1 /* 2 * IrNET protocol module : Synchronous PPP over an IrDA socket. 3 * 4 * Jean II - HPL `00 - <jt@hpl.hp.com> 5 * 6 * This file contains definitions and declarations global to the IrNET module, 7 * all grouped in one place... 8 * This file is a *private* header, so other modules don't want to know 9 * what's in there... 10 * 11 * Note : as most part of the Linux kernel, this module is available 12 * under the GNU General Public License (GPL). 13 */ 14 15 #ifndef IRNET_H 16 #define IRNET_H 17 18 /************************** DOCUMENTATION ***************************/ 19 /* 20 * What is IrNET 21 * ------------- 22 * IrNET is a protocol allowing to carry TCP/IP traffic between two 23 * IrDA peers in an efficient fashion. It is a thin layer, passing PPP 24 * packets to IrTTP and vice versa. It uses PPP in synchronous mode, 25 * because IrTTP offer a reliable sequenced packet service (as opposed 26 * to a byte stream). In fact, you could see IrNET as carrying TCP/IP 27 * in a IrDA socket, using PPP to provide the glue. 28 * 29 * The main difference with traditional PPP over IrCOMM is that we 30 * avoid the framing and serial emulation which are a performance 31 * bottleneck. It also allows multipoint communications in a sensible 32 * fashion. 33 * 34 * The main difference with IrLAN is that we use PPP for the link 35 * management, which is more standard, interoperable and flexible than 36 * the IrLAN protocol. For example, PPP adds authentication, 37 * encryption, compression, header compression and automated routing 38 * setup. And, as IrNET let PPP do the hard work, the implementation 39 * is much simpler than IrLAN. 40 * 41 * The Linux implementation 42 * ------------------------ 43 * IrNET is written on top of the Linux-IrDA stack, and interface with 44 * the generic Linux PPP driver. Because IrNET depend on recent 45 * changes of the PPP driver interface, IrNET will work only with very 46 * recent kernel (2.3.99-pre6 and up). 47 * 48 * The present implementation offer the following features : 49 * o simple user interface using pppd 50 * o efficient implementation (interface directly to PPP and IrTTP) 51 * o addressing (you can specify the name of the IrNET recipient) 52 * o multipoint operation (limited by IrLAP specification) 53 * o information in /proc/net/irda/irnet 54 * o IrNET events on /dev/irnet (for user space daemon) 55 * o IrNET daemon (irnetd) to automatically handle incoming requests 56 * o Windows 2000 compatibility (tested, but need more work) 57 * Currently missing : 58 * o Lot's of testing (that's your job) 59 * o Connection retries (may be too hard to do) 60 * o Check pppd persist mode 61 * o User space daemon (to automatically handle incoming requests) 62 * 63 * The setup is not currently the most easy, but this should get much 64 * better when everything will get integrated... 65 * 66 * Acknowledgements 67 * ---------------- 68 * This module is based on : 69 * o The PPP driver (ppp_synctty/ppp_generic) by Paul Mackerras 70 * o The IrLAN protocol (irlan_common/XXX) by Dag Brattli 71 * o The IrSock interface (af_irda) by Dag Brattli 72 * o Some other bits from the kernel and my drivers... 73 * Infinite thanks to those brave souls for providing the infrastructure 74 * upon which IrNET is built. 75 * 76 * Thanks to all my colleagues in HP for helping me. In particular, 77 * thanks to Salil Pradhan and Bill Serra for W2k testing... 78 * Thanks to Luiz Magalhaes for irnetd and much testing... 79 * 80 * Thanks to Alan Cox for answering lot's of my stupid questions, and 81 * to Paul Mackerras answering my questions on how to best integrate 82 * IrNET and pppd. 83 * 84 * Jean II 85 * 86 * Note on some implementations choices... 87 * ------------------------------------ 88 * 1) Direct interface vs tty/socket 89 * I could have used a tty interface to hook to ppp and use the full 90 * socket API to connect to IrDA. The code would have been easier to 91 * maintain, and maybe the code would have been smaller... 92 * Instead, we hook directly to ppp_generic and to IrTTP, which make 93 * things more complicated... 94 * 95 * The first reason is flexibility : this allow us to create IrNET 96 * instances on demand (no /dev/ircommX crap) and to allow linkname 97 * specification on pppd command line... 98 * 99 * Second reason is speed optimisation. If you look closely at the 100 * transmit and receive paths, you will notice that they are "super lean" 101 * (that's why they look ugly), with no function calls and as little data 102 * copy and modification as I could... 103 * 104 * 2) irnetd in user space 105 * irnetd is implemented in user space, which is necessary to call pppd. 106 * This also give maximum benefits in term of flexibility and customability, 107 * and allow to offer the event channel, useful for other stuff like debug. 108 * 109 * On the other hand, this require a loose coordination between the 110 * present module and irnetd. One critical area is how incoming request 111 * are handled. 112 * When irnet receive an incoming request, it send an event to irnetd and 113 * drop the incoming IrNET socket. 114 * irnetd start a pppd instance, which create a new IrNET socket. This new 115 * socket is then connected in the originating node to the pppd instance. 116 * At this point, in the originating node, the first socket is closed. 117 * 118 * I admit, this is a bit messy and waste some resources. The alternative 119 * is caching incoming socket, and that's also quite messy and waste 120 * resources. 121 * We also make connection time slower. For example, on a 115 kb/s link it 122 * adds 60ms to the connection time (770 ms). However, this is slower than 123 * the time it takes to fire up pppd on my P133... 124 * 125 * 126 * History : 127 * ------- 128 * 129 * v1 - 15.5.00 - Jean II 130 * o Basic IrNET (hook to ppp_generic & IrTTP - incl. multipoint) 131 * o control channel on /dev/irnet (set name/address) 132 * o event channel on /dev/irnet (for user space daemon) 133 * 134 * v2 - 5.6.00 - Jean II 135 * o Enable DROP_NOT_READY to avoid PPP timeouts & other weirdness... 136 * o Add DISCONNECT_TO event and rename DISCONNECT_FROM. 137 * o Set official device number alloaction on /dev/irnet 138 * 139 * v3 - 30.8.00 - Jean II 140 * o Update to latest Linux-IrDA changes : 141 * - queue_t => irda_queue_t 142 * o Update to ppp-2.4.0 : 143 * - move irda_irnet_connect from PPPIOCATTACH to TIOCSETD 144 * o Add EXPIRE event (depend on new IrDA-Linux patch) 145 * o Switch from `hashbin_remove' to `hashbin_remove_this' to fix 146 * a multilink bug... (depend on new IrDA-Linux patch) 147 * o fix a self->daddr to self->raddr in irda_irnet_connect to fix 148 * another multilink bug (darn !) 149 * o Remove LINKNAME_IOCTL cruft 150 * 151 * v3b - 31.8.00 - Jean II 152 * o Dump discovery log at event channel startup 153 * 154 * v4 - 28.9.00 - Jean II 155 * o Fix interaction between poll/select and dump discovery log 156 * o Add IRNET_BLOCKED_LINK event (depend on new IrDA-Linux patch) 157 * o Add IRNET_NOANSWER_FROM event (mostly to help support) 158 * o Release flow control in disconnect_indication 159 * o Block packets while connecting (speed up connections) 160 * 161 * v5 - 11.01.01 - Jean II 162 * o Init self->max_header_size, just in case... 163 * o Set up ap->chan.hdrlen, to get zero copy on tx side working. 164 * o avoid tx->ttp->flow->ppp->tx->... loop, by checking flow state 165 * Thanks to Christian Gennerat for finding this bug ! 166 * --- 167 * o Declare the proper MTU/MRU that we can support 168 * (but PPP doesn't read the MTU value :-() 169 * o Declare hashbin HB_NOLOCK instead of HB_LOCAL to avoid 170 * disabling and enabling irq twice 171 * 172 * v6 - 31.05.01 - Jean II 173 * o Print source address in Found, Discovery, Expiry & Request events 174 * o Print requested source address in /proc/net/irnet 175 * o Change control channel input. Allow multiple commands in one line. 176 * o Add saddr command to change ap->rsaddr (and use that in IrDA) 177 * --- 178 * o Make the IrDA connection procedure totally asynchronous. 179 * Heavy rewrite of the IAS query code and the whole connection 180 * procedure. Now, irnet_connect() no longer need to be called from 181 * a process context... 182 * o Enable IrDA connect retries in ppp_irnet_send(). The good thing 183 * is that IrDA connect retries are directly driven by PPP LCP 184 * retries (we retry for each LCP packet), so that everything 185 * is transparently controlled from pppd lcp-max-configure. 186 * o Add ttp_connect flag to prevent rentry on the connect procedure 187 * o Test and fixups to eliminate side effects of retries 188 * 189 * v7 - 22.08.01 - Jean II 190 * o Cleanup : Change "saddr = 0x0" to "saddr = DEV_ADDR_ANY" 191 * o Fix bug in BLOCK_WHEN_CONNECT introduced in v6 : due to the 192 * asynchronous IAS query, self->tsap is NULL when PPP send the 193 * first packet. This was preventing "connect-delay 0" to work. 194 * Change the test in ppp_irnet_send() to self->ttp_connect. 195 * 196 * v8 - 1.11.01 - Jean II 197 * o Tighten the use of self->ttp_connect and self->ttp_open to 198 * prevent various race conditions. 199 * o Avoid leaking discovery log and skb 200 * o Replace "self" with "server" in irnet_connect_indication() to 201 * better detect cut'n'paste error ;-) 202 * 203 * v9 - 29.11.01 - Jean II 204 * o Fix event generation in disconnect indication that I broke in v8 205 * It was always generation "No-Answer" because I was testing ttp_open 206 * just after clearing it. *blush*. 207 * o Use newly created irttp_listen() to fix potential crash when LAP 208 * destroyed before irnet module removed. 209 * 210 * v10 - 4.3.2 - Jean II 211 * o When receiving a disconnect indication, don't reenable the 212 * PPP Tx queue, this will trigger a reconnect. Instead, close 213 * the channel, which will kill pppd... 214 * 215 * v11 - 20.3.02 - Jean II 216 * o Oops ! v10 fix disabled IrNET retries and passive behaviour. 217 * Better fix in irnet_disconnect_indication() : 218 * - if connected, kill pppd via hangup. 219 * - if not connected, reenable ppp Tx, which trigger IrNET retry. 220 * 221 * v12 - 10.4.02 - Jean II 222 * o Fix race condition in irnet_connect_indication(). 223 * If the socket was already trying to connect, drop old connection 224 * and use new one only if acting as primary. See comments. 225 * 226 * v13 - 30.5.02 - Jean II 227 * o Update module init code 228 * 229 * v14 - 20.2.03 - Jean II 230 * o Add discovery hint bits in the control channel. 231 * o Remove obsolete MOD_INC/DEC_USE_COUNT in favor of .owner 232 * 233 * v15 - 7.4.03 - Jean II 234 * o Replace spin_lock_irqsave() with spin_lock_bh() so that we can 235 * use ppp_unit_number(). It's probably also better overall... 236 * o Disable call to ppp_unregister_channel(), because we can't do it. 237 */ 238 239 /***************************** INCLUDES *****************************/ 240 241 #include <linux/module.h> 242 243 #include <linux/kernel.h> 244 #include <linux/skbuff.h> 245 #include <linux/tty.h> 246 #include <linux/proc_fs.h> 247 #include <linux/netdevice.h> 248 #include <linux/miscdevice.h> 249 #include <linux/poll.h> 250 #include <linux/capability.h> 251 #include <linux/ctype.h> /* isspace() */ 252 #include <linux/string.h> /* skip_spaces() */ 253 #include <asm/uaccess.h> 254 #include <linux/init.h> 255 256 #include <linux/ppp_defs.h> 257 #include <linux/ppp-ioctl.h> 258 #include <linux/ppp_channel.h> 259 260 #include <net/irda/irda.h> 261 #include <net/irda/iriap.h> 262 #include <net/irda/irias_object.h> 263 #include <net/irda/irlmp.h> 264 #include <net/irda/irttp.h> 265 #include <net/irda/discovery.h> 266 267 /***************************** OPTIONS *****************************/ 268 /* 269 * Define or undefine to compile or not some optional part of the 270 * IrNET driver... 271 * Note : the present defaults make sense, play with that at your 272 * own risk... 273 */ 274 /* IrDA side of the business... */ 275 #define DISCOVERY_NOMASK /* To enable W2k compatibility... */ 276 #define ADVERTISE_HINT /* Advertise IrLAN hint bit */ 277 #define ALLOW_SIMULT_CONNECT /* This seem to work, cross fingers... */ 278 #define DISCOVERY_EVENTS /* Query the discovery log to post events */ 279 #define INITIAL_DISCOVERY /* Dump current discovery log as events */ 280 #undef STREAM_COMPAT /* Not needed - potentially messy */ 281 #undef CONNECT_INDIC_KICK /* Might mess IrDA, not needed */ 282 #undef FAIL_SEND_DISCONNECT /* Might mess IrDA, not needed */ 283 #undef PASS_CONNECT_PACKETS /* Not needed ? Safe */ 284 #undef MISSING_PPP_API /* Stuff I wish I could do */ 285 286 /* PPP side of the business */ 287 #define BLOCK_WHEN_CONNECT /* Block packets when connecting */ 288 #define CONNECT_IN_SEND /* Retry IrDA connection procedure */ 289 #undef FLUSH_TO_PPP /* Not sure about this one, let's play safe */ 290 #undef SECURE_DEVIRNET /* Bah... */ 291 292 /****************************** DEBUG ******************************/ 293 294 /* 295 * This set of flags enable and disable all the various warning, 296 * error and debug message of this driver. 297 * Each section can be enabled and disabled independently 298 */ 299 /* In the PPP part */ 300 #define DEBUG_CTRL_TRACE 0 /* Control channel */ 301 #define DEBUG_CTRL_INFO 0 /* various info */ 302 #define DEBUG_CTRL_ERROR 1 /* problems */ 303 #define DEBUG_FS_TRACE 0 /* filesystem callbacks */ 304 #define DEBUG_FS_INFO 0 /* various info */ 305 #define DEBUG_FS_ERROR 1 /* problems */ 306 #define DEBUG_PPP_TRACE 0 /* PPP related functions */ 307 #define DEBUG_PPP_INFO 0 /* various info */ 308 #define DEBUG_PPP_ERROR 1 /* problems */ 309 #define DEBUG_MODULE_TRACE 0 /* module insertion/removal */ 310 #define DEBUG_MODULE_ERROR 1 /* problems */ 311 312 /* In the IrDA part */ 313 #define DEBUG_IRDA_SR_TRACE 0 /* IRDA subroutines */ 314 #define DEBUG_IRDA_SR_INFO 0 /* various info */ 315 #define DEBUG_IRDA_SR_ERROR 1 /* problems */ 316 #define DEBUG_IRDA_SOCK_TRACE 0 /* IRDA main socket functions */ 317 #define DEBUG_IRDA_SOCK_INFO 0 /* various info */ 318 #define DEBUG_IRDA_SOCK_ERROR 1 /* problems */ 319 #define DEBUG_IRDA_SERV_TRACE 0 /* The IrNET server */ 320 #define DEBUG_IRDA_SERV_INFO 0 /* various info */ 321 #define DEBUG_IRDA_SERV_ERROR 1 /* problems */ 322 #define DEBUG_IRDA_TCB_TRACE 0 /* IRDA IrTTP callbacks */ 323 #define DEBUG_IRDA_CB_INFO 0 /* various info */ 324 #define DEBUG_IRDA_CB_ERROR 1 /* problems */ 325 #define DEBUG_IRDA_OCB_TRACE 0 /* IRDA other callbacks */ 326 #define DEBUG_IRDA_OCB_INFO 0 /* various info */ 327 #define DEBUG_IRDA_OCB_ERROR 1 /* problems */ 328 329 #define DEBUG_ASSERT 0 /* Verify all assertions */ 330 331 /* 332 * These are the macros we are using to actually print the debug 333 * statements. Don't look at it, it's ugly... 334 * 335 * One of the trick is that, as the DEBUG_XXX are constant, the 336 * compiler will optimise away the if() in all cases. 337 */ 338 /* All error messages (will show up in the normal logs) */ 339 #define DERROR(dbg, format, args...) \ 340 {if(DEBUG_##dbg) \ 341 printk(KERN_INFO "irnet: %s(): " format, __func__ , ##args);} 342 343 /* Normal debug message (will show up in /var/log/debug) */ 344 #define DEBUG(dbg, format, args...) \ 345 {if(DEBUG_##dbg) \ 346 printk(KERN_DEBUG "irnet: %s(): " format, __func__ , ##args);} 347 348 /* Entering a function (trace) */ 349 #define DENTER(dbg, format, args...) \ 350 {if(DEBUG_##dbg) \ 351 printk(KERN_DEBUG "irnet: -> %s" format, __func__ , ##args);} 352 353 /* Entering and exiting a function in one go (trace) */ 354 #define DPASS(dbg, format, args...) \ 355 {if(DEBUG_##dbg) \ 356 printk(KERN_DEBUG "irnet: <>%s" format, __func__ , ##args);} 357 358 /* Exiting a function (trace) */ 359 #define DEXIT(dbg, format, args...) \ 360 {if(DEBUG_##dbg) \ 361 printk(KERN_DEBUG "irnet: <-%s()" format, __func__ , ##args);} 362 363 /* Exit a function with debug */ 364 #define DRETURN(ret, dbg, args...) \ 365 {DEXIT(dbg, ": " args);\ 366 return ret; } 367 368 /* Exit a function on failed condition */ 369 #define DABORT(cond, ret, dbg, args...) \ 370 {if(cond) {\ 371 DERROR(dbg, args);\ 372 return ret; }} 373 374 /* Invalid assertion, print out an error and exit... */ 375 #define DASSERT(cond, ret, dbg, args...) \ 376 {if((DEBUG_ASSERT) && !(cond)) {\ 377 DERROR(dbg, "Invalid assertion: " args);\ 378 return ret; }} 379 380 /************************ CONSTANTS & MACROS ************************/ 381 382 /* Paranoia */ 383 #define IRNET_MAGIC 0xB00754 384 385 /* Number of control events in the control channel buffer... */ 386 #define IRNET_MAX_EVENTS 8 /* Should be more than enough... */ 387 388 /****************************** TYPES ******************************/ 389 390 /* 391 * This is the main structure where we store all the data pertaining to 392 * one instance of irnet. 393 * Note : in irnet functions, a pointer this structure is usually called 394 * "ap" or "self". If the code is borrowed from the IrDA stack, it tend 395 * to be called "self", and if it is borrowed from the PPP driver it is 396 * "ap". Apart from that, it's exactly the same structure ;-) 397 */ 398 typedef struct irnet_socket 399 { 400 /* ------------------- Instance management ------------------- */ 401 /* We manage a linked list of IrNET socket instances */ 402 irda_queue_t q; /* Must be first - for hasbin */ 403 int magic; /* Paranoia */ 404 405 /* --------------------- FileSystem part --------------------- */ 406 /* "pppd" interact directly with us on a /dev/ file */ 407 struct file * file; /* File descriptor of this instance */ 408 /* TTY stuff - to keep "pppd" happy */ 409 struct ktermios termios; /* Various tty flags */ 410 /* Stuff for the control channel */ 411 int event_index; /* Last read in the event log */ 412 413 /* ------------------------- PPP part ------------------------- */ 414 /* We interface directly to the ppp_generic driver in the kernel */ 415 int ppp_open; /* registered with ppp_generic */ 416 struct ppp_channel chan; /* Interface to generic ppp layer */ 417 418 int mru; /* Max size of PPP payload */ 419 u32 xaccm[8]; /* Asynchronous character map (just */ 420 u32 raccm; /* to please pppd - dummy) */ 421 unsigned int flags; /* PPP flags (compression, ...) */ 422 unsigned int rbits; /* Unused receive flags ??? */ 423 struct work_struct disconnect_work; /* Process context disconnection */ 424 /* ------------------------ IrTTP part ------------------------ */ 425 /* We create a pseudo "socket" over the IrDA tranport */ 426 unsigned long ttp_open; /* Set when IrTTP is ready */ 427 unsigned long ttp_connect; /* Set when IrTTP is connecting */ 428 struct tsap_cb * tsap; /* IrTTP instance (the connection) */ 429 430 char rname[NICKNAME_MAX_LEN + 1]; 431 /* IrDA nickname of destination */ 432 __u32 rdaddr; /* Requested peer IrDA address */ 433 __u32 rsaddr; /* Requested local IrDA address */ 434 __u32 daddr; /* actual peer IrDA address */ 435 __u32 saddr; /* my local IrDA address */ 436 __u8 dtsap_sel; /* Remote TSAP selector */ 437 __u8 stsap_sel; /* Local TSAP selector */ 438 439 __u32 max_sdu_size_rx;/* Socket parameters used for IrTTP */ 440 __u32 max_sdu_size_tx; 441 __u32 max_data_size; 442 __u8 max_header_size; 443 LOCAL_FLOW tx_flow; /* State of the Tx path in IrTTP */ 444 445 /* ------------------- IrLMP and IrIAS part ------------------- */ 446 /* Used for IrDA Discovery and socket name resolution */ 447 void * ckey; /* IrLMP client handle */ 448 __u16 mask; /* Hint bits mask (filter discov.)*/ 449 int nslots; /* Number of slots for discovery */ 450 451 struct iriap_cb * iriap; /* Used to query remote IAS */ 452 int errno; /* status of the IAS query */ 453 454 /* -------------------- Discovery log part -------------------- */ 455 /* Used by initial discovery on the control channel 456 * and by irnet_discover_daddr_and_lsap_sel() */ 457 struct irda_device_info *discoveries; /* Copy of the discovery log */ 458 int disco_index; /* Last read in the discovery log */ 459 int disco_number; /* Size of the discovery log */ 460 461 struct mutex lock; 462 463 } irnet_socket; 464 465 /* 466 * This is the various event that we will generate on the control channel 467 */ 468 typedef enum irnet_event 469 { 470 IRNET_DISCOVER, /* New IrNET node discovered */ 471 IRNET_EXPIRE, /* IrNET node expired */ 472 IRNET_CONNECT_TO, /* IrNET socket has connected to other node */ 473 IRNET_CONNECT_FROM, /* Other node has connected to IrNET socket */ 474 IRNET_REQUEST_FROM, /* Non satisfied connection request */ 475 IRNET_NOANSWER_FROM, /* Failed connection request */ 476 IRNET_BLOCKED_LINK, /* Link (IrLAP) is blocked for > 3s */ 477 IRNET_DISCONNECT_FROM, /* IrNET socket has disconnected */ 478 IRNET_DISCONNECT_TO /* Closing IrNET socket */ 479 } irnet_event; 480 481 /* 482 * This is the storage for an event and its arguments 483 */ 484 typedef struct irnet_log 485 { 486 irnet_event event; 487 int unit; 488 __u32 saddr; 489 __u32 daddr; 490 char name[NICKNAME_MAX_LEN + 1]; /* 21 + 1 */ 491 __u16_host_order hints; /* Discovery hint bits */ 492 } irnet_log; 493 494 /* 495 * This is the storage for all events and related stuff... 496 */ 497 typedef struct irnet_ctrl_channel 498 { 499 irnet_log log[IRNET_MAX_EVENTS]; /* Event log */ 500 int index; /* Current index in log */ 501 spinlock_t spinlock; /* Serialize access to the event log */ 502 wait_queue_head_t rwait; /* processes blocked on read (or poll) */ 503 } irnet_ctrl_channel; 504 505 /**************************** PROTOTYPES ****************************/ 506 /* 507 * Global functions of the IrNET module 508 * Note : we list here also functions called from one file to the other. 509 */ 510 511 /* -------------------------- IRDA PART -------------------------- */ 512 extern int 513 irda_irnet_create(irnet_socket *); /* Initialise a IrNET socket */ 514 extern int 515 irda_irnet_connect(irnet_socket *); /* Try to connect over IrDA */ 516 extern void 517 irda_irnet_destroy(irnet_socket *); /* Teardown a IrNET socket */ 518 extern int 519 irda_irnet_init(void); /* Initialise IrDA part of IrNET */ 520 extern void 521 irda_irnet_cleanup(void); /* Teardown IrDA part of IrNET */ 522 523 /**************************** VARIABLES ****************************/ 524 525 /* Control channel stuff - allocated in irnet_irda.h */ 526 extern struct irnet_ctrl_channel irnet_events; 527 528 #endif /* IRNET_H */ 529