+++ /dev/null
-/*
- * wprobe-core.c: Wireless probe interface core
- * Copyright (C) 2008-2009 Felix Fietkau <nbd@openwrt.org>
- *
- * 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.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- */
-
-#include <linux/kernel.h>
-#include <linux/version.h>
-#include <linux/module.h>
-#include <linux/types.h>
-#include <linux/spinlock.h>
-#include <linux/rcupdate.h>
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,26)
-#include <linux/rculist.h>
-#else
-#include <linux/list.h>
-#endif
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(3,2,0)
-#include <linux/prefetch.h>
-#endif
-#include <linux/skbuff.h>
-#include <linux/wprobe.h>
-#include <linux/math64.h>
-
-#define static
-
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,28)
-#define list_for_each_rcu(pos, head) \
-for (pos = rcu_dereference((head)->next); \
-prefetch(pos->next), pos != (head); \
-pos = rcu_dereference(pos->next))
-#endif
-
-#define WPROBE_MIN_INTERVAL 100 /* minimum measurement interval in msecs */
-#define WPROBE_MAX_FILTER_SIZE 1024
-#define WPROBE_MAX_FRAME_SIZE 1900
-
-static struct list_head wprobe_if;
-static spinlock_t wprobe_lock;
-
-static struct genl_family wprobe_fam = {
- .id = GENL_ID_GENERATE,
- .name = "wprobe",
- .hdrsize = 0,
- .version = 1,
- /* only the first set of attributes is used for queries */
- .maxattr = WPROBE_ATTR_LAST,
-};
-
-/* fake radiotap header */
-struct wprobe_rtap_hdr {
- __u8 version;
- __u8 padding;
- __le16 len;
- __le32 present;
-};
-
-static void wprobe_update_stats(struct wprobe_iface *dev, struct wprobe_link *l);
-static int wprobe_sync_data(struct wprobe_iface *dev, struct wprobe_link *l, bool query);
-static void wprobe_free_filter(struct wprobe_filter *f);
-
-int
-wprobe_add_link(struct wprobe_iface *s, struct wprobe_link *l, const char *addr)
-{
- unsigned long flags;
-
- INIT_LIST_HEAD(&l->list);
- l->val = kzalloc(sizeof(struct wprobe_value) * s->n_link_items, GFP_ATOMIC);
- if (!l->val)
- return -ENOMEM;
-
- l->iface = s;
- memcpy(&l->addr, addr, ETH_ALEN);
- spin_lock_irqsave(&wprobe_lock, flags);
- list_add_tail_rcu(&l->list, &s->links);
- spin_unlock_irqrestore(&wprobe_lock, flags);
-
- return 0;
-}
-EXPORT_SYMBOL(wprobe_add_link);
-
-void
-wprobe_remove_link(struct wprobe_iface *s, struct wprobe_link *l)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&wprobe_lock, flags);
- list_del_rcu(&l->list);
- spin_unlock_irqrestore(&wprobe_lock, flags);
- synchronize_rcu();
- kfree(l->val);
-}
-EXPORT_SYMBOL(wprobe_remove_link);
-
-static void
-wprobe_measure_timer(unsigned long data)
-{
- struct wprobe_iface *dev = (struct wprobe_iface *) data;
-
- /* set next measurement interval */
- mod_timer(&dev->measure_timer, jiffies +
- msecs_to_jiffies(dev->measure_interval));
-
- /* perform measurement */
- wprobe_sync_data(dev, NULL, false);
-}
-
-int
-wprobe_add_iface(struct wprobe_iface *s)
-{
- unsigned long flags;
- int vsize;
-
- /* reset only wprobe private area */
- memset(&s->list, 0, sizeof(struct wprobe_iface) - offsetof(struct wprobe_iface, list));
-
- BUG_ON(!s->name);
- INIT_LIST_HEAD(&s->list);
- INIT_LIST_HEAD(&s->links);
- setup_timer(&s->measure_timer, wprobe_measure_timer, (unsigned long) s);
-
- s->val = kzalloc(sizeof(struct wprobe_value) * s->n_global_items, GFP_ATOMIC);
- if (!s->val)
- goto error;
-
- vsize = max(s->n_link_items, s->n_global_items);
- s->query_val = kzalloc(sizeof(struct wprobe_value) * vsize, GFP_ATOMIC);
- if (!s->query_val)
- goto error;
-
- /* initialize defaults to be able to handle overflow,
- * user space will need to handle this if it keeps an
- * internal histogram */
- s->scale_min = 20;
- s->scale_max = (1 << 31);
-
- s->scale_m = 1;
- s->scale_d = 10;
-
- spin_lock_irqsave(&wprobe_lock, flags);
- list_add_rcu(&s->list, &wprobe_if);
- spin_unlock_irqrestore(&wprobe_lock, flags);
-
- return 0;
-
-error:
- if (s->val)
- kfree(s->val);
- return -ENOMEM;
-}
-EXPORT_SYMBOL(wprobe_add_iface);
-
-void
-wprobe_remove_iface(struct wprobe_iface *s)
-{
- unsigned long flags;
-
- BUG_ON(!list_empty(&s->links));
-
- del_timer_sync(&s->measure_timer);
- spin_lock_irqsave(&wprobe_lock, flags);
- list_del_rcu(&s->list);
- spin_unlock_irqrestore(&wprobe_lock, flags);
-
- /* wait for all queries to finish before freeing the
- * temporary value storage buffer */
- synchronize_rcu();
-
- kfree(s->val);
- kfree(s->query_val);
- if (s->active_filter)
- wprobe_free_filter(s->active_filter);
-}
-EXPORT_SYMBOL(wprobe_remove_iface);
-
-static struct wprobe_iface *
-wprobe_get_dev(struct nlattr *attr)
-{
- struct wprobe_iface *dev = NULL;
- struct wprobe_iface *p;
- const char *name;
- int i = 0;
-
- if (!attr)
- return NULL;
-
- name = nla_data(attr);
- list_for_each_entry_rcu(p, &wprobe_if, list) {
- i++;
- if (strcmp(name, p->name) != 0)
- continue;
-
- dev = p;
- break;
- }
-
- return dev;
-}
-
-int
-wprobe_add_frame(struct wprobe_iface *dev, const struct wprobe_wlan_hdr *hdr, void *data, int len)
-{
- struct wprobe_wlan_hdr *new_hdr;
- struct wprobe_filter *f;
- struct sk_buff *skb;
- unsigned long flags;
- int i, j;
-
- rcu_read_lock();
- f = rcu_dereference(dev->active_filter);
- if (!f)
- goto out;
-
- spin_lock_irqsave(&f->lock, flags);
-
- skb = f->skb;
- skb->len = sizeof(struct wprobe_rtap_hdr);
- skb->tail = skb->data + skb->len;
- if (len + skb->len > WPROBE_MAX_FRAME_SIZE)
- len = WPROBE_MAX_FRAME_SIZE - skb->len;
-
- new_hdr = (struct wprobe_wlan_hdr *) skb_put(skb, f->hdrlen);
- memcpy(new_hdr, hdr, sizeof(struct wprobe_wlan_hdr));
- new_hdr->len = cpu_to_be16(new_hdr->len);
-
- memcpy(skb_put(skb, len), data, len);
-
- for(i = 0; i < f->n_groups; i++) {
- struct wprobe_filter_group *fg = &f->groups[i];
- bool found = false;
- int def = -1;
-
- for (j = 0; j < fg->n_items; j++) {
- struct wprobe_filter_item *fi = fg->items[j];
-
- if (!fi->hdr.n_items) {
- def = j;
- continue;
- }
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,38)
- if (sk_run_filter(skb, fi->filter) == 0)
- continue;
-#else
- if (sk_run_filter(skb, fi->filter, fi->hdr.n_items) == 0)
- continue;
-#endif
-
- found = true;
- break;
- }
- if (!found && def >= 0) {
- j = def;
- found = true;
- }
- if (found) {
- struct wprobe_filter_counter *c = &fg->counters[j];
-
- if (hdr->type >= WPROBE_PKT_TX)
- c->tx++;
- else
- c->rx++;
- }
- }
-
- spin_unlock_irqrestore(&f->lock, flags);
-out:
- rcu_read_unlock();
- return 0;
-}
-EXPORT_SYMBOL(wprobe_add_frame);
-
-static int
-wprobe_sync_data(struct wprobe_iface *dev, struct wprobe_link *l, bool query)
-{
- struct wprobe_value *val;
- unsigned long flags;
- int n, err;
-
- if (l) {
- n = dev->n_link_items;
- val = l->val;
- } else {
- n = dev->n_global_items;
- val = dev->val;
- }
-
- spin_lock_irqsave(&dev->lock, flags);
- err = dev->sync_data(dev, l, val, !query);
- if (err)
- goto done;
-
- if (query)
- memcpy(dev->query_val, val, sizeof(struct wprobe_value) * n);
-
- wprobe_update_stats(dev, l);
-done:
- spin_unlock_irqrestore(&dev->lock, flags);
- return 0;
-}
-EXPORT_SYMBOL(wprobe_sync_data);
-
-static void
-wprobe_scale_stats(struct wprobe_iface *dev, const struct wprobe_item *item,
- struct wprobe_value *val, int n)
-{
- u64 scale_ts = jiffies_64;
- int i;
-
- for (i = 0; i < n; i++) {
- if (!(item[i].flags & WPROBE_F_KEEPSTAT))
- continue;
-
- if (val[i].n <= dev->scale_min)
- continue;
-
- /* FIXME: div_s64 seems to be very imprecise here, even when
- * the values are scaled up */
- val[i].s *= dev->scale_m;
- val[i].s = div_s64(val[i].s, dev->scale_d);
-
- val[i].ss *= dev->scale_m;
- val[i].ss = div_s64(val[i].ss, dev->scale_d);
-
- val[i].n = (val[i].n * dev->scale_m) / dev->scale_d;
- val[i].scale_timestamp = scale_ts;
- }
-}
-
-
-void
-wprobe_update_stats(struct wprobe_iface *dev, struct wprobe_link *l)
-{
- const struct wprobe_item *item;
- struct wprobe_value *val;
- bool scale_stats = false;
- int i, n;
-
- if (l) {
- n = dev->n_link_items;
- item = dev->link_items;
- val = l->val;
- } else {
- n = dev->n_global_items;
- item = dev->global_items;
- val = dev->val;
- }
-
- /* process statistics */
- for (i = 0; i < n; i++) {
- s64 v;
-
- if (!val[i].pending)
- continue;
-
- val[i].n++;
- if ((item[i].flags & WPROBE_F_KEEPSTAT) &&
- (dev->scale_max > 0) && (val[i].n > dev->scale_max)) {
- scale_stats = true;
- }
-
- switch(item[i].type) {
- case WPROBE_VAL_S8:
- v = val[i].S8;
- break;
- case WPROBE_VAL_S16:
- v = val[i].S16;
- break;
- case WPROBE_VAL_S32:
- v = val[i].S32;
- break;
- case WPROBE_VAL_S64:
- v = val[i].S64;
- break;
- case WPROBE_VAL_U8:
- v = val[i].U8;
- break;
- case WPROBE_VAL_U16:
- v = val[i].U16;
- break;
- case WPROBE_VAL_U32:
- v = val[i].U32;
- break;
- case WPROBE_VAL_U64:
- v = val[i].U64;
- break;
- default:
- continue;
- }
-
- val[i].s += v;
- val[i].ss += v * v;
- val[i].pending = false;
- }
- if (scale_stats)
- wprobe_scale_stats(dev, item, val, n);
-}
-EXPORT_SYMBOL(wprobe_update_stats);
-
-static const struct nla_policy wprobe_policy[WPROBE_ATTR_LAST+1] = {
- [WPROBE_ATTR_INTERFACE] = { .type = NLA_NUL_STRING },
- [WPROBE_ATTR_MAC] = { .type = NLA_STRING },
- [WPROBE_ATTR_FLAGS] = { .type = NLA_U32 },
-
- /* config */
- [WPROBE_ATTR_INTERVAL] = { .type = NLA_MSECS },
- [WPROBE_ATTR_SAMPLES_MIN] = { .type = NLA_U32 },
- [WPROBE_ATTR_SAMPLES_MAX] = { .type = NLA_U32 },
- [WPROBE_ATTR_SAMPLES_SCALE_M] = { .type = NLA_U32 },
- [WPROBE_ATTR_SAMPLES_SCALE_D] = { .type = NLA_U32 },
- [WPROBE_ATTR_FILTER] = { .type = NLA_BINARY, .len = 32768 },
-};
-
-static bool
-wprobe_check_ptr(struct list_head *list, struct list_head *ptr)
-{
- struct list_head *p;
-
- list_for_each_rcu(p, list) {
- if (ptr == p)
- return true;
- }
- return false;
-}
-
-static bool
-wprobe_send_item_value(struct sk_buff *msg, struct netlink_callback *cb,
- struct wprobe_iface *dev, struct wprobe_link *l,
- const struct wprobe_item *item,
- int i, u32 flags)
-{
- struct genlmsghdr *hdr;
- struct wprobe_value *val = dev->query_val;
- u64 time = val[i].last - val[i].first;
-
- hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
- &wprobe_fam, NLM_F_MULTI, WPROBE_CMD_GET_INFO);
-
- NLA_PUT_U32(msg, WPROBE_ATTR_ID, i);
- NLA_PUT_U32(msg, WPROBE_ATTR_FLAGS, flags);
- NLA_PUT_U8(msg, WPROBE_ATTR_TYPE, item[i].type);
- NLA_PUT_U64(msg, WPROBE_ATTR_DURATION, time);
-
- switch(item[i].type) {
- case WPROBE_VAL_S8:
- case WPROBE_VAL_U8:
- NLA_PUT_U8(msg, item[i].type, val[i].U8);
- break;
- case WPROBE_VAL_S16:
- case WPROBE_VAL_U16:
- NLA_PUT_U16(msg, item[i].type, val[i].U16);
- break;
- case WPROBE_VAL_S32:
- case WPROBE_VAL_U32:
- NLA_PUT_U32(msg, item[i].type, val[i].U32);
- break;
- case WPROBE_VAL_S64:
- case WPROBE_VAL_U64:
- NLA_PUT_U64(msg, item[i].type, val[i].U64);
- break;
- case WPROBE_VAL_STRING:
- if (val[i].STRING)
- NLA_PUT_STRING(msg, item[i].type, val[i].STRING);
- else
- NLA_PUT_STRING(msg, item[i].type, "");
- /* bypass avg/stdev */
- goto done;
- default:
- /* skip unknown values */
- goto done;
- }
- if (item[i].flags & WPROBE_F_KEEPSTAT) {
- NLA_PUT_U64(msg, WPROBE_VAL_SUM, val[i].s);
- NLA_PUT_U64(msg, WPROBE_VAL_SUM_SQ, val[i].ss);
- NLA_PUT_U32(msg, WPROBE_VAL_SAMPLES, (u32) val[i].n);
- NLA_PUT_MSECS(msg, WPROBE_VAL_SCALE_TIME, val[i].scale_timestamp);
- }
-done:
- genlmsg_end(msg, hdr);
- return true;
-
-nla_put_failure:
- genlmsg_cancel(msg, hdr);
- return false;
-}
-
-static bool
-wprobe_send_item_info(struct sk_buff *msg, struct netlink_callback *cb,
- struct wprobe_iface *dev,
- const struct wprobe_item *item, int i)
-{
- struct genlmsghdr *hdr;
-
- hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
- &wprobe_fam, NLM_F_MULTI, WPROBE_CMD_GET_LIST);
-
- if ((i == 0) && (dev->addr != NULL))
- NLA_PUT(msg, WPROBE_ATTR_MAC, 6, dev->addr);
- NLA_PUT_U32(msg, WPROBE_ATTR_ID, (u32) i);
- NLA_PUT_STRING(msg, WPROBE_ATTR_NAME, item[i].name);
- NLA_PUT_U8(msg, WPROBE_ATTR_TYPE, item[i].type);
- NLA_PUT_U32(msg, WPROBE_ATTR_FLAGS, item[i].flags);
- genlmsg_end(msg, hdr);
- return true;
-
-nla_put_failure:
- genlmsg_cancel(msg, hdr);
- return false;
-}
-
-
-static struct wprobe_link *
-wprobe_find_link(struct wprobe_iface *dev, const char *mac)
-{
- struct wprobe_link *l;
-
- list_for_each_entry_rcu(l, &dev->links, list) {
- if (!memcmp(l->addr, mac, 6))
- return l;
- }
- return NULL;
-}
-
-static bool
-wprobe_dump_filter_group(struct sk_buff *msg, struct wprobe_filter_group *fg, struct netlink_callback *cb)
-{
- struct genlmsghdr *hdr;
- struct nlattr *group, *item;
- int i;
-
- hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
- &wprobe_fam, NLM_F_MULTI, WPROBE_CMD_GET_FILTER);
- if (!hdr)
- return false;
-
- NLA_PUT_STRING(msg, WPROBE_ATTR_NAME, fg->name);
- group = nla_nest_start(msg, WPROBE_ATTR_FILTER_GROUP);
- for (i = 0; i < fg->n_items; i++) {
- struct wprobe_filter_item *fi = fg->items[i];
- struct wprobe_filter_counter *fc = &fg->counters[i];
-
- item = nla_nest_start(msg, WPROBE_ATTR_FILTER_GROUP);
- NLA_PUT_STRING(msg, WPROBE_ATTR_NAME, fi->hdr.name);
- NLA_PUT_U64(msg, WPROBE_ATTR_RXCOUNT, fc->rx);
- NLA_PUT_U64(msg, WPROBE_ATTR_TXCOUNT, fc->tx);
- nla_nest_end(msg, item);
- }
-
- nla_nest_end(msg, group);
- genlmsg_end(msg, hdr);
- return true;
-
-nla_put_failure:
- genlmsg_cancel(msg, hdr);
- return false;
-}
-
-static int
-wprobe_dump_filters(struct sk_buff *skb, struct netlink_callback *cb)
-{
- struct wprobe_iface *dev = (struct wprobe_iface *)cb->args[0];
- struct wprobe_filter *f;
- int err = 0;
- int i = 0;
-
- if (!dev) {
- err = nlmsg_parse(cb->nlh, GENL_HDRLEN + wprobe_fam.hdrsize,
- wprobe_fam.attrbuf, wprobe_fam.maxattr, wprobe_policy);
- if (err)
- goto done;
-
- dev = wprobe_get_dev(wprobe_fam.attrbuf[WPROBE_ATTR_INTERFACE]);
- if (!dev) {
- err = -ENODEV;
- goto done;
- }
-
- cb->args[0] = (long) dev;
- cb->args[1] = 0;
- } else {
- if (!wprobe_check_ptr(&wprobe_if, &dev->list)) {
- err = -ENODEV;
- goto done;
- }
- }
-
- rcu_read_lock();
- f = rcu_dereference(dev->active_filter);
- if (!f)
- goto abort;
-
- for (i = cb->args[1]; i < f->n_groups; i++) {
- if (unlikely(!wprobe_dump_filter_group(skb, &f->groups[i], cb)))
- break;
- }
- cb->args[1] = i;
-abort:
- rcu_read_unlock();
- err = skb->len;
-done:
- return err;
-}
-
-static bool
-wprobe_dump_link(struct sk_buff *msg, struct wprobe_link *l, struct netlink_callback *cb)
-{
- struct genlmsghdr *hdr;
-
- hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
- &wprobe_fam, NLM_F_MULTI, WPROBE_CMD_GET_LINKS);
- if (!hdr)
- return false;
-
- NLA_PUT(msg, WPROBE_ATTR_MAC, 6, l->addr);
- genlmsg_end(msg, hdr);
- return true;
-
-nla_put_failure:
- genlmsg_cancel(msg, hdr);
- return false;
-}
-
-static int
-wprobe_dump_links(struct sk_buff *skb, struct netlink_callback *cb)
-{
- struct wprobe_iface *dev = (struct wprobe_iface *)cb->args[0];
- struct wprobe_link *l;
- int err = 0;
- int i = 0;
-
- if (!dev) {
- err = nlmsg_parse(cb->nlh, GENL_HDRLEN + wprobe_fam.hdrsize,
- wprobe_fam.attrbuf, wprobe_fam.maxattr, wprobe_policy);
- if (err)
- goto done;
-
- dev = wprobe_get_dev(wprobe_fam.attrbuf[WPROBE_ATTR_INTERFACE]);
- if (!dev) {
- err = -ENODEV;
- goto done;
- }
-
- cb->args[0] = (long) dev;
- } else {
- if (!wprobe_check_ptr(&wprobe_if, &dev->list)) {
- err = -ENODEV;
- goto done;
- }
- }
-
- rcu_read_lock();
- list_for_each_entry_rcu(l, &dev->links, list) {
- if (i < cb->args[1])
- continue;
-
- if (unlikely(!wprobe_dump_link(skb, l, cb)))
- break;
-
- i++;
- }
- cb->args[1] = i;
- rcu_read_unlock();
- err = skb->len;
-done:
- return err;
-}
-
-#define WPROBE_F_LINK (1 << 31) /* for internal use */
-static int
-wprobe_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
-{
- struct wprobe_iface *dev = (struct wprobe_iface *)cb->args[0];
- struct wprobe_link *l = (struct wprobe_link *)cb->args[1];
- struct wprobe_value *val;
- const struct wprobe_item *item;
- struct genlmsghdr *hdr;
- unsigned long flags;
- int cmd, n, i = cb->args[3];
- u32 vflags = cb->args[2];
- int err = 0;
-
- hdr = (struct genlmsghdr *)nlmsg_data(cb->nlh);
- cmd = hdr->cmd;
-
- /* since the attribute value list might be too big for a single netlink
- * message, the device, link and offset get stored in the netlink callback.
- * if this is the first request, we need to do the full lookup for the device.
- *
- * access to the device and link structure is synchronized through rcu.
- */
- rcu_read_lock();
- if (!dev) {
- err = nlmsg_parse(cb->nlh, GENL_HDRLEN + wprobe_fam.hdrsize,
- wprobe_fam.attrbuf, wprobe_fam.maxattr, wprobe_policy);
- if (err)
- goto done;
-
- err = -ENOENT;
- dev = wprobe_get_dev(wprobe_fam.attrbuf[WPROBE_ATTR_INTERFACE]);
- if (!dev)
- goto done;
-
- if (cmd == WPROBE_CMD_GET_INFO) {
- if (wprobe_fam.attrbuf[WPROBE_ATTR_MAC]) {
- l = wprobe_find_link(dev, nla_data(wprobe_fam.attrbuf[WPROBE_ATTR_MAC]));
- if (!l)
- goto done;
-
- vflags = l->flags;
- }
-
- if (l) {
- item = dev->link_items;
- n = dev->n_link_items;
- val = l->val;
- } else {
- item = dev->global_items;
- n = dev->n_global_items;
- val = dev->val;
- }
-
- /* sync data and move to temp storage for the query */
- spin_lock_irqsave(&dev->lock, flags);
- err = wprobe_sync_data(dev, l, true);
- if (!err)
- memcpy(dev->query_val, val, n * sizeof(struct wprobe_value));
- spin_unlock_irqrestore(&dev->lock, flags);
-
- if (err)
- goto done;
- }
-
- if (wprobe_fam.attrbuf[WPROBE_ATTR_FLAGS])
- vflags |= nla_get_u32(wprobe_fam.attrbuf[WPROBE_ATTR_FLAGS]);
-
- if (wprobe_fam.attrbuf[WPROBE_ATTR_MAC])
- vflags |= WPROBE_F_LINK;
-
- cb->args[0] = (long) dev;
- cb->args[1] = (long) l;
- cb->args[2] = vflags;
- cb->args[3] = 0;
- } else {
- /* when pulling pointers from the callback, validate them
- * against the list using rcu to make sure that we won't
- * dereference pointers to free'd memory after the last
- * grace period */
- err = -ENOENT;
- if (!wprobe_check_ptr(&wprobe_if, &dev->list))
- goto done;
-
- if (l && !wprobe_check_ptr(&dev->links, &l->list))
- goto done;
- }
-
- if (vflags & WPROBE_F_LINK) {
- item = dev->link_items;
- n = dev->n_link_items;
- } else {
- item = dev->global_items;
- n = dev->n_global_items;
- }
-
- err = 0;
- switch(cmd) {
- case WPROBE_CMD_GET_INFO:
- while (i < n) {
- if (!wprobe_send_item_value(skb, cb, dev, l, item, i, vflags))
- break;
- i++;
- }
- break;
- case WPROBE_CMD_GET_LIST:
- while (i < n) {
- if (!wprobe_send_item_info(skb, cb, dev, item, i))
- break;
- i++;
- }
- break;
- default:
- err = -EINVAL;
- goto done;
- }
- cb->args[3] = i;
- err = skb->len;
-
-done:
- rcu_read_unlock();
- return err;
-}
-#undef WPROBE_F_LINK
-
-static int
-wprobe_update_auto_measurement(struct wprobe_iface *dev, u32 interval)
-{
- if (interval && (interval < WPROBE_MIN_INTERVAL))
- return -EINVAL;
-
- if (!interval && dev->measure_interval)
- del_timer_sync(&dev->measure_timer);
-
- dev->measure_interval = interval;
- if (!interval)
- return 0;
-
- /* kick of a new measurement immediately */
- mod_timer(&dev->measure_timer, jiffies + 1);
-
- return 0;
-}
-
-static int
-wprobe_measure(struct sk_buff *skb, struct genl_info *info)
-{
- struct wprobe_iface *dev;
- struct wprobe_link *l = NULL;
- int err = -ENOENT;
-
- rcu_read_lock();
- dev = wprobe_get_dev(info->attrs[WPROBE_ATTR_INTERFACE]);
- if (!dev)
- goto done;
-
- if (info->attrs[WPROBE_ATTR_MAC]) {
- l = wprobe_find_link(dev, nla_data(wprobe_fam.attrbuf[WPROBE_ATTR_MAC]));
- if (!l)
- goto done;
- }
-
- err = wprobe_sync_data(dev, l, false);
-
-done:
- rcu_read_unlock();
- return err;
-}
-
-static int
-wprobe_check_filter(void *data, int datalen, int gs)
-{
- struct wprobe_filter_item_hdr *hdr;
- void *orig_data = data;
- void *end = data + datalen;
- int i, j, k, is, cur_is;
-
- for (i = j = is = 0; i < gs; i++) {
- hdr = data;
- data += sizeof(*hdr);
-
- if (data > end)
- goto overrun;
-
- hdr->name[31] = 0;
- cur_is = be32_to_cpu(hdr->n_items);
- hdr->n_items = cur_is;
- is += cur_is;
- for (j = 0; j < cur_is; j++) {
- struct sock_filter *sf;
- int n_items;
-
- hdr = data;
- data += sizeof(*hdr);
- if (data > end)
- goto overrun;
-
- hdr->name[31] = 0;
- n_items = be32_to_cpu(hdr->n_items);
- hdr->n_items = n_items;
-
- if (n_items > 1024)
- goto overrun;
-
- sf = data;
- if (n_items > 0) {
- for (k = 0; k < n_items; k++) {
- sf->code = be16_to_cpu(sf->code);
- sf->k = be32_to_cpu(sf->k);
- sf++;
- }
- if (sk_chk_filter(data, n_items) != 0) {
- printk("%s: filter check failed at group %d, item %d\n", __func__, i, j);
- return 0;
- }
- }
- data += n_items * sizeof(struct sock_filter);
- }
- }
- return is;
-
-overrun:
- printk(KERN_ERR "%s: overrun during filter check at group %d, item %d, offset=%d, len=%d\n", __func__, i, j, (data - orig_data), datalen);
- return 0;
-}
-
-static void
-wprobe_free_filter(struct wprobe_filter *f)
-{
- if (f->skb)
- kfree_skb(f->skb);
- if (f->data)
- kfree(f->data);
- if (f->items)
- kfree(f->items);
- if (f->counters)
- kfree(f->counters);
- kfree(f);
-}
-
-
-static int
-wprobe_set_filter(struct wprobe_iface *dev, void *data, int len)
-{
- struct wprobe_filter_hdr *fhdr;
- struct wprobe_rtap_hdr *rtap;
- struct wprobe_filter *f;
- int i, j, cur_is, is, gs;
-
- if (len < sizeof(*fhdr))
- return -EINVAL;
-
- fhdr = data;
- data += sizeof(*fhdr);
- len -= sizeof(*fhdr);
-
- if (memcmp(fhdr->magic, "WPFF", 4) != 0) {
- printk(KERN_ERR "%s: filter rejected (invalid magic)\n", __func__);
- return -EINVAL;
- }
-
- gs = be16_to_cpu(fhdr->n_groups);
- is = wprobe_check_filter(data, len, gs);
- if (is == 0)
- return -EINVAL;
-
- f = kzalloc(sizeof(struct wprobe_filter) +
- gs * sizeof(struct wprobe_filter_group), GFP_ATOMIC);
- if (!f)
- return -ENOMEM;
-
- f->skb = alloc_skb(WPROBE_MAX_FRAME_SIZE, GFP_ATOMIC);
- if (!f->skb)
- goto error;
-
- f->data = kmalloc(len, GFP_ATOMIC);
- if (!f->data)
- goto error;
-
- f->items = kzalloc(sizeof(struct wprobe_filter_item *) * is, GFP_ATOMIC);
- if (!f->items)
- goto error;
-
- f->counters = kzalloc(sizeof(struct wprobe_filter_counter) * is, GFP_ATOMIC);
- if (!f->counters)
- goto error;
-
- spin_lock_init(&f->lock);
- memcpy(f->data, data, len);
- f->n_groups = gs;
-
- if (f->hdrlen < sizeof(struct wprobe_wlan_hdr))
- f->hdrlen = sizeof(struct wprobe_wlan_hdr);
-
- rtap = (struct wprobe_rtap_hdr *)skb_put(f->skb, sizeof(*rtap));
- memset(rtap, 0, sizeof(*rtap));
- rtap->len = cpu_to_le16(sizeof(struct wprobe_rtap_hdr) + f->hdrlen);
- data = f->data;
-
- cur_is = 0;
- for (i = 0; i < gs; i++) {
- struct wprobe_filter_item_hdr *hdr = data;
- struct wprobe_filter_group *g = &f->groups[i];
-
- data += sizeof(*hdr);
- g->name = hdr->name;
- g->items = &f->items[cur_is];
- g->counters = &f->counters[cur_is];
- g->n_items = hdr->n_items;
-
- for (j = 0; j < g->n_items; j++) {
- hdr = data;
- f->items[cur_is++] = data;
- data += sizeof(*hdr) + hdr->n_items * sizeof(struct sock_filter);
- }
- }
- rcu_assign_pointer(dev->active_filter, f);
- return 0;
-
-error:
- wprobe_free_filter(f);
- return -ENOMEM;
-}
-
-static int
-wprobe_set_config(struct sk_buff *skb, struct genl_info *info)
-{
- struct wprobe_iface *dev;
- unsigned long flags;
- int err = -ENOENT;
- u32 scale_min, scale_max;
- u32 scale_m, scale_d;
- struct nlattr *attr;
- struct wprobe_filter *filter_free = NULL;
-
- rcu_read_lock();
- dev = wprobe_get_dev(info->attrs[WPROBE_ATTR_INTERFACE]);
- if (!dev)
- goto done_unlocked;
-
- err = -EINVAL;
- spin_lock_irqsave(&dev->lock, flags);
- if (info->attrs[WPROBE_ATTR_MAC]) {
- /* not supported yet */
- goto done;
- }
-
- if (info->attrs[WPROBE_ATTR_FLAGS]) {
- u32 flags = nla_get_u32(info->attrs[WPROBE_ATTR_FLAGS]);
-
- if (flags & BIT(WPROBE_F_RESET)) {
- struct wprobe_link *l;
-
- memset(dev->val, 0, sizeof(struct wprobe_value) * dev->n_global_items);
- list_for_each_entry_rcu(l, &dev->links, list) {
- memset(l->val, 0, sizeof(struct wprobe_value) * dev->n_link_items);
- }
- }
- }
-
- if (info->attrs[WPROBE_ATTR_SAMPLES_MIN] ||
- info->attrs[WPROBE_ATTR_SAMPLES_MAX]) {
- if ((attr = info->attrs[WPROBE_ATTR_SAMPLES_MIN]))
- scale_min = nla_get_u32(attr);
- else
- scale_min = dev->scale_min;
-
- if ((attr = info->attrs[WPROBE_ATTR_SAMPLES_MAX]))
- scale_max = nla_get_u32(attr);
- else
- scale_max = dev->scale_max;
-
- if ((!scale_min && !scale_max) ||
- (scale_min && scale_max && (scale_min < scale_max))) {
- dev->scale_min = scale_min;
- dev->scale_max = scale_max;
- } else {
- goto done;
- }
- }
-
- if (info->attrs[WPROBE_ATTR_SAMPLES_SCALE_M] &&
- info->attrs[WPROBE_ATTR_SAMPLES_SCALE_D]) {
-
- scale_m = nla_get_u32(info->attrs[WPROBE_ATTR_SAMPLES_SCALE_M]);
- scale_d = nla_get_u32(info->attrs[WPROBE_ATTR_SAMPLES_SCALE_D]);
-
- if (!scale_d || (scale_m > scale_d))
- goto done;
-
- dev->scale_m = scale_m;
- dev->scale_d = scale_d;
- }
-
- if ((attr = info->attrs[WPROBE_ATTR_FILTER])) {
- filter_free = rcu_dereference(dev->active_filter);
- rcu_assign_pointer(dev->active_filter, NULL);
- if (nla_len(attr) > 0)
- wprobe_set_filter(dev, nla_data(attr), nla_len(attr));
- }
-
- err = 0;
- if (info->attrs[WPROBE_ATTR_INTERVAL]) {
- /* change of measurement interval requested */
- err = wprobe_update_auto_measurement(dev,
- (u32) nla_get_u64(info->attrs[WPROBE_ATTR_INTERVAL]));
- }
-
-done:
- spin_unlock_irqrestore(&dev->lock, flags);
-done_unlocked:
- rcu_read_unlock();
- if (filter_free) {
- synchronize_rcu();
- wprobe_free_filter(filter_free);
- }
- return err;
-}
-
-static struct genl_ops wprobe_ops[] = {
- {
- .cmd = WPROBE_CMD_GET_INFO,
- .dumpit = wprobe_dump_info,
- .policy = wprobe_policy,
- },
- {
- .cmd = WPROBE_CMD_GET_LIST,
- .dumpit = wprobe_dump_info,
- .policy = wprobe_policy,
- },
- {
- .cmd = WPROBE_CMD_MEASURE,
- .doit = wprobe_measure,
- .policy = wprobe_policy,
- },
- {
- .cmd = WPROBE_CMD_GET_LINKS,
- .dumpit = wprobe_dump_links,
- .policy = wprobe_policy,
- },
- {
- .cmd = WPROBE_CMD_CONFIG,
- .doit = wprobe_set_config,
- .policy = wprobe_policy,
- },
- {
- .cmd = WPROBE_CMD_GET_FILTER,
- .dumpit = wprobe_dump_filters,
- .policy = wprobe_policy,
- },
-};
-
-static void __exit
-wprobe_exit(void)
-{
- BUG_ON(!list_empty(&wprobe_if));
- genl_unregister_family(&wprobe_fam);
-}
-
-
-static int __init
-wprobe_init(void)
-{
- int i, err;
-
- spin_lock_init(&wprobe_lock);
- INIT_LIST_HEAD(&wprobe_if);
-
- err = genl_register_family(&wprobe_fam);
- if (err)
- return err;
-
- for (i = 0; i < ARRAY_SIZE(wprobe_ops); i++) {
- err = genl_register_ops(&wprobe_fam, &wprobe_ops[i]);
- if (err)
- goto error;
- }
-
- return 0;
-
-error:
- genl_unregister_family(&wprobe_fam);
- return err;
-}
-
-module_init(wprobe_init);
-module_exit(wprobe_exit);
-MODULE_LICENSE("GPL");
-
projects / openwrt / staging / florian.git / blobdiff