1 files changed, 487 insertions, 0 deletions

diff --git a/contrib/wpa/src/common/gas_server.c b/contrib/wpa/src/common/gas_server.c
new file mode 100644
index 0000000..ca46758
--- /dev/null
+++ b/contrib/wpa/src/common/gas_server.c
@@ -0,0 +1,487 @@
+/*
+ * Generic advertisement service (GAS) server
+ * Copyright (c) 2017, Qualcomm Atheros, Inc.
+ *
+ * This software may be distributed under the terms of the BSD license.
+ * See README for more details.
+ */
+
+#include "includes.h"
+
+#include "utils/common.h"
+#include "utils/list.h"
+#include "utils/eloop.h"
+#include "ieee802_11_defs.h"
+#include "gas.h"
+#include "gas_server.h"
+
+
+#define MAX_ADV_PROTO_ID_LEN 10
+#define GAS_QUERY_TIMEOUT 10
+
+struct gas_server_handler {
+	struct dl_list list;
+	u8 adv_proto_id[MAX_ADV_PROTO_ID_LEN];
+	u8 adv_proto_id_len;
+	struct wpabuf * (*req_cb)(void *ctx, const u8 *sa,
+				  const u8 *query, size_t query_len);
+	void (*status_cb)(void *ctx, struct wpabuf *resp, int ok);
+	void *ctx;
+	struct gas_server *gas;
+};
+
+struct gas_server_response {
+	struct dl_list list;
+	size_t offset;
+	u8 frag_id;
+	struct wpabuf *resp;
+	int freq;
+	u8 dst[ETH_ALEN];
+	u8 dialog_token;
+	struct gas_server_handler *handler;
+};
+
+struct gas_server {
+	struct dl_list handlers; /* struct gas_server_handler::list */
+	struct dl_list responses; /* struct gas_server_response::list */
+	void (*tx)(void *ctx, int freq, const u8 *da, struct wpabuf *resp,
+		   unsigned int wait_time);
+	void *ctx;
+};
+
+static void gas_server_free_response(struct gas_server_response *response);
+
+
+static void gas_server_response_timeout(void *eloop_ctx, void *user_ctx)
+{
+	struct gas_server_response *response = eloop_ctx;
+
+	wpa_printf(MSG_DEBUG, "GAS: Response @%p timeout for " MACSTR
+		   " (dialog_token=%u freq=%d frag_id=%u sent=%lu/%lu) - drop pending data",
+		   response, MAC2STR(response->dst), response->dialog_token,
+		   response->freq, response->frag_id,
+		   (unsigned long) response->offset,
+		   (unsigned long) wpabuf_len(response->resp));
+	response->handler->status_cb(response->handler->ctx,
+				     response->resp, 0);
+	response->resp = NULL;
+	dl_list_del(&response->list);
+	gas_server_free_response(response);
+}
+
+
+static void gas_server_free_response(struct gas_server_response *response)
+{
+	if (!response)
+		return;
+	wpa_printf(MSG_DEBUG, "DPP: Free GAS response @%p", response);
+	eloop_cancel_timeout(gas_server_response_timeout, response, NULL);
+	wpabuf_free(response->resp);
+	os_free(response);
+}
+
+
+static void
+gas_server_send_resp(struct gas_server *gas, struct gas_server_handler *handler,
+		     const u8 *da, int freq, u8 dialog_token,
+		     struct wpabuf *query_resp)
+{
+	size_t max_len = (freq > 56160) ? 928 : 1400;
+	size_t hdr_len = 24 + 2 + 5 + 3 + handler->adv_proto_id_len + 2;
+	size_t resp_frag_len;
+	struct wpabuf *resp;
+	u16 comeback_delay;
+	struct gas_server_response *response;
+
+	if (!query_resp)
+		return;
+
+	response = os_zalloc(sizeof(*response));
+	if (!response) {
+		wpabuf_free(query_resp);
+		return;
+	}
+	wpa_printf(MSG_DEBUG, "DPP: Allocated GAS response @%p", response);
+	response->freq = freq;
+	response->handler = handler;
+	os_memcpy(response->dst, da, ETH_ALEN);
+	response->dialog_token = dialog_token;
+	if (hdr_len + wpabuf_len(query_resp) > max_len) {
+		/* Need to use comeback to initiate fragmentation */
+		comeback_delay = 1;
+		resp_frag_len = 0;
+	} else {
+		/* Full response fits into the initial response */
+		comeback_delay = 0;
+		resp_frag_len = wpabuf_len(query_resp);
+	}
+
+	resp = gas_build_initial_resp(dialog_token, WLAN_STATUS_SUCCESS,
+				      comeback_delay,
+				      handler->adv_proto_id_len +
+				      resp_frag_len);
+	if (!resp) {
+		wpabuf_free(query_resp);
+		gas_server_free_response(response);
+		return;
+	}
+
+	/* Advertisement Protocol element */
+	wpabuf_put_u8(resp, WLAN_EID_ADV_PROTO);
+	wpabuf_put_u8(resp, 1 + handler->adv_proto_id_len); /* Length */
+	wpabuf_put_u8(resp, 0x7f);
+	/* Advertisement Protocol ID */
+	wpabuf_put_data(resp, handler->adv_proto_id, handler->adv_proto_id_len);
+
+	/* Query Response Length */
+	wpabuf_put_le16(resp, resp_frag_len);
+	if (!comeback_delay)
+		wpabuf_put_buf(resp, query_resp);
+
+	if (comeback_delay) {
+		wpa_printf(MSG_DEBUG,
+			   "GAS: Need to fragment query response");
+	} else {
+		wpa_printf(MSG_DEBUG,
+			   "GAS: Full query response fits in the GAS Initial Response frame");
+	}
+	response->offset = resp_frag_len;
+	response->resp = query_resp;
+	dl_list_add(&gas->responses, &response->list);
+	gas->tx(gas->ctx, freq, da, resp, comeback_delay ? 2000 : 0);
+	wpabuf_free(resp);
+	eloop_register_timeout(GAS_QUERY_TIMEOUT, 0,
+			       gas_server_response_timeout, response, NULL);
+}
+
+
+static int
+gas_server_rx_initial_req(struct gas_server *gas, const u8 *da, const u8 *sa,
+			  const u8 *bssid, int freq, u8 dialog_token,
+			  const u8 *data, size_t len)
+{
+	const u8 *pos, *end, *adv_proto, *query_req;
+	u8 adv_proto_len;
+	u16 query_req_len;
+	struct gas_server_handler *handler;
+	struct wpabuf *resp;
+
+	wpa_hexdump(MSG_MSGDUMP, "GAS: Received GAS Initial Request frame",
+		    data, len);
+	pos = data;
+	end = data + len;
+
+	if (end - pos < 2 || pos[0] != WLAN_EID_ADV_PROTO) {
+		wpa_printf(MSG_DEBUG,
+			   "GAS: No Advertisement Protocol element found");
+		return -1;
+	}
+	pos++;
+	adv_proto_len = *pos++;
+	if (end - pos < adv_proto_len || adv_proto_len < 2) {
+		wpa_printf(MSG_DEBUG,
+			   "GAS: Truncated Advertisement Protocol element");
+		return -1;
+	}
+
+	adv_proto = pos;
+	pos += adv_proto_len;
+	wpa_hexdump(MSG_MSGDUMP, "GAS: Advertisement Protocol element",
+		    adv_proto, adv_proto_len);
+
+	if (end - pos < 2) {
+		wpa_printf(MSG_DEBUG, "GAS: No Query Request Length field");
+		return -1;
+	}
+	query_req_len = WPA_GET_LE16(pos);
+	pos += 2;
+	if (end - pos < query_req_len) {
+		wpa_printf(MSG_DEBUG, "GAS: Truncated Query Request field");
+		return -1;
+	}
+	query_req = pos;
+	pos += query_req_len;
+	wpa_hexdump(MSG_MSGDUMP, "GAS: Query Request",
+		    query_req, query_req_len);
+
+	if (pos < end) {
+		wpa_hexdump(MSG_MSGDUMP,
+			    "GAS: Ignored extra data after Query Request field",
+			    pos, end - pos);
+	}
+
+	dl_list_for_each(handler, &gas->handlers, struct gas_server_handler,
+			 list) {
+		if (adv_proto_len < 1 + handler->adv_proto_id_len ||
+		    os_memcmp(adv_proto + 1, handler->adv_proto_id,
+			      handler->adv_proto_id_len) != 0)
+			continue;
+
+		wpa_printf(MSG_DEBUG,
+			   "GAS: Calling handler for the requested Advertisement Protocol ID");
+		resp = handler->req_cb(handler->ctx, sa, query_req,
+				       query_req_len);
+		wpa_hexdump_buf(MSG_MSGDUMP, "GAS: Response from the handler",
+				resp);
+		gas_server_send_resp(gas, handler, sa, freq, dialog_token,
+				     resp);
+		return 0;
+	}
+
+	wpa_printf(MSG_DEBUG,
+		   "GAS: No registered handler for the requested Advertisement Protocol ID");
+	return -1;
+}
+
+
+static void
+gas_server_handle_rx_comeback_req(struct gas_server_response *response)
+{
+	struct gas_server_handler *handler = response->handler;
+	struct gas_server *gas = handler->gas;
+	size_t max_len = (response->freq > 56160) ? 928 : 1400;
+	size_t hdr_len = 24 + 2 + 6 + 3 + handler->adv_proto_id_len + 2;
+	size_t remaining, resp_frag_len;
+	struct wpabuf *resp;
+
+	remaining = wpabuf_len(response->resp) - response->offset;
+	if (hdr_len + remaining > max_len)
+		resp_frag_len = max_len - hdr_len;
+	else
+		resp_frag_len = remaining;
+	wpa_printf(MSG_DEBUG,
+		   "GAS: Sending out %u/%u remaining Query Response octets",
+		   (unsigned int) resp_frag_len, (unsigned int) remaining);
+
+	resp = gas_build_comeback_resp(response->dialog_token,
+				       WLAN_STATUS_SUCCESS,
+				       response->frag_id++,
+				       resp_frag_len < remaining, 0,
+				       handler->adv_proto_id_len +
+				       resp_frag_len);
+	if (!resp) {
+		dl_list_del(&response->list);
+		gas_server_free_response(response);
+		return;
+	}
+
+	/* Advertisement Protocol element */
+	wpabuf_put_u8(resp, WLAN_EID_ADV_PROTO);
+	wpabuf_put_u8(resp, 1 + handler->adv_proto_id_len); /* Length */
+	wpabuf_put_u8(resp, 0x7f);
+	/* Advertisement Protocol ID */
+	wpabuf_put_data(resp, handler->adv_proto_id, handler->adv_proto_id_len);
+
+	/* Query Response Length */
+	wpabuf_put_le16(resp, resp_frag_len);
+	wpabuf_put_data(resp, wpabuf_head_u8(response->resp) + response->offset,
+			resp_frag_len);
+
+	response->offset += resp_frag_len;
+
+	gas->tx(gas->ctx, response->freq, response->dst, resp,
+		remaining > resp_frag_len ? 2000 : 0);
+	wpabuf_free(resp);
+}
+
+
+static int
+gas_server_rx_comeback_req(struct gas_server *gas, const u8 *da, const u8 *sa,
+			   const u8 *bssid, int freq, u8 dialog_token)
+{
+	struct gas_server_response *response;
+
+	dl_list_for_each(response, &gas->responses, struct gas_server_response,
+			 list) {
+		if (response->dialog_token != dialog_token ||
+		    os_memcmp(sa, response->dst, ETH_ALEN) != 0)
+			continue;
+		gas_server_handle_rx_comeback_req(response);
+		return 0;
+	}
+
+	wpa_printf(MSG_DEBUG, "GAS: No pending GAS response for " MACSTR
+		   " (dialog token %u)", MAC2STR(sa), dialog_token);
+	return -1;
+}
+
+
+/**
+ * gas_query_rx - Indicate reception of a Public Action or Protected Dual frame
+ * @gas: GAS query data from gas_server_init()
+ * @da: Destination MAC address of the Action frame
+ * @sa: Source MAC address of the Action frame
+ * @bssid: BSSID of the Action frame
+ * @categ: Category of the Action frame
+ * @data: Payload of the Action frame
+ * @len: Length of @data
+ * @freq: Frequency (in MHz) on which the frame was received
+ * Returns: 0 if the Public Action frame was a GAS request frame or -1 if not
+ */
+int gas_server_rx(struct gas_server *gas, const u8 *da, const u8 *sa,
+		  const u8 *bssid, u8 categ, const u8 *data, size_t len,
+		  int freq)
+{
+	u8 action, dialog_token;
+	const u8 *pos, *end;
+
+	if (!gas || len < 2)
+		return -1;
+
+	if (categ == WLAN_ACTION_PROTECTED_DUAL)
+		return -1; /* Not supported for now */
+
+	pos = data;
+	end = data + len;
+	action = *pos++;
+	dialog_token = *pos++;
+
+	if (action != WLAN_PA_GAS_INITIAL_REQ &&
+	    action != WLAN_PA_GAS_COMEBACK_REQ)
+		return -1; /* Not a GAS request */
+
+	wpa_printf(MSG_DEBUG, "GAS: Received GAS %s Request frame DA=" MACSTR
+		   " SA=" MACSTR " BSSID=" MACSTR
+		   " freq=%d dialog_token=%u len=%u",
+		   action == WLAN_PA_GAS_INITIAL_REQ ? "Initial" : "Comeback",
+		   MAC2STR(da), MAC2STR(sa), MAC2STR(bssid), freq, dialog_token,
+		   (unsigned int) len);
+
+	if (action == WLAN_PA_GAS_INITIAL_REQ)
+		return gas_server_rx_initial_req(gas, da, sa, bssid,
+						 freq, dialog_token,
+						 pos, end - pos);
+	return gas_server_rx_comeback_req(gas, da, sa, bssid,
+					  freq, dialog_token);
+}
+
+
+static void gas_server_handle_tx_status(struct gas_server_response *response,
+					int ack)
+{
+	if (ack && response->offset < wpabuf_len(response->resp)) {
+		wpa_printf(MSG_DEBUG,
+			   "GAS: More fragments remaining - keep pending entry");
+		return;
+	}
+
+	if (!ack)
+		wpa_printf(MSG_DEBUG,
+			   "GAS: No ACK received - drop pending entry");
+	else
+		wpa_printf(MSG_DEBUG,
+			   "GAS: Last fragment of the response sent out - drop pending entry");
+
+	response->handler->status_cb(response->handler->ctx,
+				     response->resp, ack);
+	response->resp = NULL;
+	dl_list_del(&response->list);
+	gas_server_free_response(response);
+}
+
+
+void gas_server_tx_status(struct gas_server *gas, const u8 *dst, const u8 *data,
+			  size_t data_len, int ack)
+{
+	const u8 *pos;
+	u8 action, code, dialog_token;
+	struct gas_server_response *response;
+
+	if (data_len < 24 + 3)
+		return;
+	pos = data + 24;
+	action = *pos++;
+	code = *pos++;
+	dialog_token = *pos++;
+	if (action != WLAN_ACTION_PUBLIC ||
+	    (code != WLAN_PA_GAS_INITIAL_RESP &&
+	     code != WLAN_PA_GAS_COMEBACK_RESP))
+		return;
+	wpa_printf(MSG_DEBUG, "GAS: TX status dst=" MACSTR
+		   " ack=%d %s dialog_token=%u",
+		   MAC2STR(dst), ack,
+		   code == WLAN_PA_GAS_INITIAL_RESP ? "initial" : "comeback",
+		   dialog_token);
+	dl_list_for_each(response, &gas->responses, struct gas_server_response,
+			 list) {
+		if (response->dialog_token != dialog_token ||
+		    os_memcmp(dst, response->dst, ETH_ALEN) != 0)
+			continue;
+		gas_server_handle_tx_status(response, ack);
+		return;
+	}
+
+	wpa_printf(MSG_DEBUG, "GAS: No pending response matches TX status");
+}
+
+
+struct gas_server * gas_server_init(void *ctx,
+				    void (*tx)(void *ctx, int freq,
+					       const u8 *da,
+					       struct wpabuf *buf,
+					       unsigned int wait_time))
+{
+	struct gas_server *gas;
+
+	gas = os_zalloc(sizeof(*gas));
+	if (!gas)
+		return NULL;
+	gas->ctx = ctx;
+	gas->tx = tx;
+	dl_list_init(&gas->handlers);
+	dl_list_init(&gas->responses);
+	return gas;
+}
+
+
+void gas_server_deinit(struct gas_server *gas)
+{
+	struct gas_server_handler *handler, *tmp;
+	struct gas_server_response *response, *tmp_r;
+
+	if (!gas)
+		return;
+
+	dl_list_for_each_safe(handler, tmp, &gas->handlers,
+			      struct gas_server_handler, list) {
+		dl_list_del(&handler->list);
+		os_free(handler);
+	}
+
+	dl_list_for_each_safe(response, tmp_r, &gas->responses,
+			      struct gas_server_response, list) {
+		dl_list_del(&response->list);
+		gas_server_free_response(response);
+	}
+
+	os_free(gas);
+}
+
+
+int gas_server_register(struct gas_server *gas,
+			const u8 *adv_proto_id, u8 adv_proto_id_len,
+			struct wpabuf *
+			(*req_cb)(void *ctx, const u8 *sa,
+				  const u8 *query, size_t query_len),
+			void (*status_cb)(void *ctx, struct wpabuf *resp,
+					  int ok),
+			void *ctx)
+{
+	struct gas_server_handler *handler;
+
+	if (!gas || adv_proto_id_len > MAX_ADV_PROTO_ID_LEN)
+		return -1;
+	handler = os_zalloc(sizeof(*handler));
+	if (!handler)
+		return -1;
+
+	os_memcpy(handler->adv_proto_id, adv_proto_id, adv_proto_id_len);
+	handler->adv_proto_id_len = adv_proto_id_len;
+	handler->req_cb = req_cb;
+	handler->status_cb = status_cb;
+	handler->ctx = ctx;
+	handler->gas = gas;
+	dl_list_add(&gas->handlers, &handler->list);
+
+	return 0;
+}