/* * IrNET protocol module : Synchronous PPP over an IrDA socket. * * Jean II - HPL `00 - * * This file implement the PPP interface and /dev/irnet character device. * The PPP interface hook to the ppp_generic module, handle all our * relationship to the PPP code in the kernel (and by extension to pppd), * and exchange PPP frames with this module (send/receive). * The /dev/irnet device is used primarily for 2 functions : * 1) as a stub for pppd (the ppp daemon), so that we can appropriately * generate PPP sessions (we pretend we are a tty). * 2) as a control channel (write commands, read events) */ #include #include #include "irnet_ppp.h" /* Private header */ /* Please put other headers in irnet.h - Thanks */ /* Generic PPP callbacks (to call us) */ static const struct ppp_channel_ops irnet_ppp_ops = { .start_xmit = ppp_irnet_send, .ioctl = ppp_irnet_ioctl }; /************************* CONTROL CHANNEL *************************/ /* * When a pppd instance is not active on /dev/irnet, it acts as a control * channel. * Writing allow to set up the IrDA destination of the IrNET channel, * and any application may be read events happening in IrNET... */ /*------------------------------------------------------------------*/ /* * Write is used to send a command to configure a IrNET channel * before it is open by pppd. The syntax is : "command argument" * Currently there is only two defined commands : * o name : set the requested IrDA nickname of the IrNET peer. * o addr : set the requested IrDA address of the IrNET peer. * Note : the code is crude, but effective... */ static inline ssize_t irnet_ctrl_write(irnet_socket * ap, const char __user *buf, size_t count) { char command[IRNET_MAX_COMMAND]; char * start; /* Current command being processed */ char * next; /* Next command to process */ int length; /* Length of current command */ DENTER(CTRL_TRACE, "(ap=0x%p, count=%Zd)\n", ap, count); /* Check for overflow... */ DABORT(count >= IRNET_MAX_COMMAND, -ENOMEM, CTRL_ERROR, "Too much data !!!\n"); /* Get the data in the driver */ if(copy_from_user(command, buf, count)) { DERROR(CTRL_ERROR, "Invalid user space pointer.\n"); return -EFAULT; } /* Safe terminate the string */ command[count] = '\0'; DEBUG(CTRL_INFO, "Command line received is ``%s'' (%Zd).\n", command, count); /* Check every commands in the command line */ next = command; while(next != NULL) { /* Look at the next command */ start = next; /* Scrap whitespaces before the command */ start = skip_spaces(start); /* ',' is our command separator */ next = strchr(start, ','); if(next) { *next = '\0'; /* Terminate command */ length = next - start; /* Length */ next++; /* Skip the '\0' */ } else length = strlen(start); DEBUG(CTRL_INFO, "Found command ``%s'' (%d).\n", start, length); /* Check if we recognised one of the known command * We can't use "switch" with strings, so hack with "continue" */ /* First command : name -> Requested IrDA nickname */ if(!strncmp(start, "name", 4)) { /* Copy the name only if is included and not "any" */ if((length > 5) && (strcmp(start + 5, "any"))) { /* Strip out trailing whitespaces */ while(isspace(start[length - 1])) length--; DABORT(length < 5 || length > NICKNAME_MAX_LEN + 5, -EINVAL, CTRL_ERROR, "Invalid nickname.\n"); /* Copy the name for later reuse */ memcpy(ap->rname, start + 5, length - 5); ap->rname[length - 5] = '\0'; } else ap->rname[0] = '\0'; DEBUG(CTRL_INFO, "Got rname = ``%s''\n", ap->rname); /* Restart the loop */ continue; } /* Second command : addr, daddr -> Requested IrDA destination address * Also process : saddr -> Requested IrDA source address */ if((!strncmp(start, "addr", 4)) || (!strncmp(start, "daddr", 5)) || (!strncmp(start, "saddr", 5))) { __u32 addr = DEV_ADDR_ANY; /* Copy the address only if is included and not "any" */ if((length > 5) && (strcmp(start + 5, "any"))) { char * begp = start + 5; char * endp; /* Scrap whitespaces before the command */ begp = skip_spaces(begp); /* Convert argument to a number (last arg is the base) */ addr = simple_strtoul(begp, &endp, 16); /* Has it worked ? (endp should be start + length) */ DABORT(endp <= (start + 5), -EINVAL, CTRL_ERROR, "Invalid address.\n"); } /* Which type of address ? */ if(start[0] == 's') { /* Save it */ ap->rsaddr = addr; DEBUG(CTRL_INFO, "Got rsaddr = %08x\n", ap->rsaddr); } else { /* Save it */ ap->rdaddr = addr; DEBUG(CTRL_INFO, "Got rdaddr = %08x\n", ap->rdaddr); } /* Restart the loop */ continue; } /* Other possible command : connect N (number of retries) */ /* No command matched -> Failed... */ DABORT(1, -EINVAL, CTRL_ERROR, "Not a recognised IrNET command.\n"); } /* Success : we have parsed all commands successfully */ return count; } #ifdef INITIAL_DISCOVERY /*------------------------------------------------------------------*/ /* * Function irnet_get_discovery_log (self) * * Query the content on the discovery log if not done * * This function query the current content of the discovery log * at the startup of the event channel and save it in the internal struct. */ static void irnet_get_discovery_log(irnet_socket * ap) { __u16 mask = irlmp_service_to_hint(S_LAN); /* Ask IrLMP for the current discovery log */ ap->discoveries = irlmp_get_discoveries(&ap->disco_number, mask, DISCOVERY_DEFAULT_SLOTS); /* Check if the we got some results */ if(ap->discoveries == NULL) ap->disco_number = -1; DEBUG(CTRL_INFO, "Got the log (0x%p), size is %d\n", ap->discoveries, ap->disco_number); } /*------------------------------------------------------------------*/ /* * Function irnet_read_discovery_log (self, event) * * Read the content on the discovery log * * This function dump the current content of the discovery log * at the startup of the event channel. * Return 1 if wrote an event on the control channel... * * State of the ap->disco_XXX variables : * Socket creation : discoveries = NULL ; disco_index = 0 ; disco_number = 0 * While reading : discoveries = ptr ; disco_index = X ; disco_number = Y * After reading : discoveries = NULL ; disco_index = Y ; disco_number = -1 */ static inline int irnet_read_discovery_log(irnet_socket *ap, char *event, int buf_size) { int done_event = 0; DENTER(CTRL_TRACE, "(ap=0x%p, event=0x%p)\n", ap, event); /* Test if we have some work to do or we have already finished */ if(ap->disco_number == -1) { DEBUG(CTRL_INFO, "Already done\n"); return 0; } /* Test if it's the first time and therefore we need to get the log */ if(ap->discoveries == NULL) irnet_get_discovery_log(ap); /* Check if we have more item to dump */ if(ap->disco_index < ap->disco_number) { /* Write an event */ snprintf(event, buf_size, "Found %08x (%s) behind %08x {hints %02X-%02X}\n", ap->discoveries[ap->disco_index].daddr, ap->discoveries[ap->disco_index].info, ap->discoveries[ap->disco_index].saddr, ap->discoveries[ap->disco_index].hints[0], ap->discoveries[ap->disco_index].hints[1]); DEBUG(CTRL_INFO, "Writing discovery %d : %s\n", ap->disco_index, ap->discoveries[ap->disco_index].info); /* We have an event */ done_event = 1; /* Next discovery */ ap->disco_index++; } /* Check if we have done the last item */ if(ap->disco_index >= ap->disco_number) { /* No more items : remove the log and signal termination */ DEBUG(CTRL_INFO, "Cleaning up log (0x%p)\n", ap->discoveries); if(ap->discoveries != NULL) { /* Cleanup our copy of the discovery log */ kfree(ap->discoveries); ap->discoveries = NULL; } ap->disco_number = -1; } return done_event; } #endif /* INITIAL_DISCOVERY */ /*------------------------------------------------------------------*/ /* * Read is used to get IrNET events */ static inline ssize_t irnet_ctrl_read(irnet_socket * ap, struct file * file, char __user * buf, size_t count) { DECLARE_WAITQUEUE(wait, current); char event[75]; ssize_t ret = 0; DENTER(CTRL_TRACE, "(ap=0x%p, count=%Zd)\n", ap, count); #ifdef INITIAL_DISCOVERY /* Check if we have read the log */ if (irnet_read_discovery_log(ap, event, sizeof(event))) { count = min(strlen(event), count); if (copy_to_user(buf, event, count)) { DERROR(CTRL_ERROR, "Invalid user space pointer.\n"); return -EFAULT; } DEXIT(CTRL_TRACE, "\n"); return count; } #endif /* INITIAL_DISCOVERY */ /* Put ourselves on the wait queue to be woken up */ add_wait_queue(&irnet_events.rwait, &wait); set_current_state(TASK_INTERRUPTIBLE); for(;;) { /* If there is unread events */ ret = 0; if(ap->event_index != irnet_events.index) break; ret = -EAGAIN; if(file->f_flags & O_NONBLOCK) break; ret = -ERESTARTSYS; if(signal_pending(current)) break; /* Yield and wait to be woken up */ schedule(); } __set_current_state(TASK_RUNNING); remove_wait_queue(&irnet_events.rwait, &wait); /* Did we got it ? */ if(ret != 0) { /* No, return the error code */ DEXIT(CTRL_TRACE, " - ret %Zd\n", ret); return ret; } /* Which event is it ? */ switch(irnet_events.log[ap->event_index].event) { case IRNET_DISCOVER: snprintf(event, sizeof(event), "Discovered %08x (%s) behind %08x {hints %02X-%02X}\n", irnet_events.log[ap->event_index].daddr, irnet_events.log[ap->event_index].name, irnet_events.log[ap->event_index].saddr, irnet_events.log[ap->event_index].hints.byte[0], irnet_events.log[ap->event_index].hints.byte[1]); break; case IRNET_EXPIRE: snprintf(event, sizeof(event), "Expired %08x (%s) behind %08x {hints %02X-%02X}\n", irnet_events.log[ap->event_index].daddr, irnet_events.log[ap->event_index].name, irnet_events.log[ap->event_index].saddr, irnet_events.log[ap->event_index].hints.byte[0], irnet_events.log[ap->event_index].hints.byte[1]); break; case IRNET_CONNECT_TO: snprintf(event, sizeof(event), "Connected to %08x (%s) on ppp%d\n", irnet_events.log[ap->event_index].daddr, irnet_events.log[ap->event_index].name, irnet_events.log[ap->event_index].unit); break; case IRNET_CONNECT_FROM: snprintf(event, sizeof(event), "Connection from %08x (%s) on ppp%d\n", irnet_events.log[ap->event_index].daddr, irnet_events.log[ap->event_index].name, irnet_events.log[ap->event_index].unit); break; case IRNET_REQUEST_FROM: snprintf(event, sizeof(event), "Request from %08x (%s) behind %08x\n", irnet_events.log[ap->event_index].daddr, irnet_events.log[ap->event_index].name, irnet_events.log[ap->event_index].saddr); break; case IRNET_NOANSWER_FROM: snprintf(event, sizeof(event), "No-answer from %08x (%s) on ppp%d\n", irnet_events.log[ap->event_index].daddr, irnet_events.log[ap->event_index].name, irnet_events.log[ap->event_index].unit); break; case IRNET_BLOCKED_LINK: snprintf(event, sizeof(event), "Blocked link with %08x (%s) on ppp%d\n", irnet_events.log[ap->event_index].daddr, irnet_events.log[ap->event_index].name, irnet_events.log[ap->event_index].unit); break; case IRNET_DISCONNECT_FROM: snprintf(event, sizeof(event), "Disconnection from %08x (%s) on ppp%d\n", irnet_events.log[ap->event_index].daddr, irnet_events.log[ap->event_index].name, irnet_events.log[ap->event_index].unit); break; case IRNET_DISCONNECT_TO: snprintf(event, sizeof(event), "Disconnected to %08x (%s)\n", irnet_events.log[ap->event_index].daddr, irnet_events.log[ap->event_index].name); break; default: snprintf(event, sizeof(event), "Bug\n"); } /* Increment our event index */ ap->event_index = (ap->event_index + 1) % IRNET_MAX_EVENTS; DEBUG(CTRL_INFO, "Event is :%s", event); count = min(strlen(event), count); if (copy_to_user(buf, event, count)) { DERROR(CTRL_ERROR, "Invalid user space pointer.\n"); return -EFAULT; } DEXIT(CTRL_TRACE, "\n"); return count; } /*------------------------------------------------------------------*/ /* * Poll : called when someone do a select on /dev/irnet. * Just check if there are new events... */ static inline unsigned int irnet_ctrl_poll(irnet_socket * ap, struct file * file, poll_table * wait) { unsigned int mask; DENTER(CTRL_TRACE, "(ap=0x%p)\n", ap); poll_wait(file, &irnet_events.rwait, wait); mask = POLLOUT | POLLWRNORM; /* If there is unread events */ if(ap->event_index != irnet_events.index) mask |= POLLIN | POLLRDNORM; #ifdef INITIAL_DISCOVERY if(ap->disco_number != -1) { /* Test if it's the first time and therefore we need to get the log */ if(ap->discoveries == NULL) irnet_get_discovery_log(ap); /* Recheck */ if(ap->disco_number != -1) mask |= POLLIN | POLLRDNORM; } #endif /* INITIAL_DISCOVERY */ DEXIT(CTRL_TRACE, " - mask=0x%X\n", mask); return mask; } /*********************** FILESYSTEM CALLBACKS ***********************/ /* * Implement the usual open, read, write functions that will be called * by the file system when some action is performed on /dev/irnet. * Most of those actions will in fact be performed by "pppd" or * the control channel, we just act as a redirector... */ /*------------------------------------------------------------------*/ /* * Open : when somebody open /dev/irnet * We basically create a new instance of irnet and initialise it. */ static int dev_irnet_open(struct inode * inode, struct file * file) { struct irnet_socket * ap; int err; DENTER(FS_TRACE, "(file=0x%p)\n", file); #ifdef SECURE_DEVIRNET /* This could (should?) be enforced by the permissions on /dev/irnet. */ if(!capable(CAP_NET_ADMIN)) return -EPERM; #endif /* SECURE_DEVIRNET */ /* Allocate a private structure for this IrNET instance */ ap = kzalloc(sizeof(*ap), GFP_KERNEL); DABORT(ap == NULL, -ENOMEM, FS_ERROR, "Can't allocate struct irnet...\n"); /* initialize the irnet structure */ ap->file = file; /* PPP channel setup */ ap->ppp_open = 0; ap->chan.private = ap; ap->chan.ops = &irnet_ppp_ops; ap->chan.mtu = (2048 - TTP_MAX_HEADER - 2 - PPP_HDRLEN); ap->chan.hdrlen = 2 + TTP_MAX_HEADER; /* for A/C + Max IrDA hdr */ /* PPP parameters */ ap->mru = (2048 - TTP_MAX_HEADER - 2 - PPP_HDRLEN); ap->xaccm[0] = ~0U; ap->xaccm[3] = 0x60000000U; ap->raccm = ~0U; /* Setup the IrDA part... */ err = irda_irnet_create(ap); if(err) { DERROR(FS_ERROR, "Can't setup IrDA link...\n"); kfree(ap); return err; } /* For the control channel */ ap->event_index = irnet_events.index; /* Cancel all past events */ mutex_init(&ap->lock); /* Put our stuff where we will be able to find it later */ file->private_data = ap; DEXIT(FS_TRACE, " - ap=0x%p\n", ap); return 0; } /*------------------------------------------------------------------*/ /* * Close : when somebody close /dev/irnet * Destroy the instance of /dev/irnet */ static int dev_irnet_close(struct inode * inode, struct file * file) { irnet_socket * ap = file->private_data; DENTER(FS_TRACE, "(file=0x%p, ap=0x%p)\n", file, ap); DABORT(ap == NULL, 0, FS_ERROR, "ap is NULL !!!\n"); /* Detach ourselves */ file->private_data = NULL; /* Close IrDA stuff */ irda_irnet_destroy(ap); /* Disconnect from the generic PPP layer if not already done */ if(ap->ppp_open) { DERROR(FS_ERROR, "Channel still registered - deregistering !\n"); ap->ppp_open = 0; ppp_unregister_channel(&ap->chan); } kfree(ap); DEXIT(FS_TRACE, "\n"); return 0; } /*------------------------------------------------------------------*/ /* * Write does nothing. * (we receive packet from ppp_generic through ppp_irnet_send()) */ static ssize_t dev_irnet_write(struct file * file, const char __user *buf, size_t count, loff_t * ppos) { irnet_socket * ap = file->private_data; DPASS(FS_TRACE, "(file=0x%p, ap=0x%p, count=%Zd)\n", file, ap, count); DABORT(ap == NULL, -ENXIO, FS_ERROR, "ap is NULL !!!\n"); /* If we are connected to ppp_generic, let it handle the job */ if(ap->ppp_open) return -EAGAIN; else return irnet_ctrl_write(ap, buf, count); } /*------------------------------------------------------------------*/ /* * Read doesn't do much either. * (pppd poll us, but ultimately reads through /dev/ppp) */ static ssize_t dev_irnet_read(struct file * file, char __user * buf, size_t count, loff_t * ppos) { irnet_socket * ap = file->private_data; DPASS(FS_TRACE, "(file=0x%p, ap=0x%p, count=%Zd)\n", file, ap, count); DABORT(ap == NULL, -ENXIO, FS_ERROR, "ap is NULL !!!\n"); /* If we are connected to ppp_generic, let it handle the job */ if(ap->ppp_open) return -EAGAIN; else return irnet_ctrl_read(ap, file, buf, count); } /*------------------------------------------------------------------*/ /* * Poll : called when someone do a select on /dev/irnet */ static unsigned int dev_irnet_poll(struct file * file, poll_table * wait) { irnet_socket * ap = file->private_data; unsigned int mask; DENTER(FS_TRACE, "(file=0x%p, ap=0x%p)\n", file, ap); mask = POLLOUT | POLLWRNORM; DABORT(ap == NULL, mask, FS_ERROR, "ap is NULL !!!\n"); /* If we are connected to ppp_generic, let it handle the job */ if(!ap->ppp_open) mask |= irnet_ctrl_poll(ap, file, wait); DEXIT(FS_TRACE, " - mask=0x%X\n", mask); return mask; } /*------------------------------------------------------------------*/ /* * IOCtl : Called when someone does some ioctls on /dev/irnet * This is the way pppd configure us and control us while the PPP * instance is active. */ static long dev_irnet_ioctl( struct file * file, unsigned int cmd, unsigned long arg) { irnet_socket * ap = file->private_data; int err; int val; void __user *argp = (void __user *)arg; DENTER(FS_TRACE, "(file=0x%p, ap=0x%p, cmd=0x%X)\n", file, ap, cmd); /* Basic checks... */ DASSERT(ap != NULL, -ENXIO, PPP_ERROR, "ap is NULL...\n"); #ifdef SECURE_DEVIRNET if(!capable(CAP_NET_ADMIN)) return -EPERM; #endif /* SECURE_DEVIRNET */ err = -EFAULT; switch(cmd) { /* Set discipline (should be N_SYNC_PPP or N_TTY) */ case TIOCSETD: if(get_user(val, (int __user *)argp)) break; if((val == N_SYNC_PPP) || (val == N_PPP)) { DEBUG(FS_INFO, "Entering PPP discipline.\n"); /* PPP channel setup (ap->chan in configured in dev_irnet_open())*/ if (mutex_lock_interruptible(&ap->lock)) return -EINTR; err = ppp_register_channel(&ap->chan); if(err == 0) { /* Our ppp side is active */ ap->ppp_open = 1; DEBUG(FS_INFO, "Trying to establish a connection.\n"); /* Setup the IrDA link now - may fail... */ irda_irnet_connect(ap); } else DERROR(FS_ERROR, "Can't setup PPP channel...\n"); mutex_unlock(&ap->lock); } else { /* In theory, should be N_TTY */ DEBUG(FS_INFO, "Exiting PPP discipline.\n"); /* Disconnect from the generic PPP layer */ if (mutex_lock_interruptible(&ap->lock)) return -EINTR; if(ap->ppp_open) { ap->ppp_open = 0; ppp_unregister_channel(&ap->chan); } else DERROR(FS_ERROR, "Channel not registered !\n"); err = 0; mutex_unlock(&ap->lock); } break; /* Query PPP channel and unit number */ case PPPIOCGCHAN: if (mutex_lock_interruptible(&ap->lock)) return -EINTR; if(ap->ppp_open && !put_user(ppp_channel_index(&ap->chan), (int __user *)argp)) err = 0; mutex_unlock(&ap->lock); break; case PPPIOCGUNIT: if (mutex_lock_interruptible(&ap->lock)) return -EINTR; if(ap->ppp_open && !put_user(ppp_unit_number(&ap->chan), (int __user *)argp)) err = 0; mutex_unlock(&ap->lock); break; /* All these ioctls can be passed both directly and from ppp_generic, * so we just deal with them in one place... */ case PPPIOCGFLAGS: case PPPIOCSFLAGS: case PPPIOCGASYNCMAP: case PPPIOCSASYNCMAP: case PPPIOCGRASYNCMAP: case PPPIOCSRASYNCMAP: case PPPIOCGXASYNCMAP: case PPPIOCSXASYNCMAP: case PPPIOCGMRU: case PPPIOCSMRU: DEBUG(FS_INFO, "Standard PPP ioctl.\n"); if(!capable(CAP_NET_ADMIN)) err = -EPERM; else { if (mutex_lock_interruptible(&ap->lock)) return -EINTR; err = ppp_irnet_ioctl(&ap->chan, cmd, arg); mutex_unlock(&ap->lock); } break; /* TTY IOCTLs : Pretend that we are a tty, to keep pppd happy */ /* Get termios */ case TCGETS: DEBUG(FS_INFO, "Get termios.\n"); if (mutex_lock_interruptible(&ap->lock)) return -EINTR; #ifndef TCGETS2 if(!kernel_termios_to_user_termios((struct termios __user *)argp, &ap->termios)) err = 0; #else if(kernel_termios_to_user_termios_1((struct termios __user *)argp, &ap->termios)) err = 0; #endif mutex_unlock(&ap->lock); break; /* Set termios */ case TCSETSF: DEBUG(FS_INFO, "Set termios.\n"); if (mutex_lock_interruptible(&ap->lock)) return -EINTR; #ifndef TCGETS2 if(!user_termios_to_kernel_termios(&ap->termios, (struct termios __user *)argp)) err = 0; #else if(!user_termios_to_kernel_termios_1(&ap->termios, (struct termios __user *)argp)) err = 0; #endif mutex_unlock(&ap->lock); break; /* Set DTR/RTS */ case TIOCMBIS: case TIOCMBIC: /* Set exclusive/non-exclusive mode */ case TIOCEXCL: case TIOCNXCL: DEBUG(FS_INFO, "TTY compatibility.\n"); err = 0; break; case TCGETA: DEBUG(FS_INFO, "TCGETA\n"); break; case TCFLSH: DEBUG(FS_INFO, "TCFLSH\n"); /* Note : this will flush buffers in PPP, so it *must* be done * We should also worry that we don't accept junk here and that * we get rid of our own buffers */ #ifdef FLUSH_TO_PPP if (mutex_lock_interruptible(&ap->lock)) return -EINTR; ppp_output_wakeup(&ap->chan); mutex_unlock(&ap->lock); #endif /* FLUSH_TO_PPP */ err = 0; break; case FIONREAD: DEBUG(FS_INFO, "FIONREAD\n"); val = 0; if(put_user(val, (int __user *)argp)) break; err = 0; break; default: DERROR(FS_ERROR, "Unsupported ioctl (0x%X)\n", cmd); err = -ENOTTY; } DEXIT(FS_TRACE, " - err = 0x%X\n", err); return err; } /************************** PPP CALLBACKS **************************/ /* * This are the functions that the generic PPP driver in the kernel * will call to communicate to us. */ /*------------------------------------------------------------------*/ /* * Prepare the ppp frame for transmission over the IrDA socket. * We make sure that the header space is enough, and we change ppp header * according to flags passed by pppd. * This is not a callback, but just a helper function used in ppp_irnet_send() */ static inline struct sk_buff * irnet_prepare_skb(irnet_socket * ap, struct sk_buff * skb) { unsigned char * data; int proto; /* PPP protocol */ int islcp; /* Protocol == LCP */ int needaddr; /* Need PPP address */ DENTER(PPP_TRACE, "(ap=0x%p, skb=0x%p)\n", ap, skb); /* Extract PPP protocol from the frame */ data = skb->data; proto = (data[0] << 8) + data[1]; /* LCP packets with codes between 1 (configure-request) * and 7 (code-reject) must be sent as though no options * have been negotiated. */ islcp = (proto == PPP_LCP) && (1 <= data[2]) && (data[2] <= 7); /* compress protocol field if option enabled */ if((data[0] == 0) && (ap->flags & SC_COMP_PROT) && (!islcp)) skb_pull(skb,1); /* Check if we need address/control fields */ needaddr = 2*((ap->flags & SC_COMP_AC) == 0 || islcp); /* Is the skb headroom large enough to contain all IrDA-headers? */ if((skb_headroom(skb) < (ap->max_header_size + needaddr)) || (skb_shared(skb))) { struct sk_buff * new_skb; DEBUG(PPP_INFO, "Reallocating skb\n"); /* Create a new skb */ new_skb = skb_realloc_headroom(skb, ap->max_header_size + needaddr); /* We have to free the original skb anyway */ dev_kfree_skb(skb); /* Did the realloc succeed ? */ DABORT(new_skb == NULL, NULL, PPP_ERROR, "Could not realloc skb\n"); /* Use the new skb instead */ skb = new_skb; } /* prepend address/control fields if necessary */ if(needaddr) { skb_push(skb, 2); skb->data[0] = PPP_ALLSTATIONS; skb->data[1] = PPP_UI; } DEXIT(PPP_TRACE, "\n"); return skb; } /*------------------------------------------------------------------*/ /* * Send a packet to the peer over the IrTTP connection. * Returns 1 iff the packet was accepted. * Returns 0 iff packet was not consumed. * If the packet was not accepted, we will call ppp_output_wakeup * at some later time to reactivate flow control in ppp_generic. */ static int ppp_irnet_send(struct ppp_channel * chan, struct sk_buff * skb) { irnet_socket * self = (struct irnet_socket *) chan->private; int ret; DENTER(PPP_TRACE, "(channel=0x%p, ap/self=0x%p)\n", chan, self); /* Check if things are somewhat valid... */ DASSERT(self != NULL, 0, PPP_ERROR, "Self is NULL !!!\n"); /* Check if we are connected */ if(!(test_bit(0, &self->ttp_open))) { #ifdef CONNECT_IN_SEND /* Let's try to connect one more time... */ /* Note : we won't be connected after this call, but we should be * ready for next packet... */ /* If we are already connecting, this will fail */ irda_irnet_connect(self); #endif /* CONNECT_IN_SEND */ DEBUG(PPP_INFO, "IrTTP not ready ! (%ld-%ld)\n", self->ttp_open, self->ttp_connect); /* Note : we can either drop the packet or block the packet. * * Blocking the packet allow us a better connection time, * because by calling ppp_output_wakeup() we can have * ppp_generic resending the LCP request immediately to us, * rather than waiting for one of pppd periodic transmission of * LCP request. * * On the other hand, if we block all packet, all those periodic * transmissions of pppd accumulate in ppp_generic, creating a * backlog of LCP request. When we eventually connect later on, * we have to transmit all this backlog before we can connect * proper (if we don't timeout before). * * The current strategy is as follow : * While we are attempting to connect, we block packets to get * a better connection time. * If we fail to connect, we drain the queue and start dropping packets */ #ifdef BLOCK_WHEN_CONNECT /* If we are attempting to connect */ if(test_bit(0, &self->ttp_connect)) { /* Blocking packet, ppp_generic will retry later */ return 0; } #endif /* BLOCK_WHEN_CONNECT */ /* Dropping packet, pppd will retry later */ dev_kfree_skb(skb); return 1; } /* Check if the queue can accept any packet, otherwise block */ if(self->tx_flow != FLOW_START) DRETURN(0, PPP_INFO, "IrTTP queue full (%d skbs)...\n", skb_queue_len(&self->tsap->tx_queue)); /* Prepare ppp frame for transmission */ skb = irnet_prepare_skb(self, skb); DABORT(skb == NULL, 1, PPP_ERROR, "Prepare skb for Tx failed.\n"); /* Send the packet to IrTTP */ ret = irttp_data_request(self->tsap, skb); if(ret < 0) { /* * > IrTTPs tx queue is full, so we just have to * > drop the frame! You might think that we should * > just return -1 and don't deallocate the frame, * > but that is dangerous since it's possible that * > we have replaced the original skb with a new * > one with larger headroom, and that would really * > confuse do_dev_queue_xmit() in dev.c! I have * > tried :-) DB * Correction : we verify the flow control above (self->tx_flow), * so we come here only if IrTTP doesn't like the packet (empty, * too large, IrTTP not connected). In those rare cases, it's ok * to drop it, we don't want to see it here again... * Jean II */ DERROR(PPP_ERROR, "IrTTP doesn't like this packet !!! (0x%X)\n", ret); /* irttp_data_request already free the packet */ } DEXIT(PPP_TRACE, "\n"); return 1; /* Packet has been consumed */ } /*------------------------------------------------------------------*/ /* * Take care of the ioctls that ppp_generic doesn't want to deal with... * Note : we are also called from dev_irnet_ioctl(). */ static int ppp_irnet_ioctl(struct ppp_channel * chan, unsigned int cmd, unsigned long arg) { irnet_socket * ap = (struct irnet_socket *) chan->private; int err; int val; u32 accm[8]; void __user *argp = (void __user *)arg; DENTER(PPP_TRACE, "(channel=0x%p, ap=0x%p, cmd=0x%X)\n", chan, ap, cmd); /* Basic checks... */ DASSERT(ap != NULL, -ENXIO, PPP_ERROR, "ap is NULL...\n"); err = -EFAULT; switch(cmd) { /* PPP flags */ case PPPIOCGFLAGS: val = ap->flags | ap->rbits; if(put_user(val, (int __user *) argp)) break; err = 0; break; case PPPIOCSFLAGS: if(get_user(val, (int __user *) argp)) break; ap->flags = val & ~SC_RCV_BITS; ap->rbits = val & SC_RCV_BITS; err = 0; break; /* Async map stuff - all dummy to please pppd */ case PPPIOCGASYNCMAP: if(put_user(ap->xaccm[0], (u32 __user *) argp)) break; err = 0; break; case PPPIOCSASYNCMAP: if(get_user(ap->xaccm[0], (u32 __user *) argp)) break; err = 0; break; case PPPIOCGRASYNCMAP: if(put_user(ap->raccm, (u32 __user *) argp)) break; err = 0; break; case PPPIOCSRASYNCMAP: if(get_user(ap->raccm, (u32 __user *) argp)) break; err = 0; break; case PPPIOCGXASYNCMAP: if(copy_to_user(argp, ap->xaccm, sizeof(ap->xaccm))) break; err = 0; break; case PPPIOCSXASYNCMAP: if(copy_from_user(accm, argp, sizeof(accm))) break; accm[2] &= ~0x40000000U; /* can't escape 0x5e */ accm[3] |= 0x60000000U; /* must escape 0x7d, 0x7e */ memcpy(ap->xaccm, accm, sizeof(ap->xaccm)); err = 0; break; /* Max PPP frame size */ case PPPIOCGMRU: if(put_user(ap->mru, (int __user *) argp)) break; err = 0; break; case PPPIOCSMRU: if(get_user(val, (int __user *) argp)) break; if(val < PPP_MRU) val = PPP_MRU; ap->mru = val; err = 0; break; default: DEBUG(PPP_INFO, "Unsupported ioctl (0x%X)\n", cmd); err = -ENOIOCTLCMD; } DEXIT(PPP_TRACE, " - err = 0x%X\n", err); return err; } /************************** INITIALISATION **************************/ /* * Module initialisation and all that jazz... */ /*------------------------------------------------------------------*/ /* * Hook our device callbacks in the filesystem, to connect our code * to /dev/irnet */ static inline int __init ppp_irnet_init(void) { int err = 0; DENTER(MODULE_TRACE, "()\n"); /* Allocate ourselves as a minor in the misc range */ err = misc_register(&irnet_misc_device); DEXIT(MODULE_TRACE, "\n"); return err; } /*------------------------------------------------------------------*/ /* * Cleanup at exit... */ static inline void __exit ppp_irnet_cleanup(void) { DENTER(MODULE_TRACE, "()\n"); /* De-allocate /dev/irnet minor in misc range */ misc_deregister(&irnet_misc_device); DEXIT(MODULE_TRACE, "\n"); } /*------------------------------------------------------------------*/ /* * Module main entry point */ static int __init irnet_init(void) { int err; /* Initialise both parts... */ err = irda_irnet_init(); if(!err) err = ppp_irnet_init(); return err; } /*------------------------------------------------------------------*/ /* * Module exit */ static void __exit irnet_cleanup(void) { irda_irnet_cleanup(); ppp_irnet_cleanup(); } /*------------------------------------------------------------------*/ /* * Module magic */ module_init(irnet_init); module_exit(irnet_cleanup); MODULE_AUTHOR("Jean Tourrilhes "); MODULE_DESCRIPTION("IrNET : Synchronous PPP over IrDA"); MODULE_LICENSE("GPL"); MODULE_ALIAS_CHARDEV(10, 187);