net/llc/*.c

Forward port of LLC from 2.4 to 2.5. This is the forward port of the LLC stack
released by Procom Inc. for Linux 2.0.30, I have heavily modified it to make
it similar to other Linux network stacks, using of struct sk_buff to represent
in-transit packets and doing massive code cleanups.

Jay Schullist contributed support for BSD Sockets, as the original code had
only a simple in kernel API for use by upper layer protocols, such as the
NetBEUI stack also provided by Procom for 2.0.30.

This code is basically what I had previously submitted to Alan Cox for his
2.4-ac series and that is even shipped in source form, in the Red Hat 7.3
kernel package, plus cleanups wrt standard syntax for labeled elements and
further use of this C construct to make the code more resilient to editing
mistakes, using the compiler to further check the source code.

TODO:

Make it completely SMP safe, as the reports of successful usage up to now and
the testing is done on UP.

Completely remove the old LLC code in the kernel, that is still there for things
like Appletalk, IPX, etc to use, also check that all these protocols work
correctly with this new LLC stack.

This code is already being used in the linux-sna project and Jay Schullist
has been developing support for things like DLSw and other protocols that works
on top of 802.2.

I'll be releasing patches with the NetBEUI stack and updated samba-2.0.6 patches
for use with NetBEUI and this LLC stack in the future. But the NetBEUI code
is available already in my kernel.org ftp area at:

ftp://ftp.kernel.org/pub/linux/kernel/people/acme.

Please report problems to me or the linux-sna mailing list, instructions on how
to subscribe are available at http://www.linux-sna.org website.

1 files changed, 102 insertions, 0 deletions

diff --git a/include/linux/llc.h b/include/linux/llc.h
new file mode 100644
index 000000000000..824a149e9e6b
--- /dev/null
+++ b/include/linux/llc.h
@@ -0,0 +1,102 @@
+#ifndef __LINUX_LLC_H
+#define __LINUX_LLC_H
+/*
+ * IEEE 802.2 User Interface SAPs for Linux, data structures and indicators.
+ *
+ * Copyright (c) 2001 by Jay Schulist <jschlst@samba.org>
+ *
+ * This program can be redistributed or modified under the terms of the
+ * GNU General Public License as published by the Free Software Foundation.
+ * This program is distributed without any warranty or implied warranty
+ * of merchantability or fitness for a particular purpose.
+ *
+ * See the GNU General Public License for more details.
+ */
+#define __LLC_SOCK_SIZE__ 28	/* sizeof(sockaddr_llc), word align. */
+struct sockaddr_llc {
+	sa_family_t     sllc_family;	/* AF_LLC */
+	sa_family_t	sllc_arphrd;	/* ARPHRD_ETHER */
+	unsigned char   sllc_test;
+	unsigned char   sllc_xid;
+	unsigned char	sllc_ua;	/* UA data, only for SOCK_STREAM. */
+	unsigned char   sllc_dsap;
+	unsigned char   sllc_ssap;
+	unsigned char   sllc_dmac[IFHWADDRLEN];
+	unsigned char   sllc_smac[IFHWADDRLEN];
+	unsigned char   sllc_mmac[IFHWADDRLEN];
+	unsigned char   __pad[__LLC_SOCK_SIZE__ - sizeof(sa_family_t) * 2 -
+			      sizeof(unsigned char) * 5 - IFHWADDRLEN * 3];
+};
+
+/* sockopt definitions. */
+enum llc_sockopts {
+	LLC_OPT_UNKNOWN = 0,
+	LLC_OPT_RETRY,		/* max retrans attempts. */
+	LLC_OPT_SIZE,		/* max PDU size (octets). */
+	LLC_OPT_ACK_TMR_EXP,	/* ack expire time (secs). */
+	LLC_OPT_P_TMR_EXP,	/* pf cycle expire time (secs). */
+	LLC_OPT_REJ_TMR_EXP,	/* rej sent expire time (secs). */
+	LLC_OPT_BUSY_TMR_EXP,	/* busy state expire time (secs). */
+	LLC_OPT_TX_WIN,		/* tx window size. */
+	LLC_OPT_RX_WIN,		/* rx window size. */
+	LLC_OPT_MAX
+};
+
+#define LLC_OPT_MAX_RETRY	 100
+#define LLC_OPT_MAX_SIZE	4196
+#define LLC_OPT_MAX_WIN		 127
+#define LLC_OPT_MAX_ACK_TMR_EXP	  60
+#define LLC_OPT_MAX_P_TMR_EXP	  60
+#define LLC_OPT_MAX_REJ_TMR_EXP	  60
+#define LLC_OPT_MAX_BUSY_TMR_EXP  60
+
+/* LLC SAP types. */
+#define LLC_SAP_NULL	0x00		/* NULL SAP. 			*/
+#define LLC_SAP_LLC	0x02		/* LLC Sublayer Managment. 	*/
+#define LLC_SAP_SNA	0x04		/* SNA Path Control. 		*/
+#define LLC_SAP_PNM	0x0E		/* Proway Network Managment.	*/	
+#define LLC_SAP_IP	0x06		/* TCP/IP. 			*/
+#define LLC_SAP_BSPAN	0x42		/* Bridge Spanning Tree Proto	*/
+#define LLC_SAP_MMS	0x4E		/* Manufacturing Message Srv.	*/
+#define LLC_SAP_8208	0x7E		/* ISO 8208			*/
+#define LLC_SAP_3COM	0x80		/* 3COM. 			*/
+#define LLC_SAP_PRO	0x8E		/* Proway Active Station List	*/
+#define LLC_SAP_SNAP	0xAA		/* SNAP. 			*/
+#define LLC_SAP_BANYAN	0xBC		/* Banyan. 			*/
+#define LLC_SAP_IPX	0xE0		/* IPX/SPX. 			*/
+#define LLC_SAP_NETBEUI	0xF0		/* NetBEUI. 			*/
+#define LLC_SAP_LANMGR	0xF4		/* LanManager. 			*/
+#define LLC_SAP_IMPL	0xF8		/* IMPL				*/
+#define LLC_SAP_DISC	0xFC		/* Discovery			*/
+#define LLC_SAP_OSI	0xFE		/* OSI Network Layers. 		*/
+#define LLC_SAP_LAR	0xDC		/* LAN Address Resolution 	*/
+#define LLC_SAP_RM	0xD4		/* Resource Management 		*/
+#define LLC_SAP_GLOBAL	0xFF		/* Global SAP. 			*/
+
+#ifdef __KERNEL__
+#define LLC_SAP_DYN_START	0xC0
+#define LLC_SAP_DYN_STOP	0xDE
+#define LLC_SAP_DYN_TRIES	4
+
+struct sock;
+
+struct llc_ui_opt {
+	u16		     link;	/* network layer link number */
+	struct llc_sap	    *sap;	/* pointer to parent SAP */
+	struct sock	    *core_sk;
+	struct net_device   *dev;	/* device to send to remote */
+	struct sockaddr_llc  addr;	/* address sock is bound to */
+};
+
+#define llc_ui_sk(__sk) ((struct llc_ui_opt *)(__sk)->protinfo)
+#define llc_ui_skb_cb(__skb) ((struct sockaddr_llc *)&((__skb)->cb[0]))
+
+#ifdef CONFIG_LLC_UI
+extern int llc_ui_init(void);
+extern void llc_ui_exit(void);
+#else
+#define llc_ui_init()
+#define llc_ui_exit()
+#endif
+#endif /* __KERNEL__ */
+#endif /* __LINUX_LLC_H */