add wireless measurement probe infrastructure, developed at Fraunhofer FOKUS

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@15050 3c298f89-4303-0410-b956-a3cf2f4a3e73

1 files changed, 472 insertions, 0 deletions

diff --git a/package/wprobe/src/user/wprobe.c b/package/wprobe/src/user/wprobe.c
new file mode 100644
index 0000000000..d591207daf
--- /dev/null
+++ b/package/wprobe/src/user/wprobe.c
@@ -0,0 +1,472 @@
+/*
+ * wprobe.c: Wireless probe user space library
+ * 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 <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <getopt.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <math.h>
+#include <linux/wprobe.h>
+#include <netlink/netlink.h>
+#include <netlink/genl/genl.h>
+#include <netlink/genl/ctrl.h>
+#include <netlink/genl/family.h>
+#include "wprobe.h"
+
+#define DEBUG 1
+#ifdef DEBUG
+#define DPRINTF(fmt, ...) fprintf(stderr, "%s(%d): " fmt, __func__, __LINE__, ##__VA_ARGS__)
+#else
+#define DPRINTF(fmt, ...) do {} while (0)
+#endif
+
+static struct nl_handle *handle = NULL;
+static struct nl_cache *cache = NULL;
+static struct genl_family *family = NULL;
+static struct nlattr *tb[WPROBE_ATTR_LAST+1];
+static struct nla_policy attribute_policy[WPROBE_ATTR_LAST+1] = {
+	[WPROBE_ATTR_ID] = { .type = NLA_U32 },
+	[WPROBE_ATTR_MAC] = { .type = NLA_UNSPEC, .minlen = 6, .maxlen = 6 },
+	[WPROBE_ATTR_NAME] = { .type = NLA_STRING },
+	[WPROBE_ATTR_FLAGS] = { .type = NLA_U32 },
+	[WPROBE_ATTR_TYPE] = { .type = NLA_U8 },
+	[WPROBE_VAL_S8] = { .type = NLA_U8 },
+	[WPROBE_VAL_S16] = { .type = NLA_U16 },
+	[WPROBE_VAL_S32] = { .type = NLA_U32 },
+	[WPROBE_VAL_S64] = { .type = NLA_U64 },
+	[WPROBE_VAL_U8] = { .type = NLA_U8 },
+	[WPROBE_VAL_U16] = { .type = NLA_U16 },
+	[WPROBE_VAL_U32] = { .type = NLA_U32 },
+	[WPROBE_VAL_U64] = { .type = NLA_U64 },
+	[WPROBE_VAL_SUM] = { .type = NLA_U64 },
+	[WPROBE_VAL_SUM_SQ] = { .type = NLA_U64 },
+	[WPROBE_VAL_SAMPLES] = { .type = NLA_U32 },
+};
+
+static int
+error_handler(struct sockaddr_nl *nla, struct nlmsgerr *err, void *arg)
+{
+	int *ret = arg;
+	*ret = err->error;
+	return NL_STOP;
+}
+
+static int
+finish_handler(struct nl_msg *msg, void *arg)
+{
+	int *ret = arg;
+	*ret = 0;
+	return NL_SKIP;
+}
+
+static int
+ack_handler(struct nl_msg *msg, void *arg)
+{
+	int *ret = arg;
+	*ret = 0;
+	return NL_STOP;
+}
+
+
+void
+wprobe_free(void)
+{
+	if (cache)
+		nl_cache_free(cache);
+	if (handle)
+		nl_handle_destroy(handle);
+	handle = NULL;
+	cache = NULL;
+}
+
+int
+wprobe_init(void)
+{
+	handle = nl_handle_alloc();
+	if (!handle) {
+		DPRINTF("Failed to create handle\n");
+		goto err;
+	}
+
+	if (genl_connect(handle)) {
+		DPRINTF("Failed to connect to generic netlink\n");
+		goto err;
+	}
+
+	cache = genl_ctrl_alloc_cache(handle);
+	if (!cache) {
+		DPRINTF("Failed to allocate netlink cache\n");
+		goto err;
+	}
+
+	family = genl_ctrl_search_by_name(cache, "wprobe");
+	if (!family) {
+		DPRINTF("wprobe API not present\n");
+		goto err;
+	}
+	return 0;
+
+err:
+	wprobe_free();
+	return -EINVAL;
+}
+
+
+static struct nl_msg *
+wprobe_new_msg(const char *ifname, int cmd, bool dump)
+{
+	struct nl_msg *msg;
+	uint32_t flags = 0;
+
+	msg = nlmsg_alloc();
+	if (!msg)
+		return NULL;
+
+	if (dump)
+		flags |= NLM_F_DUMP;
+
+	genlmsg_put(msg, 0, 0, genl_family_get_id(family),
+			0, flags, cmd, 0);
+
+	NLA_PUT_STRING(msg, WPROBE_ATTR_INTERFACE, ifname);
+nla_put_failure:
+	return msg;
+}
+
+static int
+wprobe_send_msg(struct nl_msg *msg, void *callback, void *arg)
+{
+	struct nl_cb *cb;
+	int err = 0;
+
+	cb = nl_cb_alloc(NL_CB_DEFAULT);
+	if (!cb)
+		goto out_no_cb;
+
+	if (callback)
+		nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, callback, arg);
+
+	err = nl_send_auto_complete(handle, msg);
+	if (err < 0)
+		goto out;
+
+	err = 1;
+
+	nl_cb_err(cb, NL_CB_CUSTOM, error_handler, &err);
+	nl_cb_set(cb, NL_CB_FINISH, NL_CB_CUSTOM, finish_handler, &err);
+	nl_cb_set(cb, NL_CB_ACK, NL_CB_CUSTOM, ack_handler, &err);
+
+	while (err > 0)
+		nl_recvmsgs(handle, cb);
+
+out:
+	nl_cb_put(cb);
+out_no_cb:
+	nlmsg_free(msg);
+	return err;
+}
+
+struct wprobe_attr_cb {
+	struct list_head *list;
+	char *addr;
+};
+
+static int
+save_attribute_handler(struct nl_msg *msg, void *arg)
+{
+	struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
+	const char *name = "N/A";
+	struct wprobe_attribute *attr;
+	int type = 0;
+	struct wprobe_attr_cb *cb = arg;
+
+	nla_parse(tb, WPROBE_ATTR_LAST, genlmsg_attrdata(gnlh, 0),
+			genlmsg_attrlen(gnlh, 0), attribute_policy);
+
+	if (tb[WPROBE_ATTR_NAME])
+		name = nla_data(tb[WPROBE_ATTR_NAME]);
+
+	attr = malloc(sizeof(struct wprobe_attribute) + strlen(name) + 1);
+	if (!attr)
+		return -1;
+
+	memset(attr, 0, sizeof(struct wprobe_attribute));
+
+	if (tb[WPROBE_ATTR_ID])
+		attr->id = nla_get_u32(tb[WPROBE_ATTR_ID]);
+
+	if (tb[WPROBE_ATTR_MAC] && cb->addr)
+		memcpy(cb->addr, nla_data(tb[WPROBE_ATTR_MAC]), 6);
+
+	if (tb[WPROBE_ATTR_FLAGS])
+		attr->flags = nla_get_u32(tb[WPROBE_ATTR_FLAGS]);
+
+	if (tb[WPROBE_ATTR_TYPE])
+		type = nla_get_u8(tb[WPROBE_ATTR_TYPE]);
+
+	if ((type < WPROBE_VAL_STRING) ||
+		(type > WPROBE_VAL_U64))
+		type = 0;
+
+	attr->type = type;
+	strcpy(attr->name, name);
+	INIT_LIST_HEAD(&attr->list);
+	list_add(&attr->list, cb->list);
+	return 0;
+}
+
+
+int
+wprobe_dump_attributes(const char *ifname, bool link, struct list_head *list, char *addr)
+{
+	struct nl_msg *msg;
+	struct wprobe_attr_cb cb;
+
+	cb.list = list;
+	cb.addr = addr;
+	msg = wprobe_new_msg(ifname, WPROBE_CMD_GET_LIST, true);
+	if (!msg)
+		return -ENOMEM;
+
+	if (link)
+		NLA_PUT(msg, WPROBE_ATTR_MAC, 6, "\x00\x00\x00\x00\x00\x00");
+
+	return wprobe_send_msg(msg, save_attribute_handler, &cb);
+
+nla_put_failure:
+	nlmsg_free(msg);
+	return -EINVAL;
+}
+
+static struct wprobe_link *
+get_link(struct list_head *list, const char *addr)
+{
+	struct wprobe_link *l;
+
+	list_for_each_entry(l, list, list) {
+		if (!memcmp(l->addr, addr, 6)) {
+			list_del_init(&l->list);
+			goto out;
+		}
+	}
+
+	/* no previous link found, allocate a new one */
+	l = malloc(sizeof(struct wprobe_link));
+	if (!l)
+		goto out;
+
+	memset(l, 0, sizeof(struct wprobe_link));
+	memcpy(l->addr, addr, sizeof(l->addr));
+	INIT_LIST_HEAD(&l->list);
+
+out:
+	return l;
+}
+
+struct wprobe_save_cb {
+	struct list_head *list;
+	struct list_head old_list;
+};
+
+static int
+save_link_handler(struct nl_msg *msg, void *arg)
+{
+	struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
+	struct wprobe_link *link;
+	struct wprobe_save_cb *cb = arg;
+	const char *addr;
+
+	nla_parse(tb, WPROBE_ATTR_LAST, genlmsg_attrdata(gnlh, 0),
+			genlmsg_attrlen(gnlh, 0), attribute_policy);
+
+	if (!tb[WPROBE_ATTR_MAC] || (nla_len(tb[WPROBE_ATTR_MAC]) != 6))
+		return -1;
+
+	addr = nla_data(tb[WPROBE_ATTR_MAC]);
+	link = get_link(&cb->old_list, addr);
+	if (!link)
+		return -1;
+
+	if (tb[WPROBE_ATTR_FLAGS])
+		link->flags = nla_get_u32(tb[WPROBE_ATTR_FLAGS]);
+
+	list_add_tail(&link->list, cb->list);
+	return 0;
+}
+
+
+int
+wprobe_update_links(const char *ifname, struct list_head *list)
+{
+	struct wprobe_link *l, *tmp;
+	struct nl_msg *msg;
+	struct wprobe_save_cb cb;
+	int err;
+
+	INIT_LIST_HEAD(&cb.old_list);
+	list_splice_init(list, &cb.old_list);
+	cb.list = list;
+
+	msg = wprobe_new_msg(ifname, WPROBE_CMD_GET_LINKS, true);
+	if (!msg)
+		return -ENOMEM;
+
+	err = wprobe_send_msg(msg, save_link_handler, &cb);
+	if (err < 0)
+		return err;
+
+	list_for_each_entry_safe(l, tmp, &cb.old_list, list) {
+		list_del(&l->list);
+		free(l);
+	}
+
+	return 0;
+}
+
+void
+wprobe_measure(const char *ifname)
+{
+	struct nl_msg *msg;
+
+	msg = wprobe_new_msg(ifname, WPROBE_CMD_MEASURE, false);
+	if (!msg)
+		return;
+
+	wprobe_send_msg(msg, NULL, NULL);
+}
+
+struct wprobe_request_cb {
+	struct list_head *list;
+	struct list_head old_list;
+	char *addr;
+};
+
+static int
+save_attrdata_handler(struct nl_msg *msg, void *arg)
+{
+	struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
+	struct wprobe_request_cb *cb = arg;
+	struct wprobe_attribute *attr;
+	int type, id;
+
+	nla_parse(tb, WPROBE_ATTR_LAST, genlmsg_attrdata(gnlh, 0),
+			genlmsg_attrlen(gnlh, 0), attribute_policy);
+
+	if (!tb[WPROBE_ATTR_ID])
+		return -1;
+
+	if (!tb[WPROBE_ATTR_TYPE])
+		return -1;
+
+	id = nla_get_u32(tb[WPROBE_ATTR_ID]);
+	list_for_each_entry(attr, &cb->old_list, list) {
+		if (attr->id == id)
+			goto found;
+	}
+	/* not found */
+	return -1;
+
+found:
+	list_del_init(&attr->list);
+
+	type = nla_get_u8(tb[WPROBE_ATTR_TYPE]);
+	if (type != attr->type) {
+		DPRINTF("WARNING: type mismatch for %s attribute '%s' (%d != %d)\n",
+			(cb->addr ? "link" : "global"),
+			attr->name,
+			type, attr->type);
+		goto out;
+	}
+
+	if ((type < WPROBE_VAL_STRING) ||
+		(type > WPROBE_VAL_U64))
+		goto out;
+
+	memset(&attr->val, 0, sizeof(attr->val));
+
+#define HANDLE_INT_TYPE(_idx, _type) \
+	case WPROBE_VAL_S##_type: \
+	case WPROBE_VAL_U##_type: \
+		attr->val.U##_type = nla_get_u##_type(tb[_idx]); \
+		break
+
+	switch(type) {
+		HANDLE_INT_TYPE(type, 8);
+		HANDLE_INT_TYPE(type, 16);
+		HANDLE_INT_TYPE(type, 32);
+		HANDLE_INT_TYPE(type, 64);
+		case WPROBE_VAL_STRING:
+			/* unimplemented */
+			break;
+	}
+#undef HANDLE_TYPE
+
+	if (attr->flags & WPROBE_F_KEEPSTAT) {
+		if (tb[WPROBE_VAL_SUM])
+			attr->val.s = nla_get_u64(tb[WPROBE_VAL_SUM]);
+
+		if (tb[WPROBE_VAL_SUM_SQ])
+			attr->val.ss = nla_get_u64(tb[WPROBE_VAL_SUM_SQ]);
+
+		if (tb[WPROBE_VAL_SAMPLES])
+			attr->val.n = nla_get_u32(tb[WPROBE_VAL_SAMPLES]);
+
+		if (attr->val.n > 0) {
+			float avg = ((float) attr->val.s) / attr->val.n;
+			float stdev = sqrt((((float) attr->val.ss) / attr->val.n) - (avg * avg));
+			attr->val.avg = avg;
+			attr->val.stdev = stdev;
+		}
+	}
+
+out:
+	list_add_tail(&attr->list, cb->list);
+	return 0;
+}
+
+
+int
+wprobe_request_data(const char *ifname, struct list_head *attrs, const unsigned char *addr, int scale)
+{
+	struct wprobe_request_cb cb;
+	struct nl_msg *msg;
+	int err;
+
+	msg = wprobe_new_msg(ifname, WPROBE_CMD_GET_INFO, true);
+	if (!msg)
+		return -ENOMEM;
+
+	if (scale < 0)
+		NLA_PUT_U32(msg, WPROBE_ATTR_FLAGS, WPROBE_F_RESET);
+	else if (scale > 0)
+		NLA_PUT_U32(msg, WPROBE_ATTR_SCALE, scale);
+
+	if (addr)
+		NLA_PUT(msg, WPROBE_ATTR_MAC, 6, addr);
+
+nla_put_failure:
+	INIT_LIST_HEAD(&cb.old_list);
+	list_splice_init(attrs, &cb.old_list);
+	cb.list = attrs;
+
+	err = wprobe_send_msg(msg, save_attrdata_handler, &cb);
+	list_splice(&cb.old_list, attrs->prev);
+	return err;
+}
+
+