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Diffstat (limited to 'net/irda/irnet/irnet.h')
| -rw-r--r-- | net/irda/irnet/irnet.h | 523 |
1 files changed, 523 insertions, 0 deletions
diff --git a/net/irda/irnet/irnet.h b/net/irda/irnet/irnet.h new file mode 100644 index 000000000..8d65bb947 --- /dev/null +++ b/net/irda/irnet/irnet.h @@ -0,0 +1,523 @@ +/* + * IrNET protocol module : Synchronous PPP over an IrDA socket. + * + * Jean II - HPL `00 - <jt@hpl.hp.com> + * + * This file contains definitions and declarations global to the IrNET module, + * all grouped in one place... + * This file is a *private* header, so other modules don't want to know + * what's in there... + * + * Note : as most part of the Linux kernel, this module is available + * under the GNU General Public License (GPL). + */ + +#ifndef IRNET_H +#define IRNET_H + +/************************** DOCUMENTATION ***************************/ +/* + * What is IrNET + * ------------- + * IrNET is a protocol allowing to carry TCP/IP traffic between two + * IrDA peers in an efficient fashion. It is a thin layer, passing PPP + * packets to IrTTP and vice versa. It uses PPP in synchronous mode, + * because IrTTP offer a reliable sequenced packet service (as opposed + * to a byte stream). In fact, you could see IrNET as carrying TCP/IP + * in a IrDA socket, using PPP to provide the glue. + * + * The main difference with traditional PPP over IrCOMM is that we + * avoid the framing and serial emulation which are a performance + * bottleneck. It also allows multipoint communications in a sensible + * fashion. + * + * The main difference with IrLAN is that we use PPP for the link + * management, which is more standard, interoperable and flexible than + * the IrLAN protocol. For example, PPP adds authentication, + * encryption, compression, header compression and automated routing + * setup. And, as IrNET let PPP do the hard work, the implementation + * is much simpler than IrLAN. + * + * The Linux implementation + * ------------------------ + * IrNET is written on top of the Linux-IrDA stack, and interface with + * the generic Linux PPP driver. Because IrNET depend on recent + * changes of the PPP driver interface, IrNET will work only with very + * recent kernel (2.3.99-pre6 and up). + * + * The present implementation offer the following features : + * o simple user interface using pppd + * o efficient implementation (interface directly to PPP and IrTTP) + * o addressing (you can specify the name of the IrNET recipient) + * o multipoint operation (limited by IrLAP specification) + * o information in /proc/net/irda/irnet + * o IrNET events on /dev/irnet (for user space daemon) + * o IrNET daemon (irnetd) to automatically handle incoming requests + * o Windows 2000 compatibility (tested, but need more work) + * Currently missing : + * o Lot's of testing (that's your job) + * o Connection retries (may be too hard to do) + * o Check pppd persist mode + * o User space daemon (to automatically handle incoming requests) + * + * The setup is not currently the most easy, but this should get much + * better when everything will get integrated... + * + * Acknowledgements + * ---------------- + * This module is based on : + * o The PPP driver (ppp_synctty/ppp_generic) by Paul Mackerras + * o The IrLAN protocol (irlan_common/XXX) by Dag Brattli + * o The IrSock interface (af_irda) by Dag Brattli + * o Some other bits from the kernel and my drivers... + * Infinite thanks to those brave souls for providing the infrastructure + * upon which IrNET is built. + * + * Thanks to all my colleagues in HP for helping me. In particular, + * thanks to Salil Pradhan and Bill Serra for W2k testing... + * Thanks to Luiz Magalhaes for irnetd and much testing... + * + * Thanks to Alan Cox for answering lot's of my stupid questions, and + * to Paul Mackerras answering my questions on how to best integrate + * IrNET and pppd. + * + * Jean II + * + * Note on some implementations choices... + * ------------------------------------ + * 1) Direct interface vs tty/socket + * I could have used a tty interface to hook to ppp and use the full + * socket API to connect to IrDA. The code would have been easier to + * maintain, and maybe the code would have been smaller... + * Instead, we hook directly to ppp_generic and to IrTTP, which make + * things more complicated... + * + * The first reason is flexibility : this allow us to create IrNET + * instances on demand (no /dev/ircommX crap) and to allow linkname + * specification on pppd command line... + * + * Second reason is speed optimisation. If you look closely at the + * transmit and receive paths, you will notice that they are "super lean" + * (that's why they look ugly), with no function calls and as little data + * copy and modification as I could... + * + * 2) irnetd in user space + * irnetd is implemented in user space, which is necessary to call pppd. + * This also give maximum benefits in term of flexibility and customability, + * and allow to offer the event channel, useful for other stuff like debug. + * + * On the other hand, this require a loose coordination between the + * present module and irnetd. One critical area is how incoming request + * are handled. + * When irnet receive an incoming request, it send an event to irnetd and + * drop the incoming IrNET socket. + * irnetd start a pppd instance, which create a new IrNET socket. This new + * socket is then connected in the originating node to the pppd instance. + * At this point, in the originating node, the first socket is closed. + * + * I admit, this is a bit messy and waste some resources. The alternative + * is caching incoming socket, and that's also quite messy and waste + * resources. + * We also make connection time slower. For example, on a 115 kb/s link it + * adds 60ms to the connection time (770 ms). However, this is slower than + * the time it takes to fire up pppd on my P133... + * + * + * History : + * ------- + * + * v1 - 15.5.00 - Jean II + * o Basic IrNET (hook to ppp_generic & IrTTP - incl. multipoint) + * o control channel on /dev/irnet (set name/address) + * o event channel on /dev/irnet (for user space daemon) + * + * v2 - 5.6.00 - Jean II + * o Enable DROP_NOT_READY to avoid PPP timeouts & other weirdness... + * o Add DISCONNECT_TO event and rename DISCONNECT_FROM. + * o Set official device number alloaction on /dev/irnet + * + * v3 - 30.8.00 - Jean II + * o Update to latest Linux-IrDA changes : + * - queue_t => irda_queue_t + * o Update to ppp-2.4.0 : + * - move irda_irnet_connect from PPPIOCATTACH to TIOCSETD + * o Add EXPIRE event (depend on new IrDA-Linux patch) + * o Switch from `hashbin_remove' to `hashbin_remove_this' to fix + * a multilink bug... (depend on new IrDA-Linux patch) + * o fix a self->daddr to self->raddr in irda_irnet_connect to fix + * another multilink bug (darn !) + * o Remove LINKNAME_IOCTL cruft + * + * v3b - 31.8.00 - Jean II + * o Dump discovery log at event channel startup + * + * v4 - 28.9.00 - Jean II + * o Fix interaction between poll/select and dump discovery log + * o Add IRNET_BLOCKED_LINK event (depend on new IrDA-Linux patch) + * o Add IRNET_NOANSWER_FROM event (mostly to help support) + * o Release flow control in disconnect_indication + * o Block packets while connecting (speed up connections) + * + * v5 - 11.01.01 - Jean II + * o Init self->max_header_size, just in case... + * o Set up ap->chan.hdrlen, to get zero copy on tx side working. + * o avoid tx->ttp->flow->ppp->tx->... loop, by checking flow state + * Thanks to Christian Gennerat for finding this bug ! + * --- + * o Declare the proper MTU/MRU that we can support + * (but PPP doesn't read the MTU value :-() + * o Declare hashbin HB_NOLOCK instead of HB_LOCAL to avoid + * disabling and enabling irq twice + * + * v6 - 31.05.01 - Jean II + * o Print source address in Found, Discovery, Expiry & Request events + * o Print requested source address in /proc/net/irnet + * o Change control channel input. Allow multiple commands in one line. + * o Add saddr command to change ap->rsaddr (and use that in IrDA) + * --- + * o Make the IrDA connection procedure totally asynchronous. + * Heavy rewrite of the IAS query code and the whole connection + * procedure. Now, irnet_connect() no longer need to be called from + * a process context... + * o Enable IrDA connect retries in ppp_irnet_send(). The good thing + * is that IrDA connect retries are directly driven by PPP LCP + * retries (we retry for each LCP packet), so that everything + * is transparently controlled from pppd lcp-max-configure. + * o Add ttp_connect flag to prevent rentry on the connect procedure + * o Test and fixups to eliminate side effects of retries + * + * v7 - 22.08.01 - Jean II + * o Cleanup : Change "saddr = 0x0" to "saddr = DEV_ADDR_ANY" + * o Fix bug in BLOCK_WHEN_CONNECT introduced in v6 : due to the + * asynchronous IAS query, self->tsap is NULL when PPP send the + * first packet. This was preventing "connect-delay 0" to work. + * Change the test in ppp_irnet_send() to self->ttp_connect. + * + * v8 - 1.11.01 - Jean II + * o Tighten the use of self->ttp_connect and self->ttp_open to + * prevent various race conditions. + * o Avoid leaking discovery log and skb + * o Replace "self" with "server" in irnet_connect_indication() to + * better detect cut'n'paste error ;-) + * + * v9 - 29.11.01 - Jean II + * o Fix event generation in disconnect indication that I broke in v8 + * It was always generation "No-Answer" because I was testing ttp_open + * just after clearing it. *blush*. + * o Use newly created irttp_listen() to fix potential crash when LAP + * destroyed before irnet module removed. + * + * v10 - 4.3.2 - Jean II + * o When receiving a disconnect indication, don't reenable the + * PPP Tx queue, this will trigger a reconnect. Instead, close + * the channel, which will kill pppd... + * + * v11 - 20.3.02 - Jean II + * o Oops ! v10 fix disabled IrNET retries and passive behaviour. + * Better fix in irnet_disconnect_indication() : + * - if connected, kill pppd via hangup. + * - if not connected, reenable ppp Tx, which trigger IrNET retry. + * + * v12 - 10.4.02 - Jean II + * o Fix race condition in irnet_connect_indication(). + * If the socket was already trying to connect, drop old connection + * and use new one only if acting as primary. See comments. + * + * v13 - 30.5.02 - Jean II + * o Update module init code + * + * v14 - 20.2.03 - Jean II + * o Add discovery hint bits in the control channel. + * o Remove obsolete MOD_INC/DEC_USE_COUNT in favor of .owner + * + * v15 - 7.4.03 - Jean II + * o Replace spin_lock_irqsave() with spin_lock_bh() so that we can + * use ppp_unit_number(). It's probably also better overall... + * o Disable call to ppp_unregister_channel(), because we can't do it. + */ + +/***************************** INCLUDES *****************************/ + +#include <linux/module.h> + +#include <linux/kernel.h> +#include <linux/skbuff.h> +#include <linux/tty.h> +#include <linux/proc_fs.h> +#include <linux/netdevice.h> +#include <linux/miscdevice.h> +#include <linux/poll.h> +#include <linux/capability.h> +#include <linux/ctype.h> /* isspace() */ +#include <linux/string.h> /* skip_spaces() */ +#include <asm/uaccess.h> +#include <linux/init.h> + +#include <linux/ppp_defs.h> +#include <linux/ppp-ioctl.h> +#include <linux/ppp_channel.h> + +#include <net/irda/irda.h> +#include <net/irda/iriap.h> +#include <net/irda/irias_object.h> +#include <net/irda/irlmp.h> +#include <net/irda/irttp.h> +#include <net/irda/discovery.h> + +/***************************** OPTIONS *****************************/ +/* + * Define or undefine to compile or not some optional part of the + * IrNET driver... + * Note : the present defaults make sense, play with that at your + * own risk... + */ +/* IrDA side of the business... */ +#define DISCOVERY_NOMASK /* To enable W2k compatibility... */ +#define ADVERTISE_HINT /* Advertise IrLAN hint bit */ +#define ALLOW_SIMULT_CONNECT /* This seem to work, cross fingers... */ +#define DISCOVERY_EVENTS /* Query the discovery log to post events */ +#define INITIAL_DISCOVERY /* Dump current discovery log as events */ +#undef STREAM_COMPAT /* Not needed - potentially messy */ +#undef CONNECT_INDIC_KICK /* Might mess IrDA, not needed */ +#undef FAIL_SEND_DISCONNECT /* Might mess IrDA, not needed */ +#undef PASS_CONNECT_PACKETS /* Not needed ? Safe */ +#undef MISSING_PPP_API /* Stuff I wish I could do */ + +/* PPP side of the business */ +#define BLOCK_WHEN_CONNECT /* Block packets when connecting */ +#define CONNECT_IN_SEND /* Retry IrDA connection procedure */ +#undef FLUSH_TO_PPP /* Not sure about this one, let's play safe */ +#undef SECURE_DEVIRNET /* Bah... */ + +/****************************** DEBUG ******************************/ + +/* + * This set of flags enable and disable all the various warning, + * error and debug message of this driver. + * Each section can be enabled and disabled independently + */ +/* In the PPP part */ +#define DEBUG_CTRL_TRACE 0 /* Control channel */ +#define DEBUG_CTRL_INFO 0 /* various info */ +#define DEBUG_CTRL_ERROR 1 /* problems */ +#define DEBUG_FS_TRACE 0 /* filesystem callbacks */ +#define DEBUG_FS_INFO 0 /* various info */ +#define DEBUG_FS_ERROR 1 /* problems */ +#define DEBUG_PPP_TRACE 0 /* PPP related functions */ +#define DEBUG_PPP_INFO 0 /* various info */ +#define DEBUG_PPP_ERROR 1 /* problems */ +#define DEBUG_MODULE_TRACE 0 /* module insertion/removal */ +#define DEBUG_MODULE_ERROR 1 /* problems */ + +/* In the IrDA part */ +#define DEBUG_IRDA_SR_TRACE 0 /* IRDA subroutines */ +#define DEBUG_IRDA_SR_INFO 0 /* various info */ +#define DEBUG_IRDA_SR_ERROR 1 /* problems */ +#define DEBUG_IRDA_SOCK_TRACE 0 /* IRDA main socket functions */ +#define DEBUG_IRDA_SOCK_INFO 0 /* various info */ +#define DEBUG_IRDA_SOCK_ERROR 1 /* problems */ +#define DEBUG_IRDA_SERV_TRACE 0 /* The IrNET server */ +#define DEBUG_IRDA_SERV_INFO 0 /* various info */ +#define DEBUG_IRDA_SERV_ERROR 1 /* problems */ +#define DEBUG_IRDA_TCB_TRACE 0 /* IRDA IrTTP callbacks */ +#define DEBUG_IRDA_CB_INFO 0 /* various info */ +#define DEBUG_IRDA_CB_ERROR 1 /* problems */ +#define DEBUG_IRDA_OCB_TRACE 0 /* IRDA other callbacks */ +#define DEBUG_IRDA_OCB_INFO 0 /* various info */ +#define DEBUG_IRDA_OCB_ERROR 1 /* problems */ + +#define DEBUG_ASSERT 0 /* Verify all assertions */ + +/* + * These are the macros we are using to actually print the debug + * statements. Don't look at it, it's ugly... + * + * One of the trick is that, as the DEBUG_XXX are constant, the + * compiler will optimise away the if() in all cases. + */ +/* All error messages (will show up in the normal logs) */ +#define DERROR(dbg, format, args...) \ + {if(DEBUG_##dbg) \ + printk(KERN_INFO "irnet: %s(): " format, __func__ , ##args);} + +/* Normal debug message (will show up in /var/log/debug) */ +#define DEBUG(dbg, format, args...) \ + {if(DEBUG_##dbg) \ + printk(KERN_DEBUG "irnet: %s(): " format, __func__ , ##args);} + +/* Entering a function (trace) */ +#define DENTER(dbg, format, args...) \ + {if(DEBUG_##dbg) \ + printk(KERN_DEBUG "irnet: -> %s" format, __func__ , ##args);} + +/* Entering and exiting a function in one go (trace) */ +#define DPASS(dbg, format, args...) \ + {if(DEBUG_##dbg) \ + printk(KERN_DEBUG "irnet: <>%s" format, __func__ , ##args);} + +/* Exiting a function (trace) */ +#define DEXIT(dbg, format, args...) \ + {if(DEBUG_##dbg) \ + printk(KERN_DEBUG "irnet: <-%s()" format, __func__ , ##args);} + +/* Exit a function with debug */ +#define DRETURN(ret, dbg, args...) \ + {DEXIT(dbg, ": " args);\ + return ret; } + +/* Exit a function on failed condition */ +#define DABORT(cond, ret, dbg, args...) \ + {if(cond) {\ + DERROR(dbg, args);\ + return ret; }} + +/* Invalid assertion, print out an error and exit... */ +#define DASSERT(cond, ret, dbg, args...) \ + {if((DEBUG_ASSERT) && !(cond)) {\ + DERROR(dbg, "Invalid assertion: " args);\ + return ret; }} + +/************************ CONSTANTS & MACROS ************************/ + +/* Paranoia */ +#define IRNET_MAGIC 0xB00754 + +/* Number of control events in the control channel buffer... */ +#define IRNET_MAX_EVENTS 8 /* Should be more than enough... */ + +/****************************** TYPES ******************************/ + +/* + * This is the main structure where we store all the data pertaining to + * one instance of irnet. + * Note : in irnet functions, a pointer this structure is usually called + * "ap" or "self". If the code is borrowed from the IrDA stack, it tend + * to be called "self", and if it is borrowed from the PPP driver it is + * "ap". Apart from that, it's exactly the same structure ;-) + */ +typedef struct irnet_socket +{ + /* ------------------- Instance management ------------------- */ + /* We manage a linked list of IrNET socket instances */ + irda_queue_t q; /* Must be first - for hasbin */ + int magic; /* Paranoia */ + + /* --------------------- FileSystem part --------------------- */ + /* "pppd" interact directly with us on a /dev/ file */ + struct file * file; /* File descriptor of this instance */ + /* TTY stuff - to keep "pppd" happy */ + struct ktermios termios; /* Various tty flags */ + /* Stuff for the control channel */ + int event_index; /* Last read in the event log */ + + /* ------------------------- PPP part ------------------------- */ + /* We interface directly to the ppp_generic driver in the kernel */ + int ppp_open; /* registered with ppp_generic */ + struct ppp_channel chan; /* Interface to generic ppp layer */ + + int mru; /* Max size of PPP payload */ + u32 xaccm[8]; /* Asynchronous character map (just */ + u32 raccm; /* to please pppd - dummy) */ + unsigned int flags; /* PPP flags (compression, ...) */ + unsigned int rbits; /* Unused receive flags ??? */ + struct work_struct disconnect_work; /* Process context disconnection */ + /* ------------------------ IrTTP part ------------------------ */ + /* We create a pseudo "socket" over the IrDA tranport */ + unsigned long ttp_open; /* Set when IrTTP is ready */ + unsigned long ttp_connect; /* Set when IrTTP is connecting */ + struct tsap_cb * tsap; /* IrTTP instance (the connection) */ + + char rname[NICKNAME_MAX_LEN + 1]; + /* IrDA nickname of destination */ + __u32 rdaddr; /* Requested peer IrDA address */ + __u32 rsaddr; /* Requested local IrDA address */ + __u32 daddr; /* actual peer IrDA address */ + __u32 saddr; /* my local IrDA address */ + __u8 dtsap_sel; /* Remote TSAP selector */ + __u8 stsap_sel; /* Local TSAP selector */ + + __u32 max_sdu_size_rx;/* Socket parameters used for IrTTP */ + __u32 max_sdu_size_tx; + __u32 max_data_size; + __u8 max_header_size; + LOCAL_FLOW tx_flow; /* State of the Tx path in IrTTP */ + + /* ------------------- IrLMP and IrIAS part ------------------- */ + /* Used for IrDA Discovery and socket name resolution */ + void * ckey; /* IrLMP client handle */ + __u16 mask; /* Hint bits mask (filter discov.)*/ + int nslots; /* Number of slots for discovery */ + + struct iriap_cb * iriap; /* Used to query remote IAS */ + int errno; /* status of the IAS query */ + + /* -------------------- Discovery log part -------------------- */ + /* Used by initial discovery on the control channel + * and by irnet_discover_daddr_and_lsap_sel() */ + struct irda_device_info *discoveries; /* Copy of the discovery log */ + int disco_index; /* Last read in the discovery log */ + int disco_number; /* Size of the discovery log */ + + struct mutex lock; + +} irnet_socket; + +/* + * This is the various event that we will generate on the control channel + */ +typedef enum irnet_event +{ + IRNET_DISCOVER, /* New IrNET node discovered */ + IRNET_EXPIRE, /* IrNET node expired */ + IRNET_CONNECT_TO, /* IrNET socket has connected to other node */ + IRNET_CONNECT_FROM, /* Other node has connected to IrNET socket */ + IRNET_REQUEST_FROM, /* Non satisfied connection request */ + IRNET_NOANSWER_FROM, /* Failed connection request */ + IRNET_BLOCKED_LINK, /* Link (IrLAP) is blocked for > 3s */ + IRNET_DISCONNECT_FROM, /* IrNET socket has disconnected */ + IRNET_DISCONNECT_TO /* Closing IrNET socket */ +} irnet_event; + +/* + * This is the storage for an event and its arguments + */ +typedef struct irnet_log +{ + irnet_event event; + int unit; + __u32 saddr; + __u32 daddr; + char name[NICKNAME_MAX_LEN + 1]; /* 21 + 1 */ + __u16_host_order hints; /* Discovery hint bits */ +} irnet_log; + +/* + * This is the storage for all events and related stuff... + */ +typedef struct irnet_ctrl_channel +{ + irnet_log log[IRNET_MAX_EVENTS]; /* Event log */ + int index; /* Current index in log */ + spinlock_t spinlock; /* Serialize access to the event log */ + wait_queue_head_t rwait; /* processes blocked on read (or poll) */ +} irnet_ctrl_channel; + +/**************************** PROTOTYPES ****************************/ +/* + * Global functions of the IrNET module + * Note : we list here also functions called from one file to the other. + */ + +/* -------------------------- IRDA PART -------------------------- */ +int irda_irnet_create(irnet_socket *); /* Initialise an IrNET socket */ +int irda_irnet_connect(irnet_socket *); /* Try to connect over IrDA */ +void irda_irnet_destroy(irnet_socket *); /* Teardown an IrNET socket */ +int irda_irnet_init(void); /* Initialise IrDA part of IrNET */ +void irda_irnet_cleanup(void); /* Teardown IrDA part of IrNET */ + +/**************************** VARIABLES ****************************/ + +/* Control channel stuff - allocated in irnet_irda.h */ +extern struct irnet_ctrl_channel irnet_events; + +#endif /* IRNET_H */ |