[linux-2.6-block.git] / net / x25 / x25_facilities.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *	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
 *
 *	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.
 */

#define pr_fmt(fmt) "X25: " fmt

#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;
	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 (!pskb_may_pull(skb, 1))
		return 0;

	len = skb->data[0];

	if (!pskb_may_pull(skb, 1 + len))
		return -1;

	p = skb->data + 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;
				}
				fallthrough;
			case X25_FAC_THROUGHPUT:
				facilities->throughput = p[1];
				*vc_fac_mask |= X25_MASK_THROUGHPUT;
				break;
			case X25_MARKER:
				break;
			default:
				pr_debug("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:
				pr_debug("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;
			pr_debug("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;
				if (p[2] > X25_MAX_AE_LEN)
					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;
				if (p[2] > X25_MAX_AE_LEN)
					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:
				pr_debug("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 int 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 int 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));
	memset(dte, 0, sizeof(*dte));

	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)) {
		net_dbg_ratelimited("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) {
			net_dbg_ratelimited("X.25: inbound throughput negotiated\n");
			new->throughput = (new->throughput & 0xf0) | theirs_in;
		}
		if (!ours_out || theirs_out < ours_out) {
			net_dbg_ratelimited(
				"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) {
			net_dbg_ratelimited("X.25: packet size inwards negotiated down\n");
			new->pacsize_in = theirs.pacsize_in;
		}
		if (theirs.pacsize_out < ours->pacsize_out) {
			net_dbg_ratelimited("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) {
			net_dbg_ratelimited("X.25: window size inwards negotiated down\n");
			new->winsize_in = theirs.winsize_in;
		}
		if (theirs.winsize_out < ours->winsize_out) {
			net_dbg_ratelimited("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) {
			pr_debug("incoming winsize limited to 7\n");
			facilities->winsize_in = 7;
		}
		if (facilities->winsize_out > 7) {
			facilities->winsize_out = 7;
			pr_debug("outgoing winsize limited to 7\n");
		}
	}
}
Commit	Line	Data
ee5d8f4d	1	// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4 LT	2	/*
	3	* X.25 Packet Layer release 002
	4	*
	5	* This is ALPHA test software. This code may break your machine,
	6	* randomly fail to work with new releases, misbehave and/or generally
f8e1d201	7	* screw up. It might even work.
1da177e4 LT	8	*
	9	* This code REQUIRES 2.1.15 or higher
	10	*
1da177e4 LT	11	* History
1da177e4 LT	12	* X.25 001 Split from x25_subr.c
f8e1d201	13	* mar/20/00 Daniela Squassoni Disabling/enabling of facilities
1da177e4	14	* negotiation.
ebc3f64b SP	15	* apr/14/05 Shaun Pereira - Allow fast select with no restriction
ebc3f64b SP	16	* on response.
1da177e4 LT	17	*/
1da177e4 LT	18
b73e9e3c	19	#define pr_fmt(fmt) "X25: " fmt
b73e9e3c	20
1da177e4 LT	21	#include <linux/kernel.h>
	22	#include <linux/string.h>
	23	#include <linux/skbuff.h>
	24	#include <net/sock.h>
	25	#include <net/x25.h>
	26
95c30430	27	/**
	28	* x25_parse_facilities - Parse facilities from skb into the facilities structs
	29	*
	30	* @skb: sk_buff to parse
25985edc	31	* @facilities: Regular facilities, updated as facilities are found
95c30430	32	* @dte_facs: ITU DTE facilities, updated as DTE facilities are found
	33	* @vc_fac_mask: mask is updated with all facilities found
	34	*
	35	* Return codes:
	36	* -1 - Parsing error, caller should drop call and clean up
	37	* 0 - Parse OK, this skb has no facilities
	38	* >0 - Parse OK, returns the length of the facilities header
	39	*
1da177e4	40	*/
a64b7b93 SP	41	int x25_parse_facilities(struct sk_buff skb, struct x25_facilities facilities,
a64b7b93 SP	42	struct x25_dte_facilities dte_facs, unsigned long vc_fac_mask)
1da177e4	43	{
cb101ed2	44	unsigned char *p;
f5eb917b	45	unsigned int len;
1da177e4 LT	46
	47	*vc_fac_mask = 0;
	48
a64b7b93 SP	49	/*
	50	* The kernel knows which facilities were set on an incoming call but
	51	* currently this information is not available to userspace. Here we
	52	* give userspace who read incoming call facilities 0 length to indicate
	53	* it wasn't set.
	54	*/
	55	dte_facs->calling_len = 0;
	56	dte_facs->called_len = 0;
	57	memset(dte_facs->called_ae, '\0', sizeof(dte_facs->called_ae));
	58	memset(dte_facs->calling_ae, '\0', sizeof(dte_facs->calling_ae));
	59
cb101ed2	60	if (!pskb_may_pull(skb, 1))
f5eb917b JH	61	return 0;
f5eb917b JH	62
cb101ed2	63	len = skb->data[0];
f5eb917b	64
cb101ed2	65	if (!pskb_may_pull(skb, 1 + len))
f5eb917b JH	66	return -1;
f5eb917b JH	67
cb101ed2 MD	68	p = skb->data + 1;
cb101ed2 MD	69
1da177e4 LT	70	while (len > 0) {
	71	switch (*p & X25_FAC_CLASS_MASK) {
	72	case X25_FAC_CLASS_A:
5ef41308	73	if (len < 2)
95c30430	74	return -1;
1da177e4 LT	75	switch (*p) {
1da177e4 LT	76	case X25_FAC_REVERSE:
ebc3f64b SP	77	if((p[1] & 0x81) == 0x81) {
	78	facilities->reverse = p[1] & 0x81;
	79	*vc_fac_mask \|= X25_MASK_REVERSE;
	80	break;
	81	}
	82
	83	if((p[1] & 0x01) == 0x01) {
	84	facilities->reverse = p[1] & 0x01;
	85	*vc_fac_mask \|= X25_MASK_REVERSE;
	86	break;
	87	}
	88
	89	if((p[1] & 0x80) == 0x80) {
	90	facilities->reverse = p[1] & 0x80;
	91	*vc_fac_mask \|= X25_MASK_REVERSE;
	92	break;
	93	}
	94
	95	if(p[1] == 0x00) {
	96	facilities->reverse
	97	= X25_DEFAULT_REVERSE;
	98	*vc_fac_mask \|= X25_MASK_REVERSE;
	99	break;
	100	}
df561f66	101	fallthrough;
1da177e4 LT	102	case X25_FAC_THROUGHPUT:
	103	facilities->throughput = p[1];
	104	*vc_fac_mask \|= X25_MASK_THROUGHPUT;
	105	break;
a64b7b93 SP	106	case X25_MARKER:
a64b7b93 SP	107	break;
1da177e4	108	default:
b73e9e3c	109	pr_debug("unknown facility "
1da177e4 LT	110	"%02X, value %02X\n",
	111	p[0], p[1]);
	112	break;
	113	}
	114	p += 2;
	115	len -= 2;
	116	break;
	117	case X25_FAC_CLASS_B:
5ef41308	118	if (len < 3)
95c30430	119	return -1;
1da177e4 LT	120	switch (*p) {
	121	case X25_FAC_PACKET_SIZE:
	122	facilities->pacsize_in = p[1];
	123	facilities->pacsize_out = p[2];
	124	*vc_fac_mask \|= X25_MASK_PACKET_SIZE;
	125	break;
	126	case X25_FAC_WINDOW_SIZE:
	127	facilities->winsize_in = p[1];
	128	facilities->winsize_out = p[2];
	129	*vc_fac_mask \|= X25_MASK_WINDOW_SIZE;
	130	break;
	131	default:
b73e9e3c	132	pr_debug("unknown facility "
1da177e4 LT	133	"%02X, values %02X, %02X\n",
	134	p[0], p[1], p[2]);
	135	break;
	136	}
	137	p += 3;
	138	len -= 3;
	139	break;
	140	case X25_FAC_CLASS_C:
5ef41308	141	if (len < 4)
95c30430	142	return -1;
b73e9e3c	143	pr_debug("unknown facility %02X, "
1da177e4 LT	144	"values %02X, %02X, %02X\n",
	145	p[0], p[1], p[2], p[3]);
	146	p += 4;
	147	len -= 4;
	148	break;
	149	case X25_FAC_CLASS_D:
5ef41308	150	if (len < p[1] + 2)
95c30430	151	return -1;
a64b7b93	152	switch (*p) {
f8e1d201	153	case X25_FAC_CALLING_AE:
a6331d6f	154	if (p[1] > X25_MAX_DTE_FACIL_LEN \|\| p[1] <= 1)
95c30430	155	return -1;
80aa4e10 DC	156	if (p[2] > X25_MAX_AE_LEN)
80aa4e10 DC	157	return -1;
a64b7b93 SP	158	dte_facs->calling_len = p[2];
	159	memcpy(dte_facs->calling_ae, &p[3], p[1] - 1);
	160	*vc_fac_mask \|= X25_MASK_CALLING_AE;
	161	break;
	162	case X25_FAC_CALLED_AE:
a6331d6f	163	if (p[1] > X25_MAX_DTE_FACIL_LEN \|\| p[1] <= 1)
95c30430	164	return -1;
80aa4e10 DC	165	if (p[2] > X25_MAX_AE_LEN)
80aa4e10 DC	166	return -1;
a64b7b93 SP	167	dte_facs->called_len = p[2];
	168	memcpy(dte_facs->called_ae, &p[3], p[1] - 1);
	169	*vc_fac_mask \|= X25_MASK_CALLED_AE;
	170	break;
	171	default:
b73e9e3c	172	pr_debug("unknown facility %02X,"
5ef41308	173	"length %d\n", p[0], p[1]);
a64b7b93 SP	174	break;
a64b7b93 SP	175	}
1da177e4	176	len -= p[1] + 2;
a64b7b93	177	p += p[1] + 2;
1da177e4 LT	178	break;
	179	}
	180	}
	181
	182	return p - skb->data;
	183	}
	184
	185	/*
	186	* Create a set of facilities.
	187	*/
	188	int x25_create_facilities(unsigned char *buffer,
a64b7b93 SP	189	struct x25_facilities *facilities,
a64b7b93 SP	190	struct x25_dte_facilities *dte_facs, unsigned long facil_mask)
1da177e4 LT	191	{
	192	unsigned char *p = buffer + 1;
	193	int len;
	194
	195	if (!facil_mask) {
	196	/*
	197	* Length of the facilities field in call_req or
	198	* call_accept packets
	199	*/
	200	buffer[0] = 0;
	201	len = 1; /* 1 byte for the length field */
	202	return len;
	203	}
	204
	205	if (facilities->reverse && (facil_mask & X25_MASK_REVERSE)) {
	206	*p++ = X25_FAC_REVERSE;
ebc3f64b	207	*p++ = facilities->reverse;
1da177e4 LT	208	}
	209
	210	if (facilities->throughput && (facil_mask & X25_MASK_THROUGHPUT)) {
	211	*p++ = X25_FAC_THROUGHPUT;
	212	*p++ = facilities->throughput;
	213	}
	214
	215	if ((facilities->pacsize_in \|\| facilities->pacsize_out) &&
	216	(facil_mask & X25_MASK_PACKET_SIZE)) {
	217	*p++ = X25_FAC_PACKET_SIZE;
	218	*p++ = facilities->pacsize_in ? : facilities->pacsize_out;
	219	*p++ = facilities->pacsize_out ? : facilities->pacsize_in;
	220	}
	221
	222	if ((facilities->winsize_in \|\| facilities->winsize_out) &&
	223	(facil_mask & X25_MASK_WINDOW_SIZE)) {
	224	*p++ = X25_FAC_WINDOW_SIZE;
	225	*p++ = facilities->winsize_in ? : facilities->winsize_out;
	226	*p++ = facilities->winsize_out ? : facilities->winsize_in;
	227	}
	228
a64b7b93 SP	229	if (facil_mask & (X25_MASK_CALLING_AE\|X25_MASK_CALLED_AE)) {
	230	*p++ = X25_MARKER;
	231	*p++ = X25_DTE_SERVICES;
	232	}
	233
	234	if (dte_facs->calling_len && (facil_mask & X25_MASK_CALLING_AE)) {
95c96174	235	unsigned int bytecount = (dte_facs->calling_len + 1) >> 1;
a64b7b93 SP	236	*p++ = X25_FAC_CALLING_AE;
	237	*p++ = 1 + bytecount;
	238	*p++ = dte_facs->calling_len;
	239	memcpy(p, dte_facs->calling_ae, bytecount);
	240	p += bytecount;
	241	}
	242
	243	if (dte_facs->called_len && (facil_mask & X25_MASK_CALLED_AE)) {
95c96174	244	unsigned int bytecount = (dte_facs->called_len % 2) ?
a64b7b93 SP	245	dte_facs->called_len / 2 + 1 :
	246	dte_facs->called_len / 2;
	247	*p++ = X25_FAC_CALLED_AE;
	248	*p++ = 1 + bytecount;
	249	*p++ = dte_facs->called_len;
	250	memcpy(p, dte_facs->called_ae, bytecount);
	251	p+=bytecount;
	252	}
	253
1da177e4 LT	254	len = p - buffer;
	255	buffer[0] = len - 1;
	256
	257	return len;
	258	}
	259
	260	/*
	261	* Try to reach a compromise on a set of facilities.
	262	*
	263	* The only real problem is with reverse charging.
	264	*/
	265	int x25_negotiate_facilities(struct sk_buff skb, struct sock sk,
a64b7b93	266	struct x25_facilities new, struct x25_dte_facilities dte)
1da177e4 LT	267	{
	268	struct x25_sock *x25 = x25_sk(sk);
	269	struct x25_facilities *ours = &x25->facilities;
	270	struct x25_facilities theirs;
	271	int len;
	272
	273	memset(&theirs, 0, sizeof(theirs));
	274	memcpy(new, ours, sizeof(*new));
79e48650	275	memset(dte, 0, sizeof(*dte));
1da177e4	276
a64b7b93	277	len = x25_parse_facilities(skb, &theirs, dte, &x25->vc_facil_mask);
f5eb917b JH	278	if (len < 0)
f5eb917b JH	279	return len;
1da177e4 LT	280
	281	/*
	282	* They want reverse charging, we won't accept it.
	283	*/
ebc3f64b	284	if ((theirs.reverse & 0x01 ) && (ours->reverse & 0x01)) {
8e5443d2	285	net_dbg_ratelimited("X.25: rejecting reverse charging request\n");
1da177e4 LT	286	return -1;
	287	}
	288
	289	new->reverse = theirs.reverse;
	290
	291	if (theirs.throughput) {
ddd0451f JH	292	int theirs_in = theirs.throughput & 0x0f;
	293	int theirs_out = theirs.throughput & 0xf0;
	294	int ours_in = ours->throughput & 0x0f;
	295	int ours_out = ours->throughput & 0xf0;
	296	if (!ours_in \|\| theirs_in < ours_in) {
8e5443d2	297	net_dbg_ratelimited("X.25: inbound throughput negotiated\n");
ddd0451f JH	298	new->throughput = (new->throughput & 0xf0) \| theirs_in;
	299	}
	300	if (!ours_out \|\| theirs_out < ours_out) {
8e5443d2	301	net_dbg_ratelimited(
ddd0451f JH	302	"X.25: outbound throughput negotiated\n");
ddd0451f JH	303	new->throughput = (new->throughput & 0x0f) \| theirs_out;
1da177e4 LT	304	}
	305	}
	306
	307	if (theirs.pacsize_in && theirs.pacsize_out) {
	308	if (theirs.pacsize_in < ours->pacsize_in) {
8e5443d2	309	net_dbg_ratelimited("X.25: packet size inwards negotiated down\n");
1da177e4 LT	310	new->pacsize_in = theirs.pacsize_in;
	311	}
	312	if (theirs.pacsize_out < ours->pacsize_out) {
8e5443d2	313	net_dbg_ratelimited("X.25: packet size outwards negotiated down\n");
1da177e4 LT	314	new->pacsize_out = theirs.pacsize_out;
	315	}
	316	}
	317
	318	if (theirs.winsize_in && theirs.winsize_out) {
	319	if (theirs.winsize_in < ours->winsize_in) {
8e5443d2	320	net_dbg_ratelimited("X.25: window size inwards negotiated down\n");
1da177e4 LT	321	new->winsize_in = theirs.winsize_in;
	322	}
	323	if (theirs.winsize_out < ours->winsize_out) {
8e5443d2	324	net_dbg_ratelimited("X.25: window size outwards negotiated down\n");
1da177e4 LT	325	new->winsize_out = theirs.winsize_out;
	326	}
	327	}
	328
	329	return len;
	330	}
	331
	332	/*
f8e1d201	333	* Limit values of certain facilities according to the capability of the
1da177e4 LT	334	* currently attached x25 link.
	335	*/
	336	void x25_limit_facilities(struct x25_facilities *facilities,
	337	struct x25_neigh *nb)
	338	{
	339
	340	if (!nb->extended) {
	341	if (facilities->winsize_in > 7) {
b73e9e3c	342	pr_debug("incoming winsize limited to 7\n");
1da177e4 LT	343	facilities->winsize_in = 7;
	344	}
	345	if (facilities->winsize_out > 7) {
	346	facilities->winsize_out = 7;
b73e9e3c	347	pr_debug("outgoing winsize limited to 7\n");
1da177e4 LT	348	}
	349	}
	350	}