[linux-2.6-block.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>

/**
 * x25_parse_facilities - Parse facilities from skb into the facilities structs
 *
 * @skb: sk_buff to parse
 * @facilities: Regular facilities, updated as facilities are found
 * @dte_facs: ITU DTE facilities, updated as DTE facilities are found
 * @vc_fac_mask: mask is updated with all facilities found
 *
 * Return codes:
 *  -1 - Parsing error, caller should drop call and clean up
 *   0 - Parse OK, this skb has no facilities
 *  >0 - Parse OK, returns the length of the facilities header
 *
 */
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 -1;
			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 -1;
			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 -1;
			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 -1;
			switch (*p) {
			case X25_FAC_CALLING_AE:
				if (p[1] > X25_MAX_DTE_FACIL_LEN || p[1] <= 1)
					return -1;
				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 -1;
				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
95c30430	30	/**
	31	* x25_parse_facilities - Parse facilities from skb into the facilities structs
	32	*
	33	* @skb: sk_buff to parse
25985edc	34	* @facilities: Regular facilities, updated as facilities are found
95c30430	35	* @dte_facs: ITU DTE facilities, updated as DTE facilities are found
	36	* @vc_fac_mask: mask is updated with all facilities found
	37	*
	38	* Return codes:
	39	* -1 - Parsing error, caller should drop call and clean up
	40	* 0 - Parse OK, this skb has no facilities
	41	* >0 - Parse OK, returns the length of the facilities header
	42	*
1da177e4	43	*/
a64b7b93 SP	44	int x25_parse_facilities(struct sk_buff skb, struct x25_facilities facilities,
a64b7b93 SP	45	struct x25_dte_facilities dte_facs, unsigned long vc_fac_mask)
1da177e4 LT	46	{
1da177e4 LT	47	unsigned char *p = skb->data;
f5eb917b	48	unsigned int len;
1da177e4 LT	49
	50	*vc_fac_mask = 0;
	51
a64b7b93 SP	52	/*
	53	* The kernel knows which facilities were set on an incoming call but
	54	* currently this information is not available to userspace. Here we
	55	* give userspace who read incoming call facilities 0 length to indicate
	56	* it wasn't set.
	57	*/
	58	dte_facs->calling_len = 0;
	59	dte_facs->called_len = 0;
	60	memset(dte_facs->called_ae, '\0', sizeof(dte_facs->called_ae));
	61	memset(dte_facs->calling_ae, '\0', sizeof(dte_facs->calling_ae));
	62
f5eb917b JH	63	if (skb->len < 1)
	64	return 0;
	65
	66	len = *p++;
	67
	68	if (len >= skb->len)
	69	return -1;
	70
1da177e4 LT	71	while (len > 0) {
	72	switch (*p & X25_FAC_CLASS_MASK) {
	73	case X25_FAC_CLASS_A:
5ef41308	74	if (len < 2)
95c30430	75	return -1;
1da177e4 LT	76	switch (*p) {
1da177e4 LT	77	case X25_FAC_REVERSE:
ebc3f64b SP	78	if((p[1] & 0x81) == 0x81) {
	79	facilities->reverse = p[1] & 0x81;
	80	*vc_fac_mask \|= X25_MASK_REVERSE;
	81	break;
	82	}
	83
	84	if((p[1] & 0x01) == 0x01) {
	85	facilities->reverse = p[1] & 0x01;
	86	*vc_fac_mask \|= X25_MASK_REVERSE;
	87	break;
	88	}
	89
	90	if((p[1] & 0x80) == 0x80) {
	91	facilities->reverse = p[1] & 0x80;
	92	*vc_fac_mask \|= X25_MASK_REVERSE;
	93	break;
	94	}
	95
	96	if(p[1] == 0x00) {
	97	facilities->reverse
	98	= X25_DEFAULT_REVERSE;
	99	*vc_fac_mask \|= X25_MASK_REVERSE;
	100	break;
	101	}
	102
1da177e4 LT	103	case X25_FAC_THROUGHPUT:
	104	facilities->throughput = p[1];
	105	*vc_fac_mask \|= X25_MASK_THROUGHPUT;
	106	break;
a64b7b93 SP	107	case X25_MARKER:
a64b7b93 SP	108	break;
1da177e4 LT	109	default:
	110	printk(KERN_DEBUG "X.25: unknown facility "
	111	"%02X, value %02X\n",
	112	p[0], p[1]);
	113	break;
	114	}
	115	p += 2;
	116	len -= 2;
	117	break;
	118	case X25_FAC_CLASS_B:
5ef41308	119	if (len < 3)
95c30430	120	return -1;
1da177e4 LT	121	switch (*p) {
	122	case X25_FAC_PACKET_SIZE:
	123	facilities->pacsize_in = p[1];
	124	facilities->pacsize_out = p[2];
	125	*vc_fac_mask \|= X25_MASK_PACKET_SIZE;
	126	break;
	127	case X25_FAC_WINDOW_SIZE:
	128	facilities->winsize_in = p[1];
	129	facilities->winsize_out = p[2];
	130	*vc_fac_mask \|= X25_MASK_WINDOW_SIZE;
	131	break;
	132	default:
	133	printk(KERN_DEBUG "X.25: unknown facility "
	134	"%02X, values %02X, %02X\n",
	135	p[0], p[1], p[2]);
	136	break;
	137	}
	138	p += 3;
	139	len -= 3;
	140	break;
	141	case X25_FAC_CLASS_C:
5ef41308	142	if (len < 4)
95c30430	143	return -1;
1da177e4 LT	144	printk(KERN_DEBUG "X.25: unknown facility %02X, "
	145	"values %02X, %02X, %02X\n",
	146	p[0], p[1], p[2], p[3]);
	147	p += 4;
	148	len -= 4;
	149	break;
	150	case X25_FAC_CLASS_D:
5ef41308	151	if (len < p[1] + 2)
95c30430	152	return -1;
a64b7b93	153	switch (*p) {
f8e1d201	154	case X25_FAC_CALLING_AE:
a6331d6f	155	if (p[1] > X25_MAX_DTE_FACIL_LEN \|\| p[1] <= 1)
95c30430	156	return -1;
a64b7b93 SP	157	dte_facs->calling_len = p[2];
	158	memcpy(dte_facs->calling_ae, &p[3], p[1] - 1);
	159	*vc_fac_mask \|= X25_MASK_CALLING_AE;
	160	break;
	161	case X25_FAC_CALLED_AE:
a6331d6f	162	if (p[1] > X25_MAX_DTE_FACIL_LEN \|\| p[1] <= 1)
95c30430	163	return -1;
a64b7b93 SP	164	dte_facs->called_len = p[2];
	165	memcpy(dte_facs->called_ae, &p[3], p[1] - 1);
	166	*vc_fac_mask \|= X25_MASK_CALLED_AE;
	167	break;
	168	default:
	169	printk(KERN_DEBUG "X.25: unknown facility %02X,"
5ef41308	170	"length %d\n", p[0], p[1]);
a64b7b93 SP	171	break;
a64b7b93 SP	172	}
1da177e4	173	len -= p[1] + 2;
a64b7b93	174	p += p[1] + 2;
1da177e4 LT	175	break;
	176	}
	177	}
	178
	179	return p - skb->data;
	180	}
	181
	182	/*
	183	* Create a set of facilities.
	184	*/
	185	int x25_create_facilities(unsigned char *buffer,
a64b7b93 SP	186	struct x25_facilities *facilities,
a64b7b93 SP	187	struct x25_dte_facilities *dte_facs, unsigned long facil_mask)
1da177e4 LT	188	{
	189	unsigned char *p = buffer + 1;
	190	int len;
	191
	192	if (!facil_mask) {
	193	/*
	194	* Length of the facilities field in call_req or
	195	* call_accept packets
	196	*/
	197	buffer[0] = 0;
	198	len = 1; /* 1 byte for the length field */
	199	return len;
	200	}
	201
	202	if (facilities->reverse && (facil_mask & X25_MASK_REVERSE)) {
	203	*p++ = X25_FAC_REVERSE;
ebc3f64b	204	*p++ = facilities->reverse;
1da177e4 LT	205	}
	206
	207	if (facilities->throughput && (facil_mask & X25_MASK_THROUGHPUT)) {
	208	*p++ = X25_FAC_THROUGHPUT;
	209	*p++ = facilities->throughput;
	210	}
	211
	212	if ((facilities->pacsize_in \|\| facilities->pacsize_out) &&
	213	(facil_mask & X25_MASK_PACKET_SIZE)) {
	214	*p++ = X25_FAC_PACKET_SIZE;
	215	*p++ = facilities->pacsize_in ? : facilities->pacsize_out;
	216	*p++ = facilities->pacsize_out ? : facilities->pacsize_in;
	217	}
	218
	219	if ((facilities->winsize_in \|\| facilities->winsize_out) &&
	220	(facil_mask & X25_MASK_WINDOW_SIZE)) {
	221	*p++ = X25_FAC_WINDOW_SIZE;
	222	*p++ = facilities->winsize_in ? : facilities->winsize_out;
	223	*p++ = facilities->winsize_out ? : facilities->winsize_in;
	224	}
	225
a64b7b93 SP	226	if (facil_mask & (X25_MASK_CALLING_AE\|X25_MASK_CALLED_AE)) {
	227	*p++ = X25_MARKER;
	228	*p++ = X25_DTE_SERVICES;
	229	}
	230
	231	if (dte_facs->calling_len && (facil_mask & X25_MASK_CALLING_AE)) {
6bf1574e	232	unsigned bytecount = (dte_facs->calling_len + 1) >> 1;
a64b7b93 SP	233	*p++ = X25_FAC_CALLING_AE;
	234	*p++ = 1 + bytecount;
	235	*p++ = dte_facs->calling_len;
	236	memcpy(p, dte_facs->calling_ae, bytecount);
	237	p += bytecount;
	238	}
	239
	240	if (dte_facs->called_len && (facil_mask & X25_MASK_CALLED_AE)) {
	241	unsigned bytecount = (dte_facs->called_len % 2) ?
	242	dte_facs->called_len / 2 + 1 :
	243	dte_facs->called_len / 2;
	244	*p++ = X25_FAC_CALLED_AE;
	245	*p++ = 1 + bytecount;
	246	*p++ = dte_facs->called_len;
	247	memcpy(p, dte_facs->called_ae, bytecount);
	248	p+=bytecount;
	249	}
	250
1da177e4 LT	251	len = p - buffer;
	252	buffer[0] = len - 1;
	253
	254	return len;
	255	}
	256
	257	/*
	258	* Try to reach a compromise on a set of facilities.
	259	*
	260	* The only real problem is with reverse charging.
	261	*/
	262	int x25_negotiate_facilities(struct sk_buff skb, struct sock sk,
a64b7b93	263	struct x25_facilities new, struct x25_dte_facilities dte)
1da177e4 LT	264	{
	265	struct x25_sock *x25 = x25_sk(sk);
	266	struct x25_facilities *ours = &x25->facilities;
	267	struct x25_facilities theirs;
	268	int len;
	269
	270	memset(&theirs, 0, sizeof(theirs));
	271	memcpy(new, ours, sizeof(*new));
	272
a64b7b93	273	len = x25_parse_facilities(skb, &theirs, dte, &x25->vc_facil_mask);
f5eb917b JH	274	if (len < 0)
f5eb917b JH	275	return len;
1da177e4 LT	276
	277	/*
	278	* They want reverse charging, we won't accept it.
	279	*/
ebc3f64b	280	if ((theirs.reverse & 0x01 ) && (ours->reverse & 0x01)) {
d2e7543c	281	SOCK_DEBUG(sk, "X.25: rejecting reverse charging request\n");
1da177e4 LT	282	return -1;
	283	}
	284
	285	new->reverse = theirs.reverse;
	286
	287	if (theirs.throughput) {
ddd0451f JH	288	int theirs_in = theirs.throughput & 0x0f;
	289	int theirs_out = theirs.throughput & 0xf0;
	290	int ours_in = ours->throughput & 0x0f;
	291	int ours_out = ours->throughput & 0xf0;
	292	if (!ours_in \|\| theirs_in < ours_in) {
	293	SOCK_DEBUG(sk, "X.25: inbound throughput negotiated\n");
	294	new->throughput = (new->throughput & 0xf0) \| theirs_in;
	295	}
	296	if (!ours_out \|\| theirs_out < ours_out) {
	297	SOCK_DEBUG(sk,
	298	"X.25: outbound throughput negotiated\n");
	299	new->throughput = (new->throughput & 0x0f) \| theirs_out;
1da177e4 LT	300	}
	301	}
	302
	303	if (theirs.pacsize_in && theirs.pacsize_out) {
	304	if (theirs.pacsize_in < ours->pacsize_in) {
d2e7543c	305	SOCK_DEBUG(sk, "X.25: packet size inwards negotiated down\n");
1da177e4 LT	306	new->pacsize_in = theirs.pacsize_in;
	307	}
	308	if (theirs.pacsize_out < ours->pacsize_out) {
d2e7543c	309	SOCK_DEBUG(sk, "X.25: packet size outwards negotiated down\n");
1da177e4 LT	310	new->pacsize_out = theirs.pacsize_out;
	311	}
	312	}
	313
	314	if (theirs.winsize_in && theirs.winsize_out) {
	315	if (theirs.winsize_in < ours->winsize_in) {
d2e7543c	316	SOCK_DEBUG(sk, "X.25: window size inwards negotiated down\n");
1da177e4 LT	317	new->winsize_in = theirs.winsize_in;
	318	}
	319	if (theirs.winsize_out < ours->winsize_out) {
d2e7543c	320	SOCK_DEBUG(sk, "X.25: window size outwards negotiated down\n");
1da177e4 LT	321	new->winsize_out = theirs.winsize_out;
	322	}
	323	}
	324
	325	return len;
	326	}
	327
	328	/*
f8e1d201	329	* Limit values of certain facilities according to the capability of the
1da177e4 LT	330	* currently attached x25 link.
	331	*/
	332	void x25_limit_facilities(struct x25_facilities *facilities,
	333	struct x25_neigh *nb)
	334	{
	335
	336	if (!nb->extended) {
	337	if (facilities->winsize_in > 7) {
	338	printk(KERN_DEBUG "X.25: incoming winsize limited to 7\n");
	339	facilities->winsize_in = 7;
	340	}
	341	if (facilities->winsize_out > 7) {
	342	facilities->winsize_out = 7;
	343	printk( KERN_DEBUG "X.25: outgoing winsize limited to 7\n");
	344	}
	345	}
	346	}