--- /dev/null
+/*
+ * Generic advertisement service (GAS) (IEEE 802.11u)
+ * Copyright (c) 2009, Atheros Communications
+ * Copyright (c) 2011-2012, Qualcomm Atheros
+ *
+ * This software may be distributed under the terms of the BSD license.
+ * See README for more details.
+ */
+
+#include "includes.h"
+
+#include "common.h"
+#include "ieee802_11_defs.h"
+#include "gas.h"
+
+
+static struct wpabuf *
+gas_build_req(u8 action, u8 dialog_token, size_t size)
+{
+ struct wpabuf *buf;
+
+ buf = wpabuf_alloc(100 + size);
+ if (buf == NULL)
+ return NULL;
+
+ wpabuf_put_u8(buf, WLAN_ACTION_PUBLIC);
+ wpabuf_put_u8(buf, action);
+ wpabuf_put_u8(buf, dialog_token);
+
+ return buf;
+}
+
+
+struct wpabuf * gas_build_initial_req(u8 dialog_token, size_t size)
+{
+ return gas_build_req(WLAN_PA_GAS_INITIAL_REQ, dialog_token,
+ size);
+}
+
+
+struct wpabuf * gas_build_comeback_req(u8 dialog_token)
+{
+ return gas_build_req(WLAN_PA_GAS_COMEBACK_REQ, dialog_token, 0);
+}
+
+
+static struct wpabuf *
+gas_build_resp(u8 action, u8 dialog_token, u16 status_code, u8 frag_id,
+ u8 more, u16 comeback_delay, size_t size)
+{
+ struct wpabuf *buf;
+
+ buf = wpabuf_alloc(100 + size);
+ if (buf == NULL)
+ return NULL;
+
+ wpabuf_put_u8(buf, WLAN_ACTION_PUBLIC);
+ wpabuf_put_u8(buf, action);
+ wpabuf_put_u8(buf, dialog_token);
+ wpabuf_put_le16(buf, status_code);
+ if (action == WLAN_PA_GAS_COMEBACK_RESP)
+ wpabuf_put_u8(buf, frag_id | (more ? 0x80 : 0));
+ wpabuf_put_le16(buf, comeback_delay);
+
+ return buf;
+}
+
+
+struct wpabuf *
+gas_build_initial_resp(u8 dialog_token, u16 status_code, u16 comeback_delay,
+ size_t size)
+{
+ return gas_build_resp(WLAN_PA_GAS_INITIAL_RESP, dialog_token,
+ status_code, 0, 0, comeback_delay, size);
+}
+
+
+static struct wpabuf *
+gas_build_comeback_resp(u8 dialog_token, u16 status_code, u8 frag_id, u8 more,
+ u16 comeback_delay, size_t size)
+{
+ return gas_build_resp(WLAN_PA_GAS_COMEBACK_RESP, dialog_token,
+ status_code, frag_id, more, comeback_delay,
+ size);
+}
+
+
+/**
+ * gas_add_adv_proto_anqp - Add an Advertisement Protocol element
+ * @buf: Buffer to which the element is added
+ * @query_resp_len_limit: Query Response Length Limit in units of 256 octets
+ * @pame_bi: Pre-Association Message Exchange BSSID Independent (0/1)
+ *
+ *
+ * @query_resp_len_limit is 0 for request and 1-0x7f for response. 0x7f means
+ * that the maximum limit is determined by the maximum allowable number of
+ * fragments in the GAS Query Response Fragment ID.
+ */
+static void gas_add_adv_proto_anqp(struct wpabuf *buf, u8 query_resp_len_limit,
+ u8 pame_bi)
+{
+ /* Advertisement Protocol IE */
+ wpabuf_put_u8(buf, WLAN_EID_ADV_PROTO);
+ wpabuf_put_u8(buf, 2); /* Length */
+ wpabuf_put_u8(buf, (query_resp_len_limit & 0x7f) |
+ (pame_bi ? 0x80 : 0));
+ /* Advertisement Protocol */
+ wpabuf_put_u8(buf, ACCESS_NETWORK_QUERY_PROTOCOL);
+}
+
+
+struct wpabuf * gas_anqp_build_initial_req(u8 dialog_token, size_t size)
+{
+ struct wpabuf *buf;
+
+ buf = gas_build_initial_req(dialog_token, 4 + size);
+ if (buf == NULL)
+ return NULL;
+
+ gas_add_adv_proto_anqp(buf, 0, 0);
+
+ wpabuf_put(buf, 2); /* Query Request Length to be filled */
+
+ return buf;
+}
+
+
+struct wpabuf * gas_anqp_build_initial_resp(u8 dialog_token, u16 status_code,
+ u16 comeback_delay, size_t size)
+{
+ struct wpabuf *buf;
+
+ buf = gas_build_initial_resp(dialog_token, status_code, comeback_delay,
+ 4 + size);
+ if (buf == NULL)
+ return NULL;
+
+ gas_add_adv_proto_anqp(buf, 0x7f, 0);
+
+ wpabuf_put(buf, 2); /* Query Response Length to be filled */
+
+ return buf;
+}
+
+
+struct wpabuf * gas_anqp_build_initial_resp_buf(u8 dialog_token,
+ u16 status_code,
+ u16 comeback_delay,
+ struct wpabuf *payload)
+{
+ struct wpabuf *buf;
+
+ buf = gas_anqp_build_initial_resp(dialog_token, status_code,
+ comeback_delay,
+ payload ? wpabuf_len(payload) : 0);
+ if (buf == NULL)
+ return NULL;
+
+ if (payload)
+ wpabuf_put_buf(buf, payload);
+
+ gas_anqp_set_len(buf);
+
+ return buf;
+}
+
+
+struct wpabuf * gas_anqp_build_comeback_resp(u8 dialog_token, u16 status_code,
+ u8 frag_id, u8 more,
+ u16 comeback_delay, size_t size)
+{
+ struct wpabuf *buf;
+
+ buf = gas_build_comeback_resp(dialog_token, status_code,
+ frag_id, more, comeback_delay, 4 + size);
+ if (buf == NULL)
+ return NULL;
+
+ gas_add_adv_proto_anqp(buf, 0x7f, 0);
+
+ wpabuf_put(buf, 2); /* Query Response Length to be filled */
+
+ return buf;
+}
+
+
+struct wpabuf * gas_anqp_build_comeback_resp_buf(u8 dialog_token,
+ u16 status_code,
+ u8 frag_id, u8 more,
+ u16 comeback_delay,
+ struct wpabuf *payload)
+{
+ struct wpabuf *buf;
+
+ buf = gas_anqp_build_comeback_resp(dialog_token, status_code, frag_id,
+ more, comeback_delay,
+ payload ? wpabuf_len(payload) : 0);
+ if (buf == NULL)
+ return NULL;
+
+ if (payload)
+ wpabuf_put_buf(buf, payload);
+
+ gas_anqp_set_len(buf);
+
+ return buf;
+}
+
+
+/**
+ * gas_anqp_set_len - Set Query Request/Response Length
+ * @buf: GAS message
+ *
+ * This function is used to update the Query Request/Response Length field once
+ * the payload has been filled.
+ */
+void gas_anqp_set_len(struct wpabuf *buf)
+{
+ u8 action;
+ size_t offset;
+ u8 *len;
+
+ if (buf == NULL || wpabuf_len(buf) < 2)
+ return;
+
+ action = *(wpabuf_head_u8(buf) + 1);
+ switch (action) {
+ case WLAN_PA_GAS_INITIAL_REQ:
+ offset = 3 + 4;
+ break;
+ case WLAN_PA_GAS_INITIAL_RESP:
+ offset = 7 + 4;
+ break;
+ case WLAN_PA_GAS_COMEBACK_RESP:
+ offset = 8 + 4;
+ break;
+ default:
+ return;
+ }
+
+ if (wpabuf_len(buf) < offset + 2)
+ return;
+
+ len = wpabuf_mhead_u8(buf) + offset;
+ WPA_PUT_LE16(len, (u8 *) wpabuf_put(buf, 0) - len - 2);
+}
+
+
+/**
+ * gas_anqp_add_element - Add ANQP element header
+ * @buf: GAS message
+ * @info_id: ANQP Info ID
+ * Returns: Pointer to the Length field for gas_anqp_set_element_len()
+ */
+u8 * gas_anqp_add_element(struct wpabuf *buf, u16 info_id)
+{
+ wpabuf_put_le16(buf, info_id);
+ return wpabuf_put(buf, 2); /* Length to be filled */
+}
+
+
+/**
+ * gas_anqp_set_element_len - Update ANQP element Length field
+ * @buf: GAS message
+ * @len_pos: Length field position from gas_anqp_add_element()
+ *
+ * This function is called after the ANQP element payload has been added to the
+ * buffer.
+ */
+void gas_anqp_set_element_len(struct wpabuf *buf, u8 *len_pos)
+{
+ WPA_PUT_LE16(len_pos, (u8 *) wpabuf_put(buf, 0) - len_pos - 2);
+}
projects / mech_eap.git / blobdiff