/***************************************************************************** * wanmain.c WAN Multiprotocol Router Module. Main code. * * This module is completely hardware-independent and provides * the following common services for the WAN Link Drivers: * o WAN device managenment (registering, unregistering) * o Network interface management * o Physical connection management (dial-up, incomming calls) * o Logical connection management (switched virtual circuits) * o Protocol encapsulation/decapsulation * * Author: Gene Kozin * * Copyright: (c) 1995-1997 Sangoma Technologies Inc. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * ============================================================================ * Dec 27, 1996 Gene Kozin Initial version (based on Sangoma's WANPIPE) * Jan 16, 1997 Gene Kozin router_devlist made public * Jan 31, 1997 Alan Cox Hacked it about a bit for 2.1 * Jun 27, 1997 Alan Cox realigned with vendor code * Oct 15, 1997 Farhan Thawar changed wan_encapsulate to add a pad byte of 0 * Apr 20, 1998 Alan Cox Fixed 2.1 symbols * May 17, 1998 K. Baranowski Fixed SNAP encapsulation in wan_encapsulate *****************************************************************************/ #include /* offsetof(), etc. */ #include /* return codes */ #include #include /* support for loadable modules */ #include /* kmalloc(), kfree() */ #include /* verify_area(), etc. */ #include /* inline mem*, str* functions */ #include /* kernel <-> user copy */ #include /* htons(), etc. */ #include /* copy_to/from_user */ #include /* WAN router API definitions */ #include /* __initfunc et al. */ /****** Defines and Macros **************************************************/ #ifndef min #define min(a,b) (((a)<(b))?(a):(b)) #endif #ifndef max #define max(a,b) (((a)>(b))?(a):(b)) #endif /****** Function Prototypes *************************************************/ /* * Kernel loadable module interface. */ #ifdef MODULE int init_module (void); void cleanup_module (void); #endif /* * WAN device IOCTL handlers */ static int device_setup (wan_device_t* wandev, wandev_conf_t* u_conf); static int device_stat (wan_device_t* wandev, wandev_stat_t* u_stat); static int device_shutdown (wan_device_t* wandev); static int device_new_if (wan_device_t* wandev, wanif_conf_t* u_conf); static int device_del_if (wan_device_t* wandev, char* u_name); /* * Miscellaneous */ static wan_device_t* find_device (char* name); static int delete_interface (wan_device_t* wandev, char* name, int forse); /* * Global Data */ #ifdef MODULE static char fullname[] = "WAN Router"; static char copyright[] = "(c) 1995-1997 Sangoma Technologies Inc."; #endif static char modname[] = ROUTER_NAME; /* short module name */ wan_device_t * router_devlist = NULL; /* list of registered devices */ static int devcnt = 0; /* * Organizationally Unique Identifiers for encapsulation/decapsulation */ static unsigned char oui_ether[] = { 0x00, 0x00, 0x00 }; #if 0 static unsigned char oui_802_2[] = { 0x00, 0x80, 0xC2 }; #endif #ifdef MODULE /* * Kernel Loadable Module Entry Points */ /* * Module 'insert' entry point. * o print announcement * o initialize static data * o create /proc/net/router directory and static entries * * Return: 0 Ok * < 0 error. * Context: process */ int init_module (void) { int err; printk(KERN_INFO "%s v%u.%u %s\n", fullname, ROUTER_VERSION, ROUTER_RELEASE, copyright); err = wanrouter_proc_init(); if (err) printk(KERN_ERR "%s: can't create entry in proc filesystem!\n", modname); return err; } /* * Module 'remove' entry point. * o delete /proc/net/router directory and static entries. */ void cleanup_module (void) { wanrouter_proc_cleanup(); } #else __initfunc(void wanrouter_init(void)) { int err = wanrouter_proc_init(); if (err) printk(KERN_ERR "%s: can't create entry in proc filesystem!\n", modname); } #endif /* * Kernel APIs */ /* * Register WAN device. * o verify device credentials * o create an entry for the device in the /proc/net/router directory * o initialize internally maintained fields of the wan_device structure * o link device data space to a singly-linked list * o if it's the first device, then start kernel 'thread' * o increment module use count * * Return: * 0 Ok * < 0 error. * * Context: process */ int register_wan_device(wan_device_t* wandev) { int err, namelen; if ((wandev == NULL) || (wandev->magic != ROUTER_MAGIC) || (wandev->name == NULL)) return -EINVAL; namelen = strlen(wandev->name); if (!namelen || (namelen > WAN_DRVNAME_SZ)) return -EINVAL; if (find_device(wandev->name) != NULL) return -EEXIST; #ifdef WANDEBUG printk(KERN_INFO "%s: registering WAN device %s\n", modname, wandev->name); #endif /* * Register /proc directory entry */ err = wanrouter_proc_add(wandev); if (err) { printk(KERN_ERR "%s: can't create /proc/net/router/%s entry!\n", modname, wandev->name) ; return err; } /* * Initialize fields of the wan_device structure maintained by the * router and update local data. */ wandev->ndev = 0; wandev->dev = NULL; wandev->next = router_devlist; router_devlist = wandev; ++devcnt; MOD_INC_USE_COUNT; /* prevent module from unloading */ return 0; } /* * Unregister WAN device. * o shut down device * o unlink device data space from the linked list * o delete device entry in the /proc/net/router directory * o decrement module use count * * Return: 0 Ok * <0 error. * Context: process */ int unregister_wan_device(char* name) { wan_device_t *wandev, *prev; if (name == NULL) return -EINVAL; for (wandev = router_devlist, prev = NULL; wandev && strcmp(wandev->name, name); prev = wandev, wandev = wandev->next) ; if (wandev == NULL) return -ENODEV; #ifdef WANDEBUG printk(KERN_INFO "%s: unregistering WAN device %s\n", modname, name); #endif if (wandev->state != WAN_UNCONFIGURED) { while(wandev->dev) delete_interface(wandev, wandev->dev->name, 1); if (wandev->shutdown) wandev->shutdown(wandev); } if (prev) prev->next = wandev->next; else router_devlist = wandev->next; --devcnt; wanrouter_proc_delete(wandev); MOD_DEC_USE_COUNT; return 0; } /* * Encapsulate packet. * * Return: encapsulation header size * < 0 - unsupported Ethertype * * Notes: * 1. This function may be called on interrupt context. */ int wanrouter_encapsulate (struct sk_buff* skb, struct device* dev) { int hdr_len = 0; switch (skb->protocol) { case ETH_P_IP: /* IP datagram encapsulation */ hdr_len += 1; skb_push(skb, 1); skb->data[0] = NLPID_IP; break; case ETH_P_IPX: /* SNAP encapsulation */ case ETH_P_ARP: hdr_len += 7; skb_push(skb, 7); skb->data[0] = 0; skb->data[1] = NLPID_SNAP; memcpy(&skb->data[2], oui_ether, sizeof(oui_ether)); *((unsigned short*)&skb->data[5]) = htons(skb->protocol); break; default: /* Unknown packet type */ printk(KERN_INFO "%s: unsupported Ethertype 0x%04X on interface %s!\n", modname, skb->protocol, dev->name); hdr_len = -EINVAL; } return hdr_len; } /* * Decapsulate packet. * * Return: Ethertype (in network order) * 0 unknown encapsulation * * Notes: * 1. This function may be called on interrupt context. */ unsigned short wanrouter_type_trans (struct sk_buff* skb, struct device* dev) { int cnt = skb->data[0] ? 0 : 1; /* there may be a pad present */ unsigned short ethertype; switch (skb->data[cnt]) { case NLPID_IP: /* IP datagramm */ ethertype = htons(ETH_P_IP); cnt += 1; break; case NLPID_SNAP: /* SNAP encapsulation */ if (memcmp(&skb->data[cnt + 1], oui_ether, sizeof(oui_ether))) { printk(KERN_INFO "%s: unsupported SNAP OUI %02X-%02X-%02X " "on interface %s!\n", modname, skb->data[cnt+1], skb->data[cnt+2], skb->data[cnt+3], dev->name); ; return 0; } ethertype = *((unsigned short*)&skb->data[cnt+4]); cnt += 6; break; /* add other protocols, e.g. CLNP, ESIS, ISIS, if needed */ default: printk(KERN_INFO "%s: unsupported NLPID 0x%02X on interface %s!\n", modname, skb->data[cnt], dev->name) ; return 0; } skb->protocol = ethertype; skb->pkt_type = PACKET_HOST; /* Physically point to point */ skb->mac.raw = skb->data; skb_pull(skb, cnt); return ethertype; } /* * WAN device IOCTL. * o find WAN device associated with this node * o execute requested action or pass command to the device driver */ int wanrouter_ioctl(struct inode* inode, struct file* file, unsigned int cmd, unsigned long arg) { int err = 0; struct proc_dir_entry* dent; wan_device_t* wandev; if (!capable(CAP_NET_ADMIN)){ return -EPERM; } if ((cmd >> 8) != ROUTER_IOCTL) return -EINVAL; dent = inode->u.generic_ip; if ((dent == NULL) || (dent->data == NULL)) return -EINVAL; wandev = dent->data; if (wandev->magic != ROUTER_MAGIC) return -EINVAL; switch (cmd) { case ROUTER_SETUP: err = device_setup(wandev, (void*)arg); break; case ROUTER_DOWN: err = device_shutdown(wandev); break; case ROUTER_STAT: err = device_stat(wandev, (void*)arg); break; case ROUTER_IFNEW: err = device_new_if(wandev, (void*)arg); break; case ROUTER_IFDEL: err = device_del_if(wandev, (void*)arg); break; case ROUTER_IFSTAT: break; default: if ((cmd >= ROUTER_USER) && (cmd <= ROUTER_USER_MAX) && wandev->ioctl) err = wandev->ioctl(wandev, cmd, arg) ; else err = -EINVAL; } return err; } /* * WAN Driver IOCTL Handlers */ /* * Setup WAN link device. * o verify user address space * o allocate kernel memory and copy configuration data to kernel space * o if configuration data includes extension, copy it to kernel space too * o call driver's setup() entry point */ static int device_setup (wan_device_t* wandev, wandev_conf_t* u_conf) { void* data; wandev_conf_t* conf; int err= -EINVAL; if (wandev->setup == NULL) /* Nothing to do ? */ return 0; conf = kmalloc(sizeof(wandev_conf_t), GFP_KERNEL); if (conf == NULL) return -ENOBUFS; if(copy_from_user(conf, u_conf, sizeof(wandev_conf_t))) { kfree(conf); return -EFAULT; } if (conf->magic != ROUTER_MAGIC) goto bail; if (conf->data_size && conf->data) { if(conf->data_size > 64000 || conf->data_size < 0){ goto bail; } data = kmalloc(conf->data_size, GFP_KERNEL); if (data) { if(!copy_from_user(data, conf->data, conf->data_size)) { conf->data=data; wandev->setup(wandev,conf); err = 0; } else err = -ENOBUFS; } if (data) kfree(data); } bail: kfree(conf); return err; } /* * Shutdown WAN device. * o delete all not opened logical channels for this device * o call driver's shutdown() entry point */ static int device_shutdown (wan_device_t* wandev) { struct device* dev; if (wandev->state == WAN_UNCONFIGURED) return 0; for (dev = wandev->dev; dev;) { if (delete_interface(wandev, dev->name, 0)) dev = dev->slave; } if (wandev->ndev) return -EBUSY; /* there are opened interfaces */ if (wandev->shutdown) return wandev->shutdown(wandev); return 0; } /* * Get WAN device status & statistics. */ static int device_stat (wan_device_t* wandev, wandev_stat_t* u_stat) { wandev_stat_t stat; memset(&stat, 0, sizeof(stat)); /* Ask device driver to update device statistics */ if ((wandev->state != WAN_UNCONFIGURED) && wandev->update) wandev->update(wandev); /* Fill out structure */ stat.ndev = wandev->ndev; stat.state = wandev->state; if(copy_to_user(u_stat, &stat, sizeof(stat))) return -EFAULT; return 0; } /* * Create new WAN interface. * o verify user address space * o copy configuration data to kernel address space * o allocate network interface data space * o call driver's new_if() entry point * o make sure there is no interface name conflict * o register network interface */ static int device_new_if (wan_device_t* wandev, wanif_conf_t* u_conf) { wanif_conf_t conf; struct device* dev; int err; if ((wandev->state == WAN_UNCONFIGURED) || (wandev->new_if == NULL)) return -ENODEV; if(copy_from_user(&conf, u_conf, sizeof(wanif_conf_t))) return -EFAULT; if (conf.magic != ROUTER_MAGIC) return -EINVAL; dev = kmalloc(sizeof(struct device), GFP_KERNEL); if (dev == NULL) return -ENOBUFS; memset(dev, 0, sizeof(struct device)); err = wandev->new_if(wandev, dev, &conf); if (!err) { /* Register network interface. This will invoke init() * function supplied by the driver. If device registered * successfully, add it to the interface list. */ if (dev->name == NULL) err = -EINVAL; else if (dev_get(dev->name)) err = -EEXIST; /* name already exists */ else { #ifdef WANDEBUG printk(KERN_INFO "%s: registering interface %s...\n", modname, dev->name); #endif err = register_netdev(dev); if (!err) { cli(); /***** critical section start *****/ dev->slave = wandev->dev; wandev->dev = dev; ++wandev->ndev; sti(); /****** critical section end ******/ return 0; /* done !!! */ } } if (wandev->del_if) wandev->del_if(wandev, dev); } kfree(dev); return err; } /* * Delete WAN logical channel. * o verify user address space * o copy configuration data to kernel address space */ static int device_del_if (wan_device_t* wandev, char* u_name) { char name[WAN_IFNAME_SZ + 1]; if (wandev->state == WAN_UNCONFIGURED) return -ENODEV; memset(name, 0, sizeof(name)); if(copy_from_user(name, u_name, WAN_IFNAME_SZ)) return -EFAULT; return delete_interface(wandev, name, 0); } /* * Miscellaneous Functions */ /* * Find WAN device by name. * Return pointer to the WAN device data space or NULL if device not found. */ static wan_device_t* find_device (char* name) { wan_device_t* wandev; for (wandev = router_devlist;wandev && strcmp(wandev->name, name); wandev = wandev->next); return wandev; } /* * Delete WAN logical channel identified by its name. * o find logical channel by its name * o call driver's del_if() entry point * o unregister network interface * o unlink channel data space from linked list of channels * o release channel data space * * Return: 0 success * -ENODEV channel not found. * -EBUSY interface is open * * Note: If (force != 0), then device will be destroyed even if interface * associated with it is open. It's caller's responsibility to make * sure that opened interfaces are not removed! */ static int delete_interface (wan_device_t* wandev, char* name, int force) { struct device *dev, *prev; for (dev = wandev->dev, prev = NULL; dev && strcmp(name, dev->name); prev = dev, dev = dev->slave); if (dev == NULL) return -ENODEV; /* interface not found */ if (dev->start) { if (force) { printk(KERN_WARNING "%s: deleting opened interface %s!\n",modname, name); } else return -EBUSY; /* interface in use */ } if (wandev->del_if) wandev->del_if(wandev, dev); cli(); /***** critical section start *****/ if (prev) prev->slave = dev->slave; else wandev->dev = dev->slave; --wandev->ndev; sti(); /****** critical section end ******/ printk("Unregistering '%s'\n", dev->name); unregister_netdev(dev); kfree(dev); return 0; } #ifdef MODULE EXPORT_SYMBOL(register_wan_device); EXPORT_SYMBOL(unregister_wan_device); EXPORT_SYMBOL(wanrouter_encapsulate); EXPORT_SYMBOL(wanrouter_type_trans); #endif /* * End */