *					  negotiation.
 *	apr/14/05	Shaun Pereira - Allow fast select with no restriction
 *					on response.
 */

#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <net/x25.h>

/*
 * 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;
	unsigned int len;

	*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));

	if (skb->len < 1)
		return 0;

	len = *p++;

	if (len >= skb->len)
		return -1;

	while (len > 0) {
		switch (*p & X25_FAC_CLASS_MASK) {
		case X25_FAC_CLASS_A:
			if (len < 2)
				return 0;
			switch (*p) {
			case X25_FAC_REVERSE:
				if((p[1] & 0x81) == 0x81) {
					facilities->reverse = p[1] & 0x81;
					*vc_fac_mask |= X25_MASK_REVERSE;
					break;
				}

				if((p[1] & 0x01) == 0x01) {
					facilities->reverse = p[1] & 0x01;
					*vc_fac_mask |= X25_MASK_REVERSE;
					break;
				}

				if((p[1] & 0x80) == 0x80) {
					facilities->reverse = p[1] & 0x80;
					*vc_fac_mask |= X25_MASK_REVERSE;
					break;
				}

				if(p[1] == 0x00) {
					facilities->reverse
						= X25_DEFAULT_REVERSE;
					*vc_fac_mask |= X25_MASK_REVERSE;
					break;
				}

			case X25_FAC_THROUGHPUT:
				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",
				       p[0], p[1]);
				break;
			}
			p   += 2;
			len -= 2;
			break;
		case X25_FAC_CLASS_B:
			if (len < 3)
				return 0;
			switch (*p) {
			case X25_FAC_PACKET_SIZE:
				facilities->pacsize_in  = p[1];
				facilities->pacsize_out = p[2];
				*vc_fac_mask |= X25_MASK_PACKET_SIZE;
				break;
			case X25_FAC_WINDOW_SIZE:
				facilities->winsize_in  = p[1];
				facilities->winsize_out = p[2];
				*vc_fac_mask |= X25_MASK_WINDOW_SIZE;
				break;
			default:
				printk(KERN_DEBUG "X.25: unknown facility "
				       "%02X, values %02X, %02X\n",
				       p[0], p[1], p[2]);
				break;
			}
			p   += 3;
			len -= 3;
			break;
		case X25_FAC_CLASS_C:
			if (len < 4)
				return 0;
			printk(KERN_DEBUG "X.25: unknown facility %02X, "
			       "values %02X, %02X, %02X\n",
			       p[0], p[1], p[2], p[3]);
			p   += 4;
			len -= 4;
			break;
		case X25_FAC_CLASS_D:
			if (len < p[1] + 2)
				return 0;
			switch (*p) {
			case X25_FAC_CALLING_AE:
				if (p[1] > X25_MAX_DTE_FACIL_LEN || p[1] <= 1)
					return 0;
				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] > X25_MAX_DTE_FACIL_LEN || p[1] <= 1)
					return 0;
				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\n", p[0], p[1]);
				break;
			}
			len -= p[1] + 2;
			p += p[1] + 2;
			break;
		}
	}

	return p - skb->data;
}

/*
 *	Create a set of facilities.
 */
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;
	int len;

	if (!facil_mask) {
		/*
		 * Length of the facilities field in call_req or
		 * call_accept packets
		 */
		buffer[0] = 0;
		len = 1; /* 1 byte for the length field */
		return len;
	}

	if (facilities->reverse && (facil_mask & X25_MASK_REVERSE)) {
		*p++ = X25_FAC_REVERSE;
		*p++ = facilities->reverse;
	}

	if (facilities->throughput && (facil_mask & X25_MASK_THROUGHPUT)) {
		*p++ = X25_FAC_THROUGHPUT;
		*p++ = facilities->throughput;
	}

	if ((facilities->pacsize_in || facilities->pacsize_out) &&
	    (facil_mask & X25_MASK_PACKET_SIZE)) {
		*p++ = X25_FAC_PACKET_SIZE;
		*p++ = facilities->pacsize_in ? : facilities->pacsize_out;
		*p++ = facilities->pacsize_out ? : facilities->pacsize_in;
	}

	if ((facilities->winsize_in || facilities->winsize_out) &&
	    (facil_mask & X25_MASK_WINDOW_SIZE)) {
		*p++ = X25_FAC_WINDOW_SIZE;
		*p++ = facilities->winsize_in ? : facilities->winsize_out;
		*p++ = facilities->winsize_out ? : facilities->winsize_in;
	}

	if (facil_mask & (X25_MASK_CALLING_AE|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 + 1) >> 1;
		*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;

	return len;
}

/*
 *	Try to reach a compromise on a set of facilities.
 *
 *	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_dte_facilities *dte)
{
	struct x25_sock *x25 = x25_sk(sk);
	struct x25_facilities *ours = &x25->facilities;
	struct x25_facilities theirs;
	int len;

	memset(&theirs, 0, sizeof(theirs));
	memcpy(new, ours, sizeof(*new));

	len = x25_parse_facilities(skb, &theirs, dte, &x25->vc_facil_mask);
	if (len < 0)
		return len;

	/*
	 *	They want reverse charging, we won't accept it.
	 */
	if ((theirs.reverse & 0x01 ) && (ours->reverse & 0x01)) {
		SOCK_DEBUG(sk, "X.25: rejecting reverse charging request\n");
		return -1;
	}

	new->reverse = theirs.reverse;

	if (theirs.throughput) {
		int theirs_in =  theirs.throughput & 0x0f;
		int theirs_out = theirs.throughput & 0xf0;
		int ours_in  = ours->throughput & 0x0f;
		int ours_out = ours->throughput & 0xf0;
		if (!ours_in || theirs_in < ours_in) {
			SOCK_DEBUG(sk, "X.25: inbound throughput negotiated\n");
			new->throughput = (new->throughput & 0xf0) | theirs_in;
		}
		if (!ours_out || theirs_out < ours_out) {
			SOCK_DEBUG(sk,
				"X.25: outbound throughput negotiated\n");
			new->throughput = (new->throughput & 0x0f) | theirs_out;
		}
	}

	if (theirs.pacsize_in && theirs.pacsize_out) {
		if (theirs.pacsize_in < ours->pacsize_in) {
			SOCK_DEBUG(sk, "X.25: packet size inwards negotiated down\n");
			new->pacsize_in = theirs.pacsize_in;
		}
		if (theirs.pacsize_out < ours->pacsize_out) {
			SOCK_DEBUG(sk, "X.25: packet size outwards negotiated down\n");
			new->pacsize_out = theirs.pacsize_out;
		}
	}

	if (theirs.winsize_in && theirs.winsize_out) {
		if (theirs.winsize_in < ours->winsize_in) {
			SOCK_DEBUG(sk, "X.25: window size inwards negotiated down\n");
			new->winsize_in = theirs.winsize_in;
		}
		if (theirs.winsize_out < ours->winsize_out) {
			SOCK_DEBUG(sk, "X.25: window size outwards negotiated down\n");
			new->winsize_out = theirs.winsize_out;
		}
	}

	return len;
}

/*
 *	Limit values of certain facilities according to the capability of the
 *      currently attached x25 link.
 */
void x25_limit_facilities(struct x25_facilities *facilities,
			  struct x25_neigh *nb)
{

	if (!nb->extended) {
		if (facilities->winsize_in  > 7) {
			printk(KERN_DEBUG "X.25: incoming winsize limited to 7\n");
			facilities->winsize_in = 7;
		}
		if (facilities->winsize_out > 7) {
			facilities->winsize_out = 7;
			printk( KERN_DEBUG "X.25: outgoing winsize limited to 7\n");
		}
	}
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* X.25 Packet Layer release 002
	3	*
	4	* This is ALPHA test software. This code may break your machine,
	5	* randomly fail to work with new releases, misbehave and/or generally
f8e1d201	6	* screw up. It might even work.
1da177e4 LT	7	*
	8	* This code REQUIRES 2.1.15 or higher
	9	*
	10	* This module:
	11	* This module is free software; you can redistribute it and/or
	12	* modify it under the terms of the GNU General Public License
	13	* as published by the Free Software Foundation; either version
	14	* 2 of the License, or (at your option) any later version.
	15	*
	16	* History
	17	* X.25 001 Split from x25_subr.c
f8e1d201	18	* mar/20/00 Daniela Squassoni Disabling/enabling of facilities
1da177e4	19	* negotiation.
ebc3f64b SP	20	* apr/14/05 Shaun Pereira - Allow fast select with no restriction
ebc3f64b SP	21	* on response.
1da177e4 LT	22	*/
	23
	24	#include <linux/kernel.h>
	25	#include <linux/string.h>
	26	#include <linux/skbuff.h>
	27	#include <net/sock.h>
	28	#include <net/x25.h>
	29
	30	/*
a64b7b93	31	* Parse a set of facilities into the facilities structures. Unrecognised
1da177e4 LT	32	* facilities are written to the debug log file.
1da177e4 LT	33	*/
a64b7b93 SP	34	int x25_parse_facilities(struct sk_buff skb, struct x25_facilities facilities,
a64b7b93 SP	35	struct x25_dte_facilities dte_facs, unsigned long vc_fac_mask)
1da177e4 LT	36	{
1da177e4 LT	37	unsigned char *p = skb->data;
f5eb917b	38	unsigned int len;
1da177e4 LT	39
	40	*vc_fac_mask = 0;
	41
a64b7b93 SP	42	/*
	43	* The kernel knows which facilities were set on an incoming call but
	44	* currently this information is not available to userspace. Here we
	45	* give userspace who read incoming call facilities 0 length to indicate
	46	* it wasn't set.
	47	*/
	48	dte_facs->calling_len = 0;
	49	dte_facs->called_len = 0;
	50	memset(dte_facs->called_ae, '\0', sizeof(dte_facs->called_ae));
	51	memset(dte_facs->calling_ae, '\0', sizeof(dte_facs->calling_ae));
	52
f5eb917b JH	53	if (skb->len < 1)
	54	return 0;
	55
	56	len = *p++;
	57
	58	if (len >= skb->len)
	59	return -1;
	60
1da177e4 LT	61	while (len > 0) {
	62	switch (*p & X25_FAC_CLASS_MASK) {
	63	case X25_FAC_CLASS_A:
5ef41308 DR	64	if (len < 2)
5ef41308 DR	65	return 0;
1da177e4 LT	66	switch (*p) {
1da177e4 LT	67	case X25_FAC_REVERSE:
ebc3f64b SP	68	if((p[1] & 0x81) == 0x81) {
	69	facilities->reverse = p[1] & 0x81;
	70	*vc_fac_mask \|= X25_MASK_REVERSE;
	71	break;
	72	}
	73
	74	if((p[1] & 0x01) == 0x01) {
	75	facilities->reverse = p[1] & 0x01;
	76	*vc_fac_mask \|= X25_MASK_REVERSE;
	77	break;
	78	}
	79
	80	if((p[1] & 0x80) == 0x80) {
	81	facilities->reverse = p[1] & 0x80;
	82	*vc_fac_mask \|= X25_MASK_REVERSE;
	83	break;
	84	}
	85
	86	if(p[1] == 0x00) {
	87	facilities->reverse
	88	= X25_DEFAULT_REVERSE;
	89	*vc_fac_mask \|= X25_MASK_REVERSE;
	90	break;
	91	}
	92
1da177e4 LT	93	case X25_FAC_THROUGHPUT:
	94	facilities->throughput = p[1];
	95	*vc_fac_mask \|= X25_MASK_THROUGHPUT;
	96	break;
a64b7b93 SP	97	case X25_MARKER:
a64b7b93 SP	98	break;
1da177e4 LT	99	default:
	100	printk(KERN_DEBUG "X.25: unknown facility "
	101	"%02X, value %02X\n",
	102	p[0], p[1]);
	103	break;
	104	}
	105	p += 2;
	106	len -= 2;
	107	break;
	108	case X25_FAC_CLASS_B:
5ef41308 DR	109	if (len < 3)
5ef41308 DR	110	return 0;
1da177e4 LT	111	switch (*p) {
	112	case X25_FAC_PACKET_SIZE:
	113	facilities->pacsize_in = p[1];
	114	facilities->pacsize_out = p[2];
	115	*vc_fac_mask \|= X25_MASK_PACKET_SIZE;
	116	break;
	117	case X25_FAC_WINDOW_SIZE:
	118	facilities->winsize_in = p[1];
	119	facilities->winsize_out = p[2];
	120	*vc_fac_mask \|= X25_MASK_WINDOW_SIZE;
	121	break;
	122	default:
	123	printk(KERN_DEBUG "X.25: unknown facility "
	124	"%02X, values %02X, %02X\n",
	125	p[0], p[1], p[2]);
	126	break;
	127	}
	128	p += 3;
	129	len -= 3;
	130	break;
	131	case X25_FAC_CLASS_C:
5ef41308 DR	132	if (len < 4)
5ef41308 DR	133	return 0;
1da177e4 LT	134	printk(KERN_DEBUG "X.25: unknown facility %02X, "
	135	"values %02X, %02X, %02X\n",
	136	p[0], p[1], p[2], p[3]);
	137	p += 4;
	138	len -= 4;
	139	break;
	140	case X25_FAC_CLASS_D:
5ef41308 DR	141	if (len < p[1] + 2)
5ef41308 DR	142	return 0;
a64b7b93	143	switch (*p) {
f8e1d201	144	case X25_FAC_CALLING_AE:
a6331d6f	145	if (p[1] > X25_MAX_DTE_FACIL_LEN \|\| p[1] <= 1)
a6331d6f	146	return 0;
a64b7b93 SP	147	dte_facs->calling_len = p[2];
	148	memcpy(dte_facs->calling_ae, &p[3], p[1] - 1);
	149	*vc_fac_mask \|= X25_MASK_CALLING_AE;
	150	break;
	151	case X25_FAC_CALLED_AE:
a6331d6f	152	if (p[1] > X25_MAX_DTE_FACIL_LEN \|\| p[1] <= 1)
a6331d6f	153	return 0;
a64b7b93 SP	154	dte_facs->called_len = p[2];
	155	memcpy(dte_facs->called_ae, &p[3], p[1] - 1);
	156	*vc_fac_mask \|= X25_MASK_CALLED_AE;
	157	break;
	158	default:
	159	printk(KERN_DEBUG "X.25: unknown facility %02X,"
5ef41308	160	"length %d\n", p[0], p[1]);
a64b7b93 SP	161	break;
a64b7b93 SP	162	}
1da177e4	163	len -= p[1] + 2;
a64b7b93	164	p += p[1] + 2;
1da177e4 LT	165	break;
	166	}
	167	}
	168
	169	return p - skb->data;
	170	}
	171
	172	/*
	173	* Create a set of facilities.
	174	*/
	175	int x25_create_facilities(unsigned char *buffer,
a64b7b93 SP	176	struct x25_facilities *facilities,
a64b7b93 SP	177	struct x25_dte_facilities *dte_facs, unsigned long facil_mask)
1da177e4 LT	178	{
	179	unsigned char *p = buffer + 1;
	180	int len;
	181
	182	if (!facil_mask) {
	183	/*
	184	* Length of the facilities field in call_req or
	185	* call_accept packets
	186	*/
	187	buffer[0] = 0;
	188	len = 1; /* 1 byte for the length field */
	189	return len;
	190	}
	191
	192	if (facilities->reverse && (facil_mask & X25_MASK_REVERSE)) {
	193	*p++ = X25_FAC_REVERSE;
ebc3f64b	194	*p++ = facilities->reverse;
1da177e4 LT	195	}
	196
	197	if (facilities->throughput && (facil_mask & X25_MASK_THROUGHPUT)) {
	198	*p++ = X25_FAC_THROUGHPUT;
	199	*p++ = facilities->throughput;
	200	}
	201
	202	if ((facilities->pacsize_in \|\| facilities->pacsize_out) &&
	203	(facil_mask & X25_MASK_PACKET_SIZE)) {
	204	*p++ = X25_FAC_PACKET_SIZE;
	205	*p++ = facilities->pacsize_in ? : facilities->pacsize_out;
	206	*p++ = facilities->pacsize_out ? : facilities->pacsize_in;
	207	}
	208
	209	if ((facilities->winsize_in \|\| facilities->winsize_out) &&
	210	(facil_mask & X25_MASK_WINDOW_SIZE)) {
	211	*p++ = X25_FAC_WINDOW_SIZE;
	212	*p++ = facilities->winsize_in ? : facilities->winsize_out;
	213	*p++ = facilities->winsize_out ? : facilities->winsize_in;
	214	}
	215
a64b7b93 SP	216	if (facil_mask & (X25_MASK_CALLING_AE\|X25_MASK_CALLED_AE)) {
	217	*p++ = X25_MARKER;
	218	*p++ = X25_DTE_SERVICES;
	219	}
	220
	221	if (dte_facs->calling_len && (facil_mask & X25_MASK_CALLING_AE)) {
6bf1574e	222	unsigned bytecount = (dte_facs->calling_len + 1) >> 1;
a64b7b93 SP	223	*p++ = X25_FAC_CALLING_AE;
	224	*p++ = 1 + bytecount;
	225	*p++ = dte_facs->calling_len;
	226	memcpy(p, dte_facs->calling_ae, bytecount);
	227	p += bytecount;
	228	}
	229
	230	if (dte_facs->called_len && (facil_mask & X25_MASK_CALLED_AE)) {
	231	unsigned bytecount = (dte_facs->called_len % 2) ?
	232	dte_facs->called_len / 2 + 1 :
	233	dte_facs->called_len / 2;
	234	*p++ = X25_FAC_CALLED_AE;
	235	*p++ = 1 + bytecount;
	236	*p++ = dte_facs->called_len;
	237	memcpy(p, dte_facs->called_ae, bytecount);
	238	p+=bytecount;
	239	}
	240
1da177e4 LT	241	len = p - buffer;
	242	buffer[0] = len - 1;
	243
	244	return len;
	245	}
	246
	247	/*
	248	* Try to reach a compromise on a set of facilities.
	249	*
	250	* The only real problem is with reverse charging.
	251	*/
	252	int x25_negotiate_facilities(struct sk_buff skb, struct sock sk,
a64b7b93	253	struct x25_facilities new, struct x25_dte_facilities dte)
1da177e4 LT	254	{
	255	struct x25_sock *x25 = x25_sk(sk);
	256	struct x25_facilities *ours = &x25->facilities;
	257	struct x25_facilities theirs;
	258	int len;
	259
	260	memset(&theirs, 0, sizeof(theirs));
	261	memcpy(new, ours, sizeof(*new));
	262
a64b7b93	263	len = x25_parse_facilities(skb, &theirs, dte, &x25->vc_facil_mask);
f5eb917b JH	264	if (len < 0)
f5eb917b JH	265	return len;
1da177e4 LT	266
	267	/*
	268	* They want reverse charging, we won't accept it.
	269	*/
ebc3f64b	270	if ((theirs.reverse & 0x01 ) && (ours->reverse & 0x01)) {
d2e7543c	271	SOCK_DEBUG(sk, "X.25: rejecting reverse charging request\n");
1da177e4 LT	272	return -1;
	273	}
	274
	275	new->reverse = theirs.reverse;
	276
	277	if (theirs.throughput) {
ddd0451f JH	278	int theirs_in = theirs.throughput & 0x0f;
	279	int theirs_out = theirs.throughput & 0xf0;
	280	int ours_in = ours->throughput & 0x0f;
	281	int ours_out = ours->throughput & 0xf0;
	282	if (!ours_in \|\| theirs_in < ours_in) {
	283	SOCK_DEBUG(sk, "X.25: inbound throughput negotiated\n");
	284	new->throughput = (new->throughput & 0xf0) \| theirs_in;
	285	}
	286	if (!ours_out \|\| theirs_out < ours_out) {
	287	SOCK_DEBUG(sk,
	288	"X.25: outbound throughput negotiated\n");
	289	new->throughput = (new->throughput & 0x0f) \| theirs_out;
1da177e4 LT	290	}
	291	}
	292
	293	if (theirs.pacsize_in && theirs.pacsize_out) {
	294	if (theirs.pacsize_in < ours->pacsize_in) {
d2e7543c	295	SOCK_DEBUG(sk, "X.25: packet size inwards negotiated down\n");
1da177e4 LT	296	new->pacsize_in = theirs.pacsize_in;
	297	}
	298	if (theirs.pacsize_out < ours->pacsize_out) {
d2e7543c	299	SOCK_DEBUG(sk, "X.25: packet size outwards negotiated down\n");
1da177e4 LT	300	new->pacsize_out = theirs.pacsize_out;
	301	}
	302	}
	303
	304	if (theirs.winsize_in && theirs.winsize_out) {
	305	if (theirs.winsize_in < ours->winsize_in) {
d2e7543c	306	SOCK_DEBUG(sk, "X.25: window size inwards negotiated down\n");
1da177e4 LT	307	new->winsize_in = theirs.winsize_in;
	308	}
	309	if (theirs.winsize_out < ours->winsize_out) {
d2e7543c	310	SOCK_DEBUG(sk, "X.25: window size outwards negotiated down\n");
1da177e4 LT	311	new->winsize_out = theirs.winsize_out;
	312	}
	313	}
	314
	315	return len;
	316	}
	317
	318	/*
f8e1d201	319	* Limit values of certain facilities according to the capability of the
1da177e4 LT	320	* currently attached x25 link.
	321	*/
	322	void x25_limit_facilities(struct x25_facilities *facilities,
	323	struct x25_neigh *nb)
	324	{
	325
	326	if (!nb->extended) {
	327	if (facilities->winsize_in > 7) {
	328	printk(KERN_DEBUG "X.25: incoming winsize limited to 7\n");
	329	facilities->winsize_in = 7;
	330	}
	331	if (facilities->winsize_out > 7) {
	332	facilities->winsize_out = 7;
	333	printk( KERN_DEBUG "X.25: outgoing winsize limited to 7\n");
	334	}
	335	}
	336	}