/* * Wi-Fi Direct - P2P Invitation procedure * Copyright (c) 2010, Atheros Communications * * This software may be distributed under the terms of the BSD license. * See README for more details. */ #include "includes.h" #include "common.h" #include "common/ieee802_11_defs.h" #include "common/wpa_ctrl.h" #include "p2p_i.h" #include "p2p.h" static struct wpabuf * p2p_build_invitation_req(struct p2p_data *p2p, struct p2p_device *peer, const u8 *go_dev_addr, int dev_pw_id) { struct wpabuf *buf; u8 *len; const u8 *dev_addr; size_t extra = 0; #ifdef CONFIG_WIFI_DISPLAY struct wpabuf *wfd_ie = p2p->wfd_ie_invitation; if (wfd_ie && p2p->inv_role == P2P_INVITE_ROLE_ACTIVE_GO) { size_t i; for (i = 0; i < p2p->num_groups; i++) { struct p2p_group *g = p2p->groups[i]; struct wpabuf *ie; if (os_memcmp(p2p_group_get_interface_addr(g), p2p->inv_bssid, ETH_ALEN) != 0) continue; ie = p2p_group_get_wfd_ie(g); if (ie) { wfd_ie = ie; break; } } } if (wfd_ie) extra = wpabuf_len(wfd_ie); #endif /* CONFIG_WIFI_DISPLAY */ if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_INV_REQ]) extra += wpabuf_len(p2p->vendor_elem[VENDOR_ELEM_P2P_INV_REQ]); buf = wpabuf_alloc(1000 + extra); if (buf == NULL) return NULL; peer->dialog_token++; if (peer->dialog_token == 0) peer->dialog_token = 1; p2p_buf_add_public_action_hdr(buf, P2P_INVITATION_REQ, peer->dialog_token); len = p2p_buf_add_ie_hdr(buf); if (p2p->inv_role == P2P_INVITE_ROLE_ACTIVE_GO || !p2p->inv_persistent) p2p_buf_add_config_timeout(buf, 0, 0); else p2p_buf_add_config_timeout(buf, p2p->go_timeout, p2p->client_timeout); p2p_buf_add_invitation_flags(buf, p2p->inv_persistent ? P2P_INVITATION_FLAGS_TYPE : 0); if (p2p->inv_role != P2P_INVITE_ROLE_CLIENT || !(peer->flags & P2P_DEV_NO_PREF_CHAN)) p2p_buf_add_operating_channel(buf, p2p->cfg->country, p2p->op_reg_class, p2p->op_channel); if (p2p->inv_bssid_set) p2p_buf_add_group_bssid(buf, p2p->inv_bssid); p2p_buf_add_channel_list(buf, p2p->cfg->country, &p2p->channels); if (go_dev_addr) dev_addr = go_dev_addr; else if (p2p->inv_role == P2P_INVITE_ROLE_CLIENT) dev_addr = peer->info.p2p_device_addr; else dev_addr = p2p->cfg->dev_addr; p2p_buf_add_group_id(buf, dev_addr, p2p->inv_ssid, p2p->inv_ssid_len); p2p_buf_add_device_info(buf, p2p, peer); p2p_buf_update_ie_hdr(buf, len); #ifdef CONFIG_WIFI_DISPLAY if (wfd_ie) wpabuf_put_buf(buf, wfd_ie); #endif /* CONFIG_WIFI_DISPLAY */ if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_INV_REQ]) wpabuf_put_buf(buf, p2p->vendor_elem[VENDOR_ELEM_P2P_INV_REQ]); if (dev_pw_id >= 0) { /* WSC IE in Invitation Request for NFC static handover */ p2p_build_wps_ie(p2p, buf, dev_pw_id, 0); } return buf; } static struct wpabuf * p2p_build_invitation_resp(struct p2p_data *p2p, struct p2p_device *peer, u8 dialog_token, u8 status, const u8 *group_bssid, u8 reg_class, u8 channel, struct p2p_channels *channels) { struct wpabuf *buf; u8 *len; size_t extra = 0; #ifdef CONFIG_WIFI_DISPLAY struct wpabuf *wfd_ie = p2p->wfd_ie_invitation; if (wfd_ie && group_bssid) { size_t i; for (i = 0; i < p2p->num_groups; i++) { struct p2p_group *g = p2p->groups[i]; struct wpabuf *ie; if (os_memcmp(p2p_group_get_interface_addr(g), group_bssid, ETH_ALEN) != 0) continue; ie = p2p_group_get_wfd_ie(g); if (ie) { wfd_ie = ie; break; } } } if (wfd_ie) extra = wpabuf_len(wfd_ie); #endif /* CONFIG_WIFI_DISPLAY */ buf = wpabuf_alloc(1000 + extra); if (buf == NULL) return NULL; p2p_buf_add_public_action_hdr(buf, P2P_INVITATION_RESP, dialog_token); len = p2p_buf_add_ie_hdr(buf); p2p_buf_add_status(buf, status); p2p_buf_add_config_timeout(buf, 0, 0); /* FIX */ if (reg_class && channel) p2p_buf_add_operating_channel(buf, p2p->cfg->country, reg_class, channel); if (group_bssid) p2p_buf_add_group_bssid(buf, group_bssid); if (channels) p2p_buf_add_channel_list(buf, p2p->cfg->country, channels); p2p_buf_update_ie_hdr(buf, len); #ifdef CONFIG_WIFI_DISPLAY if (wfd_ie) wpabuf_put_buf(buf, wfd_ie); #endif /* CONFIG_WIFI_DISPLAY */ return buf; } void p2p_process_invitation_req(struct p2p_data *p2p, const u8 *sa, const u8 *data, size_t len, int rx_freq) { struct p2p_device *dev; struct p2p_message msg; struct wpabuf *resp = NULL; u8 status = P2P_SC_FAIL_INFO_CURRENTLY_UNAVAILABLE; int freq; int go = 0; u8 group_bssid[ETH_ALEN], *bssid; int op_freq = 0; u8 reg_class = 0, channel = 0; struct p2p_channels all_channels, intersection, *channels = NULL; int persistent; os_memset(group_bssid, 0, sizeof(group_bssid)); p2p_dbg(p2p, "Received Invitation Request from " MACSTR " (freq=%d)", MAC2STR(sa), rx_freq); if (p2p_parse(data, len, &msg)) return; dev = p2p_get_device(p2p, sa); if (dev == NULL || (dev->flags & P2P_DEV_PROBE_REQ_ONLY)) { p2p_dbg(p2p, "Invitation Request from unknown peer " MACSTR, MAC2STR(sa)); if (p2p_add_device(p2p, sa, rx_freq, NULL, 0, data + 1, len - 1, 0)) { p2p_dbg(p2p, "Invitation Request add device failed " MACSTR, MAC2STR(sa)); status = P2P_SC_FAIL_INFO_CURRENTLY_UNAVAILABLE; goto fail; } dev = p2p_get_device(p2p, sa); if (dev == NULL) { p2p_dbg(p2p, "Reject Invitation Request from unknown peer " MACSTR, MAC2STR(sa)); status = P2P_SC_FAIL_INFO_CURRENTLY_UNAVAILABLE; goto fail; } } if (!msg.group_id || !msg.channel_list) { p2p_dbg(p2p, "Mandatory attribute missing in Invitation Request from " MACSTR, MAC2STR(sa)); status = P2P_SC_FAIL_INVALID_PARAMS; goto fail; } if (msg.invitation_flags) persistent = *msg.invitation_flags & P2P_INVITATION_FLAGS_TYPE; else { /* Invitation Flags is a mandatory attribute starting from P2P * spec 1.06. As a backwards compatibility mechanism, assume * the request was for a persistent group if the attribute is * missing. */ p2p_dbg(p2p, "Mandatory Invitation Flags attribute missing from Invitation Request"); persistent = 1; } p2p_channels_union(&p2p->cfg->channels, &p2p->cfg->cli_channels, &all_channels); if (p2p_peer_channels_check(p2p, &all_channels, dev, msg.channel_list, msg.channel_list_len) < 0) { p2p_dbg(p2p, "No common channels found"); status = P2P_SC_FAIL_NO_COMMON_CHANNELS; goto fail; } p2p_channels_dump(p2p, "own channels", &p2p->cfg->channels); p2p_channels_dump(p2p, "own client channels", &all_channels); p2p_channels_dump(p2p, "peer channels", &dev->channels); p2p_channels_intersect(&all_channels, &dev->channels, &intersection); p2p_channels_dump(p2p, "intersection", &intersection); if (p2p->cfg->invitation_process) { status = p2p->cfg->invitation_process( p2p->cfg->cb_ctx, sa, msg.group_bssid, msg.group_id, msg.group_id + ETH_ALEN, msg.group_id_len - ETH_ALEN, &go, group_bssid, &op_freq, persistent, &intersection, msg.dev_password_id_present ? msg.dev_password_id : -1); } if (go) { p2p_channels_intersect(&p2p->cfg->channels, &dev->channels, &intersection); p2p_channels_dump(p2p, "intersection(GO)", &intersection); if (intersection.reg_classes == 0) { p2p_dbg(p2p, "No common channels found (GO)"); status = P2P_SC_FAIL_NO_COMMON_CHANNELS; goto fail; } } if (op_freq) { p2p_dbg(p2p, "Invitation processing forced frequency %d MHz", op_freq); if (p2p_freq_to_channel(op_freq, ®_class, &channel) < 0) { p2p_dbg(p2p, "Unknown forced freq %d MHz from invitation_process()", op_freq); status = P2P_SC_FAIL_NO_COMMON_CHANNELS; goto fail; } if (!p2p_channels_includes(&intersection, reg_class, channel)) { p2p_dbg(p2p, "forced freq %d MHz not in the supported channels interaction", op_freq); status = P2P_SC_FAIL_NO_COMMON_CHANNELS; goto fail; } if (status == P2P_SC_SUCCESS) channels = &intersection; } else { p2p_dbg(p2p, "No forced channel from invitation processing - figure out best one to use"); /* Default to own configuration as a starting point */ p2p->op_reg_class = p2p->cfg->op_reg_class; p2p->op_channel = p2p->cfg->op_channel; p2p_dbg(p2p, "Own default op_class %d channel %d", p2p->op_reg_class, p2p->op_channel); /* Use peer preference if specified and compatible */ if (msg.operating_channel) { int req_freq; req_freq = p2p_channel_to_freq( msg.operating_channel[3], msg.operating_channel[4]); p2p_dbg(p2p, "Peer operating channel preference: %d MHz", req_freq); if (req_freq > 0 && p2p_channels_includes(&intersection, msg.operating_channel[3], msg.operating_channel[4])) { p2p->op_reg_class = msg.operating_channel[3]; p2p->op_channel = msg.operating_channel[4]; p2p_dbg(p2p, "Use peer preference op_class %d channel %d", p2p->op_reg_class, p2p->op_channel); } else { p2p_dbg(p2p, "Cannot use peer channel preference"); } } /* Reselect the channel only for the case of the GO */ if (go && !p2p_channels_includes(&intersection, p2p->op_reg_class, p2p->op_channel)) { p2p_dbg(p2p, "Initially selected channel (op_class %d channel %d) not in channel intersection - try to reselect", p2p->op_reg_class, p2p->op_channel); p2p_reselect_channel(p2p, &intersection); p2p_dbg(p2p, "Re-selection result: op_class %d channel %d", p2p->op_reg_class, p2p->op_channel); if (!p2p_channels_includes(&intersection, p2p->op_reg_class, p2p->op_channel)) { p2p_dbg(p2p, "Peer does not support selected operating channel (reg_class=%u channel=%u)", p2p->op_reg_class, p2p->op_channel); status = P2P_SC_FAIL_NO_COMMON_CHANNELS; goto fail; } } else if (go && !(dev->flags & P2P_DEV_FORCE_FREQ) && !p2p->cfg->cfg_op_channel) { p2p_dbg(p2p, "Try to reselect channel selection with peer information received; previously selected op_class %u channel %u", p2p->op_reg_class, p2p->op_channel); p2p_reselect_channel(p2p, &intersection); } op_freq = p2p_channel_to_freq(p2p->op_reg_class, p2p->op_channel); if (op_freq < 0) { p2p_dbg(p2p, "Unknown operational channel (country=%c%c reg_class=%u channel=%u)", p2p->cfg->country[0], p2p->cfg->country[1], p2p->op_reg_class, p2p->op_channel); status = P2P_SC_FAIL_NO_COMMON_CHANNELS; goto fail; } p2p_dbg(p2p, "Selected operating channel - %d MHz", op_freq); if (status == P2P_SC_SUCCESS) { reg_class = p2p->op_reg_class; channel = p2p->op_channel; channels = &intersection; } } fail: if (go && status == P2P_SC_SUCCESS && !is_zero_ether_addr(group_bssid)) bssid = group_bssid; else bssid = NULL; resp = p2p_build_invitation_resp(p2p, dev, msg.dialog_token, status, bssid, reg_class, channel, channels); if (resp == NULL) goto out; if (rx_freq > 0) freq = rx_freq; else freq = p2p_channel_to_freq(p2p->cfg->reg_class, p2p->cfg->channel); if (freq < 0) { p2p_dbg(p2p, "Unknown regulatory class/channel"); goto out; } /* * Store copy of invitation data to be used when processing TX status * callback for the Acton frame. */ os_memcpy(p2p->inv_sa, sa, ETH_ALEN); if (msg.group_bssid) { os_memcpy(p2p->inv_group_bssid, msg.group_bssid, ETH_ALEN); p2p->inv_group_bssid_ptr = p2p->inv_group_bssid; } else p2p->inv_group_bssid_ptr = NULL; if (msg.group_id) { if (msg.group_id_len - ETH_ALEN <= SSID_MAX_LEN) { os_memcpy(p2p->inv_ssid, msg.group_id + ETH_ALEN, msg.group_id_len - ETH_ALEN); p2p->inv_ssid_len = msg.group_id_len - ETH_ALEN; } os_memcpy(p2p->inv_go_dev_addr, msg.group_id, ETH_ALEN); } else { p2p->inv_ssid_len = 0; os_memset(p2p->inv_go_dev_addr, 0, ETH_ALEN); } p2p->inv_status = status; p2p->inv_op_freq = op_freq; p2p->pending_action_state = P2P_PENDING_INVITATION_RESPONSE; if (p2p_send_action(p2p, freq, sa, p2p->cfg->dev_addr, p2p->cfg->dev_addr, wpabuf_head(resp), wpabuf_len(resp), 200) < 0) { p2p_dbg(p2p, "Failed to send Action frame"); } out: wpabuf_free(resp); p2p_parse_free(&msg); } void p2p_process_invitation_resp(struct p2p_data *p2p, const u8 *sa, const u8 *data, size_t len) { struct p2p_device *dev; struct p2p_message msg; struct p2p_channels intersection, *channels = NULL; p2p_dbg(p2p, "Received Invitation Response from " MACSTR, MAC2STR(sa)); dev = p2p_get_device(p2p, sa); if (dev == NULL) { p2p_dbg(p2p, "Ignore Invitation Response from unknown peer " MACSTR, MAC2STR(sa)); p2p->cfg->send_action_done(p2p->cfg->cb_ctx); return; } if (dev != p2p->invite_peer) { p2p_dbg(p2p, "Ignore unexpected Invitation Response from peer " MACSTR, MAC2STR(sa)); p2p->cfg->send_action_done(p2p->cfg->cb_ctx); return; } if (p2p_parse(data, len, &msg)) { p2p->cfg->send_action_done(p2p->cfg->cb_ctx); return; } if (!msg.status) { p2p_dbg(p2p, "Mandatory Status attribute missing in Invitation Response from " MACSTR, MAC2STR(sa)); p2p_parse_free(&msg); p2p->cfg->send_action_done(p2p->cfg->cb_ctx); return; } /* * We should not really receive a replayed response twice since * duplicate frames are supposed to be dropped. However, not all drivers * do that for pre-association frames. We did not use to verify dialog * token matches for invitation response frames, but that check can be * safely used to drop a replayed response to the previous Invitation * Request in case the suggested operating channel was changed. This * allows a duplicated reject frame to be dropped with the assumption * that the real response follows after it. */ if (*msg.status == P2P_SC_FAIL_NO_COMMON_CHANNELS && p2p->retry_invite_req_sent && msg.dialog_token != dev->dialog_token) { p2p_dbg(p2p, "Unexpected Dialog Token %u (expected %u)", msg.dialog_token, dev->dialog_token); p2p_parse_free(&msg); return; } if (*msg.status == P2P_SC_FAIL_NO_COMMON_CHANNELS && p2p->retry_invite_req && p2p_channel_random_social(&p2p->cfg->channels, &p2p->op_reg_class, &p2p->op_channel) == 0) { p2p->retry_invite_req = 0; p2p->cfg->send_action_done(p2p->cfg->cb_ctx); p2p->cfg->stop_listen(p2p->cfg->cb_ctx); p2p_set_state(p2p, P2P_INVITE); p2p_dbg(p2p, "Resend Invitation Request setting op_class %u channel %u as operating channel", p2p->op_reg_class, p2p->op_channel); p2p->retry_invite_req_sent = 1; p2p_invite_send(p2p, p2p->invite_peer, p2p->invite_go_dev_addr, p2p->invite_dev_pw_id); p2p_parse_free(&msg); return; } p2p->cfg->send_action_done(p2p->cfg->cb_ctx); p2p->retry_invite_req = 0; if (!msg.channel_list && *msg.status == P2P_SC_SUCCESS) { p2p_dbg(p2p, "Mandatory Channel List attribute missing in Invitation Response from " MACSTR, MAC2STR(sa)); #ifdef CONFIG_P2P_STRICT p2p_parse_free(&msg); return; #endif /* CONFIG_P2P_STRICT */ /* Try to survive without peer channel list */ channels = &p2p->channels; } else if (!msg.channel_list) { /* Non-success cases are not required to include Channel List */ channels = &p2p->channels; } else if (p2p_peer_channels_check(p2p, &p2p->channels, dev, msg.channel_list, msg.channel_list_len) < 0) { p2p_dbg(p2p, "No common channels found"); p2p_parse_free(&msg); return; } else { p2p_channels_intersect(&p2p->channels, &dev->channels, &intersection); channels = &intersection; } if (p2p->cfg->invitation_result) { int peer_oper_freq = 0; int freq = p2p_channel_to_freq(p2p->op_reg_class, p2p->op_channel); if (freq < 0) freq = 0; if (msg.operating_channel) { peer_oper_freq = p2p_channel_to_freq( msg.operating_channel[3], msg.operating_channel[4]); if (peer_oper_freq < 0) peer_oper_freq = 0; } p2p->cfg->invitation_result(p2p->cfg->cb_ctx, *msg.status, msg.group_bssid, channels, sa, freq, peer_oper_freq); } p2p_parse_free(&msg); p2p_clear_timeout(p2p); p2p_set_state(p2p, P2P_IDLE); p2p->invite_peer = NULL; } int p2p_invite_send(struct p2p_data *p2p, struct p2p_device *dev, const u8 *go_dev_addr, int dev_pw_id) { struct wpabuf *req; int freq; freq = dev->listen_freq > 0 ? dev->listen_freq : dev->oper_freq; if (freq <= 0) freq = dev->oob_go_neg_freq; if (freq <= 0) { p2p_dbg(p2p, "No Listen/Operating frequency known for the peer " MACSTR " to send Invitation Request", MAC2STR(dev->info.p2p_device_addr)); return -1; } req = p2p_build_invitation_req(p2p, dev, go_dev_addr, dev_pw_id); if (req == NULL) return -1; if (p2p->state != P2P_IDLE) p2p_stop_listen_for_freq(p2p, freq); p2p_dbg(p2p, "Sending Invitation Request"); p2p_set_state(p2p, P2P_INVITE); p2p->pending_action_state = P2P_PENDING_INVITATION_REQUEST; p2p->invite_peer = dev; dev->invitation_reqs++; if (p2p_send_action(p2p, freq, dev->info.p2p_device_addr, p2p->cfg->dev_addr, dev->info.p2p_device_addr, wpabuf_head(req), wpabuf_len(req), 500) < 0) { p2p_dbg(p2p, "Failed to send Action frame"); /* Use P2P find to recover and retry */ p2p_set_timeout(p2p, 0, 0); } else { dev->flags |= P2P_DEV_WAIT_INV_REQ_ACK; } wpabuf_free(req); return 0; } void p2p_invitation_req_cb(struct p2p_data *p2p, int success) { p2p_dbg(p2p, "Invitation Request TX callback: success=%d", success); if (p2p->invite_peer == NULL) { p2p_dbg(p2p, "No pending Invite"); return; } if (success) p2p->invite_peer->flags &= ~P2P_DEV_WAIT_INV_REQ_ACK; /* * Use P2P find, if needed, to find the other device from its listen * channel. */ p2p_set_state(p2p, P2P_INVITE); p2p_set_timeout(p2p, 0, success ? 500000 : 100000); } void p2p_invitation_resp_cb(struct p2p_data *p2p, int success) { p2p_dbg(p2p, "Invitation Response TX callback: success=%d", success); p2p->cfg->send_action_done(p2p->cfg->cb_ctx); if (!success) p2p_dbg(p2p, "Assume Invitation Response was actually received by the peer even though Ack was not reported"); if (p2p->cfg->invitation_received) { p2p->cfg->invitation_received(p2p->cfg->cb_ctx, p2p->inv_sa, p2p->inv_group_bssid_ptr, p2p->inv_ssid, p2p->inv_ssid_len, p2p->inv_go_dev_addr, p2p->inv_status, p2p->inv_op_freq); } } int p2p_invite(struct p2p_data *p2p, const u8 *peer, enum p2p_invite_role role, const u8 *bssid, const u8 *ssid, size_t ssid_len, unsigned int force_freq, const u8 *go_dev_addr, int persistent_group, unsigned int pref_freq, int dev_pw_id) { struct p2p_device *dev; p2p_dbg(p2p, "Request to invite peer " MACSTR " role=%d persistent=%d " "force_freq=%u", MAC2STR(peer), role, persistent_group, force_freq); if (bssid) p2p_dbg(p2p, "Invitation for BSSID " MACSTR, MAC2STR(bssid)); if (go_dev_addr) { p2p_dbg(p2p, "Invitation for GO Device Address " MACSTR, MAC2STR(go_dev_addr)); os_memcpy(p2p->invite_go_dev_addr_buf, go_dev_addr, ETH_ALEN); p2p->invite_go_dev_addr = p2p->invite_go_dev_addr_buf; } else p2p->invite_go_dev_addr = NULL; wpa_hexdump_ascii(MSG_DEBUG, "Invitation for SSID", ssid, ssid_len); if (dev_pw_id >= 0) { p2p_dbg(p2p, "Invitation to use Device Password ID %d", dev_pw_id); } p2p->invite_dev_pw_id = dev_pw_id; p2p->retry_invite_req = role == P2P_INVITE_ROLE_GO && persistent_group && !force_freq; p2p->retry_invite_req_sent = 0; dev = p2p_get_device(p2p, peer); if (dev == NULL || (dev->listen_freq <= 0 && dev->oper_freq <= 0 && dev->oob_go_neg_freq <= 0)) { p2p_dbg(p2p, "Cannot invite unknown P2P Device " MACSTR, MAC2STR(peer)); return -1; } if (p2p_prepare_channel(p2p, dev, force_freq, pref_freq, role != P2P_INVITE_ROLE_CLIENT) < 0) return -1; if (persistent_group && role == P2P_INVITE_ROLE_CLIENT && !force_freq && !pref_freq) dev->flags |= P2P_DEV_NO_PREF_CHAN; else dev->flags &= ~P2P_DEV_NO_PREF_CHAN; if (dev->flags & P2P_DEV_GROUP_CLIENT_ONLY) { if (!(dev->info.dev_capab & P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY)) { p2p_dbg(p2p, "Cannot invite a P2P Device " MACSTR " that is in a group and is not discoverable", MAC2STR(peer)); } /* TODO: use device discoverability request through GO */ } dev->invitation_reqs = 0; if (p2p->state != P2P_IDLE) p2p_stop_find(p2p); p2p->inv_role = role; p2p->inv_bssid_set = bssid != NULL; if (bssid) os_memcpy(p2p->inv_bssid, bssid, ETH_ALEN); os_memcpy(p2p->inv_ssid, ssid, ssid_len); p2p->inv_ssid_len = ssid_len; p2p->inv_persistent = persistent_group; return p2p_invite_send(p2p, dev, go_dev_addr, dev_pw_id); }