linux/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) …

#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)
{ … }

/*
 *	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)
{ … }

/*
 *	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)
{ … }

/*
 *	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)
{ … }