X-Git-Url: https://git.rohieb.name/openwrt.git/blobdiff_plain/ab6bc07067a65ba7ea2795045083eb9559c68fb1..6b20955cca6fb3518c4d77afb68938749fdf3201:/package/wprobe/src/kernel/wprobe-core.c?ds=sidebyside diff --git a/package/wprobe/src/kernel/wprobe-core.c b/package/wprobe/src/kernel/wprobe-core.c index 798cd7dde..68d07172a 100644 --- a/package/wprobe/src/kernel/wprobe-core.c +++ b/package/wprobe/src/kernel/wprobe-core.c @@ -31,9 +31,16 @@ #define static #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,28) -#define list_for_each_rcu __list_for_each_rcu +#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; @@ -43,10 +50,20 @@ static struct genl_family wprobe_fam = { .hdrsize = 0, .version = 1, /* only the first set of attributes is used for queries */ - .maxattr = WPROBE_ATTR_ID, + .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) @@ -81,6 +98,19 @@ wprobe_remove_link(struct wprobe_iface *s, struct wprobe_link *l) } 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) { @@ -93,16 +123,26 @@ wprobe_add_iface(struct wprobe_iface *s) 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); - vsize = max(s->n_link_items, s->n_global_items); - s->val = kzalloc(sizeof(struct wprobe_value) * vsize, GFP_ATOMIC); + 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); @@ -123,6 +163,7 @@ wprobe_remove_iface(struct wprobe_iface *s) 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); @@ -133,6 +174,8 @@ wprobe_remove_iface(struct wprobe_iface *s) kfree(s->val); kfree(s->query_val); + if (s->active_filter) + wprobe_free_filter(s->active_filter); } EXPORT_SYMBOL(wprobe_remove_iface); @@ -161,6 +204,73 @@ wprobe_get_dev(struct nlattr *attr) } 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 (sk_run_filter(skb, fi->filter, fi->hdr.n_items) == 0) + continue; + + 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; @@ -190,11 +300,40 @@ done: } 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) { @@ -215,6 +354,10 @@ wprobe_update_stats(struct wprobe_iface *dev, struct wprobe_link *l) 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: @@ -249,15 +392,23 @@ wprobe_update_stats(struct wprobe_iface *dev, struct wprobe_link *l) 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_ID+1] = { +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_DURATION] = { .type = NLA_MSECS }, [WPROBE_ATTR_FLAGS] = { .type = NLA_U32 }, - [WPROBE_ATTR_SCALE] = { .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 @@ -322,6 +473,7 @@ wprobe_send_item_value(struct sk_buff *msg, struct netlink_callback *cb, 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); @@ -369,6 +521,86 @@ wprobe_find_link(struct wprobe_iface *dev, const char *mac) 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) { @@ -432,29 +664,6 @@ wprobe_dump_links(struct sk_buff *skb, struct netlink_callback *cb) done: return err; } -static void -wprobe_scale_stats(const struct wprobe_item *item, struct wprobe_value *val, int n, u32 flags) -{ - u32 scale = 0; - int i; - - for (i = 0; i < n; i++) { - if (!(item[i].flags & WPROBE_F_KEEPSTAT)) - continue; - - /* reset statistics, if requested */ - if (flags & WPROBE_F_RESET) - scale = val[i].n; - else if (wprobe_fam.attrbuf[WPROBE_ATTR_SCALE]) - scale = nla_get_u32(wprobe_fam.attrbuf[WPROBE_ATTR_SCALE]); - - if ((scale > 0) && (val[i].n > scale)) { - val[i].s = div_s64(val[i].s, scale); - val[i].ss = div_s64(val[i].ss, scale); - val[i].n = val[i].n / scale + 1; - } - } -} #define WPROBE_F_LINK (1 << 31) /* for internal use */ static int @@ -515,7 +724,6 @@ wprobe_dump_info(struct sk_buff *skb, struct netlink_callback *cb) err = wprobe_sync_data(dev, l, true); if (!err) memcpy(dev->query_val, val, n * sizeof(struct wprobe_value)); - wprobe_scale_stats(item, val, n, flags); spin_unlock_irqrestore(&dev->lock, flags); if (err) @@ -582,6 +790,25 @@ done: } #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) { @@ -607,6 +834,256 @@ done: 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, @@ -627,7 +1104,17 @@ static struct genl_ops wprobe_ops[] = { .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