/* * This file implement the Wireless Extensions spy API. * * Authors : Jean Tourrilhes - HPL - <jt@hpl.hp.com> * Copyright (c) 1997-2007 Jean Tourrilhes, All Rights Reserved. * * (As all part of the Linux kernel, this file is GPL) */ #include <linux/wireless.h> #include <linux/netdevice.h> #include <linux/etherdevice.h> #include <net/iw_handler.h> #include <net/arp.h> #include <net/wext.h> static inline struct iw_spy_data *get_spydata(struct net_device *dev) { /* This is the new way */ if (dev->wireless_data) return dev->wireless_data->spy_data; return NULL; } int iw_handler_set_spy(struct net_device * dev, struct iw_request_info * info, union iwreq_data * wrqu, char * extra) { struct iw_spy_data * spydata = get_spydata(dev); struct sockaddr * address = (struct sockaddr *) extra; /* Make sure driver is not buggy or using the old API */ if (!spydata) return -EOPNOTSUPP; /* Disable spy collection while we copy the addresses. * While we copy addresses, any call to wireless_spy_update() * will NOP. This is OK, as anyway the addresses are changing. */ spydata->spy_number = 0; /* We want to operate without locking, because wireless_spy_update() * most likely will happen in the interrupt handler, and therefore * have its own locking constraints and needs performance. * The rtnl_lock() make sure we don't race with the other iw_handlers. * This make sure wireless_spy_update() "see" that the spy list * is temporarily disabled. */ smp_wmb(); /* Are there are addresses to copy? */ if (wrqu->data.length > 0) { int i; /* Copy addresses */ for (i = 0; i < wrqu->data.length; i++) memcpy(spydata->spy_address[i], address[i].sa_data, ETH_ALEN); /* Reset stats */ memset(spydata->spy_stat, 0, sizeof(struct iw_quality) * IW_MAX_SPY); } /* Make sure above is updated before re-enabling */ smp_wmb(); /* Enable addresses */ spydata->spy_number = wrqu->data.length; return 0; } EXPORT_SYMBOL(iw_handler_set_spy); int iw_handler_get_spy(struct net_device * dev, struct iw_request_info * info, union iwreq_data * wrqu, char * extra) { struct iw_spy_data * spydata = get_spydata(dev); struct sockaddr * address = (struct sockaddr *) extra; int i; /* Make sure driver is not buggy or using the old API */ if (!spydata) return -EOPNOTSUPP; wrqu->data.length = spydata->spy_number; /* Copy addresses. */ for (i = 0; i < spydata->spy_number; i++) { memcpy(address[i].sa_data, spydata->spy_address[i], ETH_ALEN); address[i].sa_family = AF_UNIX; } /* Copy stats to the user buffer (just after). */ if (spydata->spy_number > 0) memcpy(extra + (sizeof(struct sockaddr) *spydata->spy_number), spydata->spy_stat, sizeof(struct iw_quality) * spydata->spy_number); /* Reset updated flags. */ for (i = 0; i < spydata->spy_number; i++) spydata->spy_stat[i].updated &= ~IW_QUAL_ALL_UPDATED; return 0; } EXPORT_SYMBOL(iw_handler_get_spy); /*------------------------------------------------------------------*/ /* * Standard Wireless Handler : set spy threshold */ int iw_handler_set_thrspy(struct net_device * dev, struct iw_request_info *info, union iwreq_data * wrqu, char * extra) { struct iw_spy_data * spydata = get_spydata(dev); struct iw_thrspy * threshold = (struct iw_thrspy *) extra; /* Make sure driver is not buggy or using the old API */ if (!spydata) return -EOPNOTSUPP; /* Just do it */ memcpy(&(spydata->spy_thr_low), &(threshold->low), 2 * sizeof(struct iw_quality)); /* Clear flag */ memset(spydata->spy_thr_under, '\0', sizeof(spydata->spy_thr_under)); return 0; } EXPORT_SYMBOL(iw_handler_set_thrspy); /*------------------------------------------------------------------*/ /* * Standard Wireless Handler : get spy threshold */ int iw_handler_get_thrspy(struct net_device * dev, struct iw_request_info *info, union iwreq_data * wrqu, char * extra) { struct iw_spy_data * spydata = get_spydata(dev); struct iw_thrspy * threshold = (struct iw_thrspy *) extra; /* Make sure driver is not buggy or using the old API */ if (!spydata) return -EOPNOTSUPP; /* Just do it */ memcpy(&(threshold->low), &(spydata->spy_thr_low), 2 * sizeof(struct iw_quality)); return 0; } EXPORT_SYMBOL(iw_handler_get_thrspy); /*------------------------------------------------------------------*/ /* * Prepare and send a Spy Threshold event */ static void iw_send_thrspy_event(struct net_device * dev, struct iw_spy_data * spydata, unsigned char * address, struct iw_quality * wstats) { union iwreq_data wrqu; struct iw_thrspy threshold; /* Init */ wrqu.data.length = 1; wrqu.data.flags = 0; /* Copy address */ memcpy(threshold.addr.sa_data, address, ETH_ALEN); threshold.addr.sa_family = ARPHRD_ETHER; /* Copy stats */ memcpy(&(threshold.qual), wstats, sizeof(struct iw_quality)); /* Copy also thresholds */ memcpy(&(threshold.low), &(spydata->spy_thr_low), 2 * sizeof(struct iw_quality)); /* Send event to user space */ wireless_send_event(dev, SIOCGIWTHRSPY, &wrqu, (char *) &threshold); } /* ---------------------------------------------------------------- */ /* * Call for the driver to update the spy data. * For now, the spy data is a simple array. As the size of the array is * small, this is good enough. If we wanted to support larger number of * spy addresses, we should use something more efficient... */ void wireless_spy_update(struct net_device * dev, unsigned char * address, struct iw_quality * wstats) { struct iw_spy_data * spydata = get_spydata(dev); int i; int match = -1; /* Make sure driver is not buggy or using the old API */ if (!spydata) return; /* Update all records that match */ for (i = 0; i < spydata->spy_number; i++) if (!compare_ether_addr(address, spydata->spy_address[i])) { memcpy(&(spydata->spy_stat[i]), wstats, sizeof(struct iw_quality)); match = i; } /* Generate an event if we cross the spy threshold. * To avoid event storms, we have a simple hysteresis : we generate * event only when we go under the low threshold or above the * high threshold. */ if (match >= 0) { if (spydata->spy_thr_under[match]) { if (wstats->level > spydata->spy_thr_high.level) { spydata->spy_thr_under[match] = 0; iw_send_thrspy_event(dev, spydata, address, wstats); } } else { if (wstats->level < spydata->spy_thr_low.level) { spydata->spy_thr_under[match] = 1; iw_send_thrspy_event(dev, spydata, address, wstats); } } } } EXPORT_SYMBOL(wireless_spy_update);