/* * WiMedia Logical Link Control Protocol (WLP) * * Copyright (C) 2007 Intel Corporation * Reinette Chatre <reinette.chatre@intel.com> * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License version * 2 as published by the Free Software Foundation. * * 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. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA * 02110-1301, USA. * * * Implementation of the WLP association protocol. * * FIXME: Docs * * A UWB network interface will configure a WSS through wlp_wss_setup() after * the interface has been assigned a MAC address, typically after * "ifconfig" has been called. When the interface goes down it should call * wlp_wss_remove(). * * When the WSS is ready for use the user interacts via sysfs to create, * discover, and activate WSS. * * wlp_wss_enroll_activate() * * wlp_wss_create_activate() * wlp_wss_set_wssid_hash() * wlp_wss_comp_wssid_hash() * wlp_wss_sel_bcast_addr() * wlp_wss_sysfs_add() * * Called when no more references to WSS exist: * wlp_wss_release() * wlp_wss_reset() */ #include <linux/etherdevice.h> /* for is_valid_ether_addr */ #include <linux/skbuff.h> #include <linux/wlp.h> #include "wlp-internal.h" size_t wlp_wss_key_print(char *buf, size_t bufsize, u8 *key) { size_t result; result = scnprintf(buf, bufsize, "%02x %02x %02x %02x %02x %02x " "%02x %02x %02x %02x %02x %02x " "%02x %02x %02x %02x", key[0], key[1], key[2], key[3], key[4], key[5], key[6], key[7], key[8], key[9], key[10], key[11], key[12], key[13], key[14], key[15]); return result; } /** * Compute WSSID hash * WLP Draft 0.99 [7.2.1] * * The WSSID hash for a WSSID is the result of an octet-wise exclusive-OR * of all octets in the WSSID. */ static u8 wlp_wss_comp_wssid_hash(struct wlp_uuid *wssid) { return wssid->data[0] ^ wssid->data[1] ^ wssid->data[2] ^ wssid->data[3] ^ wssid->data[4] ^ wssid->data[5] ^ wssid->data[6] ^ wssid->data[7] ^ wssid->data[8] ^ wssid->data[9] ^ wssid->data[10] ^ wssid->data[11] ^ wssid->data[12] ^ wssid->data[13] ^ wssid->data[14] ^ wssid->data[15]; } /** * Select a multicast EUI-48 for the WSS broadcast address. * WLP Draft 0.99 [7.2.1] * * Selected based on the WiMedia Alliance OUI, 00-13-88, within the WLP * range, [01-13-88-00-01-00, 01-13-88-00-01-FF] inclusive. * * This address is currently hardcoded. * FIXME? */ static struct uwb_mac_addr wlp_wss_sel_bcast_addr(struct wlp_wss *wss) { struct uwb_mac_addr bcast = { .data = { 0x01, 0x13, 0x88, 0x00, 0x01, 0x00 } }; return bcast; } /** * Clear the contents of the WSS structure - all except kobj, mutex, virtual * * We do not want to reinitialize - the internal kobj should not change as * it still points to the parent received during setup. The mutex should * remain also. We thus just reset values individually. * The virutal address assigned to WSS will remain the same for the * lifetime of the WSS. We only reset the fields that can change during its * lifetime. */ void wlp_wss_reset(struct wlp_wss *wss) { memset(&wss->wssid, 0, sizeof(wss->wssid)); wss->hash = 0; memset(&wss->name[0], 0, sizeof(wss->name)); memset(&wss->bcast, 0, sizeof(wss->bcast)); wss->secure_status = WLP_WSS_UNSECURE; memset(&wss->master_key[0], 0, sizeof(wss->master_key)); wss->tag = 0; wss->state = WLP_WSS_STATE_NONE; } /** * Create sysfs infrastructure for WSS * * The WSS is configured to have the interface as parent (see wlp_wss_setup()) * a new sysfs directory that includes wssid as its name is created in the * interface's sysfs directory. The group of files interacting with WSS are * created also. */ static int wlp_wss_sysfs_add(struct wlp_wss *wss, char *wssid_str) { struct wlp *wlp = container_of(wss, struct wlp, wss); struct device *dev = &wlp->rc->uwb_dev.dev; int result; result = kobject_set_name(&wss->kobj, "wss-%s", wssid_str); if (result < 0) return result; wss->kobj.ktype = &wss_ktype; result = kobject_init_and_add(&wss->kobj, &wss_ktype, wss->kobj.parent, "wlp"); if (result < 0) { dev_err(dev, "WLP: Cannot register WSS kobject.\n"); goto error_kobject_register; } result = sysfs_create_group(&wss->kobj, &wss_attr_group); if (result < 0) { dev_err(dev, "WLP: Cannot register WSS attributes: %d\n", result); goto error_sysfs_create_group; } return 0; error_sysfs_create_group: kobject_put(&wss->kobj); /* will free name if needed */ return result; error_kobject_register: kfree(wss->kobj.name); wss->kobj.name = NULL; wss->kobj.ktype = NULL; return result; } /** * Release WSS * * No more references exist to this WSS. We should undo everything that was * done in wlp_wss_create_activate() except removing the group. The group * is not removed because an object can be unregistered before the group is * created. We also undo any additional operations on the WSS after this * (addition of members). * * If memory was allocated for the kobject's name then it will * be freed by the kobject system during this time. * * The EDA cache is removed and reinitilized when the WSS is removed. We * thus loose knowledge of members of this WSS at that time and need not do * it here. */ void wlp_wss_release(struct kobject *kobj) { struct wlp_wss *wss = container_of(kobj, struct wlp_wss, kobj); wlp_wss_reset(wss); } /** * Enroll into a WSS using provided neighbor as registrar * * First search the neighborhood information to learn which neighbor is * referred to, next proceed with enrollment. * * &wss->mutex is held */ static int wlp_wss_enroll_target(struct wlp_wss *wss, struct wlp_uuid *wssid, struct uwb_dev_addr *dest) { struct wlp *wlp = container_of(wss, struct wlp, wss); struct device *dev = &wlp->rc->uwb_dev.dev; struct wlp_neighbor_e *neighbor; int result = -ENXIO; struct uwb_dev_addr *dev_addr; mutex_lock(&wlp->nbmutex); list_for_each_entry(neighbor, &wlp->neighbors, node) { dev_addr = &neighbor->uwb_dev->dev_addr; if (!memcmp(dest, dev_addr, sizeof(*dest))) { result = wlp_enroll_neighbor(wlp, neighbor, wss, wssid); break; } } if (result == -ENXIO) dev_err(dev, "WLP: Cannot find neighbor %02x:%02x. \n", dest->data[1], dest->data[0]); mutex_unlock(&wlp->nbmutex); return result; } /** * Enroll into a WSS previously discovered * * User provides WSSID of WSS, search for neighbor that has this WSS * activated and attempt to enroll. * * &wss->mutex is held */ static int wlp_wss_enroll_discovered(struct wlp_wss *wss, struct wlp_uuid *wssid) { struct wlp *wlp = container_of(wss, struct wlp, wss); struct device *dev = &wlp->rc->uwb_dev.dev; struct wlp_neighbor_e *neighbor; struct wlp_wssid_e *wssid_e; char buf[WLP_WSS_UUID_STRSIZE]; int result = -ENXIO; mutex_lock(&wlp->nbmutex); list_for_each_entry(neighbor, &wlp->neighbors, node) { list_for_each_entry(wssid_e, &neighbor->wssid, node) { if (!memcmp(wssid, &wssid_e->wssid, sizeof(*wssid))) { result = wlp_enroll_neighbor(wlp, neighbor, wss, wssid); if (result == 0) /* enrollment success */ goto out; break; } } } out: if (result == -ENXIO) { wlp_wss_uuid_print(buf, sizeof(buf), wssid); dev_err(dev, "WLP: Cannot find WSSID %s in cache. \n", buf); } mutex_unlock(&wlp->nbmutex); return result; } /** * Enroll into WSS with provided WSSID, registrar may be provided * * @wss: out WSS that will be enrolled * @wssid: wssid of neighboring WSS that we want to enroll in * @devaddr: registrar can be specified, will be broadcast (ff:ff) if any * neighbor can be used as registrar. * * &wss->mutex is held */ static int wlp_wss_enroll(struct wlp_wss *wss, struct wlp_uuid *wssid, struct uwb_dev_addr *devaddr) { int result; struct wlp *wlp = container_of(wss, struct wlp, wss); struct device *dev = &wlp->rc->uwb_dev.dev; char buf[WLP_WSS_UUID_STRSIZE]; struct uwb_dev_addr bcast = {.data = {0xff, 0xff} }; wlp_wss_uuid_print(buf, sizeof(buf), wssid); if (wss->state != WLP_WSS_STATE_NONE) { dev_err(dev, "WLP: Already enrolled in WSS %s.\n", buf); result = -EEXIST; goto error; } if (!memcmp(&bcast, devaddr, sizeof(bcast))) result = wlp_wss_enroll_discovered(wss, wssid); else result = wlp_wss_enroll_target(wss, wssid, devaddr); if (result < 0) { dev_err(dev, "WLP: Unable to enroll into WSS %s, result %d \n", buf, result); goto error; } dev_dbg(dev, "Successfully enrolled into WSS %s \n", buf); result = wlp_wss_sysfs_add(wss, buf); if (result < 0) { dev_err(dev, "WLP: Unable to set up sysfs for WSS kobject.\n"); wlp_wss_reset(wss); } error: return result; } /** * Activate given WSS * * Prior to activation a WSS must be enrolled. To activate a WSS a device * includes the WSS hash in the WLP IE in its beacon in each superframe. * WLP 0.99 [7.2.5]. * * The WSS tag is also computed at this time. We only support one activated * WSS so we can use the hash as a tag - there will never be a conflict. * * We currently only support one activated WSS so only one WSS hash is * included in the WLP IE. */ static int wlp_wss_activate(struct wlp_wss *wss) { struct wlp *wlp = container_of(wss, struct wlp, wss); struct device *dev = &wlp->rc->uwb_dev.dev; struct uwb_rc *uwb_rc = wlp->rc; int result; struct { struct wlp_ie wlp_ie; u8 hash; /* only include one hash */ } ie_data; BUG_ON(wss->state != WLP_WSS_STATE_ENROLLED); wss->hash = wlp_wss_comp_wssid_hash(&wss->wssid); wss->tag = wss->hash; memset(&ie_data, 0, sizeof(ie_data)); ie_data.wlp_ie.hdr.element_id = UWB_IE_WLP; ie_data.wlp_ie.hdr.length = sizeof(ie_data) - sizeof(struct uwb_ie_hdr); wlp_ie_set_hash_length(&ie_data.wlp_ie, sizeof(ie_data.hash)); ie_data.hash = wss->hash; result = uwb_rc_ie_add(uwb_rc, &ie_data.wlp_ie.hdr, sizeof(ie_data)); if (result < 0) { dev_err(dev, "WLP: Unable to add WLP IE to beacon. " "result = %d.\n", result); goto error_wlp_ie; } wss->state = WLP_WSS_STATE_ACTIVE; result = 0; error_wlp_ie: return result; } /** * Enroll in and activate WSS identified by provided WSSID * * The neighborhood cache should contain a list of all neighbors and the * WSS they have activated. Based on that cache we search which neighbor we * can perform the association process with. The user also has option to * specify which neighbor it prefers as registrar. * Successful enrollment is followed by activation. * Successful activation will create the sysfs directory containing * specific information regarding this WSS. */ int wlp_wss_enroll_activate(struct wlp_wss *wss, struct wlp_uuid *wssid, struct uwb_dev_addr *devaddr) { struct wlp *wlp = container_of(wss, struct wlp, wss); struct device *dev = &wlp->rc->uwb_dev.dev; int result = 0; char buf[WLP_WSS_UUID_STRSIZE]; mutex_lock(&wss->mutex); result = wlp_wss_enroll(wss, wssid, devaddr); if (result < 0) { wlp_wss_uuid_print(buf, sizeof(buf), &wss->wssid); dev_err(dev, "WLP: Enrollment into WSS %s failed.\n", buf); goto error_enroll; } result = wlp_wss_activate(wss); if (result < 0) { dev_err(dev, "WLP: Unable to activate WSS. Undoing enrollment " "result = %d \n", result); /* Undo enrollment */ wlp_wss_reset(wss); goto error_activate; } error_activate: error_enroll: mutex_unlock(&wss->mutex); return result; } /** * Create, enroll, and activate a new WSS * * @wssid: new wssid provided by user * @name: WSS name requested by used. * @sec_status: security status requested by user * * A user requested the creation of a new WSS. All operations are done * locally. The new WSS will be stored locally, the hash will be included * in the WLP IE, and the sysfs infrastructure for this WSS will be * created. */ int wlp_wss_create_activate(struct wlp_wss *wss, struct wlp_uuid *wssid, char *name, unsigned sec_status, unsigned accept) { struct wlp *wlp = container_of(wss, struct wlp, wss); struct device *dev = &wlp->rc->uwb_dev.dev; int result = 0; char buf[WLP_WSS_UUID_STRSIZE]; result = wlp_wss_uuid_print(buf, sizeof(buf), wssid); if (!mutex_trylock(&wss->mutex)) { dev_err(dev, "WLP: WLP association session in progress.\n"); return -EBUSY; } if (wss->state != WLP_WSS_STATE_NONE) { dev_err(dev, "WLP: WSS already exists. Not creating new.\n"); result = -EEXIST; goto out; } if (wss->kobj.parent == NULL) { dev_err(dev, "WLP: WSS parent not ready. Is network interface " "up?\n"); result = -ENXIO; goto out; } if (sec_status == WLP_WSS_SECURE) { dev_err(dev, "WLP: FIXME Creation of secure WSS not " "supported yet.\n"); result = -EINVAL; goto out; } wss->wssid = *wssid; memcpy(wss->name, name, sizeof(wss->name)); wss->bcast = wlp_wss_sel_bcast_addr(wss); wss->secure_status = sec_status; wss->accept_enroll = accept; /*wss->virtual_addr is initialized in call to wlp_wss_setup*/ /* sysfs infrastructure */ result = wlp_wss_sysfs_add(wss, buf); if (result < 0) { dev_err(dev, "Cannot set up sysfs for WSS kobject.\n"); wlp_wss_reset(wss); goto out; } else result = 0; wss->state = WLP_WSS_STATE_ENROLLED; result = wlp_wss_activate(wss); if (result < 0) { dev_err(dev, "WLP: Unable to activate WSS. Undoing " "enrollment\n"); wlp_wss_reset(wss); goto out; } result = 0; out: mutex_unlock(&wss->mutex); return result; } /** * Determine if neighbor has WSS activated * * @returns: 1 if neighbor has WSS activated, zero otherwise * * This can be done in two ways: * - send a C1 frame, parse C2/F0 response * - examine the WLP IE sent by the neighbor * * The WLP IE is not fully supported in hardware so we use the C1/C2 frame * exchange to determine if a WSS is activated. Using the WLP IE should be * faster and should be used when it becomes possible. */ int wlp_wss_is_active(struct wlp *wlp, struct wlp_wss *wss, struct uwb_dev_addr *dev_addr) { int result = 0; struct device *dev = &wlp->rc->uwb_dev.dev; DECLARE_COMPLETION_ONSTACK(completion); struct wlp_session session; struct sk_buff *skb; struct wlp_frame_assoc *resp; struct wlp_uuid wssid; mutex_lock(&wlp->mutex); /* Send C1 association frame */ result = wlp_send_assoc_frame(wlp, wss, dev_addr, WLP_ASSOC_C1); if (result < 0) { dev_err(dev, "Unable to send C1 frame to neighbor " "%02x:%02x (%d)\n", dev_addr->data[1], dev_addr->data[0], result); result = 0; goto out; } /* Create session, wait for response */ session.exp_message = WLP_ASSOC_C2; session.cb = wlp_session_cb; session.cb_priv = &completion; session.neighbor_addr = *dev_addr; BUG_ON(wlp->session != NULL); wlp->session = &session; /* Wait for C2/F0 frame */ result = wait_for_completion_interruptible_timeout(&completion, WLP_PER_MSG_TIMEOUT * HZ); if (result == 0) { dev_err(dev, "Timeout while sending C1 to neighbor " "%02x:%02x.\n", dev_addr->data[1], dev_addr->data[0]); goto out; } if (result < 0) { dev_err(dev, "Unable to send C1 to neighbor %02x:%02x.\n", dev_addr->data[1], dev_addr->data[0]); result = 0; goto out; } /* Parse message in session->data: it will be either C2 or F0 */ skb = session.data; resp = (void *) skb->data; if (resp->type == WLP_ASSOC_F0) { result = wlp_parse_f0(wlp, skb); if (result < 0) dev_err(dev, "WLP: unable to parse incoming F0 " "frame from neighbor %02x:%02x.\n", dev_addr->data[1], dev_addr->data[0]); result = 0; goto error_resp_parse; } /* WLP version and message type fields have already been parsed */ result = wlp_get_wssid(wlp, (void *)resp + sizeof(*resp), &wssid, skb->len - sizeof(*resp)); if (result < 0) { dev_err(dev, "WLP: unable to obtain WSSID from C2 frame.\n"); result = 0; goto error_resp_parse; } if (!memcmp(&wssid, &wss->wssid, sizeof(wssid))) result = 1; else { dev_err(dev, "WLP: Received a C2 frame without matching " "WSSID.\n"); result = 0; } error_resp_parse: kfree_skb(skb); out: wlp->session = NULL; mutex_unlock(&wlp->mutex); return result; } /** * Activate connection with neighbor by updating EDA cache * * @wss: local WSS to which neighbor wants to connect * @dev_addr: neighbor's address * @wssid: neighbor's WSSID - must be same as our WSS's WSSID * @tag: neighbor's WSS tag used to identify frames transmitted by it * @virt_addr: neighbor's virtual EUI-48 */ static int wlp_wss_activate_connection(struct wlp *wlp, struct wlp_wss *wss, struct uwb_dev_addr *dev_addr, struct wlp_uuid *wssid, u8 *tag, struct uwb_mac_addr *virt_addr) { struct device *dev = &wlp->rc->uwb_dev.dev; int result = 0; if (!memcmp(wssid, &wss->wssid, sizeof(*wssid))) { /* Update EDA cache */ result = wlp_eda_update_node(&wlp->eda, dev_addr, wss, (void *) virt_addr->data, *tag, WLP_WSS_CONNECTED); if (result < 0) dev_err(dev, "WLP: Unable to update EDA cache " "with new connected neighbor information.\n"); } else { dev_err(dev, "WLP: Neighbor does not have matching WSSID.\n"); result = -EINVAL; } return result; } /** * Connect to WSS neighbor * * Use C3/C4 exchange to determine if neighbor has WSS activated and * retrieve the WSS tag and virtual EUI-48 of the neighbor. */ static int wlp_wss_connect_neighbor(struct wlp *wlp, struct wlp_wss *wss, struct uwb_dev_addr *dev_addr) { int result; struct device *dev = &wlp->rc->uwb_dev.dev; struct wlp_uuid wssid; u8 tag; struct uwb_mac_addr virt_addr; DECLARE_COMPLETION_ONSTACK(completion); struct wlp_session session; struct wlp_frame_assoc *resp; struct sk_buff *skb; mutex_lock(&wlp->mutex); /* Send C3 association frame */ result = wlp_send_assoc_frame(wlp, wss, dev_addr, WLP_ASSOC_C3); if (result < 0) { dev_err(dev, "Unable to send C3 frame to neighbor " "%02x:%02x (%d)\n", dev_addr->data[1], dev_addr->data[0], result); goto out; } /* Create session, wait for response */ session.exp_message = WLP_ASSOC_C4; session.cb = wlp_session_cb; session.cb_priv = &completion; session.neighbor_addr = *dev_addr; BUG_ON(wlp->session != NULL); wlp->session = &session; /* Wait for C4/F0 frame */ result = wait_for_completion_interruptible_timeout(&completion, WLP_PER_MSG_TIMEOUT * HZ); if (result == 0) { dev_err(dev, "Timeout while sending C3 to neighbor " "%02x:%02x.\n", dev_addr->data[1], dev_addr->data[0]); result = -ETIMEDOUT; goto out; } if (result < 0) { dev_err(dev, "Unable to send C3 to neighbor %02x:%02x.\n", dev_addr->data[1], dev_addr->data[0]); goto out; } /* Parse message in session->data: it will be either C4 or F0 */ skb = session.data; resp = (void *) skb->data; if (resp->type == WLP_ASSOC_F0) { result = wlp_parse_f0(wlp, skb); if (result < 0) dev_err(dev, "WLP: unable to parse incoming F0 " "frame from neighbor %02x:%02x.\n", dev_addr->data[1], dev_addr->data[0]); result = -EINVAL; goto error_resp_parse; } result = wlp_parse_c3c4_frame(wlp, skb, &wssid, &tag, &virt_addr); if (result < 0) { dev_err(dev, "WLP: Unable to parse C4 frame from neighbor.\n"); goto error_resp_parse; } result = wlp_wss_activate_connection(wlp, wss, dev_addr, &wssid, &tag, &virt_addr); if (result < 0) { dev_err(dev, "WLP: Unable to activate connection to " "neighbor %02x:%02x.\n", dev_addr->data[1], dev_addr->data[0]); goto error_resp_parse; } error_resp_parse: kfree_skb(skb); out: /* Record that we unsuccessfully tried to connect to this neighbor */ if (result < 0) wlp_eda_update_node_state(&wlp->eda, dev_addr, WLP_WSS_CONNECT_FAILED); wlp->session = NULL; mutex_unlock(&wlp->mutex); return result; } /** * Connect to neighbor with common WSS, send pending frame * * This function is scheduled when a frame is destined to a neighbor with * which we do not have a connection. A copy of the EDA cache entry is * provided - not the actual cache entry (because it is protected by a * spinlock). * * First determine if neighbor has the same WSS activated, connect if it * does. The C3/C4 exchange is dual purpose to determine if neighbor has * WSS activated and proceed with the connection. * * The frame that triggered the connection setup is sent after connection * setup. * * network queue is stopped - we need to restart when done * */ static void wlp_wss_connect_send(struct work_struct *ws) { struct wlp_assoc_conn_ctx *conn_ctx = container_of(ws, struct wlp_assoc_conn_ctx, ws); struct wlp *wlp = conn_ctx->wlp; struct sk_buff *skb = conn_ctx->skb; struct wlp_eda_node *eda_entry = &conn_ctx->eda_entry; struct uwb_dev_addr *dev_addr = &eda_entry->dev_addr; struct wlp_wss *wss = &wlp->wss; int result; struct device *dev = &wlp->rc->uwb_dev.dev; mutex_lock(&wss->mutex); if (wss->state < WLP_WSS_STATE_ACTIVE) { if (printk_ratelimit()) dev_err(dev, "WLP: Attempting to connect with " "WSS that is not active or connected.\n"); dev_kfree_skb(skb); goto out; } /* Establish connection - send C3 rcv C4 */ result = wlp_wss_connect_neighbor(wlp, wss, dev_addr); if (result < 0) { if (printk_ratelimit()) dev_err(dev, "WLP: Unable to establish connection " "with neighbor %02x:%02x.\n", dev_addr->data[1], dev_addr->data[0]); dev_kfree_skb(skb); goto out; } /* EDA entry changed, update the local copy being used */ result = wlp_copy_eda_node(&wlp->eda, dev_addr, eda_entry); if (result < 0) { if (printk_ratelimit()) dev_err(dev, "WLP: Cannot find EDA entry for " "neighbor %02x:%02x \n", dev_addr->data[1], dev_addr->data[0]); } result = wlp_wss_prep_hdr(wlp, eda_entry, skb); if (result < 0) { if (printk_ratelimit()) dev_err(dev, "WLP: Unable to prepare frame header for " "transmission (neighbor %02x:%02x). \n", dev_addr->data[1], dev_addr->data[0]); dev_kfree_skb(skb); goto out; } BUG_ON(wlp->xmit_frame == NULL); result = wlp->xmit_frame(wlp, skb, dev_addr); if (result < 0) { if (printk_ratelimit()) dev_err(dev, "WLP: Unable to transmit frame: %d\n", result); if (result == -ENXIO) dev_err(dev, "WLP: Is network interface up? \n"); /* We could try again ... */ dev_kfree_skb(skb);/*we need to free if tx fails */ } out: kfree(conn_ctx); BUG_ON(wlp->start_queue == NULL); wlp->start_queue(wlp); mutex_unlock(&wss->mutex); } /** * Add WLP header to outgoing skb * * @eda_entry: pointer to neighbor's entry in the EDA cache * @_skb: skb containing data destined to the neighbor */ int wlp_wss_prep_hdr(struct wlp *wlp, struct wlp_eda_node *eda_entry, void *_skb) { struct device *dev = &wlp->rc->uwb_dev.dev; int result = 0; unsigned char *eth_addr = eda_entry->eth_addr; struct uwb_dev_addr *dev_addr = &eda_entry->dev_addr; struct sk_buff *skb = _skb; struct wlp_frame_std_abbrv_hdr *std_hdr; if (eda_entry->state == WLP_WSS_CONNECTED) { /* Add WLP header */ BUG_ON(skb_headroom(skb) < sizeof(*std_hdr)); std_hdr = (void *) __skb_push(skb, sizeof(*std_hdr)); std_hdr->hdr.mux_hdr = cpu_to_le16(WLP_PROTOCOL_ID); std_hdr->hdr.type = WLP_FRAME_STANDARD; std_hdr->tag = eda_entry->wss->tag; } else { if (printk_ratelimit()) dev_err(dev, "WLP: Destination neighbor (Ethernet: " "%02x:%02x:%02x:%02x:%02x:%02x, Dev: " "%02x:%02x) is not connected. \n", eth_addr[0], eth_addr[1], eth_addr[2], eth_addr[3], eth_addr[4], eth_addr[5], dev_addr->data[1], dev_addr->data[0]); result = -EINVAL; } return result; } /** * Prepare skb for neighbor: connect if not already and prep WLP header * * This function is called in interrupt context, but it needs to sleep. We * temporarily stop the net queue to establish the WLP connection. * Setup of the WLP connection and restart of queue is scheduled * on the default work queue. * * run with eda->lock held (spinlock) */ int wlp_wss_connect_prep(struct wlp *wlp, struct wlp_eda_node *eda_entry, void *_skb) { int result = 0; struct device *dev = &wlp->rc->uwb_dev.dev; struct sk_buff *skb = _skb; struct wlp_assoc_conn_ctx *conn_ctx; if (eda_entry->state == WLP_WSS_UNCONNECTED) { /* We don't want any more packets while we set up connection */ BUG_ON(wlp->stop_queue == NULL); wlp->stop_queue(wlp); conn_ctx = kmalloc(sizeof(*conn_ctx), GFP_ATOMIC); if (conn_ctx == NULL) { if (printk_ratelimit()) dev_err(dev, "WLP: Unable to allocate memory " "for connection handling.\n"); result = -ENOMEM; goto out; } conn_ctx->wlp = wlp; conn_ctx->skb = skb; conn_ctx->eda_entry = *eda_entry; INIT_WORK(&conn_ctx->ws, wlp_wss_connect_send); schedule_work(&conn_ctx->ws); result = 1; } else if (eda_entry->state == WLP_WSS_CONNECT_FAILED) { /* Previous connection attempts failed, don't retry - see * conditions for connection in WLP 0.99 [7.6.2] */ if (printk_ratelimit()) dev_err(dev, "Could not connect to neighbor " "previously. Not retrying. \n"); result = -ENONET; goto out; } else /* eda_entry->state == WLP_WSS_CONNECTED */ result = wlp_wss_prep_hdr(wlp, eda_entry, skb); out: return result; } /** * Emulate broadcast: copy skb, send copy to neighbor (connect if not already) * * We need to copy skbs in the case where we emulate broadcast through * unicast. We copy instead of clone because we are modifying the data of * the frame after copying ... clones share data so we cannot emulate * broadcast using clones. * * run with eda->lock held (spinlock) */ int wlp_wss_send_copy(struct wlp *wlp, struct wlp_eda_node *eda_entry, void *_skb) { int result = -ENOMEM; struct device *dev = &wlp->rc->uwb_dev.dev; struct sk_buff *skb = _skb; struct sk_buff *copy; struct uwb_dev_addr *dev_addr = &eda_entry->dev_addr; copy = skb_copy(skb, GFP_ATOMIC); if (copy == NULL) { if (printk_ratelimit()) dev_err(dev, "WLP: Unable to copy skb for " "transmission.\n"); goto out; } result = wlp_wss_connect_prep(wlp, eda_entry, copy); if (result < 0) { if (printk_ratelimit()) dev_err(dev, "WLP: Unable to connect/send skb " "to neighbor.\n"); dev_kfree_skb_irq(copy); goto out; } else if (result == 1) /* Frame will be transmitted separately */ goto out; BUG_ON(wlp->xmit_frame == NULL); result = wlp->xmit_frame(wlp, copy, dev_addr); if (result < 0) { if (printk_ratelimit()) dev_err(dev, "WLP: Unable to transmit frame: %d\n", result); if ((result == -ENXIO) && printk_ratelimit()) dev_err(dev, "WLP: Is network interface up? \n"); /* We could try again ... */ dev_kfree_skb_irq(copy);/*we need to free if tx fails */ } out: return result; } /** * Setup WSS * * Should be called by network driver after the interface has been given a * MAC address. */ int wlp_wss_setup(struct net_device *net_dev, struct wlp_wss *wss) { struct wlp *wlp = container_of(wss, struct wlp, wss); struct device *dev = &wlp->rc->uwb_dev.dev; int result = 0; mutex_lock(&wss->mutex); wss->kobj.parent = &net_dev->dev.kobj; if (!is_valid_ether_addr(net_dev->dev_addr)) { dev_err(dev, "WLP: Invalid MAC address. Cannot use for" "virtual.\n"); result = -EINVAL; goto out; } memcpy(wss->virtual_addr.data, net_dev->dev_addr, sizeof(wss->virtual_addr.data)); out: mutex_unlock(&wss->mutex); return result; } EXPORT_SYMBOL_GPL(wlp_wss_setup); /** * Remove WSS * * Called by client that configured WSS through wlp_wss_setup(). This * function is called when client no longer needs WSS, eg. client shuts * down. * * We remove the WLP IE from the beacon before initiating local cleanup. */ void wlp_wss_remove(struct wlp_wss *wss) { struct wlp *wlp = container_of(wss, struct wlp, wss); mutex_lock(&wss->mutex); if (wss->state == WLP_WSS_STATE_ACTIVE) uwb_rc_ie_rm(wlp->rc, UWB_IE_WLP); if (wss->state != WLP_WSS_STATE_NONE) { sysfs_remove_group(&wss->kobj, &wss_attr_group); kobject_put(&wss->kobj); } wss->kobj.parent = NULL; memset(&wss->virtual_addr, 0, sizeof(wss->virtual_addr)); /* Cleanup EDA cache */ wlp_eda_release(&wlp->eda); wlp_eda_init(&wlp->eda); mutex_unlock(&wss->mutex); } EXPORT_SYMBOL_GPL(wlp_wss_remove);